JP2008254586A - Vehicular brake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-hydraulic type vehicular brake device which is provided with a master cylinder connected to a wheel brake, a motor, a ball screw mechanism and a stroke simulator, simple in structure and highly reliable, and favorable for a cooperative regenerative brake. <P>SOLUTION: The vehicular brake device has a ball screw mechanism for converting the turn of a nut connected to a motor which is regulated in an advancing/retracting manner and turnably retracting manner to the straight motion of a bolt whose turn is regulated. A fore end of the bolt is connected to a master cylinder, and an input transmission member having a stroke simulator is opposed to a rear end of the bolt. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes a brake operator, a ball screw linear motion mechanism that is linked to a motor that can freely rotate in the forward and reverse directions, and a master cylinder that is capable of transmitting the thrust of the ball screw linear motion mechanism to a master piston and is connected to a wheel brake. The present invention relates to a vehicle brake device.

Conventionally, such a brake device for a vehicle is already known from, for example, Patent Document 1, Patent Document 2, and Patent Document 3.
Japanese Patent Publication No. 6-9964 Japanese Patent No. 3605460 JP 2007-15547 A

  In the above-mentioned Patent Document 1, one end of a bolt of a ball screw linear motion mechanism whose rotation is restricted is in contact with a master piston, and the other end is connected to a brake pedal. An electric brake booster is disclosed in which a bolt advances and retreats in the direction of the rotation axis by the rotation of a rotor and a nut whose positions are restricted.

  However, in the above disclosed example, when the brake pedal is depressed when the rotation of the motor becomes free, the master piston cannot be pushed unless the nut is rotated as the bolt advances.

  In general, the ball screw has high reverse efficiency when the nut is rotated by pushing the bolt, but the lead is set small to rotate the nut with high inertial force and the rotating body on which the motor cogging torque is applied. In order to move, a large pressing force is required, so that the pedal operation force transmitted to the master piston is greatly lost.

  Furthermore, if the motor rotor is stuck, the operating force of the brake pedal cannot be transmitted to the master piston, and there remains a problem in failsafe.

  Since the brake pedal is connected to the bolt so as not to be separated, the brake pedal also enters as the bolt automatically advances when the automatic brake operation is performed, which causes the driver to feel uncomfortable. Become.

  In Patent Document 2, a bar-shaped pushing member connected to a bolt, which is a linear motion member of a ball screw linear motion mechanism driven by a motor in parallel with the master cylinder axis, pushes the master piston from behind. In addition, there is disclosed a vehicle brake device including assist force applying means configured such that an input rod tip connected to a brake pedal penetrates the bar-like pushing member and can push the master piston.

  With the assist force applying means configured as described above, the operation force loss when the motor becomes free, which is the subject of Patent Document 1, is large, and the master cylinder cannot be operated when the motor is fixed. The input rod penetrating the member without interference is solved because the master piston can be pushed directly.

  However, since the ball cylinder linear motion mechanism configured by offsetting the axis in parallel is supported by the master cylinder hydraulic pressure reaction force generated at a maximum of about 10000 N, the rigidity of the bar-shaped pushing member and the master cylinder and the ball screw Problems remain such as an increase in weight to increase the mutual attachment rigidity with the moving mechanism, and a decrease in efficiency and durability due to a bias load exerted on the ball and nut by the bar-shaped pushing member that is cantilevered.

  In addition, when automatic brake operation control that generates brake fluid pressure is performed regardless of whether or not the brake operation member is input, and the brake pedal is operated during the control, the input is in the backward limit with the master piston that is moving forward A so-called idling of the brake pedal occurs at the saddle.

  Furthermore, when control is performed to weaken the assist force in coordination with the electric regenerative brake, the amount of advance of the master cylinder piston decreases, so the amount of brake pedal operation (stroke relative to input) is less than the vehicle braking force. Will be less.

  In other words, since the stroke of the brake operation member during automatic braking and regenerative cooperative brake control is different from that during normal assist, there is a discrepancy between the input by the driver's learning and the relationship between the stroke and the generated deceleration. It will make you feel uncomfortable.

  In Patent Document 3, a bolt is connected to a brake pedal, the retraction limit and rotation of the bolt are restricted, and the nut is moved forward and backward while rotating so that the master piston can be pushed forward. A vehicular brake hydraulic pressure control device including a mechanism is disclosed.

  When the solenoid valve in the pipe is closed, a stroke simulating operation is performed so that the nut in the backward limit draws the brake pedal in the nut direction.

  In addition, when the solenoid valve in the pipe is open, the brake pedal regulates the backward movement limit of the bolt so that the nut moves forward and backward to push the master piston.

  When the master piston is mechanically pushed directly only by the operating force of the brake pedal, the nut is rotated by the push of the bolt and the master piston cannot be pushed only by the proximity of the brake pedal and the nut. In order to prevent the rotation of the motor and the nut, a holding force is applied to the motor, or a ball screw that cannot rotate the nut by pushing the bolt is used.

  However, in the apparatus configured as described above, when the nut and the master piston are moved forward and backward by the rotation of the motor, when the driver operates the brake pedal that receives the high hydraulic reaction force of the master cylinder, the feeling of depression is felt. There is no good feeling at all.

  That is, the operation of the master cylinder by the rotation of the motor, the stroke simulating operation, and the natural stroke operation of the brake pedal cannot be linked.

  Also, when the master piston is pushed only by the operating force of the brake pedal, the rotation of the motor is held to stop the rotation of the nut so that the relative position of the bolt and the nut does not change as described above. However, this operation mode should be used frequently when the motor has some trouble and the motor cannot be controlled. When the motor becomes free, the master piston cannot be pushed. .

  On the other hand, the ball screw that cannot rotate the nut by the pushing of the bolt can increase the turning torque against the pushing load if the lead is made small. There is a problem.

  The present invention has been made in view of such circumstances, and has a ball screw linear motion mechanism that has a simple configuration and can efficiently convert the brake operator input of the driver. An object of the present invention is to provide an electrohydraulic vehicle brake device that is suitable for cooperative regenerative braking and automatic braking at low cost.

  In order to achieve the above-mentioned object, the invention according to claim 1 converts the forward and reverse rotation of the motor and the rotation of the nut interlocking with the motor into the linear movement of the bolt whose rotation is restricted in the axial direction. A ball screw linear motion mechanism, a brake operator linked to the rear end of the bolt so as to be able to push the bolt, and a front end of the bolt at the rear end of the master piston that faces the hydraulic chamber to which the wheel brake is connected. A brake device for a vehicle including a master cylinder linked to the nut, and the nut constituting the ball screw linear motion mechanism is capable of advancing and retracting in an axial direction and is restricted to a retractable limit by a housing. A brake device for a vehicle is used.

  According to a second aspect of the present invention, in addition to the first aspect of the invention, a nut constituting the ball screw linear motion mechanism and the motor are arranged coaxially, and a rotating member of the motor is provided as a housing. The rotor is constrained to move back and forth in the axial direction and is pivotally supported on the rotor so that the nut can be continuously rotated, and the forward and backward movement in the axial direction can be enabled. To do.

  According to a third aspect of the present invention, in addition to the first aspect of the present invention, the housing is engaged with a rotating drive gear shaft provided in the motor, and the housing is restrained from moving back and forth in the axial direction and is freely rotatable. The nut can be continuously rotated with respect to the driven gear shaft that is pivotally supported on the shaft, and can be moved back and forth in the axial direction.

  According to a fourth aspect of the invention, in addition to the third aspect of the invention, the drive gear shaft is a worm gear, and the driven gear shaft is a worm wheel gear.

