JP2009108678A - Bellows pump and its driving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce operating cost by reusing compressed gas for driving within a bellows pump system. <P>SOLUTION: This bellows pump includes a pair of cylinder chambers 3R, 3L; a pair of bellows 4R, 4L arranged in the cylinder chambers 3R, 3L, respectively; a connecting member 5 for interconnecting the bellows 4R, 4L; a port switching type solenoid valve 6 enabling alternate pressure feeding of compressed gas for driving to the respective cylinder chambers 3R, 3L; and a control part 10 for controlling the solenoid valve 6. By alternately stretching/contracting the bellows 4R, 4L accompanied by reciprocation of the compressed gas and the connecting member 5, liquid is sucked to one and discharged from the other. The bellows pump is further provided with a passage (connecting pipe) 11 for interconnecting the respective cylinder chambers 3R, 3L and a valve (normally closed type solenoid valve) 12 provided on the passage 11. Compressed gas in the cylinder chamber on the high-pressure side out of the respective cylinder chambers 3R, 3L can be introduced to the cylinder chamber on the low-pressure side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention particularly relates to a bellows pump that sucks and discharges liquid by alternately expanding and contracting a pair of bellows, and a driving method thereof.

  8 and 9 show two schematic structures in which the bellows pump is simplified. The bellows pump shown in each figure has the same basic structure as that disclosed in Patent Document 1, and has a pair of cylinder chambers 3R and 3L defined by cylinder cases 1R and 1L, a pump head 2 and the like, and an opening in the pump head 2. A pair of bellows 4R, 4L respectively disposed in the corresponding cylinder chambers 3R, 3L with the end mounted, a connecting member 5 connecting the bellows 4R, 4L, and driving to each cylinder chamber 3R, 3L And a port-switching solenoid valve 6 capable of alternately feeding compressed gas, and the bellows 4R and 4L are alternately expanded and contracted with the reciprocating motion of the compressed gas and the connecting member 5 sent through the solenoid valve 6. As a result, the liquid is inhaled and discharged.

  Here, the cylinder chambers 3R, 3L are provided with sensors G, F for detecting the contraction or extension state of the bellows 4R, 4L. The detection signals of the sensors F and G are transmitted to the control unit 10 and used for controlling the electromagnetic valve 6. The solenoid valve (for example, 5 port, 2 position, single solenoid) 6 has a P port for introducing compressed gas, an E1 port and an E2 port for exhaust, and an A port connected to the cylinder chamber 3R via a pipe 7. The B port is connected to the cylinder chamber 3L via the pipe 8. Further, the structure of FIG. 9 is provided with quick exhaust valves 9 and 9 in the middle of the pipes 7 and 8 with respect to the structure of FIG. Each quick exhaust valve 9 is a check valve for rapidly exhausting the compressed gas in the corresponding cylinder chamber 3R or 3L.

  The above-described driving method of the bellows pump determines which of the cylinder chambers 3R and 3L is supplied with compressed gas when starting. Here, it shall supply from the cylinder chamber 3R. The solenoid valve 6 is energized with a solenoid when the pump is activated, so that compressed gas is supplied from the P port to the cylinder chamber 3R through the A port and the pipe 7 from the supply / discharge port C provided in the cylinder case 1R. . At this time, the compressed gas in the cylinder chamber 3L is exhausted from the supply port D of the cylinder case 1L through the pipe 8 and the B port of the electromagnetic valve 6 via the E2 port.

When the compressed gas enters the cylinder chamber 3R and the compressed gas in the cylinder chamber 3L is discharged, a pressure difference is generated between the cylinder chamber 3R and the cylinder chamber 3L, the bellows 4R is contracted, and the bellows 4L is reciprocated with the connecting member 5. Is expanded. When the bellows 4R is sufficiently contracted, the sensor F for detecting the stroke end is turned ON. When the sensor F is turned on, the solenoid valve 6 is switched by demagnetizing the solenoid via the control unit 10. This time, the compressed gas is supplied from the P port of the solenoid valve 6 to the cylinder chamber 3L through the B port and the pipe 8 from the supply / discharge port D of the cylinder case 1L. At this time, the compressed gas in the cylinder chamber 3R is exhausted from the supply / discharge port C of the cylinder case 1R through the pipe 7 and the A port of the electromagnetic valve 6 via the E1 port. When the compressed gas enters the cylinder chamber 3L and the compressed gas in the cylinder chamber 3R is discharged, a pressure difference is generated between the cylinder chamber 3R and the cylinder chamber 3L, the bellows 4L is contracted, and the bellows 4R is expanded via the connecting member 5. The When the bellows 4L is sufficiently contracted, the sensor G is turned on. When the sensor G is turned ON, the solenoid valve 6 is switched by exciting the solenoid via the control unit 10 and the above operation is repeated. The thing of patent documents 1 makes it possible to detect the fine breakage of a bellows in the above bellows pump.
JP-A-10-323607

