JP2006306288A - Brake device for vehicle equipped with brake displacement variable adjustment means - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brake device for a vehicle under high operation reliability which can variably adjust the braking force generated by a friction brake device corresponding to a stepping amount of a pedal without causing loss of energy when the braking force is variably adjusted in the brake of a vehicle. <P>SOLUTION: In the brake device for the vehicle, a brake displacement variable adjustment means 16 which mechanically converts the stepping displacement of the brake pedal to the displacement of a piston 14 of a maser cylinder device, and adjustably converts a mutual relative magnitude is interposed between the brake pedal 10 and the piston 14 of a master cylinder device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle braking device, and more particularly to an improvement of a vehicle braking device related to a depression operation of a brake pedal.

When an electric vehicle with regenerative braking is equipped with a hydraulic control valve for anti-lock control in the hydraulic circuit of the braking device, the hydraulic control valve is controlled to release a part of the master cylinder hydraulic pressure. Therefore, the following Patent Document 1 describes that the generation of the friction braking torque is reduced by the amount of the braking torque corresponding to the regenerative braking torque with respect to the braking torque requested by the driver.
JP-A-7-336805

The brake pedal depression amount is detected by a pedal operation amount sensor, and the signal is sent to an electric control unit (ECU) of the vehicle, while the piston of the master cylinder device is driven by an electric motor. The following Patent Document 2 proposes to reduce the number of parts of the apparatus and avoid the reduction of energy efficiency and the generation of operation noise.
JP 2003-63367 A

  In electric vehicles and hybrid vehicles, the electric power recovered by regenerative braking can be effectively used for driving the vehicle, and therefore regenerative braking has been incorporated more significantly together with the improvement in performance. When a regenerative braking device is incorporated, it is natural that the braking force by the friction braking device should be reduced by the amount of braking force obtained by the regenerative braking device when braking the vehicle. This is done by releasing a part of the hydraulic pressure by a hydraulic control valve provided in the middle or by the anti-lock control hydraulic control valve as described in Patent Document 1. However, the master cylinder hydraulic pressure is usually a hydraulic pressure boosted (ie, pressurized) using energy other than the brake pedal depression force in response to the driver's depression of the brake pedal, and a part of the hydraulic pressure is lost. In the end, resulting in a reduction in fuel consumption.

  In this regard, if a part of the braking force requested by the driver by depressing the brake pedal is generated by the regenerative braking device, the operation of the master cylinder device may be reduced by the amount of the regenerative braking force. Therefore, as described in Patent Document 2, the amount of depression of the brake pedal is detected by a pedal operation amount sensor, and the signal is electrically processed by a vehicle electric control unit (ECU) to be a master. It is also conceivable to reduce the master cylinder hydraulic pressure in the computer control in the electric control device by utilizing the structure for operating the cylinder device. However, the operation of the braking device is extremely important for the operation of the vehicle, and there is a safety concern that it is electrically performed via the microcomputer.

  In view of the above circumstances, the present invention provides a brake that should be generated by a friction braking device with respect to the amount of pedal depression in a brake, such as when a regenerative braking force is obtained as a part of the braking force. It is an object of the present invention to provide a vehicular braking device that enables such adjustment without losing energy when the power is variably adjusted with high operational reliability.

  In order to solve the above-described problems, the present invention provides a vehicle brake device including a brake pedal and a master cylinder device having a piston that is displaced in response to depression of the brake pedal, and the brake pedal and the master And a brake displacement variable adjusting means which is interposed between pistons of a cylinder device and converts the depression displacement of the brake pedal into the displacement of the piston in a mechanically and adjustable manner relative to each other. A vehicle braking device is proposed.

  The braking displacement variable adjusting means is configured such that the displacement adjustment is fixed (locked) when energy for adjustment is not supplied, or the displacement of the piston with respect to the depression of the brake pedal is maximized. It may be like this.

  The brake displacement variable adjusting means may be adjusted by the judgment of the vehicle automatic control device, which is determined by the automatic control device according to the operation of the vehicle brake device other than the master cylinder device. The adjustment may be to reduce the displacement of the piston of the master cylinder device with respect to the stepping displacement. The other vehicle braking device may be a regenerative braking device.