  According to a fifth aspect of the present invention, in addition to the first aspect of the present invention, the front end of the bolt faces the rear end of the bolt so that the bolt can be pushed, and the rear end is connected to the brake operator. And a stroke simulator capable of shortening the relative distance between the input transmission member and the nut corresponding to the input of the brake operator.

  According to a sixth aspect of the invention, in addition to the fifth aspect of the invention, the stroke simulator has a cylindrical elastic member provided on the outer periphery of the bolt, and the elastic member is connected to the nut and the input transmission. The elastic member and the input transmission member are connected to the nut so as to be capable of advancing and retracting in the axial direction.

  The invention according to claim 7 is characterized in that, in addition to the invention according to claim 5 or 6, the input transmission member, the bolt, and the master piston are arranged coaxially.

  The invention according to claim 8 includes, in addition to the invention according to any one of claims 5 to 7, an input detector and an electronic control device, and at least the advance of the input transmission member transmitted from the brake operator. The power of the motor is controlled so as to prevent advance of the nut from the retreat limit due to thrust, and the advance distance of the input transmission member is made smaller than the advance distance of the bolt with respect to the nut being controlled. And setting the rigidity of the stroke simulator.

  The invention according to claim 9 includes, in addition to the invention according to any one of claims 5 to 7, an input detector and an electronic control unit, and at least the advance of the input transmission member transmitted from the brake operator. The stroke simulator is configured to control the power of the motor so as to prevent the nut from moving forward due to thrust, and to allow the front end of the input transmission member to push the rear end of the bolt under control. It is characterized by setting rigidity.

  According to the first aspect of the present invention, the nut connected to the rotation of the motor is restricted to the retreat limit and is turned, and the thrust of the bolt that is the linear motion member is controlled by the reaction force restricted by the retreat limit. It is possible to increase the pressure of the master cylinder by transmitting it to the piston and to add the input of the brake operator linked to the rear end of the bolt to the bolt.

  In the unlikely event that the motor becomes free due to motor control failure, etc., if the nut is constrained in the axial direction, the rotation of the nut by pushing the bolt becomes indispensable. This is required for a brake operator that cooperates with an additional bolt pushing force to overcome the motor cogging torque and turn the nut.

  However, in the present invention, since the nut can be moved back and forth in the axial direction, it is not necessary to rotate the nut as the bolt is pushed, and the input of the brake operator can be transmitted to the bolt and the master piston without loss. The master cylinder can be boosted with extremely high efficiency.

  In addition, even if the motor is locked and cannot rotate, the thrust of the bolt due to the depression of the brake operator is transmitted to the master piston without loss due to the forward and backward movement of the nut, and the master cylinder is boosted with extremely high efficiency. can do.

  According to the second aspect of the present invention, the rotation of the motor is transmitted because only the rotor and the nut, which are rotating members of the motor, can be used to freely rotate the nut and restrict the retreat limit and to be able to move forward and backward in the axial direction. Therefore, it is not necessary to provide a gear or the like, and the inertial force applied to the rotational force of the motor can be reduced to obtain a high hydraulic pressure response of the master cylinder.

  A layout is also possible in which the bolt is passed through the motor in the direction of the rotation axis so that the bolt moves forward and backward with respect to the motor. A brake operator is linked to one end of the motor in the axial direction and the master is connected to the other end. Cylinders can be arranged, and the ball screw linear motion mechanism and motor housing can be shared (and also with the master body), improving packaging efficiency, reducing the number of parts, and reducing costs. Can be planned.

  According to the invention of claim 3, since the reduction gear ratio can be arbitrarily set for the drive gear shaft connected to the motor and the driven gear shaft for rotating the nut, the setting of the lead of the ball screw mechanism becomes easy. Also, it is possible to use a general-purpose automobile motor without necessarily designing the motor.

  According to the invention of claim 4, when the worm wheel gear is driven and the worm wheel gear is driven, the power transmission positive efficiency is good, but conversely the worm wheel gear is driven and the worm gear is driven. Since the power transmission reverse efficiency is extremely low, the load torque transmitted back to the motor is small even when a high load is applied to the ball screw linear motion mechanism while maintaining the high pressure of the master cylinder. Can be omitted.

  Also, if the master cylinder is boosted by the high power of the motor, even if the motor power suddenly expires, the existing hydraulic pressure reaction force tries to push back the bolt and interlocks with the nut in the backward limit. When reverse rotation is attempted, the reverse efficiency when transmitting from the worm wheel gear to the worm gear is low, so resistance to the reverse rotation of the nut is applied, and the reduction of the master cylinder hydraulic pressure and braking force is delayed in conjunction with the backward movement of the bolt. On the other hand, the force that pushes the bolt by the input of the brake operator is transmitted to the master cylinder with high efficiency without the need for rotation of the nut that accompanies the push of the bolt. .

  In other words, because the nut can be moved back and forth in the axial direction, even if a worm and worm wheel gear pair is used for power transmission of the nut, the master cylinder hydraulic pressure boosted by the motor power is unlikely to decrease. The additional boosting of the master cylinder by the brake operator can be performed very efficiently. If the worm and worm wheel gear pair is like a hydraulic circuit, an orifice is provided in parallel between the master cylinder and the wheel brake, and the wheel brake side It can act like a one-way valve that opens.

  According to the fifth aspect of the present invention, when the nut is in the retreat limit due to the rotation of the motor, and the bolt is advanced and retracted to push the master piston and pressurize the master cylinder, the rigidity of the stroke simulator is arbitrarily set. It is possible to set the feel of the operation of the brake operator freely.

  When the amount of shortening of the relative distance between the nut and the input transmission member is set smaller than the amount of bolt advancement relative to the nut, that is, when setting the rigidity of the stroke simulator so that the front end of the input transmission member does not contact the rear end of the bolt Although the thrust of the input transmission member is not transmitted to the bolt and the master piston, it is possible to reduce the driving load by reducing the brake operation stroke of the driver.

  Also, when the rigidity of the stroke simulator is set so that the front end of the input transmission member contacts the rear end of the bolt and pushes the bolt in cooperation with the motor power, the movement distance of the input transmission member is the master piston movement distance. However, since the thrust of the input transmission member is transmitted to the bolt that is in contact with the master piston, the power consumption of the motor can be saved, or the power consumption of the motor can be maintained and the master cylinder pressure can be further increased.

  If there is no rotation of the motor and the master piston is pushed by the thrust of the input transmission member by the brake operator input, the distance between the front end of the input transmission member and the rear end of the bolt that is set in the initial non-operational state When the input transmission member strokes only (the distance may be zero), the thrust of the input transmission member is transmitted to the bolt and pushes the master piston, minimizing the stroke loss of the brake operator. Cylinder pressure can be increased.

  In this way, an arbitrary brake operation feeling can be set, and the driver can step on the brake operator firmly without being panicked by a deep depression of the brake operator in the event of a motor failure.

  According to the sixth aspect of the present invention, when the bolt is pushed by the brake operation element input without the motor power, the reaction force of the stroke simulator transmitted to the brake operation element is the front end of the input transmission member in the non-operation initial state. The distance between the bolt and the rear end of the bolt (the distance may be zero) × the spring constant of the elastic member is added, but the elastic member and the input transmission member move forward (ie, the nut) Therefore, this reaction force is also transmitted to the bolt via the nut and becomes a master piston pushing force, so there is no loss.

  If the front end of the elastic member abuts the housing in parallel and the forward limit is fixed, the amount of movement of the nut and the input transmission member x the spring constant of the elastic member is added to the input transmission member. In order to obtain a predetermined braking force without transmitting the reaction force as an acting force to the master piston, it is necessary to input a large brake operator. In the present invention, the elastic member and the nut are connected to the nut as described above. Since the input transmission member moves back and forth, the thrust of the input transmission member transmitted from the brake operator is transmitted to the master piston effectively and the master cylinder is boosted.