  In the bellows pump and the driving method thereof, the compressed gas exhausted from the E2 port and the E1 port of the electromagnetic valve 6 is generally released to the atmosphere without being recovered. In the structure of FIG. 9, the supply air is the same as in FIG. 8, but the exhaust is mostly performed from the port H <b> 1 and the port H <b> 2 of the quick exhaust valve 9. This exhausted compressed gas is also released into the atmosphere without being recovered. That is, conventionally, the compressed gas for driving is air, nitrogen, etc., and since these are recovered and released into the atmosphere without being reused, the amount of compressed gas used increases, resulting in increased costs and energy. There was a problem from an environmental point of view that the efficiency was low and the generation of carbon dioxide was suppressed.

  An object of the present invention is to reduce operating costs by reusing part of the compressed gas for driving in the bellows pump system, and at the same time, to indirectly contribute to the reduction of carbon dioxide. .

  In order to achieve the above object, the invention of claim 1 is directed to a pair of cylinder chambers, a pair of bellows disposed in each cylinder chamber, a connecting member connecting the bellows, and driving to each cylinder chamber. And a control unit that controls the solenoid valve, and the bellows are alternately expanded and contracted with the reciprocation of the compressed gas and the connecting member. In the bellows pump that sucks liquid into one side and discharges from the other, a passage connecting the cylinder chambers and a valve for opening and closing the passage are provided. It is characterized in that gas can flow into the low-pressure side cylinder chamber.

  On the other hand, the invention of claim 4 is directed to a pair of cylinder chambers, a pair of bellows disposed in each cylinder chamber, a connecting member connecting the bellows, and driving to each cylinder chamber. A port-switching solenoid valve that alternately supplies compressed gas, and the bellows are alternately expanded and contracted with the reciprocating motion of the compressed gas and the connecting member, thereby sucking liquid into one side and discharging it from the other. In the driving method of the bellows pump, the supply of the compressed gas to each cylinder chamber is stopped, and the valve provided in the passage connecting the cylinder chambers is switched from the closed state to the open state. Among these, the compressed gas in the high pressure side cylinder chamber in which the bellows is contracted is subjected to a process of flowing into the low pressure side cylinder chamber in which the bellows is extended.

  In each of the above inventions, air or nitrogen is generally used as the driving compressed gas, but it may be other than that. Conventionally, a port-switching solenoid valve is generally used with 5 ports and 2 positions, but 5 ports, 3 positions and a closed center (in the example of FIGS. Those in which A and B are both closed are preferred. In the case of using a 5-port, 2-position solenoid valve, the solenoid valve 6 side and the second pipe from the connecting portion of the first pipe 7 between the connecting pipe 11 and the first pipe 7 in the structure of FIG. 8, a valve for opening and closing a pipe such as a solenoid valve is attached to the solenoid valve 6 side from a connection portion between the connection pipe 11 and the second pipe 8. In the configuration of FIG. 2, for example, a pipe opening / closing valve such as an electromagnetic valve is attached to the cylinder chamber side from each quick exhaust valve 9 in the first pipe 7 and the second pipe 8. In terms of control, before switching the valve of the present invention from the closed state to the open state, the pipe open / close valves attached to the first pipe 7 and the second pipe are simultaneously switched from the open state to the closed state. In addition, after the valve of the present invention is switched from the open state to the closed state, the pipe opening / closing valves attached to the first pipe 7 and the second pipe are simultaneously switched from the closed state to the open state. .

  In contrast, the valve of the present invention is provided in a passage connecting the cylinder chambers. For example, the port-switching solenoid valve is opened from the closed valve in a state where the supply of compressed gas to the cylinder chambers is stopped. By switching to the valve state, the compressed gas in the high-pressure side cylinder chamber in which the bellows is contracted can be allowed to flow into the low-pressure side cylinder chamber in which the bellows is extended. The valve may be of any structure or type as long as it can open and close the passage, but a normally closed solenoid valve is preferable in terms of operational characteristics and reliable and simplified control.

