JPH0125804Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention aims to gradually increase the pressure of the pressure fluid supplied from the directional control valve to the hydraulic clutch at the initial stage of its delivery, thereby smoothing the connection of the hydraulic clutch. The present invention relates to a modulator valve.

[Prior art]

Generally, the modulator valve a is provided in communication with a pipe line e branched from the discharge pipe line d of the directional switching valve device b, as shown in FIG. 1, and the function of the valve a is to At the initial stage of operation of the directional switching valve device b, which sends out the pressure fluid from the oil pump p and has been regulated to a constant pressure by the regulator valve r, to the hydraulic clutch f with the shift of the change lever b'. A portion of the fluid is released to the side of the fluid tank t to alleviate the increase in fluid pressure to the hydraulic clutch f, thereby allowing smooth connection to forward or reverse drive. More specifically, in the initial stage of operation of the directional valve b, the pipes d, e, and 1
1 to the first pressure liquid chamber 10, and moves the spool 5 to return the pressure oil in the first pressure liquid chamber 10 to the tank t via the port 12. This prevents a sudden pressure rise and allows smooth connection during forward or reverse drive.

However, with such conventional modulating valves, as the oil temperature rises, the viscosity decreases and the amount of outflow from port 12 increases, causing a change in the rising speed waveform of the hydraulic pressure applied to the hydraulic clutch. However, there was a drawback that the clutch slipped for a long time, resulting in poor starting characteristics of the vehicle.

[Purpose of invention]

The present invention aims to solve the above-mentioned drawbacks of the conventional technology, and is to create a modulator that can change the connection state of the hydraulic clutch according to the viscosity of the oil, thereby always providing the optimum starting feeling. The aim is to provide valves.

[Structure of the idea]

In the present invention, a valve spool is fitted into one side of a long hole formed in a valve body, and a piston is fitted into the center of the long hole coaxially with the valve spool, thereby connecting the valve spool and the piston. A spring means is interposed between the flow grooves provided on the outer periphery of the valve spool and the circumferential wall of the elongated hole to form a first pressure liquid chamber communicating with the discharge side conduit of the directional switching valve device; A discharge port communicating with the first pressure liquid chamber at the pushing position of the valve spool is provided in the valve body, and a second pressure liquid chamber adjacent to the piston is provided on the other side of the valve body, and the directional switching valve is provided. A modulator valve, wherein a partition wall is provided to partition a liquid reservoir chamber communicating with a discharge pipe of the device, and a passageway communicating between the second pressure liquid chamber and the liquid reservoir chamber is formed in the partition wall. A throttle rod is provided in the chamber such that the base end is fixed to the valve body and the tapered portion formed at the free end is located within the passage of the partition wall, and the throttle rod is made of a material with a large coefficient of thermal expansion. However, the gist of the present invention is that the spacing between the tapered portion and the passage can be increased when the oil temperature rises.

Here, the drawing rod is made of a material with a large coefficient of thermal expansion, preferably a metal such as zinc. Note that the entire drawing rod does not necessarily need to be made of a material with a large coefficient of thermal expansion; the end portion may be made of ordinary steel, but the shaft portion, which occupies most of the volume, must be made of the above-mentioned material.

[Effect of idea]

According to the present invention, the throttle rod expands and contracts in response to the temperature of the oil, thereby controlling the engagement of the hydraulic clutch, so that an optimal starting feeling can always be obtained.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the modulator valve a in Fig. 1,
Reference numeral 1 denotes a valve body, which has a long hole coaxially communicating with a small diameter hole 2 on the left side in the figure, a long large diameter hole 3 in the center, and a medium diameter hole 4 on the right side. It is being Reference numeral 5 denotes a valve spool, the left half of which is fitted into the small diameter hole 2, the fitting shaft part 6 having a small flow groove 7 formed in the middle thereof, and the right half of the valve spool having a shaft inserted into the large diameter hole 3. A collar piece 9 for receiving a spring is formed between the portion 8 and the portion 8. The fitting shaft portion 6 has a small diameter hole 2
A first pressure liquid chamber 10 is formed between the left end of the fitting shaft portion 6 and the peripheral wall of the small diameter hole 2. Reference numeral 10' denotes a cushion chamber, which communicates with the first pressure liquid chamber 10 through a diagonal communication hole 6', and serves to prevent negative pressure when the valve spool 5 moves to the right and prevent sudden movement when it moves to the left. .

