JP4491827B2 - Brake device for vehicle - Google Patents

Description

  The present invention relates to an electrohydraulic vehicle brake device including a brake operator, a motor and a motor direct-acting means, and a master cylinder connected to a wheel brake.

Conventionally, such a brake device for a vehicle is already known from, for example, Patent Document 1 and Patent Document 2.
Japanese Patent No. 3605460 JP 2002-321611 A

  In the above-mentioned Patent Document 1, an assist force is applied to generate a high hydraulic pressure by pushing the master piston from behind by a pushing member connected to a ball screw linear motion mechanism driven by a motor in parallel with the master cylinder axis. Means.

  However, in the assist force applying means configured as described above, automatic brake operation control for generating brake fluid pressure is performed regardless of whether the brake operation member is input, and the brake operation member is operated during the control. In this case, so-called idling of the brake operation member occurs.

  In addition, when control is performed to weaken the assist force in cooperation with the electric regenerative brake, the amount of advance of the master cylinder piston decreases, so the amount of operation of the brake operation member (stroke relative to input) becomes the braking force of the vehicle. It 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.

  Further, in Patent Document 2, the motor power corresponding to the input amount of the brake pedal is added via a rack meshing with the pinion and interlocked with the input amount of the brake pedal to obtain a boost. However, when the master cylinder is operated by the motor alone and the brake is automatically applied, the play increases when the brake pedal is further increased (first embodiment) or the reaction force increases (second and third embodiments). Example).

  In order to operate the input member and the output member with the same stroke even during normal braking operation, the relationship of boost ratio = input member pressure receiving cross-sectional area / output member pressure receiving cross-sectional area is required (second and third). Example) The degree of freedom in design is low, and problems remain in brake operation feeling and function.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an electrohydraulic brake device for a vehicle that is excellent in functionality and feeling while simplifying the structure.

  In order to achieve the above object, a first aspect of the present invention provides a master cylinder connected to a wheel brake, a brake operator, a motor capable of forward and reverse rotation, and a motor that converts rotation of the motor into linear motion. A vehicle brake device comprising: a linear motion means; and an input selection means for selectively transmitting an input from the brake operator and an input from the motor linear motion means to the master cylinder. The selection means is connected to an input transmission member from the brake operator and sets a first predetermined backward limit, and a motor that is connected to the motor linear motion means and sets a second predetermined backward limit The linear movement means input point and the master cylinder output point connected to the master piston pushing member of the master cylinder are any one of the intermediate portion, one end portion, and the other end portion of the floating lever. Individually pivotally connected, and either one of the brake operator input point and the motor linear motion means input point is used as a power point, and the first predetermined retraction limit or the second predetermined retraction limit is determined by inputting the force point. The other is constrained to be a fulcrum, and the input of the power point can be transmitted to the output point of the master cylinder as an action point.

  According to a second aspect of the invention, in addition to the configuration of the first aspect of the invention, the motor linear motion means is constituted by a crank mechanism, and a connecting rod provided in the crank mechanism is pivotally connected to the input selection means. The crank angle of the crank mechanism at the non-operation initial position where both the brake operator input point and the motor linear motion means input point of the input selection means are regulated by the first predetermined backward limit and the second predetermined backward limit. Is set to 90 degrees to 100 degrees before top dead center.

  According to a third aspect of the invention, in addition to the configuration of the first or second aspect of the invention, the motor linear motion means is constituted by a crank mechanism, and a connecting rod provided in the crank mechanism is pivotally connected to the input selection means. Then, the brake operating element input point of the input selection means is constrained to the first predetermined backward limit, and the crank angle of the crank mechanism at the position where the master piston of the master cylinder has a full stroke is determined as the top dead center. It is characterized by being set in the vicinity.

  According to a fourth aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the power transmission means from the motor to the motor linear motion means has a worm provided on the motor side. A gear is used, and the driven gear provided on the motor linear motion means side is constituted by a gear pair having a worm wheel gear.

  According to a fifth aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the input selection means includes a simulator push rod configured as the input transmission member from the brake operator. The relative distance from the reaction force piston that constitutes the first predetermined backward limit of the brake operator input point and that is configured as the input transmission member from the brake operator corresponds to the input of the brake operator. And a stroke simulator for varying the stroke of the brake operator.

  According to a sixth aspect of the invention, in addition to the configuration of the fifth aspect of the invention, the stroke simulator forms a hydraulic chamber, and the reaction force piston is restricted to the first predetermined backward limit. The hydraulic pressure chamber is opened to atmospheric pressure to allow a stroke simulation operation, and when the reaction force piston moves forward by a predetermined amount from the first predetermined backward limit, the hydraulic pressure chamber is made oil tight and the stroke simulation operation is limited. A shut-off valve is provided.

  According to a seventh aspect of the invention, in addition to the configuration of the first aspect of the invention, at least the brake operator input point is advanced from the first predetermined backward limit by an input from the brake operator. Rather than the force to be applied, the force that presses and restrains the brake operating element input point to the first predetermined backward limit is overcome by the input from the motor linear motion means, and the floating lever uses the brake operating element input point as a fulcrum, An electronic control unit is provided for controlling the motor so as to act on the master cylinder output point with the motor linear motion means input point as a power point.

  According to the first aspect of the present invention, the motor linear motion means input point is advanced from the second predetermined backward limit by the force pressing the motor linear motion means input point to the second predetermined backward limit by the input of the brake operator input point. When the force to be applied is greater, the master cylinder can be boosted by turning the floating lever with the brake operator input point as a fulcrum by pressing and restricting the brake operator input point to the first predetermined backward limit.

  Conversely, when the force to advance the brake operator input point from the first predetermined backward limit is greater than the force to press the brake operator input point to the first predetermined backward limit by inputting the motor linear motion means input point, the motor The master cylinder can be boosted by rotating the floating lever with the linear motion means input point pressed and restrained to the second predetermined backward limit and the motor linear motion means input point as a fulcrum.

  A master push rod which is a master piston pushing member that pivotally connects the input of the motor linear motion means input point or the brake operation element input point to the floating lever by the rotation of the floating lever by the so-called high-selling of such input selection means. The output can be transmitted to the master cylinder via

  Here, when the motor power is controlled so that the input of the motor linear motion means input point is output to the master cylinder, the input transmission system of the brake operator temporarily disconnects the mechanical transmission from the master cylinder and the wheel brake. Thus, the brake operation work (input x stroke) of the driver can be reduced.

  And, without reducing the motor power efficiency to about 60-70% like a hydraulic pump used in a conventional hydraulic booster or the like, the motor rotation is converted into a direct motion and the motor power is directly input selection means. And a simple input selection action of the input selection means described above, and thus a lightweight and compact vehicle brake device with excellent mechanical efficiency and reliability can be provided.

  According to a second aspect of the present invention, the motor linear motion means is constituted by a crank mechanism, and the crank angle of the crank mechanism at the initial non-operation position of the input selection means is set to 90 degrees to 100 degrees before top dead center. Therefore, in the vicinity of the initial movement of the motor linear motion means, the connecting rod stroke speed is near the maximum speed (small reduction ratio) with respect to the crank rotation angle, and the motor rotation due to the presence of the electrical time constant and mechanical time constant of the motor 120. Compensating for the rise delay, it is possible to increase the speed (pressure increase speed) of the master piston of the master cylinder in the invalid stroke area of the master cylinder and the idle area where the brake shoe or brake pad is not in contact with the brake drum or the brake rotor.

  On the other hand, the hydraulic reaction force generated in the master cylinder is simultaneously transmitted at high speed from the floating lever to the first predetermined backward limit of the brake operator input point, so that motor power is supplied in conjunction with the sudden operation of the brake operator. Even in this case, the behavior of the brake operator can be stabilized without the brake operator input point once moving forward from the first predetermined backward limit.

  According to a third aspect of the present invention, the motor linear motion means is constituted by a crank mechanism, and the crank angle of the crank mechanism is set near the top dead center during the master piston full stroke of the master cylinder. As the point approaches, the connecting rod stroke speed with respect to the crank rotation angle gradually decreases (large reduction ratio) on the sine curve, and if the master piston is in full stroke where no further stroke is required, crank top dead Since it is in the vicinity of the point, it is possible to set so that almost no moment is generated on the crankshaft and no load is generated on the motor connected to the crankshaft.

