Linear actuator and method of operation

Abstract

The linear actuator includes a mass mass movably mounted in a linear displacement path, the mass mass having a magnetic segment, a drive force generator configured to selectively impart an acceleration to the mass mass along a path direction of the linear displacement path, and a reaction force path that generates a return force when the mass mass is displaced from a rest position, the return force being directed toward the rest position along the path direction of the linear displacement path, the return force having an amplitude that varies as a function of the position of the mass mass in the linear displacement path according to a force response curve, the reaction force path including a permanent magnetic force element disposed adjacent to the linear displacement path in a direction transverse to the linear displacement path and magnetically coupled to the magnetic segment.

Description

Background Art

[0001] Many types of linear actuators exist. A linear actuator typically includes some form of mass that can reciprocate along a linear path. The linear path is typically straight, but there may be some cases where the linear path is curved. Some linear actuators, for example tactile actuators, are configured to generate acceleration force. Perhaps the best-known example of acceleration force is vibration, but many other types or sequences of acceleration force are possible. Such a linear actuator can have a reaction path, for example a path that causes a gradual change in force in response to movement of the mass away from an equilibrium position or zone, and a driving force generator that can be independent of the reaction path. Excluding the forces exerted on the mass by the driving force generator and the reaction path, and typically also a minimized amount of friction, the mass can move freely linearly, for example by being movably mounted along some form of linear guide. While existing linear actuators have been satisfactory to a certain extent, there is always room for improvement. Prior Art Documents Patent Documents

[0002] Patent Document 1 European Patent Application Publication No. 0594757 Patent Document 2 United States Patent Application Publication No. 2019 / 0050056 Summary of the Invention Problem to be Solved by the Invention

[0003] The reaction force path can originate from, for example, one or more springs, one or more magnets (in combination with a magnetized mass), one or more stops, or a combination of springs, stops, and magnets. The driving force generator can originate from, for example, electrically driving an electromagnet (coil) if the mass is magnetized. Different types of force elements, such as magnets and springs, may have their own advantages and disadvantages to each other, and the choice of using one or the other may depend on the specifics of a given embodiment.

[0004] In the case of linear actuator-type haptic actuators, it may be desirable that the force response curve generated by the reaction path exhibits a return force when the mass is moved away from the equilibrium position or zone. Furthermore, in scenarios where the maximum amount of inertia is imparted to the mass by the drive force generator, it may be desirable that the reaction path be configured to include the mass. One way to achieve this is to create a reaction force that progressively increases with distance from the equilibrium position or zone.

[0005] Figure 1A shows a simplified sketch, which illustrates a simple case of system 10 having a mass mass 12 held by a spring 14 that can operate in compression or extension when the mass mass 12 is moved away from an equilibrium position 16. Figure 1B is an example of a force response curve 18 associated with system 10 in Figure 1A.

[0006] When a mass 12 is driven to vibrate by a drive generator (not shown) operating at a given frequency, it vibrates at the drive frequency. However, the mass 12 in Figure 1A is a harmonic oscillator with a natural frequency W0. When the drive frequency is close to or coincides with the natural frequency, resonance behavior is observed, and this resonance behavior results in a significantly larger amplitude of vibration (and consequently, an amplitude of acceleration response). The frequency spectrum 20 of the acceleration response for a linear actuator having a linear force curve as shown in Figure 1B is presented in Figure 1C. The frequency spectrum 20 represents the level of acceleration (force in G) that will be shown for a mass 12 driven at a given drive amplitude for different drive frequencies. The resonance frequency W0 is directly linked to the slope k of the linear force response curve 18.

[0007] For example, in the case of a tactile actuator, it is typically required to maximize the acceleration response of the mass 12 within existing constraints. In the case of a linear force response curve 18 as shown in Figure 1B, the linear actuator can exhibit a frequency response spectrum 20 as shown in Figure 1C, which may be seen to be concentrated at a natural frequency W0, and it may be said that it has resonance at that natural frequency W0. When the mass 12 is driven at the frequency corresponding to the natural frequency W0, it will oscillate significantly and show a stronger change in acceleration due to resonance at that frequency, but when driven at other frequencies, it will oscillate much less and therefore tend to produce a smaller acceleration. The value of the natural frequency W0 is linked to the slope k of the force response curve 18. For example, in the case of a tactile actuator, it may be preferable, for example, that the frequency response be more versatile and not concentrated at a single resonant frequency. In one example, it may be desirable to use a single type of tactile actuator to operate with various electronic device models (each having a different driving frequency). A narrowband frequency response spectrum, such as the one shown in Figure 1C, may not satisfactorily meet this need, for example, requiring the spring constant to be adapted to the driving frequency of a particular device. Furthermore, a narrowband frequency response spectrum may not tolerate significantly different frequencies in tactile signals, for example.

[0008] Other areas where improvements may be sought include, for example, reducing production costs, improving scalability, acceleration response, or reliability, or simply providing a new type of force response curve or frequency response spectrum. [Means for solving the problem]

[0009] According to a first embodiment, a linear actuator is provided comprising a magnetized mass and at least one magnet configured to interact with the magnetized mass in contributing to defining a force response curve. The at least one magnet may be positioned transversely adjacent to the linear displacement path of the mass. In fact, the force response curve derived from a magnet positioned adjacent to the linear displacement path can be significantly different from the force response curve derived from a magnet positioned at the end of the linear displacement path, and this difference can be utilized in creating a new, advantageous force response curve in at least some applications. Alternatively, providing a magnet positioned adjacent to the linear displacement path can simply provide an advantageous alternative to positioning the magnet at the end of the linear displacement path, which can, for example, allow limiting the footprint length of the linear actuator in scenarios where a limited length is required. Alternatively, providing a magnet positioned adjacent to the linear displacement path can be used to provide a very strong return force when the magnetized portion of the mass is positioned adjacent to a magnet having the same magnetic orientation as the magnetized portion of the mass, or otherwise, to provide an alternative means of contributing to or defining the force response curve.

[0010] Accordingly, according to the first embodiment, a linear actuator is provided, the linear actuator comprising a mass mass movably mounted in a linear displacement path, the mass mass having a permanent magnetic field; a drive force generator configured to selectively impart acceleration to the mass mass along the path direction of the linear displacement path; and at least one magnet disposed adjacent to the linear displacement path transversely in such a manner as to interact with the magnetic field of the mass mass and thereby generate a magnetic force, wherein the amplitude of the magnetic force varies with respect to the position of the mass mass in the linear displacement path according to a force response curve.

[0011] According to a second embodiment, a linear actuator is provided having a reaction force path that defines a force response curve having a plateau or a relatively stable non-zero return force response between two relatively spaced inflection points, where each inflection point precedes a zone of significant increase in return force, one of which is associated with a zero force point or rest position. This can be achieved by using a sequence of elastic members for defining the reaction force path and a mass having two oppositely oriented magnetized portions.

[0012] Accordingly, according to a second embodiment, a linear actuator is provided, the linear actuator comprising a mass mass movably mounted in a linear displacement path, a drive force generator configured to selectively impart a driving force to the mass mass along the path direction of the linear displacement path, and a reaction path for generating a return force on the mass mass along the path direction of the linear displacement path, wherein the amplitude of the return force varies as a function of the position of the mass mass in the linear displacement path according to a force response curve, the force response curve having a region of increasing return force associated with the opposite end of the linear displacement path, one of which leads to a point of maximum return force, and a plateau region of non-zero return force located between the regions of increasing return force, the non-zero return force being between 5% and 30% of the maximum return force over a distance greater than the length of either region of increasing return force.

[0013] Accordingly, in another embodiment, a linear actuator is provided, the linear actuator comprising a mass mass movably mounted in a linear displacement path, a drive force generator configured to selectively impart a driving force to the mass mass along the path direction of the linear displacement path, and a reaction force path configured to impart a return force to the mass mass along the path direction of the linear displacement path, wherein the mass mass has a permanent magnetic field generated by first and second magnetized portions, the first and second magnetized portions being spaced longitudinally apart from each other and each having an individual magnetic field, the magnetic fields of the two magnetized portions being oriented longitudinally and directed opposite to each other, the reaction force path being defined by a combination of elements spaced longitudinally apart from each other with respect to the linear displacement path, the elements including A-type force elements being associated with a first end of the mass mass, and a sequence of B-type and A-type force elements being associated with a second end of the mass mass.

[0014] According to a third embodiment, a mode of operation for a linear actuator having a broad frequency response spectrum is provided by shifting the resonant frequency, which includes unbalancing the energy input on one side or the other. In fact, in this way, a single linear actuator can operate at significantly different frequencies and with significantly different amplitudes.

[0015] Accordingly, according to this third aspect, a method for operating a linear actuator is provided, the linear actuator comprising a mass mass movably mounted in a linear displacement path, a drive force generator configured to selectively impart acceleration to the mass mass along the path direction of the linear displacement path, and a reaction force path for generating a return force on the mass mass along the path direction of the linear displacement path, wherein the amplitude of the return force varies as a function of the position of the mass mass in the linear displacement path, the method comprising the steps of: oscillating the mass mass in the linear displacement path at a first frequency and a first acceleration amplitude, the drive force generator being operated with maximum force, the first acceleration amplitude corresponding to the maximum acceleration amplitude; and then oscillating the mass mass in the linear displacement path at a second frequency and a second acceleration amplitude, the second frequency being separated from the first frequency by at least 1 / 5, preferably 1 / 4, of the frequency value of the first frequency, and the second acceleration amplitude being at least 40%, preferably at least 50%, of the first acceleration amplitude.

[0016] In another embodiment, a linear actuator is provided, the linear actuator comprising: a mass mass movably mounted in a linear displacement path; a drive force generator configured to selectively impart acceleration to the mass mass along the path direction of the linear displacement path; and a reaction path that generates a return force on the mass mass along the path direction of the linear displacement path, wherein the amplitude of the return force varies as a function of the position of the mass mass in the linear displacement path, and further varies as a function of the vibration frequency of the mass mass according to a frequency response curve, the frequency response curve having a first frequency response peak and a second frequency response peak, the first frequency response peak being associated with the maximum frequency response of the vibration of the mass mass at the natural frequency of the reaction path, and the second frequency response peak being separated from the first frequency response peak by at least 1 / 5, preferably 1 / 4, of the frequency value of the first frequency response peak, and having an amplitude of at least 40%, preferably at least 50%, of the amplitude of the first frequency response peak.

