JP2017065906A - Air on-off circuit and part feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air on-off circuit in which responsiveness of compressed-air injection is favorable, and in which a pressure of the compressed-air is stable during operation.SOLUTION: An air on-off circuit 1 supplies/exhausts compressed-air with respect to a part feeder 2 having an air supply/exhaust passage 21, and it includes a needle valve 5 for controlling a flow rate of the compressed-air and a four-port valve 6 arranged on the downstream of the needle valve 5. The four-port valve 6 is constituted so that it is switchable between a first switching position R for connecting an outlet of the needle valve 5 and an air supply/exhaust passage 21 of the part feeder 2, and a second switching position L for opening the outlet of the needle valve 5 and the air supply/exhaust passage 21 of the part feeder 2 to the atmosphere.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an air on / off circuit and a parts feeder that have good response of compressed air injection and can stabilize the pressure of compressed air during operation.

  Conventionally, workpieces (chips) such as electronic components are identified on the conveyance path, and workpieces with other appropriate postures are corrected while removing the inappropriate workpiece from the conveyance path or reversing the posture on the conveyance path. There is known a parts feeder capable of transporting to a predetermined supply destination (for example, Patent Document 1).

  In this type of parts feeder, for example, as shown in FIG. 3, the regulator 4 connected to the compressed air source 3, the three-port valve 106 disposed downstream of the regulator 4, and the downstream of the three-port valve 106. In general, the air on / off circuit 10 including the check valve needle valve (speed controller) 50 is applied to eliminate a workpiece having an inappropriate posture or correct the posture.

  The three-port valve 106 includes a first port 106a that communicates with the outlet of the regulator 4, a second port 106b that communicates with the air supply / discharge passage 21 of the parts feeder 2, and a third port 106c that communicates with the atmosphere. The three-port valve 106 allows the second port 106b and the third port 106c to communicate with each other via the passage 161 in the spool 160 and shuts off the first port 106a and the second port 106b when not energized. The compressed air supplied from 4 is closed in the vicinity of the first port 106a. On the other hand, when energized, the spool 160 is displaced, and the first port 106a and the second port 106b are communicated with each other via the passage 162 in the spool 160, so that the compressed air supplied from the regulator 4 is supplied to the needle valve with a check valve. 50.

  The needle valve 50 with a check valve adjusts the flow rate of the compressed air, and supplies the compressed air of a predetermined flow rate to the air supply / discharge passage 21 of the parts feeder 2. Further, the needle valve 50 with a check valve generates a free flow on the check valve 51 side when the energization to the 3-port valve 106 is turned off and a reverse flow of compressed air occurs, and the 3-port valve 106 Compressed air can flow toward

  By using such an air on / off circuit 10, the compressed air adjusted (depressurized) to a constant pressure by the regulator 4 is transferred to the workpiece W via the air supply / discharge passage 21 by opening / closing (ON / OFF) of the three-port valve 106. The workpiece W can be removed from the conveying path 20 or reversed on the conveying path 20 by the compressed air.

  By the way, in order to appropriately perform high-speed discharge and high-speed processing of the workpiece W in the parts feeder 2 as described above, when the compressed air is injected, the workpiece W is affected to other workpieces W adjacent to the workpiece W in an inappropriate posture. It is important to shorten the time for which the compressed air is blown to each workpiece W transported at a high speed so that the pressure rises and falls for each injection from the air on / off circuit 10. It is necessary to accelerate.

  In the air on / off circuit 10 shown in FIG. 3, by using a three-port valve 106 as an electromagnetic valve, the air is smoothly supplied during energization to accelerate the rise of the pressure of the compressed air, and the compression is performed in a state where a certain reached pressure is reached. When the air pressure is to be reduced (turned off), the residual pressure in the air piping path 7 between the 3-port valve 106 and the air supply / discharge path 21 is changed to the air supply / discharge path 21 (air discharge block) and 3 ports. Both valves 106 can be extracted and exhausted (released to the atmosphere), so that the fall of the pressure of compressed air (clearance) can be accelerated.

