JPH039583Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a directional control valve that switches and controls the flow direction of fluid.

Conventionally, this type of directional control valve was
As shown in the publication, by axially operating the valve body which is slidably inserted into the sliding hole of the valve body, an annular groove is formed on both sides of the annular groove provided by recessing the inner surface of the sliding hole. A valve portion provided in the shape of an annular projection on the outer surface of the valve seat and the valve body is provided so that the load path can be switched and communicated with an inlet path and a discharge path by being detached from the valve seat. However, since the valve element is supported in the sliding hole by the sliding part provided on one side of the valve element, the valve element slides due to the biasing force that acts on the valve element due to the fluid flow between each passage. The valve part tends to tilt with respect to the axis of the moving hole, making it difficult to obtain a good seating condition as the valve part hits the valve seat unevenly, and the flow direction of the fluid cannot be controlled well.

The present invention aims to eliminate such drawbacks, and provides a directional control valve that is not easily affected by biasing force acting on the valve body and can provide good switching control.

Therefore, in the present invention, the introduction path of the sliding hole which communicates the introduction path for introducing the pressure fluid, the load path connecting to the fluid actuator side, and the discharge path connecting to the low pressure side with an interval in the axial direction is open. An annular groove is provided near the inner surface of the annular groove to open the load path on the bottom surface, and both ridges intersecting with the sliding holes on both sides of the annular groove are formed into valve seats of the same diameter. , an annular switching groove communicating with the inlet passage is provided on one side of the valve part, which is located in the annular groove and has an annular projection shape with a diameter larger than the valve seat, and an annular switching groove communicating with the discharge passage on the other side. and a valve body provided with sliding parts at both ends that slidably fit into the sliding hole, and the valve part switches and communicates the load path between the introduction path and the discharge path by axial movement of the valve body. The diameter is gradually expanded from both switching grooves toward the annular groove side, and the diameter is expanded so that communication between each path is interrupted or minimized during the switching transition period when the load path is switched to communicate with the inlet path and the discharge path. A control surface is formed at the tip to form a minute gap between the bottom surface of the annular groove and the bottom surface of the sliding or annular groove.

In the structure of the present invention, since the sliding portions provided at both ends of the valve body provide support for the sliding hole of the valve body, the biasing force acting on the valve body due to the fluid flow between each path is The valve body can be made less likely to tilt with respect to the axis of the sliding hole, and the direction of fluid flow can be switched and controlled favorably.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In Fig. 1, reference numeral 1 denotes a valve body, in which a cylindrical sleeve 3 is fitted into a hole 2 of different diameters drilled from one side to form a sliding hole 4, and an introduction path P through which pressure fluid is introduced. A load path A connected to the fluid actuator side and a discharge path R connected to the low pressure side are opened and communicated with the inner surface of the sliding hole 4 at intervals in the axial direction. Valve body 1
An annular groove 5 is provided by recessing the inner surface between the introduction path P and the discharge path R of the sliding hole 4 and opening the load path A at the bottom, and intersects with the sliding hole 4 on both sides of the annular groove 5. Valve seats 6 and 7 having the same diameter are formed on both edges. Reference numeral 8 denotes a valve body, which has a through hole 9 penetrated therein so as to pressure-balance the acting force of the fluid acting on both ends, and has a diameter larger than the valve seats 6 and 7 so as to be located in the annular groove 5 on the outer surface at approximately the center. A valve part 13 in the form of an annular protrusion is provided in the valve part 13, and an annular switching groove 11 communicating with the inlet passage P is formed on one side of the valve part 13, and an annular switching groove 12 communicating with the discharge passage R is formed on the other side by recessing the outer surface. At the same time, sliding portions 23 and 24 are provided at both ends to slidably fit into the sliding hole 4. The valve portion 13 of the valve body 8 has both side surfaces seated on the valve seats 6 and 7 connected to each other through the switching grooves 11 and 12, and is formed in a shape whose diameter gradually increases toward the annular groove 5 side, and a load path A is introduced. The enlarged diameter tip slides on the bottom surface of the annular groove 5 so as to interrupt the communication between the passages P, A, and R and regulate the fluid flow during the switching transition period when the passage P and the discharge passage R are switched to communicate with each other. A control surface 14 is formed. 10 is a communication hole provided in the valve body 8 to communicate the switching groove 12 with the through hole 9; 15 is an electromagnetic device fixed to one side of the valve body 1 so as to close the opening of the slide hole 4; The movable iron core 17 is attracted to the fixed iron core 18 by energization, and the suction force is obtained via the operating member 19. Reference numeral 20 denotes a return spring provided in the sliding hole 4 so as to counteract the attraction force of the electromagnetic device 15 and apply an acting force to the valve body 8; The piston 22 is a spring interposed between the valve body 8 and the piston 21, and the spring constant is set to be larger than that of the return spring 20, but the action during installation is The force is set to be weaker than the acting force of the return spring 20.

