JP2567878Y2 - Hydraulic pressure increasing device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modulated valve (hydraulic pressure increasing valve) used for controlling the clutch hydraulic pressure of a transmission such as a truck, a bus, a construction machine, a forklift and the like.

[0002]

2. Description of the Related Art A fluid pressure increasing device disclosed in Japanese Utility Model Publication No. Sho 62-6986 will be described with reference to FIG. In the figure, reference numeral 11 denotes a valve body,
1 has an input port 17 and an output port 18 and includes a flow path a communicating between them, and a load piston pressure receiving chamber 20 extending to the left, and a portion of the flow path a of the valve body 11 includes: An operating slag pressure receiving chamber 28 communicating with a flow path a via an orifice 27 and a spool 12 provided with a throttle portion 26 formed of a slope 21 are fitted in the left and right sliding freely. The slag 16 fitted on the right side is pushed by the fluid pressure flowing into the slag pressure receiving chamber 28 from the orifice 27 through the orifice 27, and the slag 16 is moved to the left side by the reaction force. The amount of the throttle and the flow through the flow path a is reduced.

In the figure, reference numeral 22 denotes a step provided on the right side of the valve body 11, and a shoulder 29 provided on the right side of the spool 12 hits the left side of the step 22 to limit excessive left movement of the spool 12. Further, the bottom side of the load piston pressure receiving chamber 20 on the left side of the valve body 11 is connected to the output port 18 via the orifice 6 and the oil passages 9, 23 and 24 via the oil passage 8 which communicates with the output port 18. A load piston 13 is inserted into the piston pressure receiving chamber 20 so as to be movable left and right, and the load piston 13 is connected to a bottom side of the load piston pressure receiving chamber 20 through an oil passage 24 through an exhaust passage 19.
Is biased by a spring 15 interposed between itself and the spool 12 so as to discharge the internal fluid when the is opened.

When the discharge passage 19 is closed, the pressure in the load piston pressure receiving chamber 20 causes the load piston 1 to move.
3 moves to the right while compressing the spring 15, and pushes the stop rod 14 protruding from the spool 12 to move the spool 12 to the right. Further, the discharge path 19 is provided with an electromagnetic valve 30 including a coil 31, a permanent magnet 32, and a plunger 33 for opening and closing the discharge path 19, and the electromagnetic valve 30 responds to an electric signal from an electric control unit (not shown). It operates as a proportional solenoid valve, and generates a magnetic field of the coil 31 by energization by an electric signal, moves the plunger 33 to the right by the repulsive force with the permanent magnet 32, and closes the discharge path 19, and the repulsive force is It can be changed by the strength of the current.

[0005] When used in a hydraulic pressure passage for switching a clutch,
An oil passage 7 on the discharge side of the oil pump 1 having the regulator valve 2 is connected to an input port 17 and an output port 18.
Is connected to both cylinders of the clutches 4 and 5 via the shift valve 3.

[0006]

The above prior art has the following problems. If the pressure required to supply oil to the clutches 5, 4 downstream of the hydraulic pressure increasing valve 10 is higher than the initial pressure of the hydraulic pressure increasing valve 10 (D in FIG. 3),
The oil filled in the clutch cylinders 5, 4 is gradually increased.
Since it is sent while being throttled by 0, it takes time, and the oil pressure rises rapidly at the same time as the filling is completed.

The above problem will be described in more detail. In the case of the gradual increase valve, if the pressure in the oil passage 8 is equal to or less than the initial set pressure, the oil pressure acting on the spool 12 is smaller than the force of the spring 15, and as shown in FIG.
6 is pressed to the right in the figure, and since the port 17 and the port 18 communicate without being throttled, the pressure oil from the pump 1 is sent to the full flow clutch cylinders 5, 4. However, when the temperature is low, the viscosity of the oil increases and the oil passage 5
Since the pressure loss at 0,51 also increases, the pressure in the oil passage 8 may be higher than the initial set pressure of the valve. At this time, the filling of the clutch cylinders 5 and 4 is performed while the pressure is adjusted by the spool 12 to an oil pressure balanced with the force of the spring 15, so that it takes more time than usual. Further, the load piston 13 gradually moves to the right in the figure by the oil passing through the orifice 6 and pushes the spring 15, so that the set pressure increases regardless of the pressure of the oil passage 8. When the filling of the clutch cylinders 5 and 4 is completed, the pressure in the oil passage 8 increases until the force of the spring 15 is balanced, and the clutch is suddenly engaged, so that a shock occurs.