[0017] In another embodiment, a linear actuator is provided, the linear actuator comprising a mass mass movably mounted in a linear displacement path, the mass mass having a magnetic segment, a drive force generator configured to selectively impart acceleration to the mass mass along the path direction of the linear displacement path, and a reaction force path that generates a return force when the mass mass is displaced from a rest position, the return force directed toward the rest position along the path direction of the linear displacement path, the amplitude of the return force varying as a function of the position of the mass mass in the linear displacement path according to a force response curve, and the reaction force path comprising a permanent magnet force element, the permanent magnet force element disposed adjacent to the linear displacement path transversely and magnetically coupled to the magnetic segment.

[0018] In another embodiment, a linear actuator is provided, comprising: a mass mass movably mounted in a linear displacement path; a drive force generator configured to selectively impart a driving force to the mass mass along the path direction of the linear displacement path; and a reaction force path that generates a return force when the mass mass is displaced from a rest position, wherein the return force is directed toward the rest position along the path direction of the linear displacement path, and the amplitude of the return force varies as a function of the position of the mass mass in the linear displacement path according to a force response curve, the force response curve having a region of increasing return force associated with the opposite end of the linear displacement path and a plateau region located between the region of increasing return force.

[0019] In another embodiment, a method is provided for operating a linear actuator comprising a mass mass movably mounted in a linear displacement path, the method comprising the steps of applying a driving force to the mass mass along the path direction of the linear displacement path to accelerate the mass mass along the linear path, the reaction path generating a return force when the mass mass is displaced from a rest position, the return force directed toward the rest position along the path direction of the linear displacement path, the amplitude of the return force varying as a function of the position of the mass mass in the linear displacement path according to a force response curve, the force response curve having a region of increasing return force associated with the opposite end of the linear displacement path and a plateau region located between the region of increasing return force.

[0020] In another embodiment, a linear actuator is provided, comprising: a mass movably mounted in a linear displacement path; a drive force generator configured to selectively impart acceleration to the mass along the path direction of the linear displacement path; and a reaction force path that generates a return force when the mass is displaced from a rest position, the return force directed toward the rest position along the path direction of the linear displacement path, the amplitude of the return force varying as a function of the position of the mass in the linear displacement path according to a force response curve, and the reaction force path being formed from a combination of at least two force elements, including an A-type force element and a B-type force element.

[0021] In another embodiment, a method is provided for operating a linear actuator comprising a mass mass movably mounted in a linear displacement path, the method comprising the steps of: applying a driving force to the mass mass along the path direction of the linear displacement path to accelerate the mass mass along the linear path; a reaction path generating a return force when the mass mass is displaced from a rest position, the return force directed toward the rest position along the path direction of the linear displacement path, the amplitude of the return force varying as a function of the position of the mass mass in the linear displacement path according to a force response curve; the reaction path is formed from a combination of force elements comprising a first A-type force element and a second A-type force element, the second A-type force element oriented opposite to the first A-type force element; the step of applying the driving force is performed in an iterative manner at a predetermined driving frequency and predetermined driving amplitude, the mass mass is caused to oscillate between opposite ends of the linear displacement path at a first frequency and a first acceleration amplitude in response to the driving force and the reaction path.

[0022] In another embodiment, a linear actuator is provided, comprising a mass mass movably mounted in a linear displacement path, a drive force generator configured to selectively apply a driving force to the mass mass along the path direction of the linear displacement path, and a reaction force path that generates a return force when the mass mass is displaced from a rest position, the return force directed toward the rest position along the path direction of the linear displacement path, the amplitude of the return force varying as a function of the position of the mass mass in the linear displacement path according to a force response curve, the force response curve being asymmetric with respect to the rest position, and when the drive force generator applies a driving force in an iterative manner in alternating directions at a predetermined drive frequency and a predetermined drive amplitude, the force response curve brings the mass mass to a dynamic equilibrium oscillation between opposite ends of the linear displacement path at a predetermined acceleration amplitude, the acceleration amplitude varying as a function of the drive frequency with respect to a constant drive amplitude according to a frequency response curve.

[0023] According to another aspect, there is provided a method of operating a linear actuator including a mass movably mounted within a linear displacement path, the method comprising applying a driving force to the mass along a path direction of the linear displacement path, thereby accelerating the mass along the linear path, wherein a reaction force path generates a return force when the mass is displaced from a rest position, the return force is directed toward the rest position along the path direction of the linear displacement path, the amplitude of the return force varies as a function of the position of the mass within the linear displacement path according to a force response curve, the force response curve is asymmetric with respect to the rest position, said step of applying includes applying the driving force in an alternating direction, at a predetermined driving frequency and with a predetermined driving amplitude, in a repetitive manner, thereby bringing the mass into dynamic equilibrium vibration between opposite ends of the linear displacement path, and the acceleration amplitude depends on the driving frequency for a given driving amplitude according to a frequency response curve.

[0024] Many further features and combinations thereof concerning the present improvement will appear to those skilled in the art following a reading of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] [Figure 1] It is a schematic simplified view of an exemplary linear actuator, a view showing the force response curve thereof, and a view showing the frequency response curve thereof. [Figure 2A] It is a schematic simplified view of an example of a force element that will be referred to herein as type A. [Figure 2B] It is a view showing the force response curve thereof. [Figure 2C] It is a view showing another example of a type A force element. [Figure 2D] It is a view showing another example of a type A force element. [Figure 2E] It is a schematic simplified cross-sectional view of a different example of a force element. [Figure 2F] It is a schematic simplified cross-sectional view of a different example of a force element. [Figure 2G]This is a schematic, simplified cross-sectional view of different examples of force elements. [Figure 3A] These are various graphs used to illustrate how a mass can be driven at different frequencies by creating an imbalance in the amount of energy supplied to it. [Figure 3B] These are various graphs used to illustrate how a mass can be driven at different frequencies by creating an imbalance in the amount of energy supplied to it. [Figure 3C] These are various graphs used to illustrate how a mass can be driven at different frequencies by creating an imbalance in the amount of energy supplied to it. [Figure 3D] These are various graphs used to illustrate how a mass can be driven at different frequencies by creating an imbalance in the amount of energy supplied to it. [Figure 3E] These are various graphs used to illustrate how a mass can be driven at different frequencies by creating an imbalance in the amount of energy supplied to it. [Figure 4A] This is a simplified schematic diagram of another example of a type A force element. [Figure 4B] This figure shows the force response curve. [Figure 5A] This is a schematic, simplified diagram of an example of a force element that will be referred to as type B in this specification. [Figure 5B] This figure shows the force response curve. [Figure 5C] This figure shows the frequency response curve. [Figure 5D] This figure presents another example of a Type B force element. [Figure 5E] This figure presents another example of a Type B force element. [Figure 5F] This figure presents another example of a Type B force element. [Figure 6A] This is a schematic diagram of another example of a force element. [Figure 6B] This figure shows the force response curve. [Figure 6C] The figure shows other examples. [Figure 6D] The figure shows other examples. [Figure 7A] This figure shows other examples of force elements. [Figure 7B] This figure shows the force response curves for each force. [Figure 8A] This figure shows other examples of force elements. [Figure 8B] This figure shows the force response curves for each force. [Figure 8C] This figure shows an exemplary mass with two magnetic segments. [Figure 9A] This diagram illustrates an example of a complex reaction force path. [Figure 9B] This figure shows the force response curves of each individual element. [Figure 9C] This figure shows the force response curves of each individual element. [Figure 9D] This figure shows the total force response curve for the system. [Figure 9E] This figure shows another example. [Figure 10A] This figure illustrates another example of a complex reaction path. [Figure 10B] This figure shows the force response curves of each individual element. [Figure 10C] This figure shows the force response curves of each individual element. [Figure 10D] This figure shows the total force response curve for the system. [Figure 10E] This figure shows the frequency response curve. [Figure 10F] The figure shows other examples. [Figure 10G] The figure shows other examples. [Figure 10H] The figure shows other examples. [Figure 10I] The figure shows other examples. [Figure 10J]The figure shows other examples. [Figure 10K] The figure shows other examples. [Figure 11A] This figure shows a modified example corresponding to the complex reaction force path in Figure 10A. [Figure 11B] This figure shows the frequency response curves for each of them. [Figure 12A] This figure shows a modified example corresponding to the complex reaction force path in Figure 10A. [Figure 12B] This figure shows the frequency response curves for each of them. [Figure 13A] This figure presents an alternative example of a complex reaction path. [Figure 13B] This figure presents an alternative example of a complex reaction path. [Figure 14A] This is a perspective view of an exemplary linear actuator capable of exhibiting a force response curve as shown in Figure 10D and a frequency response spectrum as shown in Figure 10E. [Figure 14B] This figure shows only the mass element. [Figure 15] This is a schematic diagram of an example computer. [Figure 16] This is a schematic diagram of an electronic device incorporating a computer and a linear actuator. [Figure 17A] This is a schematic diagram of different modifications of a linear actuator, in which different mechanisms are used to mobilize a mass within a linear displacement path. [Figure 17B] This is a schematic diagram of different modifications of a linear actuator, in which different mechanisms are used to mobilize a mass within a linear displacement path. [Figure 17C] This is a schematic diagram of different modifications of a linear actuator, in which different mechanisms are used to mobilize a mass within a linear displacement path. [Figure 17D]This is a schematic diagram of different modifications of a linear actuator, in which different mechanisms are used to mobilize a mass within a linear displacement path. [Modes for carrying out the invention]

[0026] Figure 1A shows a relatively simple example of a linear actuator 22 that may be used to provide haptic feedback. Using this example, some language useful for describing other linear actuators that will follow will be introduced. A linear actuator 22 can generally be said to include a mass 12 that can move linearly by reciprocating along a linear path 24. The linear path 24 may be defined by a linear guide, for example, by being constrained by a housing 26 (in which case the mass 12 may be slidably engaged) that defines a linear path 24 longer than the mass 12. Other exemplary ways of defining the linear path will be detailed below in relation to Figures 17B to 17D, which are discussed later.

[0027] Furthermore, the linear actuator 22 includes some form of drive force generator (not shown) configured to selectively apply (or not apply) a drive force to the mass 12, thereby facilitating its movement along the linear path 24. In the case where the mass 12 has one or more magnetic segments, the drive force generator may be, for example, an electromagnet magnetically coupled to the permanent magnetic field of the mass 12, but in other embodiments, other forms of drive force generators or methods for driving the movement of the mass may be preferred.