  On the other hand, the high hydraulic reaction force generated in the master cylinder is transmitted from the floating lever to the first predetermined backward limit of the brake operator input point in proportion to the hydraulic reaction force. Even when an operating force is applied, the brake operator input point does not advance from the first predetermined backward limit, and the behavior of the brake operator can be stabilized.

  In other words, in the high pressure region near the full stroke of the master piston, the rising hydraulic pressure reaction force is transmitted to the crankshaft (motor) while canceling as the reduction ratio of the crank mechanism increases in a sine curve. The hydraulic reaction force applied to the selection means will rise proportionally.

  If the crank operating angle is set to 90 to 100 degrees before top dead center at the initial non-operating position of the input selection means, and the master piston is set to top dead center during full stroke, Increasing the response of the wheel brake and increasing the pressure, the thrust of the connecting rod can be increased according to the decrease in the required fluid volume of the brake cylinder of the wheel brake, but the thrust can be increased, and the motor can perform the most efficient work. it can.

  According to the invention of claim 4, when the worm gear is driven and the worm wheel gear is driven, power transmission efficiency is good, but conversely, the worm gear is driven and the worm gear is driven. Since the reverse efficiency is extremely low, the load torque transmitted back to the motor is small even when a high load is applied to the motor direct acting means while maintaining the high pressure of the master cylinder, and the motor power consumption can be largely omitted. it can.

  Further, even when the input from the brake operating element exceeds the power of the motor for the input selecting means and the motor direct acting means, the input selecting means inputs the motor direct acting means when switching the brake operator input point to the power point. The operation until the point is retracted to the initial non-operation position and brought into contact with the second predetermined retreat limit can be delayed.

  Therefore, even if the pressure boosting brake is operated by the motor power, even if the motor power suddenly expires, it is possible to delay the decrease in the master cylinder hydraulic pressure that has been increased, and delay the braking force decrease. be able to.

  And, since the brake operator stroke entry due to the reverse of the brake operator input point and the return of the brake operator stroke due to the decrease in the master cylinder hydraulic pressure are slowly canceled out, the behavior change of the brake operator can be made gentle. .

  According to the fifth aspect of the present invention, the input from the motor direct acting means overcomes the input force from the brake operating element applied to the input selecting means, and the reaction force constituting the first predetermined backward limit of the brake operating element input point. The brake operator is provided with a stroke simulator that changes the relative distance between the simulator push rod connected to the brake operator and the reaction force piston in response to the brake operator input when the piston is in the retreat limit. The stroke feeling can be created arbitrarily, the brake operation feeling can be improved, and the operation amount of the brake operator can be referred to as the displacement amount using a potentiometer or stroke sensor. Thus, the brake operation amount of the driver with higher accuracy can be estimated.

  According to the sixth aspect of the present invention, the reaction force that constitutes the first predetermined backward limit of the brake operator input point is obtained by overcoming the power from the motor direct acting means rather than the input from the brake operator acting on the input selecting means. In the state where the piston is in the retreat limit, the simulation operation of the stroke simulator can be allowed and a suitable brake operation feeling can be created, and the power from the motor direct acting means applied to the input selecting means can be applied from the brake operator. When the input is overcome and the reaction force piston that constitutes the first predetermined backward limit of the brake operator input point moves forward by a predetermined amount from the reverse limit, the simulation operation is restricted, so the consumption of the brake operator stroke in the stroke simulator is minimized. This can be spent on pushing the master piston of the master cylinder.

  According to the seventh aspect of the present invention, for example, the reaction force piston is moved to the first predetermined backward limit by only the operation force of the driver or the input from the brake operator using a negative pressure booster (not shown) provided separately. It is possible to move forward from the normal brake operation, and it is also possible to perform the brake operation by motor power in an emergency, etc., but in that case, the master piston of the master cylinder according to the required fluid volume of the wheel brake during normal brake The stroke of the brake operator linked to the stroke is required, and the work of the driver cannot be reduced.

  Therefore, the power of the motor is amplified and controlled so that the electronic controller overcomes at least the brake operator input, the brake operator input point is pressed and restricted to the first predetermined backward limit, and the brake operator input point is used as a fulcrum. By operating the pressure booster (boost) brake of the master cylinder by turning the floating lever, the brake operator input that tries to advance the brake operator input point is defeated by the power of the motor linear motion means. Is not transmitted to the master cylinder.

  Therefore, even when the stroke of the master piston of the master cylinder becomes large due to the required fluid volume required by the wheel brake, the operation stroke of the brake operator can be arbitrarily set by the rigidity of the brake operator or the stroke simulator. Thus, the selection range of the master cylinder diameter can be expanded, the degree of freedom in design can be increased, and for the driver, the amount of braking operation can be reduced while obtaining a sufficient braking force by the motor power.

  Also, when performing automatic brake operation that automatically generates brake fluid pressure regardless of whether or not the brake is operated, the electronic control unit controls the power of the motor linear motion means in response to the vehicle and surrounding conditions, and the reaction force Since the master cylinder is boosted while pushing the piston to the first predetermined backward limit, even when the brake operator is depressed during automatic brake control, the initial position of the brake operator does not change and so-called idling of the brake operator occurs There is nothing to do.

  By the power supply control to the motor of the electronic control device as described above, the input selection means temporarily isolates the mechanical transmission between the brake operator and the wheel brake (master cylinder), but the motor power has some influence. The input selection means mechanically selects the input from the brake operator and transmits it to the master cylinder, so that a highly reliable so-called brake-by-wire can be configured with a simple structure. It becomes possible.

  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.

  FIGS. 1 to 15 show an embodiment of the present invention, FIGS. 1 to 12 show a first embodiment of the present invention, and FIG. 1 is a brake hydraulic pressure system diagram showing an overall configuration of a vehicle brake device. 2 is a cross-sectional view of the main part of the left side of the brake hydraulic pressure generating device at the initial non-operation position, FIG. 3 is a cross-sectional view of the main part of the left side of the brake hydraulic pressure generating device at the boosting brake operating position, and FIG. FIG. 5 is a cross-sectional view of the main part of the left side of the hydraulic pressure generating device at the non-intensifying brake operating position, FIG. 7 is an enlarged sectional view of the main part of the left side surface at the initial non-operation position of the stroke simulator, FIG. 7 is a front sectional view of the main part of the motor linear motion means at the initial non-operation position of the brake fluid pressure generator, and FIG. FIG. 9 is a developed sectional view of the main part of the front of the input selection means, Wheel brake required liquid volume characteristic diagram, Fig. 10 is the connecting rod speed characteristic diagram, 11 is a stroke simulator characteristic diagram, Fig. 12 is a output hydraulic pressure characteristic diagram.

  First, in FIG. 1, a brake fluid pressure generating device 10 attached to a vehicle is connected to a brake operation element 11 that is a brake operation member of a driver, and a master drive unit 90 including a stroke simulator 30 and a motor 120 that can be rotated forward and backward. The tandem master cylinder 60 includes a master reservoir 12 that stores brake fluid.

  The operation amount of the brake operation element 11 is detected by a brake operation amount detection means 25 constituted by an encoder, a potentiometer, etc., and data is transmitted to the electronic control device 13, and the electronic control device 13 has a large rotational force according to the detected value. Is given to the motor 120 that can freely rotate forward and backward, and the electronic control unit 13 refers to the current value of the motor 120 and the value of the output detection means 95 that is provided in the master drive unit 90 and includes an encoder, a potentiometer, and the like. An electric circuit is arranged so that the target generated hydraulic pressure of the cylinder 60 can be feedback-controlled.

  When the input from the brake operator 11 and the input from the motor 120 side are converted as the output to the master cylinder 60, the brake fluid pressure generator 10 selects the larger input to select the master cylinder The master cylinder 60 is provided with a front output port 16F and a rear output port 16R.

  The hydraulic pressures output from the front output port 16F and the rear output port 16R of the master cylinder 60 are guided to the front hydraulic pressure path 17F and the rear hydraulic pressure path 17R, respectively. 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 that is driven by an ABS motor 22 that recirculates brake fluid from the reservoir 21 to the front hydraulic pressure passage 17F side is provided.

  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 that recirculates brake fluid from the decompression reservoir 21 toward the rear hydraulic pressure passage 17R.

  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 according to the situation.

