Prior art

For US Patent 8,132,515, titled "Railroad gondola car structure and mechanism therefor," the following prior art documents are cited. This analysis focuses on potential anticipation under 35 U.S.C. § 102 based on the provided patent text and the abstracts of the cited references.

Most Relevant Prior Art for US8132515

1. U.S. Patent 4,250,814 (Stark et al.)

   • Full Citation: U.S. Patent 4,250,814, "Hopper car with pivoting doors and operating mechanism", issued February 17, 1981, to Stark et al., assigned to Ortner Freight Car Company.
   • Publication/Filing Date: Publication Date: 1981-02-17; Filing Date: 1979-05-18.
   • Brief Description: This patent describes a hopper car with bottom-dumping pivoting doors, specifically longitudinally hinged doors, and an operating mechanism including an air cylinder and linkage system to move these doors between open and closed positions.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad aspects): These claims generally cover a railroad hopper car with a bottom discharge door, a linkage connected to the door, and a drive (actuating cylinder) to move the door. Stark et al. clearly teaches the fundamental concept of a hopper car with such features.
     • Claim 1 (linkage and drive orientation): "a linkage connected to the door, the linkage being oriented lengthwise with respect to the car. A drive connected to the linkage. The drive is operable to move the linkage and thereby to urge the door to a closed position." Stark et al. describes a system with an air cylinder and linkage for door operation, which is oriented to act lengthwise.
     • Claim 27 (actuating cylinder and linkage): "A door operating linkage is connected to the gate, the door operating linkage being oriented lengthwise with respect to the car. An actuating cylinder connected to drive the door operating linkage, the actuating cylinder also being oriented to act lengthwise with respect to the car, the actuating cylinder having an axis of reciprocation." This also broadly describes elements found in Stark et al.
     • Context: US8132515 itself references Stark et al. as prior art demonstrating cars with longitudinal doors, indicating that the general concept of such door operation is known.

2. U.S. Patent 3,800,711 (Tuttle et al.)

   • Full Citation: U.S. Patent 3,800,711, "Hopper car door operating mechanism", issued April 2, 1974, to Tuttle et al., assigned to Ortner Freight Car Company.
   • Publication/Filing Date: Publication Date: 1974-04-02; Filing Date: 1972-10-18.
   • Brief Description: This patent details a hopper car door operating mechanism that employs an air cylinder to drive a lever system, specifically designed for longitudinally hinged doors. It focuses on a compact linkage arrangement for operating multiple doors.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad aspects): Similar to Stark et al., Tuttle et al. discloses a hopper car with bottom discharge doors and a mechanism (linkage and air cylinder drive) for their operation, thus potentially anticipating broad claims in 8132515 relating to these general components.
     • Context: US8132515 also cites Tuttle et al. as an example of prior art with longitudinal doors.

3. U.S. Patent 4,828,321 (Peterson)

   • Full Citation: U.S. Patent 4,828,321, "Mine car door operating mechanism", issued May 9, 1989, to Peterson, assigned to Thrall Car Manufacturing Company.
   • Publication/Filing Date: Publication Date: 1989-05-09; Filing Date: 1988-06-20.
   • Brief Description: This patent describes a robust door operating mechanism for bottom discharge doors of a mine car, utilizing an air cylinder and a system of levers and links for efficient and compact operation.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad aspects): These claims covering a hopper car with a bottom discharge, a door, a linkage, and a drive are broadly taught by Peterson's patent for mine cars.

4. U.S. Patent 3,459,146 (Bachman)

   • Full Citation: U.S. Patent 3,459,146, "Railway hopper car", issued August 5, 1969, to Bachman, assigned to The Youngstown Steel Door Company.
   • Publication/Filing Date: Publication Date: 1969-08-05; Filing Date: 1967-08-11.
   • Brief Description: This patent describes a railway hopper car structure with multiple hoppers and bottom discharge gates, focusing on the overall car body and discharge opening design.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad aspects): The general concept of a railway hopper car with bottom discharge and associated operating mechanisms is present in Bachman.
     • Claims 56-65 (car body structure): These claims of US8132515 relate to the car's end sections, draft sill, main bolster, shear plate, and arrangement of posts and machinery space. Bachman's patent, focusing on railway hopper car structure, could potentially anticipate some of these broader structural elements.

