JPH0523980B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a brake hydraulic pressure control device that controls the hydraulic pressure of a rear wheel cylinder by appropriately setting the distribution of braking force between the front and rear wheels of a vehicle.

(Prior Art) As this type of brake hydraulic pressure control device, one using a linkage-type load-sensing proportioning valve (load-responsive hydraulic pressure control valve) shown in FIG. 3, for example, is conventionally known. In this device, a change in vehicle weight is detected by converting a dimensional change between the sprung and unsprung parts of the vehicle body into a change in the load on the proportioning spring 46 via the lever member 45. This spring load is then directly transmitted to the plunger 47 of the hydraulic control valve section A to control the opening and closing of the valve body 48. In other words, when the hydraulic pressure at the operation start point (constant hydraulic pressure) is set by the spring load through this detection, the hydraulic pressure from the master cylinder is reduced based on this when the brake pedal (not shown) is depressed. is applied to the rear wheel cylinder on the rear wheel side as an appropriate braking force.

(Problems to be Solved by the Invention) According to this method, the above-mentioned operation start point is set by measuring the load acting on the plunger 47 or adjusted by measuring the set length of the spring 46. However, there is a problem in that adjustment work during inspection and maintenance is complicated and takes a long time.

The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a brake hydraulic pressure control device that can quickly and accurately perform adjustment work associated with setting an operation start point.

(Means for Solving the Problems) To achieve this object, a brake fluid pressure control device according to the present invention includes a valve housing provided on a spring of a vehicle body, and a master cylinder housed within the valve housing. A valve body moves in the direction of closing the flow path when the reduced pressure of a spring member that is energized; a movable member that is locked to the other end of the spring member and is movable in the expansion and contraction direction; and a swinging member that has one end rotatably supported on the spring or the housing; a pressing member that is integrally provided on the swinging member and moves in a direction that engages with the movable member and causes the spring member to expand and contract via the movable member; a link member rotatably connected to one end and rotatably supported at the other end under the spring of the vehicle body so that the length between both ends can be adjusted; a positioning member that is removably attached to the housing and positions and fixes the swinging member at an initial rotational position with respect to the housing.

(Embodiment) Hereinafter, an embodiment of the brake hydraulic pressure control device of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 schematically shows how the brake hydraulic pressure control device of the embodiment is mounted on a vehicle. 1 is a vehicle body, 2 is a bracket, and 3 is a valve housing of a hydraulic pressure control valve section A supported and fixed to the vehicle body 1 via the bracket 2. Specifically, as shown in FIG. 2, the inside of the housing 3 is , the valve body chamber and the pressure regulating spring (spring member) for adjusting the valve pressing force.
The spring chambers in which the springs 4 are fitted are defined such that their axial directions are substantially parallel.

In the valve body chamber, first and second input ports 11, into which hydraulic pressure P _M is introduced from the master cylinder 5,
12 and an output port 13 for hydraulic pressure P _R led out toward the rear wheel cylinder 14, respectively. 15 indicates a front wheel cylinder. Further, reference numeral 16 indicates a plunger that is movable in the vertical direction in the figure, and the valve body 17 is operated by this plunger 16 to open and close the fluid flow path. For example, when the brake pedal 6 is depressed during braking, the hydraulic pressure supplied from the master cylinder 5 is increased.
When P _M reaches or exceeds the operation start point (constant hydraulic pressure), the poppet valve (valve body) 17 moves the plunger 16 in the direction of closing the liquid flow path, reducing the pressure in the rear wheel cylinder 14. It is adapted to supply a controlled hydraulic pressure _PR .

Next, the spring chamber is provided approximately parallel to the valve body chamber, and is approximately parallel to the axial direction of the poppet valve 17 in the spring length direction of the fitted pressure regulating spring 4. A movable piece 20 fixed to the upper end of the pressure regulating spring 4 engages with one and the other of the valve arms 22 of the lever valve together with the plunger 16 on the valve body chamber side, and is movable by the elastic force of the pressure regulating spring 4. Piece 20 remains in a balanced position. The movable piece 20 and the plunger 16 constitute a transmission member. Valve arm 2
2 is a fulcrum 22 that is in contact with the lid 3d of the housing 3;
It can swing freely around a. The position of the swing fulcrum 22a can be set freely, and the ratio of the fulcrum lengths b ₁ and b ₂ (b ₁ :
By setting b ₂ ), the degree of freedom in designing the size and strength of the pressure regulating spring 4 increases in response to changes in the corner force.

Further, in the spring chamber below the pressure regulating spring 4, a pressing piece (movable member) 23 is slidably fitted to engage with the lower end of the pressure regulating spring 4. The piece 23 is energized in a direction that pushes it downward.

On the other hand, in the lower part of the housing 3, a pressing mechanism is provided that pushes up the pressing piece 23 upwardly inside the spring chamber against the urging force of the pressure regulating spring 4. The configuration of this pressing mechanism is such that one end 30a of a swinging arm (swinging member) 30 is rotatably supported by the housing 3;
The upper end of a link member 33 is rotatably connected to the other free end 30b of the link member 33 via a ball joint 32.
The lower end of this link member 33 is connected to, for example, a bungee-yaw type axle housing 34 on the rear wheel side shown in FIG.
It is fixed to via a bracket 35. Further, a push rod (pressing member) 31 is attached to approximately the center of the swinging arm 30 in a manner that projects toward the pressing piece 23 and is sealed in a fluid-tight manner by an elastic boot 36.
The push rod 31 contacts the pressing piece 23 from below via the swinging arm 30 and acts to push it upward against the biasing force of the pressure regulating spring 4.

