JPS6137511B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling the valve position of a three-position switching valve for fluid control in food and other piping systems.

In general, a three-position switching valve includes three flow paths that communicate with each other, a second flow path and a third flow path are connected to the first flow path in an F-shaped branch shape, and the first flow path An on-off valve mechanism is provided between the first flow path and the second flow path, and between the first flow path and the second flow path, and only one of the on-off valve mechanisms is opened while the other one is opened. The above three channels are configured to be in three different communication states by closing them or by opening both on-off valve mechanisms and setting the opening degree to a desired value. .

Such three-position switching valves are widely used in fields where flow path switching efficiency affects work efficiency, such as in piping systems for filling foods such as beer and youth. In order to change the position of the valve body in the three-position switching valve, a control device thereof is attached coaxially to the three-position switching valve.

For conventional control devices, for example,
- As seen in Publication No. 46327, a piston integrally connected to the valve body is always resiliently biased in a certain direction, and the valve position when no control pressure is supplied is set at its upper or lower limit. In addition, the control pressure chamber of the cylinder containing the piston is divided into two parts, and a stopper member for setting the intermediate level of the valve body is provided in one of the halves.
A system was adopted in which the internal pressure of the control pressure chamber and the biasing force of the piston were balanced.

However, in such a control device, the biasing direction of the piston connected to the valve body is set to a constant value and cannot be changed.
It is not possible to change the valve position on the safe side when control pressure is not supplied. In other words, if the safety side of the valve body is set to normally open (opening the first flow path) during manufacture, it should be set to normally closed (the first flow path is blocked) after installation into the piping. It is impossible to change it, and in this case, it is necessary to replace it with a control device that is previously set to normally closed. Therefore, with conventional control devices, it is not possible to quickly change the control system in response to requests, and large-scale modifications to the piping system are required, and improvements have been desired. In order to improve this, if we try to improve the conventional system and satisfy the above requirements, the height of the control device will increase, which will significantly reduce its operability when attached to a collective pipe. , which is practically impossible because it requires an increase in installation space. Another disadvantage is that changing the position of the valve body, ie, changing the level of the stopper member, requires a great deal of effort during operation.

This invention improves the drawbacks of conventional control devices, and
The valve body position on the safe side can be easily set to the desired position by simply changing the intervening location of the spring that biases the piston connected to the valve body, and is compact. The purpose of this invention is to provide a control device that requires no effort to operate.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a control device 1 is a three-position switching valve 2.
It is coaxially attached to the top of the The three-position switching valve 2 has three flow paths 3a, 3b, and 3c configured in a substantially F shape.
and two valve mechanisms 4, 5, the valve mechanisms 4, 5
It is alternatively set to a normal state in which one of them is closed and the other opened, and a state in which both are opened at a certain degree of opening. In addition, 4
a and 5a are valve bodies, and 4b and 5b are valve seats.

Next, the control device 1 has a piston 6 housed in a cylinder 7 connected to the top of the three-position switching valve 2, and has a control section 8 in the top of the cylinder 7.

In FIG. 2, the piston 6 has recesses 9a and 9b on its upper and lower surfaces, respectively;
A connecting rod 10 connecting the piston 6 and the valve bodies 4a, 5a is fixed to the center thereof. Further, a first pressure chamber 11a and a second pressure chamber 11a in the cylinder 7 defined by the piston 6 are also provided.
Supply and exhaust pressure ports A and B are provided on each outer wall of the pressure chamber 11b (see FIG. 1). piston 6
An elastic member 12 such as a spring for biasing the forward movement direction (upward) or backward movement direction (downward) is selectively interposed in the first pressure chamber 11a and the second pressure chamber 11b. In this case, if a compression coil spring is used as the elastic member 12 and installed in the second pressure chamber 11b as shown in the illustrated example, the piston 6 or the valve bodies 4a, 5a are always biased in the forward direction. Therefore, as shown by the solid line in FIG. 1, the upper valve mechanism 4 is closed and the lower valve mechanism 5 is opened, and the first flow path 3a and the third flow path 3c are communicated with each other, resulting in a so-called normally open state. becomes. On the other hand, when the elastic member 12 is interposed in the first pressure chamber 11a, its bias closes the lower valve mechanism 5 and closes the upper valve mechanism, as shown by the imaginary line in FIG. 4 is opened, and the second flow path 3b and the third flow path 3c are communicated with each other, resulting in a so-called normally closed state. Which of the above two states to set is determined depending on which side is on the safe side. Note that when installing the elastic member 12, the recessed portions 9a and 9b of the piston 6 are useful for positioning the end of the coil spring.

