JPS6127321Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a hydraulic pressure control device used in a two-system control system in which brake fluid pressure generated in a master cylinder etc. is transmitted to the left and right rear wheels of a vehicle through two independent piping systems. It is related to.

The present applicant previously developed a two-system control system in which the valve pistons of a pair of proportioning valves were installed in parallel in one housing as a device for controlling the brake fluid pressure transmitted to the left and right rear wheels, and both valve pistons were installed in parallel in a single housing. We have developed a system with a common biasing mechanism and applied for utility model registration. Utility Model Application No. 51-130997 (Utility Model Application No. 56-46453) is one such example, in which the biasing mechanism of a pair of proportioning valves can come into contact with the rear ends of both valve pistons of the proportioning valves. a transmission member having a shape, a holding member that holds the transmission member so as to be movable in the axial direction, and a holding member disposed between the holding member and the transmission member to connect both the valve pistons via the transmission member. a spring that urges the holding member to the non-operating position; a support member that swingably supports the center portion of the holding member in a plane that includes at least the axes of both valve pistons; provided facing the holding member across a gap,
The holding member is characterized in that it includes a stopper that restricts the limit of the swinging movement of the holding member.

In this hydraulic control device, the elastic force of one spring is distributed equally to a pair of valve pistons by the transmission member, and the discrepancy in the working stroke of the pair of valve pistons caused by manufacturing errors is absorbed by the small angle oscillation of the transmission member and the retaining member. Moreover, if one of the two independent piping systems is damaged, the transmission member moves linearly on the retaining member, which is prevented from oscillating beyond a certain limit by the stopper, and the valve piston receiving the hydraulic pressure from the normal piping system compresses the coil spring by itself, resulting in a remarkable effect in which the hydraulic control start pressure of the normal proportioning valve is increased to about twice that when both systems are normal.

The purpose of the present invention is to provide a hydraulic pressure control device that can obtain the above-mentioned effects and is easy to manufacture. (a) disposed on the outside of the housing on the side where both the valve pistons are exposed, one end of which is connected to the valve pistons by a pivot supported by the housing at an intermediate position between the valve pistons; (b) A cylindrical portion slidably fitted to the guide rod and capable of abutting against the rear ends of both valve pistons. (c) a transmission member installed between the transmission member and the free end of the guide rod, the valve pistons being connected to the rear ends of the two valve pistons via the transmission member; (d) a compression coil spring that applies a biasing force in the direction of pushing the guide rod into the housing, and (d) a small angle centered on a straight line passing through the axis of the pivot and parallel to the axes of both valve pistons. The point is that it is configured to include a stopper device that limits the range.

In this way, the guide rod can be simply attached to the housing or a member fixed thereto by a pivot shaft, and the transmission member can be slidably fitted to the outside of the bar-shaped guide rod, making manufacturing easy. This makes it possible to reduce manufacturing costs.

In addition, since it is easy to reduce the fitting gap between the pivot shaft and the guide rod and the fitting gap between the guide rod and the transmission member, even when vibration is applied to the hydraulic device, the biasing mechanism remains stable. Another advantage of the present invention is that it can prevent rattling and the components of the biasing mechanism from shifting or coming apart from each other.

Hereinafter, one embodiment of the present invention will be described in more detail based on the drawings.

In FIG. 1, 1 is a master cylinder, and a first pressurizing chamber 4 is
Liquid pressure is generated equally in L and the second pressurizing chamber 4R.

The first pressurizing chamber 4L is connected to the inlet port 34L of the hydraulic pressure control device 20 by a pipe 6L, and further includes:
It is connected to the wheel cylinder 12L on the left side of the front wheel through a pipe 8L, while the wheel cylinder 14R on the right side of the rear wheel is connected to the wheel cylinder 12L on the left side of the front wheel.
It is connected to the pipe line 10L.

