JPS6198661A - Reducing valve having bypath - Google Patents

Abstract

PURPOSE:To simplify the parts and to improve the reliability by providing a reducing valve for one system on a piston receiving the pressures in two systems in facing direction while stopping the function of reducing valve through motion of piston upon fault of other system. CONSTITUTION:Under normal operation of two systems, the cross-section of piston 5 is such as A=B>C thereby the piston 5 will stop at the left position because of the differential pressure receiving area. Consequently, the reduction valve 9 will execute normal pressure reducing function. Upon fault of second system at the inlet 2'. The piston 5 will move to the right because of the pressure difference. Here, an O-ring 15 of piston 5 will also move to the right to be deviated from the seal section of the bore 4 area B. Consequently, a bypath directly communicating between the inlet 2 and outlet 3 is formed to eliminate pressure reducing effect of reducing valve 9.

Description

[Detailed description of the invention] Industrial application field In order to approximate the power distribution to an ideal state, the pressure of at least one system is reduced when two systems are normal; The present invention relates to a pressure reducing valve with a bypass function that stops the pressure reducing action of.

Problems and Means to be Solved by the Invention From a safety perspective, it is common to divide the braking circuit of a vehicle into two systems.
Various types of piping are used, including the X piping that divides the rear wheel into sash-like shapes. In either case, a pressure reducing valve is used to reduce the rear wheel brake pressure compared to the front wheel in order to approximate the ideal braking force distribution between the front and rear wheels.
If one system fails, the M of the pressure reducing valve of the surviving system will be changed to ensure braking force.1. It is also common to stop the If action. On the other hand, 11 [In order to reduce the number of steps required to bleed air from the brake piping system during both assembly processes and to prevent residual air, the brake piping system is evacuated from the master/cylinder reserve tank by +J+ air, and then the brake fluid is removed. It is desirable that no brake fluid remains inside the components of the piping system, since so-called vacuum filling may not be completed. Therefore, in order to guarantee the quality of component parts at the manufacturing stage, conventional master/linders can only be inspected for leaks using low air pressure, but pressure reducing valves are inspected using high brake fluid pressure due to the need to inspect pressure reduction performance. It was common for the brake fluid in the rear interior to be drained (1) and then supplied to the vehicle manufacturer. On the other hand, in recent years, in order to reduce the man-hours for installing the pressure-reducing valve to the vehicle body and the man-hours for piping, it has been carried out to house the pressure-reducing valve inside the master turn cylinder. It is quite difficult to test the pressure reducing valve section with different working fluids. For this reason, the components of the pressure reducing valve are not directly housed in the body that includes part of the master cylinder, but are partially inserted into the sleeve, and then the pressure reduction performance is inspected using brake fluid pressure. The entire casing is put back into the body that makes up the master cylinder, and the entire master cylinder is inspected using low air pressure before being supplied to vehicle manufacturers. In this case as well, it goes without saying that means for stopping the depressurizing action of the surviving pressure reducing valve in the event of failure of one system is necessary as described in the above-mentioned casing, as well as the components of the pressure reducing valve. However, there are problems in that the internal parts become smaller and more complex, and the reliability and assemblability deteriorate accordingly.

Therefore, the present invention aims to solve these problems using extremely simple means. 1! The casing was provided as a convenient means for quality assurance.
This system is applied to a depressurizing action stop mechanism in the event of a system failure, and the internal pressure reducing valve is made into a simple pressure reducing valve, thereby achieving the objective of -1.