Japanese Patent Laying-Open No. 2015-30566

  However, in recent years, the miniaturization of the workpiece W has progressed (ultra miniaturization), and the time for which the compressed air can be blown onto the workpiece W by one injection for the proper removal and inversion of the workpiece W has become shorter and shorter. Yes. For this reason, the pressure of the compressed air injected from the air supply / discharge passage 21 is lowered, and the needle valve 50 with a check valve is used below the minimum operating pressure, and the free flow on the check valve side 51 does not function. Only the control flow on the needle valve side 52 tends to function. At this time, the needle valve side 52 is adjusted so that the flow rate is reduced, the piping resistance of the residual pressure exhaust is high, and the exhaust flow rate is small. Therefore, as shown in FIG. 4, the falling region in each injection There is a problem that the slope of A becomes gentle, the fall of the pressure of the compressed air becomes slow, and the fall response is lowered.

  In order to solve such a problem, as shown in FIG. 5, the needle valve 5 is arranged on the input side of the 3-port valve 106 instead of the needle valve 50 with a check valve, and the influence of the check valve at the time of exhaust is reduced. It can be considered to have a lost configuration. With such a configuration, the residual pressure in the air piping path 7 when the 3-port valve 106 is de-energized is appropriately released to the atmosphere from both the air supply / discharge path 21 and the 3-port valve 106. As shown in FIG. 6, it is considered that the slope of the falling region A in each injection becomes steep and the falling response is improved.

  However, in such an air on / off circuit 20, the pressure increases in the air piping path 7 between the needle valve 5 and the first port 106 a of the three-port valve 106 due to the compressed air supplied from the regulator 4 during the off-state. As shown in FIG. 6, the pressure of the first compressed air becomes higher than the pressure of the second and subsequent pressures, the pressure at the time of operation, that is, the initial pressure becomes unstable, and the workpiece cannot be processed stably. Problems arise.

  An object of the present invention is to effectively solve such problems, and to provide an air on / off circuit and a parts feeder in which compressed air injection response is fast and pressure during operation is stable. It is aimed.

  The present invention takes the following measures in view of the above problems.

  That is, the air on / off circuit of the present invention supplies / exhausts compressed air to / from an injection mechanism having an air supply / discharge path, and controls a flow rate control valve for adjusting the flow rate of the compressed air, A directional switching valve disposed downstream, wherein the directional switching valve has a first switching position that connects an outlet of the flow control valve and an air supply / discharge path of the injection target mechanism, and the flow control valve The outlet and the air supply / discharge path of the ejection target mechanism are configured to be switchable to a second switching position that opens to the atmosphere.

  With such a configuration, the compressed air that has passed through the flow control valve is moved from the direction switching valve to the atmosphere by setting the direction switching valve to the second switching position before supplying air to the air supply / discharge passage of the injection target mechanism. Since it opens inside, it can suppress that the pressure of compressed air becomes high between a flow control valve and a direction switching valve. Therefore, when the direction switching valve is first switched to the first switching position, the pressure of the first compressed air injected from the air supply / discharge path is higher than the pressure of the second and subsequent compressed air. Can be suppressed. Further, at the time of exhausting to the air supply / discharge path, that is, immediately after switching the direction switching valve to the second switching position, the residual pressure between the direction switching valve and the injection target mechanism is caused by the air supply / discharge path and the direction switching valve. Since both are appropriately released to the atmosphere, the fall of the pressure of the compressed air can be accelerated. Accordingly, it is possible to stabilize the pressure of the compressed air supplied to the air supply / exhaust passage during operation, improve the falling response, and accelerate the response of the compressed air injection.

  In order to exert the above effect stably, the direction switching valve includes a first port that communicates with an outlet of the flow control valve, a second port that communicates with an air supply / discharge path of the injection target mechanism, and an atmospheric region. At least a third port and a fourth port that communicate with each other, wherein the first port and the second port are communicated at the first switching position, and the first port and the second port are communicated at the second switching position. It is preferable that the switching valve has four or more ports that communicate with the third port or the fourth port, respectively.

  In particular, the flow control valve is preferably a needle valve. Alternatively, a needle valve with a check valve (speed controller) that is generally available is also suitable.

  Alternatively, in order to digitally control the opening / closing of the flow control valve instead of manually, it is preferable that the flow control valve is a proportional valve.

