Obviousness

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

A patent claim is 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). The analysis considers the scope and content of the prior art, differences between the prior art and the claimed invention, the level of ordinary skill in the art, and any secondary considerations of non-obviousness. The Supreme Court case KSR International Co. v. Teleflex Inc. established a more flexible approach to obviousness, emphasizing that a teaching, suggestion, or motivation (TSM) is not always required to combine prior art references, and predictable results from established functions in the prior art can be sufficient to prove obviousness.

The patent US8860337 describes linear vibration modules (LVMs) and linear-resonant vibration modules (LRVMs) that produce vibrational forces through the linear oscillation of a weight or member driven by rapidly alternating electromagnet polarity. LRVMs specifically use feedback control to maintain operation at or near the resonant frequency. Both types are designed to achieve a wide range of amplitude/frequency combinations.

Below, we analyze the obviousness of the independent claims of US8860337 by identifying combinations of prior art that would render them obvious and explaining the motivation for such combinations.

Claim 1: Linear Vibration Module with Paramagnetic Flux Paths

Claim 1 describes a linear vibration module with a housing, a moveable component, a power supply, user-input features, a driving component for linear oscillation, a control component to adjust frequency and amplitude based on user input, and "flux paths comprising a paramagnetic material that is shaped and positioned to reduce the reluctance of one or more magnetic circuits within the linear vibration module."

Prior Art Considerations:

• Linear vibration motors employing electromagnets for driving a moveable mass are well-known in the prior art. For example, US20100052578 describes a subminiature linear vibrator with a stationary body including a ring-shaped field coil and a movable body with a ring-shaped permanent magnet, wherein the permanent magnet is disposed adjacent to the field coil for linear movement. US20170182517A9 also discusses linear motion vibration actuators where magnetic forces are generated between a base and a moving magnet to create acceleration and motion.
• The concept of reducing magnetic reluctance and increasing efficiency in magnetic circuits through the use of paramagnetic materials is a fundamental principle in electromagnetism. The patent itself explicitly states that "paramagnetic materials provide a lower-resistance path for magnetic flux, providing that they have adequate permeability and size to avoid saturation" and that their addition "provides a more efficient linear vibration module."
• Prior art exists that discusses reducing magnetic flux leakage in linear vibration motors to improve performance. For instance, a 2020 paper by Jiang et al. discusses three new designs for linear vibration motors aimed at reducing magnetic flux leakage, achieving significant reductions while maintaining performance. While this specific reference may be post-priority date for US8860337, the underlying problem of magnetic flux leakage and the general goal of improving efficiency in magnetic systems were well-understood.

Obviousness Argument:
A PHOSITA, aware of existing linear vibration modules (e.g., US20100052578, US20170182517A9) and seeking to improve their efficiency by reducing magnetic reluctance, would have been motivated to incorporate paramagnetic flux paths into the magnetic circuits. The patent itself teaches that paramagnetic materials provide a lower-resistance path for magnetic flux, leading to a more efficient linear vibration module. This motivation would be further supported by the general engineering principle of optimizing magnetic circuits for efficiency, which is a common design consideration for any electromagnetic device. The specific shaping and positioning of the paramagnetic material would be a matter of routine design choice for a PHOSITA to achieve the desired reduction in reluctance, based on known principles of magnetic field shaping and material properties. The combination of a known linear vibration module with well-understood techniques for improving magnetic circuit efficiency would be obvious.

Claim 2: Linear Vibration Module with Simultaneous Multi-Frequency Oscillation

Claim 2 describes a linear vibration module that includes a housing, a moveable component, a power supply, user-input features, a driving component for linear oscillation, and a control component that "drives simultaneous oscillation of the moveable component at two or more frequencies to generate complex vibration modes."

Prior Art Considerations:

• Linear vibration modules with control components capable of driving the moveable component are described in the patent (e.g., FIG. 6 showing a CPU controlling an H-bridge switch to alternate current direction in a coil).
• The concept of generating complex vibration modes by combining multiple frequencies is known in the art of vibration control. For example, US8860337 itself illustrates "interesting vibrational modes produced by driving a linear-resonant vibration module simultaneously at two different frequencies," including a primary oscillation frequency modulated by a modulating frequency (FIG. 22B) and a beat-wave form from two driving frequencies (FIG. 23).
• Technologies for controlling and tracking multiple resonant modes in mechanical resonators using systems like phase-locked loop (PLL) arrays have been described. For example, MIT Technology Licensing Office discusses "simultaneous oscillation and frequency tracking of multiple resonances via digitally implemented phase-locked loop array" for controlling mechanical resonators.
• Studies on multi-frequency vibration suppression also exist, such as the use of an inertial piezoelectric actuator in indoor substations to address complex vibration spectra arising from dynamic operations. Similarly, an amplitude-modulating vibrator for predictive maintenance modeling is described, capable of creating vibrations at different frequencies and magnitudes.

