JP5086771B2 - Air supply / exhaust control device in workpiece adsorption transfer system - Google Patents

Description

  The present invention relates to a supply / exhaust control device in a work adsorption transfer system including a small and light electric air pump.

  In general, for example, in a production line in an automobile manufacturing factory, a workpiece suction transfer system using a vacuum pump and a suction pad is adopted as a means for transferring a workpiece having a smooth surface such as an automobile window glass in the factory. ing. This is because, as shown in FIG. 4, the main conduit g extended from a large vacuum pump b in the factory is branched into a plurality of branch conduits i to reach each production line. Are connected to the suction pads h via the exhaust solenoid valve d of the valve unit f, and the air supply conduits j extending from the vacuum breaking electromagnetic valve e of the valve unit f are connected to the suction pads h, respectively. On the other hand, the control unit c connected to the power source a is configured to control the switching operation of the exhaust solenoid valve d and the vacuum break solenoid valve e.

  When transferring the workpiece w, the suction surface of the suction pad h is directed to the smooth surface of the workpiece w, while the air supply passage in the vacuum breaking electromagnetic valve e is shut off, and the exhaust electromagnetic valve d is opened. The suction passage is connected to the suction pad h, and the vacuum pump b sucks the air in the suction pad h to make it in a vacuum state. The vacuum passage in the suction pad h is broken by supplying the atmosphere into the suction pad h with the suction passage in d closed and the air supply passage in the vacuum break solenoid valve e in communication. The work w is released. Thus, the workpiece w can be quickly held and transferred to a desired location without damaging the surface of the workpiece w.

  By the way, in the workpiece suction transfer system configured as described above, when the vacuum in the suction pad h is broken after the workpiece w is transferred, the atmosphere is supplied into the suction pad h. There was a problem that time was slow and quick release operation could not be obtained. In addition, in order to speed up the work release operation by the suction pad h, a configuration is also known in which compressed air can be supplied into each suction pad h. Large-scale equipment such as a compressor, a large surge tank capable of storing a large amount of compressed air supplied to each suction pad h, and an air supply pipe for supplying compressed air from the surge tank to each suction pad h Is required separately. For this reason, capital investment is expensive, and installation space for large surge tanks and compressors and installation space for compressed air supply conduits are required, and maintenance and maintenance of the supply conduits is costly and labor-intensive. There was a problem of hanging.

  On the other hand, the applicant of the present application has previously proposed a small and light vacuum pump that can be directly attached to each suction pad h and vacuumed (see Japanese Patent Application No. 2006-243734). If such a vacuum pump is used, there is an advantage that a large vacuum pump b, a main conduit g, a plurality of branch conduits i, and the like in the conventional workpiece suction transfer system can be eliminated. In order to avoid the above-described problems in supplying compressed air from the large surge tank as described above to each suction pad h, the vacuum break in the suction pad h is the same as in the prior art. In addition, the air is supplied into the suction pad h. For this reason, a problem to be solved remains in that the work release time is slow and a quick release operation cannot be obtained.

  The present invention has been made in view of such a situation, and the suction pad can be vacuum-sucked by a small and lightweight electric air pump attached to each suction pad, and compressed air generated by the electric air pump can be used. It is an object of the present invention to provide a supply / exhaust control device in a work suction transfer system that can achieve speeding up of a work release operation by a suction pad by supplying a vacuum to the suction pad.

  In the present invention, the air in the suction pad is sucked to be in a vacuum state so that the workpiece is vacuum-sucked and transferred to the suction pad, and after the transfer, air is supplied into the suction pad to In a workpiece adsorption transfer system that breaks the vacuum state and releases the workpiece, an electric air pump that sucks air from the intake port by driving and discharges it from the exhaust port, and is connected to the intake port and the intake port of the electric air pump. The suction pad is disposed between the suction pad and communicates with the intake port to suck the air inside the suction pad, and sucks the outside air with the suction port connected to the outside air. A first solenoid valve selectively switched to an outside air suction state, an air storage tank connected to the exhaust port of the electric air pump, the air storage tank and the air storage tank A non-air supply state in which the supply of air from the air storage tank to the suction pad is blocked and the compressed air is stored in the air storage tank, and the inside of the air storage tank is in the suction pad. A second solenoid valve that is selectively switched to an air supply state that supplies compressed air stored in the air storage tank to the suction pad and an operation signal by detecting a predetermined degree of vacuum in the suction pad. A vacuum switch to be sent, and a switching operation of the first electromagnetic valve based on an operation signal sent from the vacuum switch. When the degree of vacuum in the suction pad is less than a predetermined degree of vacuum, the first solenoid valve And a control device for switching the first solenoid valve to the outside air suction state when the vacuum level in the suction pad reaches a predetermined vacuum level. A supply and exhaust control device in beam.