[0028] The linear actuator 22 is further provided with a reaction path, which in the example shown in Figures 1A to 1C is provided entirely by a compression spring 14, which is fixed between the mass 12 and the housing 26 at one end 28. In this embodiment, the compression spring 14 has a spring constant k, which can remain constant along the entire span of displacement along the linear path 24, thus generating a linear force response curve 18 (Figure 1B). The force response curve 18 of the reaction path 32 (represented here by a dashed box in Figure 1A) is shown in Figure 1B. As shown on the left side of the rest position 16 in Figure 1B, the reaction path 32 generates a gradually (linearly) increasing return force 30. The further the mass is moved to the left along the linear path from the rest position 16, the more the spring 14 is stretched, according to the typical mass / spring behavior governed by the equation F = kx (where x is the displacement). As shown to the right of the rest position 16 in Figure 1B, the reaction force path 32 provides a return force 30 that gradually increases as the mass is moved further to the right from the rest position 16 (compressing the spring 14).

[0029] In this case, the force response curve 18 is linear in the sense that it has a constant slope k, and the force response is proportional to the distance from the rest position 16. Since the maximum range of the linear displacement path 34 and the amplitude of the maximum displacement 34 may vary from embodiment to embodiment, it may be practical to provide a value for the slope k in relative units. In fact, regardless of the embodiment, the linear displacement path 24 may have a static rest position 16 (also known as the equilibrium position), and the mass mass 12 may be moved from the static rest position 16 in two directions to the corresponding ends 28, 36 of the linear displacement path 24 by the drive force generator. The ends 28, 36 of the linear displacement path 24 may be defined by a reaction force path, for example, the boundary may even be defined by a hard stop, or by characteristics such as the maximum force and frequency of the drive force generator and friction, which can be translated, for example, to the maximum range of displacement at perfect resonance. Therefore, the maximum force 38 and the maximum range / span of displacement 34 are characteristics of a given linear actuator, regardless of the details of the implementation. To define normalized units, we define a unit in which half of the entire span of the linear displacement path 24 is equal to the maximum return force 38. For example, half of the maximum range of displacement 34 can have a value of 1 in the units of maximum displacement, and the maximum return force 38 acting by the reaction path can have a value of 1 in the units of maximum return force 38. Thus, the slope can be expressed in units of increasing force per increasing unit of increasing displacement. In the context of the linear reaction path, using the definition presented above, the slope remains always equal to 1 in these units on either side of the rest position 16 along the entire displacement range. The slope is also 1 at the rest position 16, clearly defining the static rest position 16. Furthermore, the force response curve 18 is symmetrical and provides an equal return force 30 regardless of the mass mass position orientation relative to the equilibrium position 16.

[0030] Therefore, the shape of the force response curve 18 is also a characteristic of the linear actuator and is defined by the force elements in the reaction force path. In this embodiment, there is a single force element (compression spring 14) that defines the force response curve 18 as a whole, but it is understood that other embodiments may be used without departing from the presented disclosure. Examples of other embodiments are presented below.

[0031] The shape of the force response curve 18 will be accompanied by dynamic effects that can be visualized during motion. In this example, for example, the force response curve 18 includes a first region 40 of increasing return force 30 extending from the rest position 16 to the first end 28 of the linear displacement path 24 on the first side of the rest position 16, and a second region 42 of increasing return force 30 extending from the equilibrium position 16 to the second end 36 of the linear displacement path 24 on the second side of the equilibrium position 16. The two regions 40, 42 of increasing return force 30 define the entire force response curve 18. The return force 30 always acts on the orientation of the displacement, which may be due to the fact that the linear displacement path 24 constrains movement along its path direction, but acts in the opposite direction depending on the side relative to the rest position 16, and therefore always acts in a manner that returns the mass 12 to the rest position 16 (hence the expression "return" force).

[0032] When the mass mass 12 is moved to one side against the return bias of the spring 14 and suddenly released from the external force, the spring 14 will pull the mass mass 12 back beyond the rest position 16, and the mass mass 12 will oscillate back and forth around the rest position 16 for a certain amount of time before its energy is dissipated in friction and before the mass mass 12 settles back to the “static” rest position 16 (which can be a region instead of a point in a nonlinear system, but a point is typically preferred with respect to touch). The frequency at which the mass mass 12 oscillates back and forth is the natural frequency of the linear actuator and will be denoted as W0. W0 depends on the slope of the force response curve 18, which in this embodiment is directly related to the spring constant k. If the drive force generator is configured to repeatedly supply drive energy into the system 10 at a frequency near the natural frequency W0 (which can be done, for example, by operating a coil with an alternating current), the repeatedly added energy will result in a "resonance" where the moving mass 12 reaches increasingly large amplitudes of displacement and acceleration until it satisfies dynamic equilibrium oscillation, in which energy loss due to friction corresponds to the amount of energy introduced into the system in each cycle. Electromagnets (coils) are not the primary focus of this application, and for clarity, electromagnet coils have been omitted from various drawings discussed in this disclosure. However, electromagnets C (more specifically, electromagnet coils) are shown in at least the embodiments of Figures 5F, 10A, 10F to 10J, 11A, 12A, 14A, and 17A to 17D.

[0033] The expression "repeatedly supplying driving energy into the system at frequencies near the natural frequency" can be best understood by referring to Figure 1C. Figure 1C presents a graph showing the force (acceleration) response spectrum 20 of the linear actuator 22 in Figure 1A as a function of the driving frequency with respect to a given driving energy amplitude. In fact, if the same amount of energy is supplied to the mass 12, but at a frequency different from W0, the mass 12 will still be driven, but some of the energy will not be efficiently transferred into motion. This is because the movement of the spring 14 does not resonate with the drive, and therefore the amplitude of the acceleration and displacement of the mass 12 driven by the driving force becomes smaller. In fact, the peak shown in the frequency response graph corresponds to frequency W0. It can be seen that as the driving frequency is shifted further away from the natural frequency W0, the resulting force response gradually decreases.

[0034] In a context where a drive force generator has the maximum drive force generator value (maximum amount of drive energy) (which, in the case of an electromagnet (coil) drive, can, for example, correspond to the maximum voltage), the maximum drive force generator can be correctly timed so that its maximum voltage input oscillates between positive and negative at its natural frequency W0. 、 This will only produce the maximum acceleration response value Gmax, and the value of the maximum driving force generator will produce a smaller acceleration response the further it is operated from its natural frequency W0, and in this example, a 1 / 5 shift from W0 with respect to frequency will produce only a negligible acceleration response (probably less than 5% of the maximum acceleration response value).

[0035] Here again, the frequency response spectrum 20 is defined by the force response curve 18, which is defined by the force elements that define the reaction force paths. Thus, just as the force response curve 18 can be a characteristic of the linear actuator 22, or the details of the force elements can be a characteristic of the linear actuator 22, the frequency response spectrum 20 of the linear actuator 22 can be said to be a characteristic of the linear actuator 22.

[0036] Haptic actuators can be used in electronic devices such as smartphones and remote controllers. Haptic actuator manufacturers may specialize in manufacturing haptic actuators and may sell their haptic actuators to different electronic device manufacturers. Haptic actuator manufacturers may want a single model of haptic actuator (which is industrially produced in a manner that reduces production costs) to be easily adaptable to different situations (e.g., drive frequencies which may vary from one electronic device manufacturer to another, or even between uses of a single electronic device (e.g., different drive frequencies are intended to produce different vibration frequencies perceptible to the user)). It is easy to see that a linear actuator 22, such as the one presented in Figure 1A, may not be well adapted to meet such needs, given the fact that its acceleration response spectrum 20 is strongly concentrated around its own value. Thus, there may be a demand for a linear actuator with a broader frequency response spectrum, or simply a demand for a linear actuator better adapted to provide the user with more complex haptic signals (e.g., vibrations across a specific band of frequency). From a user's perspective, this might be perceived as a range of slower or faster vibrations (frequency), as opposed to, for example, only stronger or weaker vibrations (amplitude).

[0037] The following description examines several alternative force elements, their potential effects on the force response curve, and their potential effects on the frequency response curve. It was found that some force elements (and their combinations) were better fitted, for example, to provide a more satisfactoryly broadband frequency response spectrum.

[0038] Figure 2A presents an exemplary embodiment of a first type of force element 100. Figure 2B presents its force response curve 118 as shown in Figure 2A. In the exemplary embodiment of Figure 2A, the force element 100 has a permanent magnetic field 102 connected to the magnetic field of a mass 104. However, it should be noted that in alternative embodiments, an equivalent force response curve 118 may be implemented by a spring element 114 as schematically shown in Figure 2C. Thus, the force response curve 118 may be a more important characteristic defining the type of force element than the details of its fabrication or the nature of its interaction with the mass 112. Therefore, in order to define this first type of force element (which will hereafter be referred to as the “Type A” force element), we will focus on the characteristic features of the force response curve 118 in Figure 2B, in contrast to other characteristics.

[0039] As shown in Figure 2B, force element type A provides a region of increasing return force 140 on the first side of the rest position 116, and a plateau region 142 of relatively low, non-zero return force on the second side of the rest position 116. In fact, when the mass 112 is moved to the left of the rest position 116, the mass 112 will perceive a strongly increasing repulsive force, which will act to return the mass 112 towards the rest position 116 (i.e., the point where the force response line intersects the zero force axis on the graph in Figure 2B). However, when moved to the right of the rest position 116, the return force will increase slightly and quickly reach a plateau of relatively constant return force. The point of maximum return force can be associated with the end 136 of the linear displacement path 124 on the left side of the rest position 116. As presented above, the value of the maximum return force can be defined by several characteristics of the linear actuator (e.g., the maximum force of the drive force generator, the frequency of the drive force generator, the amount of friction, and the shape of the force response curve 118). The maximum return force at the end 136 of the first side (i.e., the region of increasing return force 140) can be significantly high (e.g., more than twice, three times, five times, and even eight times the level of force reached in the plateau region 142). The plateau region 142 can extend to a linear displacement distance at least equal to or at least 1.5 times the linear displacement distance extending to the region of increasing return force 140.