Obviousness Argument:
A PHOSITA, aware of linear vibration modules with control capabilities (e.g., as shown in FIG. 6 of US8860337), and motivated to create more varied or complex haptic feedback or vibration patterns, would have found it obvious to drive the moveable component simultaneously at two or more frequencies. The patent itself demonstrates the desirability and feasibility of such multi-frequency driving to produce "low-frequency pulses of high-frequency vibration" and "lower-frequency beat-wave form[s]". The use of control components (such as microprocessors, as described in US8860337) to generate different frequencies is a known technique in electronic control systems. Given the existing knowledge of combining frequencies to produce complex waveforms in various fields (e.g., sound synthesis, signal processing), applying this principle to linear vibration modules to achieve diverse vibration modes would be a straightforward extension for a PHOSITA. The MIT reference to simultaneous oscillation and frequency tracking of multiple resonances via digitally implemented phase-locked loop array further exemplifies the known techniques for achieving multi-frequency operation in mechanical systems.

Claim 4: Linear Vibration Module with Independent Amplitude and Frequency Control

Claim 4 describes a linear vibration module with a housing, a moveable component, a power supply, user-input features, a driving component for linear oscillation, and a control component that causes the moveable component to oscillate at a frequency and an amplitude that are "independently specified by user input received from the user-input features."

Prior Art Considerations:

• The general concept of user-input controlled vibration devices is fundamental to many appliances (e.g., pagers, electric toothbrushes).
• US8860337 itself describes linear vibration modules where "the vibration amplitude and vibration frequency can be independently controlled by a user through user-input features, including buttons, sliders, and other types of user-input features." It also discusses replacing a microprocessor with a simpler oscillator circuit and additional control circuitry, where a variable-frequency oscillator can be controlled by user input to adjust frequency, and another input feature allows the user to control current or duty cycle to adjust amplitude. This essentially describes independent control of frequency and amplitude.
• The patent further illustrates how a linear vibration module with user-input-controlled variable frequency and variable amplitude can access a much broader range of amplitude/frequency combinations than fixed-amplitude or fixed-frequency devices (FIG. 20).
• The abstract of US20170182517A9 mentions that varying parameters in linear motion vibration actuators produces a broad range of haptic sensations, and that amplitude and frequency of beating force are variable. This implies a level of control over both parameters.

Obviousness Argument:
A PHOSITA, seeking to provide enhanced user customization and functionality in linear vibration modules, would have found it obvious to implement independent user control over both oscillation frequency and amplitude. The patent explicitly acknowledges that prior art unbalanced electric motors and resonating motors generally operate at either a fixed amplitude or a fixed frequency, highlighting a problem that the claimed invention aims to solve. The motivation to overcome these limitations and provide greater user control is clear. Given that both frequency (e.g., by controlling the rate of current reversal in an electromagnet, as described in the patent) and amplitude (e.g., by controlling the current or duty cycle supplied to the driving component, as also described in the patent) are independently adjustable parameters in linear vibration systems, it would be a matter of routine engineering to connect these controls to separate user-input features. The patent itself lays out this combination as a straightforward way to expand the accessible amplitude/frequency space.

Claim 5: Linear Vibration Module with Elastomeric Bristles

Claim 5 describes a linear vibration module including a housing, a moveable component, a power supply, user-input features, a driving component for linear oscillation, a control component to adjust frequency and amplitude based on user input, and "elastomeric bristles used to transfer vibration from the linear vibration module to a surface."

Prior Art Considerations:

• Linear vibration modules producing vibrational output are the core of the invention. US8860337 describes various linear vibration modules, including one that extends into a massage arm with a massage-foot member for massaging human skin or other substrates.
• The patent specifically enhances this massage foot to include "elastomer bristles 1802-1805 to transfer the linear oscillation of the massage foot to human skin or another substrate." It states that these bristles "allow transmission of vibration to a surface even at low operational powers, when a rigid or even semi-compliant massage foot would instead simply stop moving for inability to overcome frictional forces." This highlights a known benefit of using elastomeric bristles for vibration transfer.
• Prior art in robotics and haptics demonstrates the use of bristles for interaction with surfaces. For instance, a paper by Cao et al. discusses a robot with soft bristles driven by vertical vibration, where the bristles' deflection contributes to movement. Another reference from NASA discusses an actuator device with an elastomeric film and a frame that provides an elastic restoring force.
• The general use of elastomeric materials for cushioning, gripping, and tactile feedback in various devices is widespread.

Obviousness Argument:
A PHOSITA, designing a linear vibration module intended to transfer vibrations to a surface (such as human skin for massage or tactile feedback), and seeking to improve the efficiency or effectiveness of this transfer, would have been motivated to incorporate elastomeric bristles. The patent itself identifies the advantage of elastomeric bristles in transferring vibration even at low operational powers by overcoming frictional forces. Given that vibration devices are often used for tactile feedback or massage, and bristles are commonly used in various applications to interact with surfaces (e.g., brushes), the combination of a linear vibration module with elastomeric bristles to enhance vibration transfer would be an obvious design choice. This is further supported by the general knowledge in the art regarding the properties of elastomeric materials for compliant contact and vibration transmission, and the use of bristles in related fields like robotics for surface interaction.