JP5161327B2 - Brake control device - Google Patents

Description

  The present invention relates to a vehicle brake control device, and more particularly to a brake-by-wire technology.

  Conventionally, a technique described in Patent Document 1 has been disclosed as a brake-by-wire system (hereinafter referred to as a BBW system). This publication has a configuration in which a brake is operated by supplying brake fluid accumulated in an accumulator to a wheel cylinder. With this configuration, it is possible to quickly supply the braking force necessary for normal time to the wheel cylinder by setting the pressure of the brake fluid accumulated in the accumulator as high as possible.

JP 2000-168536 A

  In the above-mentioned conventional BBW system, a stroke simulator is provided as a configuration that secures the driver's brake pedal stroke and further gives the driver a feeling of pedal effort. This stroke simulator is arranged integrally with the master cylinder or in the vicinity of the master cylinder. In other words, even though the booster such as a negative pressure booster has been eliminated by adopting the BBW system, a separate stroke simulator is placed in that space, which hinders space saving and restricts the layout in the engine room. Has occurred.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a brake control device capable of improving the degree of freedom of layout in an engine room.

In order to achieve the above object, in the brake unit of the present invention, a master cylinder as a first hydraulic pressure source that generates hydraulic pressure by a driver's brake pedal operation and a wheel cylinder that generates braking force on each wheel are connected. A brake unit provided on a pipe, wherein the brake unit includes a first port connected to the master cylinder formed on an upper surface of the housing via a pipe, and the wheel cylinder formed on the upper surface of the housing. And a second port connected via a pipe, a pump provided in the housing, a motor attached to the first side surface of the housing and driving the pump to rotate, and moving by a driver's brake pedal operation A stroke simulator for storing the brake fluid in the master cylinder, and the stroke simulator Data is between the top surface and the first imaginary line parallel to the street the upper surface of the motor rotation shaft of the motor in the first aspect, seen from the third side face side which is formed continuously to the first side surface When the stroke simulator and a part of the motor overlap, are biased to one side of the second imaginary line that passes through the motor rotation axis and orthogonal to the first imaginary line, and when viewed from the upper surface side The stroke simulator and a part of the motor are attached at a position where they overlap .

  Therefore, the configuration around the master cylinder can be made compact, and the degree of freedom in layout in the engine room can be improved.

It is a system diagram showing a system configuration of brake-by-wire control to which the brake control device of Example 1 is applied. FIG. 3 is a control block diagram illustrating a configuration of a control unit according to the first embodiment. It is a circuit diagram showing the outline of the brake control device in Example 1. It is a perspective view showing the appearance of brake unit H / U of Example 1. It is the front view seen from the motor side of the brake unit H / U of Example 1. FIG. It is the side view seen from the connector side of the brake unit H / U of Example 1. FIG. 4 is a perspective view illustrating only various electronic components and an oil passage in the first unit H1 of the first embodiment. It is a figure showing the fragmentary sectional view in brake unit H / U of Example 1. FIG. It is a figure showing the fragmentary sectional view in brake unit H / U of Example 2. FIG.

  Hereinafter, the best mode for realizing the brake control device of the present invention will be described based on Example 1 shown in the drawings.

  FIG. 1 is a system diagram illustrating the overall configuration of the brake control device according to the first embodiment. A rod 1 a is connected to the brake pedal 1 operated by the driver, and is connected to a piston in the master cylinder 3. Further, the rod 1a is provided with a pedal force sensor 100 for detecting a driver's pedal force and a stroke sensor 101 for detecting a brake pedal stroke amount.

  The master cylinder 3 is provided with a reservoir tank 2, and is configured to ensure a stable stroke amount of the rod 1a even if the amount of brake fluid varies. The master cylinder 3 includes oil passages 31 and 32 that are pipes for the master cylinder that supply and discharge brake fluid in the master cylinder to and from the brake unit H / U, and a hydraulic pressure source in the brake unit H / U. An oil passage 36 is provided as a pipe for a reservoir tank for intake of the gear pump 10 or for returning the brake fluid when the wheel cylinder W / C is depressurized to the reservoir tank 2. Note that two master pipes are actually provided because a tandem master cylinder is used. In addition, oil passages 33, 33a, 34, and 34a, which are pipes for the wheel cylinder that supplies and discharges brake fluid, are provided between the brake unit H / U and the wheel cylinder W / C that generates braking force on each wheel. It has been.