[0040] Since the values ​​of the maximum return force and the maximum range of displacement can vary independently of each other depending on the embodiment and the unit used, it may be useful to define normalized units for the purpose of defining the slope of the change in return force with respect to the change in displacement. In normalized units, the value of the maximum return force may be set to be equal to half the distance span of the linear displacement path 124. For example, the maximum return force of a linear actuator may be set to have a unit value of 1 return force unit, and half the total span of the linear displacement path 124 may be set to have a value of 1 displacement unit. Using this definition, it may be seen that the region of increasing return force 140 on the left side of the rest position 116 has a slope where it remains above 1 over more than 3 / 4 of its span (and even over the entire span), while the plateau region 142 may have a slope where it remains between zero and 1 (and even below 0.5) over more than 3 / 4 of its span (or even over the entire span). Furthermore, the return force in the plateau region 142 can be between 5% and 20% of the maximum return force over more than three-quarters of its span. This plateau region 142 is an interesting feature from the perspective of movement dynamics.

[0041] The shape of the force response curve 118 defined by such a type A force element 100 is given by equation y=b x This is somewhat reminiscent of the exponential function formed by -1. Therefore, the type A force element is given by equation y=b x It can be said that the response curve 118 is shaped as a part of a curve formed by an exponential function formed by -1, where the position x=0 corresponds to the rest position 116 of the force response curve 118 (where the return force is zero).

[0042] In a particular embodiment illustrated in Figure 2A, the force element 100 has a permanent magnet force element 106, which is arranged transversely adjacent to the linear displacement path 124. The permanent magnet force element 106 is configured to generate a magnetic field 102, which is parallel to and in the same direction as the magnetic field 104 of one or more magnetic segments of the mass mass 112 to which it is connected. In the illustrated embodiment, the permanent magnet force element 106 generates a magnetic field 102 on at least two transverse sides 108 of the mass mass 112 in a manner that balances the force which is closely aligned with the orientation of the movement. For example, the permanent magnet force element 106 may consist of a single annular magnet 107 surrounding the mass mass 112, as schematically shown in Figure 2E, or it may consist of a plurality of magnets 111 distributed symmetrically around the mass mass 112 to balance, as shown in Figures 2F and 2G. The embodiment in Figure 2A uses a permanently magnetized force element 106, but alternative embodiments may use an electromagnet 110, or a combination of a permanent magnet and an electromagnet, as shown in the example in Figure 2D. The magnetized force element 106 is positioned adjacent to the linear displacement path 124 of the mass mass 112, allowing the mass mass 112 to move alongside it.

[0043] Figure 2A shows a mass mass 112 (or, more specifically, its magnetic segment / magnetized portion) in rest position 116 relative to force element 100. When in rest position 116 relative to type A permanent magnet force element 106, the magnetic segment 114 of the mass mass 112 may be seen to be longitudinally adjacent to one or more magnets forming the force element 106. More specifically, in rest position 116, the longitudinal end of the magnetic segment 114 of the mass mass 112 may be transversely aligned with (or very close to transversely aligned with) the opposite longitudinal end 146 of the permanent magnet force element 106. The magnetized segment 114 of the mass mass is magnetized in the same orientation and direction as at least one magnet forming the drive force generator. The force response curve 118 is roughly reminiscent of the force response curve of the spring element 114 shown in Figure 2C, and in some embodiments, the spring-type element shown in Figure 2C may be used as an alternative to the magnetic-type force element 106 in Figure 2A. Similarly, the magnetic force element 106 in Figure 2A may be considered an alternative to the spring element 114 shown in Figure 2C, and in some embodiments, the magnetic force element 106 may have advantages over the spring element 114 in Figure 2C. In fact, for example, the magnetic force element 106 may be less prone to wear than the spring element 114. Similarly, if the linear actuator 122 is used, for example, in relation to touch, it may be required to fit within a limited footprint in an electronic device. The footprint may have a predetermined length specification, which may be difficult to address with the spring element 114 positioned at one end of the displacement path and may be easier to address with the magnetic force element 106 positioned adjacent to the displacement path, for example.

[0044] Figure 2D presents an alternative embodiment to the embodiment in Figure 2A, which uses a combination of a permanent magnet and an electromagnet 110 within the force element 106 instead of using a permanent magnet alone. When the electromagnet 110 is activated, the force response curve can be the same as or equivalent to the force response curve 118 presented in Figure 2B, for example, while when the electromagnet 110 is deactivated, the force response curve may remain similar in shape but with a reduced amplitude.

[0045] For the purposes of this specification, the elastic force response path elements shown in Figures 2A, 2C, and 2D can be considered to be of "Type A".

[0046] In the embodiment shown in Figure 2A, the permanent magnetic force element 106 has a permanent magnetic field 102 oriented parallel to the linear displacement path 124, and at the rest position 116, the permanent magnetic force element 106 is linearly positioned adjacent to the magnetic segment 144 of the mass mass 112, and the permanent magnetic field 102 is oriented parallel to and in the same direction as the permanent magnetic field of the magnetic segment 144.

[0047] It should be noted that the force response curve 118 of the Type A element is asymmetrical in the sense that it differs significantly depending on the side along which the mass 112 is moved, and that it has a slope that changes along its length. Here, a linear displacement path 124 corresponds along its length, and the slope changes based on the position x along this linear displacement path 124. Since the slope changes along its length, its resonant frequency can be shifted to some extent from the natural frequency W0 by unbalancing the amount of driving energy in a way that artificially shifts the dynamic center of movement toward one side or the other. This is schematically shown in Figure 3A, where different resonant frequencies are represented by slopes W0, W1, and W2.

[0048] Figure 3B presents one method for driving the movement of mass 112 by alternating current in a balanced manner. A rectangular wave 148 is shown as one possible method for maximizing the amount of energy, although other wave shapes may be used alternatively. The energy is balanced in the sense that the amount of energy provided to drive the mass 112 to the right is roughly equal to the amount of energy provided to drive the mass 112 to the left. This is shown as an example in Figure 3B, where the voltage amplitude on the positive side of the graph is equal to the voltage amplitude on the negative side of the graph. This can result in reaching the maximum acceleration amplitude by driving the mass 112 at the natural frequency W0 shown in Figure 3A. Figures 3C and 3D present methods for unbalancing the amount of energy to one side or the other. Here, the unbalance is achieved by adding a DC bias to the signal. In Figure 3C, the DC bias 152 is positive, which shifts the dynamic center of movement 150 to the left and shifts the peak resonant frequency from W0 to a higher frequency W1. In Figure 3D, the DC bias 154 is negative, which shifts the dynamic center of motion 156 to the right, shifting the peak resonant frequency from W0 to a lower frequency W2. Figure 3E is an example of another method of shifting the peak resonant frequency toward W2. In Figure 3E, instead of adding a DC bias, the wave shape is altered such that the amount of time A during which the electromagnet is driven by a positive signal is shorter than the amount of time B during which the electromagnet is driven by a negative signal. In both the example in Figure 3E and the example in Figure 3D, there is a regulated imbalance between the amount of energy transferred to the mass 112 in one orientation and that for the other orientation.

[0049] Even if a Type A element presents a plateau region 142 extending over a given length of the linear displacement path 124, and even if the amount of acceleration (more precisely, deceleration in this case) caused by the element corresponds to the integral of the force response curve 118 over the said length, it will be understood that the use of a Type A element may be limited in itself, given that it lacks a more pronounced "dip" (referred to herein as an increase) of the return force on the right-hand side of the rest position 116, and may only be suitable for relatively small displacements, which may not be ideal for embodiments where a strong acceleration response is required. Indeed, in embodiments such as that presented in Figure 3A, the mass mass may tend to exceed the intended maximum amount of displacement on the right-hand side of the rest position 116.

[0050] Figure 4A presents another example of a Type A force element 100. In this example, the force element 100 is formed from a permanent magnet and can therefore be referred to as a permanent magnet force element 106. The permanent magnet force element 106 consists of two sub-elements (magnetic elements 158), the magnetic elements 158 generating magnetic field lines parallel 159 to the magnetic field of the mass mass 104, in the same orientation, and offset therefrom (it can be abbreviated as a magnetic segment 144 oriented parallel, offset, and in the same orientation as the mass mass 112), as in the first Type A presented above. The magnetic element 158 ​​is immediately followed by a subsequent magnetic element 160, the magnetic element 160 generating magnetic field lines oriented perpendicular 162 to the linear displacement path 124, offset therefrom, and oriented toward it. The magnet element 160, oriented perpendicular to the linear displacement path 124 (or otherwise inward in the transverse direction), is positioned between the first magnet element 158 ​​and the rest position 116. This configuration may be referred to as a Half-Halbach arrangement, and as can be seen from the force response curve 164 presented in Figure 4B, the presence of the magnet element 160 oriented perpendicular to the linear displacement path 124 can be seen to increase the leftward slope of the force response curve 164 at the rest position 116. Increasing the leftward slope of the force response curve 164 at the rest position 116 may be desirable in some embodiments. Here, the terms “left side” and “right side” are used for simplification, but it should be noted that these references are merely used to refer to the orientation in which the design is presented in the drawings, and it should be understood that when viewing the device from the opposite orientation, the left and right sides of the drawings may be reversed. It should be noted that the slope of the force response curve 164 on the left side of the rest position 116 may be more pronounced in the context of the addition of the magnetic element 160 oriented transversely inward as shown in Figures 4A and 4B, compared to the embodiments shown in Figures 2A and 2B, which leads to a higher natural frequency W0.

[0051] Figure 5A presents yet another example of the force element 200. Figure 5B presents its force response curve 218. In the exemplary embodiment of Figure 5A, the force element 200 has a permanent magnetic field 202 connected to the magnetic field of the mass 204. However, it should be noted that in alternative embodiments, an equivalent force response curve 218 may be implemented by a spring element, such as the exemplary spring element 214 schematically shown in Figure 5D. One definitive feature of the force elements 200 in Figures 5A and 5D is their property of exhibiting an increasing force slope in a nonlinear exponential manner as the displacement increases. The force response curve 218 may be a key characteristic defining the type of force element 200, rather than the details of its fabrication or the nature of its interaction with the mass 212. Here, the force response curve 218 is of type y = -(x 3 This is somewhat reminiscent of the central part of the cubic polynomial function (i.e., the part concentrated around x=0), where the value of x=0 corresponds to the rest position. This second type of force element 200 will henceforth be referred to as the "Type B" force element.