The wall surface of the small diameter hole 2 of the valve body 1 has a first
A port 11 communicating with the first pressure liquid chamber 10 in the illustrated state
and a discharge port 12 which is closed on the outer peripheral surface of the fitting shaft portion 6 on the right side of the port 11.

The port 11 communicates with a conduit e branched from the discharge conduit d of the directional valve device b, and the discharge port 12 communicates with the liquid tank t.

Inside the large diameter hole 3 is a piston 13 having a cylindrical shape with a bottom.
is fitted into the flange piece 9 of the valve spool 5;
A compression coil spring 14 is interposed between the piston 13 and the bottom wall.

On the wall surface of the large diameter hole 3, there is a port 16 that communicates with the left side cavity of the collar piece 9 to allow movement of the spool 5 and the piston 13, and a port 16 that communicates with the left side space of the collar piece 9 and the piston 13.
A port 17 communicating therebetween is provided so as to communicate with the liquid tank t.

Further, the medium diameter hole 4 has a bottom wall 21.
An exhaust valve spool 20 having a center hole 22 in the center thereof is fitted, and a compression coil spring 25 is fitted between the bottom wall surface of the spool 20 and the right wall surface of the medium diameter hole 4.

By this spring 25, the bottom wall 21
is pressed against the snap spring 26 fitted on the left circumferential surface of the medium diameter hole 4, and the top surface of the piston 13 and
A second pressure liquid chamber 23 is formed between the bottom wall 21 and a liquid storage chamber 24 is formed between the right end wall of the medium diameter hole 4 and the bottom wall 21. The liquid reservoir chamber 24 communicates with the liquid reservoir chamber 24 (the bottom wall 21 of the spool 20 forms a partition between the second pressure liquid chamber 23 and the liquid reservoir chamber 24).
Further, on the wall surface of the medium diameter hole 4, there is a port 18 that is closed by the outer peripheral surface of the spool 20 in the state shown in FIG.
A port 19 communicating with the liquid reservoir chamber 24 is provided on the right side thereof, and the port 18 is connected to the liquid tank t, and the port 19 is connected to the liquid tank t.
Similarly to the port 11, they communicate with the pipe e.

The center hole 22 is located in the center of the liquid reservoir chamber 24.
A diaphragm rod 30 is installed so as to pass through the diaphragm 30.
The throttle rod 30 has its base end fixed to the portion 1a of the valve body 1, and its free end is formed with a tapered portion 31 whose diameter increases toward the tip. The drawing rod 30 is made of a metal with a large coefficient of thermal expansion, such as zinc, and in the illustrated state, the center hole 22 is in an open state, but when the drawing rod 30 is contracted, a tapered portion is formed. 31 narrows the passage of the center hole 22.

Next, the operation of this embodiment will be described.

By shifting the change lever b', pressure fluid flows out from the directional valve device b into the discharge line d, so that pressure fluid flows into the port 11 and the port 19 of the modulator valve a from the line e.

By the way, in the second pressure liquid chamber 23 which communicates with the port 19 through the center hole 22, the pressure increase is gradual because the passage of the center hole 22 is narrow.
Since the pressure in the first pressure liquid chamber 10 communicating with the port 11 increases rapidly, the pressure difference causes the valve spool 5 to
is moved to the right in FIG. 1 against the spring 14, and since the ports 11 and 12 communicate with each other through the flow groove 7, a part of the pressure fluid escapes to the liquid tank t.