  The brake unit H / U is connected to the first ports H11 and H12 connected to the oil passages 31 and 32 which are pipes for the master cylinder and the oil passages 33, 33a, 34 and 34a which are pipes for the wheel cylinders. Second ports H13, H14, H15, and H16 and a third port H17 that connects to an oil passage 36 that is a pipe for a reservoir tank are provided.

  The BBW controller CU includes a brake unit H / W based on sensor signals input from the pedal force sensor 100, the stroke sensor 101, the wheel speed sensor 102 for detecting the rotational speed of the wheel, and various hydraulic pressure sensors in the brake unit H / U. Various electromagnetic valves and motors 50 in U are controlled. The hydraulic pressure sensor and the electromagnetic valve will be described later.

  FIG. 2 is a control block diagram showing the configuration in the BBW controller CU. In the BBW controller CU, a target cylinder hydraulic pressure calculation unit CU1 that calculates a target wheel cylinder pressure based on an operation state detected by a pedal force sensor 100 and a stroke sensor 101 that detect a driver's brake pedal operation state, and the like A system activation determination unit CU2 is provided that determines whether or not the brake-by-wire system should be activated based on the ignition signal 103 and the like.

  When the target cylinder hydraulic pressure is calculated by the target cylinder hydraulic pressure calculation unit CU1, the motor drive control unit CU11 that controls the drive of the motor 50 for the gear pump 10 and the valve states of the later-described in valves 13, 13a, 14, and 14a are controlled. Various command signals are output to the in-valve control unit CU12 that performs control and the out-valve control unit CU13 that controls the valve states of the later-described out valves 15, 15a, 16, and 16a.

  When the system activation determining unit CU2 determines that the system is activated, a shutoff valve control unit CU21 that controls the valve state of the shutoff valves 11 and 12 described later, and a shut valve control that controls the valve state of the shut valve S1 described later. Various command signals are output to the unit CU22. Note that the system activation determination unit CU2 may activate the system not only with the ignition signal but also with a signal from a brake switch, a door lock release signal, or the like, and is not particularly limited. The shut valve control unit CU22 basically operates based on a signal from the system activation determination unit CU2, but may be controlled by other control elements and is not particularly limited.

  FIG. 3 is a circuit diagram illustrating a hydraulic circuit in the brake unit H / U in the brake control device according to the first embodiment. Hereinafter, the circuit diagram of FIG. 3 will be described.

[Brake unit oil passage configuration]
The wheel cylinder FL of the left front wheel is connected to the master cylinder 3 via an oil passage 33, an oil passage 311, an oil passage 310 and an oil passage 31. The wheel cylinder FR of the right front wheel is connected to the master cylinder 3 through an oil passage 34, an oil passage 321, an oil passage 320 and an oil passage 32. The wheel cylinder RL of the left rear wheel is connected to the master cylinder 3 through an oil passage 33a, an oil passage 311a, an oil passage 310, and an oil passage 31. The wheel cylinder RR of the right rear wheel is connected to the master cylinder 3 through an oil passage 34a, an oil passage 321a, an oil passage 320, and an oil passage 32.

  The oil passages 31 and 32 are provided with normally-open shut-off valves 11 and 12 (corresponding to a first switching valve), respectively. The shut-off valves 11 and 12 are normally closed during braking and opened during a failure. By using a normally open valve, the valve automatically opens when the electrical system fails, and a manual brake is secured. A branch oil passage 32 a is provided on the oil passage 32 between the master cylinder 3 and the shutoff valve 12. The branch oil passage 32a is provided with a stroke simulator SS (corresponding to a liquid absorber) that stores the brake fluid of the master cylinder 3 via a normally closed shut valve S1 (corresponding to a second switching valve).

  This stroke simulator SS is characterized in that it is arranged not on the master cylinder 3 side but on the brake unit H / U side. The brake control device of the first embodiment does not include an accumulator as shown in the prior art. Therefore, by installing the stroke simulator SS in an advantageous space, it is possible to further secure a space near the master cylinder. In addition, an existing master cylinder can be applied, which can contribute to cost reduction. Details of the stroke simulator SS will be described later.

  A hydraulic pressure sensor 21 is provided on the oil passage 31. A hydraulic pressure sensor 22 a is provided on the oil passage 32. Further, hydraulic pressure sensors 23, 23a, 24, 24a are provided on the oil passages 33, 33a, 34, 34a connected to the wheel cylinders of the respective wheels.