The casing is made into a piston that can receive two systems of liquid W in opposite directions and slide in the axial direction,
When the pressures of the two systems are substantially equal and normal, this piston is kept stationary at the neutral position and the pressure reduced by the pressure reducing valve is outputted, and when one system fails, the piston is moved to the failed side. As a result, a bypass path is formed that communicates the inlet and outlet of the survival side, and the pressure reducing action of the pressure reducing valve is stopped.Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The pressure reducing valve of the first embodiment shown in FIG.
In a bore 4 provided to communicate two systems of hydraulic inlets 2 and 2', two members 5 are slidable in the axial direction.
A piston 5 formed by press-fitting the cylinders a and 5b into each other is housed, and within this piston 5 is a hydraulic pressure response biased in the valve opening direction by a spring 6 that determines the hydraulic pressure at which the pressure reduction action starts. A well-known pressure reducing valve 9 is housed in which the small diameter part 7a of the plunger 7 protrudes in a liquid-tight manner, and the large diameter valve head 71) is disengaged from the plunger 8 during pressure reduction. The hydraulic pressure of the first system introduced from 2' is reduced via passage 12.
The hydraulic pressure of the system is directly guided to the front wheel brakes II and II' through the 13' IIY peak.On the other hand, the input pressure of the two systems is separated fluid-tightly by an O-ring 14 provided around the outer circumference of the piston. The input pressure of the second system acts on the area A, biasing the screw i-n 5 toward the first system.In addition, the input pressure of the second system and The output pressure is fluid-tightly divided by an area B around the outer periphery of the piston 5, and an O-ring 1 provided at the left end of the piston 5.
6, the left end of the bus i.n.5 has an area C and is open to the public. Therefore, if A=B>C, only the output pressure on the first system side acting on the area B-C becomes a force that forces the piston 5 toward the second system side, and the second output pressure acting on the area A Since the biasing force exerted on the first system side by the human power 1■: of the system is always large &f, when both systems are normal, the left end 5c of the screw I/N 5 is always attached to the bottom 17a provided on the plug 17. They are in contact and the state shown is maintained.

On the other hand, 1); The second system including the no-wheel brake II and 11' was lost, 1+61L! When +1 pressure is no longer applied to the piston 5, the biasing force acting on the area A toward the first system side disappears, and only the biasing force acting on the area B-C toward the second system side becomes as shown in Fig. 2. The screw 5 moves toward the second system until its right end 5d abuts the bottom 4a of the bore 4.

Then, the O-ring 15 also moves to the second system side along with the screw I5, and the O-ring I5 comes off the seal part of area B provided in the bore 4, and the O-ring I5 is attached to the outer periphery of the O-ring I5. A bypass path is formed that directly connects the inlet 2 and the outlet 13 of the first system, and a pressure equal to the input pressure is outputted to the inlet 13. Furthermore, while the second system is defective, the piston 5 always maintains the position shown even after the pressure in the first system is removed, and after the failure in the second system is repaired. The first pressurization results in (return to +''I position) 6 in Figure 1.

Therefore, as shown in FIG. 2, the terminal 18 of the reciprocating switch of the electric circuit is connected to the piston/
If it is applied to the end face 5c, it is also possible to display an alarm for the loss of V61.

The point where the output pressure generated by the pressure reducing valve 9 during the second system 12' is arranged (therefore, the direction of the pressure reducing valve 9 is opposite to that in the first embodiment), the first There are two O-rings 14a and 14b that separate the system and the second system, and an air chamber that communicates with the outside is provided in the middle, so that failure of the sealing means that separates the two systems can be recognized as a liquid leak. The O-ring at the left end of the piston 5 has been eliminated, the protrusion of the piston into the atmosphere has been increased by I/6 +1, and an offset spring 19 has been installed to always bias the piston 5 toward the first system side. This embodiment differs from the first embodiment shown in FIG. 1 only in this respect.

Therefore, if A and B are set, the input pressures of each system will act oppositely on the same area, so when normal, the offset spring 1
Due to the biasing force 9, the left end of the piston 5 comes into contact with the tip 171 of the plug 17, and the state shown in the figure is maintained. Therefore, the input and output pressures of the second system are liquid-tightly divided by the O-ring 15, and the input pressure of the first system introduced from the inlet 2 is reduced by the pressure reducing valve 9 through the passage 12, and then 3 and is led to the rear brake. In addition, if the second system of the front wheel system fails, only the pressure of the first system acts on the area A, so when the biasing force of the offset spring 19 is lower than the pressure reduction start pressure of the pressure reducing valve 9, the piston 5 moves to the second system. If it is set so that it moves to the side, the inlet 2 and outlet 1 of the first system are connected to the outer circumference of the O-ring I5 at 1111 when the pressure reducing action by the pressure reducing valve 9 is started, as in the case of the first embodiment. 13
A bypass path is formed connecting the input pressure and the output pressure equal to the input pressure is supplied to the rear wheel brakes via the output 13.In addition, in this case, unlike the first embodiment, the second system is lost. When the pressure in the first system is removed, the piston 5 is moved to the position shown in the figure by the force of the spring 19.
It returns to failure and moves to the second system side every time the pressure reaches 91'.

