JP4195846B2 - Pressure switching valve - Google Patents

Description

  The present invention relates to a conveyance device that adsorbs and conveys a small workpiece, and more particularly to a pressure switching valve that controls adsorption and separation of the workpiece.

  7 and 8 show a position pattern of a conventional suction transfer pressure switching valve. The first electromagnetic valve 1 is connected to the suction pad 3 via a pipe 2, and the second electromagnetic valve 4 is connected to the pipe 2 via a throttle valve 5. The throttle valve 5 is provided outside the main body portions of the first and second electromagnetic valves 1 and 4.

  The first electromagnetic valve 1 is supplied with a negative pressure V for adsorbing a workpiece to the suction pad 3, and the second electromagnetic valve 4 is supplied with a positive pressure P for releasing the workpiece from the adsorption pad 3. . When the workpiece is attracted, the first electromagnetic valve 1 is opened, and the negative pressure V is supplied to the suction pad 3 via the pipe 2 to attract the workpiece. Further, during the work detachment operation, the second electromagnetic valve 4 is opened, the positive pressure P is supplied to the suction pad 3 through the throttle valve 5 and the pipe 2, and the work is detached. At this time, the air flow rate is adjusted by the throttle valve 5 to prevent the workpiece from scattering.

FIG. 9 shows an example in which the throttle valve is built in the base portion 6 of the first and second electromagnetic valves 1 and 4, and the operation thereof is the same as that shown in FIG.
10 and 11 show a pressure switching valve controlled by two single-acting solenoids 8 and 9 in an all-port block composed of a three-position five-port valve. As shown in FIG. 10, a speed controller 7 is interposed in the pipe 2 connected to the suction pad 3, and a sufficient flow rate is secured when negative pressure is supplied to the suction pad 3, and a flow rate is restricted when positive pressure is supplied. Is done.

  In such a pressure switching valve, as shown in FIG. 11, when the solenoid 8 is excited, the negative pressure V is supplied to the suction pad 3 via the speed controller 7, and when the solenoid 9 is excited, the positive pressure is supplied. P is supplied to the suction pad 3 via the speed controller 7.

  In the pressure switching valve shown in FIGS. 7 and 8, two electromagnetic valves are required, and the throttle valve 5 is provided outside the first and second electromagnetic valves 1 and 4. Therefore, since the external dimensions increase, there is a problem that it is difficult to secure a mounting space when mounting on a transport device.

In the configuration shown in FIG. 9, by providing the throttle valve 5 in the base portion 6, the outer dimensions of the base portion 6 increase.
In the configuration shown in FIGS. 10 and 11, the speed controller 7 is provided separately from the solenoid valve, and the speed controller 7 needs to ensure a sufficient free flow rate when supplying negative pressure. Have difficulty. Accordingly, an increase in outer dimensions is caused, and it is difficult to secure a mounting space.

  An object of the present invention is to provide a pressure switching valve having a simple configuration and capable of reducing the external dimensions.

In the first aspect of the present invention, a flow path communicating with the plurality of input ports and one output port is formed, and the spool shaft is movably supported in the flow path, and as the spool shaft moves, Pressure switching valve that switches communication of the flow path or cuts off communication, and can select supply of positive pressure and negative pressure supplied to the input port to the output port and maintenance of negative pressure with the output port The throttle port portion is attached to the main body portion of the all-port block, and the throttle valve portion is composed of a communication passage that connects the two ports of the main body portion and a throttle valve that is interposed in the communication passage. The spool shaft interposes the throttle valve for adjusting the positive pressure supplied to the communication path between the positive pressure input port and the output port when the positive pressure is supplied, and the negative pressure. The flow from the input port side to the output port Of blocking the communication, the so not interposed the throttle valve between the negative pressure and the negative pressure of the input port and the output port during the supply of, characterized in that it is switching control.

According to a second aspect of the present invention, the throttle valve is constituted by a needle provided in the communication path so as to be able to appear and retract.
In the invention according to claim 3 , the communication passage is formed in the throttle valve portion so as to match the two ports formed in advance.

