JP2008163853A - Electromagnetically driven pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetically driven pump for enhancing an operational continuity, by realizing high pressure of fluid pressure, without reducing the cross-sectional area of a thrust generating part in a cylinder body. <P>SOLUTION: Fluid filled in a first cylinder chamber 4b smaller in the cross-sectional area than a second cylinder chamber 5, is sent out by being put under a high pressure by pressing by a moving piece 8 by using thrust generated in the trust generating part 10 of the second cylinder chamber 5 by carrying an electric current to an electromagnetic coil 15. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetically driven pump suitable for an application requiring high pressure such as a dispenser, an analyzer, a fuel cell, and an ink jet printer.

For example, an electromagnetically driven pump is used as the direct acting pump for fluid conveyance. The electromagnetically driven pump is provided with a mover (piston or plunger) having a magnet that generates thrust in a cylinder body so as to be slidable. In addition, a coil is provided on the outer periphery of the cylinder body, and the movable element is reciprocated by the reaction force of the electromagnetic force generated by energizing the coil to open and close the valves (valves) provided on both sides of the movable element. The fluid is sucked into one cylinder chamber and the fluid in the other cylinder chamber is sent out. The electromagnetically driven pump has an advantage that the pump size can be reduced and the configuration can be made relatively simple (Patent Document 1).
JP 2004-124724 A

In order to further increase the fluid pressure of the electromagnetically driven pump, it is conceivable to reduce the pipe cross-sectional area of the cylinder body and increase the input to generate a high thrust in the mover. However, since the mover is provided with a magnet which is a thrust generating portion, when the pipe cross-sectional area of the cylinder chamber is reduced, the magnet diameter is reduced and high thrust cannot be obtained. Further, increasing the input to the coil is not preferable for energy saving.
In addition, if the fluid push-out portion and the thrust generating portion are formed to have different cross-sectional areas in the cylinder body, the outer peripheral surface of the mover and the inner wall surface of the cylinder body are moved in the moving space of the thrust generating portion as the mover reciprocates. Since the fluid leaks from the gap, the mover may not be able to move when the fluid is an incompressible liquid.

  The present invention has been made to solve these problems, and the purpose of the present invention is to increase the fluid pressure without reducing the cross-sectional area of the thrust generating portion in the cylinder body and to improve the operation continuity. It is to provide an electromagnetically driven pump.

In order to achieve the above object, the present invention comprises the following arrangement.
A cylinder body provided with a cylinder chamber having a multi-stage diameter with openings formed at both ends and the inner side being expanded, and a first cylinder chamber communicating with each of the openings and the both ends of the hollow mover shaft are slid A thrust generating portion inserted in a movable manner and having a magnet on the outer peripheral side of the middle portion of the mover shaft is provided in the second cylinder chamber so as to be openable and closable in the first cylinder chamber. The first and second valves that draw fluid from the external flow path into the first cylinder chamber and send the fluid from the first cylinder chamber to the external flow path, and an air-core electromagnetic coil on the outer periphery of the cylinder body An electromagnetically driven pump that opens and closes the first and second valves to transport fluid by energizing the electromagnetic coil and reciprocatingly driving the mover in the axial direction of the cylinder body. The second cylinder chamber Wherein the sending the filled utilizing the thrust generated by the force generating unit in a small first cylinder chamber cross-sectional area than that of the second cylinder chamber fluid and high pressure by being pressed by the movable element.