The left end of the piston 5 is opened to the atmosphere in a liquid-tight manner with an area C by an O-ring 16, and A=B>C, as in the first embodiment shown in FIG. When it is normal, keep it in the position shown in the figure 14, turn it on [12',
While the second system side including the outlet [13' is defective, the right MiiJ5d of the piston is kept in contact with the bottom 4a of the bore 4, and the initial pressurization after the defect is repaired causes the piston to move as shown in the figure. The only difference from the second embodiment shown in FIG. 3 is that it is returned to its original position. In addition, piston 5
The communication hole 5e provided at the left end of the piston 5 is connected to the space formed between the popular protruding end 5C of the piston 5 and the bottom part 178 of the plug 17 when the piston 5 moves to the second system side, and the connecting hole 5e of the plunger 7. It communicates with the atmospheric chamber formed at the end of the small-diameter portion 7a protruding from the top.By increasing the volume of this popular chamber, a rise in pressure during assembly is prevented. In particular, it is provided for the purpose of alleviating the pressure drop in the 111J atmospheric chamber during movement of the piston 5 and smoothing the movement of the piston 5.

The fourth embodiment shown in Figure 7F5 has two parts 5a.

Inside the piston 5, which is formed by applying force/mechanism in a liquid-tight manner to the piston 5, there is a small-diameter portion 7a1, which is biased in the valve opening direction by a spring 6, and a large-diameter portion 7a1 whose outer diameter side is rounded at both ends in a liquid-tight manner. 7
Connect both ends of b to the center? The valve portion 7d formed at the end of the small diameter portion of the liquid passage 7c is connected to the planter 7 and the poppet spring 22, which are capable of sliding in the axial direction. A pope positioned at the end of the valve holder 21.

A well-known poppet valve type pressure reducing valve 9 consisting of a valve seat 8 is housed. Further, the valve holder 21 is fixed to the plug 17 which is attached and screwed to the body 1, and the poppet valve seat 8 cannot be moved from the illustrated position to the active position. On the other hand, the outer circumference of the piston 5 is 0 to ring +4a,
14b, the pressure of the first system from inlet 2 and large +12'
The pressure of the second system is separated from each other in a liquid-tight manner, and the human pressure and output pressure of the first system are separated by an 0-U puffer 15. Furthermore, the piston 5 is
The left end of is open to the public in a liquid-tight manner. Therefore, assume that the ring area on the outer diameter side of O-rings +4a, 14b, and 15°IB is all the same and call it A, and the ring area on the outer diameter side of 0-IJ song 0 as B. The piston 5 is held in the position shown in order to bias it in the opposite direction.

At this time, if Q, >Q is set, the input pressure of the second system from the inlet 2 is reduced through the pressure reducing valve 9 through the passage I2, and then
The pressure is supplied to the rear wheel brakes via the passage 13 (exit 13). Also, 1) the input pressure of the second system from the inlet 2' is directly supplied to the 11 wheel brakes via the outlet 3'. When the second system including the front wheel brake fails, the piston 5 moves to the right by a distance Q3 due to the input pressure of the first system acting on the area B, and its right end 5d hits the bottom 4a of the bore 4. At this time, since the poppet valve seat 8 is left in the position shown in the figure as described above, the movement h1 required for the valve portion 7d of the plunger 7 to abut against the poppet valve seat 8 is Q+ + Q3.
, and this is the movable distance of plunger 7 Qt.
If the valve part 7d is left in the position shown in FIG.
The input pressure of the first system becomes a bypass path that directly communicates with the input pressure of the first system. The state of movement toward the defect side is maintained until the pressure is reached.