  The gear pump 10 is disposed between the oil passage 35 on the pump suction side and the discharge oil passage 370 on the pump discharge side. The oil passage 35 is connected to the reservoir tank 2 through an oil passage 36, and the discharge oil passage 370 is connected to the oil passage 43 through a relief valve 19, and oil is supplied through check valves 17 and 18 for backflow prevention. Connected to paths 37 and 38.

  A downstream side of the oil passage 37 from the gear pump 10 is connected to an oil passage 37a. On the oil passage 37a, in-valves 13 and 13a which are normally open type proportional control valves are provided. One end of the oil passage 37a is connected to the oil passage 311 and the other end is connected to the oil passage 311a. Similarly, the downstream side of the oil passage 38 from the gear pump 10 is connected to the oil passage 38a. The oil passage 38a is provided with in-valves 14 and 14a which are normally open type proportional control valves. One end of the oil passage 38a is connected to the oil passage 321 and the other end is connected to the oil passage 321a.

  An oil path 41 connected to the oil path 36 is provided between the oil path 311 and the oil path 33. On the oil passage 41, an out valve 15 which is a normally closed type proportional control valve is provided. An oil path 42 connected to the oil path 36 is provided between the oil path 321 and the oil path 34. An out valve 16 that is a normally closed type proportional control valve is provided on the oil passage 42. An oil passage 41a connected to the oil passage 36 is provided between the oil passage 311a and the oil passage 33a. An out valve 15a, which is a normally closed proportional control valve, is provided on the oil passage 41a. An oil passage 42a connected to the oil passage 36 is provided between the oil passage 321a and the oil passage 34a. An out valve 16a, which is a normally closed proportional control valve, is provided on the oil passage 42a.

  The brake unit H / U of the present embodiment has a configuration in which one housing is provided with one pump and a control valve for supplying hydraulic pressure for four wheels from the pump is mounted. Is not limited. For example, two groups of front wheel two wheel cylinders FR-FL and two rear wheel cylinders RL-RR each have a brake unit H / U, and either one of the brake units H / U It is good also as a structure carrying a stroke simulator. Further, two groups of two front wheels and two rear wheels may be configured.

  Further, one of the groups of the front wheels FR and FL and the rear wheels RR and RL may be configured by a hydraulic brake unit H / U, and the other may be configured by an electric brake.

[Normal brake control]
Next, the normal control time during which brake-by-wire control is performed will be described. The left front and rear wheels and the right front and rear wheels have basically the same function, so the left front and rear wheels will be described. When the brake-by-wire system is activated, the shut valve S1 is opened and the shut off valves 11 and 12 are closed. When the brake pedal 1 is depressed, the brake fluid in the master cylinder 3 is supplied from the oil passage 32 to the oil passage 32a and stored in the stroke simulator SS via the shut valve S1. The operation in the stroke simulator SS will be described later. At this time, the target wheel cylinder hydraulic pressure is calculated based on the pedal stroke and the depression force, and a current is supplied to the motor 50.

  When the gear pump 10 is driven in this state, the brake fluid pressure is supplied from the oil passage 37 to the oil passage 37 a via the check valve 17. Further, the brake fluid pressure is supplied from the oil passages 33 and 33a to the wheel cylinders W / C (FL and RL) via the in-valves 13 and 13a on the oil passage 37a, and is increased to a desired fluid pressure. On the other hand, when reducing the wheel cylinder pressure, the driving of the gear pump 10 is stopped, the out valves 15 and 15a are opened, and the hydraulic pressure of the wheel cylinder W / C is caused to flow from the oil passages 41 and 41a to the oil passage 36 to thereby reduce the reservoir. Reflux to tank 2.

[Fail control]
At the time of failure, the current supply to all the solenoid valves is cut off. Then, the shut valve S1 is closed and the shut off valves 11 and 12 are opened. When the brake pedal 1 is depressed, the brake fluid in the master cylinder 3 is directly supplied to the wheel cylinder W / C via the oil passage 31 → the oil passage 310 → the oil passages 311, 311a → the oil passages 33, 33a. At this time, it becomes possible to supply the brake fluid pressure that has passed only the shut-off valves 11 and 12, and the brake fluid pressure can be generated with a relatively small pedal effort. Even when the in-valves 13 and 13a are in the open state, the oil passage 37a and the oil passage 37 are closed by the check valve 17, so that the brake fluid pressure does not flow.