  ADVANTAGE OF THE INVENTION According to this invention, the pressure switching valve which can aim at size reduction of a simple structure and an external dimension can be provided.

  Hereinafter, an embodiment in which the present invention is embodied in a pressure switching valve used in an adsorption conveyance device will be described with reference to the drawings. The pressure switching valve shown in FIG. 1 is composed of an all-port block composed of a 3-position 5-port valve, and includes a main body part 11, a base part 12, first and second pilot valve parts 13, 14, first and second parts. Piston chambers 15 and 16 and a throttle valve portion 17.

  A flow path 18 that communicates with five ports formed in the base portion 12 is formed in the main body 11, and a spool shaft 19 is movably supported in the flow path 18. The connection or blocking of each port is selected by the movement of the spool shaft 19.

  The first and second pilot valve portions 13 and 14 are respectively provided with first and second solenoids 20 and 21, and the first and second solenoids 20 and 21 are controlled by excitation or non-excitation control. The pilot valve is opened and closed. The air pressure in the first and second piston chambers 15 and 16 is controlled based on the opening and closing of the pilot valve, so that the pistons 22a and 22b move.

  Both ends of the spool shaft 19 are attached to the pistons 22a and 22b. Therefore, when the pistons 22a and 22b move based on the control of the first and second solenoids 20 and 21, the spool shaft 19 moves.

  It should be noted that one of the first and second solenoids 20 and 21 is excited, or a state where both are not excited is selected. When the first solenoid 20 is excited, the spool shaft 19 moves to one side, and when the second solenoid 21 is excited, the spool shaft 19 moves to the other side. When neither the first solenoid 20 nor the second solenoid 21 is excited, the spool shaft 19 is in an intermediate position, that is, in a neutral state.

  The configurations and operations of the first and second pilot valve portions 13 and 14, the first and second piston chambers 15 and 16, the main body portion 11, and the spool shaft 19 are the same as those of a known pressure switching valve. is there.

  Five ports 23 a to 23 e are formed in the base portion 12, and communicated with the flow path 18 through ports opened at the lower portion of the main body portion 11. The first and second ports 23a and 23b are used as input ports, and the third port 23c is used as an output port. The other ports are not used in this embodiment and remain sealed.

  A positive pressure P is supplied to the first port 23a, and a negative pressure V is supplied to the second port 23b. The third port 23c is connected to the suction pad 3 shown in FIG. 4 through a pipe.

  The throttle valve portion 17 is attached to the upper surface of the main body portion 11. Then, both ends of the communication passage 24 formed in the throttle valve portion 17 are connected to two ports opened on the upper surface of the main body portion 11.

  A needle 25 whose tip protrudes into the communication passage 24 is attached to the throttle valve portion 17 so as to be able to appear and retract with respect to the communication passage 24. Accordingly, the throttle valve 26 is formed by the communication path 24 and the needle 25, and the flow rate of the communication path 24 can be adjusted by adjusting the protruding amount of the needle 25 into the communication path 24.

  Seal members 27 are attached to the spool shaft 19 at a plurality of locations. As the spool shaft 19 moves, the first to third ports 23a to 23c and the communication passage 24 are communicated or sealed through the flow path 18. Stop is selected.

  As shown in FIG. 1, when the first solenoid 20 is excited, the second port 23 b and the third port 23 c are communicated with each other through the flow path 18 by the movement of the spool shaft 19. When the second solenoid 21 is excited, the first port 23a and the third port 23c communicate with each other via the flow path 18 and the throttle valve 26 by the movement of the spool shaft 19 as shown in FIG. Is done. When neither the first solenoid 21 nor the second solenoid 21 is excited, the first to third ports 23a to 23c are sealed without communicating with each other, as shown in FIG.

  Next, the operation of the pressure switching valve configured as described above will be described. When the first solenoid 20 is excited, as shown in FIG. 1, the second port 23b and the third port 23c are communicated, and the communication path 24 and the flow path 18 are blocked. Then, as shown in FIG. 4, the negative pressure V is supplied to the suction pad 3, and the workpiece can be sucked.