  The braking displacement variable adjusting means is provided when the braking force corresponding to the depression of the brake pedal is generated only by the master cylinder device when the other braking device is operated together with the master cylinder device according to the depression of the brake pedal. Corresponding to the difference between the displacement of the piston of the master cylinder device and the displacement of the piston of the master cylinder device for generating the braking force by subtracting the braking force generated by another braking device from the braking force by the master cylinder device The displacement of the piston with respect to the depression of the brake pedal may be changed.

  In any of the above cases, a reactionless force booster may be interposed between the braking displacement variable adjusting means and the piston of the master cylinder device.

  In a vehicle braking device having a brake pedal and a master cylinder device having a piston displaced in response to depression of the brake pedal, the brake pedal is depressed between the brake pedal and the piston of the master cylinder device. If a braking displacement variable adjusting means is provided that converts the displacement into the displacement of the piston mechanically and adjusts the relative magnitude of each other, a regenerative braking force can be obtained as part of the braking force in braking the vehicle. When the braking force to be generated by the friction braking device is variably adjusted with respect to the pedal depression amount of the pedal, the displacement of the piston of the master cylinder device is mechanically adjusted with respect to the brake pedal depression displacement. It is possible to variably adjust the vehicle braking device without causing energy loss and to operate it with high operational reliability. Can.

  If the mechanical braking displacement adjusting means is fixed when the energy for adjusting is not supplied, the power for adjusting the braking displacement adjusting means due to some obstacle. Or, even if the air supply is not performed, the trouble caused thereby is that the brake displacement cannot be variably adjusted any more, and the operation confidence of the braking device is not impaired.

  Further, if the mechanical braking displacement variable adjusting means is in a state where the displacement of the piston with respect to the depression of the brake pedal is maximized when energy for adjustment is not supplied, the braking displacement can be changed due to some obstacle. Even if power or air is not supplied to adjust the adjusting means, the brake displacement can no longer be variably adjusted, but the brake displacement is maximized so that the piston displacement relative to the brake pedal depression displacement is maximized. Since the setting of the variable adjustment means is automatically changed, the braking device has a stronger braking force acting on the depression of the brake pedal, and alerts the occurrence of an abnormality on the safe side.

  In the structure in which the displacement of the piston of the master cylinder device is variably adjusted with respect to the depression of the brake pedal by the mechanical brake displacement variable adjusting means as described above, the brake displacement variable adjusting means is adjusted by the judgment of the vehicle automatic control device. If this is done, the braking performance of the vehicle can be varied in various ways by ensuring that the braking performance of the vehicle is secured and making the automatic control device make any automatic control determination.

  Further, in the structure in which the displacement of the piston is variably adjusted with respect to the depression of the brake pedal by the mechanical braking displacement variable adjusting means as described above, the braking displacement variable adjusting means is determined by the automatic control device except for the master cylinder device. As long as the displacement of the piston of the master cylinder device relative to the displacement of the brake pedal is reduced according to the operation of the other vehicle braking device, it is possible to ensure the braking performance of the vehicle and By reducing the displacement of the piston of the master cylinder device in advance according to the operation of the other vehicle braking device, energy loss is lost by wasting some of the hydraulic pressure that was consumed and pressurized by the master cylinder device. It is possible to avoid such a situation and to generate a sufficient braking force that is always necessary. This is particularly effective when a large regenerative braking force can be obtained as another braking force, such as an electric vehicle or a hybrid vehicle.

  When the braking displacement variable adjusting means is operated together with the master cylinder device in accordance with the depression of the brake pedal and another braking device is operated, the master cylinder when the braking force according to the depression of the brake pedal is generated only by the master cylinder device A brake pedal corresponding to the difference between the displacement of the piston of the device and the displacement of the piston of the master cylinder device for generating the braking force by subtracting the braking force generated by another braking device from the braking force by the master cylinder device If the displacement of the piston of the master cylinder device with respect to the stepping displacement of the master cylinder is variably adjusted, the braking force generated by other braking devices as in regenerative braking will change from time to time according to the operating state of the vehicle. However, the master cylinder device is always required in accordance with it, and it is accurately controlled to generate sufficient braking force. It can be.