(About the brake unit)
4 is a perspective view showing an appearance of the brake unit H / U, FIG. 5 is a front view seen from the motor side, and FIG. 6 is a side view seen from the connector side. Furthermore, for the sake of explanation, FIG. 7 shows a perspective view showing only various electronic components and oil passages in the first unit H1, and FIG. 8 shows a partial sectional view.

  The brake unit H / U includes a first unit H1 made of an aluminum block, a second unit H2 made of a resin material, and a cover member H3 made of a resin material. The first unit H1 is provided with a first side face H101 to which the motor 50 and the stroke simulator SS are attached, a second side face H102 facing the first side face H101, an upper face H103 to which a brake pipe is attached, and a lower face insulator ISU. It has a lower surface H104, a side surface H105 on the side where the stroke simulator SS is biased, and a side surface H106 on the side where the connector H22 of the second unit H2 is provided.

  A motor 50, a stroke simulator SS, and a side insulator ISS are attached to the first side face H101. The motor 50 is provided with four bolt fixing hubs 501 to 504 at substantially equal intervals. The hubs 501 to 504 are attached in a state where a straight line P1 connecting the hub 501 and the hub portion 503 is offset from a direction perpendicular to the vertical axis P2 when mounted on the vehicle. As a result, the hubs 501 to 504 can be made as large as possible, and the space of the first side face H101 is effectively used.

  Front-side insulators ISS are provided at both ends of the first side face H101 when in-vehicle. The front-side insulator ISS is composed of a fixed shaft ISS1 protruding from the first unit H1 in parallel with the motor shaft, and a rubber ISS2 as an elastic member attached so as to surround the outer periphery of the fixed shaft ISS1. The bottom surface of the rubber ISS2 is in direct contact with the first side surface H101 to effectively reduce vibration.

  The stroke simulator SS has a cylindrical shape, and is attached to a position that is above the horizontal axis P3 that passes through the motor rotation axis G1 when mounted on the vehicle and that is biased to one side relative to the vertical axis P2. Thereby, it arrange | positions efficiently in the remaining space which attached the circular motor 50 with respect to the 1st side surface H101 which is a rectangle.

  As shown in the partial cross-sectional view of FIG. 8, the stroke simulator SS is cylindrical and has an outer cylinder SS1 fixed to the first unit H1 and a substantially conical first fixed to the bottom surface SS1a of the outer cylinder SS1. The rubber member SS2, the first spring SS3 fixed between the spring holding portion SS1b of the outer cylinder SS1 and the spring holding portion SS4a of the inner cylinder SS4, the inner cylinder SS4, the bottom surface SS4b of the inner cylinder SS4, and the piston SS6 Liquid tight between the second spring SS5 fixed between the step SS6a, the piston SS6, the second rubber member SS7 fixed to the tip of the piston SS6, and the inner periphery of the piston SS6 and the outer cylinder SS1 It is composed of a seal member SS8 that slides on the surface.

  When brake fluid is supplied from the master cylinder 3 into the stroke simulator SS, the bottom surface of the piston SS6 is pushed and moves to the left in FIG. 8 against the elastic force of the second spring SS5. Then, the inner cylinder SS4 and the second rubber member SS7 fixed to the tip of the piston SS6 come into contact with each other, and the inner cylinder SS4 and the piston SS6 are united against the elastic force of the first spring SS3 in FIG. Move to the left. The inner cylinder SS4 and the first rubber member SS2 are brought into contact with each other with an elastic force, thereby giving the driver a stepping on the brake pedal. Further, by using the elastic force of the two springs, it is possible to give different footing depending on the stroke amount of the brake pedal 1. Specifically, it is configured such that as the amount of depression increases, the amount of depression increases. As for the specific action of the stroke simulator, the contents disclosed in Japanese Patent Application Laid-Open No. 2004-330966 can be applied. For example, the configuration may be such that the reaction force against the pedaling force can be varied by making it possible to change the compression amount of the spring by a position adjusting mechanism using a screw according to the driver's preference.

  The second side face H102 facing the first side face H101 is provided with a plurality of mounting holes H102a to which electronic parts such as the above-described in-valve, out-valve, and hydraulic pressure sensor are attached (see FIG. 8). After these electronic components are inserted into the mounting hole H102a, the periphery of the mounting hole H102a is crushed and fixed by caulking. In addition to crimping, an electronic component may be press-fitted into the mounting hole H102a, or may be fixed by screwing or the like, and is not particularly limited. The shut valve S1 is attached at a position where the stroke simulator SS is projected onto the second side face H102.