  Next, when the excitation of the first solenoid 20 is released, as shown in FIG. 2, the spool shaft 19 is moved to the neutral state, and the first to third ports 23 a to 23 c, the communication path 24 and the flow path 18 are moved. Are all blocked. Then, as shown in FIG. 5, the suction pad 3 is disconnected from the flow path 18, and the negative pressure is maintained. In this state, the work is maintained in the state of being sucked by the suction pad 3, and the transfer operation is performed in this state.

  Next, when the second solenoid 21 is excited, the first port 23a and the third port 23c are communicated via the communication path 24 as shown in FIG. Then, as shown in FIG. 6, the positive pressure P is supplied to the suction pad 3 through the communication path 24, and the workpiece is detached from the suction pad 3.

At this time, the positive pressure P supplied to the suction pad 3 can be adjusted as appropriate by the throttle valve 26 interposed in the communication passage 24.
With the pressure switching valve configured as described above, the following operational effects can be obtained.
(1) By the control of the first and second solenoids 20 and 21, the state in which the negative pressure V is supplied to the suction pad 3 and the supply of the negative pressure V and the positive pressure P are cut off, and the suction pad 3 Either a state in which the negative pressure is maintained or a state in which the positive pressure P is supplied to the suction pad 3 can be selected. Therefore, switching between the positive pressure P and the negative pressure V can be performed with one solenoid valve.
(2) When the positive pressure P is supplied, the supply pressure can be appropriately adjusted by the throttle valve 26. Accordingly, it is possible to prevent the workpiece from being scattered due to overpressure.
(3) When supplying the negative pressure V, the negative pressure can be supplied to the suction pad 3 without using the throttle valve 26. Therefore, a sufficient flow rate can be secured when supplying negative pressure.
(4) The throttle valve 26 can be constituted by the throttle valve portion 17 attached to the main body portion 11. Therefore, it is possible to measure downsizing of the pressure switching valve provided with the throttle valve by using the main body 11 constituting the existing pressure switching valve.

Each of the above embodiments may be implemented in the following manner.
-It can also be applied to solenoid valves other than 3 position 5 port valves.
The throttle valve 26 may have an arbitrary configuration other than the needle 25 that can appear and disappear in the communication path 24.

It is sectional drawing which shows one embodiment. It is sectional drawing which shows operation | movement of one Embodiment. It is sectional drawing which shows operation | movement of one Embodiment. It is explanatory drawing which shows operation | movement of one Embodiment. It is explanatory drawing which shows operation | movement of one Embodiment. It is explanatory drawing which shows operation | movement of one Embodiment. It is a perspective view which shows a prior art example. It is explanatory drawing which shows a prior art example. It is a perspective view which shows a prior art example. It is a perspective view which shows a prior art example. It is explanatory drawing which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Main body part 12 Base part 17 Throttle valve part 19 Spool shaft 23a Input port (1st port)
23b Input port (second port)
23c Output port (third port)
24 communication path 25 needle 26 throttle valve

Claims (3)

A flow path communicating with a plurality of input ports and one output port is formed, and a spool shaft is movably supported in the flow path, and the communication of the flow paths is switched according to the movement of the spool shaft , or In the pressure switching valve that cuts off the communication, the supply of positive pressure and negative pressure supplied to the input port to the output port and the negative pressure maintenance with the output port can be selected.
A throttle valve portion is attached to the main body portion of the all-port block, and the throttle valve portion is constituted by a communication passage communicating two ports of the main body portion and a throttle valve interposed in the communication passage, The spool shaft interposes the throttle valve that adjusts the positive pressure supplied to the communication path between the positive pressure input port and the output port when the positive pressure is supplied, and the negative pressure input port The flow control from the side to the output port is cut off , and switching control is performed so that the throttle valve is not interposed between the negative pressure input port and the output port when the negative pressure is supplied. Pressure switching valve. The pressure switching valve according to claim 1, wherein the throttle valve is configured by a needle provided so as to be able to appear and retract in the communication path . The pressure switching valve according to claim 1 or 2 , wherein the communication passage is formed in the throttle valve portion so as to match the two ports formed in advance .

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