JP2012214090A - Electric braking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric braking device in which a piston is easily assembled into a cylinder, and which allows the cylinder length to be shortened with the number of parts less than conventional ones.SOLUTION: The electric braking device includes: a cylinder part incorporating advanceable/retractable piston; a motor for driving the piston; and a driving force transmission mechanism for transmitting the driving force of the motor to the piston, and generates brake liquid pressure by driving the advancement of the piston by the driving force of the motor. An end of the cylinder part, on an opposite side opposite from the side where the driving force transmission mechanism is disposed, is formed to be openable, and the end on the opposite side is closed by a lid member, and a restriction means is provided between the lid member and the piston such that the driving position of the piston in the cylinder part falls in a predetermined range.

Description

  The present invention relates to an electric brake device, and more particularly to an electric brake device that generates a brake fluid pressure by driving a piston forward by a motor braking force.

  There is known a vehicular brake device including a master cylinder to which an operator's brake operation is input and a slave cylinder as an electric brake device that generates a brake fluid pressure based on an electric signal corresponding to the brake operation. (For example, refer to Patent Document 1).

  In the slave cylinder of this vehicle brake device, when the motor is driven, the piston moves forward via a gear mechanism or the like, so that brake fluid pressure is generated in a fluid pressure chamber formed in front of the piston. It is output to the liquid path through the port.

JP 2008-143419 A

  However, in the slave cylinder described in Patent Document 1, it is necessary to insert and assemble the piston body only from one end side of the cylinder body when assembling the piston, and the assembling property of the piston into the cylinder deteriorates. There is. Moreover, in order to shorten the cylinder length, a guide structure having a large number of parts may be required.

  The present invention has been made in view of the above problems, and an object of the present invention is to make it easy to assemble a piston into the cylinder and to reduce the cylinder length with a smaller number of parts than in the past. To provide an apparatus.

  The invention according to claim 1 includes a cylinder portion including a piston capable of moving back and forth, a motor for driving the piston, a driving force transmission mechanism for transmitting a driving force of the motor to the piston, An electric brake device that generates a brake hydraulic pressure by driving the piston forward by a driving force of the motor, wherein the cylinder portion is an end portion opposite to a side where the driving force transmission mechanism is disposed. Is formed between the lid member and the piston so that the opposite end is closed by the lid member and the drive position of the piston within the cylinder portion is within a predetermined range. The present invention relates to an electric brake device provided with a regulating means.

  According to this invention, since the restricting means is provided between the lid member that closes the opening of the cylinder portion and the piston, there is no need for a receding prevention pin or the like that is provided at the rear of the piston, which has been conventionally used. It can be configured. Further, by adopting a plunger type cylinder, the structure of the piston can be simplified, and the cylinder length can be shortened with a smaller number of parts. Further, since the lid member and the restricting means can be fixed, the structure of the restricting means can be simplified, and the assembling of the restricting means is facilitated.

  The invention according to claim 2 relates to an electric brake device in which the lid member and the regulating means are formed separately, and the regulating means is sandwiched and fixed between the lid member and the cylinder portion. .

  According to this invention, when the lid member is fixed to the cylinder portion, the restricting means is also fixed, so that the manufacturing process can be simplified and can be easily assembled. Further, the restricting means can be fixed to the cylinder portion together with the lid member more firmly.

  According to a third aspect of the present invention, there is provided a cylinder portion including a piston capable of moving back and forth, a motor for driving the piston, and a driving force transmission mechanism for transmitting a driving force of the motor to the piston. And an electric brake device that generates a brake fluid pressure by driving the piston forward by a driving force of the motor, wherein the cylinder portion is on a side opposite to the side on which the driving force transmission mechanism is disposed. The opposite end is closed by a lid member, and the inner diameter of the opposite end is larger than the end on the side where the driving force transmission mechanism is disposed. The present invention relates to an electric brake device in which a step portion is formed on an inner wall of the cylinder portion so as to be large, and the cylinder portion is provided with a seal member for preventing leakage of brake fluid in the cylinder portion. .

  According to the present invention, it is not necessary to use a receding prevention pin or the like that is provided behind the piston that has been conventionally used, and a plunger-type cylinder can be configured. And since the structure of a piston becomes a simple structure, while being able to shorten cylinder length, the number of parts can also be reduced. Further, by providing the seal member in the cylinder portion, it is possible to prevent the seal member from moving due to the piston movement, and to reduce wear of the seal member. Moreover, a sealing member having a smaller number of parts than conventional ones can be used.

  ADVANTAGE OF THE INVENTION According to this invention, while making the assembly | attachment property of the piston inside a cylinder easy, the electric brake device which enabled shortening of cylinder length with the number of parts smaller than before can be provided.

It is a figure showing the arrangement composition in vehicles of the brake system for vehicles to which the electric brake equipment concerning one embodiment of the present invention was applied. 1 is a schematic configuration diagram of a vehicle brake system. It is a side view of a motor cylinder device. It is a disassembled perspective view of a motor cylinder apparatus. It is a disassembled perspective view of a driving force transmission part. It is the perspective view seen from the slanting lower part of the motor cylinder device. It is a schematic block diagram which shows the example of a change of an electric brake device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
FIG. 1 is a diagram illustrating an arrangement configuration in a vehicle of a vehicle brake system to which an electric brake device according to an embodiment of the present invention is applied. Note that the front, rear, left and right directions of the vehicle V are indicated by arrows in FIG.