Next, the control section 8 includes a predetermined mechanism built inside the control valve box 13. That is, the valve box 13
A partition wall 14 is provided in the middle of the cylindrical wall 13a, and the partition wall 14 defines a first chamber 15 and a second chamber 16. A threaded portion 17 is provided on a part of the inner wall surface of the first chamber 15.
A cylindrical positioning member 1 screwed into and out of the
A valve seat 19 is formed at the center of the lower end of the valve 8 . Also,
A rotating member 20 that also serves as a lid is rotatably provided at the upper end of the cylindrical wall 13a, and a plurality of pins 21 projecting downward from the inner surface of the rotating member 20 are provided.
The positioning member 18 is slidably fitted into vertical holes 22 formed at a plurality of locations. Therefore, by holding the handle 23 provided on the outer periphery of the rotating member 20 by hand and rotating the rotating member 20 by a predetermined angle in the forward or reverse direction, the positioning member 18 can be moved in the forward or reverse direction. It is rotated and displaced up and down. A bracket 24 is provided protruding from the cylindrical wall 13a near the rotating member 20, and a stopper screw 25 is provided on the bracket 24.

Further, a control rod 26 inserted through the first chamber 15 and the second chamber 16 connects a lower rod 26a connected to the piston 6 and an upper rod 26b passing through the rotating member 20 to the valve box. It is connected internally, and in this connection part, the valve body 1
A through hole 27 is formed that communicates the first chamber 15 and second chamber 16 of No. 3 with each other. And the first chamber 15
In the above, a cylindrical movable valve member 28 is fitted onto the upper rod 26b so as to be slidable in a hermetically sealed manner. A first valve portion 28a and a second valve portion 28b corresponding to the valve seat 19 of the positioning member 18 are provided, while a stepped portion 29a is formed directly below the first chamber side port 27a in the upper rod 26b. At the same time, this stepped portion 29
A spring 29b that constantly presses the movable valve member 28 against the movable valve member 28 is interposed between the movable valve member 28 and the movable valve member 20. These stepped portions 29
a and the spring 29b constitute a positioning mechanism 29 for the movable valve member 28, and the second
When the valve portion 28b is not in contact with the valve seat 19 of the positioning member 18, the first chamber side port 27a is closed by the first valve portion 28a of the movable valve member 28 due to the action of the positioning mechanism 29. is set to

Here, the first chamber 15 is divided into an upper compartment 15a and a lower compartment 15b by the valve seat 19 of the positioning member 18, and each compartment 15a, 15
Supply and exhaust pressure ports C and D are respectively provided at predetermined portions of the cylindrical wall 13a corresponding to the second
A supply/exhaust pressure port E is also provided at a predetermined portion of the cylindrical wall 13a corresponding to the chamber 16.

According to the control device 1 described above, the positions of the valve bodies 4a, 4b of the three-position switching valve 2 can be adjusted to the upper limit (the upper valve mechanism 4 is closed), the lower limit (the lower valve mechanism 5 is closed), and the lower limit (the lower valve mechanism 5 is closed). It can be easily set to an intermediate position, and can also be easily set to each of the above-mentioned normally open and normally closed states.

That is, the normally open state is set by interposing the elastic member 12 made of a compression coil spring in the second pressure chamber 11b of the cylinder 7, while the elastic member 12 is inserted into the first pressure chamber 11b of the cylinder 7.
By interposing it in the pressure chamber 11a, a normally closed state is set. Therefore, in this control device, when changing between the two states, there is no need to use separate control devices that are previously set to normally open or normally closed, as in the conventional case. Moreover,
There is no need for major rework of the piping system.

