JP2018069928A - Reaction force generation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reaction force generation device capable of easily changing reaction force characteristics.SOLUTION: One of a cylinder member 121 and a moving member 13 constitutes an engagement side member having an engagement part 121z that engages a seal member 95 in an axial direction, and the other of the cylinder member 121 and the moving member 13 constitutes a slide side member slidable relative to the seal member 95. The seal member 95 comprises an annular base part 951 forming a gap between the slide side member and the seal member in an initial state, and an annular projection part 952 which projects from the base part 951 toward the slide side member and comes into contact with the slide side member in the initial state. The base part 951 is configured to come into contact with the slide side member when a reaction force pressure is equal to or higher than a predetermined pressure.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a reaction force generator for a vehicle.

  The vehicle braking device is equipped with a mechanism (device) that generates a reaction force with respect to the operation of the brake operation member. The reaction force generating device is provided according to the type of vehicle braking device (booster type, by-wire configuration, etc.), for example, having a contact member that contacts the reaction disk, or having a stroke simulator There is. An example of a vehicle braking device having an abutting member is described in Japanese Patent Application Laid-Open No. 4-215558.

JP-A-4-215558

  However, in the reaction force generating device having the contact member, the shape of the contact member must be changed in order to change the reaction force change characteristic (reaction force characteristic). There is a big restriction from the viewpoint of sex. Further, the processing and replacement of the abutting member is structurally difficult, and there are problems in terms of work efficiency and cost. The reaction force characteristic of the stroke simulator is set by a combination of an urging member (spring or the like) and an elastic member (rubber or the like) disposed in the cylinder. There are restrictions on the degree of freedom in the configuration. As described above, in the conventional reaction force generator, there is a limitation in changing the reaction force characteristics from the viewpoint of structure and cost.

  This invention is made | formed in view of such a situation, and it aims at providing the reaction force generator which can change a reaction force characteristic easily.

  The reaction force generator according to the present invention includes a cylinder member having a hydraulic pressure chamber in which a reaction force pressure is generated in response to an operation of a brake operation member of a vehicle, and the cylinder member in the cylinder member in response to an operation of the brake operation member. A moving member that moves in the axial direction of the member, and a seal member that receives the reaction force pressure and seals between the cylinder member and the moving member. A reaction force generation device that generates a reaction force corresponding to a sliding resistance generated in a seal member, wherein one of the cylinder member and the moving member has an engagement portion that engages the seal member in the axial direction. An engaging side member, and the other of the cylinder member and the moving member constitutes a sliding side member that is slidable relative to the seal member, and the seal member is slid in an initial state. An annular base portion that forms a gap with the side member, and an annular convex portion that projects from the base portion toward the sliding side member and contacts the sliding side member in the initial state, The base is configured to contact the sliding member when the reaction force pressure is equal to or higher than a predetermined pressure.

  According to the present invention, the seal member is provided with a stepped structure (step) by the convex portion, and when the reaction force pressure exceeds a predetermined pressure, the contact area between the slide side member and the seal member (that is, the sliding resistance) is the base. It will be bigger by Thereby, a breakpoint can be provided in the gradient of the reaction force characteristic, which is the relationship between the pressure (reaction force pressure) or the operation amount of the brake operation member and the reaction force. That is, it is possible to change the reaction force characteristic to a characteristic simply by changing the shape of the seal member that has relatively small shape restrictions and is relatively easy to manufacture. According to the present invention, the reaction force characteristic can be easily changed.

It is a lineblock diagram of the brake device for vehicles of a first embodiment. It is a conceptual diagram of the reaction force generator of 1st embodiment. It is a conceptual diagram which shows the deformation | transformation of the sealing member of 1st embodiment. It is explanatory drawing which shows the reaction force characteristic of 1st embodiment. It is a conceptual diagram of the sealing member of 1st embodiment. It is a conceptual diagram of the reaction force generator of 2nd embodiment. It is a conceptual diagram of the sealing member of 3rd embodiment. It is explanatory drawing of the reaction force characteristic of 3rd embodiment. It is a conceptual diagram of the sealing member of 4th embodiment. It is a conceptual diagram of the sealing member of 5th embodiment. It is a conceptual diagram of the modification of the sealing member of 5th embodiment. It is a conceptual diagram of the sealing member of 6th embodiment. It is a conceptual diagram of the sealing member of 7th embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings. Each figure used for explanation is a conceptual diagram, and the shape of each part may not necessarily be exact.

  As shown in FIG. 1, the vehicle braking device according to the present embodiment includes a hydraulic braking force generator BF that generates hydraulic braking force on wheels 5FR, 5FL, 5RR, and 5RL, and a brake that controls the hydraulic braking force generator BF. ECU6.

  As shown in FIG. 1, the hydraulic braking force generator BF includes a master cylinder 1, a reaction force generator 2, a first control valve 22, a second control valve 23, a servo pressure generator 4, and an actuator 53. And wheel cylinders 541 to 544, various sensors 71 to 76, and the like.