  Further, the second unit H2 is attached to the second side face H102 so as to cover various electronic components. As shown in the front view of FIG. 5, the second unit H2 includes a connection port H22 that connects to a connector in which a power supply, various sensor signals, CAN communication lines, and the like are integrated, and a support portion H21 that supports the connection port H22. Is provided. When the brake unit H / U is mounted on a vehicle, various pipes are concentrated in the upper part of the unit, and brackets and motors for fixing support are arranged below and in front of the unit. Wiring is taken out via a connector. At this time, considering the ease of connection of the connector and the like, the support portion H21 is provided on the side surface opposite to the side surface on which the stroke simulator SS is biased. Therefore, the stroke simulator SS, which is a protrusion, does not become a hindrance factor when the connector is connected.

  As shown in the side view of FIG. 6, a substrate K1 is attached to the second unit H2. The substrate K1 is electrically connected to the motor 50, each hydraulic pressure sensor, and each solenoid valve coil. A CPU, ROM, RAM, and the like are attached to the substrate K1, and configured as a control unit CU. In this way, various electronic components are arranged side by side on one side to simplify wiring and improve assembly.

  The third unit H3 is a cover member attached so as to sandwich the second unit H2 with the first unit H1. Here, a specific assembly process will be described. First, various oil passages and mounting holes are formed in the aluminum block to form the first unit H1. Next, various electronic components are attached to the second side face H102 of the first unit H1, and fixed by caulking. At this time, since the first side surface H101 facing the second side surface H102 is a flat surface, unnecessary stress concentration or the like is avoided and stable crimping is achieved.

  Next, the motor 50 and the stroke simulator SS are attached. Next, the second unit H2 is attached so as to cover the various electronic components, and the substrate K1 is electrically joined to the various electronic components. Here, the electrical joining represents welding the terminal protruding from various electronic components and the substrate K1 with solder or the like, but it is not always necessary to weld, and electrical connection may be achieved by fitting or the like. . At this time, when welding is performed, the welding can be easily performed by performing the welding on the surface on the third unit H3 side which is the back surface of the second unit H2. Next, the assembly of the brake unit H / U is completed by attaching the third unit H3. By providing the third unit H3 as a cover member in this way, the ease of assembly is improved.

  The upper surface H103 is provided with a plurality of ports H11, H12, H13, H14, H15, and H16 to which various pipes are connected. Oil passages 31 and 32 that are pipes from the master cylinder 3 are connected to the first ports H11 and H12 formed in a substantially central portion of the upper surface H103. Oil passages 33, 33a, 34, 34a, which are pipes from each wheel cylinder W / C, are connected to the second ports H13, H14, H15, H16 formed on both sides of the first ports H11, H12. ing. The third port H17 formed at only one location in the center of the upper surface is connected to an oil passage 36 that is a pipe from the reservoir tank 2. These various pipes are arranged symmetrically about the oil passage 36.

  Next, the perspective view of FIG. 7 will be described. Of the first ports H11 and H12, the port H12 is formed with a lateral hole 32b that communicates with the stroke simulator SS and the shut valve S1 most recently (position close to the upper surface H103). In other words, in this horizontal hole 32b, the stroke simulator SS is arranged on the projection surface onto the first side face H101 of the shut valve S1. Further, a branch oil passage 32a connected to the port H12 is provided in the horizontal hole 32a at the same height position so as to reduce the oil passage resistance as much as possible.

  Hydraulic pressure sensors 21 and 22a are provided in the vicinity of the first ports H11 and H12. The pump discharge hole is provided with two places: a route from the lower part of the pump housing to the check valves 17 and 18 and a route to the third port H17 through the relief valve 19 at the upper part of the pump housing. The check valves 17 and 18 are provided with in-valves 13, 13a, 14, and 14a through vertical holes, and communicated with the vertical holes that reach the second ports H13, H14, H15, and H16. The vertical holes leading to the second ports H13, H14, H15, and H16 are provided at two places on the left and right, and hydraulic pressure sensors 23, 23a, 24, and 24a and out valves 15, 15a, 16, and 16a are provided on the middle branch path. Yes. Further, the outlets of the out valves 15, 15 a, 16, and 16 a of each wheel communicate with each other through a horizontal hole and intersect with an oil passage 36 connected to the reservoir tank 2.

