JP2007071070A - Diaphragm pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a four-valve diaphragm pump having less possibility of liquid leakage. <P>SOLUTION: The diaphragm pump is provided with an upper housing, a pumping chamber plate, a diaphragm and a lower housing which are stacked in order. A pumping chamber forming recess to form one side pumping chamber facing the diaphragm in the lower housing single structure, an inlet port having a first inlet-side check valve, and a discharge port having a first discharge-side check valve communicating with the pumping chamber forming recess are formed in the lower housing. The pumping chamber forming recess to form the other pumping chamber facing the diaphragm, a second inlet-side check valve, and a second discharge-side check valve are formed in the pumping chamber plate. An inlet-side flow passage between the plates and a discharge-side flow passage between the plates branched from the inlet port and discharge port, respectively, of the lower housing and connected to the second inlet-side check valve and the second discharge side valve are formed between the upper housing and the pumping chamber plate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a diaphragm pump.

The diaphragm pump forms a pump chamber (variable volume chamber) by the diaphragm, and a pair of check valves (inlet side check allowing fluid flow to the pump chamber) in a pair of flow paths connected to the pump chamber. A discharge-side check valve that allows fluid flow from the valve and the pump chamber. When the diaphragm is vibrated, the volume of the pump chamber changes, and the suction side check valve opens in the stroke when the volume increases, and the discharge side check valve opens in the stroke when the volume decreases. It is done. The diaphragm is made of an elastic (vibrating) material such as rubber or a piezoelectric vibrator.
Japanese Patent Laid-Open No. 2001-193656

  As described above, this diaphragm pump repeats the operation of opening the suction side check valve in the stroke in which the volume of the pump chamber is expanded and opening the discharge side check valve in the stroke in which the volume is reduced. Is inevitable.

  The present applicant has proposed a diaphragm pump in which the pulsation at the discharge port is a problem and the cycle of the pulsation is halved (Japanese Patent Application No. 2004-154991). In this diaphragm pump, a pump chamber is formed above and below the diaphragm by the diaphragm, while a single suction port and a single discharge port are provided, and each suction port is provided between a pair of pump chambers and a suction port. Provided with first and second suction-side check valves that allow fluid flow from one to the pair of pump chambers but not in the opposite direction, respectively, between the pair of pump chambers and the discharge port. Are provided with first and second discharge-side check valves that allow fluid flow from the pump chamber to the discharge port but do not allow fluid flow in the opposite direction (four-valve diaphragm pump).

  Japanese Patent Application No. 2004-154991 proposed a pump structure that can further reduce the thickness of the four-valve diaphragm pump. However, the pump structure of the example is a structure in which an umbrella is attached to the suction port and the discharge port formed in the upper and lower housings, respectively, and then a separate lid body that forms a flow path is bonded. For bonding, for example, highly reliable laser welding can be used. However, in pumps that handle liquids, liquid leakage may occur due to changes over time due to long-term use, and it is difficult to obtain perfect reliability. It turned out.

  Accordingly, an object of the present invention is to obtain a four-valve diaphragm pump that is less likely to cause liquid leakage.

  In the present invention, a pump chamber is formed above and below the diaphragm by a diaphragm to which vibration is applied, and a fluid from the suction port to the pair of pump chambers is formed between the pair of pump chambers and a single suction port. First and second suction-side check valves are provided that allow flow but do not allow fluid flow in the opposite direction, and discharge from the pair of pump chambers between the pair of pump chambers and a single discharge port, respectively. A diaphragm pump provided with first and second discharge side check valves that allow fluid flow to the port but not reverse fluid flow, the upper housing, the pump chamber plate, the diaphragm, and The lower housing is provided with a pump chamber forming recess that forms one pump chamber facing the diaphragm, and the pump housing forming recess. A suction port having a first suction-side check valve and a discharge port having a first discharge-side check valve are formed, and the other pump chamber is formed on the pump chamber plate so as to face the diaphragm. A pump chamber forming recess, a second suction side check valve and a second discharge side check valve are provided, and branch from the upper housing suction port and the discharge port between the upper housing and the pump chamber plate. Thus, the inter-plate suction side flow path and the inter-plate discharge side flow path connected to the second suction side check valve and the second discharge side check valve are formed.

