JP2012162263A - Brake liquid pressure control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability in a brake liquid pressure control device.SOLUTION: An outlet valve arranged between a reservoir and a wheel cylinder for generating braking force in respective wheels by liquid pressure supplied from pumps 10 and 11 driven by motors 12 and 13, is constituted by arranging first outlet valves 16' and 17' being a normally opening valve and second outlet valves 18' and 19' being a normally closing valve in series, and the first outlet valves 16' and 17' are formed of a proportional control valve.

Description

  The present invention relates to a brake fluid pressure control device.

  A conventional brake fluid pressure control device detects a brake pedal stroke and the like, and obtains a braking force based on a pressure accumulated in an accumulator based on the detected result. (For example, refer to Patent Document 1).

JP 2001-526150 A (page 9, FIG. 15).

  However, in the conventional brake fluid pressure control device, all the four wheels are braked by the accumulated pressure of one accumulator, so that it is necessary to store a lot of brake fluid in the accumulator. Here, there are many diaphragm type and piston type accumulators, but if the inflow and outflow of brake fluid are frequently repeated, fatigue of the diaphragm and piston seal portion is promoted, leading to a decrease in durability of the accumulator.

  The present invention has been made paying attention to the above problem, and an object thereof is to improve durability in a brake fluid pressure control device.

  In order to achieve the above object, according to the present invention, an outlet valve disposed between a wheel cylinder and a reservoir that generates braking force on each wheel by hydraulic pressure supplied from a pump driven by a motor is provided as a normally open valve. The first outlet valve and the second outlet valve, which is a normally closed valve, are arranged in series, and the first outlet valve is a proportional control valve.

  Therefore, the accumulator can be eliminated and the durability can be improved.

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

  First, in describing the brake fluid pressure control device of the present embodiment, the configuration of the pump unit will be described. In addition, what is mounted in an engine room like a pump unit is normally attached from the upper side or the lower side of a vehicle. At that time, in order to facilitate the installation of the pump unit, it is desirable to make the connecting operation between the pump unit and the piping as easy as possible and to make the projected area in the vehicle vertical direction as small as possible. Therefore, in order to facilitate the connection work between the pump unit and the piping, the installation method is adopted in which the mounting position of the ports of the gear pumps 10 and 11 is located above the motor shaft and the projected area in the vehicle vertical direction is minimized. .

  FIG. 1 is a perspective view of the brake fluid pressure control unit according to the first embodiment when viewed from the pump motor side. The brake fluid pressure control unit is composed of pump motors 12 and 13, a housing H, and a control unit C / U, which are arranged so as to be layered. Furthermore, the pump motors 12 and 13 are arranged so as to overlap with the housing H in the vertical direction.

  FIG. 2 is a perspective view of the brake fluid pressure control unit according to the first embodiment when viewed from the control unit C / U side. The control unit C / U has been removed for explanation. The brake hydraulic pressure control unit has a plurality of control valves for increasing and decreasing the hydraulic pressure of the wheel cylinder. Here, the shutoff valves 6 'and 7', the inlet valves (proportional valves) 14 'and 15', the first outlet valves (proportional valves) 16 'and 17', the second outlet valves 18 'and 19', the relief valve 21 Each control valve of the “, check valve 22” is housed in a mounting hole (6, 7, 14, 15, 16, 17, 18, 19, 21, 22) formed in the housing H, and the gear pumps 10, 11 These are arranged at a position offset in the horizontal direction with respect to the drive shaft as viewed from the drive shaft side.

  The brake fluid pressure control unit constitutes a hydraulic circuit as shown in FIG. 5 by an attached control valve.

  An outline of the operation will be described with reference to FIG. This circuit is a brake-by-wire control circuit that obtains braking force by driving the gear pumps 10 and 11, which are hydraulic pressure sources, to pressurize the inside of the wheel cylinder in accordance with the driver's brake operation.

