JPS62270877A - Diaphragm type pilot operated directional control valve - Google Patents

Abstract

PURPOSE:To aim at miniaturization in a valve, by setting up three passages, being interconnected to each port for feed, outflow and drainage and opened to a control block side end face, concentrically, and making an interval between adjacent two passages possible to be opened or closed with a center valve part of a diaphragm and a peripheral annular valve part. CONSTITUTION:Each of ports 41-43 for feed, load and drainage is formed in three sides of a passage block 40, while an annular part 46 is formed in the circumference of a center hole 44 of the passage block 40, and this annular part 46 is interconnected to the feed port 41. And, each of annular passages 47 and 48 at both load and drainage sides is formed at the side of a control block 60 of the passage block 40 concentrically with a partition wall 45, and these passages 47 and 48 are interconnected to these ports 42 and 43 respectively via interconnecting passages 49 and 50. And, a diaphragm 70, where a central thick-wall part is formed in a center valve part 73 and an annular part between annular beads 71 and 72 in an annular valve part 74 respectively, is interposed between both these blocks 40 and 60, and each of these valve parts 73 and 74 is controlled by feed control over compressed oil to pilot pressure passages 63 and 64.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention "Technical Field" The present invention is directed to a directional control valve that directly opens and closes a flow path using a pilot pressure applied to a diaphragm to change the direction of fluid flow.

"Prior art and its problems" The basic structure of this type of directional control valve is disclosed in U.S. Patent No. 4.5.
No. 16,605 proposes. FIGS. 5 to 9 show an example of this, and the principle of operation of this directional control valve will first be explained based on these figures.

This directional control valve has a diaphragm 1 that also serves as a gasket.
The flow path block 20 has a flow path block 20 and a control block 10 that are separated by a pressure fluid source P. The load port 25 and discharge port 27 of are open.

A pair of separation passages 23 separated from the supply port 22 are
Each of them communicates with a pair of IM-shaped passages 24 . jI load port 25 opens at the center of this annular passage 24, and a discharge port 27 opens at the center of an annular passage 26 communicating with this load port 25. and these annular passages 24
, load port 25, annular passage 26 and discharge port 27
are each opened at the end face on the control block 10 side and are opposed to the diaphragm 11. Further, the load port 25 is connected to the actuator A, and the discharge port 27 is open to the atmosphere.

The illustrated actuator A is a cylinder device, and the piston P
The load ports 25 of the left and right flow path switching valve sections 21 communicate with the cylinder chambers S1 and S2, which are partitioned by the cylinder chambers S1 and S2, respectively.

The load port 25 and the discharge port 27 are secured by a valve seat 25s and a valve seat 27s, respectively, which are brought into contact with and separated from a diaphragm. ] 2 is a grid (mesh body) that prevents the diaphragm 11 from being deformed into the load port 25 (discharge port 27) due to the pressure difference between the front and back sides of the diaphragm 11.

The control block 10 has a pilot pressure passage 31.3 opposite the center of the load port 25 and exhaust port 27.
2 are open. The diaphragm 11 deforms toward the flow path block 20 when a pilot pressure p equal to or higher than a certain pressure is applied to the pilot pressure passages 31 and 32 by the pilot pressure control device 133. Therefore, when the pilot pressure p is applied to the pilot pressure passage 31, the communication between the supply port 22 and the load port 25 is cut off, and on the other hand, when the pilot pressure p is applied to the pilot pressure passage 32, the communication between the supply port 22 and the load port 25 is cut off. Communication with the discharge port 27 is cut off. Therefore, by controlling the supply of pilot pressure p to the pilot pressure passages 31 and 32 by the pilot pressure control device 33, the supply of fluid to the actuator A can be controlled as shown in FIGS. 5 to 8.

That is, in FIGS. 5 to 8, the pilot pressure passages 31 or 32 marked with p are applied with pilot pressure p, and the passages not marked are open to the atmosphere. As is clear from the open and closed states of the flow passages shown in these figures, the piston P moves to the right in the state of Fig. 5, moves to the left in the state of Fig. M6, and moves to the left in the state of Fig. 7 and 8.
In the state shown in the figure, it stops. In the state shown in Fig. 7, pressurized fluid is supplied to the cylinder chambers S1 and S2+, so even if force is applied to the piston P, it does not move, but in the state shown in Fig. 8, both cylinders 'M S I and S2 are connected to the discharge port. 27
Since it is in communication with the piston P, the piston P can be moved freely.

