Pedal device

Abstract

A pedal arm (3) is supported so as to be rotatable on a predetermined rotation axis (CL) with respect to a housing (2), and is operated as being stepped on by a driver. A reaction force generation mechanism (4) applies, to the pedal arm (3), a reaction force against a stepping force of the driver acting on the pedal arm (3). A hysteresis generation mechanism (5) is a separate mechanism independent of the reaction force generation mechanism (4), and has a sliding member (50) and a biasing member (60). The sliding member (50) slides against a sliding surface (SS) of the housing (2), a housing-side component (29) fixed to the housing (2), the pedal arm (3), or a part of a pedal-side component (80) moving together with the pedal arm (3). The biasing member (60) biases the sliding member (50) toward the sliding surface (SS) in a direction parallel to the rotation axis (CL) of the pedal arm (3).

Description

Pedal device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2024-153919, filed on September 6, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a pedal device mounted on a vehicle.

[0003] BACKGROUND ART Conventionally, pedal devices such as accelerator pedal devices or brake pedal devices are known to be used in by-wire systems in which an electronic control device controls the acceleration and deceleration of a vehicle based on an output signal from a sensor that detects the pedal stroke.

[0004] The pedal device described in Patent Document 1 includes a pedal arm rotatably mounted on a housing attached to a vehicle body, a return spring that applies a reaction force to the pedal arm in response to the driver's pedal force, and a hysteresis mechanism that imparts hysteresis to the reaction force. In Patent Document 1, the housing is referred to as a bracket. The hysteresis mechanism includes a stay fitted to the outside of the pedal arm and a torsion coil spring. The stay is integrally formed with a cylindrical portion that fits to the outside of the pedal arm and a protruding piece that extends tangentially to the cylindrical portion. A cushioning material serving as a sliding member is fixed to the surface of the protruding piece facing the housing. The torsion coil spring is fitted to the outside of the pedal arm. One end of the coil wire is engaged with the pedal arm, and the other end of the coil wire is engaged with the protruding piece, biasing the protruding piece and the sliding member against the side of the housing. With this configuration, when the driver applies a pedal force to the pedal arm, the frictional force generated by the sliding of the sliding member and the housing imparts a predetermined hysteresis characteristic to the reaction force of the return spring.

[0005] Japanese Patent Application Laid-Open No. 2000-326753

[0006] However, the pedal device described in Patent Document 1 is configured such that the other end of the coil wire of the torsion coil spring biases the protruding piece of the stay in the circumferential direction of the coil. Therefore, the biasing force of the torsion coil spring may cause the cylindrical portion of the stay and the axis of the pedal arm to move away from the housing, causing the sliding member to contact the housing at an angle. This changes the vertical load of the sliding member on the housing (i.e., the normal force of the housing) and reduces the contact area between the housing and the sliding member. Furthermore, dimensional variations in the other end of the torsion coil spring and the protruding piece of the stay may change the contact position between the housing and the sliding member. This causes fluctuations in the hysteresis reaction force, which in turn causes fluctuations in the pedal force characteristics and abnormal wear of the sliding member and the housing. Therefore, this pedal device may deteriorate the pedal feel and vehicle operability.

[0007] An object of the present disclosure is to provide a pedal device that can stabilize pedal force characteristics and improve pedal feel and vehicle operability.

[0008] According to one aspect of the present disclosure, a pedal device mounted on a vehicle includes: a housing attached to the vehicle; a pedal arm rotatably supported on the housing around a predetermined rotation axis and operated by a driver when the pedal arm is depressed; a reaction force generating mechanism that applies a reaction force to the pedal arm in response to the driver's depression force acting on the pedal arm; and a hysteresis generating mechanism that is an independent mechanism separate from the reaction force generating mechanism and generates a hysteresis characteristic in which the reaction force when the pedal is depressed is greater than the reaction force when the pedal is released over a predetermined pedal stroke, wherein the hysteresis generating mechanism has: a sliding member that slides against a sliding surface of the housing, or a housing-side component fixed to the housing, or the pedal arm, or a part of a pedal-side component that operates together with the pedal arm; and a biasing member that biases the sliding member toward the sliding surface in a direction parallel to the rotation axis of the pedal arm.

[0009] According to this, the biasing member biases the sliding member in a direction parallel to the rotation axis of the pedal arm, thereby reducing the change in the position of the sliding member when it contacts the sliding surface, and the sliding member contacts the sliding surface in a stable position. This prevents unintended changes in the vertical load on the sliding surface (i.e., the load that generates the hysteresis reaction force). This stabilizes the hysteresis characteristics (i.e., the pedal force characteristics) and reduces abnormal wear on the sliding surface and sliding member, improving the pedal feel and vehicle operability.

[0010] Furthermore, by making the hysteresis generating mechanism an independent mechanism separate from the reaction force generating mechanism, it is possible to design hysteresis characteristics (i.e., pedal force characteristics) that are less dependent on pedal force. Specifically, it is possible to design hysteresis characteristics that keep the hysteresis reaction force substantially constant from the initial position of the pedal stroke to all pedal positions, and it is also possible to design hysteresis characteristics that change the hysteresis reaction force as intended depending on the pedal stroke. Note that in this disclosure, "parallel" includes not only perfect parallelism but also substantial parallelism (e.g., an error of about ±5°) due to manufacturing tolerances of parts, etc.

[0011] 11 is a cross-sectional view of the pedal device according to the first embodiment. FIG. 12 is a bottom view of the pedal device taken along line II in FIG. 1. FIG. 13 is a cross-sectional view taken along line III-III in FIG. 1. FIG. 14 is a graph showing the pedal force characteristics of the pedal device according to the first embodiment. FIG. 15 is an image of line V-V in FIG. 3. FIG. 16 is a perspective view of a pedal device according to a comparative example. FIG. 17 is a view taken along line VII in FIG. 6, with the ring member removed. FIG. 18 is an image of line VIII-VIII in FIG. 7. FIG. 19 is a cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a second embodiment. FIG. 19 is a cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a third embodiment. FIG. 19 is a perspective view of a pedal arm included in a pedal device according to a fourth embodiment. FIG. 11 is an arrow view taken along line XII in FIG. 11. FIG. 19 is an explanatory view for explaining an assembly method of the hysteresis generating mechanism included in the pedal device according to the fourth embodiment. FIG. 19 is a cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a fifth embodiment. FIG. 20 is a graph showing the pedal force characteristics when the hysteresis generating mechanism included in the pedal device according to the fifth embodiment does not have an elastic member. 21 is a cross-sectional view of a sliding member of a hysteresis generating mechanism included in a pedal device according to a sixth embodiment. 22 is a cross-sectional view of a pedal device according to a seventh embodiment. 23 is a cross-sectional view taken along line XVIII-XVIII in FIG. 17. 24 is a graph showing the pedal force characteristics of a pedal device according to a seventh embodiment. 25 is a cross-sectional view of a portion corresponding to FIG. 18 in a hysteresis generating mechanism included in a pedal device according to an eighth embodiment. 26 is a cross-sectional view of a pedal device according to a ninth embodiment. 27 is a cross-sectional view taken along line XXII-XXII in FIG. 21. 28 is a graph showing the pedal force characteristics of a pedal device according to a ninth embodiment. 29 is a cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a tenth embodiment. 29 is an explanatory view for explaining a method of assembling a housing, a pedal arm, and a hysteresis generating mechanism. 29 is a cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to an eleventh embodiment. 29 is an explanatory view for explaining a method of assembling the hysteresis generating mechanism. 29 is a cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a twelfth embodiment.34 is an explanatory diagram for explaining an example of a state during operation of a hysteresis generating mechanism included in a pedal device according to a twelfth embodiment. A cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a thirteenth embodiment. A cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a fourteenth embodiment. A cross-sectional view of a portion corresponding to FIG. 3 in a hysteresis generating mechanism included in a pedal device according to a fifteenth embodiment. A cross-sectional view of a pedal device according to a sixteenth embodiment. A cross-sectional view of a pedal device according to a seventeenth embodiment. A cross-sectional view taken along line XXXV-XXXV in FIG. 34. A cross-sectional view of a pedal device according to an eighteenth embodiment in a state where the pedal arm is in an initial position. A cross-sectional view of a pedal device according to an eighteenth embodiment in a state where the pedal arm is in a fully depressed position.

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following embodiments, identical or equivalent parts will be denoted by the same reference numerals, and description thereof will be omitted.

[0013] In the first embodiment, a brake pedal device used in a brake-by-wire system for a vehicle will be described as an example of the pedal device. The brake-by-wire system is a system in which an electronic control device controls the deceleration of a vehicle based on an output signal from a sensor that detects the amount of depression of a pedal arm (i.e., pedal stroke).