  The vehicle brake system 10 of the present embodiment transmits a hydraulic signal to a by-wire type brake system that transmits an electric signal to operate the brake for normal use and a fail-safe type for use. It is configured with both of the traditional hydraulic brake systems that actuate the brakes.

  As shown in FIG. 1, the vehicle brake system 10 includes an input device 14 to which an operator (driver) brake operation is input, and an electric motor that generates brake fluid pressure based on at least an electric signal corresponding to the brake operation. A motor cylinder device 16 as a brake device, and a vehicle stability assist device 18 (hereinafter referred to as a VSA device) as a vehicle behavior stabilization device that assists in stabilizing the behavior of the vehicle based on the brake fluid pressure generated by the motor cylinder device 16 18, VSA (registered trademark).

  The motor cylinder device 16 may be configured to generate the brake fluid pressure based not only on an electric signal corresponding to a driver's brake operation but also on an electric signal corresponding to another physical quantity. The electrical signal corresponding to the other physical quantity is, for example, an ECU (Electronic Control Unit) that uses a sensor or the like to determine the situation around the vehicle V without relying on the driver's brake operation, as in an automatic brake system. A signal for avoiding a collision of the vehicle V and the like.

  Here, the input device 14 is applied to a right-hand drive vehicle, and is fixed to the right side of the dashboard 2 in the vehicle width direction via a bolt or the like. The input device 14 may be applied to a left-hand drive vehicle. The motor cylinder device 16 is disposed, for example, on the left side in the vehicle width direction opposite to the input device, and is attached to the vehicle body 1 such as the left side frame via a mounting bracket (not shown). The VSA device 18 suppresses, for example, an ABS (anti-lock braking system) function for preventing wheel lock during braking, a TCS (traction control system) function for preventing wheel slipping during acceleration, and a side slip during turning. For example, it is attached to the vehicle body via a bracket at the right front end in the vehicle width direction. Instead of the VSA device 18, an ABS device having only an ABS function for preventing wheel lock during braking may be connected. Detailed configurations of the input device 14, the motor cylinder device 16, and the VSA device 18 will be described later.

  These input device 14, motor cylinder device 16, and VSA device 18 are provided in a structure mounting chamber R in which a structure 3 such as an engine or a traveling motor provided in front of the dashboard 2 of the vehicle V is mounted. They are separated from each other via the piping tubes 22a to 22f. The vehicle brake system 10 can be applied to any of front-wheel drive vehicles, rear-wheel drive vehicles, and four-wheel drive vehicles. Further, as a by-wire brake system, the input device 14 and the motor cylinder device 16 are electrically connected to a control means such as an ECU through a harness (not shown).

FIG. 2 is a schematic configuration diagram of the vehicle brake system.
The hydraulic path will be described. The connection port 20a of the input device 14 and the connection point A1 are connected by the first piping tube 22a with the connection point A1 in FIG. 2 as a reference, and the output port 24a of the motor cylinder device 16 And the connection point A1 are connected by the second piping tube 22b, and the introduction port 26a of the VSA device 18 and the connection point A1 are connected by the third piping tube 22c.

  With reference to another connection point A2 in FIG. 2, the other connection port 20b of the input device 14 and the connection point A2 are connected by the fourth piping tube 22d, and the other output port 24b of the motor cylinder device 16 is connected. The connection point A2 is connected by the fifth piping tube 22e, and the other introduction port 26b of the VSA device 18 and the connection point A2 are connected by the sixth piping tube 22f.

  The VSA device 18 is provided with a plurality of outlet ports 28a to 28d. The first outlet port 28a is connected to the wheel cylinder 32FR of the disc brake mechanism 30a provided on the right front wheel by the seventh piping tube 22g. The second outlet port 28b is connected to the wheel cylinder 32RL of the disc brake mechanism 30b provided on the left rear wheel by the eighth piping tube 22h. The third outlet port 28c is connected to the wheel cylinder 32RR of the disc brake mechanism 30c provided on the right rear wheel by the ninth piping tube 22i. The fourth outlet port 28d is connected to the wheel cylinder 32FL of the disc brake mechanism 30d provided on the left front wheel by the tenth piping tube 22j.

  In this case, brake fluid (brake fluid) is supplied to the wheel cylinders 32FR, 32RL, 32RR, 32FL of the disc brake mechanisms 30a-30d by the piping tubes 22g-22j connected to the outlet ports 28a-28d, As the hydraulic pressure in the wheel cylinders 32FR, 32RL, 32RR, and 32FL increases, each wheel cylinder 32FR, 32RL, 32RR, and 32FL operates, and the corresponding wheel (right front wheel, left rear wheel, right rear wheel, left front wheel). ) Is applied with braking force.

  The vehicle brake system 10 is provided so as to be mountable on various vehicles including, for example, an automobile driven only by an engine (internal combustion engine), a hybrid automobile, an electric automobile, and a fuel cell automobile.

  The input device 14 includes a tandem master cylinder 34 that can generate hydraulic pressure by operating the brake pedal 12 by a driver, and a first reservoir 36 attached to the master cylinder 34. In the cylinder tube 38 of the master cylinder 34, a second piston 40a and a first piston 40b that are spaced apart from each other by a predetermined distance along the axial direction of the cylinder tube 38 are slidably disposed. The second piston 40 a is disposed close to the brake pedal 12 and is connected to the brake pedal 12 via the push rod 42. Further, the first piston 40b is arranged farther from the brake pedal 12 than the second piston 40a.

