JP2012210831A - Hydraulic pressure generation device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic pressure generation device for a vehicle which is easy to be assembled in a car body, with less number of assembly steps.SOLUTION: The hydraulic pressure generation device for a vehicle includes a hydraulic pressure generating means (master cylinder 34) which generates a hydraulic pressure according to action of a brake pedal by a driver, a rear piston member (second piston 40a) which is stored in the hydraulic pressure generating means, to be provided on the brake pedal side, and a front piston member (first piston 40b) which is arranged in front of the rear piston member. It includes a rod connection member 43 which is stored in the hydraulic pressure generating means and is connected to the tip end of a push rod 42 of the brake pedal, and a spring member 45 which is arranged between the rear piston member and the rod connection member.

Description

  The present invention relates to a vehicle hydraulic pressure generator used in a vehicle brake device.

  2. Description of the Related Art Conventionally, a brake device is known that improves the pedal feel by reducing the step feeling of pedal operation when a driver depresses a brake pedal to generate hydraulic pressure in a master cylinder of the brake device (for example, patents). Reference 1). Next, FIG. 5 referred to is an explanatory diagram of the configuration of a conventional master cylinder.

As shown in FIG. 5, the brake device includes coil springs 250 a and 250 b, and a master cylinder 238 containing a front piston 240 b and a rear piston 240 a that are biased rearward (right side in FIG. 5), A push rod 242 inserted into the rear portion of the rear piston 240a with a clearance α, and a reaction force spring 245 that applies a reaction force when a load is input to the push rod 242 via the brake pedal 212. ing.
This brake device moves the push rod 242 forward until the clearance α is eliminated while generating a reaction force by the reaction force spring 245 before the coil springs 250a and 250b apply a reaction force to the brake pedal 212. Thereafter, the front piston 240b and the rear piston 240a are moved forward by the push rod 242 that is in contact with the rear piston 240a.

  According to this brake device, before the push rod 242 comes into contact with the rear piston 240a, in other words, before the front piston 240b and the rear piston 240a are moved forward, the reaction force spring 245 is applied to the push rod 242. Therefore, it is possible to reduce the stepped feeling of pedal operation when the hydraulic pressure is generated in the master cylinder 238.

International Publication No. 2010/055842 Pamphlet

  However, in this brake device, it is necessary to support one end of the reaction force spring 245 at the rear end of the master cylinder 238 and to support the other end on the brake pedal 212 side. Further, the push rod 242 needs to be assembled while maintaining a predetermined clearance α with respect to the rear piston 240a of the master cylinder 238. On the other hand, the push rod 242 is biased in a direction in which the push rod 242 is pulled away from the rear piston 240a. The reaction force spring 245 is assembled. Therefore, in this brake device, there is a problem that it is difficult to assemble the master cylinder 238 to the vehicle body (for example, dashboard lower) and the number of assembling steps increases.

  Therefore, the present invention is to provide a vehicle hydraulic pressure generator that can be easily assembled to a vehicle body and can reduce the number of assembly steps.

The present invention that has solved the above problems includes a hydraulic pressure generating means that generates hydraulic pressure in response to a driver's operation of a brake pedal, and a rear piston that is housed inside the hydraulic pressure generating means and provided on the brake pedal side. In the vehicle hydraulic pressure generator having a member and a front piston member disposed in front of the rear piston member, the hydraulic pressure generator for a vehicle is accommodated in the hydraulic pressure generating means and connected to a tip of a push rod of the brake pedal. A rod connecting member, and a spring member disposed between the rear piston member and the rod connecting member.
The vehicle hydraulic pressure generator according to the present invention is different from a conventional brake device (see, for example, Patent Document 1), and a push rod of a brake pedal includes a rear piston member (a rear piston of a master cylinder constituting the conventional brake device). The rod connecting member is newly provided in the hydraulic pressure generating means (corresponding to the conventional master cylinder), and the push rod is assembled to the rod connecting member. It has a configuration. A spring member is provided between the rod connecting member and the rear piston.
Therefore, according to such a hydraulic pressure generator for a vehicle, unlike a master cylinder (see, for example, Patent Document 1) constituting a conventional brake device, a predetermined gap α is not provided between the master cylinder and the master cylinder. Since this can be assembled to the vehicle body, the ease of assembly to the vehicle body is further improved.
Further, according to this hydraulic pressure generator for a vehicle, unlike a master cylinder (for example, see Patent Document 1) that constitutes a conventional brake device, when this is attached to a vehicle body, the gap between the master cylinder and the push rod is reduced. Since there is no need to provide a reaction force spring, the number of assembling steps can be reduced.