  First, when the ignition is turned on by an operation of the driver, the shutoff valves 6 ′ and 7 ′ are energized and shut off. As a result, the communication between the master cylinder M / C and the wheel cylinder W / C is disconnected. When the driver depresses the brake pedal in this state, a drive signal is issued from the control unit to the pump motors 12 and 13 so as to generate a hydraulic pressure corresponding to the pedal stroke. In response to this signal, the pump motors 12 and 13 are rotated, the gear pumps 10 and 11 are driven, hydraulic pressure is supplied to the wheel cylinder W / C, and a pressure increase control is performed to obtain a braking force.

  During this pressure increase, at least one of the first outlet valves 16 ′ and 17 ′ or the second outlet valves 18 ′ and 19 ′ is closed, and the inlet valves 14 ′ and 15 ′ are opened.

  In order to control the hydraulic pressure in the wheel cylinder to be reduced, the hydraulic pressure in the wheel cylinder is returned to the reservoir R by opening the first outlet valves 16 'and 17' and the second outlet valves 18 'and 19'. It has become. In this way, pressure increase and pressure reduction control can be performed. The relief valve 21 ′ is opened when the control circuit becomes higher than the required hydraulic pressure. The check valve 22 'prevents the hydraulic pressure in the wheel cylinder from flowing back to the gear pump side. The hydraulic pressure sensors 23 and 24 are adapted to detect the hydraulic pressure in the wheel cylinder. Also, the left and right hydraulic circuits can be made independent when the isolation valve 20 ′ is closed. As a result, two gear pumps are driven by closing the isolation valve 20 during sudden pressure increase (one gear pump per wheel cylinder), and the gear pump is opened by opening the isolation valve 20 during slow pressure increase. One drive (one gear pump per two wheel cylinders) is also possible.

(Control valve offset arrangement and pump unit vertical projection area reduction)
Here, the case where each control valve is arrange | positioned in the position facing a driven gear on both sides of the drive shaft of the gear pumps 10 and 11 is demonstrated. First, moving each control valve to one side can simplify the oil passage configuration connected to the port. Further, by combining the control valve mounting surface with, for example, the mounting surfaces of the pump motors 12 and 13 of the housing H, the mounting cover (including the control unit C / U) covering the housing H can be combined into one.

  Each control valve is installed in the mounting hole, and is attached to the housing H by caulking the mounting hole edge. When caulking, a large force acts on the housing H, so if the control valve is also installed on the opposing surface, the control provided on the opposing surface when each control valve is installed on the housing H It is necessary to protect the valve, and equipment for that purpose is required. Therefore, the control valves can be easily attached to the housing H by collecting the control valves on one side, caulking and fixing only from one side, and then fixing the pump motor on the other side.

  Further, the control valves are collectively installed on the left side of the gear pumps 10 and 11 in the drawing, and the gear pumps 10 and 11 are arranged eccentrically on the opposite side of the control valve with respect to the pump motor drive shaft. As a result, a certain amount of space can be provided on the left side of the gear pumps 10 and 11, and the strength can be ensured while making the brake fluid pressure control unit compact.

FIG. 3 is an example in which the hydraulic circuit shown in FIG.
In FIG. 3, a configuration is required in which the projected area in the vehicle vertical direction of the present application can be made as small as possible while simplifying the oil passage.

  Therefore, the master cylinder ports 28 and 29 that are input ports and the wheel cylinder ports 34 and 35 that are output ports are collectively arranged on the upper surface where the vertical projected area of the vehicle is small. Thereby, there is an effect that it is difficult for air to accumulate in the pump unit. Further, the control valves are arranged for the left wheel and the right wheel together while being close to the gear pumps 10 and 11.

  Here, since the gear pumps 10 and 11 are superposed in the vertical direction, the left and right control valves are superposed in the vertical direction.

  At this time, arrange the left wheel I / O port close to the left control valve, and arrange the right wheel I / O port away from the right control valve. It is possible to construct a simple oil passage by effectively using the existing location.

(Port mounting position)
Each of the master cylinder ports 28 and 29, the wheel cylinder ports 34 and 35, and the suction suction port S is provided above the motor shaft that drives at least one of the gear pumps 10 and 11. In performing the connection work between the pump unit and the pipe, the worker usually works from the upper side of the vehicle. At this time, by disposing each port so that the motor is disposed below the connection location, it is possible to minimize the influence of the motor unit during connection work.