  In this configuration, the control device sets the first electromagnetic valve to the inside air suction state and the second electromagnetic valve to the non-air supply state when driving the workpiece, drives the electric air pump to electrically drive the air in the suction pad. By sucking with an air pump and making a vacuum state, the work is vacuum-sucked by the suction pad. Moreover, the air in the suction pad sucked by the electric air pump is sequentially discharged from the exhaust port and stored in the air storage tank. When the degree of vacuum in the suction pad reaches a predetermined degree of vacuum at which the workpiece can be sufficiently sucked and transferred, an operation signal is sent from the vacuum switch that has detected this, and the control device that has received the operation signal The first solenoid valve is switched to the outside air suction state. By switching the first solenoid valve to the outside air suction state, the port in the first solenoid valve communicating with the suction pad is closed by the spool, so that the reverse flow of air into the suction pad is blocked and the suction pad While the internal vacuum is maintained, the electric air pump sucks air as outside air from the first solenoid valve switched to the outside air suction state, and the air is sequentially discharged from the exhaust port into the air storage tank. Stored. Thereby, high pressure compressed air more than the air quantity attracted | sucked from the inside of an adsorption pad will be stored in an air storage tank. Thus, while storing high-pressure compressed air in the air storage tank, the workpiece can be vacuum-adsorbed and transferred to the suction pad, and after the transfer, the second electromagnetic valve is switched to the air supply state. The high pressure compressed air in the air storage tank is supplied into the suction pad, the vacuum in the suction pad is immediately broken and the workpiece is released.

  In the air supply / exhaust control device in the work adsorption transfer system, between the exhaust port of the electric air pump and the air storage tank, the exhaust port communicates with the outside air, and the air discharged from the exhaust port is discharged into the outside air. A third electromagnetic valve that is selectively switched between a discharge state and a storage state in which the exhaust port communicates with the air storage tank and the air discharged from the exhaust port is stored in the air storage tank, The switching operation of the third electromagnetic valve is controlled by the control device based on the operation signal sent from the vacuum switch, and when the degree of vacuum in the suction pad is less than the predetermined degree of vacuum, the third electromagnetic valve is in the release state. A configuration is proposed in which the third electromagnetic valve is switched to the storage state when the vacuum level in the suction pad reaches a predetermined vacuum level.

  In this configuration, the control device drives the electric air pump with the first solenoid valve in the inside air suction state, the third solenoid valve in the release state, and the second solenoid valve in the non-air supply state when the workpiece is attracted. Then, the air in the suction pad is sucked by an electric air pump to be in a vacuum state, so that the work is vacuum-sucked by the suction pad. Further, the air in the suction pad sucked by the electric air pump and discharged from the exhaust port is sequentially released into the outside air from the released third electromagnetic valve. Thereby, since no load is applied to the air discharged from the exhaust port, the suction capability of the electric air pump can be sufficiently exerted, and the degree of vacuum in the suction pad can be increased smoothly. When the degree of vacuum in the suction pad reaches a predetermined degree of vacuum at which the workpiece can be sufficiently sucked and transferred, an operation signal is sent from the vacuum switch that has detected this, and the control device that has received the operation signal The first solenoid valve is switched to the outside air suction state, and the third solenoid valve is switched to the storage state in which air is stored in the air storage tank. By switching the first solenoid valve to the outside air suction state, the port in the first solenoid valve communicating with the suction pad is closed by the spool, so that the reverse flow of air into the suction pad is blocked and the suction pad While the internal vacuum is maintained, the electric air pump draws air as outside air from the first solenoid valve switched to the outside air suction state, and the air discharged from the exhaust port is switched to the storage state. The water is sequentially stored in the air storage tank through the third electromagnetic valve. Thereby, a sufficient amount of air taken from outside air is sent into the air storage tank, and high-pressure compressed air is stored. Thus, while storing high-pressure compressed air in the air storage tank, the workpiece can be vacuum-adsorbed and transferred to the suction pad, and after the transfer, the second electromagnetic valve is switched to the air supply state. The high pressure compressed air in the air storage tank is supplied into the suction pad, the vacuum in the suction pad is immediately broken and the workpiece is released.