  If a non-reaction force booster is interposed between the brake displacement variable adjusting means and the piston of the master cylinder device, the operation of the brake displacement variable adjusting means according to the fluctuation of the braking force generated by the other braking force generating means. Regardless of how the state changes, it is possible to uniformly maintain the correspondence between the depression and depression of the accelerator pedal and the effectiveness of the braking device with respect to the driver.

  FIG. 1 is a schematic view showing a vehicle braking apparatus according to one embodiment of the present invention.

  In the figure, 10 is a brake pedal, 12 is a master cylinder of the master cylinder device, and 14 is a piston of the master cylinder device. A brake displacement variable 16 is interposed between the brake pedal 12 and the piston 14 of the master cylinder device to convert the depression displacement of the brake pedal into the displacement of the piston 14 in a mechanically and adjustable manner relative to each other. Adjustment means. Reference numeral 18 denotes an input shaft of the brake displacement variable adjusting means 16, and 20 denotes an output shaft thereof. In this embodiment, a reactionless booster 22 is interposed between the braking displacement variable adjusting means 16 and the piston 14 of the master cylinder device. The structure of the mechanical braking displacement variable adjusting means 16 will be described in detail later with reference to FIGS.

  The reactionless booster 22 is shown in an illustrative manner so that its structure shows the functional principle more clearly. The actual structure of the valve port may be different from that shown in the figure, for example, the valve seat of the abutting valve port may be configured to be movable, not the slide type. The reactionless booster 22 includes a rigid disc-shaped front wall portion 24, a cylindrical bellows portion 26 extending from the center thereof, a rigid disc-shaped rear wall portion 28, and a front wall portion 24. And a diagram 30 that bisects the space enclosed between the rear wall portion 28 and the rear wall portion 28, a cylindrical valve seat 32 that extends along the bellows portion 26 from the central portion thereof, and a cylindrical valve seat 32. And a piston-like valve body 34 connected to the output shaft 20 of the braking displacement variable adjusting means 16 so as to slide along the axis thereof, and a master cylinder device connected to the cylindrical valve seat 32 at one end. And an output shaft 36 connected to the piston 14.

  The cylindrical valve seat 32 is formed with valve ports 38 and 40 at two positions along the axial direction thereof. In the state shown in the drawing, the valve port 38 is released from the overlap with the piston valve body 34 and opened. The valve port 40 overlaps with the piston valve body 34 and is closed. A vacuum from the vacuum pump 42 is introduced into the left chamber space of the diagram 30, and this vacuum is formed in a hole 44 formed in a flange portion formed at a connection portion of the output shaft 36 with the cylindrical valve seat 32. And is extended to a cylindrical space in the cylindrical valve seat 32. In the state shown in the figure, this vacuum further reaches the chamber space on the right side of the diagram 30 via the valve port 38. At this time, since the valve port 40 is closed by the piston piston valve body 34, the same vacuum acts on both the left and right sides of the diagram 30 in this state.

  When the output shaft 20 of the braking displacement variable adjusting means 16 is moved to the left in the drawing in accordance with the depression of the brake pedal 10 from this state, the valve port 38 is closed by the piston valve body 34, and the valve port 40 is Since it is released from the overlap with the valve body 34, atmospheric pressure acts on the right side of the diagram 30, and the diagram 30 is pushed by the differential pressure acting on both sides and displaced to the left in the figure. To do. The displacement of the cylindrical valve seat 32 to the left by the diagram 30 is that if it exceeds the displacement of the valve 34 to the left, the valve port 38 will be opened and the valve port 40 will be closed. Does not occur. Thus, the output shaft 36 is displaced to the left following the displacement of the valve 34 to the left, and the displacement to the left of the output shaft 36 is a vacuum regardless of the force for displacing the piston valve body 34 to the left. The master cylinder device is boosted up with no reaction force against the brake pedal in response to the depression of the brake pedal. The displacement of the piston valve body 34 with respect to the cylindrical valve seat 32 may be within a range in which the valve ports 38 and 40 are opened and closed. Therefore, relative displacement between the two exceeding the range is blocked by an appropriate stopper, Even when the supply of vacuum is stopped, boost-up cannot be obtained, but the piston 14 of the master cylinder device can be directly driven by the brake pedal 10. A return spring 46 exerts a reaction force against the depression of the brake pedal. In the reactionless booster 22, the reaction force due to the hydraulic pressure acting on the output shaft 36 is not transmitted to the input shaft 20. Accordingly, since the reaction force is directly exerted by the return spring 46 against the depression of the brake pedal, the driver can depress the depth of depression of the brake pedal regardless of the operating state of the brake displacement variable adjusting means 16. The reaction force determined according to