  The master cylinder 1 is a part that supplies hydraulic fluid (brake fluid) to the actuator 53 in accordance with the amount of operation of the brake pedal 10, and includes a main cylinder 11, a cover cylinder 12, an input piston 13, a first master piston 14, and a first master piston 14. 2 master pistons 15 are provided. The brake pedal (corresponding to a “brake operation member”) 10 may be any brake operation means that allows the driver to operate the brake.

  The main cylinder 11 is a bottomed, substantially cylindrical housing that is closed at the front and opens to the rear. An inner wall 111 that protrudes in an inward flange shape is provided near the rear of the inner periphery of the main cylinder 11. The center of the inner wall 111 is a through hole 111a that penetrates in the front-rear direction. Further, small-diameter portions 112 (rear) and 113 (front) whose inner diameter is slightly smaller are provided in front of the inner wall 111 inside the main cylinder 11. That is, the small diameter portions 112 and 113 project inwardly from the inner peripheral surface of the main cylinder 11. A first master piston 14 is disposed in the main cylinder 11 so as to be slidable in contact with the small diameter portion 112 and movable in the axial direction. Similarly, the second master piston 15 is disposed so as to be slidable in contact with the small diameter portion 113 and movable in the axial direction.

  The cover cylinder 12 includes a cylindrical (substantially cylindrical) cylinder portion (corresponding to a “cylinder member”) 121, a bellows cylindrical boot 122, and a cup-shaped compression spring 123. The compression spring 123 biases the operation rod 10a backward.

  An input piston (corresponding to a “moving member”) 13 is a piston member that slides in the cover cylinder 12 in response to an operation of the brake pedal 10. The input piston 13 is a member that moves in the front-rear direction (the axial direction of the cylinder part 121) in the cylinder part 121 in accordance with the operation of the brake pedal 10. It can be said that the cylinder portion 121 is a part of the master cylinder 1 or a cylindrical member connected to the master cylinder 1. The input piston 13 is axially slidable and liquid-tightly arranged at the rear part 121 b of the cylinder part 121, and the bottom wall 131 enters the inner peripheral side of the front part 121 a of the cylinder part 121. The bottom wall 131 restricts the rearward movement of the input piston 13. Between the input piston 13 and the cylinder part 121, annular seal members 95 and 96 are arranged. The detailed configuration of the seal member 95 and its periphery will be described later.

  Inside the input piston 13, an operation rod 10 a that is linked to the brake pedal 10 is disposed. When the brake pedal 10 is depressed, the operation rod 10a moves forward while pushing the boot 122 and the compression spring 123 in the axial direction. As the operating rod 10a moves forward, the input piston 13 also moves forward. The input piston 13 and the operation rod 10a constitute an input rod.

  The first master piston 14 is disposed on the inner wall 111 of the main cylinder 11 so as to be slidable in the axial direction. The first master piston 14 is formed integrally with a pressurizing cylinder portion 141, a flange portion 142, and a protruding portion 143 in order from the front side. The pressure cylinder 141 is formed in a substantially cylindrical shape with a bottom having an opening on the front, has a gap with the inner peripheral surface of the main cylinder 11, and is in sliding contact with the small-diameter portion 112. A coil spring-like urging member 144 is disposed in the internal space of the pressure cylinder portion 141 between the second master piston 15. The first master piston 14 is urged rearward by the urging member 144. In other words, the first master piston 14 is urged by the urging member 144 toward the set initial position.

  The flange portion 142 has a larger diameter than the pressure cylinder portion 141 and is in sliding contact with the inner peripheral surface of the main cylinder 11. The protruding portion 143 has a smaller diameter than the flange portion 142 and is disposed so as to slide in a liquid-tight manner in the through hole 111 a of the inner wall portion 111. The rear end of the protruding portion 143 passes through the through hole 111 a and protrudes into the internal space of the cylinder portion 121 and is separated from the inner peripheral surface of the cylinder portion 121. The rear end surface of the protrusion 143 is configured to be separated from the bottom wall 131 of the input piston 13 and the separation distance can be changed.

  Here, the inner surface of the main cylinder 11, the front side (front end surface, inner surface) of the pressure cylinder part 141 of the first master piston 14, and the rear side of the second master piston 15, “the first master chamber 1D "Is sectioned. Further, the rear chamber behind the first master chamber 1D is defined by the inner peripheral surface (inner peripheral portion) of the main cylinder 11, the small-diameter portion 112, the front surface of the inner wall portion 111, and the outer peripheral surface of the first master piston 14. ing. The front end portion and the rear end portion of the flange portion 142 of the first master piston 14 divide the rear chamber into the front and rear, the “second hydraulic chamber 1C” is partitioned on the front side, and the “servo chamber 1A” is on the rear side. It is partitioned. Furthermore, the inner peripheral part of the main cylinder 11, the rear surface of the inner wall part 111, the inner peripheral surface (inner peripheral part) of the front part 121a of the cylinder part 121, the protrusion part 143 (rear end part) of the first master piston 14, and the input A “first hydraulic chamber 1 </ b> B (corresponding to“ hydraulic chamber ”)” is defined by the front end portion of the piston 13.