[0052] More specifically, the point of maximum return force may be associated with the corresponding opposite ends 228, 236 of the linear displacement path 224. The force response curve 218 may be symmetrical, and the return force values ​​at the point of maximum return force 230 may be equal in magnitude but opposite in direction. As presented above, the value of the maximum return force may be defined by several characteristics of the linear actuator (e.g., the maximum or current operating force of the drive force generator, the frequency of the drive force generator, the amount of friction, and the shape of the force response curve 218). The force element may provide a region of increasing return force on the first side 240 of the rest position 216, a symmetrical region of increasing return force on the second side 241 of the rest position 216, and a plateau region 242 between them.

[0053] The plateau region 242 can extend to a linear displacement distance of at least half (or even equivalent to) the linear displacement distance extending to the increasing return force regions 240 and 241. The slope can be defined as defined above in units where the maximum return force of the linear actuator is equal to a value of 1, and half of the total span of the linear displacement path is equal to a value of 1. Using this definition, the increasing return force region 241 on the left side of the rest position 216 can be seen to have a slope that remains above 1 for more than 3 / 4 of its span (here, even over its entire span), while the plateau region 242 can have a slope that remains between zero and 1 for more than 3 / 4 of its span (here, even over its entire span). Furthermore, the return force in the plateau region 242 can remain below 10% of the maximum return force for more than 3 / 4 of its span (here, over its entire span). In this embodiment, since the plateau region 242 crosses the rest position 216, the slope of the force response curve is somewhat lower at the rest position 216. This plateau region 242 can be an interesting feature from the perspective of motion dynamics.

[0054] In a particular embodiment shown in Figure 5A, similar to the force elements in Figures 4A and 2A, the force element 200 is embodied with a permanent magnetic field 202, which is configured to interact with the magnetic field of the mass 204 in contributing to defining the reaction force path. The force element 200 has at least one magnet 111, which can be a permanent magnet, an electromagnet, or a combination of a permanent magnet and an electromagnet, which has a magnetic field 202, which is generally antiparallel to the magnetic field of the mass 204 (parallel but oriented in opposite directions) and is transversely offset from the magnetic field of the mass 204. More specifically, it can be positioned adjacent to the linear displacement path 224 of the mass 212, so that the mass 212 can move near the magnet 111. In one embodiment, the combined magnets 111 may be used on the opposite side of the linear displacement path 212, or on the corresponding opposite lateral side of the mass mass 212, and are arranged circumferentially apart from each other, as previously schematically shown in Figures 2E to 2G in relation to the embodiment shown in Figure 2A, or are circumscribing the linear displacement path 224, and are designed to balance and create forces resulting from a better alignment with the linear displacement path 224, for example, to avoid forcing the mass mass 212 into a transverse orientation.

[0055] Figure 5A shows a mass 212 (or more specifically, its magnetized segment 244) in equilibrium with respect to the force element 200. It should be noted that such a Type B magnetic force element can be transversely aligned with the magnetized segment 244 of the mass 212 at the rest position 216. In other words, while the Type A magnetic force element 106 was longitudinally adjacent to or offset from the magnetic segment 144 of the mass 112 to which it was magnetically connected (and therefore not transversely aligned) when at the rest position 116, the longitudinal position of the Type B magnetic force element 206 corresponds to (for example, overlaps with at least a portion of) the magnetic segment 244 of the mass 212 to which it was magnetically connected when at the rest position 216. Thus, it can be said that the magnetic force element 206 and the magnetic segment 244 are transversely aligned at the rest position 216. As shown in the force response curve 218 presented in Figure 5B, when the mass mass 212 is moved to a position to the left of the rest position 216, adjacent to the magnetic element 206, the mass mass 212 will first perceive a weak, slowly increasing repulsive force, and then a stronger, rapidly increasing repulsive force that acts to return the mass mass 212 towards the rest position 216. In this case, the force response curve 218 is symmetrical, and the force response is the same in both directions of the linear displacement path 224. The force response curve 218 is roughly reminiscent of the force response curve caused by progressively changing the force spring element 214 as shown in Figure 5D, which shows a spring constant k that increases over the displacement from the rest position 216, and in some embodiments, the spring element 214 as shown in Figure 5D can be used satisfactorily as an alternative to the magnetic element 206 in Figure 5A. Similarly, the magnetic force element 206 in Figure 5A can be considered an alternative to the spring element 214 shown in Figure 5D, and in some embodiments, the magnetic force element 206 may have advantages over the spring element 214 in Figure 5D.In fact, for example, the magnetic element 206 may be less prone to wear than the spring element 214. Similarly, when a linear actuator is used, for example, in relation to touch, it may be required to fit within a limited footprint in an electronic device. The footprint may have a predetermined length specification, which may be difficult to address with a spring positioned at one end of the displacement path and may be easier to address with a magnet positioned adjacent to the displacement path, for example.

[0056] Figure 5E presents an alternative embodiment to the embodiment shown in Figure 5A, which uses a combination of a permanent magnet and an electromagnet 210 within the magnetic element 206, instead of using a permanent magnet alone. When the electromagnet 210 is activated, the force response curve can be the same as or equivalent to the force response curve 218 presented in Figure 5B, for example.

[0057] For the purposes of this specification, force elements such as those shown in Figures 5A, 5D, and 5E may be referred to as "Type B".

[0058] Figure 5F presents yet another exemplary embodiment in which a B-type force element consists of individual B-type sub-elements that cooperate in generating a B-type force response curve. In fact, a B-type spring element 214 is combined with a B-type permanent magnet element 111, where the individual B-type force response curves of both elements are combined in the resulting composite B-type force response curve, which can be the same as (or equivalent to) the force response curve 218 presented in Figure 5B, for example.

[0059] A linear actuator having a type B force response curve (i.e., one like the one illustrated in Figure 5B) can have a frequency response spectrum 220 as shown in Figure 5C. Such a frequency response curve 220 can have several distinctive features. Firstly, it can have a broader bandwidth response spectrum than the frequency response of a linear actuator having a linear force response curve, for example, as shown in Figures 1B and 1C. In a broader bandwidth response, with respect to a given driving force amplitude, the acceleration (force G) amplitude of the mass 212 is reduced less with respect to a given difference in frequency from the peak frequency 266 than in a narrower bandwidth response spectrum. Moreover, in contrast to a single acceleration amplitude peak at a single frequency, it is possible for more than one acceleration amplitude peak or "bump" to exist in the frequency response spectrum 220. It is understood that frequency and acceleration amplitude peaks are taken when the mass is driven to dynamic equilibrium oscillation between opposite ends of the linear displacement path of the linear actuator. Finally, in the shape of the resonance curve of the frequency response spectrum, linear effects such as the foldover effect 268 may exist. In the foldover effect 268, for the same driving force amplitude and frequency, it is possible for more than one resonance energy (or dynamic equilibrium oscillation state) to exist at a given frequency, such as frequency V identified in Figure 5C.

[0060] Various methods exist that can utilize the foldover effect 268 arising from the nonlinearity present in the frequency response spectrum 220 of the linear actuator, and these can include actively selecting which resonant energy is used for a given driving force amplitude and frequency. For example, in one embodiment, it may be preferred to provide a flatter and more neutral response by selecting a lower power state, or to provide a higher gravitational acceleration (G-force) output by selecting a higher power state. This selection can be made in two different ways. In the first example, applying a first driving force amplitude at a first frequency can lead to exciting a first lower power state. If the first lower power state is desired, the driving force amplitude and frequency can then remain constant. Two different exemplary methods that can allow reaching a second higher power state (if desired) are presented here. First, the driving force can be excited at the same first frequency V, but at a higher driving force amplitude. This can excite a higher power state. Next, when a higher power state is reached, the driving force amplitude may be reduced back to the first driving force amplitude, which may be sufficient to sustain the higher power state, but may not be sufficient to excite it. Secondly, the driving force may be excited at a second frequency different from the first frequency, and at a position along the frequency response spectrum 220 where the foldover effect 268 is not present, but adjacent to and connected to the foldover region. In this embodiment, the foldover region extends to the right, and therefore the second frequency can be to the left of the foldover region. For example, in Figure 5C, frequency W is different from frequency V and is located along the frequency response spectrum 220 where the foldover effect 268 is not present, but is still adjacent to the region containing the foldover effect 268. Since there is no foldover at frequency W, a single high power state is excited.Next, the frequency is progressively changed from W towards the foldover region, which can lead to the sustaining of higher power states within the foldover region, for example, at frequency V. This is regardless of the fact that if the frequency had not been "folded over," this higher power state would not have been excited.

[0061] Figure 6A presents another example of the force element 300. In this example, the force element 300 consists of two sub-elements (a magnetic element 311 and a corresponding magnetic element 358 integrated within a mass 312), where the magnetic element 311 is oriented perpendicular to the magnetic field of the mass 312, directed transversely inward, and offset therefrom, and provided as part of the force element outside the linear displacement path 324. The corresponding magnetic element 358 integrated within the mass 312 is oriented perpendicular to the linear displacement path 324, directed transversely inward with respect to the linear displacement path 324, oriented in the same orientation as the magnetic element 311 outside the linear displacement path 324, and positioned adjacent to the longitudinally magnetized segment 344 of the mass 312. This configuration makes it possible to produce a force response curve 318 as shown in Figure 6B. The force response curve 318 is roughly reminiscent of the force response curve caused by a double opposing spring element 314 as shown in Figure 6C, and in some embodiments, the spring element 314 as shown in Figure 6C may be used as an alternative to the magnetic force element 306 in Figure 6A. Similarly, the magnetic force element 306 in Figure 6A may be considered an alternative to the spring element 314 as shown in Figure 6C, and in some embodiments, the magnetic force element 306 may have advantages over the spring element 314 in Figure 6C. In fact, for example, the magnetic force element 306 may be less prone to wear than the spring element 314. Similarly, when a linear actuator is used, for example, in relation to touch, it may be required to fit within a limited footprint in an electronic device. The footprint may have a predetermined length specification, which may be difficult to address with a spring positioned at one end of the displacement path and may be easier to address with a magnet positioned adjacent to the displacement path, for example.This force response curve 318 does not show a plateau region and provides a slope greater than 1 across the rest position, following the same unified definition provided in previous embodiments.

