JPH0567879U - Spool valve - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the system responsiveness by increasing the supply amount to the actuator. [Structure] The first and second ports 6, which are opened and closed by the land portion 10 with respect to the length L of the land portion 10 of the spool 2,
The diameter D ₄ of either one of the ports 7 is increased. Then, the first and second portions opened and closed by the land portion 10 with respect to the length L of the land portion 10 of the spool 2.
The diameter D ₄ of either one of the ports 6 and 7 is about 1.
It is preferable to set 5 times as the upper limit.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a spool valve used for controlling various oils, pneumatic equipment, etc.

[0002]

[Prior Art]

 A conventional spool valve of this type is, for example, one as shown in FIG. That is, this spool valve is a three-way valve in which the spool 100 slides to switch the pressure, and the spool 100 is slidably inserted into the inner circumference of the guide hole 102 of the valve body 101. The valve body 101 is provided with a second port 103 on the output side to the actuator, a first port 104 on the supply side to which pressure oil is supplied from a pressure source, and a discharge port 105. The solenoid 106 moves back and forth to open and close the second port 103 by the land portion 107 of the spool 100 so that the pressure from the first port 104 is selectively supplied to the second port 103. There is.

The second port 103, which is a pressure switching unit, is set so that the land 107 of the spool 100 causes a closed state during operation as shown in FIG. 6B, and the solenoid 106 is in an OFF state. As shown in FIG. 6A, the second port 103 and the discharge port 105 are in communication with each other, and the hydraulic pressure on the actuator side is in a discharged state. When the solenoid 106 is turned on, as shown in FIG. Is moved and the second port 103 leading to the discharge port 105 side is closed by the land portion 107, and the side to which the pressure is supplied is gradually opened.

Further, the actuator operates due to fluctuations in the flow rate, and particularly when the hydraulic pressure is low {29.4N (3 kgf / cm ² )}, the responsiveness becomes faster as the supplied or discharged flow rate increases. It will improve.

[0005]

[Problems to be solved by the device]

 However, in the case of the above-mentioned conventional technique, the number of ports must be increased or the stroke of the spool 100 must be increased in order to improve the flow rate to be supplied or discharged, and there is a drawback that the cost and size must be increased. ..

The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object thereof is to provide a spool valve capable of improving system responsiveness by increasing the supply amount to an actuator. It is in.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, in the present invention, a valve body having a guide hole therein, a spool slidably inserted into an inner circumference of the guide hole of the valve body, and the valve body are provided. The first port, the second port, and the discharge port are provided, and when the spool moves, either one of the first port and the second port is opened and closed at the land portion of the spool to open the first port. In a spool valve that selectively communicates between any one of the first port and the second port that is opened and closed by the land portion and the discharge port between the second port, and the length of the land portion of the spool. It is characterized in that the diameter of either one of the first and second ports opened and closed by the land portion is increased.

It is preferable that the diameter of either one of the first and second ports opened and closed by the land portion of the spool is set to about 1.5 times as the upper limit with respect to the length of the land portion of the spool. Is.

[0009]

[Action]

 In the spool valve configured as described above, the diameter of either one of the first and second ports opened and closed by the land portion is made larger than the length of the land portion of the spool. The area becomes large and the flow rate at the time of supply or discharge increases. Therefore, the response of the actuator on the output side of the port can be improved.

[0010]

【Example】

 The present invention will be described below based on the illustrated embodiment. In FIG. 1, which shows a spool valve according to an embodiment of the present invention, reference numeral 1 denotes the entire spool valve. In this embodiment, a spool 2 is driven by using an electromagnetic attraction force of a solenoid 3 and is transferred to an actuator. The solenoid valve is configured to switch the supply of pressure.

A schematic configuration of the spool valve 1 includes a spool 2, a valve sleeve 5 as a valve body having a guide hole 4 into which the spool 2 is inserted, and a solenoid 3 for reciprocally driving the spool 2. Has been done.

The valve sleeve 5 is an exhaust port continuously provided coaxially with the first port 6, the second port 7 and the guide hole 4 which are provided on the cylindrical side wall and are axially separated from each other by a predetermined distance. It has three ports of eight.