  As described above, the ABS 15 has a function as hydraulic pressure control means that can individually control the wheel brake hydraulic pressure supplied to each wheel brake BFL, BFR, BRL, BRR to an optimum value.

  The electronic control unit 13 integrally controls the motor 120 and the ABS 15 of the brake fluid pressure generation device 10, and the pressure increase brake operation control of the brake fluid pressure generation device 10 according to the operation amount of the brake operator 11. Anti-lock brake control, automatic brake control for automatically generating hydraulic pressure regardless of whether or not the brake operator 11 is operated, and individual wheel brake fluid by controlling the ABS 15 from the automatic brake control. It can perform traction control and vehicle stability control with optimal pressure adjustment.

  Further, the electronic control unit 13 can cope with cooperation with an electric regenerative braking device of a vehicle power source (not shown), and the braking force of the electric regenerative braking device is subtracted from the vehicle braking force desired by the driver. It is also possible to apply cooperative regenerative pressure-increasing brake control to the brake fluid pressure generator 10 so as to obtain wheel brake braking force.

  In FIG. 2, the brake hydraulic pressure generation device 10 that is the initial non-operation position of the first embodiment includes a stroke simulator 30, a master drive unit 90, and a master cylinder 60, and the stroke simulator 30, master drive unit 90, Each of the master cylinders 60 is individually configured as a subassembly, and each is fastened with bolts (not shown) and unitized.

  Although the stroke simulator 30 is sub-assembled individually, functionally, a stroke simulation function that varies the stroke in response to the input of the brake operator 11 and an input selection means 100 that is sub-assembled to the master drive unit 90. The function as the input transmission member 30B from the brake operation element 11 to the rear and the function as the first predetermined backward limit 102K of the input selection means 100 described later are combined.

  The stroke simulator 30 includes a simulator 30A that is built in the simulator body 31 and increases an operation stroke and an operation reaction force according to an increase in the operation amount of the brake operator 11 by an elastic member, and is pivotally supported by the input selection unit 100. A first predetermined retreat limit 102K that supports the reaction force of the reaction force piston 102 to be connected and a shut-off valve SS that appropriately restricts the simulator operation are provided.

  The simulating means 30A includes a hydraulic chamber 37e. The hydraulic chamber 37e is connected to the right casing 92 of the master drive unit 90 via the communication holes 31v and 31h formed in the simulator body 31. It communicates with the master reservoir 12 via the communicating holes 61m drilled in the master body 61 via 92h, 92v, 92m.

  The plurality of communication holes 31v, 31h, 92h, 92v, 92m, and 61m are connected by the plugs 50 and 50 and the seal members 49 and 49 so that there is no leakage of the brake fluid to the outside and the inside of the brake fluid pressure generating device 10. Is done.

  Referring also to FIG. 6, the simulator body 31 has an inner diameter with different diameter steps, and the simulating means 30A assembles the child parts into the inner diameter portion of the sleeve 37 like a cartridge in the inner diameter portion of the small diameter. The outer peripheral corner portion of the rear end of the outer diameter shaft of the sleeve 37 abuts against a locking ring 43 fitted in a groove formed in the circumferential direction of the rear portion of the inner diameter of the simulator body 31 and is internally provided with a limited retreat limit.

  A seal member 38 is attached to the rear portion of the outer diameter shaft of the sleeve 37 and is in sliding contact with the small diameter inner diameter portion of the simulator body 31.

  The inner diameter of the sleeve 37 is formed in a bottomed cylindrical shape with steps with different diameters, and the stroke piston 35 and the piston guide 39 are slidably mounted on the inner diameter portion of the sleeve 37.

  In the stroke piston 35, a simulator push rod 33, which is swingably mounted, is screwed into a yoke 32 and a nut 34, and the yoke 32 is connected to the brake operator 11 (FIG. 1).

  The outer diameter of the stroke piston 35 is formed in a stepped shape with different diameters, and the outer peripheral corner portion of the rear end of the large diameter shaft of the stroke piston 35 is fitted into a groove portion formed in the circumferential direction of the rear portion of the large diameter inner diameter of the sleeve 37. Abutting on the locking ring 42, the backward limit is restricted.

  A seal member 36 is attached to the middle portion of the large-diameter shaft of the stroke piston 35 and is in sliding contact with the large-diameter inner cylindrical portion of the sleeve 37.

  A cylindrical simulation rubber 40 formed of an elastic material such as rubber is inserted into the outer periphery of the small-diameter shaft of the stroke piston 35 with a loose fit.

  The tip of the small-diameter shaft of the stroke piston 35 is configured so that the bottomed cylindrical inner diameter portion of the piston guide 39 is slidable, but has a sufficient clearance so that the inside of the bottomed cylindrical portion is not loosely fitted and sealed. It is done.

  The outer diameter of the piston guide 39 is formed in a stepped shape with different diameters, and the simulated spring 41 is guided to the outer periphery of the small diameter shaft of the piston guide 39 between the bottom portion 37c of the sleeve 37 and the step portion 39c of the piston guide 39. The simulation rubber 40 which is stretched and arranged in series at the step 35a of the stroke piston 35 and the rear end 39a of the piston guide 39 is loosely preloaded.

  The set load of the simulated spring 41 is set to a spring constant that is smaller than the initial load applied to the reaction force piston 102 connected to the input selection means 100 and lower than that of the simulated traversal 40.

  Then, the axial clearance LS1 (FIG. 6) between the step 37c at the front end of the large-diameter inner diameter of the sleeve 37 and the step 39c of the piston guide 39 is set to balance the load on both the simulated spring 41 and the simulated traversal 40. And stretched.

  A plurality of groove-shaped oil passages 39b are formed along the axial direction on the outer periphery of the large diameter shaft of the piston guide 39 to permit the flow of brake fluid in front and rear of the piston guide 39.

  The reaction force piston 102 has a front small-diameter shaft pivotally connected to the floating lever 101 of the input selection means 100, and an outer diameter is formed in a stepped shape with a different diameter at the rear, and a seal member 48 is formed at the middle of the large-diameter shaft. Is attached so that the large-diameter inner diameter portion of the simulator body 31 is slidable, and the small-diameter shaft 102b is slidably inserted into the inner diameter of the stopper piston 44.

  The stopper piston 44 allows the large-diameter inner diameter portion of the simulator body 31 to be slidable with a loose fit of the outer diameter shaft and allows the inner diameter of the stopper piston 44 to have a stepped shape with a different diameter. A small diameter shaft 102b of the reaction force piston 102 is slidable on the small diameter guide portion 44c.

  A plurality of radial slits 44b are formed at the rear end of the stopper piston 44 to secure an oil passage so that the brake fluid can flow between the hydraulic chamber 37e of the simulating means 30A and the master reservoir 12. .

  In the first predetermined backward limit 102K (FIG. 2), the step 102c of the reaction force piston 102 abuts against the front end 44d of the stopper piston 44, and the shaft rear end of the stopper piston 44 abuts against the annular step of the simulator body 31. Thus, the retracting limit of the reaction force piston 102 together with the stopper piston 44 is regulated while the small diameter shaft 102b of the reaction force piston 102 is slidably passed through the stopper piston 44.

  A return spring 45 is stretched between the step portion 102 c of the reaction force piston 102 and the step portion 44 e of the inner diameter of the stopper piston 44. The set load of the return spring 45 is the return springs 66 and 76 of the master cylinder 60. Is smaller than the initial load (reaction force) of the input selecting means 100 to which the reaction force is applied, and the step portion 102c of the reaction force piston 102 and the front end 44d of the stopper piston 44 are in contact with each other in the initial state.

  The return spring 45 functions to close the shut-off valve SS, which will be described later, by separating the reaction force piston 102 and the stopper piston 44 by a predetermined amount SSL when the reaction force piston 102 moves forward.

  The shut-off valve SS shuts off the communication between the hydraulic pressure chamber 37e and the master reservoir 12 when the reaction force piston 102 moves forward by a predetermined amount SSL from the first predetermined backward limit 102K while being separated from the stopper piston 44. is there.

  The shut-off valve means SS includes a plurality of valve holes 37a penetrating the front bottom portion of the sleeve 37 and a donut-shaped valve seat 47 made of a rubber material and baked and bonded to the rear end 44a of the stopper piston 44.