Further, when the mover reciprocates, the fluid that leaks from the first cylinder chamber to the second cylinder chamber passes through a gap formed between the thrust generator and the inner wall surface of the second cylinder chamber. The second cylinder chamber is on the opposite side to the moving direction of the cylinder.
Also, a through hole is formed in the thrust generating portion along the axial direction, and the fluid leaked from the first cylinder chamber to the second cylinder chamber when the mover reciprocates is moved in the moving direction of the thrust generating portion. The second cylinder chamber on the opposite side escapes through the through hole.
In addition, the mover shaft is formed with communication holes perpendicular to the axial direction on both sides of the thrust generating portion, and the fluid leaked from the first cylinder chamber to the second cylinder chamber when the mover reciprocates. From the other communication hole through the hollow shaft hole to the second cylinder chamber on the opposite side.
In this case, when the mover shaft moves toward the discharge side, the fluid filled in the shaft hole moves to the suction side opening of the mover shaft to prevent the suction valve from closing. A valve is provided.

  Further, when the mover reciprocates, the fluid leaked from the first cylinder chamber to the second cylinder chamber is caused by a gap formed between the thrust generating portion and the inner wall surface of the second cylinder chamber, and thrust generation At least two of the through-holes along the axial direction in the part and the communication holes perpendicular to the axial direction formed on both sides of the thrust generating part on the mover shaft into the opposite second cylinder chamber Characterized by escape.

  If the above-described electromagnetically driven pump is used, the cylinder body provided with a cylinder chamber having a multi-stage diameter in which openings are formed at both ends and the inner side is expanded is communicated with the first cylinder chamber that communicates with each of the openings. Both ends of the hollow mover shaft are slidably inserted, and a thrust generating portion having a magnet provided on the outer peripheral side of the middle portion of the hollow mover shaft is housed in the second cylinder chamber and the mover is assembled. Energizing the coil and pressing the fluid filled in the first cylinder chamber having a smaller cross-sectional area than the second cylinder chamber with the mover using the thrust generated in the thrust generating portion of the second cylinder chamber At high pressure. As a result, the fluid pressure can be increased by the mover without reducing the flow path cross-sectional area in the cylinder body.

  Further, when the mover reciprocates, the fluid that leaks from the first cylinder chamber to the second cylinder chamber passes through a gap formed between the thrust generator and the inner wall surface of the second cylinder chamber. Through the second cylinder chamber on the opposite side of the moving direction, or a through-hole is formed in the thrust generating portion along the axial direction, so that the first move from the first cylinder chamber when the mover reciprocates. The fluid leaking into the second cylinder chamber escapes from the first cylinder chamber to the second cylinder chamber opposite to the moving direction of the thrust generating section through the through hole, or when the mover reciprocates. The fluid that has entered the second cylinder chamber by letting the fluid leaking into the cylinder chamber escape from the one communication hole through which the thrust generating unit moves through the hollow shaft hole to the second cylinder chamber on the opposite side, Especially incompressible liquid There can be maintained operational continuity without interfering with reciprocation of the thrust generating unit.

  Further, when the mover reciprocates, the fluid leaked from the first cylinder chamber to the second cylinder chamber is caused by a gap formed between the thrust generating portion and the inner wall surface of the second cylinder chamber, and thrust generation At least two of the through-holes along the axial direction in the part and the communication holes perpendicular to the axial direction formed on both sides of the thrust generating part on the mover shaft into the opposite second cylinder chamber When escaped, the outer diameter of the thrust generating portion is not reduced more than necessary, and therefore the continuity of operation can be improved without reducing the thrust of the mover.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best embodiment of an electromagnetically driven pump according to the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, an electromagnetically driven pump that delivers an incompressible fluid (particularly liquid such as water or refrigerant) will be described as an example of the electromagnetically driven pump.

First, a schematic configuration of the electromagnetically driven pump will be described with reference to FIG.
The cylinder body 1 is assembled by stacking the first block body E and the second block body G with the ring material F interposed therebetween. An opening (suction port) 2 and an opening (sending port) 3 are formed at both ends of the cylinder. Further, the cylinder body 1 is provided with a plurality of cylinder chambers having a multi-stage diameter whose inner side is enlarged in diameter (having a large sectional area).