In each of the above inventions, it is more preferable to be embodied as follows.
First, the passage connects a first pipe connecting one of the cylinder chambers and a corresponding port of the solenoid valve, and a second pipe connecting the other of the cylinder chambers and a corresponding port of the solenoid valve. A connecting pipe connecting two pipes (Claim 2).
Second, the passage connects the first pipe connecting one of the cylinder chambers and the corresponding port of the solenoid valve, and the first pipe connecting the other port of the cylinder chamber and the corresponding port of the solenoid valve. The two pipes are connection pipes that are separately provided and connect between one and the other of the cylinder chambers (Claim 3).

  In the invention of claim 1, since the compressed gas in the high pressure side cylinder chamber can flow into the low pressure side cylinder chamber via a valve and a passage, the operating cost is reduced by reducing the total use amount and the total production amount of the driving compressed gas. And thereby improve energy efficiency.

  In the invention of claim 2, the passage configuration connecting the cylinder chambers is simple, and can be easily applied to an existing bellows pump.

  In the invention of claim 3, the passage configuration connecting the cylinder chambers is a dedicated connection pipe, and simplification is achieved by providing it integrally with the pump head in addition to the configuration of FIG.

  In the invention of claim 4, the compressed gas in the high pressure side cylinder chamber in which the bellows is contracted among the cylinder chambers in the state where the supply of the compressed gas to each cylinder chamber is stopped, the low pressure side in which the bellows extends. Since it goes through the process of flowing into the cylinder chamber, it is possible to reduce the operating cost by reducing the total amount used and the total amount of production of the compressed gas for driving, and the energy efficiency can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this description, the structure of FIG. 1, the first modification of FIG. 2, the pump driving method of the bellows pump, the second modification of FIG. 4 will be described in detail, and then an embodiment in which the present invention is actually applied will be referred to. . 1, 2, and 4, the same reference numerals are used for the same members and parts as those shown in FIGS. 8 and 9.

(Structure) FIG. 1 schematically shows the entire structure of a bellows pump as an embodiment. The bellows pump shown in the figure is of a horizontal double series, and includes left and right cylinder cases 1L and 1R, a pump head 2, bellows 4L and 4R disposed in a pair of cylinder chambers 3L and 3R, and bellows 4L and 4R. The connecting member 5 that connects the bellows in a state where the corresponding end portion is coupled to the free end surface side of the cylinder, and the corresponding bellows 4L and 4R provided in the cylinder cases 1L and 1R detect the contracted state or the extended state. A sensor G, F, a port-switching solenoid valve 6 that enables the compressed gas for driving to be alternately pumped to the cylinder chambers 3L, 3R, and a connecting member 11 as a passage communicating the cylinder chambers 3L, 3R. A normally closed electromagnetic valve 12 provided, a control unit 10A for receiving the detection signals of the sensors G and F and controlling the electromagnetic valve 6 and the electromagnetic valve 12 are provided.

  Here, the above-described constituent members are substantially the same as the conventional one except for the normally closed electromagnetic valve 12 and the configuration related to the electromagnetic valve 12. That is, the cylinder cases 1L and 1R have a substantially cylindrical shape that closes the rear end surface, have the supply and discharge ports D and C on the outer periphery, and the front opening is mounted on the corresponding end surface side of the pump head 2, respectively. Cylinder chambers 3L and 3R are defined between the pump head 2 and the cylinder. The pump head 2 has a substantially disc shape, a suction passage and a discharge passage communicating with the outer periphery, a pair of through holes communicating with one of these and the both end surfaces of the head, and a plurality of the plurality of disposed through the through holes. It has a check valve.

  The bellows 4L and 4R are made of plastic and have a cylindrical shape that can be expanded and contracted. One end of the opening is attached to the corresponding end surface of the pump head 2, and the other end is closed. A metal fitting, a connecting plate, and the like are attached to the other end side, and corresponding ends of the connecting member 5 are coupled using these. For this reason, the bellows 4L and the bellows 4R are configured such that when one bellows contracts, the other bellows extends in conjunction with the other via the connecting member 5. The cylinder chambers 3L and 3R are provided with a leak sensor (not shown) so that liquid leakage from the bellows 4L and 4R can be detected. The sensor F detects the stroke end when the bellows 4R is contracted to the design value. The sensor G detects the stroke end when the bellows 4L is contracted to the design value. Each detection signal is transmitted to the control unit 10A. For details of these members, see, for example, Japanese Patent Application Laid-Open No. 11-22646 and Japanese Patent Application Laid-Open No. 2001-140752 other than Patent Document 1.