  Further, in the air supply / exhaust control device in the work adsorption transfer system, a predetermined pressure of the compressed air stored in the air storage tank is detected, and an operation signal that triggers to stop driving the electric air pump is sent out. A configuration with a pressure switch is proposed. In such a configuration, when the compressed air stored in the air storage tank reaches a predetermined pressure, the control device can stop the driving of the electric air pump based on the operation signal sent from the pressure switch. Further, generation and storage of compressed air exceeding the necessary amount can be prevented, and wasteful consumption of electric power by the electric air pump can be suppressed.

  As described above, the present invention includes an electric air pump that sucks air from the intake port by driving and discharges the air from the exhaust port, and the suction pad connected to the intake port and the suction pad connected to the intake port. The suction pad is communicated with the intake port to selectively suck in the air inside the suction pad, and the outside air suction state in which the suction port communicates with the outside air and sucks outside air. A first solenoid valve that is switched to the air storage tank, an air storage tank connected to the exhaust port of the electric air pump, and the air storage tank and the suction pad connected to the air storage tank. The air supply from the storage tank to the suction pad is shut off and the compressed air is stored in the air storage tank, and the air storage tank is communicated with the suction pad and stored in the air storage tank. Compressed air A second electromagnetic valve selectively switched to an air supply state to be supplied to the landing pad, a vacuum switch for detecting a predetermined degree of vacuum in the suction pad and sending an operation signal, and an operation signal sent from the vacuum switch Based on the control, the switching operation of the first electromagnetic valve is controlled, and when the vacuum level in the suction pad is less than a predetermined vacuum level, the first electromagnetic valve is switched to the inside air suction state, and the vacuum level in the suction pad is set to a predetermined level. Since it is a supply / exhaust control device in a work suction transfer system having a control device that switches the first solenoid valve to the outside air suction state when the degree of vacuum is reached, an electric air pump to which the suction pad is connected Vacuum suction can be performed, and when the suction pad reaches a predetermined degree of vacuum, the control device is based on an operation signal sent from a vacuum switch that detects this. There switches the first solenoid valve to the outside air suction state, by sucking the air as the outside air, it is possible to store the compressed air of the air amount or more of the high pressure which is sucked from the suction pad to the air storage tank. And, if necessary, switch the second solenoid valve to the air supply state, supply the high pressure compressed air of the air storage tank to the suction pad and perform vacuum break, compared to the case of supplying the atmosphere, The takt time for releasing the workpiece is increased, and the workpiece releasing operation can be speeded up.

  In addition, a small and lightweight electric air pump can be used as the electric air pump, and each of the suction pads can be vacuum-sucked using such a small and lightweight electric air pump. In order to supply compressed air from the surge tank to each suction pad, and a large-sized surge tank capable of storing a large amount of compressed air to be supplied to each suction pad, as well as a conventional compressor Large-scale equipment such as air supply piping is not required. As a result, the capital investment is small, and the installation space for large surge tanks and compressors and the space for installing compressed air supply conduits are not required, and the maintenance and maintenance costs for the supply conduits are reduced. It can be unnecessary.

  Further, in the supply / exhaust control device in the work adsorption transfer system, the air discharged from the exhaust port is communicated between the exhaust port of the electric air pump and the air storage tank. A third solenoid valve is provided that can be selectively switched between a discharge state in which the air is discharged and a storage state in which the exhaust port communicates with the air storage tank and the air discharged from the exhaust port is stored in the air storage tank. The switching operation of the third electromagnetic valve is controlled by the control device based on the operation signal sent from the vacuum switch, and the third electromagnetic valve is released when the vacuum degree in the suction pad is less than the predetermined vacuum degree. If the third solenoid valve is switched to the storage state when the vacuum level in the suction pad reaches a predetermined vacuum level, the third solenoid valve is released during vacuum suction in the suction pad. By being switched to a state, the air in the suction pad is sucked into the electric air pump is discharged from the exhaust port can be sequentially discharged into the ambient air from the third solenoid valve release state. Thereby, since no load is applied to the air discharged from the exhaust port, the suction capability of the electric air pump can be sufficiently exerted, and the degree of vacuum in the suction pad can be increased smoothly. Further, when the inside of the suction pad reaches a predetermined degree of vacuum, the control device switches the first electromagnetic valve to the outside air suction state based on an operation signal sent from a vacuum switch that detects this, and sucks air as outside air. At the same time, the third electromagnetic valve is switched to the storage state to store air in the air storage tank. Thereby, a sufficient amount of air taken in from the outside air is sent into the air storage tank, and high-pressure compressed air can be stored.