The hydraulic pressure control device 20 has a housing 23 consisting of a housing body 24 and a pair of cylindrical members 26L and 26R, and a pair of proportioning valve parts 22L and 22R arranged side by side. A cylindrical member 26L is screwed into the opening of a dead-end hole provided in the housing body 24, and a valve piston 28L is inserted into the hollow portion of the cylindrical member 26L. A sealing member 44L is fitted into the upper part of the cylindrical member 26L, and further covers the sealing member 44L.
A seal cover 46L is fixed. A valve element 30L is formed at one end of the piston 28L, and a valve seat 32L is provided in the hole adjacent to the valve element 30L. Further, the other end (unend) of the piston 28 is brought into contact with a transmission member 64 of a biasing mechanism 50, which will be described later.

The pipe line 6L is provided in the housing body 24.
The inlet port 34L is connected to an inlet chamber 36L and an outlet chamber 3 formed on both sides of the valve seat 32L.
8L and communicates with the rear wheel outlet port 40L. Further, the inlet port 34L is also communicated with the front wheel outlet port 42L via only the inlet chamber 36L. Here, the three ports 34L, 42L and 40L formed in the housing body 24 are
Since they are arranged almost radially around the inlet chamber 36L, it is easy to pipe the pipes connected thereto, and the housing main body 24 also serves as a T-shaped joint for branching the pipes. There is.

In addition, the second pressurizing chamber 4R is also connected to the wheel cylinders 12R and 14L of the front right wheel and the rear left wheel in exactly the same manner. The reference numerals L are replaced with R to represent the same parts, and the explanation will be omitted.

Next, the biasing mechanism 50 will be explained.

At the center bottom of the housing body 24, a pair of plate-shaped pieces 51 are formed parallel to each other and directed downward, as shown in FIG. 2, located between the valve pistons 28L and 28R. A head 53 of a round guide rod 52 is attached to the pivot 5 on this plate-like piece 51.
4, the valve pistons 28L and 28R are rotatably mounted in a direction parallel to a plane containing the axes of the valve pistons 28L and 28R. The head 53 of the guide rod 52 has a width that allows it to fit between the pair of plate pieces 51, and from this head 53, a pair of arm portions 56L, 56R extend at right angles to the guide rod 52, as shown in FIG. It is installed protruding in the direction. The arm portions 56L, 56R have grooves with a rectangular cross section, and extend along the bottom surface 57 of the housing body 24 so that the grooves face downward, with the tip portions facing the bottom surface 57 with a precise gap a between them.
is facing. A pair of holes 58L, 58R are formed in the arm portions 56L, 56R concentrically with the axes of the pair of valve pistons 28L, 28R, which are arranged parallel to each other.
The end portions of the valve pistons 28L, 28R pass through the holes 58L, 58R to the arm portions 56L, 56R.
It is slightly protruded from below. In this embodiment, the arm portions 56L, 56R and the guide rod 52 are formed as a pair, but they may be formed as separate bodies.

The guide rod 52 is provided with a transmission member 64 consisting of a cylindrical portion 60 and an operating portion 62 screwed into one end of the cylindrical portion 60.
is fitted to be slidable in the axial direction of the guide rod 52. The action part 62 is the housing main body 2
Although it is a plate-shaped member parallel to the bottom surface 57 of 4, it is provided with upwardly rising protrusions 65L and 65R at both ends. These protrusions 65L, 65R are the arm portion 56
It fits into the grooves of the valve pistons 28L and 28R to prevent the transmission member 64 from rotating around the guide rod 52, and also provides compression at the ends of the valve pistons 28L and 28R that slightly protrude below the arm portions 56L and 56R. They are brought into contact by the biasing force of a coil spring 70. This compression coil spring 70 is arranged between the acting portion 62 of the transmission member 64 and a ring 66 screwed onto the distal end of the guide rod 52.
It is installed with a predetermined preload.

As described in detail above, the guide rod 52 is rotatably attached to the housing body 24 by the pivot 54, and the transmission member 64 is slidably fitted to the guide rod 52. Alternatively, a rotational movement may be performed about the pivot 54. This rotational movement is caused by the arm portions 56 facing each other with a precise gap a in between, as described above.
A stopper mechanism 72 consisting of L, 56R and the bottom surface 57 of the housing body 24 limits the angle range to a minute angle centered on a straight line C passing through the axis of the pivot 54 and parallel to the axes of the valve pistons 28L, 28R. has been done. Note that when the transmission member 64 performs a rotational movement, its operating portion 62 is connected to the valve piston 2.
Although it is unavoidable that the valve pistons 8L and 28R move slightly in a direction perpendicular to their axes, in order to minimize this amount of movement, the pivot shaft 54 is connected to the valve piston 2.
It is desirable to provide it as close as possible to the straight line connecting the ends of 8L and 28R.