  The second master piston 15 is disposed on the front side of the first master piston 14 in the main cylinder 11 so as to be in sliding contact with the small diameter portion 113 and movable in the axial direction. The second master piston 15 is integrally formed with a cylindrical pressure cylinder portion 151 having an opening in the front and a bottom wall 152 that closes the rear side of the pressure cylinder portion 151. The bottom wall 152 supports the biasing member 144 between the first master piston 14. A coil spring-like urging member 153 is disposed in the internal space of the pressure cylinder portion 151 between the inner bottom surface 111d of the main cylinder 11 closed. The second master piston 15 is urged rearward by the urging member 153. In other words, the second master piston 15 is biased by the biasing member 153 toward the set initial position. A “second master chamber 1 </ b> E” is defined by the inner peripheral surface of the main cylinder 11, the inner bottom surface 111 d, and the second master piston 15.

  The master cylinder 1 is formed with ports 11a to 11i that allow communication between the inside and the outside. The port 11 a is formed behind the inner wall 111 in the main cylinder 11. The port 11b is formed opposite to the port 11a at the same position in the axial direction as the port 11a. The port 11 a and the port 11 b communicate with each other via an annular space between the inner peripheral surface of the main cylinder 11 and the outer peripheral surface of the cylinder part 121. The port 11a and the port 11b are connected to the pipe 161 and to the reservoir 171 (low pressure source).

  The port 11 b communicates with the first hydraulic chamber 1 </ b> B through a passage 18 formed in the cylinder portion 121 and the input piston 13. The passage 18 is shut off when the input piston 13 moves forward, whereby the first hydraulic chamber 1B and the reservoir 171 are shut off.

  The port 11c is formed behind the inner wall 111 and in front of the port 11a, and allows the first hydraulic chamber 1B and the pipe 162 to communicate with each other. The port 11d is formed in front of the port 11c, and communicates the servo chamber 1A and the pipe 163. The port 11e is formed in front of the port 11d and communicates the second hydraulic chamber 1C and the pipe 164.

  The port 11 f is formed between the seal members 91 and 92 of the small diameter portion 112, and communicates the reservoir 172 and the inside of the main cylinder 11. The port 11 f communicates with the first master chamber 1 </ b> D via a passage 145 formed in the first master piston 14. The passage 145 is formed at a position where the port 11f and the first master chamber 1D are blocked when the first master piston 14 moves forward. The port 11g is formed in front of the port 11f, and connects the first master chamber 1D and the pipe 51.

  The port 11 h is formed between the seal members 93 and 94 of the small diameter portion 113 and communicates the reservoir 173 and the inside of the main cylinder 11. The port 11 h communicates with the second master chamber 1 </ b> E via a passage 154 formed in the pressure cylinder portion 151 of the second master piston 15. The passage 154 is formed at a position where the port 11h and the second master chamber 1E are blocked when the second master piston 15 moves forward. The port 11i is formed in front of the port 11h, and communicates the second master chamber 1E and the pipe 52.

  In addition, a seal member such as an O-ring is appropriately disposed in the main cylinder 11 of the master cylinder 1. For example, the seal members 91 and 92 are disposed in the small-diameter portion 112 and are in liquid-tight contact with the outer peripheral surface of the first master piston 14. Similarly, the seal members 93 and 94 are disposed in the small-diameter portion 113 and are in liquid-tight contact with the outer peripheral surface of the second master piston 15.

  The stroke sensor 71 is a sensor that detects an operation amount (stroke) by which the brake pedal 10 is operated by the driver, and transmits a detection signal to the brake ECU 6. The brake stop switch 72 is a switch that detects whether or not the brake pedal 10 is operated by the driver using a binary signal, and transmits a detection signal to the brake ECU 6.

  The reaction force generation mechanism 2 is a mechanism that generates a reaction force that opposes the operation force when the brake pedal 10 is operated, and mainly includes a stroke simulator 21 and a reaction force generator Z. The stroke simulator 21 is a device that generates reaction force pressure in the first hydraulic chamber 1B and the second hydraulic chamber 1C in response to an operation of the brake pedal 10. The stroke simulator 21 is formed on the rear surface side of the cylinder portion 211, a piston portion 212 slidably disposed in the cylinder portion 211, a compression spring 213 that biases the piston portion 212 rearward, and a piston portion 212. The reaction force hydraulic chamber 214, a seal member 215 that seals between the cylinder portion 211 and the piston portion 212, and an elastic member 216 disposed in front of the piston portion 212 in the cylinder portion 121 are provided. . The reaction force characteristic of the stroke simulator 21 is set by the compression spring 213 and the elastic member 216. The reaction force hydraulic chamber 214 is connected to the second hydraulic chamber 1C via the pipe 164 and the port 11e. The reaction force hydraulic chamber 214 is connected to the first control valve 22 and the second control valve 23 via a pipe 164. The reaction force generator Z will be described later.