  Furthermore, in the air supply / exhaust control device in the work adsorption transfer system, a predetermined pressure of the compressed air stored in the air storage tank is detected, and an operation signal that triggers to stop driving the electric air pump is sent out. In the configuration equipped with a pressure switch, when the compressed air stored in the air storage tank reaches a predetermined pressure, the control device stops driving the electric air pump based on an operation signal sent from the pressure switch. Therefore, it is possible to prevent generation and storage of compressed air more than the necessary amount, and to suppress wasteful consumption of electric power by the electric air pump.

  Below, the 1st Example of the air supply / exhaust control apparatus in the workpiece | work adsorption | suction transfer system concerning this invention is described based on FIG. 1, FIG.

  First, a small and lightweight electric air pump that can be suitably used in the present invention will be described. For convenience of explanation, the left and right direction and the up and down direction of the electric air pump are determined by the illustrated positional relationship, but the electric air pump can be used in various directions, and the left and right direction and the up and down direction are not necessarily limited to the following. It is not something.

  FIG. 1 shows an example of an electric air pump 1 that draws air from an intake port 2 and discharges it from an exhaust port 3 by driving. The electric air pump 1 includes a vertical piston chamber 5 in a pump housing 4. The piston 6 is fitted in the piston chamber 5 so as to be able to advance and retract. A crank member 7 is rotatably supported on the upper portion of the pump housing 4 by a pair of left and right bearings 8, 8, and the crank member 7 is driven to rotate by an electric motor 9. And the eccentric shaft part 10 provided in the crank member 7 and the piston pin 11 provided in the said piston 6 are connected by the connection link member 12, and when the electric motor 9 drives and the crank member 7 rotates, The connecting link member 12 swings in the vertical direction through the eccentric rotating action of the eccentric shaft portion 10, and the piston 6 connected to the lower portion of the connecting link member 12 is driven to advance and retreat in the vertical direction in the piston chamber 5. It is like that.

  In addition, an intake passage 13 and an exhaust passage 14 are formed in a lower portion in the pump housing 4 so as to be separated from each other. The intake passage 13 and the exhaust passage 14 are separated from the piston chamber 5 by a partition member 15. Has been. The outer end of the intake passage 13 that opens to one side surface of the pump housing 4 serves as the intake port 2, and the outer end of the exhaust passage 14 that opens to the other side surface of the pump housing 4 serves as the exhaust port 3. Yes.

  A plurality of intake holes 16 are formed in the partition member 15 at a portion corresponding to the inner end of the intake passage 13, and the chamber end of the piston chamber 5 positioned on the advance side of the piston 6 by the intake holes 16, The intake passage 13 is in communication. The partition member 15 is provided with a first check valve 17 including an umbrella valve that opens and closes the intake hole 16 to allow only air flow from the intake passage 13 to the piston chamber 5.

  A plurality of exhaust holes 18 are formed in the partition member 15 at a portion corresponding to the inner end of the exhaust passage 14, and the chamber of the piston chamber 5 located on the advance side of the piston 6 by the exhaust holes 18. The end and the exhaust path 14 communicate with each other. Further, the partition member 15 is provided with a second check valve 19 including an umbrella valve that opens and closes the exhaust hole 18 to allow only air flow from the piston chamber 5 to the exhaust passage 14.

  In the electric air pump 1 having such a configuration, when the crank member 7 is rotated by energization of the electric motor 9 and the piston 6 is continuously advanced and retracted, the piston chamber 5 located on the advancing side of the piston 6 Expansion and contraction of the lower variable volume 37 are repeated. Here, when the piston 6 moves backward and the variable volume 37 of the piston chamber 5 is expanded, the inside of the variable volume 37 becomes lower than the intake passage 13, and the differential pressure causes the first check valve 17 to move. An opening operation in which the umbrella-shaped valve membrane portion 20 is elastically deformed upward occurs, the intake hole 16 is opened, air is sucked from the intake port 2 and flows into the variable volume 37 of the piston chamber 5. At this time, the second check valve 19 is maintained in a closed state by a differential pressure with respect to the variable volume 37 of the piston chamber 5, which is at a lower pressure than in the exhaust passage 14. Next, when the piston 6 moves forward and the variable volume 37 of the piston chamber 5 is reduced, the inside of the variable volume 37 becomes a higher pressure than that in the intake passage 13, and the first reverse that has been elastically deformed upward until then. The intake hole 16 is closed by the closing operation in which the umbrella-shaped valve membrane portion 20 of the stop valve 17 returns to its former position through its elastic restoring force, the backflow of air to the intake passage 13 is blocked, and the air is compressed. The When the air is squeezed in this way and the exhaust passage 14 has a lower pressure than the variable volume 37 of the piston chamber 5, the umbrella-shaped valve membrane portion 21 of the second check valve 19 is caused by the differential pressure. An opening operation that elastically deforms downward occurs, the exhaust hole 18 is opened, and the compressed air in the variable volume 37 of the piston chamber 5 is discharged from the exhaust port 3 through the exhaust passage 14.