The present invention solves the above-mentioned problems of the prior art.
It is an object of the present invention to provide a hydraulic pressure increasing device capable of stopping the movement of the load piston 13 so that the communication of the load piston 8 can be performed without reducing the pressure and the sudden increase in pressure at the end of filling does not occur. .

[0009]

As shown in FIG. 1, a pressure regulating valve 60 is provided between the load piston pressure receiving chamber 20 and the oil passage 8 on the output port 18 side.
Stop the operation of, and suppress the rise of the set hydraulic pressure of the gradually increasing valve,
Further, the pressure of the slag pressure receiving chamber 28 is reduced so that the oil can be sent to the clutch cylinder 5 or 4 without being throttled on the way by the spool 12.

[0010]

When the pressure required to fill the clutch cylinder 4 or 5 is higher than the initial set pressure of the hydraulic pressure increasing valve, the operation of the pressure adjusting valve 60 keeps the load piston 13 in a stopped state, and the set oil pressure of the pressure increasing valve increases. Is suppressed.
Also, the pressure in the slag pressure receiving chamber 28 decreases, and the spool 12 keeps the ports 17 and 18 open.

[0011]

1 to 6 show an embodiment of the present invention. In the figure, 1 is an oil pump, 2 is a regulator valve, 3 is a shift valve, 4, 5 are clutch cylinders, 6, 27 are orifices, 7, 8, 9, 50, 51,
52 and 53 are oil passages, 10 is a hydraulic pressure increasing valve (entire), 1
1 is a valve body, 12 is a spool, 13 is a load piston, 14 is a stop rod, 15 is a spring, 16
Is a slag, 20 is a load piston pressure receiving chamber, 28 is a slag pressure receiving chamber, 30 is a solenoid valve, 31 is a coil, 32 is a permanent magnet, 33 is a plunger, 60 is a pressure regulating valve (entire), 6
1, 62 are fitting holes, 63 is a spool, 64 is a slug, 6
5 is a spring, 66 is a pressure receiving chamber, 67 and 68 are ports,
69 is a drain port, 70 is a slag pressure receiving chamber, 71 is a valve body, 111 and 112 are fitting holes, 17, 18, and 11.
3 is a port, and 114 and 51 are drain ports.

1 and 2 use the same reference numerals for the same members as in the prior art (FIG. 7).
The hydraulic pressure increasing valve 10 has fitting holes 111 and 112,
A spool 12, a slug 16, and a load piston 13 that can freely slide therein are incorporated therein. The fitting hole 111 is provided with concentric ports 51, 17 and 18, and a load piston pressure receiving chamber 20, and communicates with the drain, the oil passage 7, the oil passage 8 and the oil passage 24, respectively. Mating hole 1
12 also has a concentric slag pressure receiving chamber 28, which communicates with the oil passage 53. The spool 12 in the fitting hole 111 has a groove on the circumference, and the ports 18 and 17 are intermittently connected. A stop rod 14 is mounted on the right side in the drawing, and the spool 12 and the stop rod 14 Is designed to move in unison. The load piston 13 is set in the fitting hole 111 so as to face the spool 12, and a spring 15 is assembled between the load piston 13 and the spool 12 and guided by a stop rod 14. When the rightward movement of the load piston 13 is completed, the load piston 13 comes into contact with the stop rod 14, and the spool 12 and the slug 112 are also pressed to the right end.

The solenoid valve 30 includes a permanent magnet 32, a coil 3
1. The plunger 33 is connected and disconnected between the oil passage 24 and the discharge passage 19 by turning on / off the coil 31. The pressure regulating valve 60 has fitting holes 61 and 62, in which a spool 63 that can be freely and slidably moved.
A slug 64 is incorporated, and a spring 65 is also set to the right of the slug 64. The fitting hole 61 is provided with a concentric pressure receiving chamber 66 and ports 67, 68, 69, which communicate with the oil passages 9, 52, 53, respectively. On the spool 63, a groove for intermittently connecting the pressure receiving chamber 66 and the port 67, and the ports 67 and 68 is provided. The pressure receiving area ratio between the spool 63 and the slag 64 is
And the area ratio of the slag 16 are set to be approximately the same.