  According to the seventh aspect of the present invention, since the input transmission member constituting the stroke simulator, the bolt constituting the ball screw, and the master piston provided in the master cylinder are arranged coaxially, the input provided in the ball screw and the stroke simulator. The transmission member supports the hydraulic reaction force generated by the master piston, which is about 10000 N at the maximum, coaxially and in series so that the three members can efficiently perform input / output conversion without receiving an offset load.

  And since a housing can also be designed without considering bending rigidity, a brake hydraulic-pressure generator can be comprised lightweight and compactly.

  According to the eighth aspect of the present invention, since the stroke of the bolt and the master piston and the stroke of the input transmission member can be separated, the master cylinder diameter is obtained in order to obtain a sufficient braking force with a small stepping force in case of a motor failure. The brake actuator's input load x stroke, which is the work load of the driver, during normal pressure-increasing brake operation control while increasing the degree of freedom of setting such as the hydraulic ratio to make the diameter smaller, the lever ratio of the brake operator to make it larger in advance Can be reduced.

  Also, cooperative regenerative braking control is performed, and the motor piston power is controlled to reduce the master cylinder hydraulic pressure so that the wheel brake braking force is obtained by subtracting the regenerative braking force from the vehicle braking force desired by the driver. If the bolt rear end and the input transmission member front end are set apart from each other in advance by a predetermined amount, the brake operator input operated by the driver, the brake operator stroke, the vehicle control The relationship with power can always be constant.

  In addition, since the ball screw linear motion mechanism, which is the output control target of the electronic control device, and the input transmission member make a stroke away from each other, the control source of the electronic control device does not necessarily require the brake operation load detection value, It is also possible to use only the child stroke value.

  According to the ninth aspect of the present invention, a part of the thrust of the input transmission member is used by the stroke simulator to produce a pseudo load reaction force, and the remaining thrust is supplied by the motor torque to push the master piston. It is transmitted to the moving bolt rear end.

  The thrust transmitted to the rear end of the bolt works so as to reduce the load of the rotational force that causes the motor to advance the bolt via the nut. Therefore, the power transmitted to the rear end of the bolt can be saved, or the power and power consumption of the motor can be saved. And higher master cylinder pressure can be increased.

  On the other hand, the thrust used for the stroke simulator to produce a pseudo load reaction force is transmitted to the brake operator as a reaction force.

  It is preferable that the reaction force of the brake operator has a moderate repulsion, but if the brake operator is directly connected to the rear end of the bolt, the bolt that is predominantly pushed by the motor The reaction force transmitted to the operation brake operator lacks a sense of repulsion.

  The input transmission member that abuts against the bolt rear end so as to be separable and pushes the bolt is applied with the reaction force of the bolt and the reaction force of the stroke simulator in parallel, and the brake feeling is set by the stroke simulator. Can be transmitted to the child.

  Thus, the rigidity of the stroke simulator is set so that the bolt can be pushed by the input transmission member, thereby reducing the load on the motor or increasing the pressure of the master cylinder and applying the reaction force applied to the brake operator to the bolt. This is a hybrid of the reaction force that pushes and the pseudo reaction force of the stroke simulator.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 8 show a first embodiment of the present invention. FIG. 1 is a brake hydraulic system diagram showing the overall configuration of a vehicle brake device. FIG. 2 is a non-operation initial position of the brake hydraulic pressure generator. FIG. 3 is a cross-sectional view of the main part of the left side of the brake fluid pressure generator at the initial non-operation position, and FIG. 4 is a left side of the brake hydraulic pressure generator at the pressure-increasing brake operating position. FIG. 5 is an enlarged cross-sectional view of the main part of the left side of the brake fluid pressure generating device at the non-intensifying brake operating position, and FIG. 6 is a cross-sectional view taken along line 1-1 and 2-2 in FIG. 7 is a stroke simulator characteristic diagram, and FIG. 8 is an output hydraulic pressure characteristic diagram.

  First, in FIG. 1, a brake fluid pressure generating device 10 includes a ball screw linear motion mechanism 90 equipped with a motor 110 on the outer periphery, and an input connected to a brake operation element 11 which is a brake operation member at the rear of the ball screw linear motion mechanism 90. Means 30 and a tandem type master cylinder 60 mounted on the upper portion with a master reservoir 12 made of resin or the like and storing brake fluid are provided at the front of the ball screw linear motion mechanism 90.

  The electronic control device 13 is a small-sized power source 8 and stores power sufficient for the electronic control device 13 to perform several times of pressure-increasing brake operation control of the brake fluid pressure generating device 10 when a failure occurs in the power supply 8. Connected to the capacitor 9, the vehicle brake device can be controlled in an integrated manner.

  The operation amount of the brake operation element 11 is detected by an input detector A25 configured by an encoder, a potentiometer or the like and detecting an operation stroke, and an input detector B26 configured by a strain sensor or the like and detected by an operation load. The value is transmitted to the electronic control device 13, and the electronic control device 13 controls the power of the motor 110 provided in the brake fluid pressure generating device 10 based on the detected value.

  Furthermore, the detected value of the output detector 27 that detects the pressure generated by the master cylinder 60 and the detected current value of the motor 110 are also transmitted to the electronic control device 13, and the brake fluid pressure generating device 10 is provided based on these values. Feedback control of the power of the motor 110 is made possible.

  Further, the electronic control device 13 controls the brake fluid pressure generating device 10 and the ABS 15 described below based on the detected values of a wheel speed sensor, a yaw sensor, a G sensor, etc. (not shown) to perform integrated control of the vehicle. Allows for the wiring of electrical circuits. And the alarm device 14 which issues a warning to a driver at the time of abnormality of these vehicle brake devices is provided.

  The hydraulic pressure output from the front output port 16F and the rear output port 16R of the master cylinder 60 is guided to the front hydraulic pressure path 17F and the rear hydraulic pressure path 17R, and the generated hydraulic pressure in the rear hydraulic pressure path 17R is a pressure sensor. It can be detected by an output detector 27 constituted by

  The front hydraulic pressure path 17F is connected to the left front wheel brake BFL and the right front wheel brake BFR via the ABS 15. The rear hydraulic pressure path 17R is also connected to the left rear wheel brake BRL and the right rear wheel brake BRR via the ABS 15.

  The ABS 15 branches to the front hydraulic pressure passage 17F and is connected to a normally open solenoid valve 18, 18 and a normally open solenoid valve 18, 18 provided between the left front wheel brake BFL and the right front wheel brake BFR. One-way valves 19 and 19 connected in parallel, a pressure reducing reservoir 21, a left front wheel brake BFL, a right front wheel brake BFR and a normally closed solenoid valve 20 provided between the pressure reducing reservoir 21, a pressure reducing An ABS pump 23 driven by an ABS motor 22 is provided to recirculate the brake fluid from the reservoir 21 to the front hydraulic pressure path 17F side.

  Further, the ABS 15 branches the rear hydraulic pressure path 17R, and a normally open solenoid valve 18, 18 provided between the left rear wheel brake BRL and the right rear wheel brake BRR, and a normally open solenoid valve 18, 18, one-way valves 19 and 19 connected in parallel, a pressure reducing reservoir 21, a left rear wheel brake BRL, a right rear wheel brake BRR and a normally closed solenoid valve 20 provided between the pressure reducing reservoir 21, 20 and an ABS pump 23 driven by an ABS motor 22 in order to return the brake fluid from the decompression reservoir 21 to the rear hydraulic pressure passage 17R side.