  That is, a first cylinder chamber 4a (suction side) having a diameter larger than that adjacent to the suction port 2 and a first cylinder chamber 4b (sending side) having a diameter larger than that are provided adjacent to the delivery port 3. ing. A second cylinder chamber 5 having a larger diameter (large cross-sectional area) is provided between the first cylinder chamber 4a and the first cylinder chamber 4b. For example, a metal material made of a non-magnetic material is used for the cylinder body 1. A cylindrical valve seat member 6 is fitted into the first cylinder chamber 4a, and a first valve 7 is provided in the valve hole 6a of the valve seat member 6 so as to be opened and closed. For the first valve 7, for example, a resin material such as rubber is preferably used.

A movable element 8 is assembled to the cylinder body 1 so as to be able to reciprocate. The mover 8 is provided with a hollow mover shaft 9 and a thrust generator 10 on the outer peripheral side thereof. The mover shaft 9 has a suction opening 9a and a delivery opening 9b on both ends. Both end sides of the mover shaft 9 are slidably inserted into the first cylinder chambers 4a and 4b. The shaft hole 9c of the mover shaft 9 communicates with each of the first cylinder chambers 4a and 4b, and forms a fluid flow path in the cylinder body 1. A second valve 11 is provided in the delivery side opening 9b so as to be openable and closable. For the second valve 11, for example, a resin material such as rubber is preferably used.
It is also conceivable to provide a sealing material such as an O-ring between the mover shaft 9 and the cylinder body 1 to prevent fluid leakage from the first cylinder chambers 4a and 4b to the second cylinder chamber 5. However, since the life due to wear of the sealing material is short and part processing is required, the structure is such that fluid leakage from the first cylinder chambers 4a and 4b to the second cylinder chamber 5 is allowed.

  The thrust generating unit 10 provided on the outer peripheral side of the middle part of the mover shaft 9 is provided with a magnet 12. The magnet 12 has an annular shape and is magnetized in the axial direction. On both sides of the magnet 12, yoke parts 13 using a magnetic material are provided. The outer peripheral surface portion 13a of each yoke portion 13 extends in the axial direction. That is, the magnetic flux acting surface of the yoke portion 13 is formed on the outer peripheral surface portion 13a in the radial direction. The thrust generating unit 10 is accommodated in the second cylinder chamber 5, and a gap 14 is formed between the outer peripheral surface portion 13 a of the thrust generating unit 10 and the inner wall surface 5 a of the second cylinder chamber 5.

  An air core electromagnetic coil 15 is provided concentrically with the mover 8 on the outer periphery of the cylinder body 1. The electromagnetic coil 15 is pressed and fixed to the cylinder body 1 (first block pair E) in the axial direction by the outer case 16. The exterior body 16 is made of an insulating member such as a resin material. An O-ring 17 for sealing is fitted into the ring material F sandwiched between the first block pair E and the second block body G.

By switching the direction in which the electromagnetic coil 15 is energized, the mover 8 is reciprocated in the axial direction of the cylinder body 1 by the reaction force of the electromagnetic force acting on the electromagnetic coil 15. For example, when the mover 8 moves upward, the second valve 11 is closed, the fluid is sent from the first cylinder chamber 4b to the external flow path through the delivery port 3, and only while the first valve 7 is open. Fluid is sucked from the suction port 2 into the first cylinder chamber 4a. When the mover 8 moves downward, the fluid moves from the shaft hole 9c of the mover shaft 9 to the first cylinder chamber 4b only while the second valve 11 is open, and the first valve 7 The fluid moves from the first cylinder chamber 4a into the shaft hole 9c while being closed. Such an operation is repeated to send the fluid from the cylinder body 1.
As described above, the electromagnetic coil 15 is energized and the thrust generated in the thrust generating portion 10 of the second cylinder chamber 5 is used to enter the first cylinder chamber 4 b having a smaller cross-sectional area than the second cylinder chamber 5. The fluid filled with the second valve 11 closed is pressed by the mover 8 to be sent out at a high pressure. Therefore, the fluid pressure can be increased by the mover 8 without reducing the cross-sectional area of the flow path in the cylinder body 1.