  The inter-plate suction side flow path and the inter-plate discharge side flow path are preferably formed in a liquid-tight manner between the pump chamber plate and the upper housing via a seal ring.

  One end of the inter-plate suction side flow path and the inter-plate discharge side flow path are communicated with a second suction side check valve and a second discharge side check valve formed in the pump chamber plate, respectively. Each of the end portions preferably communicates with the respective branch flow paths from the suction port and the discharge port that open to the lower housing.

  For example, if the seal ring has an oval shape, the flow path can be easily formed.

  The first suction side check valve and the first discharge side check valve of the lower housing are formed as a check valve unit separately on the suction side and the discharge side of the lower housing, and the suction side and the discharge side It is desirable to join the check valve unit to the pump chamber side opening ends of the suction port and the discharge port. The first suction side check valve unit and the first discharge side check valve unit can be provided on the same substrate.

  If the suction port and the discharge port of the lower housing are formed so as to protrude in a direction parallel to the plane direction in the free state of the diaphragm and in parallel with each other, it is suitable for reducing the thickness of the diaphragm pump.

  In any embodiment, it is desirable that the check valve is composed of an umbrella. Moreover, it is practical that the diaphragm is composed of a piezoelectric vibrator or an electrostrictive vibrator. A bimorph type piezoelectric vibrator is particularly preferable.

  According to the present invention, it is possible to obtain a four-valve diaphragm pump that is less likely to cause liquid leakage.

  First, the operation principle of the 4-valve diaphragm pump will be described with reference to FIG. This diaphragm pump includes an upper housing 10, a lower housing 20, a piezoelectric vibrator (diaphragm) 30, and four umbrellas (check valves) 11, 12, 21, and 22 as basic components. A pump chamber (variable volume chamber) 13 and a pump chamber (variable volume chamber) 23 are formed between the upper housing 10 and the piezoelectric vibrator 30, and between the lower housing 20 and the piezoelectric vibrator 30, respectively. The single suction port 31 communicates with the suction side channels 14H and 24H, the suction side channel 14H communicates with the pump chamber 13 via the suction side umbrella 11, and the suction side channel 24H communicates with the suction side umbrella. It communicates with the pump chamber 23 via 21. The single discharge port 32 communicates with the discharge side flow paths 15D and 25D, the discharge side flow path 15D communicates with the pump chamber 13 via the discharge side umbrella 12, and the discharge side flow path 25D discharges. The pump chamber 23 communicates with the side umbrella 22.

  In the four-valve diaphragm pump, when the piezoelectric vibrator 30 is elastically deformed (vibrated) in the forward and reverse directions, the volume of one of the pump chambers 13 and 23 increases and the other volume decreases. The stroke in which the volume of the pump chamber 13 is increased is the stroke in which the volume of the pump chamber 23 is decreased. Since the volume of the pump chamber 13 is increased, the suction side umbrella (suction side check valve) 11 is opened and pumped from the suction port 31. Since the fluid flows into the chamber 13 and the volume of the pump chamber 23 decreases, the fluid in the pump chamber 23 opens the discharge-side umbrella (discharge-side check valve) 22 and flows out to the discharge port 32. Conversely, the stroke in which the volume of the pump chamber 13 decreases is a stroke in which the volume of the pump chamber 23 increases. Since the volume of the pump chamber 23 increases, the suction side umbrella (suction side check valve) 21 opens and the suction port 31 opens. Then, the fluid flows into the pump chamber 23 and the volume of the pump chamber 13 decreases, so that the fluid in the pump chamber 13 opens the discharge-side umbrella (discharge-side check valve) 12 and flows out to the discharge port 32. Therefore, the pulsation cycle at the discharge port 32 can be shortened (halved compared to the case where the pump chamber is formed only on one of the upper and lower sides of the piezoelectric vibrator 30).