5. U.S. Patent Application Publication 2008/0000392 A1 (Hinkson)

   • Full Citation: U.S. Patent Application Publication 2008/0000392 A1, "Railroad hopper car with improved door operating mechanism", published January 3, 2008, by Daniel G. G. Hinkson, assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2008-01-03; Filing Date: 2007-06-29.
   • Brief Description: This publication describes a railroad hopper car featuring an improved door operating mechanism, including an actuating cylinder and a linkage system for bottom discharge doors, with an aim for a compact installation.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism and linkage): Given the same assignee (National Steel Car Limited) and a very similar subject matter and timeframe, this reference is highly relevant. It is likely to anticipate many features related to the general arrangement of a lengthwise-oriented linkage and cylinder, and efforts towards compact installations. Specific distinctions in US8132515 like the "inclined" actuating cylinder (Claim 27), the "bifurcated lever straddling the drive" (Claim 20), or the specific drag link motion parallel to the slope sheet (Claim 1) would need careful comparison.

6. U.S. Patent Application Publication 2007/0119339 A1 (Hinkson)

   • Full Citation: U.S. Patent Application Publication 2007/0119339 A1, "Hopper car door operating mechanism", published May 31, 2007, by Daniel G. G. Hinkson, assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2007-05-31; Filing Date: 2006-11-28.
   • Brief Description: This publication describes a hopper car door operating mechanism that uses an actuating cylinder and a lever system for discharge doors, with a focus on improvements to the mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism and linkage): Similar to the other Hinkson/National Steel Car publications, this document is highly relevant to claims concerning the door operating linkage and actuating cylinder. It likely anticipates the broader aspects, requiring US8132515 to rely on specific design choices for novelty, such as the exact kinematics of the linkage or the particular over-center and secondary lock mechanisms.

7. U.S. Patent Application Publication 2008/0098934 A1 (Daugherty)

   • Full Citation: U.S. Patent Application Publication 2008/0098934 A1, "Bottom discharge arrangement for a rail car", published May 1, 2008, by Roger R. Daugherty, assigned to Johnstown America Corporation.
   • Publication/Filing Date: Publication Date: 2008-05-01; Filing Date: 2006-10-27.
   • Brief Description: This publication describes a bottom discharge arrangement for a rail car, including a door assembly that pivots about a longitudinal axis and its operating mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad aspects): This document teaches a bottom discharge door assembly and an operating mechanism, which could anticipate the general claims of US8132515 that describe these fundamental components.

8. U.S. Patent Application Publication 2008/0184915 A1 (Hinkson)

   • Full Citation: U.S. Patent Application Publication 2008/0184915 A1, "Bottom discharge arrangement for a rail car", published August 7, 2008, by Daniel G. G. Hinkson, assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2008-08-07; Filing Date: 2007-06-29.
   • Brief Description: This publication describes a bottom discharge arrangement for a rail car, with a focus on its door operating mechanism. It is another publication from the same assignee, indicating a continued line of research and development.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism): Similar to the other Hinkson/National Steel Car references, this is likely to anticipate many claims related to the door operating linkage and actuating cylinder, requiring careful analysis of the specific distinctions detailed in US8132515.

9. U.S. Patent Application Publication 2008/0229969 A1 (Hinkson)

   • Full Citation: U.S. Patent Application Publication 2008/0229969 A1, "Railroad hopper car", published September 25, 2008, by Daniel G. G. Hinkson, assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2008-09-25; Filing Date: 2007-06-29.
   • Brief Description: This publication describes a railroad hopper car, likely encompassing structural features and potentially aspects of its discharge mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism) and Claims 56-65 (structural features): Being another Hinkson/National Steel Car publication, it is expected to address various elements of hopper car design, including door operating mechanisms and structural details. Specific claims in US8132515 related to the "machinery space" or specific arrangements of components within the car end would need to be compared.

10. U.S. Patent Application Publication 2008/0302271 A1 (Brost)

    • Full Citation: U.S. Patent Application Publication 2008/0302271 A1, "Railway car with an improved body side construction", published December 11, 2008, by Robert S. E. Brost, assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2008-12-11; Filing Date: 2007-06-29.
    • Brief Description: This publication is directed towards an improved side body construction for a railway car, which directly relates to structural elements of a hopper car's sidewall.
    • Potential Anticipated Claims of US8132515:
      • Claims 36-45 (sidewall construction): These claims of US8132515 specifically describe the sidewall structure, including a stiffener with portions laterally outboard and inboard of the sidewall regions, and a side sheet transition. Brost's publication, addressing improved body side construction, is highly likely to anticipate elements of these claims, necessitating a detailed comparison of the specific stiffener and side sheet arrangement.