  The first control valve 22 is an electromagnetic valve having a structure (normally closed type) that is closed in a non-energized state, and opening / closing thereof is controlled by the brake ECU 6. The pressure sensor 73 is a sensor that detects the fluid pressure (reaction force pressure) of the second fluid pressure chamber 1 </ b> C, the first fluid pressure chamber 1 </ b> B, and the reaction force fluid pressure chamber 214, and is connected to the pipe 164. The second control valve 23 is a solenoid valve having a structure (normally open type) that opens in a non-energized state, and opening and closing of the second control valve 23 is controlled by the brake ECU 6. The first control valve 22 and the second control valve 23 are electromagnetic valves for mode switching, block the flow path with the reservoir 171 in normal brake control, and the first hydraulic pressure chamber 1B and the second hydraulic pressure. The room 1C is communicated.

  The servo pressure generator 4 includes a pressure reducing valve 41, a pressure increasing valve 42, a pressure supply unit 43, and a regulator 44. The pressure reducing valve 41 is a normally open type electromagnetic valve. One side connection port of the pressure reducing valve 41 communicates with a reservoir (low pressure source) 171 through pipes 411 and 161 and ports 11a and 11b. The pressure reducing valve 41 is closed to prevent the hydraulic fluid from flowing out from the first pilot chamber 4D described later. Note that the pipe 411 may be connected to a reservoir 434 described later instead of the reservoir 171.

The pressure increasing valve 42 is a normally closed electromagnetic valve, and opening / closing (passage flow rate) is controlled by the brake ECU 6. One side connection port of the pressure increasing valve 42 is connected to the pipe 421, and the other side connection port of the pressure increasing valve 42 is connected to the pipe 422.
The pressure supply unit 43 is a part that mainly supplies high-pressure hydraulic fluid to the regulator 44. The pressure supply unit 43 includes an accumulator (high pressure source) 431, a hydraulic pump 432, a motor 433, a reservoir 434, and the like.

  The accumulator 431 is a pressure accumulator that accumulates high-pressure hydraulic fluid. The accumulator 431 is connected to the regulator 44 and the hydraulic pump 432 by a pipe 431a. The hydraulic pump 432 is driven by the motor 433 and pumps the hydraulic fluid stored in the reservoir 434 to the accumulator 431. The pressure sensor 75 provided in the pipe 431a detects the accumulator hydraulic pressure of the accumulator 431, and transmits a detection signal to the brake ECU 6. The accumulator hydraulic pressure correlates with the accumulated amount of hydraulic fluid accumulated in the accumulator 431.

  The regulator 44 is a mechanical pressure regulator. For example, the regulator 44 generates a pilot pressure corresponding to the pressure of the accumulator 431 in accordance with the control of the pressure reducing valve 41 and the pressure increasing valve 42. The servo pressure increases or decreases based on the pilot pressure. Examples of the regulator 44 include a ball valve type and a spool valve type. Since the detailed configuration of the regulator 44 is known, the description thereof is omitted. The pressure sensor 74 is a sensor that detects the servo pressure supplied to the servo chamber 1 </ b> A, and is connected to the pipe 163. The pressure sensor 74 transmits a detection signal to the brake ECU 6.

  The actuator 53 is a device that regulates the upstream pressure (master pressure) and supplies it to the downstream (wheel cylinders 541 to 544). The actuator 53 operates under the control of the brake ECU 6. Although not shown, the actuator 53 includes a plurality of solenoid valves, an electric pump, and a reservoir. The actuator 53 can be said to be a device that adjusts the wheel pressure based on the master pressure. For example, the actuator 53 supplies the master pressure to the wheel cylinders 541 to 544 in the pressure increase control, causes the brake fluid in the wheel cylinders 541 to 544 to flow out to the reservoir in the pressure reduction control, and seals the wheel cylinders 541 to 544 in the holding control. To do.

  In addition, the actuator 53 may be a type capable of pressurization control in which wheel pressure is increased by an electric pump and a differential pressure control valve, or may be a type that does not include the differential pressure control valve and cannot perform pressurization control. . In the former type, skid prevention control, automatic pressurization control, and the like are possible. Since the detailed configuration of the actuator 53 is known, the description thereof is omitted.

  The brake ECU 6 is an electronic control unit and includes a CPU, a memory, and the like. The brake ECU 6 is connected to various sensors 71 to 76 in order to control the electromagnetic valves 22, 23, 41, 42, the motor 433, and the like. The brake ECU 6 sets a target servo pressure according to the stroke (operation amount) of the brake pedal 10, and controls the pressure increase for the solenoid valves 41 and 42 so that the actual servo pressure approaches the target servo pressure. The decompression control and the holding control are executed. The brake ECU 6 controls the actuator 53 according to ABS control or the like. A wheel speed sensor 76 is provided for each of the wheels 5FR to 5RL.