[0062] Figure 6D presents an alternative embodiment to the embodiment shown in Figure 6A, which uses a combination of a permanent magnet and an electromagnet 310 within the magnetic force element 306, instead of using a permanent magnet alone. When the electromagnet 310 is activated, the force response curve can be the same as or equivalent to the force response curve 318 shown in Figure 6B, for example.

[0063] For the purposes of this specification, force elements such as those shown in Figures 6A, 6C, and 6D may be referred to as "C-type" or as generating a C-type force response curve. The C-type force response curve is a function

number

[0064] Figure 7A presents another example of the force element 400, which incorporates several elements of the configuration shown in Figure 4A, but adds another magnetic element 458 after the magnetic element 160 which is oriented perpendicular to the linear displacement path 424. The other magnetic element 458 is oriented antiparallel to the magnetic field of the mass mass 412 and antiparallel to the magnetic field of the first magnetic element 158. This configuration is capable of producing a force response curve 418, as shown in Figure 7B, which can be roughly reminiscent of the force response curve 18, as shown in Figure 1B. In some embodiments, a spring element, as shown in Figure 1A, can be used as an alternative to the magnetic force element 406 in Figure 7A. Similarly, the magnetic force element 406 in Figure 7A can be considered an alternative to the spring element, as shown in Figure 1A, and in some embodiments, the magnetic force element 406 can have advantages over the spring element in Figure 1A. In fact, for example, the magnetic force element 406 may be less prone to wear than a spring. Similarly, when a linear actuator is used, for example, in relation to tactile sensation, it may be required to fit within a limited footprint in an electronic device. The footprint may have a predetermined length specification, which may be difficult to address with a spring positioned at one end of the linear displacement path and may be easier to address with a magnet positioned adjacent to the linear displacement path, for example.

[0065] Figure 8A presents another example of the force element 500. Figure 8A is similar to Figure 7A, but with the additional integration of an obliquely oriented magnetic element 558 adjacent to the magnetic segment 544 in the moving mass 512. The obliquely oriented magnetic element 558 influences the magnetic field lines, creating a curve in the right-hand portion 560 relative to the rest position 516 of the force response curve 518, as shown in Figure 8B.

[0066] The different force elements introduced above can be combined at different longitudinal positions along the linear displacement path, creating additional varying effects on the mass and allowing the force response curve to be adjusted according to the needs of a particular embodiment. Similarly, the mass can have more than one magnetized segment, and if more than one magnetized segment is present, it can be magnetized in different orientations.

[0067] In fact, referring to Figure 8C for example, an example of a mass mass 612 has two magnetic segments 644a and 644b, which are oriented antiparallel to each other and separated longitudinally from each other by a ferromagnetic spacer 660 (e.g., a soft ferromagnetic material). As illustrated in Figure 8C, the presence of the magnetic field 662b of the second magnetic segment 644b can compress the magnetic field 662a of the first magnetic segment 644a and increase their curvature, and the ferromagnetic spacer 660 further facilitates this, which can lead to a stronger concentration of magnetic field strength and greater coupling with other magnetic elements. For example, if the driving force generator is an electromagnet surrounding the mass mass 612 when the mass mass 612 is in its rest position, and the electromagnet is aligned transversely in such a manner that it overlaps longitudinally with the ferromagnetic spacer 660, the driving force generator can be significantly more efficient in imparting acceleration to the mass mass 612 for a given amount of energy than if the driving force generator were aligned with the mass mass 612 in any other way, or as if the second magnetic segment 644b were not present. Furthermore, tighter wound magnetic field lines can interact more efficiently with force elements arranged transversely adjacent to either (or both) of the magnetic segments 644a and 644b.

[0068] A first example of a composite reaction path composed of combinations of individual elements is shown in Figure 9A. In this example, two A-type elements 762a and 762b with opposite orientations are used, one on each side of the magnetized portion 744 of the mass block 712. Specifically, the force response curve 718a caused by the first element 762a is shown in Figure 9B, and specifically the force response curve 718b caused by the second element 762b is shown in Figure 9C. The force response curve 718b of the second element 762b can be seen as the inverse of the force response curve 718a of the first element 762a, since its orientation is opposite. Their effects are added together to produce the resulting composite force response curve 718c, shown in Figure 9D. Although Type A elements are used, it should be noted that the general shape of the resulting force response curve 718c is somewhat similar to the force response curve 218 associated with Type B elements, as presented in Figure 5B, and therefore can be considered a Type B force response curve. Combinations of one or more types of force path elements can be alternative methods for achieving a desired frequency response spectrum and may be advantageous in at least some embodiments. An exemplary embodiment presented in Figure 9E is capable of providing a force response curve similar to that achieved by the example presented in Figure 9A, but this can be achieved by using two oppositely oriented Type A spring elements 714 instead of two oppositely oriented Type A magnetic force elements 762a, 762b.

[0069] A second example of a complex reaction path is shown in Figure 10A. Figure 10D shows the resulting complex force response curve 818. In particular, it should be noted that the complex reaction path in the example of Figure 10A includes a combination of type A force elements 862a and type B force elements 862b, with the individual force response curves 818a of type A force element 862a shown in Figure 10C and the individual force response curves 818b of type B force element 862b shown in Figure 10B. In the exemplary embodiment of Figure 10A, the force elements have a permanent magnetic field connected to the permanent magnetic field of the mass block 812. However, it should be noted that in alternative embodiments, a complex force response curve 818 equivalent to that shown in Figure 10D can be realized by a combination of spring elements, such as those shown in Figures 2C and 5D. Here again, the resulting force response curve 818 can be a more important characteristic defining the linear actuator than the details of the elements used to form the combined force response curve 818, and therefore, the focus can be on the definitive features of the combined force response curve 818. First, we look at the strengths and weaknesses of the force response curves 818a and 818b of the individual force elements 862a and 862b that form the reaction force paths.

[0070] In fact, it is worth recalling that the B-type force element 862b can offer the advantage of having a region of increasing return force on the first side of the rest position 816b, a region of increasing return force on the second side of the rest position 816b, and a plateau region between them (see Figure 5B for details). The presence of two opposite regions of increasing return force may be advantageous in some embodiments of tactile linear actuators. This is due to the fact that these can allow a mass to be effectively trapped between them. However, a low slope at the intersection of the force response curve 818b and the rest position 816b (which is the zero force point in this force response curve 818b) may be undesirable. This is because it may lead to a mass being held more loosely in its rest position 816b than in embodiments where the slope would be higher when the linear actuator is inactive.

[0071] Furthermore, it is worth noting that the A-type force element 862a offers the advantage of having a more pronounced slope at the rest position 816a, in the context of having a more stable slope in the plateau region it provides and being offset from the zero force line. However, the A-type force element 862a has only one region of increasing return force, and the lower force acting on the other side may not satisfactorily trap the mass in the intended linear displacement path.

[0072] In the composite force response curve 818 presented in Figure 10D, it can be seen that by combining the A-type force response curve 818a and the B-type force response curve 818b, the advantages of both force response curves 818a and 818b can be added together in a way that eliminates or mitigates their individual disadvantages. In fact, the composite force response curve 818 can have two regions of increasing return force 864 and 866, each connected to the corresponding ends 828 and 836 of a linear displacement path 824 associated with the corresponding point of maximum return force, with a plateau region 842 between the regions of increasing return force 864 and 866. Furthermore, the slope across the rest position 816 can be higher than that which would be in the B-type force response curve (e.g., force response curve 818b shown in Figure 10B). The longitudinal range of the plateau region 842 can be greater than the longitudinal range of the plateau region in the B-type force response curve. The plateau region 842 can have most (if not all) of its range being very low slope and non-zero force. The shape of the composite force response curve 818 may be advantageous in tactile feedback and, furthermore, can be used in combination with energy unbalancing to generate different potential responses. In fact, it is possible to generate a strong high-frequency response region by unbalancing the force generation to the left of the stationary point 816, and a strong lower-frequency response region by unbalancing it to the right of the stationary point 816, as well as by utilizing a long plateau region and a high slope in the region of increasing return force on the right side of the plateau region 842 with a stronger unbalance to the right, in which a strong slope is used to create considerable deceleration and then acceleration of the mass 812 toward the opposite orientation.

[0073] In fact, looking more specifically at the exemplary composite force response curve 818 presented in Figure 10D, it can be seen that the maximum return forces at both ends 828, 836 can be significantly higher, for example, more than twice, three times, five times, or even eight times the level of force reached in the plateau region 842. The plateau region 842 can extend to at least the linear displacement distance over either (in fact, both in this case) of the increasing return force regions 864, 866, or even at least 1.5 times or more of that linear displacement distance. The slope can be defined as defined above in units where the maximum return force of the linear actuator is given a value of 1 and half of the total span of the linear displacement path is given a value of 1. Using this definition, the region of increasing return force 866 to the left of the rest position 816, or the region of increasing return force 864 to the right of the rest position 816, may have a slope where it remains above 1 for more than 3 / 4 of its span (and even over its entire span), while the plateau region 842 may have a slope where it remains between zero and 1 (and even below 0.5) for more than 3 / 4 of its span (and even over its entire span). Furthermore, the return force in the plateau region 842 may remain between 5% and 20% of the maximum return force for more than 3 / 4 of its span. This plateau region 842 is an interesting feature from the perspective of motion dynamics.

[0074] In a particular embodiment presented in Figure 10A, the mass mass 812 has two magnetized portions 844a, 844b oriented oppositely, separated by a soft ferromagnetic spacer 860. The soft ferromagnetic spacer 860 can be sized in such a way as previously discussed in relation to the embodiment shown in Figure 8C that it compresses the magnetic field lines in the central region and increases the degree of their curvature. In some embodiments, this makes it possible to amplify coupling with B-type and / or A-type elements 862a, 862b (in embodiments where one or both of these elements are embodied as magnets). In some embodiments (for example, as illustrated in Figure 10A), and because the magnetic field strength typically decreases as a fourth exponential function of distance, the B-type and A-type elements 862a, 862b can interact significantly with only one of the magnetic segments 844a, 844b of the mass mass 812. However, in other embodiments, an A-type or B-type element may interact significantly with more than one magnetic segment of the mass mass. To illustrate the complexity of the possible effects of force elements on the force response curve, an embodiment can be considered in which a B-type force element positioned similarly to the B-type force element 862b presented in Figure 10A further interacts with other magnetic segments 844b. At the rest position of the second magnetized portion 844a with respect to the B-type element, the influence of the B-type elastic path element on the first magnetized portion 844a is negligible. However, if the mass mass 812 is moved to some extent to the right with respect to the A-type element 862a and the B-type element 862b, the B-type elastic path element begins to have a B-type response not only on the second magnetized portion 844b but also on the first magnetized portion 844a. Such examples can provide a very suitable broadband frequency response, which is well adapted to several embodiments (e.g., some tactile actuators).