  In the present embodiment, the four-valve diaphragm pump having the above operation principle is realized with a liquid leakage prevention structure that does not cause liquid leakage, and an embodiment thereof will be described with reference to FIGS. The diaphragm pump has a pump chamber plate 40 sandwiched between the upper housing 10 and the piezoelectric vibrator 30 in addition to the upper housing 10, the lower housing 20, and the piezoelectric vibrator 30, and is flat as a whole. It has a rectangular parallelepiped shape. The upper housing 10, the lower housing 20, and the pump chamber plate 40 are all formed from a molded product of a resin material.

  The lower housing 20 is a flat rectangular parallelepiped member having the largest and complicated shape among these molded products, and is formed with a pump chamber forming concave portion 20a opened on a surface facing the piezoelectric vibrator 30. A suction port 31 and a discharge port 32, which are integrally formed and parallel to each other, are projected and formed from one of the four flat peripheral surfaces (see FIGS. 1 to 5). The lower housing 20 is formed with a suction side flow path 24H communicating with the suction port 31 and a discharge side flow path 25D communicating with the discharge port 32. The suction side flow path 24H and the discharge side flow path 25D are formed. At the inner end, flow passage expanding portions 24Ha and 25Da communicating with the pump chamber forming recess 20a are formed. Valve receiving recesses 24Hb and 25Db are formed at the ends of the flow passage expanding portions 24Ha and 25Da on the pump chamber forming recess 20a side.

  A suction side umbrella unit (suction side check valve unit) 21U and a discharge side umbrella unit (discharge side check valve unit) 22U are bonded and fixed to the valve receiving recesses 24Hb and 25Db, respectively. The suction-side umbrella unit 21U and the discharge-side umbrella unit 22U have the same structure except for the mounting direction, and the peripheral plate is a unit plate having an adhesive portion 21b (adhesive portion 22b) with the valve receiving concave portion 24Hb (valve receiving concave portion 25Db). An umbrella mounting hole 21c (umbrella mounting hole 22c) is formed at the center of 21a (unit plate 22a), and a plurality of flow path holes 21d (flow path holes 22d) are formed at the periphery of the umbrella mounting hole 21c (umbrella mounting hole 22c). ) Is formed. The umbrella portion 21g (umbrella portion 22g) of the umbrella 21f (umbrella 22f) in which the central shaft 21e (center shaft 22e) is mounted in the umbrella mounting hole 21c (umbrella mounting hole 22c) is normally the flow path hole 21d (flow path hole 22d). When a pressure of a specified value or more is applied to the umbrella part 21g (umbrella part 22g) from the channel hole 21d (channel hole 22d) side, the umbrella part 21g (umbrella part 22g) is elastically deformed and the channel hole 21d. (Flow channel hole 22d) is opened. The suction-side umbrella unit 21U and the discharge-side umbrella unit 22U have their adhesive portions 21b (adhesive portions 22b) bonded and fixed to the valve receiving recesses 24Hb and 25Db with the front and back sides reversed, and the suction-side umbrella unit 21U has a suction port 31. From the pump chamber forming recess 20a (pump chamber 23) to the discharge port 32, the discharge-side umbrella unit 22U permits fluid flow from the pump chamber to the pump chamber forming recess 20a (pump chamber 23) but not vice versa. Allow fluid flow but not vice versa. The unit plates 21a and 22a of the suction-side and discharge-side umbrella units 21U and 22U may be a single substrate.

  The lower housing 20 does not require a separate lid, and the lower housing 20 is a single unit between the suction port 31 and the pump chamber forming recess 20a and between the discharge port 32 and the pump chamber forming recess 20a. A suction side flow path 24H and a discharge side flow path 25D which are closed in between are formed. The lower housing 20 is also formed with a seal ring groove 20b positioned around the pump chamber forming recess 20a. The seal ring groove 20b has a deformed D shape having a large arc portion 20b1 formed of a part of a circle exceeding a semicircle, and a straight portion 20b2 connecting both ends of the large arc portion 20b1 with a straight line. .