(Reaction force generator)
Here, the reaction force generator Z will be described. The reaction force generator Z according to the first embodiment includes a cylinder part 121, an input piston 13, and a seal member 95. The seal member 95 is an annular elastic member that receives reaction force pressure and seals between the cylinder portion 121 and the input piston 13. As shown in FIG. 2, the cylinder part 121 has an engaging part 121z that engages the seal member 95 in the front-rear direction (axial direction). The engaging part 121z is an annular groove provided in the inner peripheral part of the cylinder part 121. The seal member 95 is disposed in the engagement portion 121z so as to engage with the cylinder portion 121 in the front-rear direction. The engagement part 121z restricts the movement of the seal member 95 in the front-rear direction.

In this arrangement, the input piston 13 is slidable (movable) relative to the seal member 95. That is, in this configuration, the input piston 13 is a sliding member, and the cylinder part 121 is an engaging member. In addition, when the site | part (for example, annular groove) equivalent to the engaging part 121z is provided in the outer peripheral part of the input piston 13 instead of the cylinder part 121, the input piston 13 comprises an engagement side member. Further, in this case, the cylinder portion 121 constitutes a sliding side member that can slide relative to the seal member 95. Thus, the engaging part 121z is formed in one of the cylinder part 121 and the input piston 13, and one of the cylinder part 121 and the input piston 13 constitutes an engaging side member, and the cylinder part 121 and the input piston 13 The other of the pistons 13 constitutes a sliding side member.
The reaction force generator Z includes a cylinder part 121 having a hydraulic chamber 1B in which a reaction force pressure is generated according to the operation of the brake pedal 10 of the vehicle, and the cylinder part 121 inside the cylinder part 121 according to the operation of the brake pedal 10. And an input piston 13 that moves in the axial direction, and a seal member 95 that receives the reaction force pressure and seals between the cylinder portion 121 and the input piston 13. 95 is a device that generates a reaction force corresponding to the sliding resistance generated in 95.

  The seal member 95 is an annular elastic member, and is formed so that a cross section cut along a plane including the central axis of the cylinder portion 121 (hereinafter referred to as “axial cross section”) has a convex shape having a step. . In other words, the seal member 95 has a stepped shape at a portion (tip portion) closer to the sliding side member. Specifically, the seal member 95 includes an annular base portion 951 and an annular convex portion 952 protruding from the inner peripheral surface of the base portion 951 toward the input piston 13 (in the radial direction of the seal member 95). The axial width (length) of the convex portion 952 is smaller than the axial width of the base portion 951. Therefore, a step is formed by the base portion 951 and the convex portion 952. In the first embodiment, the axial section of the base 951 has a quadrangular shape (rectangular shape in the drawing), and the axial section of the convex portion 952 also has a quadrangular shape (rectangular shape in the drawing).

  The base 951 forms a gap with the input piston 13 in the initial state. That is, the inner peripheral surface of the base 951 (the peripheral surface close to the sliding member) is not in contact with the input piston 13 in the initial state. The initial state is a state where the brake pedal 10 is not operated (a state where the input piston 13 is not moving) or a state where the reaction force pressure is atmospheric pressure. It can be said that the initial state is a state when the vehicle braking device is shipped. The outer peripheral surface of the base portion 951 is in contact with the inner peripheral surface of the cylinder portion 121 (the bottom surface of the engaging portion 121z) over the entire periphery.

  The convex portion 952 is formed at the center in the axial direction of the inner peripheral surface of the base portion 951. The convex portion 952 is in contact with the input piston 13 in the initial state. The inner peripheral surface (protruding end surface) of the convex portion 952 is in contact with the outer peripheral surface of the input piston 13 over the entire periphery. In order to ensure the sealing performance in the initial state, the base portion 951 is in contact with the cylinder portion 121 and the convex portion 952 is in contact with the input piston 13. It can be said that the inner peripheral surface of the seal member 95 is a sliding surface that generates a sliding resistance with the input piston 13.

  Here, the base 951 is configured to come into contact with the input piston 13 when the reaction force pressure exceeds a predetermined pressure. The engaging portion 121z communicates with the first hydraulic chamber 1B through a slight gap between the cylinder portion 121 and the input piston 13. That is, a reaction force pressure is applied to the seal member 95 from the front (one side in the axial direction of the cylinder portion 121). The seal member 95 is elastically deformed as the reaction force pressure increases.

  Specifically, as shown in FIG. 3, when the reaction force pressure increases from the initial state, the base 951 is compressed in the axial direction, the radial width of the base 951 increases, and the inner peripheral surface (exposed surface) of the base 951 Or a space forming surface) approaches the input piston 13. Then, when the reaction force pressure reaches a predetermined pressure, the inner peripheral surface of the base 951 comes into contact with the input piston 13. When the reaction force pressure decreases, the base portion 951 attempts to return to the original shape, and when the reaction force pressure becomes less than a predetermined pressure, the base portion 951 moves away from the input piston 13. The predetermined pressure corresponds to the value of the reaction force pressure generated when the brake pedal 10 reaches a predetermined stroke (stroke within the use stroke range). That is, it can be said that the base 951 contacts the input piston 13 when the stroke becomes equal to or greater than the predetermined stroke.