  FIG. 4 is a diagram illustrating the position of the brake fluid pressure control unit in the engine room according to the first embodiment. (A) is a case where the pump motors 12 and 13 are arranged in a state perpendicular to the vehicle vertical direction. In this case, the projected area (shaded portion) in the vehicle vertical direction becomes large. Therefore, in this embodiment, as shown in (b), the pump motors 12 and 13 are arranged so as to be superposed in the vertical direction when viewed from the vehicle vertical direction. The projected area (shaded area) in the direction can be further reduced.

  Moreover, about the arrangement | positioning of the pump motors 12 and 13, it arrange | positions so that the axial direction of the pump motors 12 and 13 may mutually become the same direction. That is, by aligning the direction of the motor shaft, it is possible to suppress the expansion of the projected area in the vehicle vertical direction by the pump motors 12 and 13 to one direction, and the projected area can be minimized.

  As described above, in the brake hydraulic pressure control device including the hydraulic pressure control means for controlling the wheel cylinder pressure provided in each wheel by the gear pumps 10 and 11 and the control valve of the present embodiment, each port has at least one of the ports. Are provided above the motor shaft for driving the gear pumps 10 and 11. Further, the pump unit in which the control valve is disposed at a position offset in the horizontal direction with respect to the drive shaft when viewed from the drive shaft side of the gear pumps 10 and 11 is fixed to the vehicle.

  As a result, when performing the connection work between the pump unit and the piping, the worker normally arranges each port so that the motor is disposed below the connection part when working from the upper side of the vehicle. The influence of the motor part during connection work can be minimized. Further, it is possible to reduce the projected area in the vehicle vertical direction in the engine room, and it is possible to reduce the size of the pump unit.

  Further, the pump motors 12 and 13 are arranged so as to be superposed in the vertical direction when viewed from the vertical direction of the vehicle. Thereby, the projected area in the vehicle vertical direction can be further reduced.

  Further, the axial directions of the pump motors 12 and 13 are arranged in the same direction. Therefore, by aligning the directions of the motor shafts, it is possible to suppress the expansion of the projected area in the vehicle vertical direction by the pump motors 12 and 13 in one direction, and the projected area can be minimized.

  The brake fluid pressure control device of the present invention may be applied to a brake fluid pressure control device using a pump other than the gear pumps 10 and 11.

It is the perspective view which looked at the brake fluid pressure control unit in Example 1 from the pump motor side. It is a perspective view at the time of seeing the brake fluid pressure control unit of Example 1 from the control unit C / U side. 2 is an example in which an oil passage of the brake fluid pressure control device of Embodiment 1 is formed in a housing H. FIG. It is a figure showing the position of the brake fluid pressure control unit in the engine room in Example 1. 2 is a hydraulic circuit of the brake fluid pressure control unit according to the first embodiment.

S Suction suction port 6 ', 7' Shut-off valve 10, 11 Gear pump 12, 13 Pump motor 14 ', 15' Inlet valve (proportional valve)
16 ', 17' 1st outlet valve (proportional valve)
18 ', 19' Second outlet valve 20 'Isolation valve 21' Relief valve 22 'Check valve 23, 24 Hydraulic sensor 28, 29 Master cylinder port 34, 35 Wheel cylinder port

Claims (2)

A wheel cylinder for generating braking force on each wheel by hydraulic pressure supplied from a pump driven by a motor;
An outlet valve disposed between the wheel cylinder and the reservoir;
Hydraulic pressure control means for outputting a command to reduce and increase the wheel cylinder pressure to the outlet valve;
In a brake control device comprising:
The outlet valve has a first outlet valve that is a normally open valve and a second outlet valve that is a normally closed valve arranged in series,
A brake control device characterized in that the first outlet valve is a proportional control valve. The brake control device according to claim 1, wherein
The pump is provided on each wheel,
The brake control device according to claim 1, wherein the hydraulic pressure control unit executes brake-by-wire pressurization for supplying brake hydraulic pressure to the wheel cylinder by driving the pump in response to a driver's brake operation.

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