  The suction-side umbrella unit 21U and the discharge-side umbrella unit 22U, that is, the valve receiving recesses 24Hb and 25Db (umbrella portions 21g and 22g) are inclined (non-parallel) with respect to the plane of the piezoelectric vibrator 30. The direction of this inclination is a plane that includes the axis of the suction port 31 (discharge port 32) and is orthogonal to the piezoelectric vibrator 30. In the plane, the depth of the suction port 31 (discharge port 32) increases toward the piezoelectric portion. This is a direction away from the transducer 30 and approaching the front. When the suction-side umbrella unit 21U and the discharge-side umbrella unit 22U are inclined as described above, the lower housing 20 can be thinned without sacrificing the flow path cross-sectional areas of the suction port 31 and the discharge port 32.

  That is, as shown in FIG. 4, the surface of the valve receiving recess 24Hb (the unit plate 21a (umbrella 21g) of the suction side umbrella unit 21U) and the plane in the free state of the piezoelectric vibrator 30 are non-parallel, An angle α is formed. That is, the flow path at the suction side check valve 21 is not orthogonal to the piezoelectric vibrator 30. On the other hand, the axis of the suction port 31 (suction side flow path 24H) is parallel to the plane of the piezoelectric vibrator 30. The direction of the angle α is such that the unit plate 21a (umbrella 21g) of the suction-side umbrella unit 21U is further away from the piezoelectric vibrator 30 toward the back of the suction port 31 (suction-side flow path 24H), and the piezoelectric vibrator is closer to the front. This is the direction approaching 30.

  Similarly, as shown in FIG. 5, the surface of the valve receiving recess 25Db (the unit plate 22a (umbrella portion 22g) of the discharge-side umbrella unit 22U) and the plane in the free state of the piezoelectric vibrator 30 are non-parallel. , Angle α. That is, the flow path at the discharge side check valve 22 is not orthogonal to the piezoelectric vibrator 30. On the other hand, the axis of the discharge port 32 (discharge side channel 25D) is parallel to the plane of the piezoelectric vibrator 30. The direction of the angle α is such that the unit plate 22a (umbrella 22g) of the discharge-side umbrella unit 22U is further away from the piezoelectric vibrator 30 toward the back of the discharge port 32 (discharge-side flow path 25D), and the piezoelectric vibrator toward the front. This is the direction approaching 30.

  The lower housing 20 is also formed with branch channels 24Hd and 25Dd that branch from the suction-side channel 24H and the discharge-side channel 25D and open to the pump chamber plate 40 side. The pump chamber plate 40 has communication holes 41 and 42 communicating with the branch flow paths 24Hd and 25Dd. The communication holes 41 and 42 are communicated between the upper housing 10 and the pump chamber plate 40. An inter-plate suction side flow path 14H and an inter-plate discharge side flow path 15D are formed. That is, the pump chamber plate 40 is formed with convex portions 41a and 42a that fit into the branch flow paths 24Hd and 25Dd, and communication holes 41 and 42 are formed at the centers of the convex portions 41a and 42a. 41b and 42b are O-rings that maintain liquid tightness between the branch flow paths 24Hd and 25Dd and the convex portions 41a and 42a (communication holes 41 and 42).

