JP2002276832A - Directional control valve with preferential circuit, control device using directional control valve with preferential circuit and shutter opening/closing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a directional control valve with preferential circuit in which one flow passage of two flow passages is preferentially opened. SOLUTION: An introduction port 13 for a fluid, a first feeding port 14 and a second feeding port 15 are provided on a sleeve 11 and a spool 20 is fitted into a hollow part 12 penetrating in an axis direction. When a pilot fluid is fed to a first pilot port 18, the spool 20 is moved to one direction and the first flow passage I is opened by a communication of the introduction port 13 and the first feeding port 14. When the pilot fluid is fed to a second pilot port 19, the spool is moved to an opposite direction and a second flow passage II is opened by a communication of the introduction port 13 and the second feeding port 15. Since a pressure-receiving area of the second pilot port 19 is formed such that it becomes larger than that of the first pilot port 18, when the pilot fluid is simultaneously fed to both ports 18, 19. The second pilot port 19 is preferentially opened by a difference of the pressure-receiving areas and the second flow passage II is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching valve with a priority circuit, a control device controlled using the switching valve,
In particular, it relates to a shutter opening / closing device.

[0002]

2. Description of the Related Art FIGS. 3A and 3B show an example of a conventional pneumatic switching valve.

The switching valve (70) moves the spool (72) fitted in the sleeve (71) in the axial direction to move the spool (72) into the inlet (7).
The flow path of the fluid introduced from 3) is switched in two directions. That is, as shown in FIG. 3A, when pilot air is supplied to the first pilot port (74) on the left side of the drawing, the spool (72) moves to the right and the fluid inlet (73).
And the first outlet (75) on the left side communicate with the first outlet (75).
Is opened. As shown in FIG. 3 (B), when pilot air is supplied to the second pilot port (76) on the right side in the drawing, the spool (72) moves to the left and the inlet (73) and the second The second outlet (II) is opened by communicating with the outlet (77). In any state, the outlets (75) and (77) that are not in communication with the inlet (73) are open in communication with the outlets (78) and (79), respectively. When the pilot air is not supplied to any of the first and second pilot ports (74, 76), the position of the spool (72) immediately before is maintained.

FIG. 4 shows a shutter opening / closing device as an example of use of the above-mentioned switching valve (70).

The shutter opening / closing device (80) is provided in a box for transferring parts and the like, for example, in a transfer path of a transfer conveyor for packing. Otherwise, the shutter (81) is closed to prevent foreign matter from entering the inside of the apparatus. The shutter (81) is attached to a plunger (83) of a cylinder (82), and the opening and closing of the shutter (81) is performed by an up / down operation of the plunger (83) by switching a flow path of the switching valve (70). In FIG. 4, (30) is an air pump, and (31) is an air pump.
A working fluid supply pipe for supplying the compressed air generated in (30) as the working fluid of the cylinder (82) to the introduction port (73) of the switching valve (70), and (32) supplies the compressed air. A first pilot air line for supplying pilot air to the first pilot port (74) and a second pilot air line (33) for supplying the compressed air to the second pilot port (76) as pilot air.

The basic operation of opening and closing the shutter (81) is as follows. [1] The box (S) conveyed by the conveyor (90) is the front limit switch before the shutter (81)
When (91) is hit, pilot air is supplied to the second pilot port (76) of the switching valve (70) via the second pilot air line (33), and the spool ( 72) moves to the left, the inlet (73) communicates with the second outlet (77), and the second channel (II) is opened. The working fluid supply line (31)
The compressed air introduced into the switching valve (70) through the inlet (73) passes through the second flow path (II), and retreats the cylinder (82) through the retreat pipe (92). Side port (85)
The plunger (83) moves backward, that is, rises, and the shutter (81) is opened. [2] The box (S) is transported from the opened shutter (81) to the inside of the apparatus. When the box (S) passes through the shutter (81) and comes off the front limit switch (91),
The supply of pilot air to the second pilot port (76) is stopped, and the switching valve (70) maintains the state in which the spool (72) has moved to the left (FIG. 3B). In this state, the second flow path (II) is opened, and the compressed air is still supplied to the retreat pipe (92), and the open state of the shutter (81) is maintained. [3] The box (S) conveyed inside is a shutter (8
2) When the rear limit switch (93) at the rear is hit, pilot air is supplied to the first pilot port (74) of the switching valve (70) via the first pilot air line (32). )
The spool (72) moves to the right as shown in
And the first outlet (75) communicate with each other to open the first channel (I) and close the second channel (II) to close the second outlet (7).
7) communicates with the second exhaust port (79). The compressed air introduced from the introduction port (73) into the switching valve (70) passes through the first flow path (I) and passes through the forward passage (94) to the forward port of the cylinder (82). (86) and retreat pipeline (92)
The compressed air inside is discharged from the second discharge port (79), the plunger (83) moves forward, that is, descends, and the shutter (81) is closed. [4] When the box (S) is further transported and comes off the rear limit switch (93), the supply of pilot air to the first pilot port (74) is stopped, and the switching valve (70) is
(72) maintains the state of being moved to the right (FIG. 3A). In this state, the first flow path (I) is opened and the shutter (81) is kept closed while the compressed air is supplied to the forward pipe (94). [5] Wait for the next box (S) to be transported.