  On the other hand, in order to realize a parts feeder that can appropriately remove a workpiece from the conveyance path or change the posture on the conveyance path even when a miniaturized workpiece is conveyed on the conveyance path at high speed And using the air supply / exhaust path that is supplied and exhausted by the air on / off circuit, including the ejected mechanism that removes defective ones of the workpieces conveyed on the conveying path from the conveying path or changes the posture on the conveying path. A configuration is preferred.

  As described above, according to the present invention described above, air supply during operation is performed by opening the direction switching valve to the second switching position before supplying air and releasing the compressed air that has passed through the flow control valve from the direction switching valve to the atmosphere. Immediately after the direction switching valve is switched to the second switching position, the residual pressure between the direction switching valve and the injection target mechanism is reduced to the air supply / discharge path while stabilizing the pressure of the compressed air supplied to the exhaust path. It is possible to provide an air-on / off circuit and a parts feeder that can be released to the atmosphere appropriately from both the directional control valve and the directional switching valve to accelerate the fall of the pressure of the compressed air and to accelerate the response of the compressed air injection. .

The schematic diagram which shows the air on-off circuit which concerns on one Embodiment of this invention. The graph which shows the pressure at the time of the injection of the compressed air in the air on / off circuit. The schematic diagram which shows the structure of the conventional air on-off circuit. The graph which shows the pressure at the time of the injection of the compressed air in the air on / off circuit. The schematic diagram which shows the air on / off circuit which changed the conventional structure partially. The graph which shows the pressure at the time of the injection of the compressed air in the air on / off circuit.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, an air on / off circuit 1 according to an embodiment of the present invention is applied to a parts feeder 2 having a defective work processing means 22 as an injection target mechanism. The parts feeder 2 conveys a plurality of workpieces W along the conveyance path 20, and determines the quality by determining the posture of the workpiece W by a quality determination unit (not shown). The work W determined to be defective is removed from the conveyance path 20 at a predetermined processing position set in the conveyance path 20 or reversed on the conveyance path 20 by the defective workpiece processing means 22 to correct the posture.

  The defective workpiece processing means 22 has an air supply / discharge path 21 formed through the side wall 20a of the conveyance path 20 and through which compressed air supplied through the air on / off circuit 1 passes toward the processing position.

  The air on / off circuit 1 is connected to a compressed air source 3 (factory equipment) and includes a regulator 4 that reduces the compressed air supplied from the compressed air source 3 to a constant value regardless of the compressed air source 3 or the pressure on the load side. The needle valve 5 as a flow rate control valve that is arranged downstream of the regulator 4 and adjusts the flow rate of the compressed air decompressed by the regulator 4, and the direction switching valve (solenoid valve) that is arranged downstream of the needle valve 5 4 port valve 6 is provided. The compressed air source 3 and the regulator 4 are connected by a first air piping path 7a, the regulator 4 and the needle valve 5 are connected by a second air piping path 7b, and the needle valve 5 and the 4-port valve 6 are connected by a third air. The 4-port valve 6 and the air supply / discharge passage 21 are connected by a fourth air piping route 7d.

  The 4-port valve 6 includes a first port 6a that communicates with the third air piping path 7c, that is, the outlet of the needle valve 5, and a second port 6b that communicates with the fourth air piping path 7d, that is, the air supply / discharge path 21 of the parts feeder 2. A third port 6c and a fourth port 6d communicating with the atmosphere are provided. The 4-port valve 6 includes a first switching position R shown in FIG. 1B that allows the first port 6 a and the second port 6 b to communicate with each other via a passage 63 of the spool 60, and passages 61 and 62 of the spool 60. The first port 6a and the second port 6b are configured to be switchable to a second switching position L shown in FIG. 6 (a) that internally communicates with the third port 6c or the fourth port 6d, respectively. Note that, at the first switching position R, the third port 6c and the fourth port 6d communicate with each other through the passage 64.