[0075] In fact, a particular example presented in Figure 10A uses two oppositely magnetized portions 844a and 844b at the opposite end of the mass mass 812. The AB-type element 862b is associated with the rest position of the first magnetized portion 844a of the mass mass 812, inducing the force response curve 818b presented in Figure 10B. Furthermore, the A-type element 862a is provided slightly recessed from the first magnetized portion 844a, and is therefore positioned in such a manner that it has the first magnetized portion 844a of the mass mass 812 in the rest position, inducing the force response curve 818a presented in Figure 10C. The resulting force response curve 818, shown in Figure 10D, includes a high-frequency response region to the left of the rest position 816 corresponding to the increasing return force region 866, a low-frequency response region (higher power efficiency region) corresponding to the plateau region 842, and an impact or magnetic return region (shown as a dip to the right of the plateau region 842) corresponding to the increasing return force region 864. The elastic (but nevertheless strong) dip to the right of the plateau region 842 allows the force response curve 818 to be better fitted than the force response curve of an A-type element (for example, as shown in Figure 2B) by providing a more robust "end" to the linear displacement path to the right of the plateau region 842 in some embodiments.

[0076] An exemplary alternative to the embodiment presented in Figure 10A is presented in Figure 10F. In the embodiment presented in Figure 10F, the mass 812 has a single magnetic segment, but the combination of A-type and A-type magnetic elements 862a, 862b remains, continuing to provide a force response curve generally similar to the force response curve 818 presented in Figure 10D. The embodiment presented in Figure 10G is similar to the embodiment presented in Figure 10F, except that the B-type force element 862b is provided in the form of a spring element 814, as previously presented in Figure 5D.

[0077] Other methods exist for introducing a “dip” at the end of the plateau region in the force response curve resulting from the A-type force element 862a. One such method is to add a second region of increasing return force to the first region and plateau of increasing return force provided by the A-type force element. For example, in the embodiment presented in Figure 10H, the second region of increasing return force can be added by adding a repulsive magnet 868 at the second end of the linear displacement path (opposite the position of the A-type force element 862a), which can provide a hard stop for the mass block 812 depending on the size of the distance between the two. Figure 10I is a similar embodiment to that of Figure 10H, but here the repulsive magnet 868 at the second end of the linear displacement path is replaced by a magnetic force element 870, which is transversely adjacent to the linear displacement path but is still magnetically connected to the magnetic segment. The embodiment shown in Figure 10J is similar to the embodiment shown in Figure 10G, except that instead of continuous contact with the mass mass 812, a gap 872 is provided between the mass mass 812 and the B-type spring element 814. Such a gap 872 can be a way that makes better use of the potential plateau region span provided by the A-type force element 862a. The embodiment shown in Figure 10K can provide a force response curve equivalent to, for example, the force response curve of the embodiment shown in Figure 10J or Figure 10I, but uses only the spring element 814, and more specifically, a gap 878 is provided between the B-type spring element 876 and the mass mass 812 when the A-type spring element 874 is at one end and the B-type spring element 876 is at the other end of the linear displacement path, and the mass mass 812 is at a rest position defined by the A-type spring element 874. In this latter embodiment, the A-type spring element 874 can remain continuously attached to the mass mass 812.

[0078] It should be noted that the frequency response curve 820 (shown in Figure 10E) actually contains two acceleration amplitude peaks 880 and 882, which in this case are spaced apart by a frequency difference of more than 100 Hz. The two acceleration amplitude peaks 880 and 882 are separated from each other by a significant plateau region 884, which maintains the force provided within the plateau region above 50% of the maximum force (in units of G) response (provided at the frequency of the highest peak 882). Such a broadband frequency response curve 820 can be of great interest in a variety of applications. In particular, in applications where precise frequencies are not (or could otherwise not be) provided for various reasons, the force provided within the plateau 884 is sufficient for a given application, for example.

[0079] Furthermore, as shown in Figure 10E, the frequency response curve 820 may further include a foldover effect 884, which may be used in a manner similar to that described above in relation to Figure 5C.

[0080] Furthermore, more complex frequency response behaviors can be achieved by combining additional force elements, resulting in a vast number of potential combinations. One example is presented in Figure 11A, where the individual A-type and B-type elements 962a, 962b are arranged similarly to the A-type and B-type elements 862a, 862b presented in Figure 10A, but here both of these elements are hybrid permanent magnet / electromagnet elements, where the electromagnet portion can be selectively turned on, turned off, or even operated in reverse polarity to produce a significant effect on the force response curve. Moreover, another A-type element 962c having a structure similar to that previously presented with reference to Figure 4A can be added to the equilibrium position relative to the second magnetic segment 944b, making it possible to create an even sharper slope to the left of the rest position in the corresponding force response curve compared to the force response curve 818 relating to the embodiment presented in Figure 10A.

[0081] In the modified configuration shown in Figure 11A, the B-type and A-type force elements 962a and 962b associated with the first magnetized portion 944a are combinations of permanent magnets and electromagnets 910. More specifically, each electromagnet 910 can be selectively activated to significantly attenuate (or significantly amplify) the magnetic field of the associated permanent magnet. Thus, the force response curve 818 in Figure 10D is achieved by activating the electromagnets to significantly amplify the magnetic field of the permanent magnet. In the operating mode illustrated in Figure 11A, the polarity of the electromagnet of the B-type force element 962b is reversed, which can essentially cancel out the effect of the B-type force element in the overall force response curve 918a, while the original polarity of the electromagnet 910 of the A-type force element 962a is maintained, which can be used to selectively increase the high-frequency response, as shown in Figure 11B, which is indicated by an increase in the amplitude of the high-frequency response peak 982a at the expense of the amplitude of the lower-frequency response peak 980a. Figure 11B shows the frequency response curve 920a of the embodiment shown in Figure 11A, in comparison to the frequency response curve 820 previously discussed in relation to Figure 10E.

[0082] Figure 12A presents another potential operating mode of the same device, where the polarities of both the electromagnet of the type B force element 962b and the electromagnet of the type A force element 962a are reversed, canceling out both of their individual effects in the overall force response curve 918b. Such an approach makes it possible to produce the effect of strongly increasing the amplitude of the low frequency response peak 980b at the expense of the amplitude of the high frequency response peak 982b, as presented in the frequency response curve 920b presented in Figure 12B. Such a response may be useful, for example, in the context of impact tactile feedback. Figure 12B shows the frequency response curve 920b of the embodiment shown in Figure 12A, compared with the frequency response curve 820 previously discussed in relation to Figure 10E.

[0083] The intermediate effect can be achieved by switching the electromagnet 910 off, or, for example, by operating it at an intermediate strength instead of completely reversing its polarity.

[0084] Several exemplary alternative embodiments can be provided that can achieve a suitable force response curve. Figure 13A presents an embodiment that can have some similar behavior to the force response curve of the embodiment presented in Figure 5F, for example, but the addition of an auxiliary, relatively low-force attractive magnet 1090 at one end of the mass mass 1012, as shown on the left of Figure 13A, can potentially impart greater asymmetry (and even a longer-span plateau region) to the resulting force response curve. As can be seen, to further aid the asymmetry, a corresponding opposite auxiliary, relatively low-force repulsive magnet 1092 may be present at the opposite end of the mass mass 1012. In alternative embodiments, it will be understood that only one of the attractive magnet 1090 or the repulsive magnet 1092 may be used without departing from the present disclosure. In the embodiment presented in Figure 13B, the resulting force response curve is similar to that provided by the embodiment presented in Figure 10J, except that the magnetic element 1011 is present only on the first lateral side of the mass mass 1012 and is therefore not "balanced". Balancing is achieved by a linear guide (not shown). Furthermore, the coil 1096 may be oriented transversely to the linear displacement path 1024 rather than being coiled around the linear displacement path 1024, and still generate a driving force by magnetic coupling with the magnetic segment of the mass mass 1012. The two latter features may be used individually or combined, for example, to modify some of the exemplary embodiments presented herein without departing from this disclosure. Many more other potential modifications are possible.

[0085] Figure 14A presents an exemplary embodiment of the linear actuator 1100, which is based entirely on the concept of reaction force paths presented in Figure 10A. It is noted here that the mass mass 1112 has an obround or “racetrack” cross-sectional shape, and that the A-type 1162a and B-type 1162b permanent magnet elements are configured accordingly on the opposite horizontal transverse sides 1190a, 1190b of the mass mass 1112, with concave semicircular recesses matching the convex semicircular transverse sides 1190a, 1190b of the mass mass 1112. Figure 14B shows the mass mass 1112 alone. In this embodiment, the longer first portion 1192 of the mass mass 1112 has a sequence of two magnetic segments 1144a, 1144b of opposite polarity, spaced apart from each other by a ferromagnetic spacer 1160. In the rest position illustrated in Figure 14A, the coil 1194 is aligned transversely and longitudinally overlaps the ferromagnetic spacer 1160. The first portion 1192 also has a mass segment 1196a at one end. The purpose of the mass segment 1196a can be both to act as a guide in cooperation with the magnetic force elements 1162a and 1162b, and to add mass to the mass block 1112 for increased force response. The first portion 1192 of the mass block 1112 has a first width 1197. In this embodiment, the second portion 1198 of the mass block 1112 has a larger second width 1199 and is formed entirely by the mass segment 1196b. The larger second width 1199 can act as a hard stop in cooperation with the plastic housing, which otherwise closely matches the shape of the component (not shown).Maintaining a narrow first mass segment 1196a as an extension of the first portion 1192 (or otherwise as part of the first portion 1192) can facilitate assembly by allowing the mass mass 1112 to be introduced into the linear path formed by the coil 1194, and by allowing the magnetic force elements 1162a, 1162b to be introduced to the rest position from the side having a narrower first width 1197, for example.