[0007]

In the shutter opening / closing device (80), when the boxes (S) are conveyed one by one at a predetermined interval, the opening and closing of the shutter (81) is smoothly controlled as described above. Is done. However, when a plurality of boxes (S) are conveyed without delay, the latter limit switch (9
Step 3) is continuously performed, and the shutter (81) is kept closed. The box (S) is further transported here and the shutter (8
1) When the front limit switch (91) is hit, the switching valve (7
The shutter (81) must be opened by supplying pilot air to the second pilot port (76) of (0). But,
Since pilot air is also supplied to the first pilot port (74) by the rear limit switch (93), equal pressure is applied to the left and right pilot ports (74) and (76), and the spool (72) moves. Without opening the shutter (81).

Accordingly, a pressure reducing valve (96) is provided between the first pilot port (74) of the switching valve (70) for closing the shutter (81) and the latter-stage limit switch (93) to provide two limit valves. When the switches (91) and (93) are hit at the same time, the pilot air pressure on the first pilot port (74) side is lowered so that the second pilot port (76) side is prioritized. That is, when the opening-closing is instructed at the same time, the opening is prioritized to avoid the collision of the mail box (S) with the shutter (81).

Therefore, the conventional switching valve cannot switch the flow path when the pilot air is simultaneously supplied to the two pilot ports. In the above-described shutter opening / closing device, a pressure reducing valve is added to the control circuit. Opening and closing control.

In view of the above background art, the present invention has a priority circuit that can open one of the flow paths preferentially when the pilot fluid is simultaneously supplied to the pilot port for switching the opening and closing of the two flow paths. It is an object of the present invention to provide a switching valve, a control device that controls various operating devices using the switching valve with a priority circuit, and a shutter opening / closing device that controls opening and closing operations of a shutter.

[0011]

In order to achieve the above object, a switching valve with a priority circuit according to the present invention is provided on a sleeve (11).
A hollow portion (12) provided with an inlet (13) for introducing a fluid into the valve, a first outlet (14) and a second outlet (15) for sending the fluid out of the valve, and penetrating in the axial direction; A spool (20) is movably fitted in the axial direction, and the spool (20) is moved in one direction based on a pilot fluid supplied to a first pilot port (18) at one end of the sleeve (11). Move,
The first flow path (I) is opened by communicating the introduction port (13) with the first outlet (14), and based on the pilot fluid supplied to the second pilot port (19) on the other end side. The spool (20) is moved in the opposite direction to open and close the flow path so as to open the second flow path (II) by connecting the introduction port (13) and the second discharge port (15). A switching valve, wherein a pressure receiving area (D ₂ ) of the pilot fluid at the second pilot port (19) is formed larger than a pressure receiving area (D ₁ ) at the first pilot port (18). I do.

In the switching valve with priority circuit, when the pilot fluid having the same pressure is supplied to the first pilot port (18) and the second pilot port (19) simultaneously,
Due to the difference in the pressure receiving areas (D ₂ > D ₁ ), the second pilot port (19) has a larger force than the supplied fluid pressure.
Therefore, the second pilot port (19) has priority over the first pilot port (18), and the spool (20) moves in the opposite direction to open the second flow path (II). Therefore, in addition to the case where the fluid pressure is applied to only one pilot port and the case where the fluid pressure is applied to both pilot ports, the predetermined flow path can be switched.