  This switching is performed by the displacement of the spool 60 by energization of the electromagnetic solenoid 66 provided in the 4-port valve 6. When the electromagnetic solenoid 66 is not energized, the second switching position L shown in FIG. Thus, the compressed air supplied from the needle valve 5 to the 4-port valve 6 is inputted from the first port 6a, passes through the passage 61, and is always released from the third port 6c to the atmosphere. On the other hand, when the electromagnetic solenoid 66 is energized, the spool 60 is displaced to the first switching position R shown in FIG. 5B, and the compressed air supplied from the needle valve 5 is input from the first port 6a to the passage. The air is supplied from the second port 6b through the air supply 63 and supplied to the air supply / discharge passage 21. Thereby, compressed air is injected toward the predetermined position from the air supply / discharge path 21. When the energization of the electromagnetic solenoid 66 is stopped, the spool 60 is pushed back by the elastic force of the elastic body 65 and returns to the second switching position L. At this time, the residual pressure in the fourth air piping path 7d is The air supply / discharge passage 21 is opened to the atmosphere, and the second port 6b of the 4-port valve 6 is opened to the atmosphere through the passage 62 through the fourth port 6d.

  Therefore, before the injection of compressed air in which the 4-port valve 6 is in the second switching position L, the compressed air supplied from the needle valve 5 is released to the atmosphere from the 4-port valve 6, and the needle valve 5, the 4-port valve 6, As a result, it is possible to suppress an increase in pressure in the third air piping path 7c between the two ports, and when the 4-port valve 6 is switched to the first switching position R, an increase in the input pressure of the 4-port valve 6 is suppressed. Even if it is operated randomly, it can be operated at a constant pressure, and as shown in FIG. 2, the pressure of the compressed air at the time of injection can be made substantially the same for the first and second and subsequent shots.

  As for the rising response at the time of injection of compressed air, the start of pressure change is determined by the response time of an electromagnetic valve such as the 4-port valve 6. Further, the pressure rises with a certain slope due to the resistance of the fourth air piping path 7d, and the ultimate pressure is determined by the drive time of the solenoid valve. Furthermore, in order to match the target function and the workpiece W, further adjustment with the needle valve 5 determines the slope of the pressure rise.

  Immediately after the 4-port valve 6 is returned from the first switching position R shown in FIG. 1 (b) to the second switching position L shown in FIG. 1 (a), the 4-port valve 6 and the parts feeder 2 Since the residual pressure in the fourth air piping path 7d between the air supply / discharge passage 21 and the air supply / discharge passage 21 and the 4-port valve 6 is appropriately released to the atmosphere, the pressure of the compressed air falls. You can expedite.

  In addition, since the pressure and flow rate of the compressed air vary depending on the application such as reversal or exclusion of the workpiece W and the size of the workpiece W, the regulator 4 and the 4-port valve 6 are adjusted appropriately according to these.

  As described above, the air on / off circuit 1 according to the present embodiment supplies and exhausts compressed air to and from the defective work processing means 22 as an injection target mechanism having the air supply / discharge passage 21. A needle valve 5 as a flow control valve to be adjusted and a four-port valve 6 as a direction switching valve arranged downstream of the needle valve 5 are provided. The four-port valve 6 includes an outlet of the needle valve 5 and a parts feeder 2. The first switching position R for connecting the air supply / discharge path 21 and the second switching position L for opening the outlet of the needle valve 5 and the air supply / discharge path 21 of the parts feeder 2 to the atmosphere are configured to be switchable. The

  With such a configuration, the compressed air that has passed through the needle valve 5 is transferred to the 4-port valve 6 by setting the 4-port valve 6 to the second switching position L before supplying air to the air supply / discharge passage 21 of the parts feeder 2. Since the valve 6 is opened to the atmosphere, an increase in the pressure of the compressed air between the needle valve 5 and the 4-port valve 6 can be suppressed. Therefore, when the 4-port valve 6 is switched to the first switching position R, the pressure of the first compressed air injected from the air supply / exhaust passage 21 is higher than the pressure of the second and subsequent compressed air. It can suppress becoming high. Immediately after exhausting to the air supply / exhaust passage 21, that is, immediately after switching the 4-port valve 6 to the second switching position L, the residual pressure between the 4-port valve 6 and the parts feeder 2 is the air supply / exhaust passage. Since both the 21-port valve 4 and the 4-port valve 6 are appropriately opened to the atmosphere, the fall of the pressure of the compressed air can be accelerated. Therefore, the pressure of the compressed air supplied to the air supply / discharge passage 21 during operation can be stabilized, the falling response is good, and the compressed air injection response is fast. Can be realized.