The biasing mechanism 50 configured as described above is completely covered by a cover 74 fixed to the housing body 24 with bolts.

The operation of the hydraulic control device 20 in the two-system control device configured as described above is performed when both piping systems are normal (hereinafter referred to as normal) and when damage occurs to either piping system. (hereinafter referred to as "when one system is damaged") will be explained separately.

First, under normal conditions, when the brake pedal 3 is depressed, the first pressurizing chamber 4 of the master cylinder 1
Equal braking fluid pressure is generated in L and the second pressurizing chamber 4R. The brake fluid pressure generated in the first pressurizing chamber 4L is transmitted to the inlet port 34L through the conduit 6L. From there, one side passes through the front wheel outlet port 42L and the conduit 8L to the front wheel left wheel cylinder 12L.
The other one is transmitted to the wheel cylinder 14R on the right side of the rear wheel through the left side valve portion 22L, the rear wheel outlet port 40L, and the conduit 10L. The brake fluid pressure in the second pressurizing chamber is similarly transmitted to the front and rear wheel wheel cylinders.

When the brake pedal 3 is strongly depressed and the brake fluid pressure in the pressurizing chambers 4L, 4R exceeds a predetermined value, the pair of valve parts 22L, 22R start operating. In other words, while large brake fluid pressure is directly transmitted to the front wheel wheel cylinder,
The brake fluid pressure reduced by the valve portions 22L and 22R is transmitted to the rear wheels.

When the hydraulic pressure in the outlet chambers 38L, 38R of the pair of valve parts 22L, 22R exceeds a preset value, both valve pistons 28L, 28R resist the biasing force of the compression coil spring 70, and the transmission member 64 and move it linearly on the guide rod 52, so that the valve elements 30L and 30R are aligned with the valve seats 32L and 30R.
Take a seat in 32R. After seating, both valve pistons 28L and 28R move slightly so that the force applied to the valve pistons 28L and 28R by the brake fluid pressure and the biasing force of the spring 70 are balanced, and the well-known hydraulic pressure control is performed. will be carried out.

Here, the operating strokes (travel amounts) of both valve pistons 28L and 28R should be the same, but
Due to manufacturing errors, etc., there may be a difference in the operating strokes of the two. In this case, the transmission member 64 swings slightly together with the guide rod 52 to absorb the difference.

For example, in the figure, the valve 30L on the left is the valve seat 32L.
If the right valve 30R is completely seated on the valve seat 32R, the fluid pressure in the outlet chamber 38R will be slightly higher than that in the outlet chamber 38L, so both valves Piston 28L,
The transmission member 64, which abuts the end of the valve 28R, swings slightly clockwise (in FIG. 1) around the pivot shaft 54 together with the guide rod 52, and the valve elements of both valve pistons are both seated on the valve seats. .

When both piping systems are normal as described above, even if the guide rod 52 swings, the arm portions 56L and 56R forming the stopper mechanism 72 will not come into contact with the bottom surface 57 of the housing body 24. The gap a between the two valve pistons 28L,
It is set to a value that allows a stroke difference of 28R.

Next, the operation when one system is damaged will be explained.

For example, in the figure, if an oil leak occurs in the conduit 6L, brake fluid pressure is not transmitted to the inlet port 34L. Naturally, the signal is not transmitted to the valve portion 22L and the wheel cylinders 12L and 14R. On the other hand, the brake fluid pressure is transmitted to the other inlet port 34R, and is transmitted to the wheel cylinders 12R and 14L, respectively.