11. U.S. Patent Application Publication 2009/0007821 A1 (Hinkson)

    • Full Citation: U.S. Patent Application Publication 2009/0007821 A1, "Bottom discharge arrangement for a rail car", published January 8, 2009, by Daniel G. G. Hinkson, assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2009-01-08; Filing Date: 2008-07-07.
    • Brief Description: This publication describes a bottom discharge arrangement for a rail car, focusing on the door operating mechanism and the door structure itself.
    • Potential Anticipated Claims of US8132515:
      • Claims 1-26, 36-55 (door operating mechanism and door structure): Another Hinkson/National Steel Car publication concerning bottom discharge. It is highly probable that many claims in 8132515 relating to the door operating linkage and actuating cylinder will find relevant teaching in this document.

12. U.S. Patent Application Publication 2009/0158971 A1 (Hinkson)

    • Full Citation: U.S. Patent Application Publication 2009/0158971 A1, "Railroad freight car body", published June 25, 2009, by Daniel G. G. Hinkson, assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2009-06-25; Filing Date: 2008-12-17.
    • Brief Description: This publication describes a railroad freight car body, with likely emphasis on its structural details, including the underframe and draft sill.
    • Potential Anticipated Claims of US8132515:
      • Claims 56-65 (end sections and machinery space) and Claims 66-74 (draft sill structure): This publication is likely to be highly relevant to the structural claims of US8132515, particularly those describing the "short draft sill length" (Claims 66-74), "removable draft gear carrier plate," or the "aperture formed in the shear plate" for draft gear installation. Close examination would be needed to determine if the specific dimensions and configurations of these components are anticipated.

13. Canadian Patent Application 2,254,332 A1 (Snelgrove et al.)

    • Full Citation: Canadian Patent Application 2,254,332 A1, "Bottom discharge gate for a hopper car", published May 28, 1999, by William F. Snelgrove et al., assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 1999-05-28; Filing Date: 1998-11-20.
    • Brief Description: This patent application describes a bottom discharge gate system for a hopper car, likely including both the gate design and its associated operating mechanism.
    • Potential Anticipated Claims of US8132515:
      • Claims 1, 20, 27, 36, 46 (bottom discharge and operating linkage): As an earlier Canadian application by the same assignee on the subject of "bottom discharge gate for a hopper car," this document is highly relevant to the general concepts of US8132515's claims concerning the bottom discharge governor, door assembly, and basic linkage.

14. Canadian Patent Application 2,324,796 A1 (Snelgrove et al.)

    • Full Citation: Canadian Patent Application 2,324,796 A1, "Hopper car discharge gate operating mechanism", published May 17, 2001, by William F. Snelgrove et al., assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2001-05-17; Filing Date: 1999-11-16.
    • Brief Description: This patent application is specifically directed to a discharge gate operating mechanism for a hopper car, providing further insight into the assignee's prior work in this domain.
    • Potential Anticipated Claims of US8132515:
      • Claims 1-26, 36-55 (door operating mechanism): Similar to CA2254332A1, this earlier Canadian application from the same assignee is highly likely to anticipate the broader claims related to the door operating linkage and actuating cylinder. Specific distinctions claimed in US8132515, such as the exact motion of the drag link, the inclined actuating cylinder, the over-center lock, or the secondary lock, would be crucial for establishing novelty.

Disclaimer: This analysis provides a preliminary assessment of potential anticipation based on available abstracts and general descriptions. A definitive determination of anticipation under 35 U.S.C. § 102 would require a thorough claim-by-claim comparison with the full disclosures of each prior art document, including drawings and detailed specifications.### Most Relevant Prior Art for US8132515

This section identifies prior art documents cited by US Patent 8,132,515 and assesses which claims they might potentially anticipate under 35 U.S.C. § 102. The analysis is based on the information provided in the US8132515 patent text and the abstracts of the cited references.