  A free piston 48 is provided in the master cylinder 12, and the oil pressurized in the front chamber between the piston 14 and the free piston 48 passes through the oil passages 50F, 52FL, 52FR, and the front left wheel wheel cylinder 54FL. The brake discs 56FL and 56FR are supplied to the front right wheel wheel cylinder 54FR to brake the front left wheel and the front right wheel. The oil pressurized in the rear chamber behind the free piston 48 in the master cylinder 12 is supplied to the wheel cylinder 62RL for the rear left wheel and the wheel cylinder 62RR for the rear right wheel through the oil passages 58R, 60RL, 60RR, and the brake disc. The rear left wheel and the rear right wheel are braked by compressing 64RL and 64RR.

  Hydraulic shutoff valves 66FL and 66FR for selectively shutting off the oil passages are provided in the middle of the oil passages 52FL and 52FR, and hydraulic shutoff valves for selectively shutting off the oil passages in the middle of the oil passages 60RL and 60RR. 68RL and 68RR are provided. The oil cylinders 52FL, 52FR are connected to the return oil path 72 via hydraulic cutoff valves 70FL, 70FR for selectively blocking the oil passages on the wheel cylinders 54FL, 54FR side from the hydraulic cutoff valves 66FL, 66FR of the oil passages 52FL, 52FR. The wheel cylinders 62RL, 62RR side of the hydraulic pressure cutoff valves 68RL, 68RR of 60RL, 60RR are connected to the return oil path 72 via hydraulic pressure cutoff valves 74RL, 74RR that selectively shut off the oil path.

  In addition to the master cylinder device, the hydraulic pressure pressurized by the hydraulic pump 76 is supplied to the wheel cylinders 54FL, 54FR, 62RL, and 62RR via an oil passage 80 including a hydraulic pressure supply control valve 78. Yes. Oil path 80 is connected to oil paths 60RL and 60RR, and is also connected to oil paths 52FL and 52FR via oil path 82. The operation of the hydraulic pump 76 is controlled by a vehicle electric control device 84 having a microcomputer, and the hydraulic cutoff valves 66FL, 66FR, 68RL, 68RR, 70FL, 70FR, 74RL, and 74RR are controlled by the electric control device 84. In combination with this, vehicle running stability control (VSC) for controlling the vehicle against spin and drift-out is performed.

  Reference numeral 86 denotes a hydraulic pressure relief control valve that selectively releases oil from the oil passage 80 toward the return oil passage 72, 88 is an oil reservoir, and 90 is a hydraulic accumulator. The operations of the hydraulic supply control valve 78 and the hydraulic relief control valve 86 are also controlled by the electric control device 84. One-way valves 92, 94, and 96 are provided in the middle of the oil passages 50F, 58R, and 82, respectively.

  The front left wheel, the front right wheel, the rear left wheel, and the rear right wheel have regenerative braking forces generated by the motor generators 98FL, 98FR, 98RL, and 98RR in addition to the friction braking forces by the wheel cylinders 54FL, 54FR, 62RL, and 62RR, respectively. The brakes are also applied. Each of these motor generators is connected to a vehicle battery not shown in the drawing via electric wiring not shown in the drawing and an inverter not shown in the drawing, and these inverters are electrically operated. By being controlled by the control device 84, the operation thereof is individually controlled by a control signal from the electric control device 84 as schematically shown in the figure.

  In the present invention, when the vehicle is braked only by friction braking by the master cylinder device, the master cylinder hydraulic pressure is shown by a solid line in FIG. 2 as the brake pedal (BP) stroke increases. When it is supposed to increase as shown, the braking force corresponding to the magnitude indicated by the shaded line in the figure is obtained by other braking means such as the regenerative braking device shown in FIG. When the braking force is reduced as shown by the broken line in the figure, the master cylinder in which the piston of the master cylinder device is displaced in response to the depression of the brake by the device shown as the variable braking displacement adjusting means 16 in FIG. (MC) Stroke is reduced by ΔS to reduce the master cylinder hydraulic pressure generated by the master cylinder device. That.