  The pump chamber plate 40 has a surface facing the piezoelectric vibrator 30 as a pump chamber forming recess 40a (FIGS. 2, 4, and 5), and has a suction side umbrella unit 21U and a discharge side umbrella at substantially the center thereof. A suction-side umbrella 11 and a discharge-side umbrella 12 corresponding to the unit 22U are mounted. In FIG. 2, the suction-side umbrella 11 and the discharge-side umbrella 12 are not drawn. That is, in the pump chamber plate 40, umbrella mounting holes 11a and 12a are formed at the vertical positions corresponding to the suction side umbrella unit 21U and the discharge side umbrella unit 22U, and a plurality of flow paths are formed around the periphery of the umbrella mounting holes 11a and 12a. Road holes 11b and 12b are formed. The suction-side umbrella 11 and the discharge-side umbrella 12 are umbrellas that block the central shaft 11c (central shaft 12c) mounted in the umbrella mounting hole 11a (umbrella mounting hole 12a) and the flow channel hole 11b (flow channel hole 12b) at all times. If the pressure more than a regulation value is applied to the umbrella part 11d (umbrella part 12d) from the channel hole 11b (channel hole 12b) side, the umbrella part 11d (umbrella part 12d) is provided. ) Is elastically deformed to open the channel hole 11b (channel hole 12b). The suction side umbrella 11 allows a fluid flow from the upper housing 10 side to the pump chamber forming recess 40a (pump chamber 13) and does not allow the opposite fluid flow. The discharge side umbrella 12 has a pump chamber forming recess 40a (pump). The fluid flow from the chamber 13) to the upper housing 10 side is allowed and the opposite fluid flow is not allowed.

  The upper housing 10 has substantially the same planar shape as the lower housing 20 so as to overlap the lower housing 20. The upper housing 10 is connected to the pump chamber plate 40 between the communication hole 41 and the suction-side umbrella 11. The recess 14Ha forms the inter-plate suction-side flow path 14H, the communication hole 42 and the discharge-side umbrella 12. And a recess 15Da for forming the inter-plate discharge-side flow path 15D (see FIGS. 2 and 4 to 6). Around the recesses 14Ha and 15Da, seal ring grooves 14Hc and 15Dc for fitting oval O-rings (seal rings) 14Hb and 15Db are formed. The upper housing 10 is also formed with a recess 10a (FIGS. 2 and 6) into which the pump chamber plate 40 is fitted.

  The pump chamber plate 40 and the upper housing 10 have a positioning fitting projection 40c and a fitting hole 10c (FIG. 1) that are fitted to each other with the oval O-rings 14Hb and 15Db fitted in the recesses 14Ha and 15Da, respectively. The liquid-tight plate 14H from the communication hole 41 to the suction-side umbrella 11 and the liquid-tight plate from the discharge-side umbrella 12 to the communication hole 42 are bonded by bonding them after fitting. The intermediate discharge side flow path 15D is formed. That is, the upper housing 10 and the pump chamber plate 40 are integrated in advance by fitting the plate 40 in the recess 10a, thereby forming the inter-plate suction side flow path 14H and the inter-plate discharge side flow path 15D which are closed between the two. To do. In other words, no lid member other than the upper housing 10 and the pump chamber plate 40 is required to form the inter-plate suction side flow path 14H and the inter-plate discharge side flow path 15D.

  As clearly shown in FIG. 7, the pump chamber plate 40 has a pump chamber forming recess 40a facing the piezoelectric vibrator 30 and corresponds to the seal ring groove 20b of the lower housing 20 (having the same shape in plan view). ) A seal ring groove 40b is formed. The seal ring groove 40b has a deformed D shape having a large arc portion 40b1 formed of a part of a circle exceeding a semicircle and a straight portion 40b2 connecting both ends of the large arc portion 40b1 with a straight line. .

The piezoelectric vibrator 30 can be either a unimorph type or a bimorph type. FIG. 8 to FIG. 10 are schematic views of an embodiment of the bimorph type proposed by the present applicant in Japanese Patent Application No. 2004-192383, and a circular shim 111 in the center portion and a piezoelectric body 112 laminated on the front and back sides thereof. It has. The shim 111 is made of a conductive metal thin plate material, for example, a stainless thin plate having a thickness of about 0.2 mm. The piezoelectric body 112 is made of, for example, PZT (Pb (Zr, Ti) O ₃ ) having a thickness of about 0.3 mm, and is polarized in the front and back directions. This polarization process is performed in the same direction in the pair of piezoelectric bodies 112 positioned on the front and back of the shim 111. That is, in FIG. 8, when the polarization direction of the pair of piezoelectric bodies 112 is represented by an arrow a or b, polarization processing in the same direction is performed in the thickness direction of the shim 111. In other words, the polarization characteristics of the pair of front and back piezoelectric bodies 112 in contact with the shim 111 have different polarities, and the exposed surfaces of the pair of piezoelectric bodies 112 have different polarities. When the polarization characteristics of the front and back piezoelectric bodies 112 are set in the same direction as described above, when the positive and negative voltages are alternately applied between the shim 111 and the exposed surfaces of the pair of piezoelectric bodies 112 on the front and back of the shim 111, the displacement of the shim 111 is changed. The amount can be increased.