  The ABS 15 is controlled by the electronic control unit 13, and the normally open solenoid valve 18 that opens the normally open solenoid valve 18 and closes the normally closed solenoid valve 20 corresponding to each wheel brake BFL, BFR, BRL, BRR, and the normally open solenoid valve. The pressure reducing mode in which the normally closed solenoid valve 20 is closed and the normally open solenoid valve 18 and the normally closed solenoid valve 20 are both closed and controlled in a closed mode, thereby controlling the wheel brakes BFL, BFR, The brake fluid pressure of BRL and BRR can be optimally controlled individually according to the situation.

  The electronic control unit 13 controls the brake fluid pressure generating device 10 and the ABS 15 in an integrated manner. The brake fluid pressure generating device 10 increases brake operation control and anti-lock according to the operation amount of the brake operator 11. Brake control, automatic brake control that automatically generates the hydraulic pressure in the brake hydraulic pressure generator 10 regardless of whether or not the brake operator 11 is operated, and further, the ABS 15 is controlled from the automatic brake control to optimize the individual wheel brake hydraulic pressure. Traction control and vehicle stability control can be performed.

  Further, the electronic control unit 13 can cope with cooperation with an electric regenerative braking device (not shown), and the wheel brake braking force obtained by subtracting the braking force of the electric regenerative braking device from the vehicle braking force desired by the driver. In this way, the brake fluid pressure generating device 10 can be controlled to increase pressure braking.

  In FIG. 2, the brake hydraulic pressure generating device 10 which is the initial non-operation position includes a ball screw linear motion mechanism 90 equipped with a motor 110 on the outer periphery, a master cylinder 60 at the front of the ball screw linear motion mechanism 90, The input means 30 is connected to the rear part of the ball screw linear movement mechanism 90.

  The master cylinder 60 connects the flange portion of the master body 61 to the housing D92 of the ball screw linear motion mechanism 90, and the ball R-shaped front end of the bolt 100 protruding from the ball screw linear motion mechanism 90 is connected to the rear master piston 62. The rear sphere R-shaped bottom is coaxially abutted.

  The master cylinder 60 is of a tandem type, and includes a front hydraulic chamber FPL that generates hydraulic pressure as the front master piston 68 advances, and a rear hydraulic chamber RPL that generates hydraulic pressure as the rear master piston 62 advances. And define.

  In the master body 61, front and rear master pistons 68 and 62 are slidably inserted into a bottomed cylindrical cylinder inner diameter 61a.

  A master reservoir 12 (see FIG. 1) made of synthetic resin is attached to the upper portion of the master body 61 so as to be able to replenish the brake fluid into the cylinder of the master body 61, and fills the brake fluid.

  A replenishment port FSP that opens to the axially intermediate portion of the front master piston 68 is provided between the intermediate portion of the front master piston 68 and the cylinder of the master body 61 so as to constantly supply brake fluid. Is drilled.

  A cup 69 slidably in contact with the cylinder inner diameter 61a is attached to the front portion of the front master piston 68 in order to generate a hydraulic pressure in the front hydraulic chamber FPL. Further, a cup 70 slidably contacting the cylinder inner diameter 61a is mounted on the rear side of the front master piston 68 so as to receive the hydraulic pressure generated in the rear hydraulic pressure chamber RPL.

  The front master piston 68 is provided with a central relief valve 71 that allows the front hydraulic pressure chamber FPL and the master reservoir 12 to communicate with each other when the front master piston 68 returns to the retreat limit position by the biasing force of the return spring 73. It is done. The relief valve 71 is coaxially mounted on the front end valve box of the front master piston 68. When the front master piston 68 is in the retreat limit, the relief valve 71 is moved forward against the spring biasing force of the valve spring 72. The valve is opened and the both ends of the front master piston 68 are fixedly supported by the master body 61 so as to allow the valve spring 72 to move backward, that is, to close the valve when the front master piston 68 moves forward. The bar 74 is configured to be openable and closable.

  Both ends of the valve opening rod 74 are supported by the master body 61 and are inserted into the long holes 68 a of the front master piston 68, and the rear end of the relief valve 71 is brought into contact with the valve opening rod 74.

  When the front master piston 68 is in the retreat limit, the relief valve 71 is opened when the relief valve 71 is pressed by the valve opening rod 74, and the front hydraulic chamber FPL and the master reservoir 12 are communicated with each other. The brake fluid can be refilled inside. When the front master piston 68 moves forward from the retreat limit, the valve opening rod 74 moves rearward relative to the front master piston 68, whereby the relief valve 71 is closed and the pressure in the front hydraulic chamber FPL is reached. Can be generated.

  The rear master piston 62 is in contact with the front end of the spline guide 75 at the rear end, and the rear end of the spline guide 75 is in contact with the retaining ring 76 to restrict the backward limit of the spline guide 75 together with the rear master piston 62.

  The rear master piston 62 is slidably contacted with the cylinder inner diameter 61a on the rear outer periphery of the rear master piston 62, and the cup 63 is slidably contacted with the cylinder inner diameter 61a while allowing the brake fluid to flow only from the rear on the front outer periphery. A cup 64.

  The master body 61 communicates with the master reservoir 12 and the rear hydraulic chamber RPL when the rear master piston 62 is in the retreat limit position, and with the master reservoir 12 by the passage of the cup 63 at the forward position of the rear master piston 62. A relief port RP that closes and closes the communication of the rear hydraulic chamber RPL and a replenishment port RSP that constantly replenishes brake fluid from the master reservoir 12 to the cup 63 and the cup 64 are provided.

  In order to regulate the maximum distance between the front and rear master pistons 68 and 62, the set length of the retainer 65 that contacts the rear end of the front master piston 68 and the return spring 66 that is contracted between the rear master piston 62 is set as the rear master piston. A retainer guide 67 screwed onto the piston 62 is regulated.

  The set load of the return spring 66 of the rear master piston 62 is set larger than the return spring 73 of the front master piston 68, and the maximum distance between the front and rear master pistons 68, 62 is set at the rearward limit of the rear master piston 62. The backward limit of the front master piston 68 is also set at the position where is set.

  In the master cylinder 60 configured as described above, when the rear master piston 62 is pushed, first, the rear master piston 62 and the front master piston 68 start to advance simultaneously and are set smaller than the return spring 66 of the rear master piston 62. The return spring 73 of the front master piston 68 set to the load is bent.

  The relief valve 71 in the front master piston 68 and the relief port RP in the rear master piston 62 close at the same time.

  After the valve closing operation, the front master piston 68 floats so that the rear hydraulic chamber RPL and the front hydraulic chamber FPL have the same pressure in accordance with the forward and backward movement of the rear master piston 62, and the rear master piston 62 The hydraulic pressure is supplied to the wheel brakes BFL, BFR, BRL, and BRR while adjusting the relative distance between them.

  When the rear master piston 62 and the front master piston 68 return to the retreat limit, the relief valve 71 is opened in the front master piston 68, and the relief port RP is opened in the rear master piston 62, and the rear hydraulic chamber RPL and the front liquid are opened. The pressure chamber FPL communicates with the master reservoir 12 to be in an atmospheric pressure release state.

  Referring also to FIG. 3, the input means 30 connects the flange portion of the housing A31 to the housing B91 of the ball screw linear movement mechanism 90, and the rear end of the flange portion is attached to the vehicle body.

  A substantially cylindrical sleeve 36 is inserted into the inner diameter portion of the housing A31 at the bottom of the cylinder through a bolt 100 provided in the ball screw linear movement mechanism 90 and is slidably inserted into the inner diameter of the housing A31. The limit of retreat is restricted by the locking ring 40 fitted in the groove at the rear of the inner diameter, and the front end step portion 36a faces the thrust bearing 98 provided in the ball screw linear motion mechanism 90.