Next, the operation of this configuration will be explained.

FIG. 1 shows a non-energized state of the electromagnetic device 15,
The valve body 8 is located at the upper moving end where the valve portion 13 is seated on the valve seat 7 due to the action of the return spring 20, and blocks the introduction path P, and connects the load path A to the annular groove 5 and the switching groove 1.
2. Communicates with the low pressure side via the discharge path R. Now, when the electromagnetic device 15 is energized, the attractive force acting on the movable iron core 17 is applied to the operating member 19 and the piston 2.
1. The force applied to the valve body 8 via the spring 22 is applied to the return spring 2 due to the difference in spring constant.
When the differential force becomes stronger than 0, the valve body 8 moves to the sliding part 23.
and 24 slide through the sliding hole 4, and the valve part 13 becomes the valve seat 7.
After a switching transition period in which the control surface 14 of the valve part 13 closes the opening of the load path A and cuts off communication between the paths P, A, and R, the valve part 13 seats on the valve seat 6. It is operated to the end, shutting off the discharge path R, switching the load path A into communication with the introduction path P, and introducing the fluid actuator pressure fluid. Also, from this state, the electromagnetic device 1
5 is de-energized, the acting force of the spring 22 with a large spring constant suddenly weakens, and the valve body 8 returns to its original position after a switching transition period due to the acting force of the return spring 20, thereby opening the inlet path P. The load path A is switched to connect with the discharge path R, and the fluid in the fluid actuator is discharged to the low pressure side.

With this axial movement of the valve body 8, the sliding portions 23 and 24 provided at both ends of the valve body 8 provide support for the sliding hole 4 of the valve body 8, so that there is a gap between each path P, A, and R. Due to the fluid flow, the biasing force acting on the valve body 8 makes it difficult for the valve body 8 to tilt with respect to the axis of the sliding hole 4, and the valve part 13 can be seated well on the valve seats 6 and 7, thereby preventing the fluid from flowing. The flow direction can be switched and controlled well. Moreover, since the valve body 8 is difficult to incline with respect to the axis of the sliding hole 4, the sliding parts 23 and 24 do not forcefully slide on the inner surface of the sliding hole 4, and the sliding resistance of the valve body 8 can be reduced. axial operation can be obtained.

Also, during the switching transition period when the discharge passage R is shut off and the load passage A is switched to communicate with the introduction passage P, the sliding portion of the control surface 14 of the valve portion 13 with the bottom surface of the annular groove 5 is used to connect the passages P, A, and R. Since the communication is blocked and the fluid flow is regulated, it is possible to effectively prevent the pressure drop in the introduction path P due to the pressure fluid in the introduction path P flowing to the discharge path R during the switching transition period. The starting response of the fluid actuator can be improved when the load path A is switched to communicate with the introduction path P from a state where the load path A is disconnected and communicated with the discharge path R.

FIG. 2 shows another embodiment, and to describe the differences from the first embodiment, a plug member 27 having a bottomed hole inside is inserted into a different diameter hole 26 penetrating the valve body 25. A sliding hole 28 is formed by fitting the main body 25 so as to close the opening from the side surface opposite to the side surface on which the electromagnetic device (not shown) is fixed. A control surface is formed that forms a minute gap between the control surface and the bottom surface of the groove to obtain the same effect as in the first embodiment.

FIG. 3 shows still another embodiment, and to describe the differences from the first embodiment, the valve body is divided into two parts 31 and 32 at the position of the annular groove 30 of the sliding hole 29. In addition to fixing and forming,
A control surface that forms a minute gap between the enlarged diameter tip of the valve portion of the valve body and the bottom surface of the annular groove is formed to obtain the same effect as in the first embodiment.