  FIG. 3 is a schematic view showing a first embodiment of the braking displacement variable adjusting means 16 schematically shown by a rectangular block in FIG. In FIG. 3, shafts 18 and 20 respectively correspond to the input shaft 18 and the output shaft 20 of the braking displacement variable adjusting means 16 in FIG. In this case, threaded grooves 100 and 102 extending in directions opposite to each other are cut at the ends of the shafts 18 and 20 that are aligned and opposed to each other, and are received so as to cover these shaft ends. The inside of the sleeve 104 is fitted in the thread grooves 100 and 102, and a large number of balls 106 that can slide relative to each other are received in a hemispherical recess formed on the inner surface of the sleeve 104. Is provided.

  The sleeve 104 is rotated about the shafts 18 and 20 in response to a gear 108 provided at one end thereof meshing with a pinion 110 and the pinion being driven to rotate in one direction or the other direction by the motor 112. Are rotated in one direction or in the opposite direction. With this configuration, the axial movement of the input shaft 18 according to the depression of the brake pedal is appropriately reduced according to the rotation of the sleeve 104 and converted into the axial movement of the output shaft 20.

  In this case, the shafts 18 and 20 are moved closer to or away from each other in accordance with the rotation of the sleeve 104, but the sleeve 104 cannot be rotated by the relative axial movement of the shafts 18 and 20. When a failure occurs in the control system of the motor 112 and the motor 112 does not operate, the brake displacement variable adjustment by the brake displacement variable adjusting means cannot be performed thereafter. However, the master cylinder device is operated by depressing the brake pedal. The function of braking the vehicle is not impaired.

  FIG. 4 is a schematic diagram showing a second embodiment of the variable braking displacement adjusting means 16. Also in FIG. 4, the shafts 18 and 20 respectively correspond to the input shaft 18 and the output shaft 20 of the braking displacement variable adjusting means 16 in FIG. In this case, rack teeth 114 and 116 are cut on the opposite surfaces of the shafts 18 and 20 in parallel with each other, and a pinion 118 is inserted between the teeth. . The pinion 118 is rotationally driven by a worm gear 120 as partially shown in perspective view in the figure, and the worm gear 120 has a worm 122 meshing with it in one direction or the opposite direction by an electric motor 124. By being rotationally driven in this direction, it is rotationally driven in one direction or in the opposite direction.

  Also in this case, the worm gear 120 can be driven from the worm 122 side, but conversely, since the worm 122 cannot be driven from the worm gear 120 side, some trouble occurs in the control system of the electric motor 124. When the electric motor 124 stops operating, the variable adjustment of the braking displacement by the braking displacement variable adjusting means cannot be performed thereafter, but the function of braking the vehicle by operating the master cylinder device by depressing the brake pedal is not impaired.

  FIG. 5 is a schematic view showing a third embodiment of the variable braking displacement adjusting means 16. Also in FIG. 5, the shafts 18 and 20 respectively correspond to the input shaft 18 and the output shaft 20 of the braking displacement variable adjusting means 16 in FIG. In this case, the spaced apart and proximal ends of the shafts 18 and 20 are located at different positions along the long groove 128 of the lever member 130 that rotates about the pivot 126 by engaging the pivot 126 with the long groove 128. It is connected to the pivotable. Since the shafts 18 and 20 are restricted to move in the substantially axial direction as understood from FIG. 1, the position of the lever member 130 in the vertical direction in the drawing is maintained substantially constant. On the other hand, the pivot 126 is fixed in the left-right direction in the figure and adjusted up and down by an appropriate linear actuator not shown in the figure.

  According to this configuration, when the pivot 126 is displaced downward in the drawing along the long groove 128, the ratio of the axial displacement of the shaft 20 to the axial displacement of the shaft 18 is reduced. Also in this case, the above-described linear actuator is appropriately designed so that when it is not activated due to some failure, the pivot 126 remains in its position, and the braking displacement by the braking displacement variable adjusting means is set. However, the function of braking the vehicle by operating the master cylinder device by depressing the brake pedal can be kept intact.