The control device of the present invention performs two types of operation switching control using the switching valve with a priority circuit, and performs a first operation by supplying a working fluid to a first port. , An operation unit that performs a second operation by being supplied to a second port, and a first unit that instructs the first operation.
A first signal generator for generating a signal; a second signal generator for generating a second signal for instructing the second operation; and the switching valve with a priority circuit according to claim 1, wherein only the first signal is provided. When generated, a pilot fluid is supplied to a first pilot port of the switching valve with a priority circuit, a first flow path of the switching valve with a priority circuit is opened, and the working fluid is supplied to a first port of the operating unit. When the first operation is performed and only the second signal is generated, the second valve of the switching valve with the priority circuit is provided.
The pilot fluid is supplied to the pilot port, the second flow path of the switching valve with the priority circuit is opened, the fluid is supplied to the second port of the operation unit, and the second operation is performed, and the first signal is transmitted. And when the second signal is generated simultaneously,
A pilot fluid is simultaneously supplied to the first pilot port and the second pilot port of the switching valve with a priority circuit, and the second pilot port (19) is given priority by the pressure receiving area difference (D ₂ > D ₁ ), so that the second flow is supplied. A path is opened, and the working fluid is supplied to a second port of the operation unit to perform a second operation.

The control device switches the flow path of the working fluid by supplying a pilot fluid to a predetermined pilot port of the switching valve with a priority circuit based on each signal generated by the two signal generating units. The operation is switched by supplying a working fluid to one of the two operation ports. In the switching valve with a priority circuit, the second flow path based on the second pilot port having a large pressure receiving area is preferentially opened, and in addition to the case where only one signal is generated, both signals are simultaneously generated. Also in this case, a predetermined flow path switching is performed, and one operation can be preferentially performed.

Further, the shutter opening / closing device of the present invention comprises:
The opening and closing operation switching control is performed by using the switching valve with the priority circuit. A shutter for opening and closing the shutter (81) by supplying a working fluid to a forward port (86) or a backward port (85) of the cylinder (81) to move the plunger (83) forward and backward. A driving unit, a front-stage detector (91) that is provided in front of the shutter (81), detects the presence of the conveyed object (S), and generates an opening signal for opening the shutter (81); 81), which is provided at the subsequent stage and detects the presence of the conveyed object (S) and generates a closing signal for closing the shutter (81).
3) and the switching valve with a priority circuit according to claim 1, wherein the switching valve with a priority circuit (1
0), a pilot fluid is supplied to a first pilot port (18), the first flow path (I) of the switching valve with priority circuit (10) is opened, and the working fluid is supplied to one port of the shutter driving unit. (86), the shutter (81) is closed, and when only the opening signal is generated, the pilot fluid is supplied to the second pilot port (19) of the switching valve with priority circuit (10). Then, the second flow path (II) of the switching valve with priority circuit (10) is opened, the working fluid is supplied to another port (85) of the shutter driving unit, and the shutter (81) is opened. When the closing signal and the opening signal are simultaneously generated, the pilot fluid is simultaneously supplied to the first pilot port (18) and the second pilot port (19) of the switching valve with priority circuit (10), and the pressure receiving area priority difference (D _2> D ₁₎ by the second pilot port (19) Is the second flow path (II) is opened, the working fluid is supplied to the other port (85) of said shutter driving unit said shutter (81) is characterized in that it is open.

The shutter opening and closing device has two detectors.
(91) Based on the signals generated in (93), the pilot fluid is supplied to the predetermined pilot port (18) (1) of the switching valve (10) with a priority circuit.
9 to switch the flow path of the working fluid, and supply the working fluid to either the forward port (86) or the retreat port (85) of the shutter drive unit, thereby causing the plunger (8
The two types of operation switching of forward and backward of 3) are performed, and the shutter (81) attached to the plunger (83) is moved to open and close the shutter (81). In the switching valve with priority circuit (10), since the second flow path (II) based on the second pilot port (19) having a large pressure receiving area is opened preferentially, only one of the open signal and the close signal is provided. Is generated, and also when both signals are simultaneously generated, a predetermined flow path switching is performed, and the opening operation can be preferentially performed.

