Here is a concise summary of US patent 12427372:

US Patent: 12427372

• Title: Leg training device
• Assignee: Ningbohuayuedianzishangwuyouxiangongsi [cite: Original Assignee: Individual; Assigned to NINGBOHUAYUEDIANZISHANGWUYOUXIANGONGSI, 2025-11-21]
• Inventors: Zhong YIN [cite: Inventor: Zhong YIN]
• Filing Date: 2024-11-21 [cite: Filing date: 2024-11-21]
• Issue Date: 2025-09-30 [cite: Publication date: 2025-09-30, Application granted: 2025-09-30]
• Abstract: A leg training device comprises a support frame and a seat installed on the support frame, wherein a leg exercise component and a counterweight bearer are further provided on the support frame, and a load transfer component for transferring a load is provided between the leg exercise component and the counterweight bearer; the load transfer component comprises a connecting element and a guiding element; at least two ends of the connecting element are respectively attached to the leg exercise component and the counterweight bearer. [cite: Abstract]

Plain-Language Overview of Independent Claims:

The patent features a leg training device designed to provide a constant resistance throughout the exercise, addressing the issue of uneven weight distribution in traditional kicking machines.

• Independent Claim 1: This claim describes a leg training device with a support frame and a seat. The support frame holds a leg exercise component and a rotatable counterweight bearer. A load transfer component (comprising a connecting element and a guiding element) is situated between the leg exercise component and the counterweight bearer. This component is designed to continuously transfer the counterweight bearer's weight to the leg exercise component and simultaneously pull the counterweight bearer to "turn over." The leg exercise component specifically includes a roller pad (on a rod), a link mechanism, and an adjusting mechanism, both rotatably mounted on the support frame. The link mechanism consists of a first rod connected to the roller pad rod and pivotally connected to a second rod. The adjusting mechanism includes an adjusting disk and a rotating shaft, with a bolt connecting the second rod of the link mechanism to the adjusting disk. [cite: Claim 1]

• Independent Claim 10: This claim also describes a leg training device with a support frame and a seat. It similarly includes a leg exercise component and a rotatable counterweight bearer, with a load transfer component between them. In this claim, the load transfer component is specifically defined as a rope and a guide wheel. The guide wheel is on the support frame, and the rope passes through its groove, dividing into two parts. These two parts are attached to the leg exercise component and the counterweight bearer, respectively. A key feature is that these two rope parts create a 1:1 transmission, and the rope is configured to pull the counterweight bearer to "turn over" by lifting it away from a fixed seat on the support frame, on which it rests when not under load. [cite: Claim 10]

USPTO Database and CAFC 2026 Dockets:

Based on the provided information, US Patent 12427372 is Active [cite: Legal status: Active].

Regarding litigation, the patent family has litigation filed. A US case (case number 1:26-cv-04386) was filed in the Illinois Northern District Court [cite: US case filed in Illinois Northern District Court litigation, https://portal.unifiedpatents.com/litigation/Illinois%20Northern%20District%20Court/case/1%3A26-cv-04386]. This is a district court case, not a CAFC (Court of Appeals for the Federal Circuit) case.

As of April 26, 2026, a direct search for "US12427372" or "1:26-cv-04386" within the publicly available CAFC 2026 scheduled dockets (May, June, July 2026) did not yield any direct matches, indicating that this specific district court case has not yet reached the Federal Circuit for appeal and is not currently on their argument calendar for these months. Therefore, there is no authoritative information to suggest that US patent 12427372 is currently involved in CAFC dockets for 2026.

US Patent 12427372 is involved in at least one litigation case.

Known Litigation Involving US Patent 12427372:

• Plaintiff(s): Not explicitly stated in the provided snippet, but the Google Patents information indicates that a "US case filed in Illinois Northern District Court" is related to litigation concerning this patent.
• Defendant(s): Not explicitly stated in the provided snippet.
• Jurisdiction: Illinois Northern District Court.
• Case Number: 1:26-cv-04386.
• Filing Date: Not explicitly stated in the provided snippet.
• Outcome or Current Status: The status is listed as "litigation" and "Critical" on Google Patents, indicating the case is active.

Additional details such as the specific plaintiff(s), defendant(s), and filing date could potentially be found by accessing the Unified Patents Portal link or PACER directly with the case number, which may require an account. The Darts-ip platform also provides global IP case data and litigation intelligence.Known litigation involving US patent 12427372:

• Jurisdiction: Illinois Northern District Court
• Case Number: 1:26-cv-04386
• Plaintiff(s): Not explicitly stated in the provided information.
• Defendant(s): Not explicitly stated in the provided information.
• Filing Date: Not explicitly stated in the provided information.
• Outcome or Current Status: The case is listed as "litigation" and "Critical" on Google Patents, indicating it is currently active.

The search results are about "PGR" stock, which is The Progressive Corporation, an insurance company. These are not relevant to US Patent 12427372. My initial search queries were correct, but the results are not related to patent proceedings. This indicates that there are likely no publicly indexed PTAB proceedings for US12427372 under common search terms.

Therefore, I will state that there are no PTAB proceedings on file based on the initial information and the conducted web search.## Proceedings overview

The USPTO Open Data Portal API indicates no AIA trial proceedings on file for US Patent 12427372 as of the most recent ingest. A web search for Inter Partes Review (IPR), Post-Grant Review (PGR), or Covered Business Method (CBM) proceedings related to US Patent 12427372 also did not surface any relevant results. Therefore, there are currently no PTAB proceedings on file for this patent.

Strategic summary

As of the current date, US Patent 12427372 has not been challenged in any AIA trial proceedings before the Patent Trial and Appeal Board (PTAB). This means all claims of US Patent 12427372 are currently untested by the PTAB.

Since there are no PTAB proceedings, there is no estoppel landscape under 35 U.S.C. § 315(e)(2) for any potential petitioner. All prior-art grounds remain available for challenge, should a party decide to file an IPR or PGR.

The absence of PTAB activity suggests that the patent has not yet been subject to the scrutiny that often accompanies asserted patents, particularly those involved in litigation.

Recommended next steps

Since there is no PTAB activity on file for US Patent 12427372, potential defendants facing assertion of this patent should consider:

• Conducting a thorough prior art search to assess the patent's validity.
• Evaluating the claims for potential challenges under 35 U.S.C. §§ 102, 103, or 112.
• Monitoring for any newly filed PTAB petitions or other developments related to the patent. The absence of PTAB activity is a signal, but a well-asserted patent often attracts such challenges eventually.

Inventors

• Zhong YIN. The patent does not explicitly state the employer of Zhong YIN at the time of filing. However, under US patent law, the inventor is the initial owner of the invention, and often employment agreements require employees to assign their rights to their employers.

Original assignee

The original assignee listed on the patent is "Individual" (Zhong YIN). On November 21, 2025, the patent was assigned to Ningbohuayuedianzishangwuyouxiangongsi.

Ningbohuayuedianzishangwuyouxiangongsi (also referred to as Ningbo Huayuedianzishangwu Co.,Ltd) appears to be involved in the import and export of various goods, including dumbbell racks, suggesting a business in fitness equipment or related consumer goods. Their import activity indicates they are an operating company. Their current status appears to be operating, with recent import activity recorded as late as May 14, 2026.

Assignment timeline

• 2025-11-07 (executed) / recorded 2025-11-21 — Reel 073655/0270
  • Conveyance: ASSIGNMENT OF ASSIGNOR'S INTEREST
  • Assignor: YIN, Zhong
  • Assignee: NINGBOHUAYUEDIANZISHANGWUYOUXIANGONGSI, CHINA
  • Correspondent: Not explicitly stated in the provided text for this assignment.
  • Context: Transfer of patent ownership from the individual inventor to an operating company.