  A pair of cup seals 44a and 44b are respectively attached to the outer peripheral surfaces of the second piston 40a and the first piston 40b via an annular step portion. Back chambers 48a and 48b communicating with supply ports 46a and 46b, which will be described later, are formed between the pair of cup seals 44a and 44b, respectively. Further, a spring member 50a is disposed between the second piston 40a and the first piston 40b, and another spring member 50b is disposed between the first piston 40b and the front end portion of the cylinder tube 38. Is done.

  Instead of providing cup seals 44a and 44b on the outer peripheral surfaces of the second piston 40a and the first piston 40b, cup seals may be provided on the inner peripheral surface of the cylinder tube 38, respectively.

  The cylinder tube 38 of the master cylinder 34 is provided with two supply ports 46a and 46b, two relief ports 52a and 52b, and two output ports 54a and 54b. In this case, each supply port 46a (46b) and each relief port 52a (52b) are provided so as to join and communicate with a reservoir chamber (not shown) in the first reservoir 36, respectively.

  Further, in the cylinder tube 38 of the master cylinder 34, a second pressure chamber 56a and a first pressure chamber 56b for generating a brake fluid pressure corresponding to the depression force of the driver depressing the brake pedal 12 are provided. The second pressure chamber 56a is provided so as to communicate with the connection port 20a via the second hydraulic pressure path 58a, and the first pressure chamber 56b communicates with the other connection port 20b via the first hydraulic pressure path 58b. To be provided.

  A pressure sensor Pm is disposed between the master cylinder 34 and the connection port 20a upstream of the second hydraulic pressure path 58a, and a normally open type is provided downstream of the second hydraulic pressure path 58a. A second shut-off valve 60a composed of a (normally open) solenoid valve is provided. This pressure sensor Pm detects the hydraulic pressure upstream of the second shutoff valve 60a on the master cylinder 34 side on the second hydraulic pressure path 58a.

  Between the master cylinder 34 and the other connection port 20b, on the upstream side of the first hydraulic pressure path 58b, a first shutoff valve 60b composed of a normally open type (normally open type) solenoid valve is provided. A pressure sensor Pp is provided on the downstream side of the first hydraulic pressure path 58b. The pressure sensor Pp detects the hydraulic pressure downstream of the wheel cylinders 32FR, 32RL, 32RR, 32FL from the first shutoff valve 60b on the first hydraulic pressure path 58b.

  The normal open in the second shut-off valve 60a and the first shut-off valve 60b is a valve configured such that the normal position (the position of the valve body at the time of demagnetization (non-energization)) is in the open position (normally open). Say. In FIG. 2, the second shut-off valve 60a and the first shut-off valve 60b show the state at the time of excitation (the same applies to the third shut-off valve 62 described later).

  A branch hydraulic pressure path 58c branched from the first hydraulic pressure path 58b is provided in the first hydraulic pressure path 58b between the master cylinder 34 and the first shutoff valve 60b, and the branched hydraulic pressure path 58c includes A third shut-off valve 62 composed of a normally closed type (normally closed type) solenoid valve and a stroke simulator 64 are connected in series. The normal close in the third shut-off valve 62 refers to a valve configured such that the normal position (the position of the valve body at the time of demagnetization (non-energization)) is in the closed position (normally closed).

  The stroke simulator 64 is disposed on the first hydraulic pressure path 58b and closer to the master cylinder 34 than the first shutoff valve 60b. The stroke simulator 64 is provided with a hydraulic pressure chamber 65 communicating with the branch hydraulic pressure path 58c, and the brake fluid derived from the first pressure chamber 56b of the master cylinder 34 can be absorbed via the hydraulic pressure chamber 65. Is provided.

  The stroke simulator 64 is a simulator that is urged by a first return spring 66a having a high spring constant, a second return spring 66b having a low spring constant, and the first and second return springs 66a and 66b arranged in series. A piston 68, the pedal reaction force increase gradient is set low when the brake pedal 12 is depressed, and the pedal reaction force is set high when the brake pedal 12 is depressed late, so that the pedal feeling of the brake pedal 12 is equivalent to that of the existing master cylinder. It is provided to become.

  The hydraulic pressure path is roughly classified into a second hydraulic pressure system 70a that connects the second pressure chamber 56a of the master cylinder 34 and the plurality of wheel cylinders 32FR and 32RL, a first pressure chamber 56b of the master cylinder 34, and a plurality of pressure paths. The first hydraulic system 70b is connected to the wheel cylinders 32RR and 32FL.

  The second hydraulic system 70a includes a second hydraulic path 58a that connects the output port 54a of the master cylinder 34 (cylinder tube 38) and the connection port 20a in the input device 14, and the connection port 20a of the input device 14 and the motor cylinder. Piping tubes 22a and 22b connecting the output port 24a of the device 16, piping tubes 22b and 22c connecting the output port 24a of the motor cylinder device 16 and the introduction port 26a of the VSA device 18, and a lead-out port of the VSA device 18 The pipe tubes 22g and 22h connect the 28a and 28b and the wheel cylinders 32FR and 32RL, respectively.