  As described above, the electric air pump 1 is configured to release the air from the intake port 2 by the opening operation of the first check valve 17 and the closing operation of the second check valve 19 which are generated when the variable volume 37 of the piston chamber 5 is expanded. While the suction action is obtained, the discharge action of the compressed air from the exhaust port 3 by the closing action of the first check valve 17 and the opening action of the second check valve 19 which occur as the variable volume 37 of the piston chamber 5 is reduced. Can be obtained.

  Such an electric air pump 1 can be manufactured with outer dimensions of a lateral width of 130 mm, a height of 115 mm, and a depth of about 47 mm, and is extremely small and light compared to a general electric air pump. The electric air pump 1 used in the present invention is not limited to the above-described configuration, and any other configuration can be used as long as it is a small and lightweight one that can obtain a predetermined air suction action and compressed air discharge action. It may be.

Next, the main part of the present invention will be described.
As shown in FIG. 2, a suction pad 23 is connected to the intake port 2 of the electric air pump 1 through a first electromagnetic valve 22. The first electromagnetic valve 22 is a two-position three-port switching valve, and in the normal position by spring energization, the suction pad 23 communicates with the intake port 2 of the electric air pump 1 so that the air in the suction pad 23 is discharged. The inside air sucking state for sucking and the outside air sucking state for sucking outside air by communicating the intake port 2 with outside air at an offset position by energizing the solenoid are selectively switched. The air flow path from the suction pad 23 to the first electromagnetic valve 22 is provided with a vacuum switch 24 that detects the degree of vacuum in the suction pad 23 and sends an operation signal when the degree of vacuum in the suction pad 23 reaches a predetermined level. The communication cable 25 extended from the vacuum switch 24 is connected to the control device 26. The control device 26 has a control content for controlling the switching operation of the first electromagnetic valve 22 based on the operation signal sent from the vacuum switch 24, and the degree of vacuum in the suction pad 23 is less than a predetermined degree of vacuum. In this case, the first electromagnetic valve 22 is switched to the inside air suction state, and when the vacuum degree in the suction pad 23 reaches a predetermined vacuum degree, the solenoid is energized to switch the first electromagnetic valve 22 to the outside air suction state. . The solenoid of the first electromagnetic valve 22 is connected to an electric wire 27 through which the control device 26 supplies an operating current.

  An air storage tank 28 is connected to the exhaust port 3 of the electric air pump 1, and the air storage tank 28 is connected to the suction pad 23 via a second electromagnetic valve 29. The second solenoid valve 29 is a two-position two-port switching valve, and is in a normal position by a spring bias, shuts off the supply of air from the air storage tank 28 to the suction pad 23 and squeezes air into the air storage tank 28. The compressed air stored in the air storage tank 28 is supplied to the suction pad 23 by communicating the inside of the air storage tank 28 with the suction pad 23 in the non-air supply state in which the air is stored and the offset position by energizing the solenoid. It can be selectively switched to an air supply state. The solenoid of the second electromagnetic valve 29 is connected to an electric wire 30 through which the control device 26 supplies an operating current.

  Further, the air storage tank 28 or an air flow path in the vicinity thereof is provided with a pressure switch 32 for detecting the compressed air stored in the air storage tank 28 and sending an operation signal when the compressed air is at a predetermined pressure. A communication cable 33 extending from the pressure switch 32 is connected to the control device 26. The control device 26 has a control content for controlling energization / non-energization to the electric motor 9 (see FIG. 1) of the electric air pump 1 based on an operation signal sent from the pressure switch 32, and an air storage tank. When the compressed air in 28 reaches a predetermined pressure, energization of the electric motor 9 is stopped. The control device 26 and the electric air pump 1 are connected by an electric wire 34 that supplies a drive current to the electric motor 9. A regulator 31 is disposed between the air storage tank 28 and the second electromagnetic valve 29 so that the pressure of the compressed air supplied to the suction pad 23 by the regulator 31 is always constant. Yes.