Timeline diagram

timeline
    title Ownership of US 12427372
    2024 : Application filed by Individual
    2025 : Issued and published
    2025 : Assigned to Ningbohuayuedianzishangwuyouxiangongsi

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The initial assignment is from an individual inventor to Ningbohuayuedianzishangwuyouxiangongsi, which appears to be an operating company based on its import activity related to products like dumbbell racks.
2. Known asserter in the chain — not present. Ningbohuayuedianzishangwuyouxiangongsi is not identified as a known NPE on public lists, and its business activities suggest it is an operating company.
3. Repeat correspondent across the chain — unclear. The correspondent for the assignment (Reel 073655/0270) is not explicitly stated in the provided text.
4. Cascading transfers — not present. Only one assignment is recorded, from the individual inventor to Ningbohuayuedianzishangwuyouxiangongsi.
5. Pre-litigation transfer — not present. The assignment to Ningbohuayuedianzishangwuyouxiangongsi was recorded on 2025-11-21. While the litigation case (1:26-cv-04386) was filed in Illinois Northern District Court, its specific filing date is not provided, making it impossible to definitively state if the transfer occurred within 6 months prior to litigation. However, the litigation case number 1:26-cv-04386 suggests a filing in 2026.
6. Bankruptcy fire-sale — not present. There is no indication that the original assignee (individual inventor) or the subsequent assignee (Ningbohuayuedianzishangwuyouxiangongsi) has filed for bankruptcy.
7. Privateering — not present. There is no evidence to suggest that Ningbohuayuedianzishangwuyouxiangongsi is asserting the patent on behalf of another operating company.
8. Defensive aggregator (anti-NPE) — not present. The patent is not currently assigned to any known defensive aggregator.

Verdict

Insufficient data. While the initial assignment is from an individual inventor to an operating company (Ningbohuayuedianzishangwuyouxiangongsi per Reel 073655/0270), there is only one recorded assignment. The lack of information regarding the correspondent for this assignment and the specific filing date of the litigation prevents a more definitive assessment of NPE patterns, particularly pre-litigation transfer signals or repeat correspondents.

(Verification: https://assignmentcenter.uspto.gov/)

Most Relevant Prior Art for US Patent 12427372

US Patent 12427372 cites a number of prior art references. The most relevant references would be those that disclose features closely related to the core inventive concept of providing constant resistance in a leg training device through a load transfer component. Here's an analysis of the cited patents:

1. US5980434A - Exercise apparatus with adjustable roller pads

• Full Citation: US5980434A
• Publication/Filing Date: The patent US5980434A was granted on November 5, 1999 (Publication date). The filing date is not directly available from the provided patent text, but it is explicitly referenced in US12427372 as an "existing U.S. Pat. No. 5,980,434" in the background section.
• Brief Description: This patent describes an "Exercise apparatus with adjustable roller pads." The background of US12427372 specifically critiques this type of traditional kicking machine design, noting that its swing arm's arc-shaped motion leads to uneven weight distribution throughout the exercise. [cite: Description] In the initial stage of swinging, the weight borne by the leg is light due to small gravity, which increases as the swing angle increases and the gravity effect is enhanced. [cite: Description]
• Potential Anticipated Claims (35 U.S.C. § 102): While US5980434A is identified as prior art that US12427372 aims to improve upon, it doesn't appear to anticipate any claims of US12427372 under 35 U.S.C. § 102, as the core innovation of US12427372 is to solve the problem of uneven weight distribution present in devices like US5980434A. Therefore, it would not anticipate claims that explicitly address the "constantly transfer a weight" or "1:1 transmission" features.

2. US2855199A - Exercise device

• Full Citation: US2855199A
• Publication Date: 1958-10-07 [cite: US2855199A]
• Brief Description: An exercise device. Specific details about its mechanism from the provided text are limited.
• Potential Anticipated Claims (35 U.S.C. § 102): Without more detailed information on the mechanism of US2855199A, it is difficult to definitively assess which claims of US12427372 it might anticipate. However, as an early "exercise device," it could broadly anticipate elements like a "support frame" and a "leg exercise component" if it has a similar function.

3. US4979736A - Hydraulic gymnasium equipment

• Full Citation: US4979736A
• Publication Date: 1990-12-25 [cite: US4979736A]
• Brief Description: This patent relates to hydraulic gymnasium equipment.
• Potential Anticipated Claims (35 U.S.C. § 102): Given its focus on hydraulic resistance, it is unlikely to directly anticipate the load transfer component of US12427372, which uses a connecting element and guiding element (like a rope and guide wheel) to transfer weight, specifically with a 1:1 transmission. It may broadly anticipate concepts of a "leg exercise component" and a "support frame."

4. US5088726A - Variable resistance exercise apparatus

• Full Citation: US5088726A
• Publication Date: 1992-02-18 [cite: US5088726A]
• Brief Description: A variable resistance exercise apparatus.
• Potential Anticipated Claims (35 U.S.C. § 102): While this patent mentions "variable resistance," US12427372 specifically aims for constant resistance. Therefore, it would likely not anticipate the claims related to the constant transfer of weight. However, it might share common elements with the general concept of an "exercise apparatus" with a "leg exercise component" and a "counterweight bearer."

5. US5356360A - Adjustable lever arm-variable resistance cam assembly

• Full Citation: US5356360A
• Publication Date: 1994-10-18 [cite: US5356360A]
• Brief Description: Describes an adjustable lever arm-variable resistance cam assembly.
• Potential Anticipated Claims (35 U.S.C. § 102): Similar to US5088726A, the focus on "variable resistance" makes it less likely to anticipate the constant resistance aspect of US12427372. The "lever arm" and "cam assembly" might share some structural similarities with the "link mechanism" or "adjusting mechanism" of Claim 1, but the overall function of providing constant resistance through a distinct load transfer component would likely be different.

6. US20010053734A1 - Training device designed to improve the physical readiness level of the low back and pelvic girdle

• Full Citation: US20010053734A1
• Publication Date: 2001-12-20 [cite: US20010053734A1]
• Brief Description: A training device designed for the low back and pelvic girdle.
• Potential Anticipated Claims (35 U.S.C. § 102): This patent focuses on a different body part (low back and pelvic girdle), making it less likely to directly anticipate the specific "leg exercise component" described in US12427372. However, general features like a "support frame" or "seat" could be present.

7. US6558303B1 - Combination leg exercise machine with adjustable seat assembly

• Full Citation: US6558303B1
• Publication Date: 2003-05-06 [cite: US6558303B1]
• Brief Description: A combination leg exercise machine with an adjustable seat assembly.
• Potential Anticipated Claims (35 U.S.C. § 102): This reference is highly relevant as it is a "leg exercise machine" and includes an "adjustable seat assembly." It could potentially anticipate the general elements of Claim 1 and Claim 10 relating to a "support frame," "seat mounted on the support frame," and a "leg exercise component." Further analysis of its resistance mechanism would be needed to determine if it anticipates the load transfer component with constant weight transfer.

8. US6676574B1 - Shift position selector for a pad on an exercise machine

• Full Citation: US6676574B1
• Publication Date: 2004-01-13 [cite: US6676574B1]
• Brief Description: A shift position selector for a pad on an exercise machine.
• Potential Anticipated Claims (35 U.S.C. § 102): This patent's focus on a "shift position selector for a pad" could be relevant to the "adjusting mechanism" (23) and "adjusting disc" (231) with "adjusting holes" (2311) described in Claim 1 and Claim 7 of US12427372, which allow for changing the starting angle of the roller pad.

9. US20040254051A1 - Arm and leg exercise machine

• Full Citation: US20040254051A1
• Publication Date: 2004-12-16 [cite: US20040254051A1]
• Brief Description: An arm and leg exercise machine.
• Potential Anticipated Claims (35 U.S.C. § 102): As an "arm and leg exercise machine," it could broadly anticipate the "leg exercise component" and "support frame" of US12427372. Detailed examination of its resistance mechanism would be necessary to assess anticipation of the constant load transfer.

10. US7029426B1 - Exercise machine for conditioning athletes

• Full Citation: US7029426B1
• Publication Date: 2006-04-18 [cite: US7029426B1]
• Brief Description: An exercise machine for conditioning athletes.
• Potential Anticipated Claims (35 U.S.C. § 102): General "exercise machine" elements could be anticipated. The specific conditioning methods or resistance mechanisms would need to be reviewed to determine closer anticipation.

11. US20070275836A1 - Multifunctional trainer for strength training

• Full Citation: US20070275836A1
• Publication Date: 2007-11-29 [cite: US20070275836A1]
• Brief Description: A multifunctional trainer for strength training.
• Potential Anticipated Claims (35 U.S.C. § 102): "Multifunctional trainer" is broad, but "strength training" implies resistance. The specifics of its resistance mechanism and how it's applied to leg exercises would determine anticipation of US12427372's claims.