  FIG. 6 is a schematic view showing a fourth embodiment of the variable braking displacement adjusting means 16. Also in FIG. 6, the shafts 18 and 20 correspond to the input shaft 18 and the output shaft 20 of the braking displacement variable adjusting means 16 in FIG. 1, respectively. In this case, the ends of the shafts 18 and 20 that are aligned and opposed in the axial direction are brought into the engagement relationship between the cylinder and the piston. That is, a cylinder 132 is attached to the end of the shaft 18, and the end of the shaft 20 is connected to a piston 134 that slides inside the cylinder 132. The piston 134 is urged toward the left in the figure by a compression coil spring 136 disposed in the cylinder chamber on the right side of the figure. Then, compressed air is selectively introduced into a cylinder chamber 138 on the left side of the piston via a port 140 from a compressed air source (not shown).

  According to this configuration, as the piston 134 is displaced rightward in the drawing against the action of the compression coil spring 136 by the compressed air introduced into the cylinder chamber 138, the input shaft 18 is depressed by the depression of the accelerator pedal. In the drawing, the leftward displacement is reduced in the drawing of the shaft 20 with respect to the leftward displacement, and the degree of increase in the master cylinder hydraulic pressure with respect to the accelerator pedal depression amount is reduced.

  In this case, when a suitable compressed air source such as an air pump (not shown in the figure) does not operate due to some failure and compressed air cannot be obtained, the variable adjustment of the braking displacement by the braking displacement variable adjusting means can be performed thereafter. At the same time, since the piston 134 is pushed to the leftmost end in the cylinder chamber by the action of the compression coil spring 136, the displacement of the output shaft 20 to the left with respect to the input shaft 18 is maximized, and the brake displacement variable adjusting means is the brake pedal. The displacement of the piston of the master cylinder device with respect to the stepping displacement is maximized.

  FIG. 7 is a schematic view showing a fifth embodiment of the braking displacement variable adjusting means 16. Also in FIG. 7, the shafts 18 and 20 correspond to the input shaft 18 and the output shaft 20 of the braking displacement variable adjusting means 16 in FIG. 1, respectively. Also in this case, the ends of the shafts 18 and 20 that are aligned and opposed in the axial direction are brought into the engagement relationship between the cylinder and the piston, and the cylinder 142 is attached to the end of the shaft 18, The end of the shaft 20 is connected to a piston 144 that slides inside the cylinder 142. The piston 144 is urged toward the left in the figure by a compression coil spring 146 disposed in the cylinder chamber on the right side in the figure. A vacuum is selectively introduced into a cylinder chamber 148 on the right side of the piston via a port 150 from a vacuum source not shown in the drawing.

  According to such a configuration, as the piston 144 is displaced to the right in the figure against the action of the compression coil spring 146 by the vacuum introduced into the cylinder chamber 148, the diagram of the input shaft 18 due to the depression of the accelerator pedal. , The leftward displacement is reduced in the drawing of the shaft 20 with respect to the leftward displacement, and the degree of increase in the master cylinder hydraulic pressure with respect to the accelerator pedal depression amount is reduced.

  Also in this case, when a suitable vacuum source such as a vacuum pump not shown in the drawing does not operate due to some failure and a vacuum cannot be obtained, the variable adjustment of the braking displacement by the braking displacement variable adjusting means is thereafter performed. At the same time, the piston 144 is pushed to the leftmost end in the cylinder chamber by the action of the compression coil spring 146, so that the displacement of the output shaft 20 to the left with respect to the input shaft 18 becomes maximum, and the brake displacement variable adjusting means The displacement of the piston of the master cylinder device with respect to the depression of the pedal is maximized.

  FIG. 8 is a flowchart showing a mode in which the braking displacement variable adjusting means 16 is controlled by the electric control device 84. The control according to the flowchart may be repeated at a cycle of several tens to several hundreds of milliseconds as part of automatic vehicle operation control by the electronic control device 84 during operation of the vehicle with the vehicle operation switch closed.