The effect based on the said Example 1 is demonstrated.
(a) The brake unit H / U includes first ports H11, H12 connected to the master cylinder 3 via piping, and second ports H13, H14, H15, H16 connected to the wheel cylinder W / C via piping. Shutoff valves 11 and 12 (corresponding to the first switching valve) for switching between conduction and cutoff of the first ports H11 and H12 and the second ports H13, H14, H15 and H16, and a pump 10 (for the second hydraulic pressure source) Equivalent), a stroke simulator SS (corresponding to a fluid absorber) that stores brake fluid in the master cylinder that is moved by the driver's brake pedal operation, and a branch oil that connects the first port H11, H12 and the stroke simulator SS. The passage 32a and the shut valve S1 (corresponding to the second switching valve) for switching between conduction and interruption of the branch oil passage 32a are provided.

  In other words, the configuration around the master cylinder can be made compact by arranging the stroke simulator SS on the brake unit H / U side, which is an essential component in a brake-by-wire system that ensures braking force via a manual brake circuit during a failure. And the degree of freedom in layout in the engine room can be improved. In addition, the existing master cylinder can be used as it is, and the cost of the system can be reduced.

(b) The second hydraulic pressure source is the gear pump 10 driven by the motor 50, and the motor 50 and the stroke simulator SS are attached to the first side face H101 of the brake unit H / U.
That is, by installing a motor-driven gear pump in the brake-by-wire system, the accumulator as described in the related art can be eliminated. Basically, accumulators must always be filled with high pressure, so they have been enlarged to meet demands for strength and safety. By arranging the stroke simulator SS in a space excluding this accumulator, the space around the master cylinder can be secured without expanding the area occupied by the existing brake unit H / U.

  (c) The brake unit H / U has a substrate K1 electrically connected to the motor 50, the shut-off valves 11, 12 and the shut valve S1, and the shut-off valves 11, 12, the shut valve S1 and the substrate K1 are The second side surface H102 is opposed to the first side surface H101.

  That is, it is possible to ensure ease of assembly such as soldering by arranging the board K1 to be electrically connected and the respective electronic components concentrated on one side surface. In addition, since it is arranged close to the substrate K1, it is possible to easily handle the wiring and to reduce the loss in the wiring as much as possible. In addition, if the surface on which the solenoid valve, the hydraulic pressure sensor, or the like is attached is the same as the surface on which the stroke simulator SS, the motor 50, or the like that is fixed by a screw or the like is attached, the motor or the stroke simulator SS is attached first. The press-fitting or caulking process becomes difficult. Therefore, after the press-fitting or caulking process, the motor and the stroke simulator SS are fixed by screwing or the like. However, when a slight deformation occurs in the surface due to press-fitting or caulking, the screw hole may be deformed and the manufacturing efficiency may be reduced. On the other hand, since it attached to a different surface, the improvement in manufacturing efficiency can also be aimed at.

  (d) The shut valve S1 is attached at a position where the stroke simulator SS attached to the first side face H101 is projected onto the second side face H102.

  In other words, the viscosity of the brake fluid decreases at low temperatures, and if the oil path length between the shut valve S1 and the stroke simulator SS is long, the response from the solenoid valve operation to the piston movement of the stroke simulator is delayed. The delay may give a sense of incongruity to the feeling of depressing the driver of the by-wire control. On the other hand, with the above configuration, the shut valve S1 and the stroke simulator SS can be disposed close to each other, and a hydraulic pressure loss due to the oil passage can be avoided. In addition, it is possible to suppress a sense of discomfort associated with the stroke of the driver's brake pedal.

(e) The branch oil passage 32a and the stroke simulator SS are arranged on the first ports H11 and H12 side with respect to the rotating shaft of the motor 50.
Therefore, it becomes possible to supply the brake fluid on the master cylinder side introduced into the brake unit H / U to the stroke simulator SS through the shortest oil passage, and the hydraulic loss due to the oil passage is reduced as in the effect (d) above. It can be avoided.

(f) The stroke simulator SS is arranged at a position above the motor 50 when the brake unit H / U is mounted on the vehicle.
Since the motor is basically the heaviest component, placing the motor at the bottom and lowering the center of gravity of the entire unit to the bottom can improve the mountability while stabilizing the on-vehicle balance. it can. Further, when a plurality of ports to which pipes are connected are provided in the upper part, the pipe resistance can be reduced by arranging the ports and the stroke simulator SS close to each other.