  In such a configuration, when the workpiece w is attracted, the first electromagnetic valve 22 and the second electromagnetic valve 29 are each held in the normal position by the spring bias under the control of the control device 26. That is, the first electromagnetic valve 22 is in the inside air suction state, and the second electromagnetic valve 29 is in the non-air supply state. In this state, when the electric air pump 1 is driven by energizing the electric motor 9 (see FIG. 1), the air in the suction pad 23 is sequentially sucked from the intake port 2 of the electric air pump 1 and thereby the suction pad 23. The inside becomes a vacuum state, and the work w is vacuum-sucked to the suction pad 23. The air in the suction pad 23 sucked by the electric air pump 1 is sequentially discharged from the exhaust port 3 and stored in the air storage tank 28. When the degree of vacuum in the suction pad 23 reaches a predetermined degree of vacuum at which the workpiece w can be sufficiently sucked and transferred, an operation signal is sent from the vacuum switch 24 that detects this. When this operation signal is received, the control device 26 applies an operating current to the solenoid of the first electromagnetic valve 22 to bring it into an excited state, whereby the first electromagnetic valve 22 is switched to the outside air suction state. By the switching operation of the first electromagnetic valve 22 to the outside air suction state, the port in the first electromagnetic valve 22 communicating with the suction pad 23 is closed by the spool, so that the backflow of air into the suction pad 23 is blocked. While the vacuum degree in the suction pad 23 is maintained, air as the outside air is sucked into the electric air pump 1 from the first electromagnetic valve 22 switched to the outside air suction state, and the air is sequentially supplied from the exhaust port 3. It is discharged and stored in the air storage tank 28. As a result, high-pressure compressed air that is equal to or greater than the amount of air sucked from the suction pad 23 is stored in the air storage tank 28. Here, when the compressed air in the air storage tank 28 reaches a predetermined pressure, an operation signal is sent out from the pressure switch 32 that detects this, and the control device 26 energizes the electric motor 9 based on the operation signal. Is stopped and driving of the electric air pump 1 is stopped. Thereby, generation | occurrence | production and storage of compressed air more than required amount are prevented, and the useless consumption of the electric power by the electric air pump 1 can be suppressed. Thus, while storing high-pressure compressed air in the air storage tank 28, the workpiece w can be vacuum-adsorbed and transferred to the suction pad 23, and after the transfer, the solenoid to the solenoid of the second electromagnetic valve 29 can be transferred. By switching the second electromagnetic valve 29 to the air supply state by energization, the high-pressure compressed air in the air storage tank 28 is supplied into the suction pad 23, and the vacuum in the suction pad 23 is immediately broken. Work w is released.

  As described above, when the compressed air in the air storage tank 28 is supplied into the suction pad 23, the inside of the suction pad 23 becomes less than a predetermined degree of vacuum, so that the control device 26 based on the detection of the vacuum switch 24 is used. As a result of this control, the energization of the solenoid of the first electromagnetic valve 22 is released, and the first electromagnetic valve 22 is switched to the normal air suction state at the normal position by the biasing of the spring. Further, since the pressure in the air storage tank 28 decreases, the electric motor 9 can be energized by the control of the control device 26 based on the detection of the pressure switch 32.

  Thus, according to the configuration of the first embodiment, vacuum suction of the suction pad 23 can be performed by the electric air pump 1 to which the suction pad 23 is connected, and when the inside of the suction pad 23 reaches a predetermined degree of vacuum, Based on the operation signal sent from the vacuum switch 24 that detects this, the control device 26 switches the first electromagnetic valve 22 to the outside air suction state and sucks air as outside air, so that it is sucked from the inside of the suction pad 23. High pressure compressed air that is equal to or greater than the amount of air to be stored can be stored in the air storage tank 28. Then, the second electromagnetic valve 29 is switched to an air supply state as necessary, and the high pressure compressed air of the air storage tank 28 is supplied to the suction pad 23 to perform vacuum break, thereby comparing with the case of supplying the atmosphere. As a result, the tact time of the work release becomes faster, and the work release operation can be speeded up.