In this vehicular hydraulic pressure generating device, the hydraulic pressure generating means communicates with a normally open shut-off valve, and an electric hydraulic pressure generating means operated by an electric actuator, and communicated with the hydraulic pressure generating means. A rod simulator provided through a normally closed reaction force permission valve to apply a reaction force to the brake pedal; and an operation amount detection means for detecting an operation amount of the brake pedal, the rod connecting member Until the rear piston member abuts, the shut-off valve is closed and the reaction force permission valve is opened based on the operation amount of the brake pedal detected by the operation amount detection means.
In general, a vehicle hydraulic pressure generator for an electric brake system, in normal use, brakes the vehicle with the hydraulic pressure electrically generated by the electric hydraulic pressure generating means and communicates with the hydraulic pressure generating means. A reaction force is applied to the brake pedal by the stroke simulator. In the case of fail-safe such as when the hydraulic pressure generation means has hindered the generation of hydraulic pressure, the normally open shut-off valve provided between the hydraulic pressure generation means and the electric hydraulic pressure generation means is opened. By controlling the valve, the hydraulic pressure generating means and the electric hydraulic pressure generating means are communicated, and the vehicle is braked by the hydraulic pressure generated by the hydraulic pressure generating means.
According to the vehicle hydraulic pressure generating device of the present invention, in normal use, the hydraulic pressure is generated before the hydraulic pressure generating means generates the hydraulic pressure by detecting the operation amount of the brake pedal by the operating quantity detecting means. Communication between the generating means and the electrical hydraulic pressure generating means can be cut off. As a result, according to this vehicle hydraulic pressure generator, the brake fluid (fluid) is prevented from flowing from the hydraulic pressure generator to the electrical hydraulic pressure generator, and the hydraulic pressure generated by the electrical hydraulic pressure generator is Only by this, the vehicle can be braked more accurately.
Further, according to such a vehicle hydraulic pressure generating device, the hydraulic pressure generating means and the stroke simulator can be communicated with each other before the hydraulic pressure is generated in the hydraulic pressure generating means by the operation amount detecting means. The reaction force based on the hydraulic pressure generated by the pressure generating means can be applied to the brake pedal more quickly without causing the driver to feel a time lag.

In the vehicle hydraulic pressure generator, the spring member may be arranged inside the rear portion of the rear piston member.
According to such a vehicle hydraulic pressure generator, the spring member is accommodated inside the rear portion of the rear piston member, so that the vehicle hydraulic pressure generator can be made more compact. Moreover, in this vehicle hydraulic pressure generator, it is desirable that the rod connecting member as well as the spring member be disposed inside the rear portion of the rear piston member. According to such a vehicle hydraulic pressure generator, the rod member is disposed further inside the rear piston member that moves in the vehicle hydraulic pressure generator, so that the rod connecting member slides in the hydraulic pressure generator. Resistance can be reduced.

Moreover, in this vehicle hydraulic pressure generating device, it is possible to provide a configuration in which a regulating member that contacts the rear end portion of the rod connecting member is provided at the rear end portion of the rear piston member.
In this vehicle hydraulic pressure generating device, the rear piston member moves in the vehicle hydraulic pressure generating device, and the rod connecting member relatively moves in the rear portion of the rear piston member.
At this time, the displacement amount (particularly the return amount) of the rear piston member with respect to the vehicle hydraulic pressure generating device is different from the displacement amount (particularly the return amount) of the rod connecting member with respect to the vehicle hydraulic pressure generating device. The rear piston member includes a restricting member in contact with the rear end portion of the rod connecting member at the rear end portion. Therefore, according to this vehicle hydraulic pressure generator, the initial position can be aligned so that the rear end of the rear piston member and the rear end of the rod connecting member coincide.

  ADVANTAGE OF THE INVENTION According to this invention, the hydraulic generator for vehicles which can be easily assembled | attached to a vehicle body and can reduce an assembly man-hour can be provided.