Further, when setting the valve bodies 4a, 4b to intermediate positions and making the three flow paths 3a, 3b, 3c communicate with each other, the following procedure is followed.

As shown in FIG. 7, when the normally open state is set, the supply and exhaust pressure ports D and A are connected through the piping 31, and in this state, the valve bodies 4a, 4
In order to obtain the desired position b, that is, the valve opening degrees of the upper valve mechanism 4 and lower valve mechanism 5, the rotating member 20 is rotated by a certain angle in the forward or reverse direction by operating the handle 23. As a result, the positioning member 18 is displaced to a position corresponding to the opening degree, for example, as shown by arrow P in FIG.
As a result, the second valve portion 28b of the movable valve member 28
A passage A is formed between the valve seat 19 of the positioning member 18 and the valve seat 19 of the positioning member 18.

When pressure is supplied to the supply and exhaust pressure port C from this state, the fluid pressure passes through the upper compartment 15a, the passage A, the lower compartment 15b, the supply and exhaust pressure port D, the piping 31, and the supply and exhaust pressure port A in this order. 1 enters the pressure chamber 11a, the piston 6 and the valve bodies 4a, 5a are pushed down against the bias of the elastic member 12, thereby opening the upper valve mechanism 4. As the piston 6 and the valve bodies 4a, 5a descend, the control rod 26 descends, and the movable valve member 28 follows this descent as indicated by the arrow Q in FIG.
When the second valve portion 28b of the movable valve member 28 comes into contact with the valve seat 19 of the positioning member 18, as shown in the figure, the upper compartment 15a and the lower compartment 15b are cut off, and the first pressure chamber 11a Pressure supply to is stopped. Therefore, the piston 6 and the valve bodies 4a, 5a
stops descending, they are held at their intermediate positions, and the three channels 3a, 3b, 3c are communicated with each other. Note that if excessive pressure acts on the first pressure chamber 11a at the time when the second valve portion 28b and the valve seat 19 come into contact, the control rod 26 becomes elastic as shown by arrow R in FIG. It descends against the bias of the member 12, but at this time, since the movable valve member 28 is positioned by the positioning member 18, the first chamber side port 27a of the through hole 27 opens to the lower compartment chamber 15b. As a result, the surplus pressure in the first pressure chamber 11a is transferred to the supply/discharge pressure port A and the piping 3.
1. Reverse flow through the supply and exhaust pressure port D and the lower compartment 15b, and further, the first chamber side port 27a, the through hole 2
7. It passes through the second chamber side port 27b, the second chamber 16, and the supply/exhaust pressure port E in this order and is released into the atmosphere. When the excess pressure is released in this way, the elastic member 1
2, the valve bodies 4a, 5a are set at proper positions (see FIG. 5).

On the other hand, as shown in Fig. 8, when the setting is normally closed, the supply and exhaust pressure port D
and supply/exhaust pressure port B are connected by piping 32,
Pressure is supplied to the supply/discharge pressure port E. In this case, initially, the first chamber side port 27a of the through hole 27 is
For example, as shown in FIG. 6, the second pressure chamber 11 of the cylinder 7 is open to the lower compartment chamber 15b.
Pressure is sent from the first chamber 15 to b through the piping 32, and this pressure causes the piston 6 and the valve body 4 to
When a and 5a are raised, the first chamber side port 27a of the through hole 27 is closed by the first valve portion 28a of the movable valve member 28, as shown in FIG. Pressure feeding to the second pressure chamber 11b is stopped,
The valve bodies 4a, 5a are set at predetermined positions, and the flow paths 3a, 3b, 3c are communicated with each other. Furthermore, when excess pressure is supplied to the second pressure chamber 11b, the control rod 26 is pushed up by an amount commensurate with the excess pressure.
For example, a passage A as shown in FIG. 2 is formed, and through this passage
released into the atmosphere. Therefore, the valve body 4
a and 5a are set at appropriate positions.