  The electric air pump 1 can be a small and light electric air pump. The small and light electric air pump 1 can be used for vacuum suction of each suction pad 23 and can be used for vacuum breakage. The high-pressure compressed air can be generated, and a conventional compressor, a large surge tank capable of storing a large amount of compressed air to be supplied to each suction pad 23, and the suction pad 23 being compressed from the surge tank to each suction pad 23 Large-scale equipment such as an air supply pipe for supplying air becomes unnecessary. As a result, the capital investment is small, and the installation space for large surge tanks and compressors and the space for installing compressed air supply conduits are not required, and the maintenance and maintenance costs for the supply conduits are reduced. It can be unnecessary.

  FIG. 3 shows a second embodiment. In the second embodiment, in addition to the configuration of the first embodiment described above, the third embodiment is provided between the exhaust port 3 of the electric air pump 1 and the air storage tank 28. An electromagnetic valve 35 is provided. The third solenoid valve 35 is a two-position / three-port switching valve, and is a normal position that is biased by a spring, and releases the air discharged from the exhaust port 3 into the outside air by communicating the exhaust port 3 with the outside air. And a storage state in which the exhaust port 3 communicates with the air storage tank 28 and the air discharged from the exhaust port 3 is stored in the air storage tank 28 at an offset position by energizing the solenoid. It is supposed to be.

  Further, the control device 26 has a control content for controlling the switching operation of the third electromagnetic valve 35 based on an operation signal sent from the vacuum switch 24, and the degree of vacuum in the suction pad 23 is less than a predetermined degree of vacuum. In this case, the third electromagnetic valve 35 is switched to the release state, and when the vacuum level in the suction pad 23 reaches a predetermined vacuum level, the solenoid is energized to switch the third electromagnetic valve 35 to the storage state. The solenoid of the third electromagnetic valve 35 is connected to an electric wire 36 through which the control device 26 supplies an operating current.

  In this configuration, when the workpiece w is attracted, the first electromagnetic valve 22, the second electromagnetic valve 29, and the third electromagnetic valve 35 are each held in the normal position by the spring bias under the control of the control device 26. That is, the first electromagnetic valve 22 is in the inside air suction state, the second electromagnetic valve 29 is in the non-air supply state, and the third electromagnetic valve 35 is in the discharge state. In this state, when the electric air pump 1 is driven by energizing the electric motor 9 (see FIG. 1), the air in the suction pad 23 is sequentially sucked from the intake port 2 of the electric air pump 1 and thereby the suction pad 23. The inside becomes a vacuum state, and the work w is vacuum-sucked to the suction pad 23. Further, the air in the suction pad 23 sucked by the electric air pump 1 and discharged from the exhaust port 3 is sequentially released from the released third electromagnetic valve 35 into the outside air. Thereby, since no load is applied to the air discharged from the exhaust port 3, the suction capability of the electric air pump 1 can be sufficiently exerted, and the degree of vacuum in the suction pad 23 can be increased smoothly. When the degree of vacuum in the suction pad 23 reaches a predetermined degree of vacuum at which the workpiece w can be sufficiently sucked and transferred, an operation signal is sent from the vacuum switch 24 that detects this. Upon receiving this operation signal, the control device 26 applies an operating current to the solenoid of the first solenoid valve 22 to bring it into an excited state, whereby the first solenoid valve 22 is switched to the outside air suction state and the third solenoid valve. By energizing the solenoid 35 with an operating current to an excited state, the third solenoid valve 35 is switched to a storage state in which air is stored in the air storage tank 28. By the switching operation of the first electromagnetic valve 22 to the outside air suction state, the port in the first electromagnetic valve 22 communicating with the suction pad 23 is closed by the spool, so that the backflow of air into the suction pad 23 is blocked. While the vacuum degree in the suction pad 23 is maintained, air as outside air is sucked into the electric air pump 1 from the first electromagnetic valve 22 switched to the outside air suction state and discharged from the exhaust port 3. Air is sequentially stored in the air storage tank 28 through the third electromagnetic valve 35 switched to the storage state. Thereby, a sufficient amount of air taken in from the outside air is sent into the air storage tank 28, and high-pressure compressed air is stored. Thus, while storing high-pressure compressed air in the air storage tank 28, the workpiece w can be vacuum-adsorbed and transferred to the suction pad 23, and after the transfer, the solenoid to the solenoid of the second electromagnetic valve 29 can be transferred. By switching the second electromagnetic valve 29 to the air supply state by energization, the high-pressure compressed air in the air storage tank 28 is supplied into the suction pad 23, and the vacuum in the suction pad 23 is immediately broken. Work w is released.