  The inner peripheral surface of the convex portion 952 always functions as a seal surface (sliding surface), and the inner peripheral surface of the base portion 951 functions as a seal surface (sliding surface) when the reaction force pressure is equal to or higher than a predetermined pressure. That is, the contact area between the seal member 95 and the input piston 13 (hereinafter also simply referred to as “contact area”) increases at a stretch when the reaction force pressure exceeds a predetermined pressure. When the reaction force pressure is less than the predetermined pressure with respect to the movement of the input piston 13, sliding resistance is generated on the inner peripheral surface of the convex portion 952, and when the reaction force pressure is greater than or equal to the predetermined pressure, Sliding resistance is generated on the peripheral surface and the inner peripheral surface of the base 951. The sliding resistance generated with respect to the movement of the input piston 13 becomes a reaction force against the operation of the brake pedal 10. That is, the reaction force generator Z generates a reaction force corresponding to the sliding resistance generated in the seal member 95. The reaction force against the movement of the input piston 13, that is, the reaction force against the operation of the brake pedal 10 is mainly “a force by which the reaction force pressure presses the input piston 13” and “a force due to the sliding resistance of the input piston 13”. Determined by the sum of However, the force due to the sliding resistance increases in proportion to the increase of the reaction force pressure when the contact area is constant.

  In the first embodiment, the relationship between the reaction force and the pressure (reaction force pressure received by the seal member 95) (hereinafter referred to as “reaction force characteristic”) changes the gradient (inclination) at a predetermined pressure as shown in FIG. The relationship has a break point. It can be said that the seal member 95 is a member having a break point (for example, an inflection point) in the reaction force characteristic. In the first embodiment, the reaction force due to the sliding resistance of the input piston 13 is changed to change the overall reaction force characteristics.

  The design of the reaction force characteristics of the seal member 95 will be described with reference to FIGS. In the description, the horizontal axis is the reaction force, and the vertical axis is the pressure (see FIG. 4). The length A, that is, the length of the convex portion 952 in the axial direction is an element that determines the gradient before the break point, and the gradient before the break point becomes smaller as the length A becomes larger. The length A is related to the size of the contact area in the initial state. The length B, that is, the length of the base 951 in the axial direction is an element that determines the gradient after the break point, and the gradient after the break point becomes smaller as the length B becomes larger. The length B is related to the contact area at a predetermined pressure or higher. The length C, that is, the radial length (projection length) of the convex portion 952 is an element that determines the position (predetermined pressure) of the break point, and the greater the position, the higher the position of the break point. The angle D, that is, the angle formed between the end face in the axial direction of the convex portion 952 and the inner peripheral surface of the base portion 951 is an element that determines the relationship before the break point, and the relationship becomes rounder as it is larger than 90 °. Due to the angle D, the inner peripheral surface of the seal member 95 becomes a discontinuous surface.

  According to the present embodiment, a step structure (step) is provided on the seal member 95 by the convex portion 952, and when the reaction force pressure exceeds a predetermined pressure, the contact area between the input piston 13 and the seal member 95 is the amount of the base 951. Only get bigger. With this stepped structure, the contact area changes abruptly with a predetermined pressure as a boundary, so that a break point can be provided in the gradient of the reaction force characteristic that is the relationship between the pressure and the reaction force. That is, it is possible to change the characteristic to the reaction force characteristic only by changing the shape of the seal member 95. According to this embodiment, the reaction force characteristic can be easily changed.

  Further, according to the present embodiment, the shape restriction of the seal member 95 from the viewpoint of durability is relatively small, and the degree of freedom in changing the reaction force characteristics can be improved. Moreover, the manufacture of the seal member is relatively easy. According to this embodiment, for example, the design change (adjustment) of the brake feeling is also facilitated. Further, since the reaction force characteristic can be adjusted by the seal member 95, the reaction force characteristic of the entire vehicle set by the stroke simulator 21 can be easily changed. From the viewpoint of improving durability, it is possible to make the elastic member 216 of the stroke simulator 21 simple or not.

  Further, for example, if this embodiment is applied to a seal member of a braking device for a vehicle having a vacuum booster, a reaction force characteristic can be obtained by the seal member. Therefore, it is necessary to obtain a reaction force characteristic by the structure of the reaction disk and the contact member. Disappear. Thereby, a contact member can be made into a simple shape (for example, flat plate shape), or can be eliminated, and durability of a reaction disk can be improved. Regardless of the type of booster or the like, the seal member 95 according to the present embodiment is applied to a slide (reaction force pressure) that increases as the amount of operation of the brake pedal increases, and is caused by the movement of the sliding side member. Any seal member whose dynamic resistance affects the magnitude of the reaction force of the brake pedal may be used.

<Second embodiment>
The reaction force generator Z of the second embodiment is the stroke simulator 21 of the first embodiment in which the shape of the seal member 215 is changed. Here, differences between the second embodiment and the first embodiment will be described, and other descriptions will be omitted. In the description of the second embodiment, reference can be made to the description of the first embodiment and the drawings.