  Next, Example 2 will be described. Since the basic configuration is the same as that of the first embodiment, only different points will be described. FIG. 9 is a partial cross-sectional view showing the brake unit H / U of the second embodiment. In the first embodiment, a plurality of springs and rubber as an elastic body are arranged in the stroke simulator SS, thereby reproducing the pedaling force characteristics with respect to the driver's brake pedal operation. In contrast, the second embodiment is different in that the pedaling force characteristic is reproduced by electronically controlling the valve opening amount of the shut valve S1.

  The shut valve control unit CU22 of the second embodiment calculates an optimum value as a pedaling force characteristic based on various sensor values, and outputs the valve opening amount of the shut valve S1 corresponding to this value as a command signal. As a result, by adjusting the load by the orifice effect of the shut valve S1, the pedaling force characteristic is set to a desired value. At this time, since it is not necessary to arrange a plurality of springs, rubbers, etc. as shown in the first embodiment, as shown in the partial cross-sectional view of FIG. By doing so, it is possible to reduce the size of the stroke simulator SS.

  It should be noted that the driver's pedaling force characteristic can be set as appropriate according to the traveling state and the like. For example, when the stroke simulator is set near the master cylinder, etc., and at a different location from the brake unit H / U, to perform coordinated control, wiring for communication or a dedicated controller for the stroke simulator can be used. It is necessary to arrange on the communication line.

  At this time, the CAN communication speed is not preferable because the control cycle may not be shortened due to an increase in the bus load, and the controllability is poor and the feeling may be deteriorated. On the other hand, in the second embodiment, the shut valve S1 is also arranged at the same position as the solenoid valve that controls the wheel cylinder pressure of each wheel. Therefore, when cooperative control with brake-by-wire control is performed, the wiring is routed. Etc. and there is no need to increase the number of controllers, so that a stable feeling can be obtained. Further, when a failure occurs in the brake-by-wire system, the shut valve S1 is similarly closed, so that normal manual braking can be executed.

DESCRIPTION OF SYMBOLS 1 Brake pedal 2 Reservoir tank 3 Master cylinder 10 Gear pump 11, 12 Shut off valve 13, 13a, 14, 14a In-valve 15, 15a, 16, 16a Out valve 17, 18 Check valve 19 Relief valve 23, 23a, 24, 24a Fluid Pressure sensor (pipe for wheel cylinder)
31, 32 Oil passage (Master cylinder piping)
32a Branch oil passage 33, 33a, 34, 34a Oil passage (foil cylinder piping)
36 Oil passage (piping for reservoir tank)
50 motor
H / U brake unit
S1 Shut valve
SS stroke simulator

Claims (3)

A brake unit provided on a pipe connecting a master cylinder as a first hydraulic pressure source that generates hydraulic pressure by a driver's brake pedal operation and a wheel cylinder that generates braking force on each wheel,
The brake unit has a first port connected to the master cylinder formed on the upper surface of the housing via a pipe;
A second port connected to the wheel cylinder formed on the upper surface of the housing via a pipe;
A pump provided in the housing;
A motor attached to the first side surface of the housing for driving the pump;
A stroke simulator for storing brake fluid in a master cylinder that moves by operating the driver's brake pedal;
With
The stroke simulator, between the upper surface and the first imaginary line parallel to the street the upper surface of the motor rotation shaft of the motor in the first aspect, the third side surface formed continuously to said first side surface When viewed, the stroke simulator and a part of the motor overlap, deviate to one side of the second imaginary line passing through the motor rotation axis and orthogonal to the first imaginary line, and viewed from the upper surface side Sometimes, the brake unit is mounted at a position where the stroke simulator and a part of the motor overlap . The brake unit according to claim 1, wherein
Said stroke simulator, a unit provided on the second side surface opposite to the first side surface of said housing,
With
The stroke simulator is a front Symbol first side surface, mounting the housing when viewed from the first side surface, a position obtained by partially 倚 on the third side face side which is formed continuously to the first side surface And
The unit, when viewed the housing from a first side face, opposite the third side, a fourth side surface which is formed continuously to the first aspect, taking the signal from outside of said housing A brake unit comprising a connection port for connecting with a connector. The brake unit according to claim 1 or 2,
The stroke simulator has a plurality of fixing portions to which bolts for fixing to the housing are mounted on an outer periphery, and at least one fixing portion is disposed at a corner portion of the housing .

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