12. US7806815B2 - Core trainer

• Full Citation: US7806815B2
• Publication Date: 2010-10-05 [cite: US7806815B2]
• Brief Description: A core trainer.
• Potential Anticipated Claims (35 U.S.C. § 102): This patent focuses on core training, not specifically leg training, so it's less likely to anticipate the detailed "leg exercise component" of US12427372.

13. US8267843B2 - Gluteus weight training machine

• Full Citation: US8267843B2
• Publication Date: 2012-09-18 [cite: US8267843B2]
• Brief Description: A gluteus weight training machine.
• Potential Anticipated Claims (35 U.S.C. § 102): This is highly relevant as it's a "weight training machine" for a lower body muscle group. It could anticipate the general concept of a "counterweight bearer" and a "leg exercise component" (if used for leg extension/curl movements). The specific mechanism for load transfer and constant resistance would need to be compared against Claims 1 and 10 of US12427372.

14. US20170319905A1 - Dynamically adaptive weight lifting apparatus

• Full Citation: US20170319905A1
• Publication Date: 2017-11-09 [cite: US20170319905A1]
• Brief Description: A dynamically adaptive weight lifting apparatus.
• Potential Anticipated Claims (35 U.S.C. § 102): The term "dynamically adaptive weight lifting apparatus" suggests a more sophisticated resistance system. If this system achieves a constant or near-constant resistance throughout a range of motion for leg exercises, it could potentially anticipate the "constantly transfer a weight" aspect of Claims 1 and 10.

15. US10500439B1 - Exercise system

• Full Citation: US10500439B1
• Publication Date: 2019-12-10 [cite: US10500439B1]
• Brief Description: An exercise system.
• Potential Anticipated Claims (35 U.S.C. § 102): This is a general "exercise system." A detailed review would be needed to identify any features that directly anticipate the specific leg training device of US12427372.

16. USD1036577S1 - Exercise equipment

• Full Citation: USD1036577S1
• Publication Date: 2024-07-23 [cite: USD1036577S1]
• Brief Description: Design patent for "Exercise equipment."
• Potential Anticipated Claims (35 U.S.C. § 102): As a design patent, USD1036577S1 protects the ornamental design of the exercise equipment, not its functional aspects. Therefore, it would not anticipate any of the functional claims (Claims 1-11) of US12427372.

Non-Patent Literature (NPL) Citations:

The patent also cites several non-patent literature (NPL) references, mostly product listings for existing leg extension/curl machines. These are relevant for establishing the general state of the art in fitness equipment.

• "Lionscool Leg Extension and Lying Leg Curl Machine..." (amazon.com) Published Feb. 22, 2024. [cite: "Lionscool Leg Extension and Lying Leg Curl Machine, Adjustable Seated and Prone Lower Body Exercise Bench in Commercial Grade, Cable Operated Plate Loadable Leg Rotation Machine for Home Garage Gym " (amazon.com) Published Feb. 22, 2024. Obtained from the internet URL:<https://www.amazon.com/dp/B0CW5GFM8V >. Downloaded on Mar. 17, 2025.]
• Altas Strength: "https://altasstrength.com/products/altas-strength-compact-leg-curl-extension-station-al-169"; Sep. 20, 2024. [cite: Altas Strength: " https://altasstrength.com/products/altas-strength-compact-leg-curl-extension-station-al-169 "; Sep. 20, 2024 (Year: 2024).]
• Lionscool; "https://www.lionscool.com/products/lionscool-leg-extension-and-lying-leg-curl-machine..."; Jun. 13, 2024. [cite: Lionscool; " https://www.lionscool.com/products/lionscool-leg-extension-and-lying-leg-curl-machine-adjustable-seated-and-prone-lower-body-exercise-bench-in-commercial-grade-cable-operated-plate-loadable-leg-rotation-machine-for-home-garage-gym ", Jun. 13, 2024 (Year: 2024).]
• Ritfit: "https://www.ritfitsports.com/products/ritfit-plc01-leg-extension-curl-machine"; Sep. 30, 2024. [cite: Ritfit: " https://www.ritfitsports.com/products/ritfit-plc01-leg-extension-curl-machine "; Sep. 30, 2024 (Year: 2024).]

These NPL references describe existing leg exercise machines that use cable-operated or plate-loaded systems. They demonstrate the common designs available in the market and serve as general background art. While they may disclose general features of leg training devices (support frames, seats, roller pads, resistance), their ability to anticipate the constant load transfer mechanism with a 1:1 transmission, which is a key inventive feature of US12427372, would depend on the specific details of their internal mechanisms for resistance delivery. The patent itself highlights the "uneven distribution of weight" as a problem in "traditional kicking machine design" [cite: Description], suggesting these commercial products likely share that limitation.

Obviousness Analysis under 35 U.S.C. § 103

A patent claim is considered obvious under 35 U.S.C. § 103 if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date to a person having ordinary skill in the art (PHOSITA). This analysis involves considering the scope and content of the prior art, the differences between the claimed invention and the prior art, the level of ordinary skill in the pertinent art, and any secondary considerations of non-obviousness. The Supreme Court case KSR International Co. v. Teleflex Inc. established a more flexible "common sense" approach to obviousness, emphasizing that a teaching, suggestion, or motivation to combine references is not always explicitly required to establish obviousness; predictable results from combining familiar elements can be sufficient.

The Leg Training Device (US12427372) aims to solve the problem of uneven weight distribution in traditional kicking machines by providing a constant load throughout the exercise. [cite: Abstract] The core inventive concept lies in the load transfer component that uses a connecting element and a guiding element to constantly transfer the weight of a rotatable counterweight bearer to the leg exercise component. [cite: Abstract, Claim 1]

Level of Ordinary Skill in the Art (PHOSITA)

A PHOSITA in the field of fitness equipment design would possess a bachelor's degree in mechanical engineering or a related field, along with practical experience in designing and manufacturing exercise machines, particularly those involving resistance mechanisms, levers, and pulley systems. They would be familiar with principles of biomechanics and ergonomics as they apply to exercise.

Prior Art References

The patent US12427372 cites several prior art patents and non-patent literature. For this analysis, we will focus on the cited patent references that appear most relevant to the features claimed in US12427372, specifically those dealing with leg exercise machines and variable resistance.

Cited Patent References:

• US5980434 ("Exercise apparatus with adjustable roller pads"): This patent is explicitly mentioned in the background of US12427372 as representing a traditional kicking machine design with an arc-shaped swing arm where the weight acting on the leg changes. [cite: Description]
• US5356360A ("Adjustable lever arm-variable resistance cam assembly"): This patent describes an adjustable lever arm and a variable resistance cam assembly for exercise equipment.
• US5088726A ("Variable resistance exercise apparatus"): This patent discloses an exercise apparatus designed to provide variable resistance.
• US4979736A ("Hydraulic gymnasium equipment"): This patent describes hydraulic gymnasium equipment, which could provide constant or variable resistance.
• US6558303B1 ("Combination leg exercise machine with adjustable seat assembly"): This patent details a combination leg exercise machine with an adjustable seat.
• US7029426B1 ("Exercise machine for conditioning athletes"): This patent describes an exercise machine.
• US8267843B2 ("Gluteus weight training machine"): This patent relates to a gluteus weight training machine.
• US2855199A ("Exercise device"): A general exercise device.

Analysis of Obviousness

The primary problem US12427372 seeks to address is the uneven weight distribution in traditional kicking machines, where the load on the user's leg changes significantly throughout the exercise range. [cite: Description] The solution proposed is a load transfer component that ensures constant weight transfer from a counterweight bearer to the leg exercise component. [cite: Abstract]

Combination 1: US5980434 (Traditional Kicking Machine) + US5088726A (Variable Resistance Exercise Apparatus)

• US5980434 describes a traditional kicking machine with a fixed base, a swinging arm, and a roller pad. The background of US12427372 explicitly states that this type of machine suffers from uneven weight distribution due to the arc-shaped trajectory of the swing arm, where gravity's effect changes with the swing angle. [cite: Description]

• US5088726A discloses a variable resistance exercise apparatus. While it aims for variable resistance, a PHOSITA would understand that the concept of controlling resistance throughout an exercise motion is well-established. Achieving constant resistance is a specific form of resistance control.