  Further, when the fluid leaking from the first cylinder chambers 4a and 4b to the second cylinder chamber 5 is filled when the mover 8 reciprocates, the thrust of the mover 8 decreases and the movement becomes worse. It is assumed that For this reason, the fluid accumulated in the second cylinder chamber 5 is moved through the gap 14 formed between the outer peripheral surface portion 13 a of the thrust generating portion 10 and the inner wall surface 5 a of the second cylinder chamber 5. It escapes in the 2nd cylinder chamber 5 on the opposite side to a direction (refer arrow P).

  Further, in the left half view of FIG. 1, a through hole 18 may be formed in the thrust generation unit 10 along the axial direction. That is, the through hole 18 is formed in the magnet 12 and the yoke portion 13 that sandwiches the magnet 12. When the mover 8 reciprocates, the fluid leaked from the first cylinder chambers 4a and 4b to the second cylinder chamber 5 enters the second cylinder chamber 5 on the side opposite to the moving direction of the thrust generator 10 into the through-hole. Escape through 18 (see arrow Q). In this case, the gap 14 formed between the outer peripheral surface portion 13a of the thrust generating portion 10 and the inner wall surface 5a of the second cylinder chamber 5 may not be provided more than necessary. Alternatively, it is also possible to maintain the continuity of operation of the mover 8 by providing a clearance 14 for allowing the fluid to escape and providing a through hole 18 of the thrust generating unit 10 and securing a predetermined amount of fluid passing through these holes. is there.

  Further, in the left half view of FIG. 1, communication holes 19 that connect the shaft hole 9 c and the second cylinder chamber 5 on both sides of the thrust generating portion 10 to the hollow mover shaft 9 are arranged in directions orthogonal to the axial direction. Is formed. When the mover 8 reciprocates, the fluid leaked from the first cylinder chambers 4a and 4b to the second cylinder chamber 5 moves from one communication hole 19 through which the thrust generating unit 10 moves to the other communication hole through the shaft hole 9c. 19 to escape into the second cylinder chamber 5 on the opposite side (see arrow R). In this case, the gap 14 formed between the outer peripheral surface portion 13a of the thrust generating portion 10 and the inner wall surface 5a of the second cylinder chamber 5 may not be provided more than necessary, and the thrust generating portion 10 has a through hole. 18 is not necessarily provided.

Alternatively, a gap 14 formed between the thrust generating unit 10 and the second cylinder chamber 5, a through hole 18 in the axial direction in the thrust generating unit 10, and a mover shaft 9 formed on both sides of the thrust generating unit 10, respectively. It is also possible to maintain the continuity of operation of the mover 8 by combining any two or more of the communicating holes 19 and securing a predetermined amount of fluid passing through them.
As described above, the fluid that has entered the second cylinder chamber 5, particularly the incompressible liquid, can maintain the continuity of operation without hindering the reciprocating motion of the thrust generating unit 10.

  FIG. 2 shows a pump structure in which a gap 14 formed between the thrust generating unit 10 and the second cylinder chamber 5 and a through hole 18 along the axial direction are provided in the thrust generating unit 10. Since the gap 14 and the through hole 18 are factors that reduce the thrust of the thrust generating unit 10, it is desirable that the gap 14 and the through hole 18 be the minimum necessary for the cross-sectional area of the second cylinder chamber 5.

3A and 3B show the operation of the mover 8 and the flow of fluid in the second cylinder chamber 5 when the through-hole 18 is formed in the thrust generating unit 10. FIG. 3A shows a case where the mover 8 moves upward.
When the mover 8 moves upward, the closed first valve 7 is opened, and a predetermined amount of fluid is sucked from the suction port 2 into the first cylinder chamber 4a and the shaft hole 9c. Further, the second valve 11 that has been opened is closed, and a predetermined amount of fluid is sent from the first cylinder chamber 4 b to the delivery port 3 as the mover 8 moves. At this time, the fluid filled above the thrust generating portion 10 of the second cylinder chamber 5 passes through the gap 14 and the through hole 18 and is opposite to the moving direction of the thrust generating portion 10 (downward). Move in (see arrows P1, Q1).