  The first hydraulic system 70b includes a first hydraulic path 58b that connects the output port 54b of the master cylinder 34 (cylinder tube 38) in the input device 14 and the other connection port 20b, and another connection port of the input device 14. Piping tubes 22d and 22e that connect 20b and the output port 24b of the motor cylinder device 16, piping tubes 22e and 22f that connect the output port 24b of the motor cylinder device 16 and the introduction port 26b of the VSA device 18, and a VSA device 18 lead-out ports 28c, 28d and pipe tubes 22i, 22j connecting the wheel cylinders 32RR, 32FL, respectively.

  The motor cylinder device 16 is an electric brake device that generates brake fluid pressure by driving the second slave piston 88a and the first slave piston 88b in the axial direction by the driving force of the electric motor 72. In the motor cylinder device 16, the moving direction (in the direction of arrow X1 in FIG. 2) of the second slave piston 88a and the first slave piston 88b when generating (raising) the brake fluid pressure is set to “front” and vice versa. The direction (arrow X2 direction in FIG. 2) is “rear”.

  The motor cylinder device 16 includes a cylinder portion 76 having a second slave piston 88a and a first slave piston 88b that are movable in the axial direction, and a motor 72 for driving the second slave piston 88a and the first slave piston 88b. And a driving force transmission unit 73 for transmitting the driving force of the motor 72 to the second slave piston 88a and the first slave piston 88b.

  The second slave piston 88a is formed integrally with the second cylindrical member 88a1 fixed along the outer periphery of the second slave piston 88a in the front-rear direction of the second slave piston 88a. Then, as the second cylindrical member 88a1 slides inside the cylinder portion 76, the second slave piston 88a is driven in the front-rear direction. The first slave piston 88b is also formed integrally with the first cylindrical member 88b1 fixed along the outer periphery of the first slave piston 88b in front of the first slave piston 88b. Then, as the first cylindrical member 88b1 slides inside the cylinder portion 76, the first slave piston 88b is driven in the front-rear direction.

  The driving force transmission unit 73 includes a gear mechanism (deceleration mechanism) 78 that transmits the rotational driving force of the motor 72, and a ball screw structure 80 that converts this rotational driving force into a linear driving force of a ball screw shaft (screw) 80a. And a driving force transmission mechanism 74 including

  The cylinder part 76 includes a substantially cylindrical cylinder body 82 and a second reservoir 84 attached to the cylinder body 82. The second reservoir 84 is connected to the first reservoir 36 attached to the master cylinder 34 of the input device 14 by a piping tube 86, and the brake fluid stored in the first reservoir 36 is passed through the piping tube 86 to the second reservoir 84. 84 is provided so as to be supplied in the inside.

  In the cylinder main body 82, as described above, the second slave piston 88a and the first slave piston 88b that are spaced apart from each other by a predetermined distance along the axial direction of the cylinder main body 82 are arranged to be freely driven. The second slave piston 88a is disposed close to the ball screw structure 80, contacts the front end of the ball screw shaft 80a, and is displaced integrally with the ball screw shaft 80a in the direction of the arrow X1 or X2. The first slave piston 88b is arranged farther from the ball screw structure 80 side than the second slave piston 88a.

  A slave cup seal 90a (seal member) that seals the space between the outer peripheral surface of the second cylindrical member 88a1 fixed to the second slave piston 88a and the driving force transmission mechanism 74 is provided on the cylinder portion 76 side. Is done. A slave cup seal 90b (seal member) is also provided on the cylinder portion 76 side so as to be separated from the slave cup seal 90a, and a reservoir port 92a, which will be described later, is provided between the slave cup seal 90a and the slave cup seal 90b. A communicating channel port is provided. A second return spring 96a is disposed between the second slave piston 88a and the first slave piston 88b. Further, on the opposite side of the slave cup seal 90b in the slave cup seal 90a, a slave cup seal 90e (seal member) and a liquid reservoir 91 are provided on the cylinder portion 76 side. By providing the slave cup seal 90e and the liquid reservoir 91, a more liquid-tight seal can be achieved.

  On the other hand, a slave cup seal 90c (seal member) that provides a fluid-tight seal between the outer peripheral surface of the first cylindrical member 88b1 fixed to the first slave piston 88b and a first hydraulic pressure chamber 98b described later is a cylinder portion. It is arranged on the 76 side. Further, the second hydraulic pressure chamber 98a, which will be described later, is liquid-tightly sealed by the slave cup seal 90b and the slave cup seal 90c.

  In addition, a slave cup seal 90d (seal member) that seals the first hydraulic chamber 98b in a liquid-tight manner is provided on the cylinder portion 76 side, apart from the slave cup seal 90c. Furthermore, between the slave cup seal 90c and the slave cup seal 90d, a flow path port communicating with a reservoir port 92b described later is provided. A first return spring 96b is disposed between the first slave piston 88b and the lid member 82c that closes the opening of the cylinder body 82 (that is, the opening provided at the front end of the cylinder portion 76).

  By forming the front end of the cylinder body 82 with an opening, the opening facilitates processing of the inner wall near the opening. Therefore, the inside of the cylinder body 82 shown in FIG. 2 can be formed easily and accurately. In particular, when the cylinder length of the cylinder main body 82 constituting the cylinder portion 76 is increased, both ends of the cylinder main body 82 are open, so that the fixed processing tools can be inserted into the cylinder main body 82 from both ends. Since each processing tool is fixed in this manner, the processing tool has high rigidity, and as a result, it can be easily processed with high accuracy even in the vicinity of the inner center of the cylinder body 82. That is, it is possible to use a cylinder having a cylinder length that has conventionally been difficult to use from the viewpoint of accuracy.