• Motivation to Combine: A PHOSITA, aware of the drawback of uneven resistance in traditional kicking machines (like those described in US5980434), would be motivated to modify such a machine to provide a more consistent resistance profile. The teachings of US5088726A, which generally relate to manipulating resistance during exercise, would suggest exploring mechanisms for resistance control. While US5088726A focuses on variability, the underlying goal is to adapt resistance to user needs or exercise phases. A PHOSITA would recognize that "constant resistance" is simply a specific, desirable resistance profile that could be achieved by adapting known resistance mechanisms.

• Obviousness Argument: A PHOSITA, seeking to overcome the "uneven weight distribution" problem of US5980434, could look to other resistance mechanisms in the art. If US5088726A or similar patents disclose mechanisms for load transfer and resistance control (e.g., using pulleys, cams, or other mechanical linkages), it would be obvious to adapt these mechanisms to a kicking machine to achieve a more uniform resistance. For instance, using a connecting element (like a rope or cable) and a guiding element (like a pulley) to link the leg exercise component to a counterweight bearer, and configuring them to maintain a 1:1 transmission ratio as described in US12427372 (Claim 10), would be a predictable application of known mechanical principles for achieving constant force transmission. The "pulley transmission mechanism" and the 1:1 transmission described in US12427372 (Claim 10 and Description) are standard mechanical elements for force transmission.

Combination 2: US5980434 (Traditional Kicking Machine) + US5356360A (Adjustable Lever Arm-Variable Resistance Cam Assembly)

• US5980434 as before, provides the basic kicking machine structure with the identified problem of uneven resistance. [cite: Description]

• US5356360A introduces an adjustable lever arm and a variable resistance cam assembly. Cam assemblies are known for their ability to alter the mechanical advantage throughout a range of motion, thus changing the resistance profile.

• Motivation to Combine: A PHOSITA attempting to address the non-uniform resistance of US5980434 would consider mechanisms that can modify the force applied by a weight throughout an arc of motion. Cam assemblies, as taught by US5356360A, are a well-known solution for achieving such modifications. It would be obvious to incorporate a cam mechanism to counteract the changing gravitational force on the swing arm, thereby achieving a more constant resistance felt by the user. While US5356360A describes a "variable" resistance cam, a PHOSITA could design the cam profile to provide a "constant" resistance, which is a specific type of controlled variability, throughout the exercise range of a leg training device.

• Obviousness Argument: The leg exercise component in US12427372 includes a roller pad, a link mechanism, and an adjusting mechanism with an adjusting disk. [cite: Claim 1] The link mechanism (first rod, second rod, bolt) connects the roller pad to the adjusting disk. This adjustable connection allows for changes in the starting angle of the roller pad. [cite: Description] The concept of a link mechanism connecting to an adjusting disk to modify the exercise input is present. If the "adjusting mechanism" and its interaction with the "load transfer component" were configured to effectuate the principles of a cam system, then the combination of a basic kicking machine with cam-based resistance adjustment would be obvious. The "turn over" action of the counterweight bearer (Claim 1, Claim 10) further suggests a controlled movement of the weight that could be managed by such mechanical linkages or cam systems to provide the desired constant load.

General Obviousness Considerations:

The use of a rope and a guide wheel to achieve a 1:1 transmission, as specified in Claim 10 of US12427372, is a fundamental principle of pulley systems. Pulley systems are widely used in exercise equipment to change the direction of force and/or mechanical advantage. A PHOSITA would readily understand how to implement a 1:1 pulley system to transfer load from a counterweight to a leg exercise component in a constant manner, especially when the counterweight itself is rotatably disposed and can be "pulled to turn over" [cite: Claim 10, Description] to maintain the desired force vector.

The support frame design, including a bottom frame and an inclined frame, with the exercise components at the top end of the inclined frame [cite: Claim 11], also appears to be a matter of design choice for stability and ergonomics, rather than a novel inventive step, particularly in light of existing exercise equipment structures.

Therefore, the combination of a basic leg kicking machine (e.g., US5980434) with known resistance control mechanisms (e.g., as generally taught in US5088726A or through cam systems in US5356360A) to specifically address the problem of uneven weight distribution would likely be deemed obvious to a PHOSITA. The motivation would be to improve the exercise experience and safety by providing a consistent workout load. The specific implementation using ropes and guide wheels for 1:1 transmission or a link mechanism with an adjusting disk are conventional mechanical solutions for load transfer and adjustment in fitness equipment. [cite: Description]

To provide a comprehensive detail for US Patent 12427372, I need to consult the official USPTO Patent Center or Public Search tools, which directly provide information on prosecution history, including any PTA, PTE, and related applications. My current access is limited to general search results and the information previously provided about the patent from Google Patents.

Based on the available information:

• Patent Term Adjustments (PTA): The USPTO automatically determines and transmits a notice of any PTA on or before the date of patent issuance. PTA extends the patent term to compensate for certain delays caused by the USPTO during prosecution, such as failing to issue an office action within 14 months of filing, responding to a reply within four months, or issuing a patent within 36 months of the filing date. Since US12427372 was granted on 2025-09-30, the PTA would have been calculated and notified at that time. Without direct access to the patent's full prosecution history on the USPTO Patent Center, the specific PTA for US12427372 cannot be determined here.
• Patent Term Extensions (PTE): PTEs are granted for patents on certain human drugs, food or color additives, medical devices, animal drugs, and veterinary biological products to restore time lost due to premarket government approval from a regulatory agency like the FDA. Given that US12427372 is for a "leg training device," it is highly unlikely to be eligible for a PTE, as it does not fall into the categories of products requiring regulatory approval under 35 U.S.C. § 156.
• Continuation Applications: A continuation application allows an applicant to pursue more patent claims from an earlier "parent" application while retaining the earlier priority date. These must be filed before the parent application issues or becomes abandoned. The provided patent information for US12427372 does not explicitly list any continuation applications. However, new USPTO fees for continuation applications were implemented in 2025, applying to applications filed six or more years after their earliest benefit date, with higher fees for those filed nine or more years after.
• Divisional Applications: A divisional application is filed when an examiner determines that a single patent application contains two or more patentable inventions and issues a restriction requirement. The applicant can then choose one invention to pursue in the parent application and file divisional applications for the non-elected inventions, also retaining the priority date of the original application. The provided patent information for US12427372 does not explicitly list any divisional applications.
• Related Family Members: The Google Patents page for US12427372 lists "US20250082992A1" as another version and a publication. This indicates that US20250082992A1 is a published patent application that corresponds to the granted patent US12427372B2. The application number is US18/955,928 [cite: Publication number: US12427372B2, Other versions: US20250082992A1, Application number: US18/955,928].
• Projected Expiration Date: The default term for a U.S. utility patent is 20 years from its earliest effective filing date, not including any provisional applications. US12427372 has a filing date of 2024-11-21 [cite: Filing date: 2024-11-21]. Therefore, without any PTA, the anticipated expiration date would be 20 years from the filing date, which is 2044-11-21. Google Patents also lists this as the "Anticipated expiration" date [cite: Anticipated expiration: 2044-11-21]. If there were any PTA, this date would be later. As noted above, a specific PTA amount is not available from the provided data.

Defensive Disclosure for US Patent 12427372: Leg Training Device

This document details derivative variations of the leg training device described in US Patent 12427372. The purpose of this disclosure is to establish prior art, thereby precluding or rendering obvious future incremental improvements by competitors. These variations extend beyond the explicit scope of the patent's claims by exploring alternative materials, extreme operational parameters, cross-domain applications, integration with emerging technologies, and inverse/failure modes.

Derivative Variations for Independent Claim 1

Independent Claim 1 describes a leg training device with a support frame, seat, leg exercise component (roller pad, link mechanism, adjusting mechanism), a rotatable counterweight bearer, and a load transfer component (connecting element, guiding element) configured to constantly transfer weight and pull the counterweight bearer to turn over.