[0014] 1 and 2 , the pedal device 1 includes a housing 2, a pedal arm 3, a reaction force generating mechanism 4, and a hysteresis generating mechanism 5. The pedal device 1 of the first embodiment is of a so-called pendant type, in which a pedal pad 31, which is the part of the pedal arm 3 that is stepped on by the driver, is disposed below the vehicle with respect to the rotation axis CL of the pedal arm 3 when mounted on the vehicle.

[0015] The housing 2 may be attached directly to the vehicle, or may be attached to the vehicle via a plate (not shown) or the like. A shaft 32 is rotatably provided relative to the housing 2. The pedal arm 3 is fixed to the shaft 32. Therefore, the housing 2 supports the pedal arm 3 rotatably with the axis of the shaft 32 serving as a rotation axis CL. Alternatively, the housing 2 and the shaft 32 may be fixed, and the pedal arm 3 may be rotatably provided relative to the shaft 32. Hereinafter, the direction parallel to the rotation axis CL may be referred to as the "rotation axis direction."

[0016] The housing 2 has a first side wall portion 21 provided on one side in the rotational axis direction with respect to the pedal arm 3, a second side wall portion 22 provided on the other side in the rotational axis direction, and first to third connection portions 23, 24, 25 connecting the first side wall portion 21 and the second side wall portion 22. The first connection portion 23 is a portion that faces upward in the vehicle when mounted on the vehicle, the second connection portion 24 is a portion that faces downward in the vehicle, and the third connection portion 25 is a portion that faces the driver.

[0017] The pedal arm 3 is supported by the housing 2 so as to be rotatable around a predetermined rotation axis CL. The pedal arm 3 is disposed between the first side wall portion 21 and the second side wall portion 22 of the housing 2. The pedal arm 3 has a pedal pad 31, which is a portion that is stepped on by the driver, at the end opposite the rotation axis CL. The pedal arm 3 is depressed by the driver's pedal force applied to the pedal pad 31. The direction in which the pedal arm 3 moves as the driver's pedal force increases is referred to as the "depression direction," and the direction in which the pedal arm 3 moves as the driver's pedal force decreases is referred to as the "release direction." FIG. 1 shows a state in which the driver's pedal force is not being applied to the pedal arm 3 and the pedal arm 3 is in its initial position. In this state, a stopper 33 provided on the pedal arm 3 abuts against the third connection portion 25.

[0018] The reaction force generating mechanism 4 is a mechanism that applies a reaction force to the pedal arm 3 in response to the pedal force applied by the driver to the pedal arm 3. In the first embodiment, the reaction force generating mechanism 4 is configured, for example, with three compression coil springs 41, 42, and 43 and three holders 44, 45, and 46. The three compression coil springs 41, 42, and 43 are referred to as the first spring 41, the second spring 42, and the third spring 43, respectively, from the pedal arm 3 side. The first holder 44 is provided between the pedal arm 3 and the first spring 41, the second holder 45 is provided between the first spring 41 and the second spring 42, and the third holder 46 is provided between the second spring 42 and the third spring 43. The three compression coil springs 41, 42, and 43 bias the pedal arm 3 toward the initial position with a predetermined spring constant.

[0019] The amount of depression of the pedal arm 3 (i.e., pedal stroke) is detected by a sensor 6. Various types of non-contact or contact sensors can be used as the sensor 6. Examples of non-contact sensors include a Hall sensor using a Hall element and an inductive sensor using the principle of mutual induction. In the first embodiment, two sensors 6 with different detection principles are provided on the rotation shaft CL. The output signal of the sensor 6 is transmitted to an electronic control unit (not shown). The electronic control unit controls the deceleration of the vehicle in accordance with the signal.

[0020] 1 and 3 , the pedal arm 3 has a pedal arm main body 35 and a protrusion 36 that protrudes from the pedal arm main body 35 in a direction intersecting the rotation axis CL. The pedal hole 34 is a hole that penetrates the protrusion 36 of the pedal arm 3 in the rotation axis direction. The pedal hole 34 has openings on a surface of the pedal arm 3 facing one side in the rotation axis direction and a surface facing the other side in the rotation axis direction.

[0021] In the first embodiment, the hysteresis generating mechanism 5 has, for example, two sliding members 50 and a biasing member 60, which are provided inside a pedal hole 34 provided in the pedal arm 3. In other words, the hysteresis generating mechanism 5 is a mechanism independent of the reaction force generating mechanism 4. The pedal hole 34 is provided in a position on the pedal arm 3 that is a predetermined distance away from the rotation axis CL. Therefore, the hysteresis generating mechanism 5 is provided in a position that is a predetermined distance away from the rotation axis CL.

[0022] Of the two sliding members 50, the one disposed on one side of the pedal hole 34 in the rotational axis direction is referred to as the first sliding member 51, and the one disposed on the other side in the rotational axis direction is referred to as the second sliding member 52. The first sliding member 51 slides against the first side wall portion 21 of the housing 2, and the second sliding member 52 slides against the second side wall portion 22 of the housing 2. Hereinafter, the surface that slides against the sliding member 50 is referred to as the sliding surface SS. In the first embodiment, the surface of the first side wall portion 21 of the housing 2 facing the pedal arm 3 and the surface of the second side wall portion 22 facing the pedal arm 3 are the sliding surfaces SS. In the first to sixth and ninth to eighteenth embodiments, the sliding surface SS is a surface that is perpendicular to the rotational axis CL of the pedal arm 3. In this disclosure, "perpendicular" includes not only perfect perpendicularity but also substantial perpendicularity (e.g., an error of about ±5°) due to manufacturing tolerances of parts.

[0023] The biasing member 60 is disposed inside the pedal hole 34 between the first sliding member 51 and the second sliding member 52. The biasing member 60 is, for example, a compression coil spring. The compression coil spring is disposed such that its coil axis Ax is parallel to the rotation axis CL of the pedal arm 3. Therefore, the biasing member 60 biases the sliding member 50 toward the sliding surface SS of the housing 2 in a direction parallel to the rotation axis CL of the pedal arm 3. Note that in this disclosure, "parallel" includes not only perfect parallelism but also substantial parallelism (e.g., an error of about ±5°) due to manufacturing tolerances of parts. Specifically, the biasing member 60 biases the first sliding member 51 toward the first side wall portion 21 of the housing 2 and biases the second sliding member 52 toward the second side wall portion 22 of the housing 2 during depression and release of the pedal arm 3. Therefore, both the first sliding member 51 and the second sliding member 52 slide on a sliding surface SS of a part of the housing 2 when the pedal arm 3 is depressed and released. The material of the sliding member 50 and the material of the sliding surface SS of the housing 2 may be the same or different.

[0024] The sliding member 50 has a sliding end portion 53, a flange portion 54, and a spring mounting portion 55. The sliding end portion 53 is formed in a cylindrical shape, and its end surface in the axial direction is the portion that slides against the sliding surface SS. The flange portion 54 is formed such that its outer shape, facing a direction perpendicular to a direction parallel to the axis of the cylindrical sliding end portion 53 (i.e., the biasing direction of the biasing member 60), is larger than that of the sliding end portion 53. Therefore, a step is formed between the sliding end portion 53 and the flange portion 54. The flange portion 54 slides against the inner wall of the pedal hole 34. The spring mounting portion 55 is formed on the opposite side of the flange portion 54 from the sliding end portion 53. A compression coil spring serving as the biasing member 60 is fitted around the outside of the spring mounting portion 55. The sliding end portion 53 and the spring mounting portion 55 have different dimensions and shapes.

[0025] 4, the hysteresis generating mechanism 5 generates a hysteresis characteristic in which the reaction force when the pedal is depressed is greater than the reaction force when the pedal is released for a given pedal stroke. The hysteresis characteristic can also be referred to as the pedal force characteristic when the driver applies a pedal force to the pedal pad 31.

[0026] The dashed line FS in Figure 4 indicates the characteristic of the reaction force generated by the reaction force generating mechanism 4 in response to the pedal force applied by the driver to the pedal arm 3 (hereinafter referred to as the "FS characteristic"). Note that FS stands for Force-Stroke. The hysteresis generating mechanism 5 can impart to the FS characteristic a hysteresis characteristic that keeps the hysteresis reaction force substantially constant from the initial position to all pedal positions in the pedal stroke. In other words, in Figure 4, the hysteresis reaction forces H1, H2, and H3 at any position in the pedal stroke are substantially constant.