It is a figure showing arrangement composition in vehicles of a brake system for vehicles provided with a fluid pressure generating device for vehicles concerning an embodiment of the present invention. 1 is a schematic configuration diagram of a vehicle brake system. FIG. 2 is a configuration explanatory diagram of hydraulic pressure generating means (master cylinder) applied to the vehicle hydraulic pressure generating device according to the embodiment of the present invention. FIG. 4 is a partially enlarged view of a portion IV in FIG. 3. It is a configuration explanatory view of a conventional master cylinder.

Embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
The main feature of the hydraulic pressure generator for a vehicle according to the present invention is that it includes hydraulic pressure generating means (master cylinder) having a novel rod connecting member behind the rear piston member. In addition, as described in detail later, the vehicle hydraulic pressure generator according to the present invention includes an electric hydraulic pressure generating means that operates by an electric actuator, a stroke simulator that applies a reaction force to the brake pedal, and an operation amount of the brake pedal. And an operation amount detecting means for detecting.
Below, after describing the vehicle brake system including the vehicle hydraulic pressure generating device according to the present embodiment, the hydraulic pressure generating means (master cylinder) constituting the vehicle hydraulic pressure generating device will be described in more detail.

<Vehicle brake system>
FIG. 1 is a diagram illustrating an arrangement configuration in a vehicle of a vehicle brake system including a vehicle hydraulic pressure generating device according to an embodiment of the present invention. Note that the front, rear, left and right directions of the vehicle V are indicated by arrows in FIG. FIG. 2 is a schematic configuration diagram of the vehicle brake system. The master cylinder and the stroke simulator shown in FIG. 2 are schematically shown for convenience of drawing.

  The vehicle brake system 10 according to 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 having a master cylinder 34 (see FIG. 2) to which a brake operation by an operator (driver) brake pedal 12 (see FIG. 2) is input. A stroke sensor 13 for detecting the operation amount of the brake pedal 12 (see FIG. 2), a motor cylinder device 16 for generating brake fluid pressure based on at least an electric signal corresponding to the operation amount of the brake pedal 12, and a motor cylinder A vehicle stability assist device 18 (hereinafter referred to as VSA device 18; VSA; registered trademark) is provided as a vehicle behavior stabilization device that supports stabilization of the behavior of the vehicle V based on the brake fluid pressure generated by the device 16. ing.
In such a vehicular brake system 10, the vehicular hydraulic pressure generating device 1 according to the present embodiment includes a master cylinder 34 (hydraulic pressure generating means) and a stroke sensor 13 (operating amount detecting means) as shown in FIG. 2. And a motor cylinder device 16 (electrical hydraulic pressure generating means) and a stroke simulator 64 to be described later for applying a brake reaction force to the brake pedal 12.

  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. For example, the motor cylinder device 16 is disposed on the left side in the vehicle width direction opposite to the input device 14 and is attached to a vehicle body such as a 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. These are arranged separately from each other and are connected to each other via 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).

  The hydraulic path will be mainly described with reference to FIG. 2. The connection port 20a of the input device 14 and the connection point A1 are connected by the first piping tube 22a with reference to the connection point A1 in FIG. 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 (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, and the wheels As the hydraulic pressure in the cylinders 32FR, 32RL, 32RR, and 32FL increases, the wheel cylinders 32FR, 32RL, 32RR, and 32FL operate, and the corresponding wheels (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 via two output ports 54a and 54b by a driver's operation of the brake pedal 12, and a first reservoir attached to the master cylinder 34. 36 and a stroke simulator 64. The master cylinder 34 corresponds to “hydraulic pressure generating means” in the claims.
The cylinder tube 38 of the master cylinder 34 is provided with two supply ports 46a and 46b and two relief ports 52a and 52b. 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.
The internal configuration of the master cylinder 34 will be described in detail later.

  The stroke sensor 13 is configured to detect an operation amount of the brake pedal 12, that is, an actual stroke amount (depression amount from the original position) [deg] in the present embodiment. The stroke sensor 13 outputs an operation amount detection signal to a control means such as an ECU (not shown). Incidentally, the control means controls the first shutoff valve 60b (normally open shutoff valve) and the second shutoff valve 60a (normally open shutoff valve) at the timing described later based on the detection signal of the operation amount of the brake pedal 12. The third shut-off valve 62 (normally closed reaction force permission valve) is opened at the timing described later.