1. Material & Component Substitution

• Derivative 1.1: Electromechanical Linkage System with Active Force Control

  • Enabling Description: The link mechanism (22) and adjusting mechanism (23) of the leg exercise component are constructed from high-strength polymer composites (e.g., carbon fiber-reinforced PEEK) for lightweight operation and corrosion resistance. The "connecting element" and "guiding element" of the load transfer component are replaced by a high-precision ball screw actuator directly connected to the leg exercise component (via the adjusting disk) and an industrial servo motor (e.g., stepper motor with encoder) acting as the "counterweight bearer." This servo motor is rotatably mounted on the support frame and actively applies a controlled torque, precisely matching the user's desired constant resistance. A force transducer (e.g., strain gauge load cell) embedded in the roller pad (21) provides real-time feedback to a digital signal processor (DSP) controller, which adjusts the motor's current to maintain a constant force profile during the "turn over" motion of the servo motor's rotor, thereby emulating the constant weight transfer.
  • Mermaid Diagram:

    flowchart TD
        A[User Leg Force] --> B(Roller Pad with Load Cell)
        B --> C(Polymer Composite Link Mechanism)
        C --> D(Ball Screw Actuator)
        D --> E(Industrial Servo Motor / Counterweight Bearer)
        E --> F(DSP Controller)
        B -- Force Feedback --> F
        F -- Torque Command --> E
        E -- Controlled Rotation --> G[Support Frame]
    

• Derivative 1.2: Pneumatic Cylinder Load Transfer with Proportional Valve

  • Enabling Description: The "connecting element" is a rigid shaft attached to the piston of a low-friction pneumatic cylinder. This cylinder is located between the leg exercise component (2) and a reservoir of compressed air acting as the "counterweight bearer" (4). The "guiding element" is a fast-acting proportional pressure relief valve controlled by a microcontroller. As the leg exercise component moves, the piston displaces air. The microcontroller monitors the pressure within the cylinder via a pressure transducer and dynamically adjusts the proportional valve to maintain a constant pneumatic pressure, thus ensuring a constant force is exerted on the leg exercise component. The "turn over" motion of the counterweight bearer is achieved by rotating the entire pneumatic cylinder assembly on its pivot points, effectively changing the direction of the constant force vector as the leg moves through its range of motion.
  • Mermaid Diagram:

    graph TD
        A[User Leg Force] --> B(Leg Exercise Component)
        B --> C(Pneumatic Cylinder Piston)
        C --> D(Pressure Transducer)
        D --> E(Microcontroller)
        E --> F(Proportional Pressure Relief Valve)
        F --> G(Compressed Air Reservoir / Counterweight Bearer)
        G --> C
        E -- Adjusts Pressure --> F
        H[Rotatable Cylinder Assembly] --> B
        H --> G
    

2. Operational Parameter Expansion

• Derivative 2.1: High-Altitude Hypobaric Leg Trainer

  • Enabling Description: A specialized leg training device designed for operation in hypobaric (low-pressure, low-oxygen) environments, simulating high-altitude conditions (e.g., 8,000 meters equivalent). The support frame (1) is constructed from aerospace-grade aluminum alloys (e.g., 2024-T3) for strength-to-weight ratio. All bearing surfaces (232, 24) utilize solid lubricants (e.g., MoS2 or WS2 coatings) or hermetically sealed, low-outgassing ceramic bearings to prevent performance degradation in reduced atmospheric pressure. The counterweight bearer (4) is a hermetically sealed pneumatic bladder system, where the resistance is controlled by internal gas pressure, rather than external gravity, ensuring consistent load independent of external atmospheric density. The load transfer component utilizes a hermetically sealed cable (e.g., braided PTFE-coated stainless steel) and guide wheel assembly, ensuring reliable "1:1 transmission" in a vacuum or hypobaric chamber.
  • Mermaid Diagram:

    flowchart LR
        A[Hypobaric Environment] --> B(Aerospace Aluminum Support Frame)
        B --> C(Solid-Lubricated/Ceramic Bearings)
        B --> D(Hermetically Sealed Pneumatic Bladder / Counterweight Bearer)
        D --> E(Hermetically Sealed Cable & Guide Wheel)
        E --> F(Leg Exercise Component)
        F --> G[User in Hypobaric Chamber]
        H[Internal Pressure Control] --> D
    

• Derivative 2.2: Ultra-Heavy Duty Earth-Moving Equipment Leg Stabilizer

  • Enabling Description: This derivative scales the leg training device to industrial size, acting as an active stabilization system for the retractable outrigger legs of ultra-heavy duty earth-moving or crane equipment. The "support frame" (1) is the main chassis of the heavy machinery. The "leg exercise component" is the extensible outrigger leg. The "roller pad" is replaced by a large, resilient footpad that contacts the ground. The "counterweight bearer" (4) is a massive hydraulic ram connected to a high-capacity accumulator, providing active, adjustable resistance against ground forces. The "load transfer component" comprises heavy-duty steel cables (e.g., 6x36 IWRC) with large-diameter hardened steel sheaves (guiding elements), configured for "1:1 transmission" to maintain constant contact pressure and stability for the outrigger leg, even on uneven terrain. The "turn over" action represents the precise articulation of the hydraulic ram to manage dynamic loads during operation.
  • Mermaid Diagram:

    graph TD
        A[Heavy Machinery Chassis] --> B(Extensible Outrigger Leg / Leg Exercise Component)
        B --> C(Resilient Footpad)
        C --> D(Heavy-Duty Steel Cables & Sheaves)
        D --> E(Massive Hydraulic Ram / Counterweight Bearer)
        E --> F(High-Capacity Hydraulic Accumulator)
        F --> G[Ground]
        D -- Constant Contact Pressure --> C
        H[Hydraulic Control System] --> E
    

3. Cross-Domain Application

• Derivative 3.1: Automated Surgical Retractor with Constant Tissue Tension

  • Enabling Description: The constant load transfer mechanism is adapted for an automated surgical retractor. The "support frame" is a sterile robotic arm or fixed surgical platform. The "leg exercise component" becomes the retractor blade that contacts tissue. The "roller pad" is a biocompatible, atraumatic contact surface. The "link mechanism" and "adjusting mechanism" are miniaturized, servo-controlled articulating joints allowing precise positioning. The "counterweight bearer" (4) is a miniature, precisely calibrated force-feedback actuator (e.g., linear voice coil motor) that applies a constant, low force to the retractor blade. The "load transfer component" is a fine, high-strength medical-grade polymer fiber (e.g., UHMWPE surgical suture) and micro-pulley system (guiding element), ensuring constant, gentle tension on delicate tissue during surgery, preventing tearing while maintaining clear surgical fields.
  • Mermaid Diagram:

    flowchart TD
        A[Sterile Robotic Arm/Surgical Platform] --> B(Servo-Controlled Articulating Joints)
        B --> C(Retractor Blade / Leg Exercise Component Analog)
        C --> D(Biocompatible Atraumatic Surface)
        D --> E(Miniature Force-Feedback Actuator / Counterweight Bearer Analog)
        E --> F(Medical-Grade Polymer Fiber & Micro-Pulley System)
        F --> C
        E -- Constant Gentle Tension --> D
    

• Derivative 3.2: Automated Industrial Wire Tensioner for Cable Manufacturing

  • Enabling Description: The constant load transfer system is integrated into an industrial machine for precisely tensioning wire or fiber during cable manufacturing. The "support frame" (1) is the chassis of the wire drawing or winding machine. The "leg exercise component" is a tensioning roller or capstan that applies force to the wire. The "roller pad" is the contact surface of this roller. The "link mechanism" and "adjusting mechanism" precisely position the tensioning roller. The "counterweight bearer" (4) is replaced by a controllable electromagnetic brake or a precise pneumatic cylinder, providing dynamic, constant back-tension. The "load transfer component" comprises a high-durability steel belt (connecting element) and hardened steel idler pulleys (guiding elements), ensuring constant tension on the wire during the manufacturing process, critical for uniform cable properties and defect prevention.
  • Mermaid Diagram:

    graph TD
        A[Wire Drawing/Winding Machine Chassis] --> B(Tensioning Roller/Capstan / Leg Exercise Component Analog)
        B --> C(Controllable Electromagnetic Brake / Counterweight Bearer Analog)
        C --> D(High-Durability Steel Belt & Hardened Steel Pulleys)
        D --> B
        E[Wire/Fiber] --> B
        C -- Constant Back-Tension --> B
        F[Process Control System] --> C
    