The fifth embodiment shown in FIG. 6 is an application of the present invention to a pressure reducing valve for X piping. That is, in the part of the body 1 that houses the master turn ring, there is a
In the bore 4 provided to communicate the hydraulic pressure input n2.2' of the system, three members 5a+ are slidable in the axial direction.
A piston 5 formed by press-fitting the pistons 51) and 51)' into each other is housed, and this piston 5
Inside, there are plungers 7 that are biased in the valve opening direction by engaging with both ends of a spring 6 that determines the hydraulic pressure at which the decompression action starts.
．． 7'.

The well-known Lip Knoll type pressure valves 9 and 9' consisting of pumps 8 and 8' are housed symmetrically, and the hydraulic pressure of the first and second systems introduced from the inlet n2.2' is passed through the passage 12°12. ′
After being reduced in pressure by the pressure reducing valves 9, 9' via the outlet 1123.23', the hydraulic pressure is led to the front wheel brakes II, 11' without being reduced in pressure. On the other hand, an O-IJ song 4.14' is provided on the outer periphery of the piston 5 to liquid-tightly partition the boundary between the atmospheric chambers formed for the input doses of the two systems. When the system is in the state shown in the figure, the input pressure and output pressure of each system are separated in a fluid-tight manner. Further, both ends of the piston 5 protrude to the atmosphere in a liquid-tight manner through O-rings IG and 1G'. On the other hand, the O of piston 5
- At the position of the ring 14, the sleeve 24 is slidably inserted into the piston 5 on its inner diameter side and the bore 4 on its outer diameter side, and its right end is provided between the stepped portion 5e of the piston 5 and the bore 4. They are respectively abutted against the shoulder portions 4b. O-ring 14
7-ring on the outer diameter side of A1, B on the inner diameter side, O-ring 1
Let E and E' be the area of the outer diameter side/- by 4', and the respective areas are A>C>B>D=[)'=E=E'/jl+< is set. Therefore, under normal conditions, when the hydraulic pressures of the two systems from the inlets 2 and 2' are substantially equal, the hydraulic pressure of the first system on the left side is also C-
The pressure of the second system on the right acts on the area of D', and C〉
Since B>D=D', the piston 5 is forced to the left, but the first
Since input pressure on the system side acts and A>C, piston 5
is biased to the right, and the right end of the sleeve 24 is held at the neutral position shown in the figure, where it is in contact with the shoulder 4b of the bore 4. On the other hand, the rightward biasing force of the input pressure of the first system that acts on the second system on the right side is 1 (B-1 because the leftward biasing force acting on C-D' disappears when 6i). The right end 5d of the piston 5 moves until it comes into contact with the bottom 4a of the bore 4, and 0-
The outer periphery of the ring 15 escapes from the guide hole +7b of the plug I7, forming a bypass path connecting the inlet 2 and the outlet 3, and the input pressure from the inlet 12 passes through the outlet 3 without being reduced. It is supplied to the wheel brakes 10. At this time, the sleeve 24 is held in the illustrated position, and its right end and the stepped portion 5e of the piston 5 are separated. Even after the first system on the surviving side is depressurized, no force is applied to return the piston 5, so while the second system is in failure, the piston 5 is always in the second system.
The state of movement to the grid side is maintained. The failure was repaired 2
The first actuation, in which the system is supplied with substantially equal input pressures, automatically returns to the neutral position shown because C-D'>B-1). Furthermore, when the first system on the left side fails, the left end 5c of the screw 5c is biased to the left by the input pressure of the second system acting on C-1)'. The O-ring +5' escapes from the guide hole of bore 4, and the second
A bypass path is formed that connects the system side inlet 2' and outlet 3'. At this time, the sleeve 24 is moved leftward with its right end engaged with the stepped portion 5e of the piston 5. or,
As with the failure of the second system, the state of movement toward the first system is maintained until the failure on the first system side is repaired, and since A>C, the first pressurization after the failure is repaired causes the Automatically returns to neutral position.