A pressure sensor Pm is disposed between the master cylinder 34 and the connection port 20a on the upstream side of the second hydraulic pressure path 58a, and normally open on the downstream side of the second hydraulic pressure path 58a. A second shut-off valve 60a composed of a type (normally open type) solenoid valve is provided.
The second shutoff valve 60a corresponds to a “normally open shutoff valve” in the claims. That is, the master cylinder 34 (hydraulic pressure generating means) can communicate with a motor cylinder device 16 (electrical hydraulic pressure generating device) to be described later via the second shutoff valve 60a (normally open shutoff valve). .
Incidentally, the pressure sensor Pm detects the hydraulic pressure upstream of the second cutoff 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 first shutoff valve 60b corresponds to the “normally shutoff valve” in the claims together with the second shutoff valve 60a. That is, the master cylinder 34 (hydraulic pressure generating means) is connected to a motor cylinder device 16 (electric hydraulic pressure generating device) which will be described later via the second shutoff valve 60a composed of a normally open type (normally open type) solenoid valve. Communication is possible.
Incidentally, the pressure sensor Pp detects the hydraulic pressure on the first hydraulic pressure path 58b on the downstream side of the first shutoff valve 60b (in this embodiment, on the wheel cylinders 32FL, 32RR side as shown in FIG. 2). To do.

  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. In other words, the stroke simulator 64 communicates with the master cylinder 34 (hydraulic pressure generating means) via the third shut-off valve 62, and this normally closed type (normally closed) third shut-off valve 62 is It corresponds to the “normally closed reaction force permission valve” in the range.
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 shown in FIG. 2 applies a reaction force according to the driver's braking operation. In this embodiment, the stroke simulator 64 is integrated with the master cylinder 34 to form the input device 14 shown in FIG. Yes.
It is on the first hydraulic pressure path 58b and is disposed 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.

Next, the motor cylinder device 16 which is an electric hydraulic pressure generating means will be described.
The motor cylinder device 16 is configured to generate a brake hydraulic 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 driving force transmission unit 73 converts a gear mechanism (deceleration mechanism) 78 that transmits the rotational driving force of the motor 72, and converts the rotational driving force into a linear driving force along the axial direction of the ball screw shaft (screw) 80a. And a driving force transmission mechanism 74 including a ball screw structure 80. The driving force transmission mechanism 74, together with the motor 72, constitutes an “electric actuator” in the claims.

  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 body 82, a second slave piston 88a and a first slave piston 88b that are spaced apart from each other by a predetermined distance along the axial direction of the cylinder body 82 are slidably disposed. 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.

  An annular guide piston 230 that provides a fluid-tight seal between the outer peripheral surface of the second slave piston 88a and the driving force transmission mechanism 74 and guides the second slave piston 88a so as to be movable in the axial direction thereof. It arrange | positions so that the outer peripheral surface of 2 slave piston 88a may be opposed. A slave piston packing 90 c is attached to the inner peripheral surface of the guide piston 230. A slave piston packing 90b is mounted on the outer peripheral surface on the front end side of the second slave piston 88a via an annular step. A second back chamber 94a communicating with a reservoir port 92a described later is formed between the slave piston packing 90c and the slave piston packing 90b. A second return spring 96a is disposed between the second slave piston 88a and the first slave piston 88b.

  On the other hand, a pair of slave piston packings 90a and 90b are mounted on the outer peripheral surface of the first slave piston 88b via an annular stepped portion. A first back chamber 94b communicating with a reservoir port 92b described later is formed between the pair of slave piston packings 90a and 90b. A first return spring 96b is disposed between the first slave piston 88b and the front end of the cylinder body 82.

  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.

  A regulating means 100 is provided between the second slave piston 88a and the first slave piston 88b to regulate the maximum and minimum separation distance between the second slave piston 88a and the first slave piston 88b. The first slave piston 88b is provided with a stopper pin 102 that restricts a sliding range of the first slave piston 88b and prevents an overreturn to the second slave piston 88a side. At the time of backup when braking with the brake fluid pressure generated at 34, the failure of another system is prevented when one system fails.

  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.

Note that 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 above-described combination, 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).

<Master cylinder>
Next, the master cylinder 34 as the fluid pressure generating means will be described in more detail. FIG. 3 to be referred to is a configuration explanatory diagram of a master cylinder applied to the vehicle hydraulic pressure generator according to the embodiment of the present invention. FIG. 4 is a partially enlarged view of a portion IV in FIG.