  The rear end 102a of the small-diameter shaft 102b of the reaction force piston 102 inserted into the guide portion 44c of the stopper piston 44 protrudes from the rear end of the valve seat 47 and is in close contact with the front end 37d of the sleeve 37. The valve seat 47 of the stopper piston 44 is set apart with a predetermined amount of SSL clearance, and the hydraulic chamber 37e defined by the simulating means 30A communicates with the master reservoir 12 and fills the brake fluid to atmospheric pressure. It is open.

  Thus, the simulation means 30 </ b> A and the reaction force piston 102 arranged in series serve as the input transmission member 30 </ b> B that transmits the input from the brake operator 11 to the input selection means 100.

  Referring to FIGS. 2 to 5, the master cylinder 60 includes a rear master of the master cylinder 60, which is connected to the master cylinder output point 101 c of the floating lever 101 of the input selection unit 100 so as to freely swing in the vertical direction. The master body 61 is connected to the left casing 91 and the right casing 92 so that the piston 62 can be pushed.

  The master cylinder 60 is of a tandem type, and includes a front master piston 71 that generates fluid pressure at the front output port 16F, a rear master piston 62 that generates fluid pressure at the rear output port 16R, and a rear master piston pusher. And a master push rod 104 which is a moving member.

  In the master body 61, front and rear master pistons 71 and 62 are slidably fitted in a bottomed cylindrical cylinder.

  A master reservoir 12 (see FIG. 1) made of synthetic resin is attached to the upper portion of the master body 61 so that the brake fluid can be supplied to the fluid chambers defined by the front and rear master pistons 71 and 62. Filled with brake fluid.

  In order to replenish brake fluid between the axially intermediate portion of the front master piston 71 and the inner diameter of the master body 61, a replenishment port FSP that opens to the axially intermediate portion of the front master piston 71 is provided in the master body 61 at all times. Is done.

  A cup 72 slidably in contact with the inner surface of the cylinder of the master body 61 is attached to the front portion of the front master piston 71 so as to generate a hydraulic pressure at the front output port 16F. A cup 73 that slides on the inner surface of the cylinder of the master body 61 is mounted on the rear side of the front master piston 71 so as to receive the hydraulic pressure generated at the rear output port 16R.

  The front master piston 71 is provided with a central relief valve 74 that allows the front output port 16F to communicate with the master reservoir 12 when the front master piston 71 returns to the retreat limit position by the biasing force of the return spring 76. . The relief valve 74 is coaxially mounted on the front end of the front master piston 71, and holds the relief valve 74 in the forward position against the spring biasing force of the valve spring 75 when the front master piston 71 is in the retreat limit. Then, when the front master piston 71 moves forward, a valve opening rod 77 whose both ends are fixedly supported by the master body 61 so as to allow the relief valve 74 to be moved backward or closed by the valve spring 75 is allowed. And can be opened and closed.

  Both ends of the valve opening rod 77 are supported by the master body 61 and are inserted into the elongated holes 71a of the front master piston 71 (FIG. 5), and the rear end of the relief valve 74 is in contact with the valve opening rod 77. Is done.

  The relief valve 74 is opened when the front master piston 71 is in the retreat limit by pressing the relief valve 74 with the valve opening rod 77, and the front output port 16F and the master reservoir 12 are communicated with each other. The brake fluid can be supplied to the hydraulic chamber in front of the piston 71. When the front master piston 71 moves forward from the retreat limit, the valve opening rod 77 moves rearward relative to the front master piston 71, so that the relief valve 74 is closed and the pressure applied to the front output port 16F. Can be generated.

  The rear master piston 62 is a stepped shaft having a different diameter, the large diameter shaft is fitted to the cylinder inner diameter of the master body 61, and the small diameter shaft is fitted to the inner end of the guide 67 fitted with a seal member 69 at the rear end of the master body 61. Are respectively slidably fitted.

  An annular stepped portion of the master piston 62 abuts on the front end of the guide 67, and a rear end of the guide 67 abuts on a stopper 70 fitted in a rear end groove portion of the master body 61. There are 62 retreat limits.

  The rear master piston 62 is provided with a cup 63 that slides on the inner diameter of the master body 61 while allowing the brake fluid to flow only from the rear on the front outer periphery, and the rear small-diameter shaft of the rear master piston 62 is mounted on the inner periphery of the guide 67. Touch the cup 68.

  The master body 61 communicates with the master reservoir 12 and the rear output port 16R when the rear master piston 62 is in the retreat limit position. A relief port RP that closes and closes the communication of the output port 16R and a supply port RSP that constantly supplies brake fluid from the master reservoir 12 to the cup 63 and the cup 68 are provided.

  In order to restrict the maximum distance between the front and rear master pistons 71 and 62, the set length of the retainer 65 that contacts the rear end of the front master piston 71 and the return spring 66 that is contracted between the rear master piston 62 is set to the rear master piston. A retainer guide 64 that is 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 76 of the front master piston 71, and the maximum distance between the front and rear master pistons 71 and 62 is set at the rearward limit of the rear master piston 62. The retreat limit of the front master piston 71 is also set at the position where is placed.

  In the master cylinder 60 configured as described above, the rear master piston 62 and the front master piston 71 start to advance simultaneously by the push of the master push rod 104 connected to the master cylinder output point 101c of the floating lever 101. The return spring 76 of the front master piston 71 set to a smaller set load than the return spring 66 of the rear master piston 62 is bent.

  The relief valve 74 is closed at the front master piston 71 and the relief port RP is closed at the rear master piston 62 almost simultaneously.

  After the valve closing operation, the hydraulic pressure corresponding to the forward and backward movement of the rear master piston 62 and the front master piston 71 can be generated at the rear output port 16R and the front output port 16F.

  When the rear master piston 62 and the front master piston 71 return to the retreat limit, the relief valve 74 is opened in the front master piston 71, and the relief port RP is opened in the rear master piston 62, so that the rear output port 16R and the front output port are opened. 16F communicates with the master reservoir 12 to enter an atmospheric pressure release state.

  2 to 4, the master drive unit 90 includes a motor 120, a motor linear motion unit 110 that converts rotation of the motor 120 into a linear motion by a crank mechanism, and an input selection unit 100. .

  The input selection means 100 has a floating lever as a fulcrum with a brake operator input point 101a, which is a connection point between the front part of the reaction force piston 102, which is also the input transmission member 30B from the brake operator 11, and the intermediate part of the floating lever 101. 101 is pivotally connected so as to be swingable in the vertical direction.

  Then, a connecting rod 103 of a crank mechanism configured in the motor linear motion means 110 is pivotally connected to the motor linear motion means input point 101b, which is one end portion of the floating lever 101, so as to freely swing in the vertical direction.

  The connecting rod 103 is connected to the connecting rod large end portion 103a in the vicinity of the outer periphery of the crankshaft 111 and is pivotally connected so as to be swingable in the vertical direction.

  On the other hand, the master cylinder output point 101c, which is the other end of the floating lever 101, pivotally connects the master push rod 104 of the master cylinder 60 so as to freely swing in the vertical direction, and the force generated in the floating lever 101 is generated. 60 to be able to transmit.

  7 and 8 together, in such a master drive unit 90, bearings 96 and 96 support the crankshaft 111 so that the crankshaft 111 can rotate at both ends of the crankshaft 111 of the motor linear motion means 110. 96 and 96 are supported by the left casing 91 and the right casing 92.

  The motor 120 has a main body coupled to the left casing 91 and the right casing 92, and projects a motor shaft 120b into the housing from the front.

  The power transmission means between the motor 120 and the motor linear motion means 110 is constituted by a gear pair in which the motor drive side is a worm gear and the motor driven side is a worm wheel gear.

  A worm wheel gear 111 h is formed on the outer periphery of the crankshaft 111, and the worm wheel gear 111 h is meshed with a worm gear 120 w formed on the motor shaft 120 b of the motor 120.

  The rotation direction of the motor 120 is controlled by the electronic control unit 13 so as to freely rotate forward and backward. The power of the crankshaft 111 is transmitted from the worm gear 120w to the worm wheel gear 111h according to the rotation direction of the motor 120. The direction of rotation is also controlled so as to be freely reversible.

  Incidentally, although it is generally known that the power transmission efficiency from the worm gear to the worm wheel gear is high, conversely, the power transmission efficiency from the worm wheel gear to the worm gear is known to be low. The reverse efficiency of power transmission from the worm wheel gear 111h to the worm gear 120w of the motor 120 is set to be extremely small.