  The input transmission member 35 has a push rod 33 connected to the central portion of the rear end 35c so as to be swingable. The push rod is screwed together with a fastening screw 34 to a yoke 32 connected to the brake operator 11 (FIG. 1). The

  The shaft portion of the input transmission member 35 is slidably inserted into the inner diameter portion of the sleeve 36, and the retreat limit is restricted by a locking ring 41 fitted in the groove portion at the rear portion of the inner diameter of the sleeve 36. 35a faces the rear end 100d of the bolt 100 provided in the ball screw linear movement mechanism 90 coaxially with a separation distance L3.

  In response to an input to the brake operator 11 of the driver, a reaction force and a stroke are applied to the brake operator 11 between the front step portion 35b of the input transmission member 35 and the first step portion 36b of the sleeve 36. Constitutes a stroke simulator SS.

  In the stroke simulator SS, the retainer 37 has an outer diameter that can slide on the sleeve 36 and an inner diameter that can slide on the small-diameter shaft of the input transmission member 35. Further, the ball screw linear motion mechanism 90 is provided on the sleeve 36 bottom inner diameter 36d and the retainer 37 inner diameter 37d. The bolt 100 provided in is inserted without interference.

  A simulated spring 38 that is a winding spring is stretched between the front step portion 37 a of the retainer 37 and the first step portion 36 b of the sleeve 36, and the rear step portion 37 b of the retainer 37 and the front step portion of the input transmission member 35. A simulation rubber 39 made of an elastic material such as rubber is stretched between 35b.

  The retainer 37 is in a position where the loads of the simulated spring 38 and the simulated traverse 39 are balanced, and the front step portion 37a of the retainer 37 and the second step portion 36c of the sleeve have a separation distance L1, and the rear end 37c of the retainer 37 and the input transmission. The front step portion 35b of the member 35 has a separation distance L2.

  The total stroke of the input transmission member 35 set in the stroke simulator SS is a separation distance L1 + L2, and the separation distance L1 + L2 is set so as not to exceed the allowable stress of the simulation spring 38 and the simulation traverse 39.

  However, in the stroke simulator SS when the ball screw linear motion mechanism 90 is in the non-operation initial position as shown in FIG. 3, only the separation distance L3 between the rear end 100d of the bolt 100 and the front end 35a of the input transmission member 35 It only allows advancement.

  The ball screw linear motion mechanism 90 is configured in the same body as the motor 110, and sandwiches a housing C111 in which a cylindrical stator 112 and a plurality of spring seats 115 are fixed to an inner peripheral wall, and a plurality of (FIG. 1) tie bolts 93. Thus, the housing B91 and the housing D92 are screwed to both ends of the tie bolt 93 so that the fastening female screws 94 are increased in rigidity of the housing.

  A coil 113 wound around the outer periphery of the rotor 113 is provided on a rotor 113 that is supported by a radial bearing 95, 95 sandwiched between the housing B 91 and the housing D 92 so as to be restrained from advancing and retreating in the axial direction and pivotally supported. A cylindrical commutator 118 connected to the outer periphery of the rotor 113 is fitted, and the outer periphery of the rotor 113 and the inner periphery of the stator fixed to the housing C have a predetermined air gap.

  A conductive brush spring 115 is stretched between the brush and a spring seat 115 fixed to the housing C so that the brush 117 elastically contacts the outer periphery of the commutator 118, and the electronic control device 13 (see FIG. The control current from 1) is derived and forward / reverse control of the rotor 113 is performed.

  On the inner periphery of the rotor 113, the nut 113, which is a pair of ball screws and the rotor 113, is allowed to rotate so that the nut 96 is connected to the rotor 113 by a sliding spline, and the nut 96 is axially moved on the inner periphery of the rotor 113. It is possible to move forward and backward.

  Referring to the cross section taken along line 1-1 in FIG. 1, the sliding spline has a small number of female splines 113 a formed on the inner periphery of the rotor 113 and a plurality of male splines 96 b formed on the outer periphery of the nut 96. It is inserted so as to be able to move forward and backward while restricting relative rotation with a gap (allowing continuous rotation).

  Returning to FIG. 3, the nut 96 constitutes a thrust bearing 98 at the rear portion, and the ball 97 rolls to bring the rear end 98 a of the thrust bearing 98 into contact with the bottom portion 91 a of the housing B 91, so that the nut 96 is connected to the rotor 113. Can be freely rotated and the retreat limit is regulated.

  A bolt 100 that is a pair of ball screws passes through the inner periphery of the nut 96, and a ball 99 that is rotatably inserted in an external thread groove 100 a on the outer periphery of the bolt 100 and an internal thread groove 96 a on the inner periphery of the nut 96. Therefore, the ball screw is configured so that the relative spiral rotation between the bolt 100 and the nut 96 can be smoothly performed.

  Referring to the section 2-2 in FIG. 1 of FIG. 6, the bolt 100 is restricted from rotating in the hydraulic pressure generator 10, and the male spline 100b formed on the front outer periphery of the bolt 100 is a master. A plurality of female splines 75a formed in a spline guide 75 that is fitted with a pair of rotation stoppers 75b on the rear portion of the body 61 and restricted in rotation are inserted with a slight gap so that the sliding spline can move forward and backward. In the past, rotation is restricted.

  Returning to FIG. 3, in the ball screw axial direction, the bolt 100 abuts the front end 96 c of the nut 96 at the retreat limit to abut the flange end 100 c of the bolt 100 to restrict the retreat limit, and the rear end of the spline guide 75. The length of the male spline 113a and the length of the bolt 100 protruding from the rear end of the nut are both set to be equal to or greater than the entire stroke of the rear master piston 62.

  In FIG. 4, the ball screw straightening is performed by the pressure-increasing brake operation control of the electronic control unit 13 based on the operation stroke detection value of the input detector A25 and the operation load detection value of the input detector B26 by the operation of the brake operator 11 of the driver. Power is generated in the motor 110 provided on the outer periphery of the moving mechanism 90.

When the nut 113 that rotates continuously is rotated in the direction in which the bolt 100 moves forward, the rotor 113 of the motor 110 is rotated against the bottom 91a of the housing B91 that is the retreat limit. The bolt 100 pushes the rear master piston 62 by force.

  The input transmission member 35 that connects the brake operator 11 and the rear end strokes while compressing the simulated spring 38 and the simulated traversal 39 constituting the stroke simulator SS, and the acting force is applied to the front end step portion 36 a of the sleeve 36. Although transmitted and applied to the rear end of the thrust bearing 98, the force for pressing the nut 96 by the power of the motor 110 to the backward limit is controlled to be larger.

  In the process of decreasing the input of the brake operator 11, the nut 96 is rotated in the direction in which the bolt 100 moves backward, and the nut 96 is pushed to the backward limit by the high hydraulic reaction force of the master cylinder 60. Until then, the front end of the bolt 100 moves backward from the rear end of the rear master piston 62 without leaving a gap.

  During this pressure-increasing brake control, when the bolt 100 has the advance amount L4, the stroke simulator means SS has a clearance L3 ′ between the rear end 100d of the bolt 100 and the front end 35a of the input transmission member 35. The rigidity of the simulation spring 38 and the simulation rubber 39 which are elastic members is set.

  Therefore, since the input transmission member 35 does not push the bolt 100 that directly contacts the rear master piston 62, the input of the brake operator 11 cannot reinforce the boost of the master cylinder 60, but the brake of the driver The rear master is able to reduce the operation stroke burden of the operator 11 and further reduce the power of the motor 110 by a certain amount so as to obtain a wheel brake braking force obtained by subtracting the electric regenerative braking force from the braking force desired by the driver in the cooperative regenerative braking control. Even if the piston 62 and the bolt 100 are moved backward (maximum retracted amount, L3 ′ in FIG. 4), there is no interference between the rear end 100d of the bolt 100 and the front end 35a of the input transmission member 35. Stroke and vehicle braking force can always be constant.