As described above, the master cylinder 34 constitutes the input device 14 together with the stroke simulator 64. Although not shown, the master cylinder 34 is arranged in line with the stroke simulator 64 in the housing of the integrally formed input device 14.
As shown in FIG. 3, in the cylinder tube 38 of the master cylinder 34, a second piston 40a and a first piston 40b that are spaced apart at a predetermined interval along the axial direction of the cylinder tube 38 are slidably disposed. Has been. The first piston 40b corresponds to a “front piston member” in the claims, and the second piston 40a corresponds to a “rear piston member” in the claims.

  The second piston 40a is disposed closer to the brake pedal 12 (see FIG. 2) in the cylinder tube 38. Moreover, the 1st piston 40b is spaced apart from the brake pedal 12 rather than the 2nd piston 40a, and is arrange | positioned ahead of the 2nd piston 40a. In FIG. 3, reference numeral 47 is a restricting means disposed between the first piston 40b and the second piston 40a. The regulating means 47 regulates the minimum separation distance between the first piston 40b and the second piston 40a.

Further, the rear part of the second piston 40a has a cylindrical part 49 that is bottomed at the front end and opens at the rear end.
And in this cylindrical part 49, the rod connection member 43 and the spring member 45 which are mentioned later will be arrange | positioned. The spring member 45 corresponds to “a spring member disposed between the rear piston member and the rod member” in the claims.

  A pair of piston packings 44a and 44b are mounted on the outer peripheral surfaces of the second piston 40a and the first piston 40b via annular stepped portions, respectively. Back chambers 48a and 48b communicating with supply ports 46a and 46b (see FIG. 2) (not shown) are formed between the pair of piston packings 44a and 44b. 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. Has been.

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

  Further, in the cylinder tube 38 of the master cylinder 34, a second pressure chamber 56a and a first pressure chamber for generating a hydraulic pressure (brake hydraulic pressure) corresponding to a pedaling force by which the driver depresses the brake pedal 12 (see FIG. 2). 56b is provided. The second pressure chamber 56a is provided so as to communicate with the connection port 20a (see FIG. 2) via the second hydraulic pressure path 58a (see FIG. 2), and the first pressure chamber 56b is connected to the first hydraulic pressure path 58b. It is provided so as to communicate with another connection port 20b (see FIG. 2) via (see FIG. 2).

The rod connecting member 43 described above is formed of a stepped columnar member having a large diameter cylindrical shape with a front portion having a small diameter cylindrical shape and a rear portion having a diameter larger than that of the front portion.
The rear portion of the large-diameter columnar shape of the rod connecting member 43 has an outer diameter that fits inside the cylindrical portion 49 of the second piston 40a (rear piston member). The rod connecting member 43 in this embodiment is It can slide in the axial direction within the cylindrical portion 49 of the two piston 40a.
And this rod connection member 43 has the fitting hole 43a which receives and fits the spherical front-end | tip part of the push rod 42 in the rear part. Incidentally, the spherical tip end portion of the push rod 42 in the present embodiment is inserted into the fitting hole 43a, and the periphery of the fitting hole 43a is caulked to the spherical tip portion side so that the rear portion of the rod connecting member 43 is inserted. It is supported by.

The spring member 45 is a resilient member and is formed of a coil spring. The spring member 45 is disposed inside the cylindrical portion 49 of the second piston 40a (rear piston member). The rear end of the spring member 45 is supported by the stepped portion of the rod connecting member 43 by inserting the small-diameter cylindrical front portion of the rod connecting member 43 into the rear portion of the spring member 45.
In the master cylinder 34 in the present embodiment, the initial load when the spring member 45 is set is set to be smaller than the initial load when the spring members 50a and 50b are set.
That is, when the rod connecting member 43 is moved forward by the push rod 42, the spring member 45 is contracted in preference to the spring member 50a and the spring member 50b. When restoring, the rod connecting member 43 and the push rod 42 are moved rearward by extending after the spring member 50a and the spring member 50b are extended.