Pump 1 and port 1 of hydraulic pressure increasing valve 10
7 is in communication with the oil passage 7 and the regulator valve 2
Also communicates with the oil passage 7. The port 18 communicates with the pressure receiving chamber 65 of the pressure regulating valve 60 and the shift valve 3 by the oil passage 8, and from the shift valve 3 to the clutch cylinder 5 or 4 via the oil passages 50 and 54, respectively. The oil passage 8 is connected to the pressure regulating valve 60 through the orifice 6 and the oil passages 9, 23, 24.
And the load piston pressure receiving chamber 20 of the hydraulic pressure increasing valve 10. Further, the oil passage 8 has the orifice 2
7. The oil passage 53 communicates with the port 68 of the pressure regulating valve 60 and the slag pressure receiving chamber 28 of the hydraulic pressure increasing valve 10. The port 67 of the pressure regulating valve 60 and the port 113 of the hydraulic pressure increasing valve 10 communicate with each other through the oil passage 52.

The pressure oil from the pump 1 is regulated by the regulator valve 2 and sent to the port 17. The pressure adjusted at this time is referred to as a main hydraulic pressure. The hydraulic pressure gradually increasing valve 10 has an operation of gradually increasing the oil pressure of the clutch cylinders 5 and 4 to the pressure of the port 17 and gradually engaging the clutch when switching the clutch. (The oil pressure in the oil passage 8 is hereinafter referred to as a clutch oil pressure.) The function will be described below.

When the clutch is switched, the solenoid valve 30 is operated by a control device (not shown) to connect the oil passage 24 and the discharge passage 19, and the load piston 13 for discharging the oil in the load piston pressure receiving chamber 20 is discharged. Is returned to the left end as shown in FIG. 1 (point B in FIG. 3). When the discharge of the oil from the load piston pressure receiving chamber 20 is completed, the solenoid valve 30 is deactivated and the oil passage 24 and the discharge passage 19
Is shut off. When the filling of the clutch cylinder 5 or 4 is completed, hydraulic pressure is generated at the output port 18 so that hydraulic pressure acts on the slag 16. When the force exceeds the spring 15 force, the spool 12 is moved to the left, and the ports 17 and 18 are shut off. Therefore, the increase in the oil pressure in the oil passage 8 stops (D in FIG. 3).
point). On the other hand, the oil also flows into the load piston pressure receiving chamber 20 via the orifice 6, moves the load piston 13 to the right and compresses the spring 15, so that the spring force increases, and the clutch oil pressure rises until it is balanced (FIG. 3). Between D and E). When the load piston 13 moves to the right until it hits the stop rod 14, the spool 12 is pushed to the right at once and the ports 17 and 18 are completely connected, so that the clutch oil pressure rises to the main oil pressure and the pressure adjusting operation ends (FIG. F point 3). In the normal case, the pressure ratio between the load piston pressure receiving chamber 20 and the slag pressure receiving chamber 28 is equal to the ratio between the cross-sectional area of the load piston 13 and the cross-sectional area of the slag 16. While being pushed to the middle left, the modulating valve 10 operates in the same way as in the prior art.

At low oil temperature, when the filling pressure of the clutch cylinder becomes higher than the initially set pressure (point D in FIG. 3) of the hydraulic pressure gradually increasing valve 10 due to an increase in pipeline resistance or the like (FIG. 4).
(Point G), the oil to the clutch cylinder is throttled by the spool 12, so that the filling time is long, and the clutch pressure is kept constant until the filling is completed (GI in FIG. 4).
while). However, conventionally, since the clutch pressure is higher than the pressure of the load piston pressure receiving chamber 20, oil flows into the load piston pressure receiving chamber 20 through the orifice 6, and the load piston pressure receiving chamber 20 is kept at the same pressure as the clutch oil pressure. Since the pressure increases, the clutch pressure increases until the pressure in the load piston pressure receiving chamber 20 is balanced with the completion of the filling of the clutch cylinder (point H in FIG. 4), which may cause a large shift shock. The pressure regulating valve 60 is provided to solve this problem. When the pressure ratio between the load piston pressure receiving chamber 20 and the slag pressure receiving chamber 28 becomes equal to or greater than a set value, the pressure receiving area of the pressure receiving chamber 66 becomes smaller than that of the slag pressure receiving chamber 70. Since it is larger than the pressure receiving area, the hydraulic pressure acting on the pressure receiving chamber 66 becomes larger than the sum of the hydraulic pressure acting on the slag pressure receiving chamber 70 and the spring force, and the spool 63 is moved to the right until the state shown in FIG. 9 and the port 52 are communicated, and the oil in the load piston pressure receiving chamber 20 is supplied to the pressure receiving chamber 66 and the port 6.
7. Drain from oil passage 52, ports 113 and 114,
The pressure in the load piston pressure receiving chamber 20 is kept constant (between G ′ and H ′ in FIG. 5). At this time, since the port 68 and the port 52 also communicate with each other, the pressure in the slag pressure receiving chamber 28 decreases, and the spool 12 moves to the right to completely communicate the port 17 and the port 18, thereby shortening the filling time (FIG. 6). The above operation is performed when the following conditions are satisfied.