  Further, since the front end of the cylinder body 82 is formed by opening the front end, it is possible to improve the assembling property when a piston or the like is disposed inside the cylinder body 82.

  Further, by arranging the slave cup seals 90a, 90b, 90c, 90d and 90e on the cylinder portion 76 side, it is possible to obtain a plunger-type slave cylinder which is difficult to apply to the conventional slave cylinder. Further, by providing the slave cup seals 90a, 90b, 90c, 90d and 90e, the structure of the first slave piston 88b and the second slave piston 88a can be simplified, and the processing of the slave piston becomes easy. In addition, since it can be surely sealed with a simple structure, the number of parts can be reduced.

  Furthermore, since each slave cup seal does not move even if the first slave piston 88b and the second slave piston 88a move, it is possible to suppress wear of each slave cup seal as compared with the conventional case. In addition, since the position of each slave cup seal is fixed, the guide length behind the slave cup seal 90a does not fluctuate when the second slave piston 88a moves forward. It can be kept stable.

  The cylinder body 82 of the cylinder portion 76 is provided with two reservoir ports 92a and 92b and two output ports 24a and 24b. In this case, the reservoir port 92 a (92 b) is provided so as to communicate with the reservoir chamber in the second reservoir 84.

  Further, in the cylinder body 82, a second hydraulic pressure chamber 98a for generating a brake hydraulic pressure output from the output port 24a to the wheel cylinders 32FR and 32RL side, and the other output port 24b to the wheel cylinders 32RR and 32FL side. A first hydraulic pressure chamber 98b for generating the output brake hydraulic pressure is provided.

  Further, a regulating means 102 for regulating the sliding range of the first slave piston 88b is provided between the first slave piston 88b and the lid member 82c that closes the opening of the cylinder portion 76. This prevents overreturn of the first slave piston 88b to the second slave piston 88a side. In particular, at the time of backup in which braking is performed with the brake fluid pressure generated in the master cylinder 34, when one system fails, Failure is prevented. Further, a restricting means 103 for restricting the maximum separation distance and the minimum separation distance between the first slave piston 88b and the second slave piston 88a is also provided between the first slave piston 88b and the second slave piston 88a.

  The regulating means 102 slides inside the cylindrical member 102b, the cylindrical member 102b fixed between the cylinder main body 82 and the lid member 82c via the flange portion 102b1, and the first slave piston 88b and the connecting member And a first regulating piston 102a connected by 102a1. That is, the flange portion 102b1 constituting the restricting means 102 is sandwiched and fixed between the cylinder body 82 (that is, the cylinder portion 76) and the lid member 82c by screwing or the like (not shown). And the sliding range of the 1st slave piston 88b connected to the 1st control piston 102a is controlled because the 1st control piston 102a slides in the cylindrical member 102b.

  Further, the regulating means 103 is connected to the first slave piston 88b and fixed to the cylindrical member 103b, slides inside the cylindrical member 103b, and is connected by the second slave piston 88a and the connecting member 103a1. And a second regulating piston 103a. And the sliding range of the 2nd slave piston 88a connected to the 2nd control piston 103a is controlled because the 2nd control piston 103a slides in the cylindrical member 103b.

  The VSA device 18 is a well-known one, and a second brake system that controls a second hydraulic system 70a connected to the disc brake mechanisms 30a, 30b (wheel cylinder 32FR, wheel cylinder 32RL) of the right front wheel and the left rear wheel. 110a and a first brake system 110b for controlling the first hydraulic system 70b connected to the disc brake mechanisms 30c, 30d (wheel cylinder 32RR, wheel cylinder 32FL) of the right rear wheel and the left front wheel.

  In addition, the combination of the connection between the second brake system 110a and the first brake system 110b and each of the disc brake mechanisms 30a, 30b, 30c, and 30d is not limited to the combination described above, and two independent systems are secured. For example, the following combinations are possible. That is, although not shown, the second brake system 110a includes a hydraulic system connected to a disc brake mechanism provided on the left front wheel and the right front wheel, and the first brake system 110b includes the left rear wheel and the right rear wheel. It may be a hydraulic system connected to a disc brake mechanism provided in the. Further, the second brake system 110a includes a hydraulic system connected to a disc brake mechanism provided on the right front wheel and the right rear wheel on one side of the vehicle body, and the first brake system 110b includes the left front wheel and the left rear wheel on the vehicle body side. A hydraulic system connected to a disc brake mechanism provided on the wheel may be used. The second brake system 110a includes a hydraulic system connected to a disc brake mechanism provided on the right front wheel and the left front wheel, and the first brake system 110b includes a disc provided on the right rear wheel and the left rear wheel. A hydraulic system connected to the brake mechanism may be used.

  Since the second brake system 110a and the first brake system 110b have the same structure, the corresponding parts in the second brake system 110a and the first brake system 110b are assigned the same reference numerals, and the second brake system The description of the first brake system 110b will be added in parentheses as appropriate, with a focus on the description of the system 110a.