As shown in FIG. 4, the rod connecting member 43 urged rearward by the spring member 45 has a rear end portion in the initial state where no load is input by the push rod 42. It will be located in the vicinity of the rear end of the cylindrical portion 49 of the piston 40a (rear piston member). In other words, the rear end of the rod connecting member 43 urged rearward by the spring member 45 (see FIG. 3) is provided on the inner peripheral surface near the opening of the second piston 40a (cylindrical portion 49). It abuts on the O-ring 49a. The cylindrical portion 49 of the second piston 40 a fitted with the rod connecting member 43 on the inside is positioned by abutting a retaining ring 49 b provided near the opening of the master cylinder 34 at the rear end thereof.
The O-ring 49a corresponds to the “regulating member in contact with the rear end portion of the rod connecting member” in the claims, but the “regulating member” in the present invention is limited to the O-ring 49a. A C-type clip (circular clip, retaining ring) or the like can be used instead. According to such a C-shaped clip, the ease of assembly of the rod connecting member 43 is further improved.
Incidentally, as described above, the input device 14 having such a master cylinder 34 is fixed to the right side in the vehicle width direction of the dashboard 2 (see FIG. 1) via a bolt or the like. The end face of the flange portion on the rear side of the master cylinder 34 shown in FIG. 3 comes into contact with the dashboard 2 (see FIG. 1).

  The vehicle brake system 10 including the vehicle hydraulic pressure generating device 1 according to the present embodiment is basically configured as described above, and the operation thereof will be described next.

When the vehicle brake system 10 functions normally, when the driver inputs a pedaling force to the brake pedal 12 (see FIG. 2), the push rod 42 shown in FIG. 3 presses the rod connecting member 43 forward. To do.
In the master cylinder 34 shown in FIG. 3 in the present embodiment, the rod connecting member 43 resists the reaction force of the spring member 45 while bottoming in the cylindrical portion 49 provided at the rear portion of the second piston 40a. The cylinder portion 49 is advanced until it arrives. At this time, as described above, the spring member 45 contracts preferentially over the spring members 50a and 50b.

  On the other hand, the stroke sensor 13 outputs a detection signal of the operation amount of the brake pedal 12 to a control means (not shown). Based on this detection signal, the control means, after the push rod 42 moves forward, before the rod connecting member 43 settles in the cylindrical portion 49, the first shut-off valve 60b (normally open shut-off valve) and the first shut-off valve A command signal is output so that the second shut-off valve 60a (normally open shut-off valve) is closed and the third shut-off valve 62 (normally closed reaction force permitting valve) is opened. The first shut-off valve 60b and the second shut-off valve 60a receiving the command signal are closed, and the third shut-off valve 62 receiving the command signal is opened.

  As a result, the communication between the master cylinder 34 and the motor cylinder device 16 is disconnected before the master cylinder 34 generates the hydraulic pressure due to the brake operation. Therefore, the brake fluid pressure generated in the master cylinder 34 of the input device 14 is not transmitted to the wheel cylinders 32FR, 32RL, 32RR, 32FL of the disc brake mechanisms 30a-30d.

  The master cylinder 34 and the stroke simulator 64 communicate with each other before the master cylinder 34 generates a hydraulic pressure due to a brake operation. At this time, when the push rod 42 further presses the rod connecting member 43 that has settled in the cylindrical portion 49, the brake hydraulic pressure generated in the first pressure chamber 56b of the master cylinder 34 is divided into the branch hydraulic pressure path 58c and the valve open state. Is transmitted to the hydraulic pressure chamber 65 of the stroke simulator 64 via the third shut-off valve 62 in FIG. When the simulator piston 68 is displaced against the spring force of the first and second return springs 66a and 66b by the brake hydraulic pressure supplied to the hydraulic pressure chamber 65, the stroke of the brake pedal 12 is allowed. The generated pseudo pedal reaction force is applied to the brake pedal 12. As a result, it is possible to obtain a brake feel that is comfortable for the driver.

  In the vehicle brake system 10 according to the present embodiment, when the control means (not shown) detects the depression of the brake pedal 12 by the driver, the motor 72 of the motor cylinder device 16 is driven and the driving force of the motor 72 is increased. 2 is transmitted through the driving force transmission mechanism 74, and the second slave piston 88a and the first slave piston 88b are moved in the direction of the arrow X1 in FIG. 2 against the spring force of the second return spring 96a and the first return spring 96b. Displace towards. 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 vehicular brake system 10 according to the present embodiment, the driver at the normal time when the control means such as the motor cylinder device 16 that is the electric hydraulic pressure generation means and the ECU (not shown) that performs by-wire control can be operated. When the brake pedal 12 is depressed, the communication between the master cylinder 34 that generates brake fluid pressure and the disc brake mechanisms 30a to 30d (wheel cylinders 32FR, 32RL, 32RR, and 32FL) that brake each wheel is communicated with the second cutoff valve 60a. A so-called brake-by-wire brake system in which the disc brake mechanisms 30a to 30d are operated with the brake fluid pressure generated by the motor cylinder device 16 in the state where the first shut-off valve 60b is shut off is activated. 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.