The port-switching solenoid valve 6 is a type that switches the flow path when the spool moves in the axial direction, and has a 5-port, 3-position, double solenoid, closed center (when the ports A and B are closed when not energized). It is used. In this example,
A P port for introducing a compressed gas for driving, and an A port and a B port which are alternately communicated with the P port and allow the compressed gas to be supplied to the cylinder chambers 3R and 3L via the first pipe 7 and the second pipe 8. And at least an E1 port and an E2 port that are alternately communicated with the A port and the B port and allow the compressed gas to be discharged from the cylinder chambers 3R and 3L through the first pipe 7 and the second pipe 8. ing. The first pipe 7 connects the A port and the supply / discharge port C of the cylinder chamber 3R, and the second pipe 8 connects the B port and the supply / discharge port D of the cylinder chamber 3L.

  The connecting pipe 11 connects the first pipe 7 and the second pipe 8, and communicates the cylinder chamber 3 </ b> L and the cylinder chamber 3 </ b> R with the solenoid valve 6 closing both the A port and the B port. It becomes a dedicated passage. The normally closed solenoid valve 12 is a suitable example as a passage opening / closing valve, and is controlled by the control unit 10A. That is, 10 A of control parts receive the detection signal of the sensor G or the sensor F, control the solenoid valve 6 (corresponding solenoid), or control the solenoid valve 12. The solenoid valve 12 is preferably a 2-port valve or a 3-port valve. In the case of a 3-port valve, one of the ports is closed and used as a 2-port valve, or used in combination with an air operated valve. Since such a solenoid valve 12 is a normally closed solenoid valve, it is easy to handle, and the control can be simplified by using it as the control unit for the port switching solenoid valve 10A.

(First Modification) FIG. 2 schematically shows the overall structure of a bellows pump as a modification of FIG. The bellows pump in the figure is an example in which the configuration of the connecting pipe 11A is changed from the structure in FIG. 1, and the same members and parts as those in FIG.

  That is, each cylinder case 1L, 1R has supply / exhaust ports D1, C1 in another place together with the supply / discharge ports D, C. The connecting pipe 11A has one end connected to the supply / discharge port D1 of the cylinder case 1L and the other end connected to the supply / discharge port C1. In this modified example, the connecting pipe 11A is a dedicated passage that communicates the cylinder chamber 3L and the cylinder chamber 3R, and the solenoid valve 6 is closed from both the A port and the B port while the solenoid valve 12 is closed. When switched to the valve open state, the compressed gas in the high pressure side cylinder chamber is caused to flow into the low pressure side cylinder chamber.

  Further, the above modification is further developed, for example, a quick exhaust valve 9 as shown in FIG. 9 is added, or a dedicated passage for communicating the cylinder chamber 3L and the cylinder chamber 3R and an electromagnetic provided in the passage. You may comprise so that the valve 12 may be incorporated in a bellows pump.

(Pump drive method) In this structure, at the start of activation, it is determined which of the cylinder chambers 3R and 3L is supplied with compressed gas. Here, it shall supply from the cylinder chamber 3R. Further, when the pump is stopped, both solenoids of the solenoid valve 6 are demagnetized, and the compressed gas is not supplied to either the A port or the B port. In this structure, when the pump is started, the solenoid of the solenoid valve 6 (A port side solenoid) is excited, and the compressed gas passes through the A port and the pipe 7 from the P port through the supply / discharge port C of the cylinder case 1R. It is supplied to the chamber 3R. At this time, the compressed gas in the cylinder chamber 3L is exhausted from the supply port D of the cylinder case 1L through the pipe 8 and the B port of the solenoid valve 6 via the E2 port.

  Thus, when the compressed gas enters the cylinder chamber 3R and the compressed gas in the cylinder chamber 3L is discharged, a pressure difference is generated between the cylinder chamber 3R and the cylinder chamber 3L, the bellows 4R is contracted, and the bellows 4L is connected to the connecting member 5. It is extended with the reciprocating motion. When the bellows 4R is sufficiently contracted, the sensor F for detecting the stroke end is turned ON. The sensor F transmits the detection signal to the control unit 10A. Then, the control unit 10A sends a signal to the solenoid valve 6 so that both solenoids are demagnetized. With this signal, the compressed gas is not supplied to either the A port or the B port. In synchronization with this, the control unit 10A sends a signal to the solenoid valve 12 so that the solenoid is excited. With this signal, the solenoid valve 12 is switched from the closed state to the open state (in FIG. 3A, J-open indicates the open state). As a result, the compressed gas in the high pressure side cylinder chamber 3R in which the bellows 4R is contracted flows from the supply / discharge port C or C1 to the connection pipe 11 or 11A and the electromagnetic valve 12, and further through the supply / discharge port D or D1. It flows into the extending low pressure side cylinder chamber 3L.