[0027] The hysteresis reaction force is expressed by the following formula 1: H=(D1 / D2)×μ×N×P (Formula 1) H: hysteresis reaction force D1: distance between the rotation axis CL and the hysteresis generating mechanism 5 D2: distance between the rotation axis CL and the pedal pad tread surface μ: coefficient of friction between the sliding surface SS and the sliding member 50 N: normal force of the sliding surface SS against the biasing force of the biasing member 60 P: number of sliding points between the sliding surface SS and the sliding member 50

[0028] In the first embodiment, the hysteresis generating mechanism 5 is provided on the pedal arm 3 at a predetermined distance D1 from the rotation axis CL. In this way, the hysteresis reaction force can be adjusted by setting the distance D1 between the rotation axis CL and the hysteresis generating mechanism 5. Therefore, by increasing the distance D1 between the rotation axis CL and the hysteresis generating mechanism 5, the biasing force of the biasing member 60 (i.e., the spring load of the compression coil spring) required for the hysteresis reaction force can be reduced. By reducing the spring load of the compression coil spring, wear on the sliding surface SS and the sliding member 50 can be suppressed, and stable hysteresis characteristics can be obtained.

[0029] 5 is an image diagram showing the surface where the end face of the sliding member 50 contacts the sliding surface SS of the housing 2 when the pedal arm 3 is depressed or released, taken along line V-V in FIG. 5 . In FIG. 5 , the surface where the end face of the sliding member 50 contacts the sliding surface SS of the housing 2 is indicated by a hatched area 50a, and the outer edge of the end face of the sliding member 50 is indicated by a dashed line 50b. When the pedal arm 3 is depressed or released, the surface where the end face of the sliding member 50 contacts the sliding surface SS of the housing 2 is considered to be slightly smaller than the end face of the sliding member 50 due to the material and frictional force of the sliding member 50. However, in the first embodiment, the biasing member 60 biases the sliding member 50 in a direction parallel to the rotation axis CL, and therefore there is little change in the position where the sliding member 50 contacts the sliding surface SS. Therefore, the difference between the surface where the end face of the sliding member 50 contacts the sliding surface SS of the housing 2 and the end face of the sliding member 50 is very small.

[0030] For comparison with the pedal device 1 of the first embodiment described above, a pedal device 100 of a comparative example will be described with reference to FIGS. 6 to 8. FIG.

[0031] As shown in FIG. 6, the pedal device 100 of the comparative example includes a housing 200, a pedal arm 300, a reaction force generating mechanism 400, a hysteresis generating mechanism 500, and the like.

[0032] The housing 200 has a mounting portion 210 that is attached to the vehicle, a first side wall portion 220 that extends rearward from one end of the mounting portion 210, and a second side wall portion 230 that extends rearward from the other end of the mounting portion 210. A shaft 320 is rotatably provided in holes provided in the first side wall portion 220 and the second side wall portion 230. A pedal arm 300 is joined by welding to a portion of the shaft 320 on the first side wall portion 220 side. The pedal arm 300 is formed of a cylindrical rod-shaped member. A pedal pad 310 is provided on one end of the pedal arm 300.

[0033] The reaction force generating mechanism 400 is composed of a first torsion coil spring 410 fitted onto the outside of the shaft 320. The first torsion coil spring 410 has one end 411 of a coil wire engaged with the second side wall portion 230 and the other end 412 of the coil wire engaged with the pedal arm 300, thereby biasing the pedal arm 300 toward the initial position. Therefore, the first torsion coil spring 410 serving as the reaction force generating mechanism 400 applies a reaction force to the pedal arm 300 in response to the pedal force applied by the driver to the pedal arm 300.

[0034] The hysteresis generating mechanism 500 includes a stay 510 fitted to the outside of the pedal arm 300 and a second torsion coil spring 520. The stay 510 integrally includes a cylindrical portion 511 fitted to the outside of the pedal arm 300 and a protruding piece 512 extending in a plate-like shape in a tangential direction of the cylindrical portion 511. The cylindrical portion 511 is fitted to the pedal arm 300 so as to be rotatable about its axis, and is prevented from coming off the pedal arm 300 by a ring member 530. A sliding member 540 is fixed to the surface of the protruding piece 512 facing the housing 200. The sliding member 540 is made of, for example, a rubber material. The second torsion coil spring 520 has a coil wire fitted to the outside of the pedal arm 300. One end 521 of the coil wire is engaged with the pedal arm 300, and the other end 522 of the coil wire is engaged with the protruding piece 512. Second torsion coil spring 520 biases protrusion 512 and sliding member 540 against first side wall 220 of housing 200. More specifically, second torsion coil spring 520 biases protrusion 512 of stay 510 in the circumferential direction of the coil by the other end 522 of the coil wire. With this configuration, when the driver applies a pedal force to pedal arm 300, the frictional force generated by the sliding member 540 and first side wall 220 sliding against each other imparts a predetermined hysteresis characteristic to the reaction force of reaction force generating mechanism 400.

[0035] FIG. 7 is a view taken along the arrow VII direction in FIG. 6 , excluding the ring member 530. As shown in FIG. 7 , when the cylindrical portion 511 of the stay 510 and the axis 110 of the pedal arm 300 move in a direction away from the housing 200 due to the biasing force of the second torsion coil spring 520, the sliding member 540 contacts the housing 200 at an angle. In this case, the biasing force with which the other end 522 of the second torsion coil spring 520 biases the protruding piece portion 512 of the stay 510 and the sliding member 540 in the circumferential direction of the coil is indicated by arrow F1. Therefore, the component of the biasing force of the second torsion coil spring 520 acting perpendicularly to the sliding surface SS of the first side wall portion 220 of the housing 200 is indicated by arrow F2. This component force corresponds to the normal force of the first side wall portion 220 against the biasing force of the second torsion coil spring 520, and changes when the direction of the biasing force of the second torsion coil spring 520 changes. Therefore, in the comparative example, when the direction of the biasing force of the second torsion coil spring 520 changes, the hysteresis reaction force changes.

[0036] FIG. 8 is an image diagram showing, along line VIII-VIII in FIG. 7 , the surface where the end face of the sliding member 540 contacts the sliding surface SS of the housing 200 when the pedal arm 300 is depressed or released. In FIG. 8 , the surface where the end face of the sliding member 540 contacts the sliding surface SS of the housing 200 is indicated by a hatched area 550, and the outer edge of the end face of the sliding member 540 is indicated by a dashed line 560. In the comparative example, the second torsion coil spring 520 biases the sliding member 540 in the circumferential direction of the coil wire, so that the sliding member 540 contacts the sliding surface SS at an angle. Therefore, when the pedal arm 300 is depressed or released, the surface where the end face of the sliding member 540 contacts the sliding surface SS of the housing 200 is thought to be much smaller than the end face of the sliding member 540. Furthermore, dimensional variations in the second torsion coil spring 520 and the protruding piece 512 of the stay 510 may cause the position where the housing 200 and the sliding member 540 come into contact to change. This changes the vertical load of the sliding member 540 on the housing 200 (i.e., the normal force of the housing 200). This causes unintended fluctuations in the hysteresis characteristics (i.e., the pedal force characteristics), and further causes abnormal wear of the sliding member 540 and the housing 200. Therefore, the pedal device 100 of the comparative example may cause deterioration in the pedal feel of the pedal device 1 and the operability of the vehicle.

[0037] In comparison with the pedal device 100 of the comparative example described above, the pedal device 1 of the first embodiment has the following advantages due to its configuration.

[0038] (1) The hysteresis generating mechanism 5 included in the pedal device 1 of the first embodiment includes a sliding member 50 that slides on a sliding surface SS, which is a part of the housing 2, and a biasing member 60 that biases the sliding member 50 toward the sliding surface SS in a direction parallel to the rotation axis CL of the pedal arm 3. As a result, the biasing member 60 biases the sliding member 50 in a direction parallel to the rotation axis CL of the pedal arm 3, reducing changes in the orientation of the sliding member 50 when it contacts the sliding surface SS, and the sliding member 50 contacts the sliding surface SS in a stable orientation. This prevents unintended changes in the vertical load of the biasing member 60 on the sliding surface SS (i.e., the normal force of the sliding surface SS). This stabilizes the hysteresis characteristics and reduces abnormal wear on the sliding surface SS and the sliding member 50, improving the pedal device 1's pedal feel and vehicle operability. Furthermore, by making the hysteresis generating mechanism 5 an independent mechanism separate from the reaction force generating mechanism 4, it is possible to design a hysteresis characteristic (i.e., a pedal force characteristic) that is less dependent on the pedal force. Specifically, it is possible to design a hysteresis characteristic that keeps the hysteresis reaction force substantially constant from the initial position of the pedal stroke to all pedal positions. Note that it is also possible to design a hysteresis characteristic that changes the hysteresis reaction force as intended depending on the pedal stroke, as in the seventh to ninth embodiments described below.