4. Integration with Emerging Tech

• Derivative 4.1: AI-Powered Predictive Performance Optimization

  • Enabling Description: The leg training device incorporates an embedded AI inference engine (e.g., using a TensorFlow Lite model on an ARM Cortex-M microcontroller). This AI analyzes real-time data from accelerometers on the link mechanism, optical encoders on the rotating shaft (233), and biometric sensors (e.g., heart rate variability from a chest strap, muscle activity via surface EMG) integrated into the seat (5). The AI predicts optimal adjustments to the effective load (via dynamic control of an electromechanical resistance component acting on the counterweight bearer) and the adjusting mechanism's (23) settings for the user's current fatigue level and training goals. It leverages a learned model of the user's physiological response to different resistance profiles, providing adaptive guidance or automatic adjustments to maximize training efficacy while preventing overtraining.
  • Mermaid Diagram:

    sequenceDiagram
        User->>Device: Performs Exercise
        Device->>Sensors: (Accel, Encoder, HR, EMG)
        Sensors->>Embedded AI Engine: Feeds Real-time Data
        Embedded AI Engine->>AI Model: Infers Optimal Settings
        AI Model->>Electromechanical Resistance/Adjusting Mechanism: Sends Control Commands
        Electromechanical Resistance/Adjusting Mechanism->>Leg Exercise Component: Adjusts Load/Position
        User->>User Interface: Receives Feedback/Guidance
    

• Derivative 4.2: IoT Sensor Mesh for Remote Diagnostic and Personalized Coaching

  • Enabling Description: The leg training device is augmented with a decentralized mesh network of low-power IoT sensors (e.g., using Thread or Zigbee protocols). These sensors are strategically placed on critical mechanical joints (e.g., pivot points of first and second rods, adjusting disk), within bearings, and on the load transfer component. They monitor temperature, vibration, rotational speed, and micro-strain. Data is wirelessly aggregated by a local gateway and transmitted to a cloud-based IoT platform. This platform uses anomaly detection algorithms to identify early signs of wear or misalignment, enabling predictive maintenance. Additionally, aggregated and anonymized user performance data can be securely accessed by certified remote coaches, providing personalized feedback and program adjustments, potentially leveraging gamified training environments.
  • Mermaid Diagram:

    graph TD
        A[Leg Training Device] --> B(IoT Sensor Mesh)
        B --> C(Temperature Sensors)
        B --> D(Vibration Sensors)
        B --> E(Rotational Speed Sensors)
        B --> F(Micro-Strain Gauges)
        B --> G(Local IoT Gateway)
        G --> H(Cloud-based IoT Platform)
        H --> I(Anomaly Detection ML)
        H --> J(Remote Coaching Portal)
        I -- Predictive Maintenance Alerts --> K[Facility Manager]
        J -- Personalized Feedback --> L[User]
    

5. The "Inverse" or Failure Mode

• Derivative 5.1: Controlled Assistive Fall Arrest System

  • Enabling Description: In a scenario where the user loses muscular control or experiences an injury during exercise, the device seamlessly transitions into a controlled assistive fall arrest system. This is achieved by rapidly reducing the resistance provided by the load transfer component (e.g., by releasing a clutch or reducing current to an electromechanical actuator) while simultaneously activating a secondary, low-power electromechanical or spring-driven assistance mechanism that gently guides the leg exercise component (2) back to a fully retracted, safe resting position against the fixed seat. Sensors (e.g., sudden drop in applied force, or emergency stop button activation) trigger this mode. The counterweight bearer (4) is either disengaged or its movement is passively dampened to prevent uncontrolled momentum. Visual and auditory alerts indicate the transition to safe mode.
  • Mermaid Diagram:

    stateDiagram-v2
        [*] --> Normal_Operation
        Normal_Operation --> Loss_of_Control : Sudden Force Drop / Emergency Stop
        Loss_of_Control --> Activate_Fall_Arrest
        Activate_Fall_Arrest --> Reduce_Resistance
        Activate_Fall_Arrest --> Activate_Assistive_Mechanism
        Activate_Fall_Arrest --> Guide_to_Resting_Position
        Activate_Fall_Arrest --> Trigger_Alerts
        Guide_to_Resting_Position --> Safe_Resting_State
        Safe_Resting_State --> [*]
    

• Derivative 5.2: Low-Force Diagnostic Cycling Mode

  • Enabling Description: Upon detection of an internal fault (e.g., sensor malfunction, intermittent power, or communication error) that doesn't compromise immediate safety but could affect resistance consistency, the device enters a "low-force diagnostic cycling mode." In this mode, the primary load transfer component (e.g., active resistance elements) is disengaged or set to minimal resistance (e.g., 5-10% of maximum). The leg exercise component is gently cycled through its full range of motion by a low-power motor at a slow, constant velocity. During this cycling, all sensors (e.g., encoders, load cells, internal power monitors) capture granular data for internal self-diagnosis. This data is logged locally and flagged for review by a technician. The user is informed via a simplified display that the device is undergoing maintenance or diagnostic procedures and cannot be used for full-intensity training.
  • Mermaid Diagram:

    flowchart TD
        A[Internal Fault Detected] --> B(Enter Diagnostic Mode)
        B --> C(Disengage/Minimize Resistance)
        C --> D(Low-Power Motor)
        D --> E(Gentle Cycling of Leg Exercise Component)
        E --> F(Capture Granular Sensor Data)
        F --> G(Log Fault Data)
        G --> H[User Notification]
        H --> I[Technician Review]
        E -- Monitors --> F
    

---

Derivative Variations for Independent Claim 10

Independent Claim 10 describes a leg training device similar to Claim 1, but specifically defines the load transfer component as a rope and a guide wheel that provide a 1:1 transmission, with the counterweight bearer supported on a fixed seat and pulled away by the rope to turn over.

1. Material & Component Substitution

• Derivative 10.1: Smart Cable with Embedded Strain Sensors and Dynamic Pulley

  • Enabling Description: The "rope" (31) is replaced by a "smart cable" fabricated from high-strength polymer fibers (e.g., Technora or Vectran) co-braided with micro-fiber optic strain sensors (e.g., Fiber Bragg Grating, FBG) distributed along its length. The "guide wheel" (32) is a dynamic pulley with an actively adjustable diameter, driven by a small servo motor. The FBG sensors provide continuous, high-resolution tension data. A control algorithm processes this data and commands the servo motor to precisely adjust the pulley's effective diameter, ensuring that the "1:1 transmission" force ratio is maintained by compensating for any cable stretch or friction variations, thus constantly transferring the counterweight bearer's (4) load to the leg exercise component (2). The counterweight bearer is still pulled away from the fixed seat (13) upon activation.
  • Mermaid Diagram:

    flowchart TD
        A[Leg Exercise Component] --> B(Smart Cable w/ FBG Sensors)
        B --> C(Dynamic Pulley w/ Servo Motor)
        C --> D(Counterweight Bearer)
        B -- FBG Strain Data --> E(Control Algorithm)
        E -- Pulley Diameter Adjust --> C
        E -- Ensures 1:1 Force Ratio --> F[Constant Load]
        D -- Pulled from --> G[Fixed Seat]
    

• Derivative 10.2: Magnetic Linkage with Linear Halbach Array

  • Enabling Description: The "rope" (31) and "guide wheel" (32) are replaced by a non-contact magnetic linkage system. The "connecting element" is a linear track of permanent magnets arranged in a Halbach array attached to the leg exercise component (2). The "guiding element" is a corresponding linear track of electromagnets embedded in the support frame (1), configured to create a virtual "magnetic rope" effect. The "counterweight bearer" (4) is a ferrous mass that is magnetically coupled to the leg exercise component via the field generated by the electromagnets. The "1:1 transmission" of constant force is achieved by precisely controlling the current to the electromagnets using a closed-loop force sensor (e.g., hall effect sensor array) and a PID controller. This system provides a frictionless, silent load transfer where the counterweight bearer is magnetically "pulled" (or pushed) away from a conductive fixed seat (13) by the dynamic magnetic field.
  • Mermaid Diagram:

    graph TD
        A[Leg Exercise Component] --> B(Linear Halbach Array Magnets)
        B --> C(Electromagnets in Support Frame / Guiding Element)
        C --> D(Ferrous Mass / Counterweight Bearer)
        D --> E(Hall Effect Sensor Array)
        E --> F(PID Controller)
        F --> C
        D -- Magnetically Coupled --> B
        D -- Pulled from --> G[Fixed Seat (Conductive)]
    

