JPS60175899A - Pulsation inhibitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to anti-skid systems for automobiles, for example;
) The present invention relates to a device for suppressing pulsations in the discharge pressure of a pressure source used in a power steering system.

Conventional anti-skid systems for automobiles always maintain appropriate brake pressure by pumping out the oil in the wheel cylinder within a percentage limit in order to prevent the wheels from skidding when extending or applying the brakes. It is something. However, there is a problem in that the oil pumped out during pump operation I:1 returns to the mask cylinder and pushes the brake pedal back, causing a so-called kick-pack phenomenon and worsening the brake feeling.

Additionally, power steering systems attempt to reduce steering forces by using the oil pressure generated by the oil pump, but if there is pressure pulsation in the oil pressure generated by the oil pump, so-called chatter may occur during steering. However, there is a problem that the steering feeling becomes sad.

OBJECTS OF THE INVENTION The present invention aims to reduce kickback appearance, pressure pulsation, and the like.

A pulsation suppressing device according to the present invention connects a discharge part and an inlet part of a pressure source for supplying pressure fluid to an operating part by a communication passage, and provides an on-off valve in this communication part, and the on-off valve The opening is opened according to the operating state of the operating section, and the pressure fluid discharged from the discharge section is returned to the inlet section, thereby suppressing pulsation of the discharge pressure of the pressure fluid.

Example The present invention will be explained below with reference to illustrated embodiments.

FIG. 1 shows an anti-skid system. Mask cylinder 1? It is connected to the front wheel cylinders 4 and 5 through the front switching valves 2 and 3, respectively, and is connected to the rear wheel cylinders 7 and 8 through the rear switching valve 6.
connected to. The bon f9 has two bon f groups, one for the front wheels and the other for the rear wheels, and is driven by a motor. A check valve 12, 13 is provided in the middle of the pipe connecting the pump 9's discharge tal S10.11 and the Thomas Relider 1 to prevent the flow from flowing backwards to the pump 9's inlet port. The conduit connected to section 14.15 is provided with a check valve 18.19 which completely prevents the oil from flowing back into the reservoir/mass 16,17.

Therefore, as for connection #1l=19.1 of each pipe line in this system, when the communicating part 2a of the switching valve 2 faces the pipe line, the mask cylinder 1 and the foil cylinder 4 are connected, and the connecting part 2C is connected to the pipe line. When facing the road, the foil cylinder 4 and the bomb f9 are connected via the reservoir 16 and the check valve 18. On the other hand, when the blocking portion 2b of the switching valve 2 faces the pipe line, this pipe line is blocked. The other switching valves 3 and 6 also function in exactly the same manner as the switching valve 2, and these switching valves are controlled by the control circuit 20.

This control circuit 20 also controls the pump 9 and electric relief valves 21, 22, which will be described later.

The discharge part 10 and the inlet part 14 of the pump 9 are connected by a communication passage 23, and an electric relief valve 21, which is an opening/opening valve, is provided in the middle of the communication passage 23. Similarly, the discharge part 1 of the pump 9
1 and the inlet portion 15 are also connected by a communication passage 24 provided with a relaxed excitation relief valve 22'f.

FIG. 2 shows the configuration of the electric relief valve 21. In this figure, a core 31 is housed in a housing 30, and a coil 32 and a cylindrical bottle 33 are arranged around the core 31. A spool 35 having a communication hole 34 bored in its shaft center is slidably disposed inside the bottle 33, and the stool 35 is always urged upward in the figure by a spring 36. The pulp plate 37 is caulked to the upper opening of the housing 30, and a cylindrical valve seat portion 38 is formed below the pulp plate 37. A guide hole 39 is formed in the center of the pallet plate 37, and a communication hole 40 is formed in the side of the housing 30 to communicate the inside and outside of the housing. By applying a low voltage to the coil 36, the stool 35 moves downward in the figure, and the third
As shown in detail in the figure, a gap is created between the valve seat portion 38 of the valve plate 37 and the spool 35. In other words, oil flows through the gap as shown by the arrow,
This means that the communication h'' 623 is opened.The configuration of the electric relief valve 22 is also the same.

Since the anti-skid system has the above configuration, it operates as follows.