  Due to the effect of this low reverse efficiency, even when it is intended to maintain the rotational position of the crankshaft 111 in a state where a large amount of power is applied to the motor 120 and a large rotational force is transmitted to the crankshaft 111, the motor 120 Only a small rotational force needs to be applied, and the power consumption applied to the motor 120 can be kept extremely small.

  In order to detect the rotation angle of the crankshaft 111, a detection shaft 95d of the output detection means 95 whose body is fixed to the right casing 92 is inserted in the axial direction from the right end of the crankshaft 111.

  The rotation angle value detected by the output detecting means 95 is sent to the electronic control unit 13 and is relative to the target rotation amount of the motor 120 (target generated hydraulic pressure of the master cylinder 60) controlled by the electronic control unit 13. Thus, feedback is performed so that correction control can be performed together with a separately sampled motor current value and the like.

  FIG. 8 is a developed front sectional view of the motor direct acting means 110 and the input selecting means 100. A sliding portion formed on the connecting rod 103 near the outer periphery of the crankshaft 111 is pivoted by a pin 111P. The connecting rod is connected to form the connecting rod large end portion 103a.

  The floating lever 101 pivotally connects a reaction force piston 102 to a central sliding portion with a pin 101aP to constitute a brake operator input point 101a.

  The sliding portion on one end side of the floating lever 101 is pivotally connected to the connecting rod small end portion of the connecting rod 103 by a pin 101bP to constitute the motor linear motion means input point 101b.

  Further, at the other end of the floating lever 101, a pin 101cP pivotally connects a sliding portion formed at the rear end of the master push rod 104 to constitute a master cylinder output point 101c.

  With reference to the initial non-operation position of FIG. 2, in the motor direct-acting means 110 and the input selecting means 100, a stopper piece 111 </ b> K provided on the left side of the crankshaft 111 and a stopper receiving portion 91 </ b> K protruding from the left casing 92 are provided. The reverse rotation of the crankshaft 111 is restricted by contact, and the backward movement of the motor linear motion means input point 101b, which is the connection point between the connecting rod 103 connected to the crankshaft 111 and the floating lever 101, from the inoperative initial position is restricted. A second predetermined backward limit 103K is configured.

  Then, when the biasing force of the return springs 76, 66 of the master cylinder 60 is applied to the master cylinder output point, the floating lever 101 in the clockwise direction in FIG. The reaction force piston 102 constituting the input transmission member 30 </ b> B from the brake operator 11 is brought into contact with the first predetermined backward limit 102 </ b> K together with the stopper piston 44 by the power, and is a connection point between the reaction force piston 102 and the floating lever 101. The backward movement of the brake operator input point 101a from the non-operation initial position is restricted.

  Further, the rear end of the master push rod 104 that urges the reaction force piston 102 to the first predetermined retreat limit 102K via the floating lever 101 by the urging force of the return springs 76 and 66 of the master cylinder 60 is a convex portion 104K. It is located with a slight gap.

  In such an input selection means 100, the motor linear motion means input point 101b is moved to the second predetermined backward movement by the force pressing the motor linear motion means input point 101b to the second predetermined backward movement limit 103K by the input of the brake operator input point 101a. When the force for moving forward from the limit 103K is larger, the brake cylinder input point 101a is pressed and constrained to the first predetermined backward limit 102K, and the floating cylinder 101 is turned with the brake operator input point 101a as a fulcrum. 60 boosts are possible.

  On the contrary, the force that advances the brake operator input point 101a from the first predetermined backward limit 102K by the force that presses the brake operator input point 101a to the first predetermined backward limit 102K by the input of the motor linear motion means input point 101b. When this is larger, the master cylinder 60 can be boosted by rotating the floating lever 101 with the motor linear motion means input point 101b as a fulcrum by pressing and restricting the motor linear motion means input point 101b to the second predetermined backward limit 103K. become.

  In other words, the input selection means 100 has a three-point equalizer structure, and in order to constrain one point, the floating lever 101 floats while swinging or swinging in order to equalize the moment applied to both ends.

  The master piston pushing member that pivotally connects the input of the motor direct acting means input point 101b or the brake operating element input point 101a to the floating lever 101 by the rotation of the floating lever 101 by the so-called Hisele of the input selecting means 100. The output can be transmitted to the master cylinder 60 through the master push rod 104.

  With reference to FIGS. 2 to 3, the total operating angle setting of the crankshaft 111 is from the initial position until the connecting rod 103 transitions from the initial position to the top dead center 111 TDC of the connecting rod 103 indicated by a two-dot chain line in FIG. At the dead center 111TDC, as shown in FIG. 3, the front part of the master cylinder 60 and the rear master pistons 71 and 62 are set in the vicinity of the full stroke so as to have a full operating angle θC.

  The non-operation initial position of the connecting rod large end portion 103a of the crankshaft 111 is set to a position reversed by 90 to 100 degrees with respect to the position of the connecting rod large end portion 103a at the top dead center 111TDC.

  Therefore, the total operating angle θC of the connecting rod large end portion 103a of the crank mechanism constituting the motor linear motion means 110 is set to 90 to 100 degrees.

  Referring to the wheel brake required fluid quantity characteristic diagram of FIG. 9, the required fluid quantity characteristics of the wheel brakes (BFL, BFR, BRL, BRR) connected to the master cylinder 60 are the wheel brakes (BFL, BFR, BRL, BRR). ), The low pressure region where there is a gap (play) between the brake shoe or brake pad and the brake drum or brake rotor requires the most amount of fluid, and as the hydraulic pressure increases, the compression strain of the brake shoe or brake pad saturates. It is known that the liquid volume also decreases.

  Therefore, in the low pressure region where the hydraulic pressure (reaction force) is small and play is large, the required torque of the crankshaft 111 may be small, but the connecting rod 103 is required to generate a high stroke speed.

  Further, the master cylinder 60 also has an invalid stroke which is a distance until the cup 63 of the rear master piston 62 passes through the relief port RP and a distance until the relief valve 74 is seated on the front master piston 71. Although the required torque of the crankshaft 111 may be small at the position, the connecting rod 103 is required to generate a large stroke speed.

  Conversely, in the high pressure region of the wheel brake (BFL, BFR, BRL, BRR), the stroke speed of the connecting rod 103 with respect to the rotation angle of the crankshaft 111 may be relatively low, but the crankshaft 111 is required to have a large torque. The

  Referring to the connecting rod speed characteristic diagram of FIG. 10, in the motor linear motion means 110 in which the region surrounded by the broken line is set as the crank total operating angle θC, the stroke speed of the connecting rod 103 with respect to the rotation angle of the crankshaft 111 in the initial movement from the initial position. The stroke speed of the connecting rod 103 with respect to the rotation angle of the crankshaft 111 gradually changes with a sine curve and decreases with the transition to the top dead center 111TDC.

  In the initial movement of the motor direct-acting means 110 whose initial position is set to 90 to 100 degrees before the top dead center, the connecting rod 103 operates from the vicinity of the highest speed, and the electric time constant and mechanical properties of the motor 120 are Compensating for the delay in the rise of the motor rotation due to the presence of the time constant, it is possible to quickly pass the invalid stroke distance of the master cylinder 60 and increase the brake fluid filling speed in the wheel brake (BFL, BFR, BRL, BRR) play area.

  Further, as the required fluid amount of the wheel brakes (BFL, BFR, BRL, BRR) is small, the speed of the connecting rod 103 gradually decreases as the fluid pressure load increases and the rear portion of the master cylinder 60 and Near the full stroke of the front master pistons 62 and 71, the crank angle of the motor linear motion means 110 is also near the top dead center, the moment of the crankshaft 111 is reduced, and the crankshaft 111 and the motor 120 are hardly loaded. It will be.

  3, the power of the motor 120 is controlled so that the input selection means 100 selects the input of the motor linear motion means input point 101b and outputs it to the master cylinder 60. To do.

  The force for moving the motor linear motion means input point 101b forward from the second predetermined backward limit 103K is larger than the force for pressing the motor linear motion means input point 101b to the second predetermined backward limit 103K by the input of the brake operator input point 101a. The motor 120 is controlled so that the brake cylinder input point 101a is pressed and constrained to the first predetermined backward limit 102K, and the floating cylinder 101 is turned around the brake operator input point 101a as a master cylinder. 60 boosts are performed.