  In addition, since the input transmission member 35 as an input member strokes independently from the bolt 100 of the output member that is the control target of the electronic control device 13, the electronic control device 13 detects the brake detected by the input detector A25. Since the input / output control using only the stroke detection value of the operating element 11 as a source is established, the input detector B26 constituted by a load sensor for detecting the operating load of the brake operating element 11 can be omitted.

  When the brake operation element 11 and the wheel brakes BFL, BFR, BRL, BRR are separated from each other, a so-called brake-by-wire state is achieved, thereby enabling various controls other than the cooperative regenerative brake control.

  For example, when all of the wheel brakes BFL, BFR, BRL, and BRR are in the ABS operation mode, excessive boosting of the master cylinder 60 should not be necessary, and the electronic control unit 13 that controls the vehicle in an integrated manner Even if one of the wheel brakes BFL, BFR, BRL, and BRR is controlled to reduce the hydraulic pressure of the master cylinder 60 until the ABS operation is finished, there is no interference with the brake operator 11.

Further, even when the brake assist control is performed so as to increase the braking force in an emergency, the brake operator 11 can improve the operation feeling of the driver without following the rapid advance of the rear master piston 62.

  However, in a vehicle that does not require control such as cooperative regenerative braking as described above, the stroke simulator SS is configured so that the rear end 100d of the bolt 100 during pressure-increasing brake operation control can be pushed by the front end 35a of the input transmission member 35. You may set the rigidity of the simulation spring 38 and the simulation rubber | gum 39 which are the elastic members with which it is equipped.

  In such a setting, the thrust of the input transmission member 35 is added to the bolt 100 that is in contact with and pushed against the rear master piston 62, so that the added thrust of the bolt 100 will push out the bolt 100 of the motor 110. Thus, the power assist can be saved and power consumption can be saved, or the generated hydraulic pressure of the master cylinder 60 can be further increased while maintaining the motor power.

  Further, the thrust of the input transmission member 35 that is partially lost to deflect the stroke simulator SS is transmitted to the brake operator 11 together with the reaction force that pushes the bolt 100 as a reaction force, and is a simulation provided for the stroke simulator SS. Appropriate resilience as an elastic member of the spring 38 and the simulation rubber 39 can be imparted.

  In FIG. 4, the pressure increasing brake control corresponding to the input of the brake operator 11 has been described. However, the electronic control unit 13 is based on information from a vehicle sensor (not shown) regardless of whether the brake operator 11 is operated. The master cylinder 60 can be boosted by controlling the motor 110 to perform automatic brake control.

  Regardless of whether or not the brake operator 11 is operated, the brake fluid pressure generating device 10 is boosted to perform automatic braking for keeping a predetermined inter-vehicle distance from the preceding vehicle, and after performing automatic brake control, the ABS 15 is activated to control the outer ring. Alternatively, stability control for applying braking force to the inner wheel, traction control for appropriately applying braking force to the drive wheel, and the like can be performed.

  During such control, even if the brake operator 11 is stepped on, the brake operator 11 is operated without any sense of incongruity due to the rigidity set in advance by the stroke simulator SS. The pressure is also controlled to the fluid pressure desired by the immediate driver.

  FIG. 5 shows the non-intensifying brake operating state of the brake fluid pressure generating device 10, in which the motor 110 does not rotate, and the thrust of the input transmission member 35 is transmitted to the bolt 100 only by the operating force of the brake operator 11 of the driver. Thus, the master cylinder 60 is boosted.

  When the input transmission member 35 strokes a separation distance L3 between the front end 35a of the input transmission member 35 and the rear end 100d of the bolt 100 in FIG. 3, the front end 35a of the input transmission member 35 abuts against the rear end 100d of the bolt 100 and becomes the rear master piston 62. Thrust is transmitted.

  The sleeve 36 presses the front end step portion 36a of the sleeve 36 against the rear end 98a of the thrust bearing 98 while the stroke of the stroke simulator SS is regulated, and this pressing load is applied to the simulation spring 38 and the simulation traverse 39. Although only the deflection load for L3 (FIG. 3) is present, this slight deflection load is transmitted to the bolt 100 collar rear end 100c by the nut 96 front end 96c, and is added to the bolt 100 thrust without waste.

  The thrust of the bolt 100 and the nut 96 is such that the male spline 96b formed on the nut 96 is a female spline 113a formed on the rotor 113, and the male spline 100b formed on the bolt 100 is a female spline formed on the spline guide 75. 75a is slid and transmitted to the rear master piston 62 with high efficiency without rotation of the nut 96 and the rotor 113.

  Even in the process of decreasing the input of the brake operator 11, the front end of the bolt 100 does not leave a gap with the rear end of the rear master piston 62 due to the load of the return springs 73 and 66 of the master cylinder 60 and the generated hydraulic pressure reaction force. The rear end 100c of the bolt 100 collar part moves backward while being in contact with the front end 96c of the nut 96.

  If the nut is restrained from advancing and retracting in the axial direction (Patent Document 1), the rotation of the nut and rotor is indispensable when the bolt is advanced, and the inertial force and motor cogging torque of the rotating body are applied. There will be a significant loss.

  Also, when the motor is locked, if the nut is restrained from advancing and retracting in the axial direction, it is impossible to raise the master cylinder, but in the present invention, it is possible by the aforementioned operation.

  The nut can be moved back and forth in the axial direction, but when the nut is connected to the master piston and the bolt is connected to the brake operator (Patent Document 3), the total length of both connecting points is not changed. It is necessary to use a motor that prevents the nut from rotating and a special ball screw with zero reverse efficiency.

  Further, without the resistance of the powerful diaphragm return spring provided in the conventional negative pressure booster, the embodiment of the present invention only loses the sliding resistance of the two sliding splines as described above when there is no motor power. The master cylinder can be boosted with high efficiency.

  With reference to the stroke simulator characteristics of FIG. 7, when the pressure increasing brake operation control of the brake fluid pressure generator 10 is performed, the stroke simulator SS corresponds to the input of the brake operator 11 in the brake simulator 11. Are operated so that the strokes of C0 to C1 to C2 to C3 are obtained.

  First, when the input of the brake operator 11 is applied, the simulated spring 38 whose spring constant is set lower than the return spring 73 of the master cylinder 60 and the simulation traverser 39 of the stroke simulator SS first begins to bend beyond the set load. The stroke starts at the point of C0.

  When the input of the brake operator 11 is further applied, the simulated traverse 39 stretched in series with the simulated spring 38 also becomes the point of C1, and both the simulated spring 38 and the simulated traversal 39 bend at the same time. Start.

  In the process from the point C0 to the point C1, the input detector A25 detects the operation stroke of the brake operator 11 and the input detector B26 detects the load, and the electronic control unit 13 detects the load based on the detected value. Power is supplied to 110 to increase the contact force of the nut 96 to the retreat limit.

  When the input is further applied and the stroke is increased by the combined spring constant of the simulated spring 38 and the simulated traverse 39, the retainer 37 comes into contact with the forward limit (L1 in FIG. 3 is zero) and becomes the point C2.

  From the point C2 to the point C3 when the input transmission member 35 contacts the forward limit (L1 and L2 in FIG. 3 are zero), the stroke increases with a single spring constant of the simulated traversal 39, and the rubber characteristics of the simulated traversing 39 As a result, a non-linear diagram is obtained.

  As the input of the brake operator 11 decreases, the stroke of the brake operator 11 also decreases so as to fall below the diagram of C3 to C2 to C1 to C0 due to the rubber material hysteresis characteristic of the simulation rubber 39.