  The 4-port valve 6 includes a first port 6a that communicates with the outlet of the needle valve 5, a second port 6b that communicates with the air supply / discharge passage 21 of the parts feeder 2, and a third port 6c and a fourth port that communicate with the atmosphere. 6d at least in the first switching position R, the first port 6a and the second port 6b communicate with each other, and in the second switching position L, the first port 6a and the second port 6b are respectively connected to the third port 6c. Alternatively, since the fourth port 6d communicates with the inside, the above effect can be stably exhibited.

  In particular, since the flow control valve is the needle valve 5, the frictional resistance with the compressed air can be kept small during the valve opening, and the load when the valve is closed can be reduced.

  Further, the parts feeder 2 of the present invention injects compressed air from the air supply / discharge path 21 that is supplied and exhausted by the air on / off circuit 1 of the present embodiment, and is defective among the workpieces W conveyed on the conveyance path 20. Since the defective workpiece processing means 22 is provided as an ejected mechanism for removing the object from the conveying path 20 or changing the posture on the conveying path 20, it is possible to quickly inject compressed air having the same pressure from the defective workpiece processing means 22 each time. Since the responsiveness of the compressed air is fast, even when the miniaturized workpiece W is conveyed on the conveyance path 20 at a high speed, the time during which the compressed air is blown to each workpiece 20 is shortened and adjacent to each other. Without affecting other workpieces W, it is possible to remove the inappropriate workpiece W from the conveyance path 20 or reverse the posture on the conveyance path 20 to change the posture.

  As mentioned above, although one Embodiment of this invention was described, the specific structure of each part is not limited only to embodiment mentioned above.

  For example, in the present embodiment, the needle valve 5 is used as the flow control valve. However, the present invention is not limited to this, and a proportional valve or a needle valve with a check valve (speed controller) may be used as the flow control valve. Since the flow control valve is a proportional valve, it is possible to digitally control the opening and closing of the valve instead of manually. Further, since the flow control valve is arranged on the input side of the 4-port valve 6, even if a needle valve with a check valve is used as the flow control valve at a pressure lower than the minimum operating pressure, it can be used suitably.

  In this embodiment, the 4-port valve 6 is used as the direction switching valve. However, the present invention is not limited to this, and a switching valve having a 5-port valve or more ports may be used. In addition, a piezoelectric valve may be used instead of the electromagnetic valve.

  Furthermore, the air on / off circuit 1 of the present embodiment is applied to the parts feeder 2 having the defective workpiece processing means 22 as the injection target mechanism, but is not limited to this, and is applied to an appearance inspection machine, a measurement sorting machine, and a taping machine. May be applied.

  Other configurations can be variously modified without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Air on-off circuit 2 ... Parts feeder 5 ... Needle valve (flow control valve)
6 ... 4 port valve (Direction switching valve)
6a ... 1st port 6b ... 2nd port 6c ... 3rd port 6d ... 4th port 20 ... Conveyance path 21 ... Air supply / discharge path 22 ... Defective work processing means (Injected mechanism)
W: Work R: First switching position L: Second switching position

Claims (5)

An air on / off circuit for supplying and exhausting compressed air to an injection mechanism having an air supply / discharge path,
A flow control valve for adjusting the flow rate of the compressed air;
A direction switching valve disposed downstream of the flow control valve,
The direction switching valve is
A first switching position for connecting the outlet of the flow control valve and the air supply / discharge path of the injected mechanism; and a second switching position for opening the outlet of the flow control valve and the air supply / discharge path of the injected mechanism to the atmosphere. An air on / off circuit configured to be switchable to a switching position.   The direction switching valve includes at least a first port that communicates with an outlet of the flow control valve, a second port that communicates with an air supply / discharge path of the injection target mechanism, and a third port and a fourth port that communicate with an atmospheric region. The first port and the second port communicate with each other at the first switching position, and the first port and the second port communicate with the third port or the fourth port at the second switching position, respectively. The air-on / off circuit according to claim 1, wherein the switching valve has four or more ports.   3. The air on / off circuit according to claim 1, wherein the flow control valve is a needle valve.   The air-on / off circuit according to claim 1, wherein the flow control valve is a proportional valve.   Using the air supply / exhaust path supplied and exhausted by the air on / off circuit according to any one of claims 1 to 4, defective work out of the workpieces conveyed on the conveyance path is excluded from the conveyance path or the conveyance A parts feeder comprising the jetting mechanism that changes its posture on a road.

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