  The surfaces of the pair of piezoelectric bodies 112 on the shim 111 side are bonded so as to be fully conductive with the shim 111, and a film electrode 113 is formed on the entire exposed surface opposite to the shim 111 side. . The film electrode 113 is formed, for example, by printing (screen baking) a conductive paste (silver paste).

  The power supply terminal 180 includes a pair of contacts 1811, a connection edge 1812 that connects the contacts 1811, and a wiring connection portion 1813. The pair of contacts 1811 and the connection edge 1812 are U-shaped. It has a cross section. The pair of contacts 1811 have the same shape having a substantially triangular plane that is wide on the side of the wiring connecting portion 1813 located outside the piezoelectric vibrator 30 and gradually narrows toward the center of the piezoelectric vibrator 30. There is no. That is, the contact 1811 has the narrowest width of the soldering portion 1131 with the film-like electrode 113 of the piezoelectric vibrator 30 and widens toward the outside of the piezoelectric vibrator 30.

  A wire connection protrusion 114 that protrudes in the radial direction and is formed on the shim 111 of the piezoelectric vibrator 30 extends between the pair of contacts 1811. The wiring connection protrusion 114 is formed with an insulating recess 1141 that secures a gap between the connection edge 1812 connecting the pair of contacts 1811.

  An annular spacer insulating ring 115 is positioned above and below the circular shim 111, and a strip-shaped insulating plate 1151 is provided between the pair of upper and lower spacer insulating rings 115 between the pair of contacts 1811 and the wiring connection protrusion 114. Extends to prevent a short circuit between the shim 111 and the power supply terminal 180. At the same time, the strip-shaped insulating plate material 1151 prevents the connection edge 1812 of the power supply terminal 180 from moving to the insulating recess 1141 side of the shim 111 and ensures insulation.

  The wiring connection projection 114 of the shim 111 is positioned on the outer side of the piezoelectric resonator 30 with respect to the insulating recess 1141 and symmetrically on both sides of the wiring connection projection 114 in the width direction. 1144 is formed, and a soldering through hole 1145 is formed inward of one lead wire latching recess 1143.

  A soldering through hole 1814 is formed in the wiring connection portion 1813 of the power supply terminal 180 so as to correspond to the soldering through hole 1145 of the wiring connection protrusion 114. The soldering through holes 1145 and 1814 have different plane positions, and lead wires 211 and 221 are soldered, respectively. The soldering through holes 1145 and 1814 can be thinned as a whole by increasing the soldering strength and changing the planar positions thereof. Further, the lead wires 211 and 221 are hooked to the lead wire latching recesses 1143 and 1144 to increase the resistance of the lead wires 211 and 221 from being pulled out.

  A PPS film (insulating film) 241 (FIG. 8) is bonded to the surface of the piezoelectric vibrator 30. The PPS film 241 has a radial tongue 241 a extending on the power supply terminal 180, and prevents the contact 1811 and the film electrode 113 of the piezoelectric vibrator 30 from being detached.

  According to the wiring structure around the wiring connection protrusion 114 and the power supply terminal 180 of the shim 111 described above, it is possible to reliably wire the shim 111 and the film electrode 113 without hindering the movement of the piezoelectric vibrator 30.