1. U.S. Patent 4,250,814 to Stark et al.

   • Full Citation: U.S. Patent 4,250,814, titled "Hopper car with pivoting doors and operating mechanism," issued February 17, 1981, to Stark et al., and assigned to Ortner Freight Car Company.
   • Publication/Filing Date: Publication Date: 1981-02-17; Filing Date: 1979-05-18.
   • Brief Description: This patent discloses a hopper car equipped with pivoting doors for bottom discharge, specifically longitudinally hinged doors. It also describes an operating mechanism that uses an air cylinder and a linkage system to move these doors between open and closed positions.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad concepts): These claims broadly describe a railroad hopper car with a bottom discharge door, a linkage connected to the door, and a drive (actuating cylinder) to operate the door. Stark et al. teaches these fundamental components and their function in a hopper car.
     • Claim 1 (linkage and drive orientation): The claim "a linkage connected to the door, the linkage being oriented lengthwise with respect to the car. A drive connected to the linkage. The drive is operable to move the linkage and thereby to urge the door to a closed position" is broadly covered by the air cylinder and linkage system described by Stark et al., which operates longitudinally hinged doors.
     • Claim 27 (actuating cylinder and linkage): The general concept of "A door operating linkage is connected to the gate... An actuating cylinder connected to drive the door operating linkage, the actuating cylinder also being oriented to act lengthwise with respect to the car, the actuating cylinder having an axis of reciprocation" aligns with the system presented in Stark et al.
     • Rationale: US8132515 explicitly refers to U.S. Pat. No. 4,250,814 as prior art related to "cars with longitudinal doors" in its background section, acknowledging the existence of such systems.

2. U.S. Patent 3,800,711 to Tuttle et al.

   • Full Citation: U.S. Patent 3,800,711, titled "Hopper car door operating mechanism," issued April 2, 1974, to Tuttle et al., and assigned to Ortner Freight Car Company.
   • Publication/Filing Date: Publication Date: 1974-04-02; Filing Date: 1972-10-18.
   • Brief Description: This patent focuses on a hopper car door operating mechanism that employs an air cylinder to drive a lever system. It is designed for longitudinally hinged doors and emphasizes a compact linkage arrangement for opening and closing multiple doors.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad concepts): Similar to Stark et al., Tuttle et al. discloses a hopper car with bottom discharge doors and a mechanism (linkage and air cylinder drive) to operate them, potentially anticipating broad claims in 8132515 that define these core components.
     • Claim 1 (linkage and drive orientation): The description of a linkage connected to a door, oriented lengthwise with respect to the car, and a drive operable to move the linkage to close the door, is found in Tuttle et al.
     • Claim 27 (actuating cylinder and linkage): The presence of a door operating linkage oriented lengthwise and an actuating cylinder acting lengthwise with an axis of reciprocation is broadly consistent with Tuttle et al.
     • Rationale: US8132515 also explicitly references U.S. Pat. No. 3,800,711 in its background, confirming its relevance as prior art for longitudinal door mechanisms.

3. U.S. Patent 4,828,321 to Peterson

   • Full Citation: U.S. Patent 4,828,321, titled "Mine car door operating mechanism," issued May 9, 1989, to Peterson, and assigned to Thrall Car Manufacturing Company.
   • Publication/Filing Date: Publication Date: 1989-05-09; Filing Date: 1988-06-20.
   • Brief Description: This patent describes a door operating mechanism for bottom discharge doors of a mine car, which uses an air cylinder and a system of levers and links. It emphasizes a robust and compact design for operating multiple doors.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad concepts): These claims broadly cover a hopper car (mine cars are a type of hopper car) with bottom discharge, a door, a linkage, and a drive. Peterson's patent clearly discloses such a system.

4. U.S. Patent 3,459,146 to Bachman

   • Full Citation: U.S. Patent 3,459,146, titled "Railway hopper car," issued August 5, 1969, to Bachman, and assigned to The Youngstown Steel Door Company.
   • Publication/Filing Date: Publication Date: 1969-08-05; Filing Date: 1967-08-11.
   • Brief Description: This patent describes a railway hopper car structure featuring multiple hoppers and bottom discharge gates, with a focus on the overall car body design and the configuration of the discharge openings.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad concepts): Bachman's patent provides general teaching of a railway hopper car with bottom discharge and a mechanism for operating the doors, thus potentially anticipating the broad inventive steps of these claims.
     • Claims 56-65 (car body structure): These claims of US8132515 relate to the car's end sections, draft sill, main bolster, shear plate, and the arrangement of posts and machinery space. Bachman's structural focus on hopper cars could anticipate some of these broader structural elements.