On the other hand, an annular groove 9 is provided on the outer periphery of the spool 2, and the first port 6 on the supply side for supplying pressure from a pump (not shown) as a pressure source is always groove 9. The second port 7 that opens toward the actuator and supplies or discharges the fluid on the output side to the actuator is opened and closed by the land portion 10 on the tip side of the concave groove 9 of the spool 2, and the second port 7 and the discharge port. 8 to communicate the fluid from the actuator to the discharge port 8 or to communicate the second port 7 and the first port 6 through the groove 9 and the pressure from the first port 6 to the actuator via the second port 7. Supply pressure to or switch to.

The diameter D ₄ of the second port 7 is larger than the length L of the land portion 10 of the spool 2 that switches the pressure.

Here, the solenoid 3 as an electromagnetic actuator for reciprocally driving the spool 2 will be described. The solenoid 3 is integrally assembled with the valve sleeve 5. That is, the solenoid 3 has a cylindrical core 11 having one end facing the valve sleeve 5 and functioning as a fixed iron core, a coil 12 arranged so as to surround the core 11, and a core 11 on the inner circumference of the coil 12. A plunger 13 which is reciprocally inserted coaxially with the coil 12, a case 14 for housing the coil 12, and a connector 15 for energizing the coil 12 are provided. A rod 16 is reciprocally inserted into the core 11, one end of the rod 16 is connected to the plunger 13 in the solenoid 3, and the other end is connected to the spool 2 in the valve sleeve 5.

Inside the valve sleeve 5, there is provided a spring 17 for urging the spool 2 toward the solenoid 3 side. 2 to separate the plunger 13 from the core 11, and the land portion 10 of the spool 2 communicates the second port 7 and the discharge port 8 as shown in FIG. 2 (a) so that the pressure on the actuator side is discharged. ..

On the other hand, when the solenoid 3 is turned on, the plunger 13 is magnetically attracted to the core 11 against the spring force of the spring 17, and the land 2 is moved by moving the spool 2 via the rod 16. However, during this operation, the diameter D ₄ of the second port 7 is larger than the length L of the land portion 10 of the spool 2 during the so-called pressure switching, so that as shown in FIG. The open state is caused by 10, and the three ports of the first port 6, the second port 7, and the discharge port 8 are in communication with each other, and by further stroke, the second port 7 and the discharge port 8 are discharged as shown in FIG. 2 (c). The output port 8 is closed, the first port 6 and the second port 7 are communicated with each other, and fluid pressure such as hydraulic pressure from the first port 6 is supplied to the actuator through the second port 7.

In the spool valve having the above-described configuration, the diameter D ₄ of the second port 7 is made larger than the length L of the land portion 10 of the spool 2, so that the solenoid valve can be turned on and off when the solenoid valve is turned on. Since the opening area of the 2-port 7 increases and the flow rate at the time of supply or discharge increases, the operation response of the actuator improves.

Since the diameter D ₄ of the second port 7 becomes larger than the length L of the land portion 10 of the spool 2, the land portion 10 causes an open state during operation, and the first port 6, Since the three ports of 2 port 7 and discharge port 8 are in communication with each other, a fluid flow occurs between them, and the operation delay of solenoid 3 is delayed on the return side (ON → OFF) of solenoid 3. It can happen.

Therefore, how much the diameter D ₄ of the second port 7 may be increased relative to the length L of the land portion 10 of the spool 2, the outer diameter D _{1 of the} spool 2 shown in FIG. Using the test spool 2 having an inner diameter D _{2 of} 5 mm, a hole 21 diameter D _{3 of} 3 mm, and a land portion length L of 4.4 mm, the land portion 10 of the spool 2 is used under the following conditions. The change in the actuation response of the solenoid 3 due to the change in the diameter D ₄ of the second port 7 with respect to the length L of was examined. The condition is that the fluid is engine oil, type: 10W-30, temperature: 80 ° C, viscosity: 80 ° C, 16.0 cst, specific gravity: 0.815, fluid supply pressure: 6 kgf / cm ² , suction of solenoid 3. Force: about 400 gf at the start of operation, and spring force of the spring 17 in the valve sleeve 5: set force 180 gf.