  The second brake system 110a (first brake system 110b) has a first common hydraulic pressure path 112 and a second common hydraulic pressure path 114 that are common to the wheel cylinders 32FR and 32RL (32RR and 32FL). The VSA device 18 includes a regulator valve 116 formed of a normally open type solenoid valve disposed between the introduction port 26a and the first common hydraulic pressure path 112, and arranged in parallel with the regulator valve 116 from the introduction port 26a side. A first check valve 118 that permits the flow of brake fluid to the first common hydraulic pressure passage 112 side (blocks the flow of brake fluid from the first common hydraulic pressure passage 112 side to the introduction port 26a side); A first in-valve 120 composed of a normally open type solenoid valve disposed between the common hydraulic pressure path 112 and the first outlet port 28a, and a first inlet valve 120 disposed in parallel with the first inlet valve 120 from the first outlet port 28a side. Allow the brake fluid to flow to the first common hydraulic pressure passage 112 side (from the first common hydraulic pressure passage 112 side to the first outlet port) A second in-valve comprising a second check valve 122 (which prevents the flow of brake fluid to the 8a side) and a normally open type solenoid valve disposed between the first common hydraulic pressure passage 112 and the second outlet port 28b. 124 and the second inlet valve 124 are arranged in parallel to allow the brake fluid to flow from the second lead-out port 28b side to the first common hydraulic pressure path 112 side (second lead-out from the first common hydraulic pressure path 112 side). And a third check valve 126 for inhibiting the flow of brake fluid to the port 28b side.

  Further, the VSA device 18 includes a first out valve 128 including a normally closed solenoid valve disposed between the first outlet port 28a and the second common hydraulic pressure path 114, a second outlet port 28b, and a second outlet port 28b. A second out valve 130 composed of a normally closed solenoid valve disposed between the common hydraulic pressure path 114, a reservoir 132 connected to the second common hydraulic pressure path 114, and a first common hydraulic pressure path 112; It is arranged between the second common hydraulic pressure path 114 and allows the brake fluid to flow from the second common hydraulic pressure path 114 side to the first common hydraulic pressure path 112 side (from the first common hydraulic pressure path 112 side). The fourth check valve 134 (which prevents the flow of brake fluid to the second common hydraulic pressure path 114 side) is disposed between the fourth check valve 134 and the first common hydraulic pressure path 112, and the second common hydraulic pressure path 112 is disposed. A pump 136 that supplies brake fluid from the hydraulic pressure path 114 side to the first common hydraulic pressure path 112 side, an intake valve 138 and a discharge valve 140 provided before and after the pump 136, and a motor M that drives the pump 136, And a suction valve 142 formed of a normally closed solenoid valve disposed between the second common hydraulic pressure path 114 and the introduction port 26a.

  In the second brake system 110a, the brake fluid generated in the second hydraulic chamber 98a of the motor cylinder device 16 is output from the output port 24a of the motor cylinder device 16 on the hydraulic pressure path close to the introduction port 26a. A pressure sensor Ph for detecting pressure is provided. Detection signals detected by the pressure sensors Pm, Pp, and Ph are introduced into control means (not shown).

  The vehicle brake system 10 according to the present embodiment is basically configured as described above. Next, the operation and effect will be described.

  When the vehicle brake system 10 functions normally, the second shut-off valve 60a and the first shut-off valve 60b, which are normally open type solenoid valves, are energized to be closed, and a third shut-off type solenoid valve is used. The shut-off valve 62 is opened by excitation (see FIG. 2). Accordingly, since the second hydraulic pressure system 70a and the first hydraulic pressure system 70b are blocked by the second cutoff valve 60a and the first cutoff valve 60b, the brake hydraulic pressure generated in the master cylinder 34 of the input device 14 is applied to the disc brake. It is not transmitted to the wheel cylinders 32FR, 32RL, 32RR, 32FL of the mechanisms 30a to 30d.

  At this time, the brake hydraulic pressure generated in the first pressure chamber 56b of the master cylinder 34 is transmitted to the hydraulic pressure chamber 65 of the stroke simulator 64 via the branch hydraulic pressure path 58c and the third shut-off valve 62 in the valve open state. Is done. The simulator piston 68 is displaced against the spring force of the return springs 66a and 66b by the brake hydraulic pressure supplied to the hydraulic pressure chamber 65, so that the stroke of the brake pedal 12 is allowed and a pseudo pedal reaction is achieved. A force is generated and applied to the brake pedal 12. As a result, it is possible to obtain a brake feeling that is comfortable for the driver.

  In such a system state, the control means (not shown) drives the motor 72 of the motor cylinder device 16 and detects the driving force of the motor 72 via the driving force transmission mechanism 74 when detecting the depression of the brake pedal 12 by the driver. Then, the second slave piston 88a and the first slave piston 88b are displaced in the direction of arrow X1 in FIG. 2 against the spring force of the second return spring 96a and the first return spring 96b. Due to the displacement of the second slave piston 88a and the first slave piston 88b, the brake fluid in the second fluid pressure chamber 98a and the first fluid pressure chamber 98b is pressurized so as to be balanced to generate a desired brake fluid pressure.

  The brake hydraulic pressure in the second hydraulic pressure chamber 98a and the first hydraulic pressure chamber 98b in the motor cylinder device 16 is supplied to the disc brake mechanism 30a via the first and second inlet valves 120 and 124 in the valve open state of the VSA device 18. To 30d wheel cylinders 32FR, 32RL, 32RR, 32FL, and the wheel cylinders 32FR, 32RL, 32RR, 32FL are operated to apply a desired braking force to each wheel.