5. U.S. Patent Application Publication 2008/0000392 A1 to Hinkson

   • Full Citation: U.S. Patent Application Publication 2008/0000392 A1, titled "Railroad hopper car with improved door operating mechanism," published January 3, 2008, by Daniel G. G. Hinkson, and assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2008-01-03; Filing Date: 2007-06-29.
   • Brief Description: This publication describes a railroad hopper car with an improved door operating mechanism, incorporating an actuating cylinder and a linkage system for bottom discharge doors, aiming for a compact installation.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism and linkage): Given the common assignee (National Steel Car Limited) and the similar subject matter and timeframe, this reference is highly relevant. It is likely to anticipate many features related to the general arrangement of a lengthwise-oriented linkage and cylinder, and designs for compact installations. Distinctions in US8132515, such as the "inclined" actuating cylinder (Claim 27), the "bifurcated lever straddling the drive" (Claim 20), or the specific drag link motion parallel to the slope sheet (Claim 1), would be critical for differentiating the invention.

6. U.S. Patent Application Publication 2007/0119339 A1 to Hinkson

   • Full Citation: U.S. Patent Application Publication 2007/0119339 A1, titled "Hopper car door operating mechanism," published May 31, 2007, by Daniel G. G. Hinkson, and assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2007-05-31; Filing Date: 2006-11-28.
   • Brief Description: This publication describes a hopper car door operating mechanism that employs an actuating cylinder and a lever system for discharge doors, with an emphasis on improvements to the mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism and linkage): As another publication by the same assignee on improved door operating mechanisms, this document is highly relevant. It is likely to anticipate the broader aspects of claims related to the door operating linkage and actuating cylinder.

7. U.S. Patent Application Publication 2008/0098934 A1 to Daugherty

   • Full Citation: U.S. Patent Application Publication 2008/0098934 A1, titled "Bottom discharge arrangement for a rail car," published May 1, 2008, by Roger R. Daugherty, and assigned to Johnstown America Corporation.
   • Publication/Filing Date: Publication Date: 2008-05-01; Filing Date: 2006-10-27.
   • Brief Description: This publication details a bottom discharge arrangement for a rail car, including a door assembly that pivots about a longitudinal axis and its associated operating mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1, 20, 27, 36 (broad concepts): This document teaches a bottom discharge door assembly and an operating mechanism, which could anticipate the general claims of US8132515 that describe these fundamental components.

8. U.S. Patent Application Publication 2008/0184915 A1 to Hinkson

   • Full Citation: U.S. Patent Application Publication 2008/0184915 A1, titled "Bottom discharge arrangement for a rail car," published August 7, 2008, by Daniel G. G. Hinkson, and assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2008-08-07; Filing Date: 2007-06-29.
   • Brief Description: This publication describes a bottom discharge arrangement for a rail car, with a specific focus on its door operating mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism): As another Hinkson/National Steel Car publication, this reference is highly relevant and likely anticipates many claims relating to the door operating linkage and actuating cylinder.

9. U.S. Patent Application Publication 2008/0229969 A1 to Hinkson

   • Full Citation: U.S. Patent Application Publication 2008/0229969 A1, titled "Railroad hopper car," published September 25, 2008, by Daniel G. G. Hinkson, and assigned to National Steel Car Limited.
   • Publication/Filing Date: Publication Date: 2008-09-25; Filing Date: 2007-06-29.
   • Brief Description: This publication describes a railroad hopper car, likely encompassing structural features and potentially details of its discharge mechanism.
   • Potential Anticipated Claims of US8132515:
     • Claims 1-26, 36-55 (door operating mechanism) and Claims 56-65 (structural features): This publication is expected to cover various aspects of hopper car design, including door operating mechanisms and structural details, making it relevant to many claims in US8132515.

10. U.S. Patent Application Publication 2008/0302271 A1 to Brost

    • Full Citation: U.S. Patent Application Publication 2008/0302271 A1, titled "Railway car with an improved body side construction," published December 11, 2008, by Robert S. E. Brost, and assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2008-12-11; Filing Date: 2007-06-29.
    • Brief Description: This publication focuses on an improved body side construction for a railway car, directly addressing structural elements relevant to a hopper car's sidewall.
    • Potential Anticipated Claims of US8132515:
      • Claims 36-45 (sidewall construction): These claims in US8132515 specifically describe the sidewall structure, including the arrangement of stiffeners and side sheet transitions. Brost's publication, directly pertaining to improved body side construction, is highly likely to anticipate elements of these claims.