Therefore, when the liquid pressure in the outlet chamber 38R exceeds a certain value determined when both piping systems are normal,
The valve piston 28R begins to move in the direction in which its valve element 30R is seated on the valve seat 32R. At this time,
One protrusion 65R by the valve piston 28R
The transmission member 64 that is pressed is the other protrusion 65L.
is gradually swung clockwise while in contact with the end of the valve piston 28L, compressing the compression coil spring 70. As the transmission member 64 continues to swing further, the left end of the arm portion 56L comes into contact with the bottom surface 57 of the housing body 24, which causes the stopper mechanism 72 to act and prevent the transmission member 64 from tilting any further. At this stage, the valve piston 28R is not seated on the final valve seat 32R.

When the fluid pressure in the outlet chamber 38R further increases, the valve piston 28R presses the transmission member 64 more strongly,
The guide rod 52, which is prevented from swinging by the stopper mechanism 72, is slid downward. At this time, the protrusion 65L of the transmission member 64 is connected to the valve piston 28L.
away from the end of.

At this stage, the valve element 30R of the valve piston 28R is seated on the valve seat 32R.

In this way, when one system is damaged, the valve piston 28R is made to stand alone against the biasing force of the spring 70, so unless twice the normal hydraulic pressure is applied to the piston 28R, the stopper mechanism 72 will prevent the valve piston 28R from swinging. The transmission member 64 cannot be moved downward. In other words, the proportioning valve section 22R starts the hydraulic pressure control operation only when the hydraulic pressure in the outlet chamber 38R becomes approximately twice the normal level.
This means that much higher braking fluid pressure is transmitted than under normal conditions.

The present invention is not limited to the above embodiments, but
It can be implemented with appropriate changes and improvements based on the knowledge of those skilled in the art.

For example, as the stopper mechanism 72, the arm portion 5
It is also possible to form protrusions projecting toward the housing at the ends of 6L and 56R, and to provide a protrusion on the housing body 24 opposite thereto, so that these protrusions are in contact with each other. In this case, a bolt leg part screwed onto the arm part and erected can also be used as the protruding part of the arm part.

Further, when attaching the guide rod to the housing, the attachment portion may be formed integrally with the housing, or a bracket may be fixed to the housing and the guide rod may be attached to the bracket.

Furthermore, the guide rod is not limited to a round bar, but may be square bar-shaped, and the cylindrical portion of the transmission member may have a corresponding shape, or a continuous protrusion or groove may be provided in the axial direction on the guide rod. If opposing grooves or protrusions are also formed on the transmission member and the two are engaged, relative rotation between the two can be restricted and grooves on the arm portions 56L and 56R can be omitted.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of a hydraulic pressure control device according to an embodiment of the present invention, and FIG. 2 is a side sectional view of the main parts thereof. 1: Master cylinder, 22L, 22R: Proportioning valve section, 23: Housing, 28
L, 28R: Valve piston, 50: Biasing mechanism,
52: Guide rod, 54: Axis, 56L, 56
R: Arm part, 60: Cylindrical part, 62: Action part, 6
4: Transmission member, 66: Ring, 70: Compression coil spring, 72: Stopper mechanism.

Claims (1)

[Claims for Utility Model Registration] Valve pistons of a pair of proportioning valves that control the brake fluid pressure transmitted to the wheel cylinders of the left and right rear wheels through two independent piping systems are parallel to each other in a single housing. The hydraulic pressure control device is of a type in which each rear end portion is exposed to the outside of the housing, and the biasing mechanism for both valve pistons is configured such that: (a) both valve pistons of the housing are exposed; one end is placed on the outside of the
a guide rod supported by a pivot supported by the housing at an intermediate position between the two valve pistons so as to be swingable in a direction parallel to a plane containing the axes of the two valve pistons; (c) a transmission member having a cylindrical portion movably fitted therein and an action portion capable of abutting against the rear ends of both the valve pistons; (c) between the transmission member and the free end of the guide rod; (d) a compression coil spring that is attached to the transmission member and applies a biasing force to the rear ends of the valve pistons in a direction to push the valve pistons into the housing; A hydraulic pressure control device for a two-system control device, characterized in that it includes a stopper mechanism that limits the angle range to a minute range centered on a straight line that passes through the axis and is parallel to the axes of both valve pistons.