[0017]

1A, 1B and 1C show an embodiment of a switching valve with a priority circuit according to the present invention.

The switching valve with priority circuit (10) is provided with a sleeve (1).
1) and a comb-shaped spool (20) fitted into a hollow portion (12) having a circular cross section penetrating in the axial direction of the sleeve (11), and a fluid added to both ends of the spool (20). By moving the spool (20) in the axial direction based on the pressure, the flow path of the fluid introduced into the valve is switched in two directions.

In the sleeve (11), the hollow part (12) has a small diameter part (12a) and a large diameter part (12b) continuously formed in a stepped manner,
A pilot port to which pilot air is supplied is formed at each open end. That is, the second pilot port (19) on the other end is formed to have a larger diameter than the first pilot port (18) formed on one end of the small diameter.
Further, a small diameter portion (12) of the outside and the hollow portion (12) is provided on the peripheral wall portion.
a) Opening port (13), 1st outlet
(14) and a second outlet (15) are formed, and further, a first exhaust port (16) and a second exhaust port (17) are formed. Of these ports, the inlet (13), the first outlet (14), and the second outlet (15) constitute a fluid flow path, and the first outlet (14) and the second outlet (15). ) Is a connection port with a pipeline for sending a fluid to various operating devices. The inner surface of the land between the ports, that is, the inner surface of the small-diameter portion (12a) of the hollow portion (12) forms a sliding surface in contact with the spool (20).

On the other hand, the spool (20) has three sliding portions (22), (23) and (24) provided at predetermined intervals on a rod (21), and these sliding portions (22), (23) and (24) are provided. Is the hollow portion (1) of the sleeve (11).
It is inscribed in the small-diameter portion (12a) of 2), and performs switching of the flow path opening and closing and flow rate adjustment according to the amount of movement of the spool (20). The outermost sliding portion (22) also functions as a first pressure receiving portion that receives pilot air at the first pilot port (18). The other end of the rod (21) has a large diameter portion (12) of the hollow portion (12).
A second pressure receiving portion (25) inscribed in b) and receiving pilot air at the second pilot port (19) is provided.
Therefore, the spool (20) is connected to the second pilot port (1
9) The pressure receiving area (D ₂ ) of the second pressure receiving portion (25) is formed larger than the pressure receiving area (D ₁ ) of the first pressure receiving portion (sliding portion) (22) of the first pilot port (18). I have.

The flow path of the switching valve with priority circuit (10) is switched as follows according to the supply state of the pilot air to the first and second pilot ports (18) and (19). [1] When pilot air is supplied only to the first pilot port As shown in FIG. 1A, when pilot air is supplied to the first pilot port (18) on the left side of the drawing, the first pressure receiving portion ( (Sliding part) (22) The spool (20) moves to the right, the fluid inlet (13) communicates with the first outlet (14) on the left, and the first channel (I) is opened. On the other hand, the second outlet (15) is the second exhaust port
Opened in communication with (17). [2] When pilot air is supplied only to the second pilot port As shown in FIG. 1B, when pilot air is supplied to the second pilot port (19) on the right side in the drawing, the spool
(20) moves to the left and the inlet (13) and the second outlet (15) on the right
And the second flow path (II) is opened. Meanwhile, the first
The outlet (14) communicates with the first exhaust port (16) and is opened. [3] When pilot air is supplied to both pilot ports As shown in FIG. 1C, pilot air of the same pressure is supplied to the first pilot port (18) and the second pilot port (19) simultaneously. Then, the difference (D ₂ > D ₁ ) in the pressure receiving area between the second pressure receiving portion (25) and the first pressure receiving portion (sliding portion) (22) gives
At the second pilot port (19), the force is larger than the supplied fluid pressure. Therefore, the second pilot port (1
9) has priority over the first pilot port (18) and
0) moves to the left, the inlet (13) communicates with the second outlet (15), and the second channel (II) is opened. Also, the first outlet (14)
Is opened in communication with the first exhaust port (16). [4] When pilot air is not supplied to both pilot ports Maintain the spool (20) position immediately before.