  As described above, when the compressed air in the air storage tank 28 is supplied into the suction pad 23, the inside of the suction pad 23 becomes less than a predetermined degree of vacuum, so that the control device 26 based on the detection of the vacuum switch 24 is used. As a result of the control, the energization of each solenoid of the first solenoid valve 22 and the third solenoid valve 35 is released, the first solenoid valve 22 is switched to the normal air suction state at the normal position by the spring bias, and the third solenoid valve 35 is a spring. The discharge state of the normal position is switched by energization.

  As described above, according to the configuration of the second embodiment, the third electromagnetic valve 35 is switched to the release state during vacuum suction in the suction pad 23, thereby being sucked into the electric air pump 1 and discharged from the exhaust port 3. The air in the suction pad 23 can be sequentially released into the outside air from the released third electromagnetic valve 35. Thereby, since no load is applied to the air discharged from the exhaust port 3, the suction capability of the electric air pump 1 can be sufficiently exerted, and the degree of vacuum in the suction pad 23 can be increased smoothly. Further, when the inside of the suction pad 23 reaches a predetermined degree of vacuum, the control device 26 switches the first electromagnetic valve 22 to the outside air suction state based on the operation signal sent from the vacuum switch 24 that detects this, and the outside air is The air is sucked and the third electromagnetic valve 35 is switched to the storage state so that the air discharged from the exhaust port 3 is stored in the air storage tank 28. A large amount of air is sent in and high-pressure compressed air can be stored.

It is a vertical front view of the electric air pump 1. It is a schematic diagram which shows the air supply / exhaust control apparatus in the workpiece | work adsorption | suction transfer system concerning a 1st Example. It is a schematic diagram which shows the air supply / exhaust control apparatus in the workpiece | work adsorption | suction transfer system concerning a 2nd Example. It is the schematic of the workpiece | work adsorption | suction transfer system of a conventional structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric air pump 2 Intake port 3 Exhaust port 22 First electromagnetic valve 23 Suction pad 24 Vacuum switch 26 Control device 28 Air storage tank 29 Second electromagnetic valve 32 Pressure switch 35 Third electromagnetic valve w Workpiece

Claims (2)

By sucking the air in the suction pad and making it in a vacuum state, the workpiece is vacuum-sucked and transferred to the suction pad, and after the transfer, air is supplied into the suction pad to destroy the vacuum state in the suction pad. In the workpiece adsorption transfer system that releases the workpiece,
An electric air pump that draws air from the intake port and discharges it from the exhaust port by driving;
An inside air suction state that is disposed between the suction port of the electric air pump and a suction pad connected to the suction port and communicates the inside of the suction pad with the suction port to suck the air in the suction pad; A first solenoid valve that is selectively switched to an outside air suction state in which the intake port communicates with outside air and sucks outside air;
An air storage tank connected to the exhaust port of the electric air pump;
It is disposed between the air storage tank and the suction pad connected to the air storage tank, and shuts off the supply of air from the air storage tank to the suction pad and stores compressed air in the air storage tank. A second solenoid valve that is selectively switched between an air supply state and an air supply state in which compressed air stored in the air storage tank is connected to the suction pad by communicating with the inside of the air storage tank.
A vacuum switch for detecting a predetermined degree of vacuum in the suction pad and sending an operation signal;
Based on the operation signal sent from the vacuum switch, the switching operation of the first electromagnetic valve is controlled, and when the degree of vacuum in the suction pad is less than a predetermined degree of vacuum, the first electromagnetic valve is switched to the inside air suction state. A control device that switches the first solenoid valve to an outside air suction state when the degree of vacuum in the suction pad reaches a predetermined degree of vacuum;
Further, between the exhaust port of the electric air pump and the air storage tank, a discharge state in which the exhaust port communicates with the outside air to release the air discharged from the exhaust port into the outside air, and the exhaust port communicates with the air storage tank. A third electromagnetic valve that is selectively switched to a storage state in which air discharged from the exhaust port is stored in an air storage tank, and the switching operation of the third electromagnetic valve is sent from the vacuum switch. When the vacuum level in the suction pad is less than the predetermined vacuum level, the third solenoid valve is switched to the release state, and the vacuum level in the suction pad is set to the predetermined vacuum level. The air supply / exhaust control device in the workpiece adsorption / transfer system , wherein the third electromagnetic valve is switched to the storage state when the pressure reaches the storage state . 2. The pressure switch according to claim 1, further comprising a pressure switch that detects a predetermined pressure of the compressed air stored in the air storage tank and sends an operation signal that triggers the drive of the electric air pump to be stopped. Air supply / exhaust control device for work adsorption transfer system.

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