  As described above, the piezoelectric vibrator 30 having a planar circular shape as the basic shape is sandwiched between the pump chamber forming recess 20a of the lower housing 20 and the pump chamber forming recess 40a of the pump chamber plate 40, and the periphery thereof. The upper and lower sides are sealed by seal rings 16 and 26 to form pump chambers 13 and 23. The seal rings 16 and 26 have the same shape as the seal ring groove 20b of the lower housing 20 and the seal ring groove 40b of the pump chamber plate 40, and have a large arc portion 16a (large arc portion 26a) and a straight portion 16b (straight portion 26b). )have. The power supply terminal 180 of the piezoelectric vibrator 30 is located outside the seal rings 16 and 26, that is, outside the straight portion 16b (straight portion 26b). With this arrangement, the feed terminal 180 for the piezoelectric body 112 of the piezoelectric vibrator 30 can be prevented from intersecting the seal rings 16 and 26, and the seal rings 16 and 26 are not locally deformed. Can be improved.

  Further, the lower housing 20 and the upper housing 10 integrated in advance with the pump chamber plate 40 are fastened by fasteners (for example, bolts and nuts) with the piezoelectric vibrator 30 sandwiched between them as described above. Combined and united. Of course, an adhesive can be additionally used.

  The basic operation of the diaphragm pump having the above configuration is not different from the operation described in FIG. When an alternating electric field is applied between the power supply terminal 180 of the piezoelectric vibrator 30 and the shim 111 (wiring connection protrusion 114) to cause elastic deformation (vibration) in the forward and reverse directions, the volume of one of the pump chambers 13 and 23 increases. However, the volume of the other is reduced. In the stroke in which the volume of the pump chamber 13 is increased, the suction-side umbrella 11 is opened and fluid flows into the pump chamber 13 from the suction port 31. At the same time, the volume of the pump chamber 23 is decreased, so that the fluid in the pump chamber 23 is discharged. The side umbrella (unit) 22 is opened and flows into the discharge port 32. Conversely, in the stroke in which the volume of the pump chamber 13 decreases, the suction-side umbrella (unit) 21 opens and fluid flows into the pump chamber 23 from the suction port 31, and the volume of the pump chamber 13 decreases. Opens the discharge-side umbrella 12 and flows out to the discharge port 32.

The seal rings 16 and 26 in the above embodiment are non-circular, but circular seal rings (O-rings) may be used. Moreover, although the umbrella was illustrated as a check valve, it is also possible to use a check valve other than the umbrella. In the above embodiment, the piezoelectric vibrator is used as the diaphragm, but an electrostrictive vibrator may be used instead of the piezoelectric vibrator.

It is a perspective view of the disassembled state which shows one Embodiment of the diaphragm pump by this invention. It is sectional drawing of the same decomposition | disassembly state. It is a top view of a lower housing. It is sectional drawing which follows the IV-IV line of FIG. It is sectional drawing which follows the VV line of FIG. It is a top view by the side of the pump chamber plate of an upper housing. It is a top view by the side of the pump chamber formation recessed part of a pump chamber plate. It is an exploded perspective view of a bimorph type piezoelectric vibrator. It is a perspective view which shows the relationship between the same bimorph type piezoelectric vibrator and a deformation | transformation D type seal ring. It is a top view of the principal part. It is a conceptual diagram of a 4-valve diaphragm pump to which the present invention is applied.