  FIG. 3B shows a case where the mover 8 moves downward. When the mover 8 moves downward, the second valve 11 that has been closed opens, and the fluid in the shaft hole 9c moves to the first cylinder chamber 4b by a predetermined amount. Further, the first valve 11 that has been opened is closed, and the suction of fluid from the suction port 2 to the first cylinder chamber 4a is blocked. At this time, the fluid filled below the thrust generating portion 10 of the second cylinder chamber 5 passes through the gap 14 and the through hole 18 and the second cylinder chamber 5 on the opposite side (upward) of the moving direction of the thrust generating portion 10. Move inward (see arrows P2, Q2).

  FIG. 4 shows a pump structure in which communicating holes 19 are formed in the mover shaft 9 on both axial sides of the thrust generator 10. A third valve 20 is provided in the suction side opening 9 a of the mover shaft 9. The third valve 20 prevents the suction valve (first valve 7) from being closed by the movement of the fluid filled in the shaft hole 9c when the mover shaft 9 moves toward the discharge side. It is provided for the purpose. For the third valve 20, for example, a resin material such as rubber is preferably used as in the first and second valves.

5A and 5B show the operation of the mover 8 and the flow of fluid in the second cylinder chamber 5 when the communication hole 19 is formed in the mover shaft 9. FIG. 5A shows a case where the mover 8 moves upward.
When the mover 8 moves upward, the closed first valve 7 is opened, and a predetermined amount of fluid is sucked into the first cylinder chamber 4a from the opening 2. Further, the second valve 11 and the third valve 20 that have been opened are closed, and a predetermined amount of fluid is sent from the first cylinder chamber 4 b to the delivery port 3 as the mover 8 moves. At this time, the fluid filled above the thrust generating portion 10 of the second cylinder chamber 5 passes through the communication hole 19, the shaft hole 9 c, and the communication hole 19, and is the second (downward) side opposite to the moving direction of the thrust generating portion 10. 2 moves in the direction of the arrow into the cylinder chamber 5 (see arrow R1). Further, the third valve 20 is closed and the fluid filled in the shaft hole 9c is prevented from moving to the first cylinder chamber 4a, and the first valve 7 is not prevented from opening. Accordingly, a predetermined amount of fluid is sucked into the first cylinder chamber 4a from the suction port 2 only while the first valve 7 is open.

  FIG. 5B shows a case where the mover 8 moves downward. When the mover 8 moves downward, the fluid moves from the inside of the shaft hole 9c to the first cylinder chamber 4b, and the fluid moves from the first cylinder chamber 4a to the shaft hole 9c. The valve 11 and the third valve 20 are opened. Further, the first valve 7 that has been opened is closed, and the suction of fluid from the suction port 2 to the first cylinder chamber 4a is blocked. At this time, the fluid filled below the thrust generating portion 10 of the second cylinder chamber 5 passes through the communication hole 19, the shaft hole 9 c, and the communication hole 19, on the opposite side (upward) of the moving direction of the thrust generating portion 10. 2 moves in the direction of the arrow into the cylinder chamber 5 (see arrow R2).

The fluid is allowed to escape by combining with the communication hole 19 formed in the mover shaft 9 and any one of the gap 14 between the thrust generating portion 10 and the second cylinder chamber 5 or the through hole 18 provided in the thrust generating portion 10. These may be used in combination.
Moreover, although the sintered metal material is used for the magnet 12, the optimal thing is selected according to the kind of fluid. For example, ferritic magnets and samarium cobalt based magnets are used in consideration of rust prevention for water and the like, and neodymium / iron / boron based magnets are used for oil and the like.