  When the control is started, various signals necessary for the control are read in step 10. In this case, in particular, the vehicle speed, the acceleration or deceleration of the vehicle, the brake pedal stroke Sb, the steering angle, etc. may be read in order to control the variable braking displacement adjusting means 16.

  Control then proceeds to step 20, where the master cylinder oil pressure when the braking force corresponding to the brake pedal stroke Sb is generated only by friction braking based on the information obtained from the signal read above is the full master cylinder oil pressure. A regenerative braking force Fbr that is obtained as Pmt and that can be generated based on the driving state of the vehicle is calculated at the same time.

  Next, the control proceeds to step 30, and it is determined whether or not the value of the regenerative braking force Fbr calculated above is greater than or equal to a predetermined lower limit value Fbo. The lower limit value Fbo is a comparatively small value that does not reach the control for adjusting the braking displacement variable adjusting means 16 in a state where the value of the regenerative braking force Fbr calculated above is lower than that. is there. If the answer is no (N), the control of this time is returned as it is, and the brake displacement variable adjustment control is not performed. If the answer is yes (Y), control continues to step 40.

  In step 40, the regenerative braking force Fbr calculated above is converted into a master cylinder hydraulic pressure difference ΔPm.

  Next, control proceeds to step 50, where the execution master cylinder hydraulic pressure Pme is obtained as a value obtained by subtracting ΔPm from Pmt as the hydraulic pressure to be generated by the master cylinder.

  Next, the control proceeds to step 60, and the stroke of the piston of the master cylinder corresponding to the execution master cylinder hydraulic pressure Pme is obtained as the master cylinder stroke Sc.

  Subsequently, the control proceeds to step 70, and the stroke reduction ΔS to be executed by the braking displacement variable adjusting means 16 is calculated by subtracting Sc calculated above the stroke Sb of the brake pedal depression by the driver.

  Then, the control proceeds to step 80 where the brake displacement variable adjusting means 16 is operated to reduce the stroke of the piston of the master cylinder device by the stroke reduction amount ΔS with respect to the brake pedal stroke.

  FIG. 9 is a graph showing the control performed in accordance with the flowchart of FIG. 8 in the above manner in the graph of the master cylinder hydraulic pressure with respect to the brake pedal (BP) stroke or the master cylinder (MC) stroke shown in FIG. In the figure, the solid line shows the relationship between the brake pedal stroke and the master cylinder hydraulic pressure when the braking force requested by the driver's depression of the brake pedal is all performed by friction braking. On the other hand, the broken line 1 in the figure represents the master cylinder stroke when the value of the regenerative braking force Fbr calculated in step 20 in FIG. 8 is relatively large and the friction braking force can be reduced considerably correspondingly. The relationship of master cylinder oil pressure is shown. Similarly, the broken line 2 in the figure indicates the master cylinder stroke when the value of the regenerative braking force Fbr calculated in step 20 in FIG. 8 is relatively small and the friction braking force is not reduced as much as the left. And the relationship between the master cylinder hydraulic pressure. 1 and 2 attached to Pmt, ΔPmt, Sb, Sc, and ΔS in the figure are 2 when the friction braking force obtained by subtracting the braking force due to regenerative braking from the total braking force is as indicated by the broken line 1 or 2. An example of a braking point in each of the two examples is shown. It will be clear that FIG. 9 shows in contrast to the flowchart of FIG.

  While the present invention has been described in detail with respect to several embodiments thereof, it will be apparent to those skilled in the art that various modifications can be made to these embodiments within the scope of the present invention. .