  The seal member 215 of the stroke simulator 21 of the second embodiment has a stepped structure as in the first embodiment. Specifically, as shown in FIG. 6, the seal member 215 includes an annular base portion 215 a, and an annular convex portion 215 b that protrudes from the outer peripheral surface of the base portion 215 a to the cylinder portion 211 side (the radially outer side of the seal member 215). It is equipped with. The base portion 215a forms a gap with the cylinder portion (corresponding to the “cylinder member”) 211 when the reaction force pressure is lower than a predetermined value, and is deformed when the reaction force pressure is equal to or higher than the predetermined pressure. The cylinder portion 211 is configured to abut. The convex part 215b is in contact with the cylinder part 211 in the initial state. The difference between the seal member 215 and the seal member 95 is only the position of the convex portion, and the other configurations can refer to the description of the first embodiment and the drawings.

  The piston part (corresponding to a “moving member”) 212 has an engaging part 212a for engaging the seal member 215 in the axial direction. The engaging part 212a is an annular groove as in the first embodiment. The seal member 215 is disposed in the engaging portion 212a. When the piston part 212 moves with respect to the cylinder part 211, the seal member 215 also moves. That is, in the second embodiment, the piston part 212 constitutes an engagement side member, and the cylinder part 211 constitutes a sliding side member that can slide relative to the seal member 215. The convex part 215b is formed in the surrounding surface near the sliding side member of the base part 215a like 1st embodiment. The seal member 215 receives reaction force pressure from behind via a slight gap between the cylinder portion 211 and the piston portion 212.

  According to the second embodiment, the sliding resistance of the piston portion 212 of the stroke simulator 21 changes abruptly at a certain pressure. The sudden change of the sliding resistance (contact area) generated in the seal member 215 causes a break point in the relationship between the moving distance (value related to the stroke) of the piston part 212 and the reaction force pressure. In other words, in the second embodiment, the change gradient with respect to the stroke of the reaction force pressure is changed and the change gradient with respect to the stroke of the reaction force is changed by a sudden change in the sliding resistance. In the second embodiment, a break point is provided in the reaction force characteristic that is the relationship between the reaction force and the stroke. The reaction force characteristic of the second embodiment corresponds to, for example, the reaction force pressure in FIG. 4 replaced with a stroke. According to the second embodiment, the same effect as the first embodiment is exhibited.

  Further, if the reaction force pressure becomes a predetermined pressure during a predetermined stroke, the base 215a has a sliding side member (here, the cylinder portion 211) when the stroke (operation amount) is equal to or greater than the predetermined stroke (predetermined operation amount). It can be said that it is comprised so that it may contact | abut. The predetermined stroke is a value within the use stroke range. In the second embodiment, the seal member 95 may be a general seal member, but may have a stepped structure as in the first embodiment.

<Third embodiment>
Hereinafter, modified examples of the sealing member having the stepped structure according to the first embodiment and the second embodiment will be described with reference to axial sectional views.
First, as shown in FIG. 7, the seal member 95A of the third embodiment has a multi-stepped structure. Specifically, the seal member 95A includes a base portion 95A1, a first convex portion 95A2, and a second convex portion 95A3. The first convex portion 95A2 and the second convex portion 95A3 are adjacent to and in contact with each other. The protruding length of the first convex portion 95A2 from the base portion 95A1 is larger than the protruding length of the second convex portion 95A3 from the base portion 95A1. The first convex portion 95A2 contacts the sliding side member in the initial state, and the second convex portion 95A3 and the base portion 95A1 form a gap with the sliding side member in the initial state. The second convex portion 95A3 contacts the sliding member when the reaction force pressure is equal to or higher than the first predetermined pressure, and the base portion 95A1 is when the reaction force pressure is equal to or higher than the second predetermined pressure higher than the first predetermined pressure. It is comprised so that it may contact | abut to a sliding side member. Thereby, as shown in FIG. 8, a plurality of break points can be provided in the reaction force characteristic, and a finer change is possible.

<Fourth embodiment>
As shown in FIG. 9, the seal member 95B according to the fourth embodiment includes a base portion 95B1 and two convex portions 95B2. The two convex portions 95B2 are spaced apart from each other and protrude from the base portion 95B1. The tip portion of the seal member 95B is formed in a concave shape. The two convex portions 95B2 are in contact with the sliding member in the initial state, and the base portion 95B1 forms a gap with the sliding member in the initial state. The base portion 95B1 contacts the sliding side member when the reaction force pressure is equal to or higher than a predetermined pressure. This also exhibits the same effect as the first embodiment.

<Fifth embodiment>
As shown in FIG. 10, the seal member 95C of the fifth embodiment includes a base portion 95C1 and a convex portion 95C2. The convex portion 95C2 is formed so that the shape in the axial cross section becomes a convex arc shape (for example, a semicircular shape) in which the axial width decreases as the sliding side member is closer. In other words, the shape of the tip portion of the convex portion 95C2 in the axial cross section is a curved shape that swells toward the sliding member. The convex portion 95C2 is in contact with the sliding member in the initial state, and the tip of the convex portion 95C2 is pressed by the sliding member in the initial state, and is deformed into a flat shape in the axial cross section. The base 95C1 is separated from the sliding member when the reaction force pressure is less than a predetermined pressure, and contacts the sliding member when the reaction force pressure is equal to or greater than the predetermined pressure. According to this, until the reaction force pressure reaches a predetermined pressure, the contact area between the convex portion 95C2 and the sliding side member gradually increases as the reaction force pressure increases, and the reaction force characteristics are before the break point. The gradient is rounded. This also exhibits the same effect as the first embodiment. From the viewpoint of durability of the seal member 95, it is preferable that at least the tip portion of the convex portion 95C2 has a convex arc shape. As shown in FIG. 11, the convex portion 95C2 may have a convex arc shape only at the distal end portion, and the base end portion may have a quadrangular shape.