11. U.S. Patent Application Publication 2009/0007821 A1 to Hinkson

    • Full Citation: U.S. Patent Application Publication 2009/0007821 A1, titled "Bottom discharge arrangement for a rail car," published January 8, 2009, by Daniel G. G. Hinkson, and assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2009-01-08; Filing Date: 2008-07-07.
    • Brief Description: This publication describes a bottom discharge arrangement for a rail car, focusing on the door operating mechanism and the structure of the door itself.
    • Potential Anticipated Claims of US8132515:
      • Claims 1-26, 36-55 (door operating mechanism and door structure): As another Hinkson/National Steel Car publication on bottom discharge, it is highly probable that many claims in 8132515 related to the door operating linkage and actuating cylinder will find relevant teaching in this document.

12. U.S. Patent Application Publication 2009/0158971 A1 to Hinkson

    • Full Citation: U.S. Patent Application Publication 2009/0158971 A1, titled "Railroad freight car body," published June 25, 2009, by Daniel G. G. Hinkson, and assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2009-06-25; Filing Date: 2008-12-17.
    • Brief Description: This publication describes a railroad freight car body, likely with structural details relevant to the underframe and draft sill.
    • Potential Anticipated Claims of US8132515:
      • Claims 56-65 (end sections and machinery space) and Claims 66-74 (draft sill structure): This publication is likely highly relevant to the structural claims of US8132515, particularly those describing the "short draft sill length," "removable draft gear carrier plate," and features related to draft gear installation.

13. Canadian Patent Application 2,254,332 A1 to Snelgrove et al.

    • Full Citation: Canadian Patent Application 2,254,332 A1, titled "Bottom discharge gate for a hopper car," published May 28, 1999, by William F. Snelgrove et al., and assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 1999-05-28; Filing Date: 1998-11-20.
    • Brief Description: This patent application describes a bottom discharge gate system for a hopper car, likely encompassing both the gate design and its associated operating mechanism.
    • Potential Anticipated Claims of US8132515:
      • Claims 1, 20, 27, 36, 46 (bottom discharge and operating linkage): As an earlier Canadian application by the same assignee concerning a "bottom discharge gate for a hopper car," this document is highly relevant to the general concepts covered in US8132515's claims concerning the bottom discharge governor, door assembly, and basic linkage.

14. Canadian Patent Application 2,324,796 A1 to Snelgrove et al.

    • Full Citation: Canadian Patent Application 2,324,796 A1, titled "Hopper car discharge gate operating mechanism," published May 17, 2001, by William F. Snelgrove et al., and assigned to National Steel Car Limited.
    • Publication/Filing Date: Publication Date: 2001-05-17; Filing Date: 1999-11-16.
    • Brief Description: This patent application specifically describes a discharge gate operating mechanism for a hopper car.
    • Potential Anticipated Claims of US8132515:
      • Claims 1-26, 36-55 (door operating mechanism): Similar to CA2254332A1, this earlier Canadian application from the same assignee, specifically on the "operating mechanism," is highly likely to anticipate the broader claims related to the door operating linkage and actuating cylinder. Specific distinguishing features of US8132515, such as the inclined actuating cylinder, the over-center lock, or the secondary lock, would be crucial for establishing novelty.

Note on Anticipation:
The older US patents (Stark, Tuttle, Peterson, Bachman) primarily represent the general state of the art for railroad hopper cars and their door operating mechanisms. They establish that the basic components (doors, linkages, pneumatic drives) were well-known. The more recent US and Canadian patent application publications by National Steel Car Limited (Hinkson, Brost, Snelgrove) are particularly relevant because they originate from the same assignee and fall within a similar technological development timeline, suggesting they may represent earlier iterations or related developments of the inventions claimed in US8132515. Therefore, claims in US8132515 are most likely to distinguish themselves from this more recent prior art through specific structural arrangements, dimensions, and unique operational features (e.g., the inclined actuating cylinder, the bifurcated lever, the precise motion of the drag link, the specific secondary lock mechanism, or the details of the "unobstructed machinery space" and "short draft sill" configuration). A definitive determination of anticipation would require a thorough, claim-by-claim comparison against the full disclosure of each cited document.