  The hysteresis reduces a driver's operation burden, and reduces a feeling of repulsion when a constant pedal force is applied to the brake operator 11.

  With reference to the output hydraulic pressure characteristics shown in FIG. 8, the brake hydraulic pressure generating device is configured so that K0 to K1 to K2 to K3 to K8 indicated by solid lines have the braking force desired by the driver corresponding to the operation amount of the brake operator 11. 10 is a diagram for controlling pressure increasing brake operation 10.

  K0 to K4 to K5 to K6 indicated by broken lines are provided in the vehicle and cooperate with a regenerative braking device (not shown) so that the wheel brake hydraulic pressure is obtained by subtracting the regenerative braking force from the braking force desired by the driver. FIG. 3 is a hydraulic pressure diagram of cooperative regenerative brake operation control for controlling pressure generating brake operation of the generator 10.

  K7 to K8 indicated by two-dot chain lines are hydraulic pressure diagrams of the non-intensifying brake operation in which the motor 110 has no power and only the input of the brake operator 11 is transmitted to the input transmission member 35, the bolt 100 and the rear master piston 62. is there.

  In the pressure-increasing brake operation control for increasing the wheel brake fluid pressure so as to obtain the braking force desired by the driver, first, when the input of the brake operator 11 is applied, the input detector A25 detects the operation stroke of the brake operator 11. The load is detected by the input detector B26, and the electronic control unit 13 becomes the K0 point at which power supply to the motor 110 starts based on the detected value.

  In K0 to K1, so-called hydraulic pressure jumping is performed, and the wheel brake hydraulic pressure is increased to a predetermined pressure all at once in order to cancel the inertial force of the wheels and the drive system.

  In K1 to K2, the output hydraulic pressure is increased approximately in proportion to the brake operation amount, and the K2 point holds the power of the motor 110 and becomes the limit of pressure increase, but the wheel brake is locked (actually) Is set with a sufficient margin for the ABS to operate before the lock.

  When the input of the brake operator 11 is further increased, the thrust that the input transmission member 35 and the sleeve 36 push the nut 96 overcomes the force that the motor 110 presses the nut 96 to the backward limit, and the input transmission member After the nut 96 is reversed until the front end 35a of the 35 abuts against the rear end 100d of the bolt 100, the thrust of the input transmission member 35 is transmitted to the bolt 100 and the rear master piston 62, and the non-intensifying brake operation diagrams K7 to K8 are obtained. Along with this, the K3 point at which the pressure increase is resumed.

  In the cooperative regenerative braking operation control, if the power is supplied to the motor 110 that falls below the line K7 to K8, the nut 96 moves forward and impairs the operation feeling of the brake operator 11, so it is lowered to K0 to K4. After jumping to K4 to K5, the voltage is boosted by being offset substantially parallel to the K7 to K8 line.

  In K5 to K6, the region surrounded by K4 to K5 to K6 to K2 to K1 to K4 is boosted by being offset substantially parallel to the normal pressure increasing brake operation diagram K1 to K2, thereby regenerating the electric regenerative brake. Electric power can be regenerated as power.

  When it is no longer necessary to recover the regenerative power, the wheel brake hydraulic pressure may be increased by moving vertically to the normal pressure increasing brake operation diagram K0 to K1 to K2 to K3.

  FIG. 9 shows a second embodiment of the present invention. The brake fluid pressure generator 2010 is different from the first embodiment in the configuration of the ball screw linear motion mechanism 2090, and includes new or alternative components. The reference numerals are moved up by two digits, and the same reference numerals are given to components having the same operation and substantially the same shape as the first embodiment, and the description thereof is omitted.

  The ball screw linear motion mechanism 2090 includes a driven gear shaft 2113 having a worm wheel gear 2113wh formed on the outer periphery thereof, and a radial bearing that rotatably supports the driven gear shaft 2113 while restricting forward and backward movement in the axial direction. 95, 95 are sandwiched between the housing B2091 and the housing D2092.

  The motor 2110 has a worm gear 2110w formed on a drive gear shaft that is a rotating body of the motor 2110, and a housing that is orthogonal to the axis of the driven gear shaft 2113 so as to mesh with the worm wheel gear 2113wh of the driven gear shaft 2113. B2091 and housing D2092 are connected.

  The nut 96 in which the male spline 96b formed on the outer periphery is inserted into the female spline 2113a formed on the inner periphery of the driven gear shaft 2113 is restricted in relative rotation with the driven gear shaft 2113 (continuous rotation is possible), and The nut 96 constituting the thrust bearing 98 at the rear end, which allows advancement and retraction, is restricted by the housing B2091 so that the retreat limit is freely rotatable.

  On the inner periphery of the nut 96, the bolt 100, whose rotation is restricted, is converted into a linear motion and can be moved forward and backward as in the first embodiment.

  The ball screw linear motion mechanism 2090 configured in this manner moves the bolt 100 forward and backward by the rotation of the nut 96 accompanying the rotation of the worm gear 2120w and the worm wheel gear 2113wh that are engaged with each other so that the axes are orthogonal to each other. The master cylinder 60 can be boosted.

  In the gear pair of the worm gear 2120w and the worm wheel gear 2113wh, the reduction ratio can be set arbitrarily and large in one stage. Therefore, the reduction ratio according to the output characteristics of the motor 2110 is set together with the setting of the ball screw lead. This increases the degree of freedom in motor selection.

  In general, it is known that the reverse efficiency is low in the worm and worm wheel gear pair, and when the rotation of the worm wheel gear is transmitted to the worm gear, a large resistance is involved.

  However, since the low reverse efficiency means that when a high hydraulic pressure is maintained in the master cylinder 60, the high hydraulic pressure reaction force becomes the resistance of the force that reverses the nut 96 and the driven gear shaft 2113. Transmission of reverse force to 2110 is reduced, and power consumption can be greatly saved.

  In the unlikely event that the hydraulic pressure of the master cylinder 60 is increased by the power of the motor 2110, even if the motor 2110 fails and becomes free, the hydraulic pressure and braking force of the existing master cylinder 60 are reduced. Decline can be delayed.

  Further, in the non-intensifying brake operation only by the input of the driver's brake operation element 11, if the nut is constrained in the axial direction as described above, the rotation of the nut is indispensable for the bolt to move forward. Since the worm wheel gear needs to be rotated from the worm wheel gear with the rotation of the nut in an extremely inefficient manner, the present invention enables the axial movement of the nut 96 of the ball screw mechanism. Even if thrust is applied to the bolt 100, the nut 96 does not need to be rotated, and the thrust of the bolt 100 can be transmitted to the master cylinder 60 regardless of the reverse efficiency of the worm and worm wheel gear pair.

  FIG. 10 shows a third embodiment of the present invention. The brake fluid pressure generating device 3010 differs from the second embodiment in the configuration of the ball screw linear motion mechanism 3090, and new or alternative component parts are shown. The reference numerals are incremented by two digits, and the same reference numerals are given to components having the same operation and substantially the same shape as those of the first and second embodiments, and the description thereof is omitted.

  In the ball screw linear motion mechanism 3090, the nut 3096, which forms a spur gear 3096s on the outer periphery, rotates while the thrust bearing 98 abuts against the housing A3031 and the retreat limit is restricted, so that the bolt 100 whose rotation is restricted is obtained. It can be moved forward and backward together with the rear master piston 62.

  Offset from the nut 3096 and the axis of the bolt 100 in parallel, the driven gear shaft 3113 is axially restrained at both ends by bearings 95, 95 and is pivotally supported so as to be sandwiched between the housing A 3031 and the master body 3061. .