  In FIG. 3, the rear master piston 62 and the front master piston 71 of the master cylinder 60 are in a full stroke state, and the hydraulic reaction force of the master cylinder 60 that has become high pressure is connected to the connecting rod via the master push rod 104 and the floating lever 101. 103.

  At this time, as described above, the connecting rod 103 is located at the top dead center 111 TDC in FIG. 2, so the high hydraulic reaction force of the master cylinder 60 does not act as a moment on the crankshaft 111, but the brake operator input Since the force that presses and restrains the point 101a to the first predetermined backward limit 102K is increased in proportion to the hydraulic reaction force, even when a strong operating force is applied to the brake operator 11, the brake operator input point 101a does not advance from the first predetermined backward limit 102K.

Here, when the pushing force of the connecting rod 103 is Fp, the distance from the brake operator input point 101a to the motor linear motion means input point 101b is L1, and the distance from the brake operator input point 101a to the master cylinder output point 101c is L2. The piston pushing force Fc of the master cylinder 60 is
Fc = Fp × L1 / L2
It becomes.

  The action reaction force applied by the reaction force piston 102 to the first predetermined backward limit 102K is approximately Fp + Fc.

  Here, the operation of the stroke simulator 30 when the driver operates the brake operator 11 and the brake fluid pressure generating device 10 operates the pressure increasing brake by the electronic control device 13 will be described.

  Referring also to FIG. 6, in a state where the reaction force piston 102 is pressed together with the stopper piston 44 against the first predetermined backward limit 102K, the rear end 102a of the reaction force piston 102 abuts against the front end 37d of the sleeve 37, Since the sleeve 37 is held at the initial position, the valve seat 47 of the stopper piston 44 and the valve hole 37a of the sleeve 37 are separated by a predetermined amount SSL, the shut-off valve SS is opened, and the master reservoir 12 ( The distribution of brake fluid with Fig. 1) is allowed.

  Thus, the sliding of the stroke piston 35 and the piston guide 39 of the simulating means 30A is allowed in the hydraulic pressure chamber 37e in the atmospheric pressure open state.

  First, since the set load of the simulation spring 41 of the stroke simulator 30 is set to be smaller than the initial load of the input selection means 100 to which the reaction force of the master cylinder 60 is applied in the initial operation of the brake operator 11, the reaction force The piston guide 39 starts a stroke before the piston 102 starts to advance.

  Then, the brake operation amount detection means 25 quickly detects the operation amount of the brake operator 11 and sends the detected value to the electronic control unit 13.

  Subsequently, the electronic control unit 13 responds to the detection value of the brake operation amount detection means 25, supplies a large amount of power to the motor 120 to generate a high hydraulic pressure in the master cylinder 60, and generates the reaction force at the first predetermined backward limit 102K. Is added to the reaction force piston 102 that is pressed and restrained by the pressure.

  At the inner diameter of the sleeve 37, the stroke of which is regulated by the reaction force piston 102 supported by the first predetermined backward limit 102K and pressed to the reverse limit, the stroke piston 35 is associated with the deflection of the simulated spring 41 and the simulated rubber 40. Thus, the stroke simulating operation of the brake operator 11 is performed.

  Referring to the stroke simulator characteristics of FIG. 11, when the shut-off valve means SS of the stroke simulator 30 is open, the stroke of the brake operator 11 increases as the input of the brake operator 11 increases. -Changes to the diagram of C3.

  First, when an input from the brake operator 11 is applied, the stroke rises at a point C0 exceeding the set load of the simulated spring 41 stretched in the sleeve 37 of the stroke simulator 30.

  In the vicinity of the point C0, the pressure increase hydraulic reaction force is already supported by the first predetermined backward limit 102K by the rotation of the motor 120 corresponding to the detection value of the brake operation amount detection means 25.

  When the input of the brake operator 11 is further applied, the set load of the simulation traversal 40 stretched in series with the simulation spring 41 and applied with the preload is exceeded, and the simulation spring 41 and the simulation traversal 40 are connected. It becomes the point of C1 where both begin to bend at the same time.

  When the input is further applied and the stroke increases with the combined spring constant of the simulated spring 41 and the simulated traversal 40, the step portion 39c of the piston guide 39 comes into contact with the step portion 37b of the sleeve 37 (in FIG. 6). LS1 is zero), and the stroke of the piston guide 39 is restricted to the C2 point.

  From the C2 point to the full stroke C3 point, the stroke increases with a single spring constant of the simulated traversal 40, and becomes a non-linear diagram due to the rubber characteristics of the simulated traversal 40.

  As the input of the brake operator 11 decreases, the stroke of the brake operator 11 also decreases nonlinearly as in C3-C0 with hysteresis below the C3-C2-C1-C0 diagram.

  In FIG. 3, the pressure increasing brake operation of the master cylinder 60 accompanying the operation of the brake operation element 11 is illustrated and described. However, in the automatic brake operation, an appropriate hydraulic pressure is applied to the master cylinder 60 regardless of the operation of the brake operation element 11. The transmission of the acting force from the motor 120 to the master cylinder 60 via the motor direct acting means 110 and the input selecting means 100 is the same in both the pressure increasing brake operation and the automatic brake operation. .

  In the non-intensifying brake operation of the brake fluid pressure generating device 10 when the vehicle power source of FIG. 4 is not started up, the motor 120 and the motor direct acting means 110 are not subjected to pressure increasing control in the initial position state. In addition, the initial reaction reaction force of the master cylinder 60 is applied to the first predetermined backward limit 102K via the input selection means 100.

  In the stroke simulator 30, when the brake operator 11 is input, the stroke piston 35 moves along with the simulation rubber 40 and the piston guide 39, only the simulation spring 41 having a low set load, and strokes. The step portion 39c of the piston guide 39 abuts on the step portion 37b.

  In the process in which the stepped portions 37b and 39c abut, the input load applied to the reaction force piston 102 from the brake operator 11 is applied to the reaction force piston via the input selection means 100 by the initial reaction force of the master cylinder 60. The reaction force is exceeded.

  When rotation of the floating lever 101 (counterclockwise in FIG. 4) is started with the motor linear motion means input point 101b as a fulcrum, the stopper piston 44 is left behind and the reaction force piston 102 and the sleeve 37 are set to a predetermined amount. When the SSL advances, the valve seat 47 provided in the stopper piston 44 and the valve hole 37a of the sleeve 37 are in close contact with each other and the shut-off valve SS is closed by the biasing force of the return spring 45 stretched between the reaction force piston 102 and the stopper piston 44. Thus, the communication between the hydraulic chamber 37e and the master reservoir 12 is blocked.

  In the hydraulic chamber 37e in which the shut-off valve SS is closed, the brake fluid, which is an incompressible fluid, becomes oil-tight (oil lock), so that the stroke of the stroke piston 35 at the inner diameter of the sleeve 37 can be limited. .

  At this time, the pressure in the hydraulic pressure chamber 37e is increased, but since the valve hole 37a of the shut-off valve means SS has a small diameter, the biasing force of the return spring 45 is greater than the force for separating the valve hole 37a from the valve seat 47. The shut-off valve means SS is set not to open.

  Then, the front end 37d of the sleeve 37 pushes the stopper piston 44 and the reaction force piston 102 to transmit the input of the brake operator 11 to the input selection means 100. The input selection means 100 uses the motor linear motion means input point 101b as a fulcrum. The master cylinder 60 is boosted by rotating the floating lever 101.

  Therefore, the stroke of the brake operator 11 after the shut-off valve SS is closed provided in the stroke simulator 30 is consumed only for the boost operation of the master cylinder 60 due to the limitation of the simulation operation.

  Note that the full stroke amount of the stroke piston 35 in the sleeve 37 is set so that the master cylinder 60 can be sufficiently boosted even if the shutoff valve SS has a problem such as a leak. .

  In the input selection means 100, there is no force to press the brake operator input point 101a against the first predetermined backward limit 102K by the input of the motor linear motion means input point 101b, and the brake operator input point 101a is moved from the first predetermined backward limit 102K. Since the forward force is naturally greater, the master cylinder is controlled by rotating the floating lever 101 with the motor linear motion means input point 101b as a fulcrum by pressing and restraining the motor linear motion means input point 101b to the second predetermined backward limit 103K. 60 boosts are performed.