  The controller 10A controls the solenoid valve 12 so that the solenoid of the solenoid valve 12 is demagnetized from the open state to the closed state after time T from the time when the sensor F is turned on, and the solenoid valve 6 has a solenoid (on the B port side). Send a signal to energize the solenoid. When the solenoid of the solenoid valve 6 (the solenoid on the B port side) is excited, the compressed gas is supplied from the P port of the solenoid valve 6 to the cylinder chamber 3L through the B port and the pipe 8 from the supply / discharge port D. At this time, the compressed gas remaining in the cylinder chamber 3R is exhausted from the supply / exhaust port C through the pipe 7 and the A port of the electromagnetic valve 6 via the E1 port.

  Thus, when compressed gas enters the cylinder chamber 3L and the compressed gas in the cylinder chamber 3R is discharged, a pressure difference is generated between the cylinder chamber 3R and the cylinder chamber 3L, and the bellows 4L contracts (that is, discharges liquid). Mode), and the bellows 4R is expanded (that is, a mode for sucking liquid) with the reciprocating motion of the connecting member 5. When the bellows 4L is sufficiently contracted, the sensor G for detecting the stroke end is turned ON. The sensor G transmits the detection signal to the control unit 10A. Then, the control unit 10A sends a signal to the solenoid valve 6 so that both solenoids are demagnetized. With this signal, the compressed gas is not supplied to either the A port or the B port. In synchronization with this, the control unit 10A sends a signal to the solenoid valve 12 so that the solenoid is excited. With this signal, the solenoid valve 12 is switched from the closed state to the open state (in FIG. 3A, J-open indicates the open state). As a result, the compressed gas in the high-pressure side cylinder chamber 3L, in which the bellows 4L is contracted this time, passes through the connection pipe 11 or 11A and the electromagnetic valve 12 from the supply / discharge port D or D1, and further through the supply / discharge port C or C1. 4R flows into the extending low pressure side cylinder chamber 3R.

  The controller 10A controls the solenoid valve 12 so that the solenoid of the solenoid valve 12 is demagnetized from the open state to the closed state after time T after the sensor G is turned ON, and the solenoid valve 6 is controlled by a solenoid (on the A port side). Send a signal to energize the solenoid. When the solenoid of the solenoid valve 6 (the solenoid on the A port side) is excited, the compressed gas is supplied from the P port of the solenoid valve 6 to the cylinder chamber 3R from the supply / discharge port C via the A port and the pipe 7. At this time, the compressed gas remaining in the cylinder chamber 3L is exhausted from the supply / exhaust port D through the pipe 8 and the B port of the electromagnetic valve 6 via the E2 port.

  In the bellows pumps shown in FIGS. 1 and 2, the above operation is repeated. FIG. 3A is a time chart showing the above operation timing, and FIG. 3B is a time chart of FIGS.

  In the conventional driving method, as shown in FIG. 3B, the supply time for supplying the compressed gas for driving from the electromagnetic valve 6 (A port or B port) to one or the other cylinder chamber, and the compressed gas in the other or one cylinder chamber are supplied. The exhaust time for exhausting from the solenoid valve 6 (E1 port or E2 port) or the quick exhaust valve 9 (H1 port or H2 port) is alternately performed continuously.

  On the other hand, in the driving method of the present invention, as shown in FIG. 3A, the supply time for supplying the driving compressed gas from the electromagnetic valve 6 (A port or B port) to one or the other cylinder chamber, and the other or one cylinder The exhaust time for exhausting the compressed gas in the chamber from the electromagnetic valve 6 (E1 port or E2 port) is alternately performed in a manner shifted by T time. In the present invention, the T time is used to flow the compressed gas in the high pressure side cylinder chamber into the low pressure side cylinder chamber among the cylinder chambers.