The link member 33 has an assembled structure of a push-type rod part 33A and a socket part 33B with inner and outer cylinders so that the length l of the upper and lower ends connected to the ball joint 32 and the bracket, respectively, can be adjusted. A pair of clamp parts 33C,
The length l can be set to any value by loosening and tightening according to 33C.

Further, at the stage of the series of assembly steps of the structure, the swing arm 30 is positioned and fixed at a position rotated by a predetermined angle around one end 30a of the swing fulcrum with respect to the housing 3. That is, 40 is a U-shaped fixing arm (positioning member) that fixes the swinging arm 30 at a predetermined rotational angle position, and a pair of locking pins 40a, 40a protrude in parallel from both ends of the arm. Molded. Both the housing 3 and the swing arm 30 have locking holes 3a, which correspond to the locking pins 40a, 40a at both ends.
30c is provided, and the swinging arm 30 is fixed to the housing 3 by fitting the locking pins 40a, 40a of the fixing arm 40 into the locking holes 3a, 30c. It is preferable that the fitting strength is such that the fixing arm 40 does not accidentally come off from the housing 3 and the swinging arm 30, and that it is easy to remove the fixing arm 40 during disassembly.

Next, the operation of the embodiment will be explained.

On the production line, when the assembled vehicle is empty loaded, the swing arm 30 is fixed to the housing 3 by the fixing arm 40 as shown in FIG. In this way, the swing arm 30 is positioned and fixed,
After carrying out necessary setups such as transportation in this state, the length l of the link member 33 is adjusted to the clamp portions 33C and 33C so as to correspond to the preset loading weight.
Adjust by operating. After the length k of the link member 33 is adjusted, the fixing arm 40 is removed from both the housing 3 and the swing arm 30. When the swing arm 30 is released from the housing 3, the weight of the vehicle causes the push rod 31 to move upward via the link member 33 and the swing arm 30 in order, pushing up the pressing piece 23 from below. to compress the pressure regulating spring 4. That is, the set length of the pressure regulating spring 4 is initially set in this way, and the setting of the starting point of operation is performed by the load conversion by the pressure regulating spring 4.

The set length of the pressure regulating spring 4 changes depending on the weight of the vehicle on the market, and when a braking operation is performed by depressing the brake pedal 6 while driving, the hydraulic pressure in the master cylinder 5 changes. _PM increases. When the hydraulic pressure P _M from the master cylinder cylinder 5 further increases and exceeds the hydraulic pressure for starting operation (the set spring load of the pressure regulating spring 4) and is introduced from the input port 11 of the valve body chamber, this introduction The plunger 16 is pushed upward in the figure by the hydraulic pressure. The valve arm 22 is pushed up by this upward movement of the plunger 16, and rotates clockwise around its swing fulcrum 22a, causing the movable piece 20 in contact with the other end to move downward in the figure. Push down.

Depending on the degree of rise of the plunger 16, the valve body 17 moves in the direction of opening the flow path, reduces the rising hydraulic pressure P _M from the master cylinder 5, and transfers this controlled hydraulic pressure to the rear wheel cylinder. 14 is derived from the output port 13 and supplied as an appropriate hydraulic pressure _PR .

(Effects of the Invention) As can be understood from the above, according to the brake fluid pressure control device of the present invention, for example, the spring member (proportioning spring) when the vehicle is unloaded or has a light load is Then, the adjustment to set this to the initial length is performed by a simple operation of fixing the swinging member with the positioning member and adjusting the length of the link member after removing the positioning member, and adjusting the setting of the operation starting point. It can be done quickly and accurately.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the assembly of an embodiment of the brake fluid pressure control device according to the present invention mounted on a vehicle, FIG. 2 is a sectional view of the brake fluid pressure control device, and FIG. 3 is a schematic diagram of a conventional device. FIG. 3... Valve housing, 3a... Locking hole, 4
...Pressure adjustment spring (spring member), 5...Master cylinder, 14...Rear wheel cylinder, 15
...Front wheel cylinder, 16 ... Plunger, 17 ... Poppet valve (valve body), 22 ... Valve arm, 23 ... Pressing piece (movable member), 30 ...
Swing arm, 30c... Locking hole, 31... Push rod (pressing member), 33... Link member, 3
3A...Rod part, 33B...Socket part, 33
C... Clamp part, 40... Fixing arm (positioning member), 40a... Stopping pin.

Claims (1)

[Claims] 1. A valve housing provided on a spring of the vehicle body, a valve body that is housed inside the valve housing and moves in a direction to close the flow path when the hydraulic pressure of the master cylinder exceeds a predetermined value, and the inside of the valve housing. a spring member that biases the valve body in the direction of opening the flow path via a transmission member that is housed in the spring member and is locked at one end; a movable member; a swinging member having one end rotatably supported on the spring or the housing; and a swinging member integrally provided on the swinging member and engaging with the movable member to move the movable member. a pressing member that moves in the direction of expanding and contracting the spring member via the swing member; A link member whose length can be adjusted, and both end portions of the link member are removably attached to the housing and the swinging member to position and fix the swinging member at an initial rotational position with respect to the housing. A braking hydraulic pressure control device comprising: a positioning member;