Explanation of symbols

10 Upper housing 10c Fitting hole 11 Suction side umbrella (suction side check valve)
11a 12a Umbrella mounting hole 11b 12b Channel hole 11c 12c Center shaft 11d 12d Umbrella 12 Discharge side umbrella (discharge side check valve)
13 Pump chamber (variable volume chamber)
14H Inter-plate suction side channel 14Ha Recess 14Hb Oval O-ring (seal ring)
14Hc Seal ring groove 15D Inter-plate discharge side flow path 15Da Recess 15Db Oval O-ring 15Dc Seal ring groove 16 Seal ring 16a Large arc portion 16b Linear portion 20 Lower housing 20a Pump chamber forming recess 20b Seal ring groove 20b1 Large arc portion 20b2 Straight part 21 Suction side umbrella (suction side check valve)
21U Suction side umbrella unit (suction side check valve unit)
21a 22a Unit plate 21b 22b Adhesive part 21c 22c Umbrella mounting hole 21d 22d Channel hole 21e 22e Center shaft 21f 22f Umbrella 21g 22g Umbrella part 22 Discharge side umbrella (discharge side check valve)
22U discharge-side umbrella unit (discharge-side check valve unit)
23 Pump chamber (variable volume chamber)
24H Suction side flow path 24Ha Flow path expansion section 24Hb Valve receiving recess 24Hd Branch flow path 25D Discharge side flow path 25Da Flow path expansion section 25Db Valve reception recess 25Dd Branch flow path 26 Seal ring 26a Large arc portion 26b Linear portion 30 Piezoelectric vibrator (Diaphragm)
31 Suction port 32 Discharge port 40 Pump chamber plate 40a Pump chamber forming recess 40b Seal ring groove 40b1 Large arc portion 40b2 Straight portion 40c Positioning fitting protrusion 41 42 Communication hole 41a 42a Protruding portion 41b 42b O-ring 111 Shim 112 Piezoelectric body 180 Power supply Terminal 211 221 Lead wire

Claims (10)

Pump chambers are formed above and below the diaphragm by the diaphragm to which vibration is applied, and fluid flow from the suction port to the pair of pump chambers is allowed between the pair of pump chambers and a single suction port. First and second suction side check valves that do not allow fluid flow in the reverse direction are provided, and fluid flows from the pair of pump chambers to the discharge port between the pair of pump chambers and a single discharge port, respectively. A diaphragm pump provided with first and second discharge-side check valves that allow flow and do not allow fluid flow in the opposite direction,
An upper housing, a pump chamber plate, a diaphragm, and a lower housing, which are stacked in order,
The lower housing has a suction port having a pump chamber forming recess that forms one pump chamber facing the diaphragm, and a first suction-side check valve that communicates with the pump chamber forming recess. And a discharge port having a first discharge side check valve,
The pump chamber plate is provided with a pump chamber forming recess that forms the other pump chamber facing the diaphragm, a second suction side check valve, and a second discharge side check valve,
Between the upper housing and the pump chamber plate, the inter-plate suction side flow branched from the suction port and the discharge port of the lower housing and connected to the second suction side check valve and the second discharge side check valve. A diaphragm pump characterized by forming a passage and a discharge passage between plates. 2. The diaphragm pump according to claim 1, wherein the inter-plate suction side flow path and the inter-plate discharge side flow path are formed in a liquid-tight manner via a seal ring interposed between the pump chamber plate and the upper housing. pump. 3. The diaphragm pump according to claim 2, wherein one end portions of the inter-plate suction side flow path and the inter-plate discharge side flow path are respectively a second suction side check valve and a second discharge side reverse valve formed in the pump chamber plate. A diaphragm pump that communicates with the stop valve and that communicates with the respective branch flow paths from the suction port and the discharge port that open to the lower housing, respectively. 4. The diaphragm pump according to claim 2, wherein the seal ring has an oval shape. 5. The diaphragm pump according to claim 1, wherein the first suction-side check valve and the first discharge-side check valve provided in the lower housing are separate from the lower housing. Are formed as a suction check valve unit and a first check valve unit, and the first suction check valve unit and the first discharge check valve unit are provided on the pump chamber side opening of the suction port and the discharge port. Diaphragm pumps joined to each end. 6. The diaphragm pump according to claim 5, wherein the first suction side check valve unit and the first discharge side check valve unit are provided on the same substrate. The diaphragm pump according to any one of claims 1 to 6, wherein the suction port and the discharge port of the lower housing are formed so as to protrude in a direction parallel to a plane direction in a free state of the diaphragm and in parallel with each other. . The diaphragm pump according to any one of claims 1 to 7, wherein the check valve is an umbrella. 9. The diaphragm pump according to claim 1, wherein the diaphragm is a piezoelectric vibrator or an electrostrictive vibrator. 9. The diaphragm pump according to claim 1, wherein the diaphragm is a bimorph piezoelectric vibrator.

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