  In other words, in the vehicle brake system 10 according to the present embodiment, the motor cylinder device 16 that functions as an electric brake device (power hydraulic pressure source) and a control unit such as an ECU (not shown) that performs by-wire control can operate normally. , The communication between the master cylinder 34 that generates brake fluid pressure when the driver steps on the brake pedal 12 and the disc brake mechanisms 30a to 30d (wheel cylinders 32FR, 32RL, 32RR, and 32FL) that brake each wheel is second. A so-called brake-by-wire brake system is activated in which the disc brake mechanisms 30a to 30d are operated by the brake fluid pressure generated by the motor cylinder device 16 in a state of being shut off by the shut-off valve 60a and the first shut-off valve 60b. Become. For this reason, in this embodiment, for example, it can be suitably applied to a vehicle such as an electric vehicle that does not have negative pressure due to an internal combustion engine that has been used for a long time.

  On the other hand, when the motor cylinder device 16 or the like is inoperable, the second cutoff valve 60a and the first cutoff valve 60b are opened, and the third cutoff valve 62 is closed and the master cylinder 34 is closed. The generated brake fluid pressure is transmitted to the disc brake mechanisms 30a to 30d (wheel cylinders 32FR, 32RL, 32RR, and 32FL), and the disc brake mechanisms 30a to 30d (wheel cylinders 32FR, 32RL, 32RR, and 32FL) are operated. The so-called traditional hydraulic brake system becomes active.

  Next, the motor cylinder device 16 will be described in more detail. FIG. 3 is a side view of the motor cylinder device. FIG. 4 is an exploded perspective view of the motor cylinder device. FIG. 5 is an exploded perspective view of the driving force transmission unit.

  As shown in FIG. 3, the motor cylinder device 16 includes the cylinder portion 76, the motor 72, and the driving force transmission portion 73 as described above. The motor 72 is driven based on an electrical signal from a control means (not shown).

  Here, the motor 72 is positioned above the cylinder portion 76. If comprised in this way, it can prevent that the oil components, such as the grease in the driving force transmission part 73, enter | penetrate in the motor 72 by the effect | action of gravity, and invade the electrical component etc. which are not shown in figure.

  As shown in FIG. 4, the motor 72, the driving force transmission unit 73, and the cylinder unit 76 are configured to be separable from each other. The motor 72 has a base portion 161 to which a harness (not shown) is connected, and a plurality of through holes 162 into which the bolts 201 are inserted are formed in the base portion 161. Further, a flange portion 82a is provided at the end of the cylinder portion 76 on the driving force transmission portion 73 side of the cylinder body 82, and a plurality of through holes 82b through which the bolts 202 are inserted are formed in the flange portion 82a. Yes.

  The driving force transmission unit 73 includes a housing 171 that houses therein a driving force transmission mechanism 74 (see FIG. 5) including a gear mechanism 78 and a ball screw structure 80. The housing 171 is disposed on the cylinder unit 76 side. A case 172 to be disposed and a cover 173 that covers an opening end of the case 172 opposite to the cylinder portion 76 are provided. The case 172 and the cover 173 of the driving force transmission unit 73 are made of a light metal such as an aluminum alloy (the same applies to the cylinder body 82 of the cylinder unit 76).

  A plurality of screw holes 174 for motor attachment for attaching the motor 72 to the driving force transmission unit 73 are formed in the case 172 of the driving force transmission unit 73. Further, a flange portion 175 is provided at an end portion of the case 172 on the cylinder portion 76 side, and a cylinder portion mounting screw hole 176 for attaching the cylinder portion 76 to the driving force transmitting portion 73 is provided in the flange portion 175. A plurality of are formed.

  The motor 72 is attached and fixed to the driving force transmitting portion 73 by inserting the bolt 201 into the through hole 162 and screwing it into the motor mounting screw hole 174. Further, the cylinder portion 76 is attached and fixed to the driving force transmitting portion 73 by inserting the bolt 202 through the through hole 82b and screwing it into the cylinder portion attaching screw hole 176.

  As shown in FIG. 5, a gear mechanism 78 and a ball screw structure 80 are accommodated in a housing 171 (see FIG. 4). The gear mechanism 78 includes a pinion gear 78a (see FIG. 2) fixed to the output shaft of the motor 72, an idle gear 78b meshed with the pinion gear 78a, and a ring gear 78c meshed with the idle gear 78b. Yes.

  The ball screw structure 80 is provided with a nut 80c that rotates by receiving the rotational driving force of the motor 72, and is engaged (screwed) with the nut 80c so as to be movable in the axial direction, and the front end thereof is the second slave piston 88a. And a ball screw shaft 80a (screw) that presses the second slave piston 88a (piston) and a ball 80b (see FIG. 2) that is arranged to roll in a thread groove on the ball screw shaft 80a. ing.

  The nut 80c is engaged with the inner peripheral surface of the ring gear 78c via, for example, a key. However, the engagement between the nut 80c and the ring gear 78c is not limited to the engagement through the key, and for example, the outer peripheral surface of the nut 80c may be press-fitted into the inner peripheral surface of the ring gear 78c. Thereby, after the rotational driving force transmitted from the gear mechanism 78 is input to the nut 80c, it is converted into a linear driving force by the ball screw structure 80, and the ball screw shaft 80a can move along the axial direction. Has been.

  The case 172 and the cover 173 of the housing 171 (see FIG. 4) are configured to be separable from each other. A plurality of through holes 177 into which the bolts 203 are inserted are formed in the case 172 so as to be positioned around the central axis CL (see FIG. 4) of the second slave piston 88a and the first slave piston 88b (see FIG. 2). A plurality of case mounting screw holes 178 are formed at positions corresponding to the through holes 177 of the cover 173. Then, the case 172 and the cover 173 are coupled to each other by inserting the bolt 203 through the through hole 177 and screwing it into the case mounting screw hole 178.