In this embodiment, the internal pressure reducing valve is not limited to the knob seal type; it goes without saying that other types may be used, including the poppet valve type shown in the fourth embodiment; By fixing the poppet valve seats of the two systems to the body, the principle of the fourth embodiment can be applied to the container to make it a pressure reducing valve for the X pipe.

As described in detail, the pressure reducing valve of the present invention has been provided as a convenience measure for "quality assurance" and has been fixed to the body, but one system has failed. By applying the piston to the depressurization stop mechanism as a piston that can sometimes move to the defective side, the internal pressure reducing valve can be made into a simple pressure reducing valve, reducing the number of parts and reducing the number of sys1 due to the surface element, and improving reliability. This is an epoch-making device that can extremely easily achieve the first objective in terms of workability, and can also easily detect failures in piping and the like.

[Brief explanation of the drawing]

Fig. 1 shows the first embodiment of the present invention, Fig. 2 shows the state of the first embodiment at 1 o'clock, Fig. 3 shows the second embodiment, and Fig. 4 shows the state of the third embodiment. FIG. 5 is a schematic cross-sectional view of the main parts of the fourth embodiment, and FIG. 6 is a fifth embodiment. 1... hoty, 2... people [1, 3... out [1,
4...Bore, 5...Bis)・N, 6...Spring, 7...Plan/Year, 8...Lip knoll (or poppet valve), 9...Pressure reducing valve, lO・...Rear wheel brake, 11...Front wheel brake, 12.13...L (
k passage, +4.15. IG...0-ring, 17...
・Plug, 18... Reciprocating switch terminal, 19...
Offset spring, 20...O-ring, 21.
...Valve holder, 22...Popey l spring,
23...Exit, 24...Sleeve. Dimension diagram

Claims (5)

[Claims] (1) A piston is provided that can slide by receiving two systems of pressure in the axial direction and in directions facing each other, and the pressure of one of the two systems is reduced and output inside this piston. A pressure reduction device with a bypass, characterized in that at least one valve is accommodated, and when one system fails, the piston is moved to the failure side to stop the pressure reducing action of the pressure reducing valve of the surviving system. valve. (2) An annular seal means is provided on the outer periphery of the piston to liquid-tightly partition the input pressure and output pressure of the pressure reducing valve when both systems are normal, and when one system fails, the piston fails. By moving to the side, the sealing means becomes ineffective and a bypass passage connecting the input pressure and the output pressure appears on the outer periphery of the piston. valve. (3) the pressure reducing valve has a movable valve body attached to a hydraulic pressure-responsive plunger that has a small area facing input pressure and a large area facing output pressure, and has a limited relative movement distance with respect to the piston;
The movable valve includes a fixed valve seat that is immovable with respect to the body in which the piston is housed when the pressure is increased, and when the distance between the movable valve body and the fixed valve seat is equal to or less than the relative movement distance of the plunger with respect to the piston during normal operation. The pressure reducing effect of the pressure reducing valve is exerted by moving the body toward and away from the fixed valve seat, and when one system fails, the distance between the movable valve body and the fixed valve seat is reduced by moving the piston toward the failed side. Claim 1, characterized in that the movable valve body is made to be at least a relative movement distance, so that the movable valve body cannot come into contact with the fixed valve seat, thereby stopping the pressure reducing action of the pressure reducing valve. Pressure reducing valve with bypass as described. (4) After the operation is completed when one system fails, the piston is automatically returned to the position during normal operation in which the sealing means is effective. The pressure reducing valve with bypass according to item 2 or 3. (5) After the operation is completed when one system fails, the piston is held at the position after the operation is completed until the failure is repaired, and the piston is automatically returned to the position when it is in normal operation by the first operation after the failure is repaired. Claim 1, characterized in that:
The pressure reducing valve with bypass according to item 2 or 3.