The abscissa indicates the diameter D ₄ of the second port 7 / the length L 1 of the land portion 10 of the spool 2, that is, the diameter D ₄ of the second port 7 with respect to the length L of the land portion 10. The graph is shown in FIG. 4, where the magnification is used and the vertical axis is the operation response of the solenoid 3 on the return side (ON → OFF).

From this graph, up to about 1.3 times the diameter D ₄ of the second port 7 with respect to the length L of the land portion 10, there is no operational response of the solenoid 3 on the return side which is 1 times that of the conventional one. There is no change, and there is an extreme delay in operation on the return side at about 1.5 times, and since this delay in operation directly delays the system, it is considered not to be slow in operation in the system. Therefore, the diameter D ₄ of the second port 7 can be increased up to about 1.5 times the length L of the land portion 10 of the spool 2, and preferably has no change from the actuation response of the conventional solenoid. It is preferable to set the flow rate to about 1.3 times, and there is an effect of increasing the flow rate when supplying or discharging the actuator in a usage state where the fluid supply pressure is low (about 58.8 N (6 kgf / cm ² ) or less).

In the above embodiment, the solenoid 3 is used as the driving means for the spool 2, but the means for driving the spool 2 is not limited to the solenoid, and other fluid pressure such as hydraulic pressure may be used. The same can be applied to those using.

[0024]

[Effect of the device]

 The present invention has the above-described configuration and operation. Since the diameter of either one of the first and second ports opened and closed by the land portion is made larger than the length of the land portion of the spool, The opening area of one of the ports becomes large, and the flow rate at the time of supply or discharge to the actuator on the output side of the port that is opened and closed by the land without increasing the number of ports or increasing the stroke of the spool increases, The system response is improved by improving the operation response of the user.

[Brief description of drawings]

FIG. 1 is an overall vertical cross-sectional view of a spool valve according to an embodiment of the present invention.

2 (a) is a longitudinal sectional view of an essential part of the spool valve of FIG. 1 when a solenoid is OFF, FIG. 2 (b) is a longitudinal sectional view of an essential part in the middle of operation, and FIG. 2 (c). Is solenoid ON
FIG.

FIG. 3 is a second diagram of the length of the land portion of the spool.
FIG. 5 is a vertical cross-sectional view of a test spool for investigating a change in actuation response of a solenoid due to a change in port diameter.

FIG. 4 is a second view of the length of the land portion of the spool.
6 is a graph showing a change in actuation response of a solenoid due to a change in port diameter.

FIG. 5 is an overall vertical sectional view of a conventional spool valve.

6 (a) is a longitudinal cross-sectional view of the main part of the spool valve of FIG. 5 when the solenoid is OFF, FIG. 6 (b) is a vertical cross-sectional view of the main part during operation, and FIG. 6 (c). Is solenoid ON
FIG.

[Explanation of symbols]

 1 Spool Valve 2 Spool 21 Hole 3 Solenoid 4 Guide Hole 5 Valve Sleeve (Valve Body) 6 1st Port 7 2nd Port 8 Discharge Port 9 Recessed Groove 10 Land Part 11 Core 12 Coil 13 Plunger 14 Case 15 Connector 16 Rod 17 Spring

Claims (2)

[Scope of utility model registration request] 1. A valve body having a guide hole inside, a spool slidably inserted into an inner circumference of the guide hole of the valve body, a first port, a second port, and a discharge port provided in the valve body. A first opening / closing between the first and second ports and a land portion by opening / closing either one of the first port and the second port at the land portion of the spool by moving the spool. A spool valve that selectively communicates between any one of the second port and the discharge port, any one of the first and second ports opened and closed by the land portion with respect to the length of the land portion of the spool. Spool valve characterized by increasing the diameter of one of the ports. 2. The diameter of either one of the first and second ports opened and closed by the land portion of the spool is set to about 1.5 times as the upper limit with respect to the length of the land portion of the spool. The spool valve according to claim 1.