It is sectional drawing of an electromagnetic drive pump, and explanatory drawing which shows the flow of the fluid in a 2nd cylinder chamber. It is sectional drawing which shows an example of an electromagnetic drive pump. It is explanatory drawing which shows the operation state of the pump of FIG. It is sectional drawing which shows an example of an electromagnetic drive pump. It is explanatory drawing which shows the operation state of the pump of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder main body 2 Suction port 3 Outlet 4a, 4b 1st cylinder chamber 5 2nd cylinder chamber 5a Inner wall surface 6 Valve seat member 6a Valve hole 7 1st valve 8 Movable element 9a Inlet side opening 9b Outlet side opening Part 9c Shaft hole 10 Thrust generating part 11 Second valve 12 Magnet 13 Yoke part 13a Outer peripheral surface part 14 Clearance 15 Electromagnetic coil 16 Exterior case 17 O-ring 18 Through hole 19 Communication hole 20 Third valve

Claims (6)

A cylinder body provided with a cylinder chamber having a multistage diameter in which openings are formed at both ends and the inner side is enlarged;
Both ends of the hollow mover shaft are slidably inserted in communication with the first cylinder chambers respectively communicating with the openings, and a thrust generating portion having a magnet on the outer peripheral side of the middle portion of the mover shaft is the second cylinder. A mover housed in the room;
The first cylinder chamber is provided so as to be openable and closable. One side sucks fluid from the external flow path into the first cylinder chamber, and the other side feeds fluid from the first cylinder chamber to the external flow path. A valve,
An air-core electromagnetic coil is disposed on the outer periphery of the cylinder body, and the electromagnetic coil is energized to reciprocate the mover in the axial direction of the cylinder body, thereby opening and closing the first and second valves to transport the fluid. An electromagnetically driven pump,
By energizing the electromagnetic coil and using the thrust generated in the thrust generating portion of the second cylinder chamber, the fluid filled in the first cylinder chamber having a smaller cross-sectional area than that of the second cylinder chamber is pressed by the mover. This is an electromagnetically driven pump that delivers high pressure.   Movement of the thrust generating portion through a gap formed between the thrust generating portion and the inner wall surface of the second cylinder chamber for the fluid leaked from the first cylinder chamber to the second cylinder chamber when the mover reciprocates. The electromagnetically driven pump according to claim 1, wherein the second cylinder chamber escapes in a direction opposite to the direction.   A through hole along the axial direction is formed in the thrust generating portion, and the fluid leaking from the first cylinder chamber to the second cylinder chamber when the mover reciprocates is opposite to the moving direction of the thrust generating portion. The electromagnetically driven pump according to claim 1, wherein the second cylinder chamber escapes through a through hole.   The mover shaft is formed with communication holes perpendicular to the axial direction on both sides of the thrust generating portion, and thrusts the fluid leaked from the first cylinder chamber to the second cylinder chamber when the mover reciprocates. 2. The electromagnetically driven pump according to claim 1, wherein the one communicating hole through which the generating portion moves escapes from the other communicating hole into the second cylinder chamber on the opposite side through the hollow shaft hole.   A third valve is provided in the suction side opening of the mover shaft to prevent the fluid filled in the shaft hole from moving and closing the suction valve when the mover shaft moves toward the discharge side. The electromagnetically driven pump according to claim 4.   The fluid leaked from the first cylinder chamber to the second cylinder chamber when the mover reciprocates is transferred to the gap formed between the thrust generating portion and the inner wall surface of the second cylinder chamber, the thrust generating portion. A combination of at least any two of a through hole along the axial direction and a communicating hole formed on both sides of the thrust generating portion on the mover shaft and perpendicular to the axial direction is allowed to escape into the second cylinder chamber on the opposite side. Item 2. An electromagnetically driven pump according to item 1.

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