In the switching valve with priority circuit (10), compressed air is exemplified as the pilot fluid for moving the spool (20), but the pilot fluid in the present invention may be gas-liquid. Also, in the control device and the shutter opening / closing device of the present invention described later, the gas and liquid of the pilot fluid are not limited. Further, the fluid (working fluid) for switching the flow path by the switching valve with priority circuit, the control device, and the shutter opening / closing device of the present invention may be gas-liquid.

FIG. 2 shows a shutter opening and closing device as an example of a control device using the switching valve with priority circuit (10).

The shutter opening / closing device (40) is installed on a box for transferring parts and the like, for example, on a transfer path of a transfer conveyor for packing. When the box (S) is transferred, the shutter is opened and closed. (81) is opened to receive the box (S), and when the loading is completed, the shutter (81) is closed to prevent foreign matter from entering the inside of the apparatus. The shutter (81) is a cylinder (82)
Attached to the tip of a plunger (83) removably inserted into the inside, the opening and closing of the shutter (81) is performed by the reciprocating operation of the plunger (83) by switching the flow path of the switching valve with priority circuit (10). .

In FIG. 2, (30) is an air pump,
(31) is a working fluid supply pipe for supplying compressed air generated by an air pump (30) as a working fluid of the cylinder (82) to an inlet of the switching valve with priority circuit (10), (32) Is a switching valve with a priority circuit using the compressed air as pilot air (10)
The first pilot air line (33) for supplying the first pilot port (18) to the second pilot port (19) of the switching valve (10) with a priority circuit using the compressed air as pilot air. This is a pilot air line.

In the shutter opening / closing device (40) of the cleaning device, the opening / closing operation of the shutter (81) when the box (S) is conveyed at a predetermined interval is as follows. [1] The box (S) conveyed by the conveyor (90) is the front limit switch before the shutter (81)
When (91) is hit, an opening signal for opening the shutter (81) is generated, and based on this opening signal, the second pilot air line is opened.
Pilot air is supplied to the second pilot port (19) of the switching valve with priority circuit (10) via (33). And
As shown in FIG. 1 (B), the spool (20) moves to the left, the inlet (13) communicates with the second outlet (15), and the second flow path (II) is opened. The compressed air introduced from the introduction port (13) to the switching valve with priority circuit (10) passes through the second flow path (II), and retreats the cylinder (82) through the retreat pipe (92). It is supplied to the side port (85), the plunger (83) moves backward, that is, rises, and the shutter (81) is opened. [2] The box (S) is carried into the apparatus from the opened shutter (81). When the box (S) passes through the shutter (81) and comes off the front limit switch (91),
The supply of pilot air to the second pilot port (19) is stopped, and the switching valve with priority circuit (10) maintains the state in which the spool (20) is moved to the left (FIG. 1B). .
In this state, the second flow path (II) is opened and the shutter (81) is kept open while the compressed air is being supplied to the retreat pipe (92). [3] The box (S) carried inside is a shutter (82)
After hitting the latter limit switch (93), the shutter (81)
Is generated, and based on the closing signal, pilot air is supplied to the first pilot port (18) of the switching valve with priority circuit (10) through the first pilot air line (32). Is done. Then, the spool (20) moves to the right as shown in FIG.
4), the first flow path (I) is opened, and the second flow path (II) is closed, so that the second outlet (15) and the second exhaust port are opened.
(17) communicates. The compressed air introduced into the switching valve with priority circuit (10) from the introduction port (13) passes through the first flow path (I) and passes through the forward pipe (94) to the cylinder (82). While being supplied to the forward port (86), the compressed air in the retreat pipe (92) is discharged from the second exhaust port (17), and the plunger (8
3) moves forward, that is, descends, and the shutter (81) is closed. [4] When the box (S) is further conveyed and comes off the rear limit switch (93), the supply of pilot air to the first pilot port (18) is stopped, and the switching valve with priority circuit (10)
Is a state in which the spool (20) has been moved to the right (FIG. 1).
(A)) is maintained. In this state, the first flow path (I) is opened and the shutter (81) is kept closed while the compressed air is supplied to the forward pipe (94). [5] Wait for the next box (S) to be transported.

When a plurality of boxes (S) are conveyed without any interval and traffic jams before and after the shutter (81), the shutter (81) is controlled to open and close as follows.