The directional control valve, which has the above-mentioned operating principles, has excellent features such as no sliding parts, therefore no lubrication, large flow capacity, no need for H4-tight machining, and good workability. There is. However, in this directional control valve, the dian ram 11 must be activated in two locations, one in the center of the round port 25 and the other in the center of the discharge port 27, for each set of supply port 22, load port 25, and discharge port 27. Therefore, there is a problem of increasing the size.

Object of the Invention In view of this problem, the object of the present invention is to obtain a diaphragm type pilot operated directional valve structure which can be further downsized.

"Summary of the Invention" The present invention has been made based on research on the number of passages of each port opened on the end face of the flow path block on the control proximal side. It was completed based on this perspective.

That is, the present invention concentrically arranges a supply port, a load port, and a discharge port (three passages that are connected to these ports and opens at the end face of the control block) formed in the flow path block, and It is characterized in that the two adjacent passages of the three passages are opened and closed by a central valve part of the diaphragm that individually applies pilot pressure, and an annular valve part on the periphery thereof.

"Embodiments of the Invention" The present invention will be described below with reference to illustrated embodiments. 1 to 4 show an embodiment of the present invention, in which a flow path block 40 is provided with a supply port 4 as the minimum unit of a flow path switching valve.
1, a load port 42, and a discharge port 43 are formed. Each of these ports is formed from three peripheral sides of the rectangular parallelepiped flow path block 4o toward the center, and among them, the load port 42 directly communicates with a center hole 44 formed at the center of the flow path block 4o. I'm here.

An annular portion (
A supply annular passageway 46 is formed, which communicates with the supply port 41. 1IFil
The end face of the wall 45 on the control block 60 side is the valve seat 45s! Form.

On the end face of the flow path block 4Q on the control block 60 side,
A load-side annular passage 47 and a discharge-side annular passage 48 are formed concentrically with the partition wall 45, respectively. This load-side annular passage 47 is connected to the load port 42 via a communication passage 49,
The discharge-side annular passages 48 communicate with the discharge ports 43 via passageways 50 (FIG. 2). Further, on the end surface of the flow path block 40 on the side of the control block 60, the annular portion 46 and the annular passage 47.48, and the annular passage 47.48.
on the outside of each annular bead 71 of the diaphragm 70
．． 72 is fitted into bead grooves 51 and 52 concentric with the valley grooves mentioned above.
is formed.

The diaphragm 70 has a central circular thick wall portion as the central valve portion 7.
3, and the annular part between the annular beads 71 and 72 is the annular valve part 74, and the central valve part 73 is the valve seat 45sIL:@
When the user is seated, communication between the supply port 41 and the load port 420 is cut off. Further, the annular valve portion 74 is connected to the load side annular passage 4.
7 and the discharge side annular passage 48, the communication between the load port 42 and the discharge port 43 is cut off.

The control block 60 is formed with a central recess 61 and an annular recess 62 concentric with the central valve portion 73 and the annular valve portion 74. Pilot pressure passages 63 and 64 communicate with each other. Only one pilot pressure passage 63 opens at the center of the central recess 61, and a plurality of pilot pressure passages 64 open around the annular recess 62. A pilot pressure control device 65 controls the supply of pilot pressure to the pilot pressure passages 63 and 64.

Therefore, in the main direction switching valve having the above configuration, when the pilot pressure p is applied to the pilot pressure passage 63, the central valve portion 73 of the diaphragm 70 seats on the valve seat 45S, cutting off communication between the supply port 4 and the load port 42. When the pilot pressure p is applied to the pilot pressure passage 64, the annular valve portion 74 comes into close contact with the load side annular passage 47 and the discharge side annular passage 48, cutting off communication between the load port 42 and the discharge port 43. Conversely, when the supply of the pilot pressure p to the pilot pressure passages 63, 64 is stopped, the supply port 41 and the load port 42, or the load port 42 and the discharge port 43 are brought into communication. Therefore, by controlling these pilot pressures p%, the pressure from the pressure fluid source P can be supplied to the load port 42, or the pressure fluid supplied to the load port 42 can be discharged to the discharge port 43. .

In the illustrated example, the load port 42 is connected to a single pressure chamber 81 of the actuator 80 . Therefore, when the load port 42 and the supply port 41 are brought into communication and at the same time the communication between the load port 42 and the discharge port 43 is cut off, the piston 82 is moved against the force of the compression spring 81, and conversely, the load port 42 and the supply port 41 disconnection 5 load port 42
When the piston 82 is brought into communication with the discharge port 43, the piston 82 can be returned to its original position by the force of the compression spring 83.