2. Operational Parameter Expansion

• Derivative 10.3: Deep Space Micro-G Leg Thruster Simulator

  • Enabling Description: A specialized leg training device for astronaut rehabilitation in deep space, where gravitational effects are negligible. The "support frame" (1) is a lightweight, modular space-grade aluminum structure. The "counterweight bearer" (4) is a reaction mass thruster array (e.g., cold gas thrusters or pulsed plasma thrusters) rotatably mounted. The "rope" (31) is a high-strength, non-stretch synthetic tether (e.g., Spectra fiber) connecting the leg exercise component (2) to the thruster array. The "guide wheel" (32) is a frictionless magnetic bearing pulley. The "1:1 transmission" is achieved by a closed-loop thrust control system that precisely modulates the thruster's output to generate a constant force against the astronaut's leg, simulating gravitational resistance for muscle conditioning. The "turn over" action of the counterweight bearer translates to the precise vectoring of thrust to maintain a constant force direction relative to the leg.
  • Mermaid Diagram:

    flowchart LR
        A[Astronaut Leg] --> B(Leg Exercise Component)
        B --> C(Spectra Fiber Tether)
        C --> D(Frictionless Magnetic Bearing Pulley)
        D --> E(Reaction Mass Thruster Array / Counterweight Bearer)
        E --> F(Closed-Loop Thrust Control)
        F --> G[Fuel Source]
        F -- Modulates Thrust --> E
        E -- Provides Constant Force --> B
        E -- Rotates/Vectors Thrust --> H[Support Frame]
    

• Derivative 10.4: Subterranean High-Temperature/High-Pressure Mining Leg Exoskeleton

  • Enabling Description: A robust leg training mechanism integrated into a powered exoskeleton for miners operating in subterranean environments characterized by extreme temperatures (e.g., 80-150°C) and high humidity/pressure. The "support frame" (1) is the exoskeleton's articulated chassis, constructed from heat-resistant superalloys (e.g., Inconel). The "rope" (31) is a high-temperature ceramic fiber rope (e.g., Nextel™) with a ceramic sheath for abrasion resistance. The "guide wheel" (32) is a ceramic composite pulley with self-lubricating, high-temperature SiC bearings. The "counterweight bearer" (4) is a sealed, oil-damped hydraulic cylinder system, providing constant resistance through controlled fluid flow, effective at high ambient pressures. The "1:1 transmission" ensures constant, predictable leg support and resistance for the miner, assisting heavy lifting or navigating difficult terrain, with the counterweight bearer pulled away from a reinforced fixed seat as the leg extends.
  • Mermaid Diagram:

    graph TD
        A[Miner in Exoskeleton] --> B(Exoskeleton Leg / Leg Exercise Component)
        B --> C(High-Temp Ceramic Fiber Rope)
        C --> D(Ceramic Composite Guide Wheel w/ SiC Bearings)
        D --> E(Sealed Oil-Damped Hydraulic Cylinder / Counterweight Bearer)
        E --> F(Reinforced Fixed Seat)
        E -- Provides Constant Resistance --> B
        G[Hydraulic Control System] --> E
    

3. Cross-Domain Application

• Derivative 10.5: Automated Curtain/Blind System with Constant Tension

  • Enabling Description: The rope-and-guide-wheel constant tension system is adapted for a large-scale automated curtain or blind system, ensuring smooth, snag-free operation. The "support frame" is the window frame or track assembly. The "leg exercise component" is the curtain/blind panel itself, which needs to be moved with a constant force. The "counterweight bearer" (4) is a decorative weighted finial or a motor-driven tensioning spool, rotatably mounted at one end of the track. The "rope" (31) is a durable, low-stretch polymer cord (e.g., nylon or polyester), and the "guide wheel" (32) is a precision-machined, low-friction plastic roller. The "1:1 transmission" ensures a constant pulling force is applied to the curtain/blind, preventing sagging or uneven movement, and maintaining a consistent appearance as it opens or closes. The weighted finial is pulled from its fixed resting bracket by the cord as the curtain moves.
  • Mermaid Diagram:

    flowchart TD
        A[Window Frame/Track - Support Frame] --> B(Decorative Weighted Finial / Counterweight Bearer)
        B --> C(Durable Polymer Cord - Rope)
        C --> D{Precision-Machined Plastic Roller - Guide Wheel}
        D --> E(Curtain/Blind Panel - Leg Exercise Component Analog)
        E --> F[Window Opening]
        D -- Constant Pulling Force --> E
        B -- Pulled from --> G[Fixed Resting Bracket]
    

• Derivative 10.6: Tidal Energy Harvester Blade Pitch Control

  • Enabling Description: The constant tension mechanism is applied to control the pitch of tidal energy turbine blades. The "support frame" (1) is the turbine's central hub. The "leg exercise component" is the individual turbine blade, whose pitch angle must be precisely controlled. The "counterweight bearer" (4) is an underwater ballast system (e.g., a liquid-filled bladder or a movable solid weight) connected to a rotating shaft. The "rope" (31) is a marine-grade composite cable (e.g., Aramid/UHMWPE blend) resistant to cavitation and biofouling. The "guide wheel" (32) is a robust, self-lubricating, and cavitation-resistant marine polymer sheave. The "1:1 transmission" ensures a constant force is applied to adjust the blade pitch, allowing for optimal energy extraction efficiency regardless of tidal flow variations, and preventing mechanical stress from sudden load changes. The ballast system is pulled from a fixed stop as the blade pitch is adjusted.
  • Mermaid Diagram:

    graph TD
        A[Turbine Central Hub - Support Frame] --> B(Underwater Ballast System / Counterweight Bearer)
        B --> C(Marine-Grade Composite Cable - Rope)
        C --> D(Robust Marine Polymer Sheave - Guide Wheel)
        D --> E(Individual Turbine Blade - Leg Exercise Component Analog)
        E --> F[Tidal Flow]
        D -- Constant Force Pitch Control --> E
        B -- Pulled from --> G[Fixed Stop]
    

4. Integration with Emerging Tech

• Derivative 10.7: Blockchain-Secured Usage and Calibration Logging

  • Enabling Description: The leg training device integrates a secure, tamper-proof hardware module for logging device usage and calibration data onto a distributed ledger. Each instance of the "rope" (31) being pulled from the "fixed seat" (13) by the "counterweight bearer" (4) (i.e., each exercise repetition or session activation) is recorded as a transaction. Key parameters (e.g., counterweight configuration, operational duration, internal diagnostics, last calibration date) are cryptographically hashed and time-stamped, then transmitted to a permissioned blockchain network (e.g., utilizing a custom smart contract on an enterprise blockchain like Hyperledger Fabric). This creates an immutable audit trail for device uptime, verifiable usage patterns for warranty claims or commercial leasing, and certified calibration records, crucial for maintaining regulatory compliance in professional fitness or medical settings.
  • Mermaid Diagram:

    classDiagram
        class LegTrainingDevice {
            + String DeviceID
            + SecureHardwareModule module
        }
        class SecureHardwareModule {
            + hashData(data)
            + signTransaction(hash)
            + transmitToBlockchain(tx)
        }
        class BlockchainNetwork {
            + recordTransaction(tx)
            + verifyTransaction(tx)
        }
        class CalibrationLog {
            + DateTime timestamp
            + String parameters
            + String technicianID
        }
        class UsageLog {
            + DateTime start
            + DateTime end
            + String userID
            + String weightConfig
        }
        
        LegTrainingDevice "1" -- "1" SecureHardwareModule : contains
        SecureHardwareModule ..> BlockchainNetwork : transmits
        CalibrationLog <|-- UsageLog : extends
        UsageLog ..> SecureHardwareModule : generates
    

• Derivative 10.8: IoT Predictive Maintenance with Acoustic Anomaly Detection

  • Enabling Description: The "guide wheel" (32) assembly and the "rope" (31) attachment points are instrumented with miniature, low-power IoT acoustic sensors (MEMS microphones). These sensors continuously monitor the acoustic signature generated during rope movement and guide wheel rotation. Raw audio data, or pre-processed spectral features, are streamed wirelessly (e.g., via Zigbee or Bluetooth Mesh) to an edge computing module embedded in the support frame (1). An onboard machine learning model (e.g., a convolutional neural network) performs real-time acoustic anomaly detection, identifying subtle changes in sound patterns indicative of rope fraying, bearing wear in the guide wheel, or impending mechanical failure. Upon detecting anomalies, the system triggers a prioritized alert to a maintenance platform, allowing for proactive intervention before a critical component failure occurs, thus enhancing safety and extending device lifespan.
  • Mermaid Diagram:

    sequenceDiagram
        Guide Wheel/Rope->>IoT Acoustic Sensors: Generates/Senses Sound
        IoT Acoustic Sensors-->>Edge Computing Module: Streams Audio Data
        Edge Computing Module->>ML Model: Processes/Analyzes Acoustic Signature
        ML Model->>Edge Computing Module: Detects Anomaly
        Edge Computing Module->>Maintenance Platform: Triggers Alert (Wireless)
        Maintenance Platform->>Technician: Notifies
    