In this non-intensifying brake operation, the pushing force of the reaction force piston 102 by the input of the brake operator 11 is Fm, the distance from the brake operator input point 101a to the motor linear motion means input point 101b is L1, and the motor linear motion means input point When the distance from 101b to the master cylinder output point 101c is L3, the piston pushing force Fc of the master cylinder 60 is
Fc = Fm × L1 / L3
It becomes.

  FIG. 12 shows output hydraulic pressure characteristics, and K0 to K1 to K2 to K3 to K8 indicated by solid lines correspond to the operation amount (input) of the brake operator 11 so that the braking fluid desired by the driver is obtained. FIG. 3 is a hydraulic pressure diagram of wheel brake hydraulic pressure generated by the pressure generator 10 for pressure-increasing brake operation control.

  K0 to K4 to K5 to K6 indicated by broken lines are provided in the vehicle in cooperation with an electric regenerative braking device (not shown) so that the brake fluid is adjusted to a wheel brake fluid pressure 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 braking operation control in which the pressure generator 10 is subjected to pressure increase control.

  K7 to K8 indicated by alternate long and short dash lines do not have the pressure-increasing brake action of the motor 120 and the motor direct-acting means 110, and only the input of the brake operating element 11 is passed through the reaction force piston 102 and the input selecting means 100 to FIG. 6 is a hydraulic pressure diagram of non-intensifying brake operation in which a piston 62 and a front master piston 71 are pushed forward.

  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, when the brake operator 11 is operated, the brake operation amount detecting means 25 detects the operation amount, and the electronic control unit 13 is the motor. It becomes the K0 point at which the pressure increase of the master cylinder 60 is started by controlling the rotation of the 120 and the motor linear motion means 110 to the forward rotation side.

  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.

  At K1 to K2, the output hydraulic pressure is increased in proportion to the operation amount of the brake operator 11, and at the K2 point, the forward rotation of the motor 120 is temporarily stopped and the pressure increase control is stopped. It is set with a sufficient margin for locking (actually ABS operates before locking).

  When the input of the brake operation element 11 is further increased, the thrust of the reaction force piston 102 by the brake operation element 11 becomes stronger than the thrust of the reaction force piston 102 applied by the motor 120 and the motor linear motion means 110. With the forward movement of the force piston 102 away from the first predetermined backward limit 102K, the master cylinder 60 is actuated by the non-intensifying brake by the rotation of the floating lever 101 about the motor direct acting means input point 101b of the input selecting means 100. The K3 point at which pressure increase is resumed along the hydraulic pressure diagrams K7 to K8.

  At this time, due to the effect of the low reverse efficiency of the worm gear and the worm wheel gear described above, the motor linear motion means input point 101b is retracted while delaying the time to the second predetermined backward limit, and then the motor linear motion means input point. 101b serves as a fulcrum, and the master cylinder is boosted again using the brake operator input point 101a as a power point and the master cylinder output point 101c as an action point.

  In the cooperative regenerative braking operation control, if the pressure increase control is performed on the motor 120 and the motor linear motion means 110 so as to fall below the line K7 to K8, the reaction force piston 102 may move forward, and the operation feeling of the brake operator 11 is reduced. Therefore, after jumping from K0 to K4 lower than the normal pressure increase control, the voltage is boosted by offset substantially parallel to the K7 to K8 line, and the K4 to K5 diagram is obtained.

  In K5 to K6, the electric power is generated by using the region surrounded by K4 to K5 to K6 to K2 to K1 to K4 as the regenerative braking force of the regenerative brake by increasing the pressure by offsetting substantially parallel to the normal pressure increase diagram K1 to K2. Can be regenerated.

  When supply of regenerative power is no longer necessary, 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.

  Further, since the shut-off valve SS of the stroke simulator 30 is opened even during the cooperative regenerative braking operation, the stroke of the brake operator 11 with respect to the input of the brake operator 11 has characteristics as shown in FIG. Although the wheel brake hydraulic pressure is reduced by the coordinated regenerative control, an electric regenerative braking force is generated equal to the reduced amount. Therefore, the total braking force of the vehicle is equivalent to the normal pressure increasing brake operation. There is no sense of incongruity between the stroke amount and the generated braking force.

  FIG. 13 shows a second embodiment of the present invention. The brake fluid pressure generator 210 differs from the first embodiment in the configuration of the master drive unit 290, and has the same function and shape as the first embodiment. Also, parts that are substantially the same are denoted by the same reference numerals and description thereof is omitted.

  In the master drive unit 290 of the second embodiment, the input / output point of the input selection means 100 is different from that of the first embodiment, and the connecting rod 103 is provided at the motor linear motion means input point 101b at one end of the floating lever 101 in the first embodiment. The reaction force piston 102 to which the input from the brake operator 11 is transmitted is connected to the brake operator input point 101 a that is connected in the opposite direction to the other end and moved to the other end of the floating lever 101. A master push rod 104 that pushes the master cylinder 60 is connected to the master cylinder output point 101c that has moved to the intermediate portion.

  The operation of the pressure-increasing brake of the second embodiment is basically the same as that of the first embodiment, and the crankshaft 111 is counterclockwise in FIG. The floating lever 101 rotates clockwise with the brake operator input point 101a as a fulcrum, and the master push rod 104 connected to the master cylinder output point 101c is pushed to increase the pressure of the master cylinder 60. To get.

  The non-intensifying brake operation is basically the same as that of the first embodiment, the crankshaft 111 having no driving force of the motor 120 is limited in reverse rotation and the backward movement of the connecting rod 103 is limited, and the floating lever 101 is linearly operated by the motor. With the means input point 101b as a fulcrum, the master push rod 104 connected to the master cylinder output point 101c is pushed by the counterclockwise rotation by the advance of the reaction force piston 102 to boost the master cylinder 60. .

  FIG. 14 shows a third embodiment of the present invention. The brake hydraulic pressure generator 310 differs from the first embodiment in the configuration of the master drive unit 390, and has the same function and shape as the first embodiment. Also, parts that are substantially the same are denoted by the same reference numerals and description thereof is omitted.

  In the master drive unit 390 of the third embodiment, the input / output points of the input selection means 100 are different from those of the first embodiment, and the brake operator input point 101a moved to one end of the floating lever 101 is connected to the brake operator 11 from the brake operator 11. The connecting rod 103 is connected to the motor linear motion means input point 101b which has moved to the intermediate portion of the floating lever 101, and the master cylinder output point 101c at the other end of the floating lever 101 is transmitted. The master push rod 104 that pushes the master cylinder 60 is connected in the opposite direction to that of the first embodiment.

  The pressure-increasing brake operation of the third embodiment is basically the same as that of the first embodiment, and the crankshaft 111 is counterclockwise in FIG. The floating lever 101 rotates clockwise with the brake operator input point 101a as a fulcrum, and the master push rod 104 connected to the master cylinder output point 101c is pushed to increase the pressure of the master cylinder 60. To get.

  The non-intensifying brake operation is basically the same as that of the first embodiment, the crankshaft 111 having no driving force of the motor 120 is limited in reverse rotation and the backward movement of the connecting rod 103 is limited, and the floating lever 101 is linearly operated by the motor. With the means input point 101b as a fulcrum, the master push rod 104 connected to the master cylinder output point 101c is pushed by the clockwise rotation of the reaction force piston 102, and the master cylinder 60 is boosted.

  FIG. 15 shows a fourth embodiment of the present invention. The brake hydraulic pressure generator 410 differs from the first embodiment in the configuration of the master drive unit 490, and has the same function and shape as the first embodiment. Also, parts that are substantially the same are denoted by the same reference numerals and description thereof is omitted.

  In the master drive unit 490 of the fourth embodiment, a booster lever 406 that is pivotally connected to the input selecting means 100 is added to the first embodiment, and the booster lever 406 is provided on a boss portion that protrudes from the right casing 92. The booster lever 406 a is pivotally movable in the vertical direction, and the booster lever operating point 406 c in the middle of the booster lever 406 is connected to the brake operator input point 101 a of the floating lever 101.