According to the vehicle hydraulic pressure generator 1 that constitutes the vehicle brake system 10 as described above, the following effects can be achieved.
As described above, the vehicle hydraulic pressure generator 1 according to the present embodiment is different from the conventional brake device (see, for example, Patent Document 1), and the push rod 42 of the brake pedal 12 is directly connected to the second piston 40a. Instead of being assembled, the push rod 42 is assembled to the rod coupling member 43 newly provided in the master cylinder 34. A spring member 45 is provided between the rod connecting member 43 and the second piston 40a.
Therefore, according to such a vehicle hydraulic pressure generating device 1, unlike a master cylinder constituting a conventional brake device (see, for example, Patent Document 1), a predetermined amount is provided between the master cylinder 34 and the push rod 42. Since this can be assembled to the vehicle body (for example, the dashboard 2 (see FIG. 1)) without providing the gap α (see FIG. 5), the ease of assembly with respect to the vehicle body is further improved.

  Also, according to the vehicle hydraulic pressure generator 1, unlike the master cylinder (for example, see Patent Document 1) that constitutes a conventional brake device, the master cylinder 34 and the push rod 42 are used when this is attached to the vehicle body. Since there is no need to provide a reaction force spring 245 (see FIG. 5), the assembling man-hour can be reduced.

  Further, according to the vehicle hydraulic pressure generating device 1, unlike a master cylinder (see, for example, Patent Document 1) constituting a conventional brake device, a reaction force spring 245 is provided between the master cylinder 34 and the push rod 42. Since there is no need to provide (see FIG. 5), the vehicle hydraulic pressure generator 1 itself can be made compact.

  In the vehicular hydraulic pressure generating device 1, the rod connecting member 43 is disposed between the second piston 40 a and the push rod 42 of the master cylinder 34, and the second piston 40 a and the rod connecting member 43 are connected to each other. A spring member 45 is disposed therebetween. Accordingly, in the vehicle hydraulic pressure generating device 1, the spring member 45 can apply a reaction force to the push rod 42 even before the rod connecting member 43 is pressed by the push rod 42 and comes into contact with the second piston 40a. it can. As a result, according to the vehicle hydraulic pressure generating device 1, it is possible to reduce the stepped feeling of pedal operation when the driver inputs the pedaling force to the brake pedal 12 to generate the hydraulic pressure in the master cylinder 34. .

Further, according to the vehicle hydraulic pressure generating device 1, the master cylinder 34 (hydraulic pressure generating means) is detected by detecting the operation amount of the brake pedal 12 by the stroke sensor 13 (operating amount detecting means) in normal use. ), The communication between the master cylinder 34 and the motor cylinder device 16 (electrical fluid pressure generating means) can be disconnected before the fluid pressure is generated. As a result, according to the vehicle hydraulic pressure generating device 1, the brake fluid (fluid) is prevented from flowing from the master cylinder 34 to the motor cylinder device 16, and only the hydraulic pressure generated in the motor cylinder device 16 is used for the vehicle. Braking can be performed more accurately.
Further, even after the ignition switch of the vehicle is turned on (IG-ON), before the hydraulic pressure is generated by the master cylinder 34 (hydraulic pressure generating means), it is composed of a normally open type solenoid valve. Since the second shut-off valve 60a and the first shut-off valve 60b can be kept open (because they are not necessarily closed (excited state)), energy saving of the vehicle can be achieved.

  Further, according to such a vehicle hydraulic pressure generating device 1, the master cylinder 34 and the stroke simulator 64 can be communicated with each other before the hydraulic pressure is generated in the master cylinder 34 by the stroke sensor 13. The reaction force based on the hydraulic pressure generated at 34 can be applied to the brake pedal 12 more quickly without causing the driver to feel a time lag.

  Further, according to the vehicle hydraulic pressure generator 1, since the spring member 45 is accommodated in the cylindrical portion 49 at the rear of the second piston 40a (rear piston member), the vehicle hydraulic pressure generator 1 can be made more compact. can do.