FIGS. 4 and 5 show yet another embodiment, and to describe the differences from the first embodiment, FIG. An opening communicates with the inner surface of the hole 4,
In FIG. 5, the discharge passage R2 is opened and communicated with the bottom surface of the sliding hole 4.

In this way, the present invention has an introduction path of sliding holes that are spaced apart in the axial direction and communicate with each other through the introduction path for introducing pressure fluid, the load path that connects to the fluid actuator side, and the discharge path that connects to the low pressure side. The valve body has an annular groove that opens the load path at the bottom by recessing the inner surface near the opening inner surface, and the valve seat has the same diameter at both ridges that intersect with the sliding holes on both sides of the annular groove. and an annular switching groove communicating with the inlet passage on one side of the valve part which is located in the annular groove and provided in the shape of an annular projection with a diameter larger than the valve seat, and an annular switching groove communicating with the discharge passage on the other side. The valve body is provided with sliding parts at both ends that are slidably fitted into the sliding holes, and the valve part switches and communicates the load path between the inlet path and the discharge path by operating the valve body in the axial direction. The diameter is expanded sequentially from both switching grooves toward the annular groove side so that the flow of the flow increases, and the diameter is expanded so as to cut off or minimize communication between each path during the switching transition period when the load path is switched to communicate with the inlet path and the discharge path. By forming a control surface that forms a minute gap between the bottom surface of the annular groove and the bottom surface of the sliding or annular groove at the tip of the annular groove, the valve is activated by the biasing force that acts on the valve body due to the fluid flow between each path. The body can be made less likely to tilt with respect to the axis of the sliding hole, and the direction of fluid flow can be switched and controlled favorably.

In addition, the valve portion of the valve body has an enlarged diameter tip that slides or slides against the bottom of the annular groove so as to cut off or minimize communication between each path during the switching transition period when the load path is switched to the inlet path and the discharge path. Since the control surface forms a small gap between the bottom surface of the annular groove and the bottom surface of the annular groove, it is possible to switch the load path between the introduction path and the discharge path without reducing the amount of communication between each path. During the switching transition period, the pressure fluid in the inlet passage becomes difficult to flow to the discharge passage, effectively preventing the pressure drop in the inlet passage, and switching the load passage to the inlet passage from the state in which the inlet passage is shut off and the load passage communicates with the discharge passage. When communicating, the starting response of the fluid actuator can be improved.

Furthermore, since the valve body is less likely to tilt with respect to the axis of the sliding hole, the sliding resistance of the valve body can be reduced and good axial operation can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a directional control valve showing one embodiment of the present invention, and FIGS. 2 to 5 are partial sectional views showing other embodiments. 1, 25... Valve body, 4, 28, 29... Sliding hole, 5, 30... Annular groove, 6, 7... Valve seat, 8...
... Valve body, 11, 12 ... Switching groove, 13 ... Valve part,
23, 24...Sliding part, P...Introduction path, A...Load path, R, R1, R2...Discharge path.

Claims (1)

[Scope of utility model registration request] The inner surface is recessed near the inner surface where the introduction path of the sliding hole in which the introduction path for introducing the pressure fluid, the load path connecting to the fluid actuator side, and the discharge path connecting to the low pressure side are opened and communicated with each other at intervals in the axial direction. The valve body has an annular groove that opens the load path on the bottom surface, and the valve body has valve seats with the same diameter at both ridges that intersect with the sliding holes on both sides of the annular groove. An annular switching groove that communicates with the inlet passage is provided on one side of the valve part, which has a larger diameter than the valve seat and has an annular projection shape, and an annular switching groove that communicates with the discharge passage on the other side, so that the valve part can slide into the sliding hole. It is equipped with a valve body with sliding parts on both ends that can be freely fitted,
The valve part is formed so that the diameter thereof gradually increases from both switching grooves to the annular groove side so that the load passage can be switched between the introduction passage and the discharge passage by the axial movement of the valve body, and the load passage can be connected to the introduction passage and the discharge passage. A control surface that forms a minute gap between the bottom surface of the annular groove and the bottom surface of the sliding or annular groove is formed on the enlarged diameter tip to cut off or minimize the communication between each path during the switching transition period when switching to and communicating with each other. A directional valve made of