<Sixth embodiment>
As shown in FIG. 12, the sealing member 95D of the sixth embodiment includes a base portion 95D1 and a convex portion 95D2. The shape of the convex portion 95D2 in the axial section is a trapezoidal shape in which the axial width decreases as the sliding side member is closer. This corresponds to the angle D of the first embodiment larger than 90 °. This also exhibits the same effect as the first embodiment. Further, the trapezoidal side surface of the convex portion 95D2 may have a curved shape, for example, a convex arc shape (a shape that swells in an arc shape) or a concave arc shape (a shape that is recessed in an arc shape). In addition, the shape of the convex portion 95D2 may be a polygon such as a triangle, a pentagon, or a hexagon that has a smaller axial width as it is closer to the sliding member. The relationship between the distance from the sliding member and the axial width in the convex portion 95D2 may be linear, curved, stepped, or a combination thereof.

<Seventh embodiment>
In the first to sixth embodiments, the shape of the base in the axial cross section may be rounded. For example, as shown in FIG. 13, the seal member 95D includes a base portion 95D1 and a convex portion 95D2. In the cross section in the axial direction, the shape of the base portion 95D1 is a circular shape, and the shape of the convex portion 95D2 is a convex arc shape. This also exhibits the same effect as the first embodiment. The shape of the base in the axial cross section may be a polygonal shape. Further, the corner of the base of the polygonal shape may be a curved surface.

(Other)
The present invention is not limited to the above embodiment. For example, you may apply the sealing member (for example, sealing member 95) of this invention with respect to a some sealing member. In this case, for each reaction force characteristic, each seal member may be designed so that there is one break point, or each seal member may be designed so that a plurality of break points are generated. The effect similar to 3rd embodiment is exhibited by setting the predetermined pressure of each seal member to a different value so that a plurality of break points may occur. Furthermore, in this case, it is not necessary to form one seal member in a multi-stage shape, and manufacture of the seal member is easier than in the third embodiment. Further, the master cylinder 1 may be provided with a spool-type regulator therein as described in, for example, Japanese Patent Application Laid-Open No. 2009-241705.

  The first to seventh embodiments may be combined with each other. In the first to seventh embodiments, the engagement side member and the sliding side member may be opposite to each other. That is, the formation positions of the engaging portions 121z and 212a may be on the cylinder side (for example, the housing side) or on the moving member (for example, the piston) side. The convex part should just protrude toward the sliding side member from the base. In the above embodiment, “predetermined pressure” can be replaced with “predetermined stroke”. 2, 3, 5 to 7, and 9 to 13 are conceptual diagrams illustrating an axial section (partial section).

DESCRIPTION OF SYMBOLS 10 ... Brake pedal (brake operation member), 1B ... 1st hydraulic pressure chamber (hydraulic pressure chamber), 121, 211 ... Cylinder part (cylinder member), 13 ... Input piston (moving member), 212 ... Piston part (moving member) ), 95, 215... Sealing member, 951, 215a, base, 952, 215b, convex, 21 ... stroke simulator, Z ... reaction force generator.

Claims (4)

A cylinder member having a hydraulic chamber in which a reaction force pressure is generated in response to an operation of a brake operation member of the vehicle;
A moving member that moves in the axial direction of the cylinder member in the cylinder member in response to an operation of the brake operating member;
A seal member that receives the reaction force pressure and seals between the cylinder member and the moving member;
A reaction force generator that generates a reaction force corresponding to the sliding resistance generated in the seal member with respect to the operation of the brake operation member,
One of the cylinder member and the moving member constitutes an engagement side member having an engagement portion for engaging the seal member in the axial direction,
The other of the cylinder member and the moving member constitutes a sliding member that can slide relative to the seal member,
The sealing member is
An annular base that forms a gap with the sliding member in the initial state;
An annular convex portion that protrudes from the base portion toward the sliding side member and contacts the sliding side member in the initial state;
With
The base is a reaction force generator configured to contact the sliding member when the reaction pressure is equal to or higher than a predetermined pressure.   The reaction force generator according to claim 1, wherein the convex portion is formed in a convex arc shape in which the width in the axial direction decreases as the sliding side member is closer. The cylinder member is a cylindrical member connected to a part of the master cylinder or the master cylinder,
The reaction force generation device according to claim 1, wherein the moving member is an input piston.   The reaction force generator according to claim 1, wherein the reaction force generator is a stroke simulator.

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