[0039] (2) In the first embodiment, the pedal device 1 includes a sensor 6 that detects a pedal stroke. According to this, the pedal device 1 is used in a by-wire system in which the pedal arm 3 is not mechanically connected to a master cylinder, a wire rope, or the like, and an electronic control device controls the acceleration and deceleration of the vehicle based on an output signal from the sensor 6.

[0040] (3) In the first embodiment, the hysteresis generating mechanism 5 is provided at a predetermined distance D1 from the rotating shaft CL. Increasing the distance D1 between the rotating shaft CL and the hysteresis generating mechanism 5 reduces the biasing force of the biasing member 60 (i.e., the spring load of the compression coil spring) required for the hysteresis characteristics. This reduces wear on the sliding surface SS and the sliding member 50, thereby achieving stable hysteresis characteristics. Increasing the distance D1 between the rotating shaft CL and the hysteresis generating mechanism 5 also prevents wear particles generated by the hysteresis generating mechanism 5 from accumulating around the rotating shaft CL and affecting the hysteresis characteristics.

[0041] (4) In the first embodiment, the biasing member 60 is a compression coil spring, and the coil axis Ax of the compression coil spring is arranged parallel to the rotation axis CL of the pedal arm 3. As a result, the biasing member 60 can bias the sliding member 50 in a direction parallel to the rotation axis CL of the pedal arm 3.

[0042] (5) In the first embodiment, the sliding member 50 and the biasing member 60 of the hysteresis generating mechanism 5 are provided on the pedal arm 3. The hysteresis generating mechanism 5 is configured such that the biasing member 60 biases the sliding member 50 toward the sliding surface SS of a part of the housing 2 when the pedal arm 3 is depressed and released. This allows the hysteresis generating mechanism 5 to generate a hysteresis reaction force both when the pedal arm 3 is depressed and released, thereby stabilizing the hysteresis characteristics. This improves the pedal feel of the pedal device 1 and the operability of the vehicle.

[0043] (6) In the first embodiment, the pedal hole 34 provided in the pedal arm 3 has openings on both surfaces facing one side in the rotational axis direction and the other side. The hysteresis generating mechanism 5 is configured such that the biasing member 60 and the sliding member 50 are provided inside the pedal hole 34, and the biasing member 60 biases the sliding member 50 toward the sliding surface SS of the housing 2. This allows two sliding locations to be obtained with one biasing member 60. Therefore, based on the above formula 1, the hysteresis reaction force can be made larger relative to the biasing force of one biasing member 60. In other words, the biasing force of the biasing member 60 can be made smaller relative to the hysteresis reaction force.

[0044] (7) In the first embodiment, the material of the sliding member 50 and the material of the sliding surface SS of the housing 2 may be the same or different. This allows the hysteresis reaction force to be designed as desired depending on the friction coefficient and characteristics of the materials of each member.

[0045] (Second to Eighteenth Embodiments) The second to eighteenth embodiments are different from the first embodiment in that the hysteresis generating mechanism 5 or its peripheral configuration is modified, but the rest is the same as the first embodiment, so only the parts that are different from the first embodiment will be described.

[0046] Second Embodiment A second embodiment will now be described. As shown in Fig. 9 , in the second embodiment, the pedal hole 34 provided in the pedal arm 3 has an opening on a surface of the pedal arm 3 facing one side in the rotational axis direction, and the surface facing the other side in the rotational axis direction is closed. The hysteresis generating mechanism 5 has one sliding member 50 and a biasing member 60. The sliding member 50 slides on a sliding surface SS of the first side wall portion 21 of the housing 2.

[0047] The biasing member 60 is a compression coil spring that is provided inside the pedal hole 34 and has its coil axis Ax arranged parallel to the rotation axis CL of the pedal arm 3. When the pedal arm 3 is depressed and released, the biasing member 60 biases the sliding member 50 toward the sliding surface SS of the housing 2 in a direction parallel to the rotation axis CL of the pedal arm 3.

[0048] In the second embodiment described above, the pedal arm 3 is provided with a pedal hole 34 having an opening on one side surface parallel to the rotation axis CL. The hysteresis generating mechanism 5 is configured such that the biasing member 60 and the sliding member 50 are provided inside the pedal hole 34, and the biasing member 60 biases the sliding member 50 toward the sliding surface SS of the housing 2. This configuration makes it possible to eliminate rattling of the pedal arm 3 due to the gap between the pedal arm 3 and the housing 2 using the hysteresis generating mechanism 5. Furthermore, because the hysteresis generating mechanism 5 can be configured with one biasing member 60 and one sliding member 50, the number of parts required for the sliding member 50 can be reduced compared to the first embodiment.

[0049] (Third Embodiment) A third embodiment will be described. As shown in Fig. 10 , in the third embodiment, housing holes 26 and 27 are provided in the first side wall portion 21 and the second side wall portion 22 of the housing 2, respectively. The housing hole provided in the first side wall portion 21 is referred to as the first housing hole 26, and the housing hole provided in the second side wall portion 22 is referred to as the second housing hole 27. Both the first housing hole 26 and the second housing hole 27 have openings on the pedal arm 3 side. On the other hand, in the third embodiment, no pedal hole 34 is provided in the protrusion 36 of the pedal arm 3.

[0050] The hysteresis generating mechanism 5 has two biasing members 61, 62 and two sliding members 51, 52. The first biasing member 61 and the first sliding member 51 are provided inside the first housing hole 26. The first biasing member 61 is a compression coil spring, and its coil axis Ax is arranged parallel to the rotation axis CL of the pedal arm 3. When the pedal arm 3 is depressed and released, the first biasing member 61 biases the first sliding member 51 in a direction parallel to the rotation axis CL of the pedal arm 3 toward the sliding surface SS of the pedal arm 3 that faces the first side wall portion 21.

[0051] The second biasing member 62 and the second sliding member 52 are provided inside the second housing hole 27. The second biasing member 62 is also a compression coil spring, and its coil axis Ax is disposed parallel to the rotation axis CL of the pedal arm 3. When the pedal arm 3 is depressed and released, the second biasing member 62 biases the second sliding member 52 in a direction parallel to the rotation axis CL of the pedal arm 3, toward the sliding surface SS of the pedal arm 3 that faces the second side wall portion 22.

[0052] In the third embodiment described above, the housing 2 is provided with housing holes 26, 27 that have openings on the pedal arm 3 side. The hysteresis generating mechanism 5 is configured such that the biasing member 60 and the sliding member 50 are provided inside the housing holes 26, 27, and the biasing member 60 biases the sliding member 50 against a part of the sliding surface SS of the pedal arm 3. This allows the hysteresis generating mechanism 5 to center the pedal arm 3 with respect to the sliding surfaces SS on the left and right sides of the pedal arm 3. The hysteresis generating mechanism 5 also makes it possible to eliminate any play in the pedal arm 3 due to a gap between the pedal arm 3 and the housing 2.

[0053] (Fourth Embodiment) A fourth embodiment will be described. As shown in FIGS. 11 and 12 , in the fourth embodiment, the pedal hole 34 has an attachment / detachment opening 37 that opens in a direction intersecting the rotation axis CL. Similar to the first embodiment, the hysteresis generating mechanism 5 includes one biasing member 60 and two sliding members 51 and 52 that are provided inside the pedal hole 34. As indicated by the arrow IN in FIG. 13 , the hysteresis generating mechanism 5 is attachable to and detachable from the pedal hole 34 through the attachment / detachment opening 37. Specifically, a compression coil spring serving as the biasing member 60 is disposed between the two sliding members 51 and 52, and the two sliding members 51 and 52 are brought closer to each other to compress the compression coil spring. In this state, the sliding members 51 and 52 and the biasing member 60 can be inserted into the pedal hole 34 through the attachment / detachment opening 37.

[0054] In the fourth embodiment described above, the pedal hole 34 has the attachment / detachment opening 37 that opens in a direction intersecting the rotation axis CL. The biasing member 60 and the sliding members 51, 52 are attachable to and detachable from the pedal hole 34 through the attachment / detachment opening 37. This allows the hysteresis generating mechanism 5 to be attached to the pedal hole 34 through the attachment / detachment opening 37 after the pedal arm 3 and the housing 2 are assembled.

