WO2018008245A1

WO2018008245A1 - Tube pump

Info

Publication number: WO2018008245A1
Application number: PCT/JP2017/016890
Authority: WO
Inventors: 裕之村岡
Original assignee: 株式会社コガネイ
Priority date: 2016-07-05
Filing date: 2017-04-28
Publication date: 2018-01-11
Also published as: JPWO2018008245A1; JP6709795B2; KR20190022268A; CN208503010U; TW201802356A; KR102267227B1; TWI722214B

Abstract

The tube pump comprises a metallic pump case 21 and a flexible tube 23 in such a manner that a pump chamber 24 is expanded/contracted by an indirect medium supplied to a drive chamber 25. Resin annular blocks 26 are fitted to the inner side of respective end parts of the flexible tube 23, and resin flanges 31 are welded to the outer side of the respective end parts of the flexible tube 23. Metallic fastening rings 34 are fastened to the pump case 21 by means of screw members 35, and a compressive force is applied to the flanges 31 between the pump case 21 and the fastening rings 34.

Description

Tube pump

The present invention relates to a tube pump for applying a liquid to an object to be coated.

There is a tube pump as a pump for applying a liquid such as a photoresist solution to a semiconductor wafer as an object to be coated. The tube pump is a pump in which an elastic deformation portion of a flexible tube is expanded and contracted in a radial direction to perform a pump operation, and is also referred to as a tube diaphragm pump. This type of pump has a pump case and a flexible tube built into the pump case, and the inside of the pump case is divided into an inner pump chamber and an outer drive chamber by an elastic deformation portion of the flexible tube. Is done. When an indirect medium made of an incompressible fluid is supplied to the drive chamber, the elastic deformation portion contracts. On the other hand, when the indirect medium is discharged from the driving chamber, the elastic deformation portion expands.

In a pump using such a flexible tube, when the elastically deforming portion contracts, a force is applied to both ends of the flexible tube in the direction of being drawn into the pump case. For this reason, it is necessary to firmly fasten both ends of the flexible tube to the pump case.

In the tube pump described in Patent Document 1, a tapered fitting surface is provided at the end of the cylinder, and the end of the flexible tube is fastened to the fitting surface by an adapter. The chemical solution supply device described in Patent Document 2 has a fastening member that sandwiches an end of a flexible tube with a pump case, and press-fits a wedge member into a tapered groove provided in the fastening member. Thus, the end of the flexible tube is fastened to the pump case. Patent Document 3 discloses a liquid ejecting apparatus having a rubber tube disposed inside an outer shell container and a silicon tube disposed inside the rubber tube, and the silicon tube is a small diameter portion of the end member. And a collar attached to the end member.

JP 11-117872 A JP 2010-380007 A JP-A-9-303267

When the discharge pressure of the liquid discharged from the pump chamber in the flexible tube is increased or the discharge capacity is increased, when the elastic deformation portion of the flexible tube contracts, both ends of the flexible tube A large force is applied in the direction of being drawn into the pump case. For this reason, the fastening force of a flexible tube cannot be raised in the structure which fastens the edge part of a flexible tube to a pump case by applying radial fastening force like the conventional pump. Therefore, it is impossible to increase the discharge pressure of the liquid from the pump chamber or increase the discharge capacity.

Further, in order to apply a radial fastening force to the end portion of the flexible tube, a collar for press-fitting a wedge member into the groove of the fastening member or fastening the end portion of the flexible tube as in the past. Must be fastened to the end member, and the structure for fastening the flexible tube becomes complicated.

An object of the present invention is to provide a tube pump having a simple structure capable of firmly fastening an end portion of a flexible tube to a pump case.

The tube pump of the present invention includes a metal pump case and a flexible tube that is incorporated in the pump case and partitions the inner pump chamber and the outer drive chamber, and is supplied to the drive chamber. A tube pump in which the pump chamber is expanded and contracted by a compressible indirect medium, and an annular block made of resin fitted inside an end of the flexible tube, and an end of the flexible tube A resin flange that is welded to the outside of the pump case and attached to a mounting hole provided at an end of the pump case, and sandwiches the end of the flexible tube with the annular block, and a screw member on the pump case And a metal fastening ring that applies a compressive force in the direction of the central axis to the flange with the contact surface provided on the pump case.

Both end portions of the flexible tube are sandwiched between the annular block and the flange, and the flexible tube is welded to the flange and integrated with the flange. Therefore, even if a large force is applied in the direction in which the both ends of the flexible tube are pulled into the pump case due to the elastic deformation of the flexible tube in the radial direction, There is no deviation from the flange. By welding the flexible tube to the flange, the structure for fastening the both ends of the flexible tube is simplified, and the tube pump can be simplified.

Since the resin flange is fastened so as to be sandwiched between the metal pump case and the metal fastening ring, the flange is elastically deformed by the fastening force, thereby improving the sealing performance between the indirect medium and the liquid. it can.