(Second Modification) FIG. 4 schematically shows the entire structure of the bellows pump as a modification. The bellows pump shown in the figure is a horizontal double series, and includes left and right cylinder cases 21L and 21R and pump heads 22L and 22R, bellows 24L and 24R arranged in a pair of cylinder chambers 23L and 23R, and each bellows 24L, The connecting member 25 that connects the bellows with the corresponding end portion coupled to the free end face side of the 24R, the sensors G1 and F1 corresponding to the sensors G and F, and the cylinder chambers 23L and 23R are used for driving. A port-switching solenoid valve 6 that allows compressed gas to be alternately pumped, a normally-closed solenoid valve 12 provided in a connecting member 11 as a passage communicating each cylinder chamber 23L, 23R, and sensors G1, F1 A control unit 10A that receives the detection signal and controls the solenoid valve 6 and the solenoid valve 12 is provided.

  In FIG. 4, the same members and parts as those in FIG. Specifically, among the constituent members, the port switching type electromagnetic valve 6, the connection officer 11, the normally closed type electromagnetic valve 12, the electromagnetic valve 6 and the control unit 10A for controlling the electromagnetic valve 12 are the same as those in FIG. On the other hand, the cylinder cases 21L and 21R are assembled to the apparatus main body 20 in a state of being connected to the corresponding pump heads 22L and 22R. The fixed-side opening ends of the bellows 24L and 24R communicate with the inlet / outlet ports 24a and 24a of the corresponding pump heads 22L and 22R, and communicate with a liquid feed pipe 27 with two check valves 26. The sensors G1 and F1 are proximity sensors, for example, and are provided on the rear end face side of the cylinder cases 21L and 21R to detect the contracted state or the extended state of the corresponding bellows 24L and 24R.

(Pump drive method) In this structure, the above-described pump drive method applies almost as it is. That is, in this structure, when the pump is started, the solenoid of the solenoid valve 6 (A port side solenoid) is excited, and the compressed gas passes through the A port and the pipe 7 from the P port to the cylinder through the inlet / outlet C of the cylinder case 21R. It is supplied to the chamber 23R. At this time, the compressed gas in the cylinder chamber 23L is exhausted from the supply port D of the cylinder case 21L through the pipe 8 and the B port of the electromagnetic valve 6 via the E2 port.

  In this way, when the compressed gas enters the cylinder chamber 23R and the compressed gas in the cylinder chamber 23L is discharged, a pressure difference is generated between the cylinder chamber 23R and the cylinder chamber 23L, the bellows 24R is contracted, and the bellows 24L is connected to the connecting member 25. It is extended with the reciprocating motion. When the bellows 24L is sufficiently extended, the sensor G1 is turned on. The sensor G1 transmits the detection signal to the control unit 10A. Then, the control unit 10A sends a signal to the solenoid valve 6 so that both solenoids are demagnetized. With this signal, the compressed gas is not supplied to either the A port or the B port. In synchronization with this, the control unit 10A sends a signal to the solenoid valve 12 so that the solenoid is excited. With this signal, the solenoid valve 12 is switched from the closed state to the open state. As a result, the compressed gas in the high-pressure side cylinder chamber 23R in which the bellows 24R is contracted flows from the supply / discharge port C through the connection pipe 11, the electromagnetic valve 12, and the supply / discharge port D, and the low-pressure side where the bellows 24L extends. It flows into the cylinder chamber 23L.

  10 hours after the sensor G1 is turned ON, the control unit 10A controls the solenoid of the solenoid valve 12 so that the solenoid is demagnetized so that the solenoid valve 6 is opened to the closed state. Send a signal to energize the solenoid. When the solenoid of the solenoid valve 6 (B port side solenoid) is excited, the compressed gas is supplied from the P port of the solenoid valve 6 to the cylinder chamber 23L from the supply / discharge port D via the B port and the pipe 8. At this time, the compressed gas remaining in the cylinder chamber 23R is exhausted from the supply / exhaust port C through the pipe 7 and the A port of the electromagnetic valve 6 via the E1 port.

  Thus, when the compressed gas enters the cylinder chamber 23L and the compressed gas in the cylinder chamber 23R is discharged, a pressure difference is generated between the cylinder chamber 23R and the cylinder chamber 23L, and the bellows 24L contracts (that is, discharges liquid). Mode), and the bellows 24R is extended (that is, a mode of sucking liquid) with the reciprocating movement of the connecting member 5. When the bellows 24R is sufficiently extended, the sensor F1 is turned on. The sensor F1 transmits the detection signal to the control unit 10A. Then, the control unit 10A sends a signal to the solenoid valve 6 so that both solenoids are demagnetized. With this signal, the compressed gas is not supplied to either the A port or the B port. In synchronization with this, the control unit 10A sends a signal to the solenoid valve 12 so that the solenoid is excited. With this signal, the solenoid valve 12 is switched from the closed state to the open state. As a result, the compressed gas in the high-pressure side cylinder chamber 3L, in which the bellows 4L is contracted this time, extends from the supply / discharge port D through the connection pipe 11, the electromagnetic valve 12, and the supply / discharge port C, and the bellows 24R extends. It flows into the low pressure side cylinder chamber 23R.