BRIEF DESCRIPTION OF THE DRAWINGS Schematic which shows the brake device for vehicles by this invention about one embodiment. The graph which illustrates the aspect in which the master cylinder stroke corresponding to a pedal stroke may be reduced by parallel implementation of regenerative braking. Schematic which shows 1st embodiment of a braking displacement variable adjustment means. Schematic which shows 2nd embodiment of a braking displacement variable adjustment means. Schematic which shows 3rd embodiment of a braking displacement variable adjustment means. Schematic which shows 4th Embodiment of a braking displacement variable adjustment means. Schematic which shows 5th embodiment of a braking displacement variable adjustment means. The flowchart which shows the aspect by which a braking displacement variable adjustment means is controlled by an electric control apparatus. The figure which represented the control performed according to the flowchart of FIG. 8 in the graph of a brake pedal stroke or a master cylinder troke versus master cylinder oil pressure.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Brake pedal, 12 ... Master cylinder, 14 ... Piston, 16 ... Braking displacement variable adjustment means, 18 ... Input shaft, 20 ... Output shaft, 22 ... No reaction force booster, 24 ... Front wall part, 26 ... Bellows part, 28 ... rear wall part, 30 ... diagram, 32 ... cylindrical valve seat, 34 ... piston valve body, 36 ... output shaft, 38, 40 ... valve port, 42 ... vacuum pump, 44 ... hole, 46 ... return spring, 48 ... Free piston, 50F, 52FL, 52FR ... Oil passage, 54FL, 54FR ... Wheel cylinder, 56FL, 56FR ... Brake disc, 58R, 60RL, 60RR ... Oil passage, 62RL, 62RR ... Wheel cylinder, 64RL, 64RR ... Brake disc, 66FL, 66FR, 68RL, 68RR, 70FL, 70FR ... Hydraulic cutoff valve, 72 ... Return oil passage, 74RL, 74RR Hydraulic shut-off valve, 76 ... hydraulic pump, 78 ... hydraulic supply control valve, 80, 82 ... oil passage, 84 ... electric control device, 86 ... hydraulic relief control valve, 88 ... oil reservoir, 90 ... hydraulic accumulator, 92,94 96 ... One-way valve, 98FL, 98FR, 98RL, 98RR ... Motor generator, 100, 102 ... Screw groove, 104 ... Sleeve, 106 ... Ball, 108 ... Gear, 110 ... Pinion, 112 ... Electric motor, 114, 116 ... Rack teeth, 118 ... pinion, 120 ... worm gear, 122 ... worm, 124 ... electric motor, 126 ... axial, 128 ... long groove, 130 ... lever member, 132 ... cylinder, 134 ... piston, 136 ... compression coil spring, 138 ... cylinder Chamber, 140 ... Port, 142 ... Cylinder, 144 ... Piston, 146 ... Compression coil spring, 148 ... Cylinder chamber, 15 ... port

Claims (8)

  A vehicle brake device having a brake pedal and a master cylinder device having a piston that is displaced in response to depression of the brake pedal, the brake device being interposed between the brake pedal and the piston of the master cylinder device. A braking apparatus for a vehicle, comprising: a braking displacement variable adjusting means for converting a pedal depression displacement into a displacement of the piston mechanically and so as to be capable of adjusting a relative magnitude of each other.   The vehicular braking apparatus according to claim 1, wherein the brake displacement variable adjusting means is fixed when displacement adjustment energy is not supplied.   2. The vehicle brake according to claim 1, wherein when the energy for adjustment is no longer supplied, the brake displacement variable adjustment means maximizes the displacement of the piston with respect to the depression of the brake pedal. apparatus.   The vehicular braking apparatus according to any one of claims 1 to 3, wherein the braking displacement variable adjusting means is adjusted by judgment of an automatic control apparatus for a vehicle.   The brake displacement variable adjusting means is adjusted to reduce the displacement of the piston of the master cylinder device relative to the depression of the brake pedal in accordance with the operation of a vehicle brake device other than the master cylinder device according to the judgment of the automatic control device. The vehicle braking device according to claim 4.   6. The vehicle braking device according to claim 5, wherein the other vehicle braking device is a regenerative braking device.   The braking displacement variable adjusting means generates a braking force according to depression of the brake pedal only by the master cylinder device when the other braking device is operated together with the master cylinder device according to depression of the brake pedal. The piston of the master cylinder device for generating the braking force generated by subtracting the braking force generated by the other braking device from the displacement of the piston of the master cylinder device when the master cylinder device is generated. The vehicular braking apparatus according to claim 5 or 6, wherein a displacement of the piston with respect to a depression of the brake pedal is changed corresponding to a difference in displacement of the brake pedal. The vehicular braking apparatus according to any one of claims 1 to 7, wherein a non-reaction force booster is interposed between the braking displacement variable adjusting means and the piston of the master cylinder device.

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