[0055] Fifth Embodiment A fifth embodiment will be described. As shown in FIG. 14 , in the fifth embodiment, the hysteresis generating mechanism 5 includes an elastic member 56 between the inner wall of the pedal hole 34 and the sliding member 50. The elastic member 56 is formed, for example, by an O-ring, and is fitted into a groove provided on the outer periphery of the flange portion 54 of the sliding member 50. The O-ring is elastically deformable by a load acting between the inner wall of the pedal hole 34 and the sliding member 50. Therefore, the O-ring fills the gap between the inner wall of the pedal hole 34 and the sliding member 50, thereby reducing rattling between the inner wall of the pedal hole 34 and the sliding member 50.

[0056] The sliding member 50 has a tapered surface 58 formed so that the outer diameter gradually increases from the sliding end portion 53 toward the flange portion 54. By providing the tapered surface 58 on the sliding member 50, the O-ring can be moved from the sliding end portion 53 side along the tapered surface 58 into a groove provided on the outer periphery of the flange portion 54, making it easier to assemble the O-ring into the groove.

[0057] The graph in Figure 15 shows the pedal force characteristics of the pedal device 1 when the hysteresis generating mechanism 5 does not include the elastic member 56 and there is play between the inner wall of the pedal hole 34 and the sliding member 50. In this case, as shown by arrow A, when the pedal starts to be depressed, the hysteresis reaction force temporarily increases or decreases as shown by step B, causing the driver to feel uncomfortable. Also, as shown by arrow E, when the pedal is converted from a depression operation to a release operation, the hysteresis reaction force temporarily increases or decreases as shown by step F, causing the driver to feel uncomfortable. Also, as shown by arrow C, when the pedal is converted from a release operation to a depression operation, the hysteresis reaction force temporarily increases or decreases as shown by step D, causing the driver to feel uncomfortable.

[0058] In contrast, in the fifth embodiment, the hysteresis generating mechanism 5 includes an elastic member 56 provided between the inner wall of the pedal hole 34 and the sliding member 50, thereby reducing rattle between the inner wall of the pedal hole 34 and the sliding member 50. Therefore, it is possible to suppress temporary increases and decreases in the hysteresis reaction force when starting to depress the pedal, when converting from a depressing operation to a releasing operation, and when converting from a releasing operation to a depressing operation, and to prevent the driver from feeling uncomfortable.

[0059] Sixth Embodiment A sixth embodiment will be described. The sixth embodiment is a modification of the fifth embodiment. As shown in FIG. 16 , the sixth embodiment also includes a hysteresis generating mechanism 5 having an elastic member 57 between the inner wall of the pedal hole 34 and the sliding member 50. The elastic member 57 has a beam structure (specifically, a cantilever structure) that protrudes outward from the flange portion 54 of the sliding member 50. One end of the beam structure is fixed to the flange portion 54, and the other end is free. The beam structure protrudes obliquely relative to the axis of the sliding member 50. As a result, as indicated by arrow G in FIG. 16 , the beam structure can elastically deform due to a load acting between the inner wall of the pedal hole 34 and the sliding member 50. Therefore, the beam structure can fill the gap between the inner wall of the pedal hole 34 and the sliding member 50, thereby reducing rattle between the inner wall of the pedal hole 34 and the sliding member 50. Therefore, the sixth embodiment can achieve the same effects as the fifth embodiment.

[0060] Seventh Embodiment A seventh embodiment will be described. As shown in FIGS. 17 and 18 , in the seventh embodiment, the sliding surface SS of the housing 2 that slides against the sliding member 50 is an inclined surface 28. Specifically, the sliding surface SS of the first side wall portion 21 that slides against the first sliding member 51 and the sliding surface SS of the second side wall portion 22 that slides against the second sliding member 52 are both inclined surfaces 28. Here, an imaginary plane VP that passes through the center of the pedal arm 3 and is perpendicular to the rotation axis CL is defined. The inclined surface 28 of the first side wall portion 21 and the inclined surface 28 of the second side wall portion 22 are both formed so that the distance from the imaginary plane VP to the imaginary plane VP gradually decreases in the direction in which the pedal arm 3 moves with increasing pedal force. Note that the sliding surface SS of the housing 2 that slides against the sliding member 50 may be an inclined surface 28 from the initial position to the entire pedal stroke position, or a portion of the inclined surface 28 may be an inclined surface 28. This allows for the design of a hysteresis characteristic in which the hysteresis reaction force changes in response to the pedal stroke.

[0061] The graph in FIG. 19 shows an example of the pedal force characteristics of the pedal device 1 of the seventh embodiment. As shown in the graph in FIG. 19, the hysteresis reaction forces H4, H5, and H6 gradually increase with increasing pedal stroke. As described above, the sliding surface SS of the housing 2 is the inclined surface 28, which gradually decreases in distance from the imaginary plane VP in the direction in which the pedal arm 3 moves with increasing pedal force. Therefore, as the pedal stroke increases, the compression coil spring serving as the biasing member 60 gradually contracts, gradually increasing the spring load. As a result, the hysteresis reaction forces H4, H5, and H6 gradually increase with increasing pedal stroke. In this way, by adjusting the inclination angle of the inclined surface 28, it is possible to design a hysteresis characteristic in which the hysteresis reaction force changes with the pedal stroke. Furthermore, by forming the sliding surface SS of the housing 2 as the inclined surface 28, it is possible to increase the distance between the inclined surface 28 and the imaginary plane VP at the initial position of the pedal stroke, thereby reducing the hysteresis reaction force. This allows the pedal stroke to be reliably returned to the initial position.

[0062] In the seventh embodiment described above, a virtual plane VP is defined that passes through the center of the pedal arm 3 and is perpendicular to the rotation axis CL. The sliding surface SS of the housing 2 has at least a portion of an inclined surface 28 that gradually approaches the virtual plane VP in the direction in which the pedal arm 3 moves as the pedal force increases. This allows for a hysteresis characteristic to be designed in which the hysteresis reaction force changes in response to the pedal stroke. Specifically, as the pedal stroke increases, the compression coil spring serving as the biasing member 60 gradually contracts to increase the spring load and gradually increase the hysteresis reaction force. This improves pedal comfort and vehicle operability. Furthermore, by reducing the hysteresis reaction force at the start of pedal arm depression, the pedal stroke can be reliably returned to the initial position. This prevents the sensor 6 from outputting a signal indicating that the pedal stroke is greater than zero when the driver's pedal force is not applied to the pedal pad 31. When forming the inclined surface 28 on the resin housing 2, depending on the shape of the housing 2, it is also possible to form the inclined surface 28 as a draft angle of the mold used during resin injection molding.

[0063] Eighth Embodiment The eighth embodiment will be described. The eighth embodiment is a modification of the seventh embodiment. As shown in FIG. 20 , in the eighth embodiment, the pedal device 1 includes a housing-side component 29 fixed to the housing 2. The biasing member 60 of the hysteresis generating mechanism 5 biases the sliding member 50 toward a sliding surface SS of the housing-side component 29. The sliding member 50 slides against the sliding surface SS of the housing-side component 29. The sliding surface SS of the housing-side component 29 forms an inclined surface 28 that gradually approaches the imaginary plane VP in the direction in which the pedal arm 3 moves as the pedal force increases. That is, in the eighth embodiment, the inclined surface 28 is formed on the housing-side component 29 fixed to the housing 2. This eighth embodiment can also achieve the same effects as the seventh embodiment. Furthermore, in the eighth embodiment, depending on the shape and manufacturing method of the housing 2, it is possible to form the inclined surface 28 on the housing-side component 29 in a direction opposite to the draft angle of the mold used when resin injection molding the housing 2.

[0064] Ninth Embodiment A ninth embodiment will be described. As shown in Figures 21 and 22, in the ninth embodiment, the first side wall portion 21 and the second side wall portion 22 of the housing 2 have grooves 20 at locations facing the sliding member 50 when the pedal arm 3 is in the initial position. The grooves 20 have an opening area larger than that of the sliding member 50 when the pedal arm 3 is in the initial position. Therefore, when the pedal arm 3 is in the initial position, the normal force of the sliding surface SS against the biasing force of the biasing member 60 is zero or close to zero. Note that the grooves 20 may have an opening area larger than that of the sliding member 50 throughout the entire range of states in which the pedal arm 3 has moved slightly in the depression direction from the initial position.

[0065] The graph in Fig. 23 shows an example of the pedal force characteristics of the pedal device 1 of the ninth embodiment. As shown in the graph in Fig. 23, when the pedal arm 3 is in a slightly increased position from the initial position, the hysteresis reaction force is 0 or close to 0, and the pedal force characteristics coincide with the FS characteristics. As the pedal stroke increases from there, the hysteresis reaction forces H7 and H8 become constant values.