Rear limit switch after shutter (81)
If the front limit switch (91) is hit by the next box (S) before the (93) comes off, the two limit switches (91) and (93) are hit at the same time, and the open signal and the close signal are output. Are both generated and based on these signals,
As shown in FIG. 1C, pilot air is supplied to both the first pilot port (18) and the second pilot port (19). At this time, the difference (D ₂ > D ₁ ) in the pressure receiving area between the second pressure receiving portion (25) and the first pressure receiving portion (sliding portion) (22) gives
At the second pilot port (19), the force is larger than the supplied fluid pressure. Therefore, the second pilot port (1
9) has priority over the first pilot port (18) and
0) moves to the left, the inlet (13) communicates with the second outlet (15), and the second channel (II) is opened. Then, the introduction port (1
The compressed air introduced from 3) into the switching valve with priority circuit (10) passes through the second flow path (II) and passes through the retreat line (92) to the retreat port (85) of the cylinder (82). ) Supplied to the plunger
The shutter (81) is opened (83) is retracted, the shutter (81) is opened, and the box (S) is conveyed into the apparatus.

In the shutter opening / closing device (40), when the plunger (83) is retracted (upward), the shutter (8) is opened.
1) is opened and the shutter (81) is closed when moving forward (downward). However, opening and closing can be performed by the reverse moving operation.

The shutter driving unit according to claim 3 of the present invention is the shutter opening / closing device (40) according to the embodiment.
Cylinder (82), plunger (83), shutter
(81), corresponding to the forward port (86) and the reverse port (85). Similarly, the conveyed object corresponds to the box (S), the front detector corresponds to the front limit switch (91), the rear detector corresponds to the rear limit switch (93), and the working fluid corresponds to the compressed air.

The shutter opening / closing device (10) opens and closes the shutter (81) as a control operation in the control device according to the second aspect of the present invention. Therefore, the operating part in claim 2 is a shutter driving part in the shutter opening and closing device (10), that is, the cylinder (82), the plunger.
(83), the shutter (81), the forward port (86), and the backward port (85), the first operation being forward movement of the plunger (83) (closing the shutter), and the second operation being plunger (83). The first port corresponds to the forward port (86), and the second port corresponds to the backward port (85).
Hereinafter, similarly, the first signal generation unit performs the subsequent-stage limit switch (9
In 3), the second signal generation unit supplies the preceding limit switch (91) with
The working fluid corresponds to the compressed air.

The control device of the present invention performs the preferential flow path switching of the working fluid only by the switching valve with the priority circuit, and performs the operation switching in the operation section. For this reason, an additional component such as a pressure reducing valve is not required to perform one operation preferentially, and the apparatus is simplified and space is saved. Further, since the flow path switching and the operation instruction are all performed by the fluid pressure and do not require an electric circuit, it can be suitably used for a control device requiring an explosion-proof structure. Examples of the switching operation include forward / backward control of the plunger in the cylinder, control of the rotation direction of the motor, and the like.

Further, the shutter opening / closing device of the present invention comprises:
Only the switching valve with the priority circuit switches the flow path of the working fluid preferentially, and switches the opening and closing of the shutter. This eliminates the need for a pressure reducing valve for prioritizing the opening operation as in a conventional switchgear, thereby simplifying the device and saving space.

[0034]

As described above, the switching valve with a priority circuit according to the present invention has an inlet for introducing fluid into the sleeve, a first outlet and a second outlet for sending fluid out of the valve. Is provided, and a spool is movably fitted in an axial direction into a hollow portion penetrating in the axial direction, and moves the spool in one direction based on a pilot fluid supplied to a first pilot port on one end side of the sleeve. Opening the first flow path by communicating the introduction port and the first outlet, moving the spool in the opposite direction based on the pilot fluid supplied to the second pilot port on the other end, A switching valve for opening and closing a flow path so as to open a second flow path by connecting an introduction port and a second discharge port, wherein a pressure receiving area of a pilot fluid at the second pilot port is provided. Since D ₂₎ is larger than the pressure receiving area of the first pilot port (D _1), the pilot air simultaneously the pressure in the first pilot port and the second pilot port is supplied, the difference in pressure receiving area (D ₂ > D ₁ ), the second pilot port has a larger force than the supplied fluid pressure. For this reason,
The second pilot port is given priority over the first pilot port, and the spool moves in the opposite direction to open the second flow path. Therefore, in addition to the case where the fluid pressure is applied to only one pilot port and the case where the fluid pressure is applied to both pilot ports, the predetermined flow path can be switched.