5. The "Inverse" or Failure Mode

• Derivative 10.9: Integrated Shock Absorption for Unexpected Drops

  • Enabling Description: In case of sudden release or uncontrolled drop of the counterweight bearer (4) (e.g., due to rope (31) failure), the "fixed seat" (13) is designed with an integrated hydraulic or pneumatic shock absorption system. This system comprises a deformable chamber with a controlled orifice or a progressive spring damper. If the counterweight bearer falls onto the fixed seat with excessive force (detected by an impact sensor or rapid force change), the shock absorption system deploys, dissipating kinetic energy and preventing damage to the device or injury from rebound. Additionally, the guide wheel (32) is designed with a one-way clutch mechanism that prevents backward rotation of the wheel if the rope becomes slack or breaks, preventing tangling and further uncontrolled motion.
  • Mermaid Diagram:

    stateDiagram-v2
        [*] --> Normal_Operation
        Normal_Operation --> Sudden_Drop : Rope Failure / Uncontrolled Release
        Sudden_Drop --> Impact_Detected
        Impact_Detected --> Deploy_Shock_Absorption : Hydraulic/Pneumatic Damper
        Impact_Detected --> Engage_One_Way_Clutch : Guide Wheel Safety
        Deploy_Shock_Absorption --> Energy_Dissipated
        Energy_Dissipated --> Safe_Resting_State
        Safe_Resting_State --> [*]
    

• Derivative 10.10: Low-Tension Diagnostic Calibration Cycle

  • Enabling Description: The device includes a "low-tension diagnostic calibration cycle" where the "rope" (31) and "guide wheel" (32) are automatically run through a minimal load sequence to assess their integrity and calibrate the 1:1 transmission. In this mode, the counterweight bearer (4) is minimally engaged (e.g., lifted only by a fraction of its total travel from the fixed seat (13)), or a known, light reference weight is temporarily substituted. A precision encoder on the guide wheel (32) and a high-resolution load cell at the leg exercise component (2) measure the actual force transmission ratio. Any deviation from the ideal 1:1 ratio, or excessive friction/slack, triggers a recalibration procedure or flags the need for maintenance. This ensures the constant load feature remains accurate over time without requiring heavy lifting or user interaction for diagnostics.
  • Mermaid Diagram:

    flowchart LR
        A[Start Calibration Cycle] --> B(Minimally Engage Counterweight / Use Reference Weight)
        B --> C(Run Rope/Guide Wheel Sequence)
        C --> D(Measure Force at Leg Exercise Component)
        C --> E(Measure Guide Wheel Rotation)
        D --> F(Compare to Expected 1:1 Ratio)
        E --> F
        F{Deviation Detected?} -->|Yes| G(Trigger Recalibration/Maintenance)
        F{Deviation Detected?} -->|No| H(Calibration Complete - Pass)
        G --> I[Technician Alert]
    

---

Combination Prior Art Scenarios

These scenarios describe how the core concepts of US Patent 12427372, specifically its constant load transfer mechanism, could be combined with existing open-source standards to create obvious or non-novel variations.

1. Open-Source CAD/CAM Integration for Customized Frame Fabrication:

   • Scenario: The support frame (1) and other mechanical components of the leg training device are designed and manufactured using open-source Computer-Aided Design (CAD) software (e.g., FreeCAD, OpenSCAD) and Computer-Aided Manufacturing (CAM) tools (e.g., GRBL for CNC machining).
   • Technical Disclosure: The geometric models for the bottom frame (11), inclined frame (12), and the fixed seat (13) of the support frame are openly published in a standard open-source format (e.g., STEP, STL). Users or small manufacturers can download these models, modify them using FreeCAD to fit custom ergonomic requirements or material specifications (e.g., alternative alloys, composite layups), and then generate G-code using open-source CAM software. This G-code drives open-source controlled CNC machines (e.g., using GRBL firmware) to fabricate the components. This combination renders the specific structural implementation of the support frame and its manufacturing process obvious to a person skilled in the art by leveraging readily available open-source tools for design and fabrication, extending the accessibility and adaptability of the patent's core mechanical structure.
   • Mermaid Diagram:

     flowchart TD
         A[Open-Source CAD Software (FreeCAD)] --> B(Geometric Models of Support Frame)
         B --> C(User Customization / Material Spec)
         C --> D(Open-Source CAM Software)
         D --> E(G-Code Generation)
         E --> F(Open-Source CNC Machine (GRBL))
         F --> G[Fabricated Support Frame Components]
     

2. Telemetry and Data Logging with Open-Source Data Protocols (e.g., MQTT/JSON):

   • Scenario: The leg training device is equipped with sensors to collect performance data (e.g., force, reps, sets, angle of counterweight bearer rotation). This data is transmitted using an open-source messaging protocol like MQTT with data formatted in JSON for interoperability.
   • Technical Disclosure: An embedded microcontroller within the device gathers real-time data from internal sensors, such as load cells on the leg exercise component, rotary encoders on the counterweight bearer (4) to measure its "turn over" angle, and a simple switch to detect the counterweight bearer being lifted from the fixed seat (13). This data is encapsulated into JSON objects and published to an MQTT broker, potentially hosted locally or in the cloud, on a specific topic (e.g., gym/legtrainer/data). Any open-source client application (e.g., a Python script using paho-mqtt or a web app with MQTT.js) can subscribe to this topic, receive the raw, structured exercise data, and process it for analysis, display, or integration into other open-source fitness platforms. This renders the data collection and communication aspect of such a device obvious by combining its mechanical function with standard, open-source IoT communication protocols.
   • Mermaid Diagram:

     sequenceDiagram
         Leg Training Device->>Microcontroller: Collects Sensor Data
         Microcontroller->>JSON Encoder: Formats Data
         JSON Encoder->>MQTT Client: Publishes JSON to Topic
         MQTT Client->>MQTT Broker: Transmits Message
         MQTT Broker->>Open-Source Client App: Delivers Message
         Open-Source Client App->>User: Displays/Processes Data
     

3. Mechanical Design Collaboration via Open-Source Hardware Platforms (e.g., GitHub for Hardware Design):

   • Scenario: The detailed mechanical designs (e.g., link mechanism, adjusting mechanism, guide wheel assembly) of the leg training device are shared and iterated upon using an open-source hardware development platform like GitHub, potentially including designs licensed under CERN-OHL (Open Hardware License).
   • Technical Disclosure: The CAD models (e.g., SolidWorks, Fusion 360 files or their open equivalents like FreeCAD files) for components like the first rod (221), second rod (222), bolt (223), adjusting disc (231), rotating shaft (233), and guide wheel (32) are uploaded to a public GitHub repository. This repository also includes build instructions, bills of materials, and potentially firmware for any embedded microcontrollers. Mechanical engineers and hobbyists worldwide can fork the repository, propose improvements to optimize material usage, simplify manufacturing, or integrate alternative open-source components (e.g., different open-source bearing designs or fastening methods). This collaborative, version-controlled approach to hardware design, using open-source licenses, makes specific mechanical implementations and improvements highly transparent and openly accessible, thus establishing broad prior art for mechanical variations and iterative enhancements.
   • Mermaid Diagram:

     gitGraph
         commit id: "Initial Design Commit"
         branch develop
         commit id: "Linkage Optimization"
         commit id: "Guide Wheel Refinement"
         checkout main
         merge develop id: "Release V1.0"
         branch feature/material_substitution
         commit id: "Polymer Rod Design"
         checkout develop
         commit id: "Adjusting Disc Enhancement"
         checkout feature/material_substitution
         merge develop id: "Integrate Adjusting Disc"
         checkout main
         merge feature/material_substitution id: "Release V1.1 (Open Hardware)"