The directional control valve of the present invention has the advantage of being small in size.
There is an advantage that the flow rate, especially the flow rate between the load-side annular passage 47 and the discharge-side annular passage 48, can be increased. That is, a load-side layered passage 47 (discharge ft 111
1! The diameter D of the annular passage 48) is sufficiently larger than the diameter d of the partition wall 45, so that the annular valve portion 74 of the diaphragm 70 slightly closes to the annular passage 47 on the load side (the annular passage 48 on the discharge side).
), the larger the flow area is secured. Therefore, although it is small, it is possible to flow a large flow rate.

Note that the present invention does not care about the specific configuration of the pilot pressure control unit 65 for applying pilot pressure to the pilot pressure passage 63 or 64.

Although the above embodiment shows the present invention in its simplest form, one flow path block 40 has a common supply port 41 and a pair of load ports 42 and a pair of discharge ports 43. If installed, it is possible to obtain a directional switching valve that can move the piston to the right or left and also stop it, just like the directional switching valve described in FIGS. 4 to 8.

Generally speaking, in the above embodiments and claims, port 41.4
2.4318 are called a supply port, a load port, and a discharge port, respectively, but these expressions are for ease of understanding, and the point is that port 42 can be called port 41 or port 43. Alternatively, the present invention can be used as a valve that communicates at the same time.

"Effects of the Invention" As described above, the present invention concentrically connects three passages that communicate with each of the supply ports, load ports, and discharge ports formed in the flow path block and open to the end surface on the control block side. two adjacent passages of these three concentric passages.
Since the passages are opened and closed by the central valve part of the diaphragm, which individually applies pilot pressure, and the annular valve part on the periphery, the diaphragm-type piston-operated direction switching valve can be made smaller. . In other words, the flow path block and control block can be made smaller, the diaphragm can be made smaller and its shape simpler, and assembly and filling can be improved. A large flow path area can be ensured with a slight movement of the diaphragm, and a directional control valve that is small in size but capable of allowing a large flow rate to flow can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view showing an embodiment of the diaphragm type pilot operated directional control valve of the present invention, with the right half and left half in different opening states, and Fig. 2 and M3 are the same as those in Fig. 1. II
4 is a plan view of the diaphragm showing the alignment of the central recess, annular recess, and pilot pressure passage of the control block;
Figures 5 to 8 are cross-sectional views of the directional switching well to which the present invention is applied in different operating states, and Figure 9 is a cross-sectional view taken from IX-IX in Figure 5.
It is a cross-sectional view of the line. 40... Channel block, 41... Supply port, 42
...Load port, 43...Discharge port, 44...
Center hole, 45... Partition wall, 45s... Valve seat, 46...
- Annular part (supply side t'fi-shaped passage), 47... Load side annular passage, 48... Discharge side annular passage, 49.50...
・Communication path, 51.52... Beat groove, 60... Control block, 61... Central recess, 62... Annular recess,
63.64... Pilot pressure passage, 70... Diaphragm, 71.72... Annular beat, 73... Center valve section, 74... Annular valve section. Patent applicant: Fujikura Rubber Industries Co., Ltd. Procedural Amendment (October 2, 1986)

Claims (1)

[Claims] (1) A diaphragm is sandwiched between a flow path block and a control block, and the flow path block has a supply port that receives pressure fluid from a pressure fluid source, a load port connected to the actuator, and a discharge port that is open to the atmosphere. At the same time, passages communicating with the supply port, load port, and discharge port are opened on the control block side end surface of the flow path block, and on the other hand, on the control block side, the flow path block is formed on the diaphragm. A pilot pressure passage is formed to apply pilot pressure from the opposite surface, and the pilot pressure applied to the pilot pressure passage is controlled to directly open and close the passage between the load port and the supply port or the discharge port by the diaphragm. In the diaphragm type pilot-operated directional control valve, three passages are arranged concentrically and communicate with the supply port, load port, and discharge port, respectively, and open on the control block side end face of the flow path block. A diaphragm type pilot operating direction characterized in that two adjacent passages of the three concentric passages are opened and closed by a central valve part of the diaphragm that individually applies pilot pressure and an annular valve part on the periphery thereof. switching valve.