[0018] When the filling is completed and the clutch oil pressure starts to rise, the spool 63 of the pressure regulating valve 60 moves to the left and the pressure receiving chamber 66
And the port 67 and the port 67 and the port 68 are shut off, and the operation is terminated. When the load piston 13 further moves to the right and hits the stop rod 14, the load piston 13
Pushes the spool 12 to the right, and the ports 17 and 18
Are completely communicated, and the hydraulic pressure increasing operation is completed (E in FIG. 5).
-F). At this time, the port 113 is connected to the load piston 13
As a result, the pressure in the load piston pressure receiving chamber 20 increases to the clutch hydraulic pressure even when the pressure regulating valve 60 is operated.

[0019]

According to the present invention, there is provided a valve body having a flow passage communicating with an input / output port and a load piston pressure receiving chamber, and the flow passage inserted through an orifice inserted into a portion of the flow passage in the valve body. A spool provided with an operating pressure receiving chamber and a throttle portion of the flow path, which are connected to the output port side, and which is fitted into the load piston pressure receiving chamber which is connected to the output port side, discharges an internal fluid when the discharge path is opened, and discharges the internal fluid. A spring-biased load piston for releasing the throttle of the spool when the pressure rises, a stop rod protruding from the spool and opposed to the load piston, and a proportional for opening and closing the discharge passage and controlling the throttle. The following effects are obtained by providing the pressure regulating valve between the load piston pressure receiving chamber and the oil passage on the output port side in the modulate valve including the solenoid valve.

The pressure regulating valve allows the ports 17 and 18 of the spool 12 to be filled with the clutch under any conditions.
Communicate with each other to enable filling in the shortest time, and at the same time, abrupt pressure at the end of filling is eliminated, so that smooth engagement performance can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration and an initial state of a hydraulic pressure increasing device according to the present invention.

FIG. 2 is a diagram showing a state at the end of a hydraulic pressure increasing operation of the hydraulic pressure increasing device in FIG. 1;

FIG. 3 is a diagram showing a normal hydraulic pressure waveform of a hydraulic pressure increasing valve.

FIG. 4 is a diagram showing a hydraulic pressure waveform when a problem occurs in a conventional hydraulic pressure increasing valve.

FIG. 5 is a diagram showing a hydraulic pressure waveform by the device shown in FIG.

FIG. 6 is a view showing an operation state of the pressure regulating valve shown in FIG. 1;

FIG. 7 is a diagram showing a configuration of a conventional device.

[Explanation of symbols]

 10 Hydraulic pressure increasing valve 17 port 18 port 60 Pressure regulating valve

Claims (1)

(57) [Scope of request for utility model registration] 1. A valve body having a flow passage communicating with an input / output port and a load piston pressure receiving chamber, and an operation inserted into a portion of the flow passage in the valve body and connected to the flow passage through an orifice. And a spool provided with a pressure receiving chamber and a throttle portion of the flow path, and fitted into the load piston pressure receiving chamber communicated with the output port side to discharge the internal fluid when the discharge passage is opened, and the internal fluid pressure has increased. Sometimes a spring-biased load piston that releases the throttle of the spool, a stop rod protruding from the spool and opposed to the load piston, and a proportional solenoid valve that opens and closes the discharge passage and controls the throttle. A pressure increasing valve provided between a load piston pressure receiving chamber and an oil passage on an output port side in a modulated valve provided.