Further, the control device of the present invention performs two kinds of operation switching control of the first operation and the second operation in the operation section using the switching valve with the priority circuit, and comprises a first signal section. The pilot fluid is supplied to a predetermined pilot port of the switching valve with a priority circuit based on the first signal generated by the first signal and the second signal generated by the second signal generation unit, and the flow path of the working fluid is switched. The operation is switched by supplying a working fluid to one of the first operation port and the second operation port. In the switching valve with a priority circuit, the second valve based on the second pilot port having a large pressure receiving area is provided.
In addition to the case where the flow path is opened preferentially and only one signal is generated, the predetermined flow path switching is performed also when both signals are simultaneously generated, and one operation is preferentially performed. Can be made. The operation control by such preferential flow path switching has conventionally been performed by combining a switching valve and a pressure reducing valve, but according to the present invention, it can be performed only by a switching valve with a priority circuit, The control device is simplified and space is saved. Further, the switching of the flow path and the operation instruction are performed by applying a fluid pressure through a predetermined pipeline, and an electric circuit is not required.

Further, the shutter opening / closing device of the present invention comprises:
The opening / closing control of the shutter attached to the plunger is performed by switching between two types of operation of the forward and backward movements of the plunger in the cylinder in the shutter driving unit using the switching valve with the priority circuit, and is provided at the front stage of the shutter. A pilot fluid is supplied to a predetermined pilot port of a switching valve with a priority circuit based on an open signal generated in a front-stage detector and a close signal generated in a rear-stage detector provided after a shutter, and a flow path of a working fluid. And the operation is switched by supplying the working fluid to either the forward port or the reverse port of the cylinder.
In the switching valve with a priority circuit, the second valve having a large pressure receiving area is provided.
The second flow path based on the pilot port is preferentially opened,
In addition to the case where only one signal is generated, the predetermined flow path switching is performed when both signals are simultaneously generated,
Opening of the shutter, which is one of the operations, can be preferentially performed. Therefore, for example, when a conveyed object arrives before the shutter, the shutter is opened and accepted, the shutter is closed after being accepted, and even if the conveyed object is stagnant at the rear detector position after the shutter, the next conveyed object is before the shutter. The shutter can be opened and closed when it arrives. Further, similarly to the control device of the present invention, open / close switching can be performed only by the switching valve with the priority circuit, and the device is simplified, space is saved, and an explosion-proof structure is required because an electric circuit is not required. It can be used favorably even in situations.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a switching valve with a priority circuit of the present invention, in which (A) is a state in which pilot air is supplied only to a first pilot port and a first flow path is opened;
(B) is a state where pilot air is supplied only to the second pilot port and the second flow path is opened, and (C) is a state where pilot air is supplied to both pilot ports and the second flow path is opened. Is shown.

FIG. 2 is a schematic connection diagram showing one embodiment of a control device and a shutter opening / closing device of the present invention.

FIG. 3 is a cross-sectional view showing a conventional switching valve, in which (A) shows a state in which pilot air is supplied to a first pilot port and a first pilot port is supplied.
(B) shows a state in which pilot air is supplied to the second pilot port and the second flow path is opened.

FIG. 4 is a schematic connection diagram showing a conventional shutter opening / closing device.