[0086] The two mass segments 1196a and 1196b may be made from any material desirable for a given application. For example, in certain embodiments, it may be desirable that the material be optimized to have high density while avoiding materials that would incur high costs. Such materials may be non-ferrous materials (e.g., tungsten). It is further understood that the mass segments 1196a and 1196b may be made from multiple materials that engage with each other to ultimately form the mass segments 1196a and 1196b. For example, in some embodiments, it may be desirable that the mass segments have an inner core made from a high-density material, which may have more brittle material properties compared to, for example, an outer layer material surrounding the inner core material, or the inner core material may also be a high-density material, but have increased malleability or full-circumference durability compared to the core material. It is further understood that the mass segments 1196a and 1196b may be made from different materials, or may have different structures while being made from the same material, without departing from the present disclosure.

[0087] Figure 16 is a schematic diagram of an electronic device 1200 incorporating a controller 1202 and a linear actuator 1204. The controller 1202 may be used to control the drive force generator of the linear actuator 1204. In one embodiment, the controller 1202 may have some form of processor and some form of memory, and therefore may be a computer. The controller 1202 may be used to drive the coil element of the linear actuator 1204 according to drive signals, for example, as previously presented in Figures 3B to 3E. In this particular embodiment, the electronic device 1200 is a mobile phone 1206 having a screen 1208. It will be understood that the electronic device 1200 may be any other type of electronic device, which may include or omit the screen 1208.

[0088] It will be understood that the term “computer” as used herein should not be interpreted in a restrictive manner. Rather, it is used in a broad sense, generally referring to a combination of one or more processors of some form and some form of memory accessible by those processors. The memory system can be of a non-temporary type. The use of the singular form of “computer” as used herein includes a combination of two or more computers working together to perform a given function. Furthermore, the use of the term “computer” as used herein includes the use of a partial capacity of a given processor.

[0089] A schematic example of computer 1300 is shown in Figure 15, which may generally include a processor 1302, memory 1304, and an input / output interface 1306.

[0090] The processor 1302 can be embodied in several forms, including, but not limited to, a general-purpose microprocessor or microcontroller, a digital signal processing (DSP) processor, an integrated circuit, a field-programmable gate array (FPGA), a reconfigurable processor, and a programmable read-only memory (PROM).

[0091] Memory 1304 is located either internally or externally and can include any suitable combination of suitable types of computer-readable memory that are accessible by the processor either directly or via a network (e.g., the Internet) in a wired or wireless manner. Computer-readable memory can be embodied in the form of, to name a few, random access memory (RAM), read-only memory (ROM), compact disk read-only memory (CDROM), electro-optical memory, magneto-optical memory, erasable programmable read-only memory (EPROM), and electrically erasable programmable read-only memory (EEPROM), Ferroelectric RAM (FRAM®).

[0092] Computer 1300 has one or more input / output (I / O) interfaces 1306 which can enable communication with a human user and / or with another computer via associated inputs, outputs, or input / output devices (e.g., keyboard, mouse, touchscreen, antenna, port, etc.). Each I / O interface can enable the computer to perform other computing tasks by communicating with other components and / or exchanging data, by accessing and connecting to network resources, by enabling the computer to perform application roles, and / or by connecting to networks (or multiple networks) that can carry data. Networks include, to name a few, the Internet, Ethernet, Basic Telephone Service (POTS) lines, Public Switched Telephone Network (PSTN), Integrated Digital Network (ISDN), Digital Subscriber Line (DSL), coaxial cable, fiber optic, satellite, mobile, wireless (e.g., Wi-Fi, Bluetooth, WiMAX), SS7 signaling networks, fixed lines, local area networks, and wide area networks.

[0093] It will be understood that the computer 1300 is capable of performing functions or processes through hardware, or through a combination of both hardware and software. For example, the hardware may include logic gates included as part of the processor's silicon chip. The software (e.g., applications, processes) may be in the form of data, such as computer-readable instructions 1308, stored in non-temporary computer-readable memory accessible by one or more processing units. With respect to the computer or processing unit, the expression “configured to” refers to the presence of hardware, or a combination of hardware and software, capable of operating to perform the relevant function.

[0094] For the sake of clarity, the examples described and illustrated above are intended to be illustrative only.

[0095] For example, other types of linear actuators besides tactile actuators can benefit from reaction force paths or force elements as presented above. Furthermore, there are many ways of implementing linear guides that can provide the ability of a mass to move along a linear displacement path, while at the same time limiting the ability to move along the linear displacement path. Several examples are shown in Figures 17A to 17D. Figure 17A shows an example of a slide guide 1400, where the entire perimeter (or dedicated portion thereof) of both the slide guide 1400 and the mass 1412 is configured to slide tightly relative to each other along the entire linear displacement path 1424. In such embodiments, the linear guide 1400, the mass 1412, or both can have a particular fit, or otherwise have a configuration that limits the amount of friction during sliding movement. Some plastics (e.g., Teflon®) can exhibit such low-friction behavior when sliding against some metals. Figure 17C shows some similarities to the embodiment in Figure 17A, but here a roller bearing 1406 is used to form a low-friction sliding interface between the mass block 1412 and the linear guide.

[0096] Figure 17B presents another example in which a mass 1412 is “suspended” by a plurality of individual bends 1402, which can be, for example, metal or elastomer spring elements. The bends 1402 are capable of elastically yielding as the mass 1412 moves along a linear displacement path, and on the other hand, are relatively rigid in terms of otherwise maintaining the mass in a state aligned with the linear displacement path 1424. In some embodiments, such “bends” 1402 can be part of one or more force elements that further contribute to defining or defining the reaction force path (and, more specifically, the force response curve), and in some embodiments, they can constitute a single force element. The embodiment presented in Figure 17D may have some similarities to the embodiment in Figure 17B, where an elastic membrane 1404 may be used instead of the elastic bends 1402. When used in such a context to guide and constrain the movement of a mass 1412 along a linear displacement path 1424, the bent portion 1402 and the membrane 1404 can be considered to form a type of linear guide.

[0097] It should be noted that in the embodiments illustrated in the attached drawings, the north pole of the magnet is conventionally associated with the head of the arrow. However, it will be understood that in many embodiments, the north and south poles can all be interchanged without significantly affecting the operation of the embodiment.

[0098] Therefore, its scope is indicated by the attached claims.

Claims

1. A linear actuator, The linear actuator is A mass mass that is movable within a linear displacement path, wherein the mass mass has a magnetic segment, A driving force generator configured to selectively apply acceleration to the mass along the path direction of the linear displacement path, A reaction force path that generates a return force when the mass is displaced from the rest position, Includes, The return force is directed towards the rest position along the path direction of the linear displacement path, The amplitude of the return force changes as a function of the position of the mass in the linear displacement path according to the force response curve. The reaction force path includes a permanent magnet element, The permanent magnet element is arranged transversely along the linear displacement path and is magnetically connected to the magnetic segment. A linear actuator characterized in that the magnetic segment is a first magnetic segment, the mass mass further comprises a second magnetic segment separated from the first magnetic segment in the direction of the linear displacement path by a spacer of ferromagnetic material, the two magnetic segments each have a corresponding permanent magnetic field, each permanent magnetic field is oriented parallel to the linear displacement path, and each permanent magnetic field is oriented in opposite directions along the linear displacement path.

2. A linear actuator according to claim 1, characterized in that the driving force generator is an electromagnet arranged adjacent to the linear displacement path in the transverse direction.

3. A linear actuator according to claim 2, wherein the electromagnet is aligned transversely with the spacer when the mass is in the rest position.

4. A linear actuator according to claim 1, characterized in that the permanent magnetic force element has a permanent magnetic field oriented parallel to the linear displacement path.

5. A linear actuator according to claim 4, characterized in that the permanent magnet element is longitudinally adjacent to the first or second magnetic segment when the mass is in the rest position, and the permanent magnetic field of the permanent magnet element is oriented in the same direction as the permanent magnetic field of the first or second magnetic segment.

6. A linear actuator according to claim 5, wherein the permanent magnet element is given by equation y = b ｘ A linear actuator characterized by showing individual force response curves whose shape is determined as a part of a curve formed by an exponential function formed by -1, wherein the position x=0 corresponds to the rest position of the force response curve.

7. A linear actuator according to claim 5, wherein the reaction path further includes a second permanent magnet element, the second permanent magnet element being of type y = (x ３ A linear actuator characterized by showing a second individual force response curve whose shape is determined as a part of a curve formed by a cubic polynomial function of ), wherein the part of the curve is concentrated at x=0, and the position of x=0 corresponds to the rest position of the force response curve.

8. A linear actuator according to claim 4, characterized in that the permanent magnetic force element is aligned transversely with the first or second magnetic segment when the mass is in the rest position, and the permanent magnetic field or the permanent magnetic force element is oriented in the opposite direction to the permanent magnetic field of the first or second magnetic segment.

9. A linear actuator according to claim 8, wherein the permanent magnet element is of type y = (x ３ A linear actuator characterized by showing a first individual force response curve whose shape is determined as a part of a curve formed by a cubic polynomial function of ), wherein the part of the curve is concentrated at x=0, and the position of x=0 corresponds to the rest position of the force response curve.

10. A linear actuator according to claim 8, wherein the linear actuator further includes a second permanent magnetic force element having a second permanent magnetic field oriented parallel to the linear displacement path, wherein the second permanent magnetic force element is longitudinally adjacent to the first or second magnetic segment when the mass is in the rest position, and the permanent magnetic field of the second permanent magnetic force element is oriented in the same direction as the permanent magnetic field of the first or second magnetic segment.

11. A linear actuator according to claim 1, wherein the permanent magnet element is a first permanent magnet element and further comprises a second permanent magnet element, each permanent magnet element having a permanent magnetic field oriented parallel to the linear displacement path, the first permanent magnet element being longitudinally adjacent to the first or second magnetic segment when the mass is in the rest position, the permanent magnetic field of the first permanent magnet element being oriented in the same direction as the permanent magnetic field of the first or second magnetic segment, the second permanent magnet element being transversely aligned with the first or second magnetic segment when the mass is in the rest position, and the permanent magnetic field or the second permanent magnet element being oriented in the opposite direction to the permanent magnetic field of the first or second magnetic segment.

12. A linear actuator according to claim 11, characterized in that the force response curve has a region of increasing return force related to the opposite end of the linear displacement path and a plateau region located between the regions of increasing return force.

13. A linear actuator according to claim 11, wherein the driving force generator is an electromagnet disposed adjacent to the linear displacement path in the transverse direction, and the electromagnet is aligned with the spacer in the transverse direction when the mass is in the rest position.

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