  The control unit 10A controls the solenoid of the solenoid valve 12 so that the solenoid of the solenoid valve 12 is demagnetized from the open state to the closed state after T time from the time when the sensor F1 is turned on. Send a signal to energize the solenoid. When the solenoid of the solenoid valve 6 (A port side solenoid) is excited, the compressed gas is supplied from the P port of the solenoid valve 6 to the cylinder chamber 23R from the supply / discharge port C via the A port and the pipe 7. At this time, the compressed gas remaining in the cylinder chamber 23L is exhausted from the supply / exhaust port D through the pipe 8 and the B port of the electromagnetic valve 6 via the E2 port. In this structure, the above operation is repeated.

(Embodiment) Next, the present inventors use a commercially available bellows pump (type of FIG. 1) which is a semiconductor specification, and a connecting pipe 11 and a normally closed solenoid valve (two-port valve) as shown in FIG. An example when the effectiveness of the present invention is examined will be described. In addition, the pump body of the bellows pump (the body constituted by reference numerals 1 to 5 in FIG. 1) has a wetted part material (a bellows, a valve case of a pump head and a check valve, etc.) PTFT, PFA, cylinder case and pump The frame is cast aluminum.

  In the test, room temperature fresh water was used as the transfer liquid, compressed air was used as the driving compressed gas, and data was collected by changing the pump driving pressure, pump discharge load, and the like. In that case, in the test, the port-switching solenoid valve 6 uses a 5-port, 3-position, double solenoid, closed-center structure, the normally-closed solenoid valve 12 uses a 2-port structure, Any one of the solenoid of the A port side solenoid, the B port side solenoid, and the solenoid of the solenoid valve 12 is excited. This is to simplify the control of the solenoid valve 6 and the solenoid valve 12. However, in actual operation, the same effect can be obtained even if the excitation states of the solenoids overlap each other for a short time or are separated for a short time.

  5 to 7 show representative examples of test results. Each graph in FIG. 5 and FIG. 6 is data when the T time in FIG. 3A is changed under the same conditions. The time T indicates the time (1/1000 second) in which the compressed gas in the high-pressure side cylinder chamber flows into the low-pressure side cylinder chamber in the open state of each cylinder chamber.

  The graph in Fig. 5 shows the flow rate of compressed air when the time T is set to 0 seconds, 30/1000 seconds, 45/1000 seconds, 60/1000 seconds, 75/1000 seconds, and 90/1000 seconds, that is, port switching type. This is Test Example 1 when a change in the flow rate (N liter / min) of compressed air supplied from the solenoid valve 6 side to each cylinder chamber is examined. In this test result, if the time T = 0 seconds, that is, the conventional pump structure, the flow rate of compressed air is 215 liters / minute. On the other hand, in the pump structure of the present invention (structure in which the compressed gas in the high pressure side cylinder chamber flows into the low pressure side cylinder chamber), the flow rate of the compressed air is 185 liters / minute when T = 30/1000 seconds, It was 181 liters / minute at 45/1000 seconds, 178 liters / minute at 60/1000 seconds, 174 liters / minute at 75/1000 seconds, and 170 liters / minute at 90/1000 seconds. . That is, it can be seen that the pump structure of the present invention has a flow rate of compressed air that is at least 10% lower than that of the conventional pump structure in which the compressed air in the high pressure side cylinder chamber does not flow into the low pressure side cylinder chamber.

  The graph in Figure 6 shows the pump speed (stroke / min) when the time T is set to 0 seconds, 30/1000 seconds, 45/1000 seconds, 60/1000 seconds, 75/1000 seconds, and 90/1000 seconds. Test example 2 In this test result, when the time T is 0 second, that is, the conventional pump structure, the pump speed is 51.6 stroke / min. On the other hand, with the pump structure of the present invention, the pump speed is 54.0 strokes / minute when T = 30/1000 seconds, 50.8 strokes / minute when 45/1000 seconds, and 51.0 when 60/1000 seconds. It was 49.6 strokes / minute at 75/1000 seconds, and 48.6 strokes / minute at 90/1000 seconds.