[Explanation of symbols]

 10 switching valve with priority circuit 11 sleeve 12 hollow part 12a small diameter part 12b large diameter part 13 inlet 14 first outlet 15 second outlet 18 first pilot port 19 second pilot Port 20 Spool 40 Shutter opening / closing device 81 Shutter 82 Operating part (cylinder, shutter driving part) 83 Operating part (plunger, shutter driving part) 85 Second port (retreat port, shutter driving part) 86 ... First port (forward port, shutter drive section) 91 second signal generation section (front limit switch) 93 first signal generation section (back limit switch) I first flow path II second flow path S Conveyed goods (mail box)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Osamu Nakazato, Inventor, 6224, Kaiyama-cho, Sakai City Showa Aluminum Co., Ltd. F-term (reference) 3H056 AA05 BB01 BB24 CA02 CB02 CD04 DD02 GG02 3H067 AA17 CC41 CC44 CC47 DD05 DD12 DD33 3H089 AA58 BB28 BB30 CC01 DA02 DB45 DB48 FF01 FF13 GG03 JJ07

Claims (3)

[Claims] An inlet (13) for introducing a fluid into a valve, a first outlet (14) and a second outlet (15) for sending a fluid out of the valve are provided in a sleeve (11), A spool (20) is movably fitted in the axial direction in a hollow portion (12) penetrating in the axial direction, and a pilot fluid supplied to a first pilot port (18) on one end side of the sleeve (11). The spool (20) is moved in one direction based on the
The first flow path (I) is formed by communicating with the outlet (14).
The spool (20) is moved in the opposite direction based on the pilot fluid supplied to the second pilot port (19) on the other end side, and the inlet (13) and the second outlet (15) are And a switching valve for switching the opening and closing of the flow path so as to open the second flow path (II) by opening the second flow path (II), wherein the pressure receiving area (D ₂ ) of the pilot fluid at the second pilot port (19) is the first pressure. A switching valve with a priority circuit, wherein the switching valve is formed to be larger than a pressure receiving area (D ₁ ) in a pilot port (18). 2. An operation unit that performs a first operation by supplying a working fluid to a first port, and performs a second operation by being supplied to a second port; and a first unit that instructs the first operation. A first signal generation unit that generates a signal; a second signal generation unit that generates a second signal that instructs the second operation; and the switching valve with a priority circuit according to claim 1, wherein only the first signal is provided. When generated, a pilot fluid is supplied to a first pilot port of the switching valve with a priority circuit, a first flow path of the switching valve with a priority circuit is opened, and the working fluid is supplied to a first port of the operating unit. When the first operation is performed and only the second signal is generated, a pilot fluid is supplied to the second pilot port of the switching valve with the priority circuit and the second pilot port of the switching valve with the priority circuit is supplied. The flow path is opened, and the moving fluid is When the second signal is supplied to the second port and the second operation is performed, and the first signal and the second signal are simultaneously generated, the pilot fluid is simultaneously supplied to the first pilot port and the second pilot port of the switching valve with the priority circuit. Is supplied, the second pilot port (19) is prioritized due to the difference in pressure receiving areas (D ₂ > D ₁ ), the second flow path is opened, and the working fluid is supplied to the second port of the operating section. A control device wherein the second operation is performed. 3. A plunger (83) is removably fitted into a cylinder (82), a shutter (81) is attached to the plunger (83), and a forward port (86) of the cylinder (81). Alternatively, a shutter drive unit that opens and closes the shutter (81) by supplying working fluid to the retreat-side port (85) to move the plunger (83) forward and backward; A front-stage detector (91) that detects the presence of the object (S) and generates an open signal for opening the shutter (81); A rear-stage detector (93) for detecting and generating a closing signal for closing the shutter (81); and a switching valve with a priority circuit according to claim 1, wherein the priority is given when only the closing signal is generated. Pilot to first pilot port (18) of switching valve with circuit (10) The fluid is supplied, the first flow path (I) of the switching valve with priority circuit (10) is opened, and the working fluid is supplied to one port (86) of the shutter driving unit to supply the shutter (81). Is closed, and when only the opening signal is generated, a pilot fluid is supplied to the second pilot port (19) of the switching valve with priority circuit (10), and the switching valve with priority circuit (10) is supplied. The second flow path (II) is opened, the working fluid is supplied to another port (85) of the shutter drive unit, the shutter (81) is opened, and the close signal and the open signal are simultaneously generated. Sometimes, the first pilot port of the switching valve with priority circuit (10)
The pilot fluid is supplied to the (18) and the second pilot port (19) at the same time, and the second pilot port (19) is prioritized due to the pressure receiving area difference (D ₂ > D ₁ ), and the second flow path (II) is opened. A shutter opening / closing device, wherein the shutter is opened and the working fluid is supplied to another port (85) of the shutter driving unit to open the shutter (81).