  The driven gear shaft 3113 has a worm wheel gear 3113wh formed at the front, a spur gear 3113s extending in the axial direction behind the worm wheel gear 3113wh, and a spur gear 3096s formed on the nut 3096. The nut 3096 is engaged with the driven gear shaft 3113 so that the nut 3096 can rotate and can move forward and backward in the axial direction.

  The motor 2110 is engaged with the housing A 3031 and the master body 3061 so that the worm wheel gear 3113wh formed at the front portion of the driven gear shaft 3113 and 2110w formed on the drive gear shaft which is a rotating member of the motor 2110 are engaged with each other. The shaft 3113 is connected so as to be orthogonal to the axis.

  In the brake hydraulic pressure generator 3010 configured as described above, the spur gear 3113 formed on the driven gear shaft 3113 interlocked with the rotation of the motor 2110 rotates the nut 3096 that forms the meshing spur gear 3096s. Thus, the pressure of the master cylinder 60 is increased.

  When there is no motor power, the tooth surface of the spur gear 3113 s formed on the driven gear shaft 3113 and the tooth surface of the spur gear 3096 s formed on the nut 3096 are arranged in the axial direction as shown by a thin line in FIG. By sliding, the nut 3096 can be moved back and forth, and the master cylinder 60 can be boosted.

  In particular, in the gear pair of the spur gear 3113s and the spur gear 3096s, the tooth shape of the spur gear does not have a torsion angle with respect to the axis of the gear shaft, and the driven gear shaft 3113 is completely rotated as the nut 3096 advances and retreats. The nut 3096 can be smoothly advanced and retracted without being required, and the master cylinder 60 can be boosted with high efficiency.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, in the above embodiment, the motor that rotates the nut of the ball screw linear motion mechanism has been described with a motor using a brush, but a brushless motor, a stepping motor with a high stopping torque, or the like is not limited by the type of motor. You may apply this invention to the used brake device for vehicles.

  Also, in the above embodiment, the thrust ball bearing is used to explain the bearing configuration that allows the nut to rotate to the retreat limit, but other axial loads, thrust roller bearings, tapered roller bearings, etc. were used. The present invention may be applied to a vehicle brake device including a ball screw linear motion mechanism.

  In the above embodiment, the rotating member connected to the motor and the nut have been described as the sliding spline, and the bolt rotation restricting means and the means for enabling the rotation to be connected in a coaxial manner, but the key groove is formed in the shaft and the hole. In addition, the present invention may be applied to a vehicle brake device including a ball screw linear motion mechanism having a key interposed therebetween.

  In the above embodiment, the drive gear is formed on the rotating shaft of the motor, and the driven gear and the nut meshing with the drive gear are described so that they can be continuously rotated and moved back and forth in the axial direction. The present invention may be applied to a vehicle brake device in which an idler gear is interposed between a rotating shaft of a motor and a drive gear.

  Moreover, although the said Example demonstrated as a vehicle brake device provided with a tandem-type master cylinder, you may apply this invention to the brake device for vehicles provided with the single master cylinder with a single master piston.

  In the above-described embodiment, the ball screw shaft, the input transmission member shaft, and the master cylinder shaft are described as a vehicle brake device that is configured coaxially. The present invention may be applied to a vehicle brake device in which each axis is offset or the axis angle is changed.

Brake hydraulic system diagram showing overall configuration of vehicle brake system Cross section of the main part of the left side of the brake fluid pressure generator at the initial non-operation position Cross-sectional enlarged view of the main part of the left side of the brake fluid pressure generator at the initial non-operation position Cross-sectional enlarged view of the main part of the left side of the brake fluid pressure generator at the booster brake operating position Cross-sectional enlarged view of the main part of the left side of the brake fluid pressure generator at the non-intensifying brake operating position 1-1 sectional view and 2-2 sectional view of FIG. Stroke simulator characteristics Output hydraulic pressure characteristics Sectional drawing of the main part of the left side surface at the initial non-operation position of the brake fluid pressure generating device of the second embodiment Cross-sectional view of the main part of the left side surface at the initial non-operation position of the brake fluid pressure generating device of the third embodiment

Explanation of symbols

10, 2010, 3010 Brake fluid pressure generator 11 Brake operator 13 Electronic controller 15 ABS
25 Input detector A
26 Input detector B
27 Output detector 30 Input means 35 Input transmission member 38 Simulated spring as elastic member 39 Simulated traversal as elastic member 60 Master cylinder 62 Rear master piston 68 Front master piston 75 Spline guide 75a, 113a Female spline 90, 2090, 3090 Ball screw linear motion mechanism 96, 3096 Nut 96b, 100b Male spline 98 Thrust bearing 99 Ball 100 Bolt 110, 2110 Motor 113 Rotor 31, 91, 92, 111, 2091, 2092, 3031, 3061 Housing SS Stroke simulator 2110w Drive gear Worm gear 2113, 3113 driven gear shaft 2113wh, 3113wh Worm wheel gear 3113s, 3096s Spur gear F L front fluid pressure chamber RPL rear fluid pressure chamber BFL, BFR, BRL, BRR wheel brake

Claims (9)

  A forward / reverse motor, a ball screw linear motion mechanism that converts the rotation of a nut linked to the motor into a linear motion in the axial direction of a bolt whose rotation is restricted, and the bolt can be pushed. A vehicle brake device comprising: a brake operator linked to a bolt rear end; and a master cylinder linked to the bolt front end at a master piston rear end facing a hydraulic pressure chamber to which a wheel brake is connected; The vehicular brake device, wherein the nut constituting the ball screw linear motion mechanism is capable of moving back and forth in an axial direction, and the rear end of the nut being restricted by a housing.   The nut that constitutes the ball screw linear movement mechanism and the motor are arranged coaxially, and is a rotating member of the motor, which is restrained from advancing and retreating in the axial direction by the housing and is rotatably supported. The vehicular brake device according to claim 1, wherein the nut can be continuously rotated with respect to the rotor and can be moved back and forth in the axial direction.   The nut is connected to the driven gear shaft that is engaged with the rotating drive gear shaft provided in the motor and is restrained from advancing and retreating in the axial direction by the housing and pivotally supported. The vehicular brake device according to claim 1, wherein the vehicular brake device is enabled and can be moved back and forth in the axial direction.   4. The vehicle brake device according to claim 3, wherein the drive gear shaft is a worm gear and the driven gear shaft is a worm wheel gear.   The relative distance between the nut and the input transmission member that allows the bolt to be pushed so that the front end faces the rear end of the bolt and connects the rear end to the brake operator is shortened corresponding to the input of the brake operator. The vehicular brake device according to any one of claims 1 to 4, further comprising a stroke simulator that can be used.   In the stroke simulator, a cylindrical elastic member is provided around the outer periphery of the bolt, and the elastic member is axially compressible between the nut and the input transmission member, and the elastic member and the The vehicle brake device according to claim 5, wherein the input transmission member is configured to be able to advance and retreat in the axial direction continuously with the nut.   The vehicle brake device according to claim 5 or 6, wherein the input transmission member, the bolt, and the master piston are arranged coaxially.   Including an input detector and an electronic control unit, and at least controls the power of the motor so as to prevent the nut from moving forward from the backward limit of the nut due to the forward thrust of the input transmission member transmitted from the brake operator. The rigidity of the stroke simulator is set so that the advance distance of the input transmission member is smaller than the advance distance of the bolt with respect to the nut under control. Vehicle brake system.   Including an input detector and an electronic control unit, and at least controls the power of the motor so as to prevent the nut from moving forward from the backward limit of the nut due to the forward thrust of the input transmission member transmitted from the brake operator. The vehicle brake device according to any one of claims 5 to 7, wherein rigidity of the stroke simulator is set so that the rear end of the bolt being controlled can be pushed by the front end of the input transmission member. .

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