[0066] In the ninth embodiment described above, the housing 2 has a groove 20 that does not slide with the sliding member 50 at a location facing the sliding member 50 when the pedal arm 3 is in the initial position. As a result, when the pedal arm 3 is in the initial position, the hysteresis reaction force is zero or close to zero. Therefore, the pedal stroke can be reliably returned to the initial position. This prevents the sensor 6 from outputting a signal indicating that the pedal stroke is greater than zero when the driver's pedal force is not being applied to the pedal pad 31. Incidentally, if liquid such as rainwater gets between the sliding member 50 and the sliding surface SS, the frictional force may increase. In contrast, in the ninth embodiment, the housing 2 has the groove 20, which allows liquid that gets between the sliding member 50 and the sliding surface SS to be discharged into the groove 20. Therefore, an unintended increase in the hysteresis reaction force can be prevented, and stable hysteresis characteristics can be obtained.

[0067] Tenth Embodiment A tenth embodiment will be described. As shown in FIG. 24 , in the tenth embodiment, the sliding member 50 has a sliding end portion 53, a flange portion 54, and a spring installation portion 55, similar to the first embodiment. The flange portion 54 has an outer shape larger than that of the sliding end portion 53 in a direction perpendicular to a direction parallel to the axis of the cylindrical sliding end portion 53 (i.e., the biasing direction of the biasing member 60). Therefore, a step shape ST is formed between the sliding end portion 53 and the flange portion 54. Furthermore, the outer dimension D3 of the sliding end portion 53 and the outer dimension D4 of the spring installation portion 55 are different. Alternatively, the shape of the sliding end portion 53 and the shape of the spring installation portion 55 may be different.

[0068] 24 and 25 show how the pedal arm 3, to which the reaction force generating mechanism 4 is attached, is assembled to the housing 2 during the manufacture of the pedal device 1. At this time, the pedal arm 3, to which the reaction force generating mechanism 4 is attached, can be easily assembled to the housing 2 by, for example, gripping the step shape ST of the sliding member 50 with a chuck 7.

[0069] Furthermore, in the tenth embodiment, the sliding end portion 53 and the spring installation portion 55 have different dimensions or shapes, which prevents the compression coil spring serving as the biasing member 60 from being erroneously assembled to the sliding end portion 53 during manufacturing. Therefore, the compression coil spring and the spring installation portion 55 can be assembled correctly.

[0070] Eleventh Embodiment An eleventh embodiment will be described. As shown in FIG. 26 , in the eleventh embodiment, the sliding member 50 has a protrusion 59 that protrudes from the spring mounting portion 55 on the side opposite the sliding end portion 53. The protrusion 59 functions to limit the contraction of the compression coil spring. As shown in FIG. 27 , when the hysteresis generating mechanism 5 is assembled in the pedal hole 34 during the manufacture of the pedal device 1, a compression coil spring may be disposed between two sliding members 50, and the two sliding members 50 may be brought closer to each other to contract the compression coil spring. In this case, the protrusion 59 of the first sliding member 51 and the protrusion 59 of the second sliding member 52 come into contact with each other, thereby preventing the coil wires of the compression coil springs from coming into close contact with each other due to an excess of allowable stress.

[0071] (Twelfth Embodiment) A twelfth embodiment will be described. As shown in Fig. 28 , in the twelfth embodiment, the surface 541 of the flange portion 54 of the sliding member 50 facing the inner wall of the pedal hole 34 has an arc-shaped curved surface when viewed in a cross section parallel to the biasing direction of the biasing member 60 (i.e., when viewed in a cross section parallel to the coil axis Ax of the compression coil spring). This makes it possible to prevent unintended changes in the frictional force between the inner wall of the pedal hole 34 and the flange portion 54, even when the sliding member 50 is tilted with respect to the coil axis Ax of the compression coil spring, as shown in Fig. 29 . This prevents unintended changes in the hysteresis reaction force, thereby achieving stable hysteresis characteristics.

[0072] 13th Embodiment A 13th embodiment will be described. As shown in Fig. 30 , in the 13th embodiment, the hysteresis generating mechanism 5 includes a vibration damping member 63 inside the coil wire of the compression coil spring serving as the biasing member 60. The vibration damping member 63 is formed, for example, from a cylindrical rubber material and is capable of damping vibration of the compression coil spring. In the 13th embodiment, the vibration damping member 63 damps vibration of the compression coil spring, thereby preventing abnormal noise from being generated by the hysteresis generating mechanism 5.

[0073] Fourteenth Embodiment A fourteenth embodiment will now be described. As shown in Fig. 31 , in the fourteenth embodiment, the hysteresis generating mechanism 5 includes a vibration damping member 64 on the outer side of the coil wire of the compression coil spring serving as the biasing member 60. The vibration damping member 64 is formed, for example, from a cylindrical rubber material and is capable of damping vibration of the compression coil spring. The fourteenth embodiment can also achieve the same effects as the thirteenth embodiment.

[0074] Fifteenth Embodiment A fifteenth embodiment will be described. As shown in FIG. 32 , in the fifteenth embodiment, a low-rigidity portion 70 having low rigidity is provided in a portion of the sliding member 50 of the hysteresis generating mechanism 5. In FIG. 32 , the low-rigidity portion 70 is indicated by a thick solid line. The low-rigidity portion 70 is configured to deform or break before the pedal arm 3 or the housing 2 when a certain level of stress is applied thereto. Possible cases in which a certain level of stress is applied to the low-rigidity portion 70 include an unintended increase in the friction force between the sliding surface SS and the sliding member 50, or a foreign object being trapped in the hysteresis generating mechanism 5. In such cases, the low-rigidity portion 70 is deformed or separated by the pedal force applied to the pedal arm 3, thereby enabling the pedal arm 3 to operate and return the pedal arm 3 to its initial position.

[0075] Sixteenth Embodiment A sixteenth embodiment will now be described. As shown in FIG. 33 , in the sixteenth embodiment, a low-rigidity portion 71 with low rigidity is provided in a portion of the pedal arm 3 where the pedal hole 34 is provided. In FIG. 33 , the low-rigidity portion 71 is also indicated by a thick solid line. Specifically, the low-rigidity portion 71 is provided at the connection between the protrusion 36, where the pedal hole 34 is provided, and the pedal arm main body 35. This low-rigidity portion 71 is also configured to deform or break before the pedal arm main body 35 or the housing 2 when a certain level of stress is applied. Examples of situations in which a certain level of stress may be applied to the low-rigidity portion 71 include an unintended increase in the friction force between the sliding surface SS and the sliding member 50, or a foreign object being trapped in the hysteresis generating mechanism 5. In such cases, the low-rigidity portion 71 is deformed or separated by the pedal force applied to the pedal arm 3, thereby enabling the pedal arm 3 to move and return to its initial position.

[0076] 34 and 35 , in the seventeenth embodiment, the hysteresis generating mechanism 5 is provided at a position on the rotation axis CL of the pedal arm 3. For example, the sliding member 50 and the biasing member 60 may be housed inside a pedal hole 34 provided around the shaft 32.

[0077] (Eighteenth Embodiment) An eighteenth embodiment will be described. As shown in Figures 36 and 37 , the pedal device 1 of the eighteenth embodiment includes a pedal-side component 80 that operates together with the pedal arm 3. The pedal-side component 80 is configured to rotate within a predetermined angular range around a rotation axis CL2, which is the axis of a second shaft 81 provided in the housing 2. The reaction force generating mechanism 4 biases the pedal arm 3 toward its initial position via the pedal-side component 80. When the driver's pedal force is transmitted from the pedal arm 3 to the pedal-side component 80, the pedal-side component 80 operates together with the pedal arm 3. A pedal hole 34 is provided in the pedal-side component 80. A sliding member 50 and a biasing member 60 that constitute a hysteresis generating mechanism 5 are provided inside the pedal hole 34.

[0078] As in the eighteenth embodiment described above, the hysteresis generating mechanism 5 may be provided in the pedal side component 80 that operates together with the pedal arm 3 .

[0079] (Other Embodiments) (1) In each of the above embodiments, the pedal device 1 has been described as a brake pedal device used in a brake-by-wire system of a vehicle. However, the pedal device 1 is not limited to this, and may be, for example, an accelerator pedal device used in an accelerator-by-wire system.

[0080] (2) In the above embodiments, the pedal device 1 is described as being of a so-called pendant type in which the pedal pad 31 is disposed below the vehicle relative to the rotation axis CL of the pedal arm 3 when mounted on the vehicle. However, the present invention is not limited to this. For example, the pedal device 1 may be of a so-called organ type in which the pedal pad 31 is disposed above the vehicle relative to the rotation axis CL of the pedal arm 3 when mounted on the vehicle.