  5 indicates a bearing that rotatably supports the tip of the output shaft of the motor 72. The bearing 179 is fitted into a hole 180 formed in the cover 173. Further, a cylindrical pin 220 as a restricting portion for preventing rotation of the ball screw shaft 80a is, for example, press-fitted into a through hole formed along a direction perpendicular to the axial direction of the ball screw shaft 80a. It is provided on the ball screw shaft 80a. On the other hand, the cover 173 of the housing 171 is formed with a sliding groove 211 as a guide portion that supports the pin 220 so as to be movable in the axial direction of the ball screw shaft 80a.

FIG. 6 is a perspective view of the motor cylinder device as viewed obliquely from below.
As shown in FIG. 6, the motor cylinder device 16 is provided with a mount portion 181 for attaching the motor cylinder device 16 to the vehicle body 1 (see FIG. 1) such as a side frame. The mount portion 181 has a left mount hole 182 located on the left side, a right mount hole 183 located on the right side, and a lower mount hole located below when viewed from the cover 173 side in the direction of the central axis CL (see FIG. 4). 184. The left and right lower mounting holes 182 to 184 each have a cylindrical recess in which a rubber bush (not shown) for floating support can be mounted. The mount portion 181 has a through hole 185 formed along the common axis of the left mount hole 182 and the right mount hole 183 and having an axis perpendicular to the central axis CL (see FIG. 4).

  The mount 181 is provided in the vicinity of the center of gravity of the motor cylinder device 16. Here, the mount portion 181 is provided on the case 172 of the driving force transmission portion 73. According to such a configuration, the vicinity of the center of gravity of the motor cylinder device 16 can be supported, and the shake can be reduced even when receiving a force such as vibration.

  The motor cylinder device 16 is attached to the vehicle body 1 such as a side frame (see FIG. 1) via a mounting bracket (not shown) by the mount portion 181. Here, the left mount hole 182 and the right mount hole 183 are configured to be fastened to the vehicle body side by a single bolt 204 inserted through the through hole 185, and the mounting operation of the motor cylinder device 16 becomes easy. Yes. By using such a mount portion 181, it is possible to attach the motor cylinder device 16 to the vehicle body side while supporting the left and right three points of the motor cylinder device 16.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to the structure described in the said embodiment, Including suitably combining thru | or selecting the structure described in embodiment, The configuration can be changed as appropriate without departing from the spirit of the invention.

  In the above-described embodiment, the so-called tandem cylinder portion 76 including the second slave piston 88a and the first slave piston 88b arranged side by side in the central axis CL direction (see FIG. 4) has been described. However, the present invention is not limited to this, and can of course be applied to an electric brake device having a cylinder portion having one piston and one hydraulic chamber formed in front of the piston.

  Further, as shown in FIG. 7, a stepped portion 104 may be provided on the inner wall of the cylinder body 82. In the electric brake device shown in FIG. 7, the first slave piston 88b comes into contact with the stepped portion 104, so that the overreturn of the first slave piston 88b toward the second slave piston 88a can be more reliably prevented. .

  In the above embodiment, the restricting means 102 is fixed by the flange portion 102b1 being sandwiched between the cylinder body 82 and the lid member 82c. ) May be fixed by welding or the like.

  In the above embodiment, the lid member 82c is provided so that the outer circumferential surface of the lid member 82c and the outer circumferential surface of the cylinder body 82 coincide with each other, but the lid member 82c is inserted into the opening of the cylinder body 82. The cylinder body 82 may be closed.

14 Input device 16 Motor cylinder device (electric brake device)
18 VSA device 72 Motor 76 Cylinder portion 82 Cylinder body 82c Lid members 90a, 90b, 90c, 90d Slave cup seal (seal member)
102 regulating means 103 regulating means 104 stepped part 172 case (supporting part)

Claims (3)

A cylinder part with a built-in piston that can move forward and backward,
A motor for driving the piston;
A driving force transmission mechanism for transmitting the driving force of the motor to the piston, and an electric brake device that generates a brake fluid pressure by driving the piston forward by the driving force of the motor,
The cylinder portion is formed by opening an end opposite to the side where the driving force transmission mechanism is disposed, and the opposite end is closed by a lid member,
An electric brake device, characterized in that a restricting means is provided between the lid member and the piston so that the driving position of the piston within the cylinder portion falls within a predetermined range. The lid member and the regulating means are molded separately,
2. The electric brake device according to claim 1, wherein the restricting unit is sandwiched and fixed between the lid member and the cylinder portion. A cylinder part with a built-in piston that can move forward and backward,
A motor for driving the piston;
A driving force transmission mechanism for transmitting the driving force of the motor to the piston, and an electric brake device that generates a brake fluid pressure by driving the piston forward by the driving force of the motor,
The cylinder portion is formed by opening an end opposite to the side where the driving force transmission mechanism is disposed, and the opposite end is closed by a lid member,
A stepped portion is formed on the inner wall of the cylinder portion so that the inner diameter of the opposite end portion is larger than the end portion on the side where the driving force transmission mechanism is disposed,
The electric brake device according to claim 1, wherein a seal member for preventing leakage of brake fluid in the cylinder portion is provided in the cylinder portion.

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