  Further, according to the vehicle hydraulic pressure generating device 1, the rod connecting member 43 is disposed further inside (in the cylindrical portion 49) of the second piston 40 a that moves in the master cylinder 34. The sliding resistance of the connecting member 43 can be reduced.

Further, in the present embodiment, on the contrary, it is generated in a conventional master cylinder (see, for example, Patent Document 1) by positively applying a sliding resistance of the rod connecting member 43 in the cylindrical portion 49. It is also possible to suppress the uncomfortable feeling of the brake feel. That is, in the conventional master cylinder shown in FIG. 5, in the return step in which the front piston 240b and the rear piston 240a are retracted, the brake pedal 212 is returned to the stroke initial point only by the reaction force of the reaction spring 245 at the end of the return step. In the section, the sliding resistance of the front piston 240b and the rear piston 240a that occurred in the early stage of the return process (until the front piston 240b and the rear piston 240a completely return to the initial positions) disappears. This makes the brake feel uncomfortable.
On the other hand, in the present embodiment, as described above, it is possible to suppress the uncomfortable feeling of the brake feel at the transition between the early stage and the final stage by positively applying the sliding resistance in the cylindrical portion 49.

  Further, according to the vehicular hydraulic pressure generating device 1, the rear end portion of the second piston 40 a is provided with the restriction member (O-ring 49 a or the like) in contact with the rear end portion of the rod connecting member 43. The initial position can be aligned so that the rear end of the second piston 40a and the rear end of the rod connecting member 43 are aligned with the 34 cylinder tubes 38.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It can implement with a various form.
In the embodiment, the rod connecting member 43 and the spring member 45 are accommodated in the rear portion (in the cylindrical portion 49) of the second piston 40a. However, the rod connecting member 43 and the spring member 45 in the present invention are configured as follows. If it is in the cylinder tube 38, it can be set as the structure arrange | positioned in the back of the 2nd piston 40a.

  Moreover, although the said embodiment assumes the structure which makes the spring constant of the spring member 45 smaller than the spring constant of the spring members 50a and 50b, it shall be equivalent or more with respect to the spring constant of the spring members 50a and 50b. You can also.

DESCRIPTION OF SYMBOLS 1 Vehicle hydraulic pressure generator 12 Brake pedal 13 Stroke sensor (operation amount detection means)
16 Motor cylinder device (electrical fluid pressure generating means)
34 Master cylinder (hydraulic pressure generating means)
40a Second piston (rear piston member)
40b 1st piston (front piston member)
43 Rod connecting member 45 Spring member 49a O-ring (regulating member)
60a Second shutoff valve (shutoff valve)
60b First shutoff valve (shutoff valve)
62 3rd shut-off valve (reaction force permission valve)
64 Stroke simulator 72 Motor (electric actuator)
74 Drive force transmission mechanism (electric actuator)
V vehicle

Claims (4)

Hydraulic pressure generating means for generating hydraulic pressure according to the driver's operation of the brake pedal;
A rear piston member housed in the hydraulic pressure generating means and provided on the brake pedal side;
A front piston member disposed in front of the rear piston member;
In the vehicle hydraulic pressure generator having
A rod connecting member housed inside the hydraulic pressure generating means and connected to the tip of a push rod of the brake pedal;
A spring member disposed between the rear piston member and the rod connecting member;
A vehicular hydraulic pressure generator. The vehicle hydraulic pressure generator according to claim 1,
An electrical hydraulic pressure generating means that is communicated with the hydraulic pressure generating means through a normally open shut-off valve and that is operated by an electric actuator;
A stroke simulator provided via a normally closed reaction force permission valve to communicate with the hydraulic pressure generating means and apply a reaction force to the brake pedal;
An operation amount detection means for detecting an operation amount of the brake pedal,
Before the rod connecting member comes into contact with the rear piston member, the shut-off valve is closed and the reaction force permission valve is opened based on the operation amount of the brake pedal detected by the operation amount detection means. Vehicle hydraulic pressure generator. In the vehicle hydraulic pressure generator according to claim 1 or 2,
The vehicle hydraulic pressure generator according to claim 1, wherein the spring member is disposed inside a rear portion of the rear piston member. In the vehicle hydraulic pressure generator according to claim 3,
A vehicular hydraulic pressure generator comprising a regulating member in contact with a rear end portion of the rod connecting member at a rear end portion of the rear piston member.

Images