[0081] (3) In the first embodiment, the reaction force generating mechanism 4 is described as being composed of three compression coil springs 41, 42, and 43 and three holders 44, 45, and 46. However, the present invention is not limited to this and may be composed of, for example, one or more springs or actuators.

[0082] (4) In the third embodiment, the biasing member 60 and the sliding member 50 are accommodated in the housing hole 26 provided in the housing 2. However, the present invention is not limited to this. The biasing member 60 and the sliding member 50 may be accommodated in the housing hole 26 provided in the housing side component 29.

[0083] (5) In the third embodiment, the sliding member 50 housed in the housing hole 26 is in sliding contact with a portion of the sliding surface SS of the pedal arm 3. However, the present invention is not limited to this configuration, and the sliding member 50 may be configured to slide against a portion of the sliding surface SS of the pedal-side component 80.

[0084] (6) In the fifth and sixth embodiments, the sliding member 50 including the elastic member 56 is provided in the pedal hole 34. However, the present invention is not limited to this, and the sliding member 50 including the elastic member 56 may be provided in the housing holes 26, 27. In this case, the elastic member 56 is provided between the sliding member 50 and the inner walls of the housing holes 26, 27, and is elastically deformable by a load acting between the sliding member 50 and the inner walls of the housing holes 26, 27.

[0085] (7) In the above eighteenth embodiment, the sliding member 50 housed in the pedal hole 34 provided in the pedal-side component 80 is in sliding contact with the sliding surface SS of a part of the housing 2. However, the present invention is not limited to this. For example, the sliding member 50 may be configured to slide against the sliding surface SS of a part of the housing-side component 29.

[0086] The present disclosure is not limited to the above-described embodiments and can be modified as appropriate. Furthermore, the above-described embodiments and portions thereof are not unrelated to each other and can be combined as appropriate unless the combination is clearly impossible. It goes without saying that, in each of the above embodiments, the elements constituting the embodiments are not necessarily essential unless specifically stated as essential or clearly considered essential in principle. Furthermore, in each of the above embodiments, when numerical values ​​such as the number, values, amounts, and ranges of components of the embodiments are mentioned, they are not limited to the specific numbers unless specifically stated as essential or clearly limited to a specific number in principle. Furthermore, in each of the above embodiments, when the shape, positional relationship, etc. of components, etc. are mentioned, they are not limited to the shape, positional relationship, etc., unless specifically stated or limited to a specific shape, positional relationship, etc. in principle.

[0087] (Viewpoints of the Present Disclosure) The above-described present disclosure can be understood from the following viewpoints, for example. [First Aspect] A pedal device mounted on a vehicle, comprising: a housing (2) attached to the vehicle; a pedal arm (3) rotatably supported relative to the housing around a predetermined rotation axis (CL) and operated by a driver to depress; a reaction force generating mechanism (4) that applies a reaction force to the pedal arm in response to a pedal force applied by the driver to the pedal arm; and a hysteresis generating mechanism (5) that is a mechanism independent of the reaction force generating mechanism and generates a hysteresis characteristic in which the reaction force when the pedal is depressed is greater than the reaction force when the pedal is released over a predetermined pedal stroke, wherein the hysteresis generating mechanism has: a sliding member (50) that slides on a sliding surface (SS) of a part of the housing (2), or a housing-side component (29) fixed to the housing, or the pedal arm (3), or a pedal-side component (80) that operates together with the pedal arm; and a biasing member (60) that biases the sliding member toward the sliding surface in a direction parallel to the rotation axis of the pedal arm. [Second Aspect] The pedal device according to the first aspect, further comprising a sensor (6) that detects the pedal stroke. [Third Aspect] The pedal device according to the first or second aspect, wherein the hysteresis generating mechanism is provided on the rotation axis of the pedal arm or at a predetermined distance (D1) from the rotation axis. [Fourth Aspect] The pedal device according to any one of the first to third aspects, wherein the biasing member is a compression coil spring, and a coil axis (Ax) of the compression coil spring is disposed parallel to the rotation axis of the pedal arm.[Fifth Aspect] The pedal device according to any one of the first to fourth aspects, wherein the hysteresis generating mechanism is configured such that the sliding member and the biasing member are provided on the pedal-side component or the pedal arm, and the biasing member biases the sliding member toward the sliding surface of the housing-side component or a part of the housing when the pedal arm is depressed and released; or the sliding member and the biasing member are provided on the housing-side component or the housing, and the biasing member biases the sliding member toward the sliding surface of the pedal-side component or a part of the pedal arm when the pedal arm is depressed and released. [Sixth Aspect] The pedal device according to any one of the first to fifth aspects, wherein the pedal-side component or the pedal arm is provided with a pedal hole portion (34) having openings on one surface facing the pedal arm in a direction parallel to the rotation axis and on the other surface facing the pedal arm, and the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside the pedal hole portion, and the biasing member biases the sliding member toward the sliding surface of the housing-side component or a part of the housing. [Seventh Aspect] The pedal device according to any one of the first to fifth aspects, wherein the pedal-side component or the pedal arm is provided with a pedal hole portion having an opening on one surface facing the pedal arm in a direction parallel to the rotation axis, and the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside the pedal hole portion, and the biasing member biases the sliding member toward the sliding surface of the housing-side component or a part of the housing. [Eighth Aspect] A pedal device according to any one of the first to fifth aspects, wherein the housing-side component or the housing is provided with a housing hole (26, 27) having an opening on the pedal arm side or the pedal-side component side, and the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside the housing hole, and the biasing member biases the sliding member against the sliding surface of the pedal-side component or a part of the pedal arm.[Ninth Aspect] The pedal device according to the sixth or seventh aspect, wherein the pedal hole portion has an attachment / detachment opening (37) that opens in a direction intersecting the rotation axis of the pedal arm, and the biasing member and the sliding member are attachable to and detachable from the pedal hole portion through the attachment / detachment opening. [Tenth Aspect] The pedal device according to any one of the first to ninth aspects, wherein the hysteresis generating mechanism is such that the biasing member and the sliding member are provided inside a pedal hole portion provided in the pedal arm or the pedal-side component, or inside a housing hole portion provided in the housing or the housing-side component, and further includes an elastic member (56, 57) between an inner wall of the pedal hole portion and the sliding member, or between an inner wall of the housing hole portion and the sliding member, the elastic member being elastically deformable by a load acting between the inner wall of the pedal hole portion and the sliding member, or a load acting between the inner wall of the housing hole portion and the sliding member. [Eleventh Aspect] The pedal device according to any one of the first to seventh aspects, wherein, when a virtual plane (VP) is defined that passes through the center of the pedal arm or the pedal-side component and is perpendicular to the rotation axis of the pedal arm, the sliding surface of the housing or the housing-side component that slides against the sliding member has, in at least a portion thereof, an inclined surface (28) that gradually decreases in distance from the virtual plane toward a direction in which the pedal arm moves with an increase in pedal force. [Twelfth Aspect] The pedal device according to any one of the first to seventh aspects, wherein the housing or the housing-side component has a groove portion (20) that does not slide against the sliding member, in a portion that faces the sliding member when no pedal force is applied to the pedal arm. [Thirteenth Aspect] The pedal device according to any one of the first to twelfth aspects, wherein the material of the pedal-side component, the housing-side component, the pedal arm, or the housing that constitutes the sliding surface that slides against the sliding member is different from the material of the sliding member.[14th Aspect] The pedal device according to any one of the first to 13th aspects, wherein the sliding member has a sliding end (53) that slides against the sliding surface, and a flange portion (54) whose outer shape in a direction perpendicular to the biasing direction of the biasing member is larger than that of the sliding end, and a step shape (ST) is formed between the sliding end and the flange portion. [15th Aspect] The pedal device according to any one of the first to 14th aspects, wherein the sliding member has a sliding end (53) that slides against the sliding surface, the flange portion (54) whose outer shape in a direction perpendicular to the biasing direction of the biasing member is larger than that of the sliding end, and a spring installation portion (55) formed on the opposite side of the flange portion from the sliding end, and the sliding end and the spring installation portion have different dimensions or shapes. [16th Aspect] The pedal device according to the 15th aspect, wherein the sliding member has a protrusion (59) that protrudes from the spring installation portion toward the opposite side from the sliding end portion and limits the contraction of the compression coil spring serving as the biasing member. [17th Aspect] The pedal device according to any one of the 14th to 16th aspects, wherein the hysteresis generating mechanism is such that the biasing member and the sliding member are provided inside a pedal hole provided in the pedal arm or the pedal-side component, or inside a housing hole provided in the housing or the housing-side component, and a surface (541) of the flange portion facing an inner wall of the pedal hole or the housing hole has an arc-shaped curved surface in a cross section parallel to the biasing direction of the biasing member. [Eighteenth Aspect] The pedal device according to any one of the first to seventeenth aspects, further comprising a cylindrical vibration suppression member (63, 64) provided on the outside or inside of the coil wire of the compression coil spring serving as the biasing member, for suppressing vibration of the compression coil spring.[19th Aspect] The pedal device according to any one of the first to seventh aspects, wherein the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside a pedal hole portion provided in the pedal arm or the pedal-side component, and further includes a low-rigidity portion (70, 71) having low rigidity, provided on a part of the pedal arm where the pedal hole portion is provided or on a part of the sliding member, and when there is an unintended increase in frictional force between the sliding surface and the sliding member, the low-rigidity portion is deformed or broken by the pedal force applied to the pedal arm, thereby making the pedal arm operable and returning to its initial position. [Twentieth Aspect] A pedal device according to any one of the first to seventh aspects, wherein the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside a pedal hole portion provided in the pedal arm or the pedal-side component, and further includes a low-rigidity portion (70, 71) having low rigidity, provided on a part of the pedal arm where the pedal hole portion is provided or on a part of the sliding member, and when a foreign object is caught in the hysteresis generating mechanism, the low-rigidity portion is deformed or broken by the pedal force applied to the pedal arm, thereby enabling the pedal arm to operate and return to its initial position.