In normal brakes, the switching valves 2, 3, and 6 always have their communication parts facing into the pipe line, and the mask cylinder 1 and the foil cylinders 4+5+7+8 are directly connected, so that the hydraulic pressure generated in the mask cylinder 1 is transferred directly to the foil cylinder. 4,5,7
．． 8 to operate the brake. However, when the road surface is wet with water or on snow, if the oil pressure of the mask cylinder 1 is directly applied to the foil cylinder, the wheels will lock, causing a skid phenomenon in which the wheels slip, resulting in a significant deterioration of driving stability and braking performance. . Therefore, when a skid occurs, the control circuit 20 first sets the appropriate switching valve in a state in which the shutoff part faces the inside of the pipe line, and then moves it to a state in which the reflux part faces into the pipe line to drain the oil in the foil cylinder. Return it to the reservoir and reduce the pressure inside this foil cylinder. The oil remaining in the reservoir is pumped out by the pump 9 and discharged from the discharge part 10.11.
Paper pressure is applied to the electric relief valve 21.22 by the circuit 20, and the oil is returned to the inlet 14.15 of the pump 9 via the communication channel 23.24i. Therefore, no oil is supplied to the mask cylinder 1, and the kickback phenomenon is prevented from occurring. After that, when the internal pressure of the foil cylinder reaches an appropriate value, the switching valve opens the shutoff part to the inside of the pipe, and conversely, when the pressure is low, the communication part faces into the pipe, and when the pressure is high, the reflux part faces into the pipe. It is precisely controlled so that the appropriate foil cylinder pressure is always applied. The electric relief valves 21, 22 are energized to open the communication passages 23, 24 only when the cutoff part and the reflux part of the switching valve face the inside of the pipe line, and otherwise close the communication passages.

Now, regarding the response speed of the relief valves 21 and 22, if the switching time from closed to open is slow, the aforementioned kick-mack phenomenon will occur, and if the switching time from open to closed is slow, oil will leak from the mask cylinder during pressure increase. If you do not press the brake pedal deeply, the brakes will not work. However, in this embodiment, the lj: military relief valve is controlled by an electric signal, so the response speed is fast, and the above problem does not occur.

FIG. 4 shows the power steering system. A pulley portion 51 of the oil pump 50 is provided with gears corresponding to the number of cylinders, and an electromagnetic pickup 52 is provided adjacent to the pulley portion 51. This pickup 52
When the oil, JP-F50, rotates, it outputs a signal corresponding to several cylinders per rotation, and this signal is sent to the control circuit 53. It consists of an operating section 54c, a control pulp, a power cylinder, and a gear box, and an electric relief valve 55 similar to the above-mentioned relief valves 21 and 22 is provided between the operating section 54 and the oil pump 50.

If the electric relief valve 55 is not provided, the method shown in Fig. 5 (
As shown in b), the electromagnetic big-up f52 signal (fifth
Pressure pulsations occur in several cylinders every rotation after a delay of time T from FIG. 3(a). In this embodiment, as shown in FIG. 5(e), when there is a delay of time T1 from the signal from the electromagnetic pickup 52, the voltage is applied to the electric relief valve 24 for a time T2 (the time of the portion higher than the average pressure of the pressure pulsations). Therefore, for that period of time, the oil is released from the rotation relief valve 55.
'ff: By-passed to the pump 50, the pressure pulsations are small as shown in FIG. 5(d).

Lightning relief valve 21.2 provided in each of the above embodiments
2.55 uses 'm magnetic force, but below) 7
The one using a 1q bell piezoelectric vibrator has better responsiveness.

FIG. 6 shows the configuration of an electric relief valve 60 using a piezoelectric 5-oscillator, and is configured so that it is deflected upward in the figure by applying a voltage to the piezoelectric vibrator. There is. That is, as shown in detail in FIG.
A large number of 111. It is designed to apply pressure, and this
Distortion of about m is generated.

The piezoelectric vibrator 61 is arranged in a dish-shaped case 66 at its lower part, a seal plate 67 is fitted at its upper part, and is housed in a housing 68 in this state.