When the control method as explained above is adopted, the valve bodies 4a, 5a can only take the upper, lower, and intermediate positions, and the valve bodies 4a, 5a can only be held at the upper, lower, and intermediate positions, except when the handle 23 is operated. It is not possible to set the upper or lower limit from an intermediate position.
In other words, from the state in which the flow paths 3a, 3b, and 3c are communicating with each other, the second flow path 3b and the third flow path
It is impossible to switch to a state in which only the channels 3c communicate with each other, or to switch to a state in which only the first channel 3a and the third channel 3c communicate with each other.

Therefore, in order to meet the above request, we
A control valve 40 shown in FIG. 4 is attached.

In FIG. 2, the control valve 40 has a valve box 41 whose interior is divided into a first chamber 43 and a second chamber 44 by a partition plate 42. The first piston 45 and the second piston 46 are installed separately, and the pressure receiving surfaces 45a and 46 of each of these pistons 45 and 46 are
A pair of supply and exhaust pressure ports F, G,
H and I are provided. Further, the second piston 46 has a penetrating valve hole 49 formed at its axial center position, and a first valve seat portion 50 is formed at an opening on the back side of the valve hole 49 and an opening on the pressure receiving surface 46a side, respectively.
a and a second valve seat portion 50b, and a shaft portion 45b integrally formed with the first piston 45.
protrudes into the second chamber 44, and a first valve body 51a corresponding to the first valve seat 50a is provided at the tip thereof, and a second valve seat 5 is provided in the valve hole 49.
A second valve body 51b corresponding to 0b is provided.

Here, springs 52, 53 are interposed between the first piston 45, the second piston 46, and the partition plate 42, so that both the pistons 45, 46
are urged in opposite directions, so that the first valve seat portion 50a and the first valve body 51a are open in their natural state. Further, a spring 54 is interposed between the second piston 46 and the second valve body 51b, and the second valve body 51b is biased in the closing direction. In that case, in the natural state, the tip end surface of the second valve body 51b hits the outer wall of the valve box 41, and despite the above-mentioned bias, the second valve seat 50b and the second valve body 51b
The relationship between the two is open. Furthermore, the shaft portion 45b of the first piston 45 has a
A communication hole 55 is formed in the second piston 46 to communicate between the pressure receiving surface 45a of the piston 5 and the second chamber 44, and a communication hole 56 is formed in the second piston 46 to extend between the outer peripheral surface thereof and the first valve seat 50a. The second valve body 51b also has a communication hole 57 that communicates the two compartments in the valve hole 49 divided by the second valve body 51b.
is formed. A supply/discharge pressure port J corresponding to the communication hole 56 is provided on the outer wall of the valve box 41.

In addition, in FIG. 2, 58 is a switching valve, 59 is a pressure sending compressor, and 60 is a blind lid.

In order to cause the control valve 40 to perform the above-mentioned action, as shown in FIG. G.
D and J and A and I are connected, respectively, while supply and exhaust pressure ports F and H are connected to the switching valve 58 by pipes 64 and 65.

In this state, when the switching valve 58 is set at the neutral position, as is clear from FIG.
Because the supply and exhaust pressure ports F and I in the control valve 40 are in communication with each other through the communication hole 55, the valve hole 49, and the communication hole 57, the first pressure chamber 11a of the cylinder 7 is opened to the atmosphere, and the valve body 4a, 5a is set to its upper limit by the bias of the elastic member 12, and the upper valve mechanism 4 is closed. Therefore, only the first flow path 3a and the third flow path 3c are communicated with each other.

Next, when setting the valve bodies 4a, 5a to a desired intermediate position, after displacing the positioning member 18 to a predetermined level as described above, the switching valve 58 is moved to the first position.
Set to position P ₁ . As a result, supply and exhaust pressure port F
The fluid pressure sent from the first piston 45 acts on the pressure receiving surface 45a of the first piston 45, and
Move it downward as indicated by arrow S in the figure. Therefore, the first valve body 51a closes the first valve seat portion 50a, and the fluid pressure enters the supply and exhaust pressure port C through the supply and exhaust pressure port G and the piping 61. On the other hand, the supply and exhaust pressure ports J and I are communicated through the communication hole 56, the valve hole 49, and the communication hole 57, so the supply and exhaust pressure ports D and H
are communicated. Therefore, in the same manner as described above, the valve bodies 4a, 5a are set at predetermined intermediate positions, and the flow paths 3a, 3b, 3c are communicated with each other.