Claims

In a pedal device mounted on a vehicle, a housing (2) attached to the vehicle; a pedal arm (3) supported rotatably about a predetermined rotation axis (CL) relative to the housing and operated by a driver by depressing it; a reaction force generating mechanism (4) that applies a reaction force to the pedal arm in response to the pedal force applied by the driver to the pedal arm; a hysteresis generating mechanism (5) that is a mechanism independent of the reaction force generating mechanism and generates a hysteresis characteristic in which the reaction force when the pedal is depressed is greater than the reaction force when the pedal is released at a predetermined pedal stroke; The hysteresis generating mechanism is a sliding member (50) that slides on a sliding surface (SS) of a part of the housing (2), or a housing-side part (29) fixed to the housing, or the pedal arm (3), or a pedal-side part (80) that moves together with the pedal arm; The pedal device has a biasing member (60) that biases the sliding member toward the sliding surface in a direction parallel to the rotation axis of the pedal arm.

2. The pedal device according to claim 1, further comprising a sensor (6) for detecting the pedal stroke.

3. The pedal device according to claim 1, wherein the hysteresis generating mechanism is provided on the rotation shaft of the pedal arm or at a predetermined distance (D1) from the rotation shaft.

3. The pedal device according to claim 1, wherein the biasing member is a compression coil spring, and a coil axis (Ax) of the compression coil spring is disposed parallel to the rotation axis of the pedal arm. 　 The hysteresis generating mechanism is The sliding member and the biasing member are provided on the pedal-side component or the pedal arm, and the biasing member biases the sliding member toward the sliding surface of the housing-side component or a part of the housing when the pedal arm is depressed and released. Alternatively, the pedal device according to claim 1 or 2, wherein the sliding member and the biasing member are provided on the housing-side component or the housing, and the biasing member biases the sliding member toward the sliding surface of the pedal-side component or a part of the pedal arm when the pedal arm is depressed and released. 　 The pedal-side component or the pedal arm is provided with a pedal hole portion (34) having openings on a surface facing one side in a direction parallel to the rotation axis of the pedal arm and a surface facing the other side, 3. The pedal device according to claim 1, wherein the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside the pedal hole portion, and the biasing member biases the sliding member toward the sliding surface of the housing component or a part of the housing. 　 the pedal-side component or the pedal arm is provided with a pedal hole portion having an opening on one side surface of the pedal arm in a direction parallel to the rotation axis, 3. The pedal device according to claim 1, wherein the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside the pedal hole portion, and the biasing member biases the sliding member toward the sliding surface of the housing component or a part of the housing. 　 The housing-side component or the housing is provided with a housing hole portion (26, 27) having an opening on the pedal arm side or the pedal-side component side, 3. The pedal device according to claim 1, wherein the hysteresis generating mechanism is configured such that the biasing member and the sliding member are provided inside the housing hole, and the biasing member biases the sliding member against the sliding surface of the pedal component or a portion of the pedal arm. 　 The pedal hole portion has an attachment / detachment opening (37) that opens in a direction intersecting the rotation axis of the pedal arm, The pedal device according to claim 6, wherein the biasing member and the sliding member are detachably attached to the pedal hole through the detachment opening. 　 The hysteresis generating mechanism is the biasing member and the sliding member are provided inside a pedal hole provided in the pedal arm or the pedal-side component, or inside a housing hole provided in the housing or the housing-side component, 3. The pedal device according to claim 1, further comprising an elastic member (56, 57) between the inner wall of the pedal hole portion and the sliding member, or between the inner wall of the housing hole portion and the sliding member, the elastic member being elastically deformable by a load acting between the inner wall of the pedal hole portion and the sliding member, or a load acting between the inner wall of the housing hole portion and the sliding member. 　 When a virtual plane (VP) that passes through the center of the pedal arm or the pedal side component and is perpendicular to the rotation axis of the pedal arm is defined, 3. The pedal device according to claim 1, wherein the sliding surface of the housing or the housing-side component that slides against the sliding member has at least a portion that is an inclined surface (28) that gradually becomes closer to the imaginary plane in the direction in which the pedal arm moves as the pedal force increases.

3. The pedal device according to claim 1, wherein the housing or the housing side component has a groove portion (20) that does not slide against the sliding member at a portion facing the sliding member when no pedal force is applied to the pedal arm.

3. The pedal device according to claim 1, wherein the material of the pedal-side component, the housing-side component, the pedal arm, or the housing that constitutes the sliding surface that slides against the sliding member is different from the material of the sliding member.

3. The pedal device according to claim 1, wherein the sliding member has a sliding end portion (53) that slides against the sliding surface, and a flange portion (54) whose outer shape, facing a direction perpendicular to the biasing direction of the biasing member, is larger than that of the sliding end portion, and a step shape (ST) is formed between the sliding end portion and the flange portion.

3. The pedal device according to claim 1, wherein the sliding member has a sliding end portion (53) that slides against the sliding surface, a flange portion (54) whose outer shape in a direction perpendicular to the biasing direction of the biasing member is larger than that of the sliding end portion, and a spring mounting portion (55) formed on the opposite side of the flange portion from the sliding end portion, and the sliding end portion and the spring mounting portion have different dimensions or shapes.

16. The pedal device according to claim 15, wherein the sliding member has a protrusion (59) that protrudes from the spring mounting portion on the opposite side to the sliding end portion and limits the contraction of the compression coil spring serving as the biasing member. 　 the hysteresis generating mechanism is such that the biasing member and the sliding member are provided inside a pedal hole provided in the pedal arm or the pedal-side component, or inside a housing hole provided in the housing or the housing-side component, The pedal device according to claim 14, wherein a surface (541) of the flange portion facing the inner wall of the pedal hole portion or the housing hole portion has an arc-shaped curved surface when viewed in a cross section parallel to the biasing direction of the biasing member.

3. The pedal device according to claim 1, further comprising a cylindrical vibration suppressing member (63, 64) provided on the outside or inside of a coil wire of the compression coil spring serving as the biasing member, for suppressing vibration of the compression coil spring. 　 the hysteresis generating mechanism includes the biasing member and the sliding member provided inside a pedal hole provided in the pedal arm or the pedal-side component, The pedal arm further includes a low-rigidity portion (70, 71) having low rigidity, the low-rigidity portion being provided in a part of the portion (36) of the pedal arm where the pedal hole portion is provided or in a part of the sliding member, 3. The pedal device according to claim 1, wherein, in the event of an unintended increase in frictional force between the sliding surface and the sliding member, the low rigidity portion is deformed or broken by a pedal force applied to the pedal arm, thereby enabling the pedal arm to operate and return to its initial position. 　 the hysteresis generating mechanism includes the biasing member and the sliding member provided inside a pedal hole provided in the pedal arm or the pedal-side component, The pedal arm further includes a low-rigidity portion (70, 71) having low rigidity, the low-rigidity portion being provided in a part of the portion (36) of the pedal arm where the pedal hole portion is provided or in a part of the sliding member, 3. The pedal device according to claim 1, wherein when a foreign object is caught in the hysteresis generating mechanism, the low rigidity portion is deformed or broken by the pedal force applied to the pedal arm, thereby enabling the pedal arm to operate and return to its initial position.

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