The seal plate 67 is slidably inserted into the housing 68, and a spring 70 is provided between the seal plate 67 and the seal plate 69, which closes the upper opening of the housing 68.
At the end of the year, he is sent to the lower part of the city. A communication hole 71 is bored in the center of the seal plate 67, and a communication groove 72 is formed in the inner wall.
, a chamber 73 between the case 66 and the seal plate 67 and a chamber 74 above the seal plate 67 communicate with each other. The valve body 75 is slidably fitted into a cylindrical part 76 formed on the lower surface of the cap 69, is always urged downward by a spring 77, and is attached to the seal plate 67 in the rear row 1. The inlet portion 90 formed at the top of the p1 cap 69 and the outlet portion 91 formed at the side of the housing 680 are disconnected from each other. Each spring 70. Regarding the resiliency of '17,
Spring 70 is stronger than spring 77 (approximately 1
0 times), on the other hand, J'±[i of the valve body 75 is larger than the weight of the seal plate 67 (approximately 5 times).

The core wires 64 and 65 transferred backward to the piezoelectric vibrator 61 are soldered to a hermetic seal 78, and the hermetic seal 78 is fixed to the housing 68 by a circlip 79. Note that 80, 81° and 82 are O-rings, respectively.

The electric front edge release valve 60 using the piezoelectric vibrator 61 operates as follows.

When an oval wave voltage as shown in FIG. 9 is applied to the piezoelectric vibrator 61, the piezoelectric vibrator 61 expands at time T1, and moves the valve body 75 upward in FIG. 6 via the seal plate 67. Then, when the electricity is cut off at 72 o'clock, the piezoelectric actuator 6
1 contracts, and at this time the valve body 75 tends to move downward in the figure due to the elastic force of the spring 77. However, since the spring 70 has a larger elastic force than the Suge ring 77, and the seal plate 67 is smaller than the valve body 75, the speed at which the seal plate 67 moves downward is faster than the valve body 5. (approximately 50 times) greater than the downward speed of The oil flows in the direction of the arrow and is exclusively directed to the outlet portion 91. When the voltage is applied again at 73:00, one hour after T1, the piezoelectric vibrator 61 expands to the gap gtO, and the oil spreads out. Figure 10 shows the gap g corresponding to the above voltage change.
The gap g is 1 lap! After repeated changes in JIT, the average oil gap is about half that of the Gyazo GO. /2 and flows between the valve body 75 and the sealing plate 67.

Effects similar to those described above can be obtained by using the frost front release valve having the above configuration.

Effects of the Invention As described above, according to the present invention, the kickback phenomenon and pressure pulsation can be sufficiently reduced.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing an anti-skid system in which the pulsation suppressor according to an embodiment of the present invention is applied. Fig. 4 is a sectional view of the main part of the figure.
Figure 5 (a) is a circuit diagram showing the power steering system used. Figure 5 (b) is a graph showing the output signal of the power supply valve, and Figure 5 (b) is a graph showing the pressure pulsation when there is no front side release valve.
el is a graph showing the change in the voltage applied to the front side drain valve, Figure 5 (d) is a graph showing the pressure change when the front side drain valve is provided, and Figure 6 is the graph showing the change in the voltage applied to the front side drain valve. 7 is a sectional view of the main part of FIG. 6, FIG. 8 is a perspective view of a piezoelectric vibrator, and FIG. 9 is a voltage applied to the piezoelectric vibrator. FIG. 10 is a graph showing changes in the gap between the valve body and the sealing plate. 9..., 4? 10.11...Discharge part, 14.15...Inlet t is, 23.24...
Communication path, 21.22, 55.60... Opening/closing valve ('[i
J, front edge valve). b') b3 b3 b3 Figure 9

Claims (1)

[Scope of Claims] 1. The discharge part of the pressure source that supplies pressure fluid to the operating part [~ and the inlet part are connected through a communication passage, and an on-off valve is provided in this communication passage, and this on-off valve is Operating condition of the above operating part; t
A pulsation suppressing device characterized in that it opens in response to 4'j, and causes the pressure fluid discharged from the discharge section to flow into the inlet section, thereby suppressing pulsations in the discharge pressure of the pressure fluid. 2. The opening/closing valve is characterized in that it is driven to open and close automatically.
．． +.