  The booster lever 406 is connected to the reaction force piston 102 below the booster lever 406, and the booster lever force point 406 b is configured so that the elongated hole 406 d of the booster lever 406 can convert the direct movement of the reaction force piston 102 into the rotation of the booster lever 406. ing.

  The pressure-increasing brake operation of the fourth embodiment is basically the same as that of the first embodiment, and the motor 120 is controlled in conjunction with the operation amount of the brake operator 11 to rotate the crankshaft 111 clockwise in FIG. The floating lever 101 rotates counterclockwise around the brake operator input point 101a as a fulcrum, and the master push rod 104 connected to the master cylinder output point 101c is pushed to increase the pressure of the master cylinder 60. To get.

  At this time, in the fourth embodiment, the hydraulic reaction force generated by the master cylinder 60 generated at the brake operator input point 101 a of the floating lever 101 is transmitted to the reaction force piston 102 via the booster lever 406.

  The non-intensifying brake operation is basically the same as that of the first embodiment, and the crankshaft 111 without the driving force of the motor 120 is limited in reverse rotation to limit the backward movement of the connecting rod 103, and the reaction force piston 102 moves forward. When the booster lever 406 is rotated clockwise, it is transmitted to the brake operator input point 101a, and the floating lever 101 is rotated counterclockwise with the motor linear motion means input point 101b as a fulcrum, thereby providing a master cylinder output point. The master push rod 104 connected to 101c is pushed to raise the pressure of the master cylinder 60.

Here, the pushing force of the reaction force piston 102 is Fm, the distance from the brake operator input point 101a to the motor linear motion means input point 101b is L1, the distance from the motor linear motion means input point 101b to the master cylinder output point 101c is L3, When the distance from the booster lever fulcrum 406a to the booster lever force point 406b is L4 and the distance from the booster lever fulcrum 406a to the booster lever operating point 406c is L5, the piston pushing force Fc of the master cylinder 60 is
Fc = Fm × L4 / L5 × L1 / L3
It becomes.

  In the fourth embodiment, since L4 / L5 × L1 / L3≈1 is set, Fc≈Fm, and the pushing force of the reaction force piston 102 and the pushing force of the master push rod 104 are substantially the same. For example, the pressure increase of the master cylinder 60 during the non-pressure increasing operation can be increased without changing the inner diameter of the master cylinder 60 or the lever ratio of the brake operator 11.

  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 direct-acting means of the master drive unit is a crank mechanism as described in claim 1, but the motor and the input selecting means are used using direct-acting mechanisms such as an eccentric cam, a ball screw, and a rack and pinion. Can also be linked.

  In the above embodiment, the distance between the intermediate portion and one end portion of the floating lever and the distance from the intermediate portion to the other end portion are shown to be approximately equal, but this lever ratio is the same as that of the motor, the motor linear motion means, and the brake operator. It is of course possible to change the distance between the intermediate portion and one end of the floating lever and the distance from the intermediate portion to the other end in an unequal length in accordance with specifications such as the lever ratio.

  Although the above embodiment has been described in the form of a brake operator (pedal) that is operated by foot movement, it can also be applied to a manual brake lever brake system of a bar handle vehicle such as a motorcycle or a four-wheel buggy.

  In the above embodiment, a vehicle brake device including a tandem master cylinder has been described. However, the present invention is applied to a vehicle brake device including a single master cylinder in which a single master piston is slidably accommodated in a master body. It is also possible to do.

  In the above embodiment, the operation has been described using terms such as forward, reverse, forward rotation, reverse rotation, etc., but this is not a direction corresponding to the traveling direction of the vehicle, but the forward or This is expressed using reverse rotation or reverse rotation when the master cylinder performs a step-down action using forward rotation or the like.

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 section of the main part on the left side of the brake fluid pressure generator at the booster brake operating position Cross section of the main part on the left side of the brake fluid pressure generator at the non-intensifying brake operating position Cross-sectional view of the main part of the master cylinder and stroke simulator at the initial non-operation position of the brake fluid pressure generator Cross-sectional enlarged view of the main part of the left side of the stroke simulator at the initial non-operation position Cross-sectional view of the main part of the motor linear motion means at the initial non-operation position of the brake fluid pressure generator Front main part expanded sectional view of motor direct acting means and input selecting means Wheel brake required fluid characteristics Connecting rod speed characteristics Stroke simulator characteristics Output hydraulic pressure characteristics Main part block diagram of brake hydraulic pressure generator of second embodiment Main part block diagram of brake hydraulic pressure generator of third embodiment Main part block diagram of brake hydraulic pressure generator of 4th Example

Explanation of symbols

10 Brake fluid pressure generator 11 Brake operator 13 Electronic controller 15 ABS
25 Brake operation amount detection means 30 Stroke simulator 30B Input transmission member 33 Simulator push rod 60 Master cylinder 90 Master drive unit 100 Input selection means 101 Floating lever 101a Brake operation element input point 101b Motor linear motion means input point 101c Master cylinder output point 102 Reaction force piston 102K First predetermined backward limit 103 Connecting rod 103K Second predetermined backward limit 104 Master push rod 110 Motor direct acting means 111 Crankshaft 111h Worm wheel gear 120 Motor 120w Worm gear BFL, BFR, BRL, BRR Wheel brake SS Shut-off valve

Claims (7)

  A master cylinder connected to the wheel brake, a brake operation element, a motor that can be rotated in forward and reverse directions, a motor linear motion means that converts the rotation of the motor into a direct motion, an input from the brake operation element, and a motor direct motion And an input selection means for selectively transmitting the input from the movement means to the master cylinder, wherein the input selection means is connected to an input transmission member from the brake operator. And a brake operating element input point for setting a first predetermined backward limit, a motor linear motion means input point for connecting to the motor direct acting means and setting a second predetermined backward limit, and a master piston pushing member of the master cylinder A master cylinder output point to be coupled to the intermediate portion of the floating lever, one end portion, and the other end portion individually, The master cylinder serving as an action point with one of the motor linear motion means input points as a power point and the other of the motor linear motion means input to the first predetermined backward limit or the second predetermined backward limit as a fulcrum. A vehicular brake device characterized in that an input of the power point can be transmitted to an output point.   The motor linear motion means is constituted by a crank mechanism, and a connecting rod provided in the crank mechanism is pivotally connected to the input selection means, and the brake operating element input point of the input selection means and the motor linear motion means input point The crank angle of the crank mechanism at a non-operation initial position regulated by the first predetermined backward limit and the second predetermined backward limit is set to 90 degrees to 100 degrees before top dead center. Item 4. The vehicle brake device according to Item 1.   The motor linear motion means is constituted by a crank mechanism, and a connecting rod provided in the crank mechanism is pivotally connected to the input selection means, so that the brake operating element input point of the input selection means is at the first predetermined backward limit. 3. The vehicle brake device according to claim 1, wherein the crank angle of the crank mechanism at a position where the master piston of the master cylinder is fully stroked is set near a top dead center.   The power transmission means from the motor to the motor linear motion means is composed of a gear pair in which the drive gear provided on the motor side is a worm gear and the driven gear provided on the motor linear motion means side is a worm wheel gear. The vehicular brake device according to any one of claims 1 to 3.   The input selection means is configured as a simulator push rod configured as the input transmission member from the brake operator, and as the input transmission member from the brake operator, and the first of the brake operator input points. The stroke simulator which changes the stroke of the brake operator according to the input of the brake operator is provided with the relative distance with the reaction force piston which constitutes the predetermined retreat limit. The vehicle brake device according to claim 1.   The stroke simulator forms a hydraulic pressure chamber, and when the reaction force piston is restricted to the first predetermined backward limit, the hydraulic pressure chamber is opened to atmospheric pressure to allow a stroke simulating operation, and the reaction force 6. The vehicle brake according to claim 5, further comprising a shut-off valve that restricts the stroke simulating operation by making the hydraulic chamber oil tight when the piston moves forward by a predetermined amount from the first predetermined backward limit. apparatus.   At least the force for advancing the brake operator input point from the first predetermined backward limit by an input from the brake operator, the first predetermined backward movement of the brake operator input point by an input from the motor linear motion means. When the force that restrains the pressure is overcome, the floating lever acts on the master cylinder output point with the brake operating element input point as a fulcrum and the motor linear motion means input point as a fulcrum. The vehicle brake device according to any one of claims 1 to 6, further comprising an electronic control device for controlling the vehicle.

Images