  The graph of FIG. 7 shows the compressed air consumption (N liter / stroke) calculated from the test results of FIGS. 5 and 6, that is, (compressed air flow rate / pump speed). In (), the compressed air consumption rate at each time when time T = 0 is set to 100% is shown. From FIG. 7, for example, when the time T = 30/1000 seconds, the compressed air consumption rate shows a peak at 82.3%. This is because the time T = 0 corresponds to the conventional pump structure. For example, in the pump structure of the present invention, by setting the time T = 30/1000 seconds, the compressed air consumption rate is (100-82.3 =) 17.7% The usefulness of the present invention was confirmed.

  It should be noted that the present invention is not limited to the above forms and modifications, and only needs to satisfy the requirements specified in the claims, and the details can be variously modified and expanded with reference to the above specific examples. It is.

It is a lineblock diagram showing the whole bellows pump concerning the form of the present invention. It is a block diagram which shows the 1st modification of the said form. (A) is a figure which shows the time chart of invention bellows pump, (b) is a figure which shows the time chart of a conventional bellows pump. It is a block diagram which shows the 2nd modification of the said form. It is a graph which shows the relationship between the time T in the valve opening state of a valve (normally closed electromagnetic valve), and the flow volume of the compressed air to a cylinder chamber as a test result of an Example. It is a graph which shows the relationship between the time T in the valve opening state of a valve (normally closed solenoid valve), and pump speed as a test result of an Example. It is a graph which shows the relationship between the time T in the valve opening state of the valve (normally closed solenoid valve), the compressed air consumption, and the compressed air consumption rate calculated from each test result. It is explanatory drawing which shows the whole conventional bellows pump. It is explanatory drawing which shows the whole other conventional bellows pump.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1L, 1R ... Cylinder case 2 ... Pump head 3L, 3R ... Cylinder chamber 4L, 4R ... Bellows C, D ... Supply / exhaust port F, G ... Sensor 5 ... Connection member 6 ... Port switching type solenoid valve 7 ... First piping 8 ... 2nd piping 10 ... Control part 11, 11A ... Connection pipe (passage)
21L, 21R ... Cylinder case 22L, 22R ... Pump head 23L, 23R ... Cylinder chamber 24L, 24R ... Bellows 25 ... Connecting member F1, G1 ... Sensor

Claims (4)

A pair of cylinder chambers, a pair of bellows disposed in each of the cylinder chambers, a connecting member that connects the bellows, and a port switching type capable of alternately pumping driving compressed gas to the cylinder chambers An electromagnetic valve; and a control unit that controls the electromagnetic valve, wherein the bellows are alternately expanded and contracted with the reciprocating motion of the compressed gas and the connecting member, so that liquid is sucked into one side and discharged from the other. In bellows pump,
It has a passage connecting each cylinder chamber and a valve for opening and closing the passage, and among the cylinder chambers, the compressed gas of the high pressure side cylinder chamber can flow into the low pressure side cylinder chamber. Bellows pump to do.   The passage includes a first pipe connecting one of the cylinder chambers and a corresponding port of the solenoid valve, and a second pipe connecting the other of the cylinder chambers and a corresponding port of the solenoid valve. The bellows pump according to claim 1, wherein the bellows pump is a connected connecting pipe.   The passage includes a first pipe connecting one of the cylinder chambers and a corresponding port of the solenoid valve, and a second pipe connecting the other of the cylinder chambers and a corresponding port of the solenoid valve. The bellows pump according to claim 1, wherein the bellows pump is a connection pipe that is provided separately and connects between one and the other of the cylinder chambers. A pair of cylinder chambers, a pair of bellows disposed in each cylinder chamber, a connecting member that connects the bellows, and a port-switching electromagnetic that alternately supplies compressed gas for driving to each cylinder chamber In a driving method of a bellows pump comprising a valve, wherein the bellows are alternately expanded and contracted with the reciprocating motion of the compressed gas and the connecting member to suck liquid into one side and discharge from the other.
In a state where the supply of the compressed gas to each cylinder chamber is stopped, a valve provided in a passage connecting the cylinder chambers is switched from a closed state to an open state, and the bellows among the cylinder chambers A method for driving a bellows pump, wherein the compressed gas in the high pressure side cylinder chamber in which the bellows is contracted passes through the process of flowing into the low pressure side cylinder chamber in which the bellows is extended.

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