If it becomes necessary to close the lower valve mechanism 5 from this state, the switching valve 58 is set to the second position _P2 and pressure is sent to the supply and exhaust pressure port H. As a result, as shown in FIG. 4, the fluid pressure sent from the supply/discharge pressure port F acts on the pressure receiving surface 46a of the second piston 46, causing the second piston 46 to move in the direction indicated by the arrow T in FIG. Move it up. Therefore, the second valve seat portion 50b and the second valve body 51b are pressed together to close them, and fluid pressure is directly supplied to the first pressure chamber 11a of the cylinder 7 through the supply/discharge pressure port I and the piping 63. The valve bodies 4a, 5a are moved to their lower limits against the bias of the elastic member 12, and the lower valve mechanism 5 is closed.

On the other hand, when the control device 1 is set to normally closed, the piping 6
6, 67, 68 for supply and exhaust pressure ports E, G, and D.
Connect J, B and I respectively. Since the operation in this case is clear from the above, the details will be omitted.

As is clear from the above description, according to the present invention, the installation location of the elastic member that biases the piston connected to the valve body in the forward or backward direction is located in the first pressure chamber and the second pressure chamber of the cylinder. Since the normally open and normally closed states can be easily set by simply changing between the Not only does piping work become unnecessary, but the entire device is made more compact and the cost is reduced.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of a three-position switching valve to which a control device according to an embodiment of the present invention is attached;
The figure is a partially cutaway side view of the control device with the control valve attached, Figures 3 and 4 are longitudinal side views for explaining the operation of the control valve, and Figures 5 and 6 are the operation of the control device. FIG. 7 is a piping system diagram when normally open, and FIGS. 8 and 9 are piping system diagrams when normally closed. 1...Control device, 2...Three-position switching valve, 3a, 3
b, 3c...flow path, 4, 5...valve mechanism, 4a, 5a...
Valve body, 6... Piston, 7... Cylinder, 10... Connection rod, 11a... First pressure chamber, 11b... Second pressure chamber, 12... Elastic member, 13... Control valve box, 13a
...Cylindrical wall, 15...First chamber, 16...Second chamber, 18...
Positioning member, 20... Rotating member, 23... Handle, 26... Control rod, 27... Through hole, 27a...
First chamber side port, 27b...Second chamber side port, 28
...Movable valve member, 28a...First valve part, 28b...Second
Valve part, 29...positioning mechanism, A, B, C, D, E
...Supply/exhaust pressure port.

Claims (1)

[Claims] 1. In a three-position switching valve configured so that three flow paths are set to three different communication states by switching the valve body between the upper and lower limits and three positions in between, the valve body is connected to the valve body. A supply and exhaust pressure port is provided on each outer wall of a first pressure chamber and a second pressure chamber defined by the piston of the cylinder containing the piston, and the piston is biased in the forward or backward direction. An elastic member can be selectively inserted into the first pressure chamber and the second pressure chamber, and the first chamber of the control valve box is partitioned into different first and second chambers. A positioning member for setting an intermediate position of the valve body is disposed movably, and a control rod inserted through the first and second chambers of the valve body is connected to the valve body. A through hole is formed to communicate the first chamber and the second chamber of the valve box with each other, and a movable valve member is externally fitted in the first chamber so as to be slidable in the axial direction. A first valve part for opening and closing the first chamber side port and a second valve part corresponding to the valve seat formed on the positioning member are provided, and only when the second valve part is not in contact with the valve seat. A positioning mechanism is provided inside the valve box for positioning the movable valve member relative to the control rod so that the first chamber side exhaust port is closed by the first valve portion of the movable valve member, and The outer walls of the two compartments partitioned by the valve seat and the second
A control device for a three-position switching valve, characterized in that supply and exhaust ports are provided on each of the outer walls of the chamber.