The pressure fluid flowing into the second pressure liquid chamber 23 from the center hole 22 flows through the center hole 22 and the tapered portion 31 of the throttle rod 30.
The moving speed of the piston 13 is extremely slow, and the movement speed of the piston 13 is extremely slow.
The internal pressure of the clutch f becomes a hydraulic pressure corresponding to the reaction force of the spring 14, so when the spring 14 is compressed by the movement of the piston 13, the internal pressure of the second pressure fluid chamber 23 gradually increases, and the second pressure is applied to the clutch f. Pressure liquid chamber 23
Since a hydraulic pressure equal to the internal pressure of clutch f
will be connected smoothly.

After the clutch f is connected, the piston 13 finally returns the valve spool 5 to the left, returning to the position in FIG. and close port 12.

Thereafter, when the change lever b' is shifted to the neutral position, the flow of pressure fluid is stopped by the action of the directional control valve b, and the piston 13 returns to the right in the figure by the elastic force of the spring 14.

This return movement of the piston 13 to the right increases the pressure in the second pressure liquid chamber 23, but this pressure causes the spool 20 to move to the right against the small spring 25, opening the port 18 to the second pressure liquid chamber 23. In order to communicate with the chamber 23 and release the pressure fluid to the liquid tank t, the state shown in FIG. 1 is returned.

The pressure fluid flowing into the ports 11 and 19 through the pipe e has a high viscosity because the oil temperature is low at the beginning of operation, but as time passes, the oil temperature increases and the viscosity decreases. For this reason, at the beginning of operation, the throttle rod 30
is in a contracted state, and the passage of the center hole 22 is narrowed by the tapered portion 31 (the passage width is not zero). Then, as time passes after the start of operation, the oil temperature rises and the viscosity decreases as described above. In this case, in the conventional device, the amount of oil flowing out from the discharge port increases, making it difficult for the oil pressure of the hydraulic clutch f to rise (the second
Curve B) in the figure, in the present invention, the distance between the center hole 22 and the tapered part 31 is widened, and the amount that compensates for the amount of leakage from the piston flows into the second pressure fluid chamber 23, so the oil temperature rises the same as when the oil temperature is low. velocity is obtained (curve A in Figure 2). In other words, the starting characteristics of the vehicle are always constant regardless of changes in oil viscosity.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an embodiment of the present modulator valve when installed in a torque converter vehicle, and FIG. 2 is a graph showing the relationship between time after shifting and oil pressure. a... Modulator valve, 5... Valve spool, 10... First pressure liquid chamber, 13... Piston,
20...Exhaust valve spool, 23...
Second pressure liquid chamber, 30... Throttle rod, 31... Taper portion.

Claims (1)

[Claims for Utility Model Registration] (1) A valve spool is fitted into one side of a long hole formed in the valve body, and a piston is fitted coaxially with the valve spool into the center of the long hole. a spring means is interposed between the valve spool and the piston, and the first valve is connected to the discharge side conduit of the directional switching valve device through a flow groove provided on the outer periphery of the valve spool and a peripheral wall of the elongated hole.
A discharge port forming a pressure fluid chamber and communicating with the first pressure fluid chamber at the pushing position of the valve spool is provided in the valve body, and a second pressure fluid chamber adjacent to the piston is provided on the other side of the valve body. A module is provided with a partition wall that partitions a liquid chamber and a liquid reservoir chamber that communicates with a discharge pipe of the directional switching valve device, and a passage that communicates the second pressure liquid chamber and the liquid reservoir chamber is formed in the partition wall. In the Urator valve, a throttle rod is provided in the liquid storage chamber, the base end of which is fixed to the valve body, and a tapered portion formed at the free end is located within the passageway of the partition wall, and the throttle rod is heated. 1. A modulator valve, characterized in that it is made of a material with a large coefficient of expansion, and the gap between the tapered portion and the passage increases when oil pressure increases. (2) The modulator valve according to claim 1, wherein the material having a large coefficient of thermal expansion is a metal such as zinc.