It is a front view which shows the tube pump which is one Embodiment. It is a right view of FIG. FIG. 3 is a partially omitted enlarged sectional view of the outflow side and the inflow side of the pump unit shown in FIGS. 1 and 2. It is an expanded sectional view which shows the one end part of the pump unit before assembly completion. It is an expanded sectional view showing one end part of pump unit 11 which is other embodiments.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, the tube pump 10 includes a pump unit 11 and a drive unit 12. The pump unit 11 is provided with an inflow side joint 13a and an outflow side joint 13b. The tube pump 10 is mounted on a support base (not shown) such that the inflow side joint 13a faces downward and the outflow side joint 13b faces upward. A liquid container 14 containing a liquid such as a resist solution is connected to the inflow side joint 13 a by the inflow side flow path 15. An applicator 16 for applying a liquid to an object to be applied is connected to an outflow side joint 13b by an outflow side channel 17.

When the pump unit 11 is driven by the drive unit 12, the liquid in the liquid container 14 is supplied toward the applicator 16. In order to allow the flow of liquid from the liquid container 14 toward the pump unit 11 and prevent the flow in the reverse direction, a check valve 18 is provided in the flow path 15 on the inflow side. In order to allow the flow of liquid from the pump unit 11 toward the applicator 16 and prevent the reverse flow, a check valve 19 is provided in the flow path 17 on the outflow side.

As shown in FIG. 3, the pump unit 11 has a metal pump case 21. Two mounting holes 29 and one through hole 22 are provided in the pump case 21. The cross section of the attachment hole 29 and the through hole 22 is circular. The attachment holes 29 are provided so as to open at both end faces of the pump case 21 facing each other. The through hole 22 has an inner diameter smaller than that of the attachment hole 29 and penetrates between the attachment holes 29 at both ends. The central axis of the two mounting holes 29 and the central axis of the through hole 22 are the same. The step between the through hole 22 and the mounting hole 29 becomes an annular contact surface 30 perpendicular to the central axis of the mounting hole 29 and the through hole 22. In the positional relationship in the central axis direction, the side closer to the center of the through hole 22 in the central axis direction is the inner side in the axial direction of the central axis, and the side far from the center in the central axis direction of the through hole 22 is the outer side in the axial direction of the central axis. . On the outflow side of the pump unit 11 shown in FIG. 3, the outflow side joint 13b is outward in the axial direction, and the through hole 22 is inward in the axial direction. Similarly, on the inflow side of the pump unit 11 shown in FIG. 3, the inflow side joint 13a is axially outward and the through hole 22 is axially inward.

A flexible tube 23 made of fluororesin is incorporated into the through hole 22. The through hole 22 is partitioned into a pump chamber 24 inside the flexible tube 23 and a drive chamber 25 outside the flexible tube 23. When an indirect medium composed of an incompressible fluid such as a liquid is supplied to the drive chamber 25, the flexible tube 23 is deformed inward, the pump chamber 24 contracts, and the indirect medium is discharged from the drive chamber 25. The flexible tube 23 is deformed outward and the pump chamber 24 expands. Thus, the pump chamber 24 is expanded and contracted by the incompressible indirect medium supplied to the drive chamber 25.

A resin-made annular block 26 is fitted inside the both ends of the flexible tube 23. A communication hole 27 communicating with the pump chamber 24 is provided at an outer end portion of the annular block 26, that is, an end portion on the axially outer side of the central axis, at the radial center portion. The annular block 26 is provided with a tapered surface 28 whose inner diameter gradually decreases from the axially inner end of the central axis toward the communication hole 27.

An annular flange 31 made of resin is disposed in both the upper and lower mounting holes 29, and the gap between the flange 31 and the mounting hole 29 is sealed by a seal member 32. Each flange 31 is welded to the outer surface of both ends of the flexible tube 23. At both ends of the flexible tube 23, protruding end portions 23 b that protrude from the outer end surface in the central axis direction of the flange 31 to the outside of the drive chamber 25 are provided. The corner formed by the end surface of the flange 31 in the central axis direction and the protruding end 23 b of the flexible tube 23 is a welded portion 33, and each flange 31 and the flexible tube 23 are formed by the welded portion 33. Welded. The annular block 26 and the flange 31 are each formed of a fluororesin, like the flexible tube 23.

As shown in FIG. 3, the annular flange 31 is disposed outside the upper end portion and the lower end portion of the flexible tube 23, and the annular block 26 is disposed inside the upper end portion and the lower end portion of the flexible tube 23. The Thus, the annular flange 31 and the annular block 26 sandwich the flexible tube 23 between the upper end portion and the lower end portion.

A metal fastening ring 34 is fastened to both end faces of the pump case 21 by a plurality of screw members 35. When the fastening ring 34 is fastened to the pump case 21 by the screw member 35, a compressive force in the central axis direction is applied to the resin flange 31 between the metal pump case 21 and the metal fastening ring 34. Each flange 31 contracts in the central axis direction and expands in the radial direction. When the flange 31 is elastically deformed in this way, the outer peripheral surface of the flange 31 is pressed against the mounting hole 29, and the inner peripheral surface is pressed against the outer peripheral surface of the flexible tube 23. Since the outer peripheral surface of the flange 31 is pressed against the mounting hole 29 of the metal pump case 21, the sealing property between the two is enhanced. Since the annular block 26 is provided inside the flexible tube 23, the flexible tube 23 is deformed inward even when the inner peripheral surface of the flange 31 is pressed against the outer peripheral surface of the flexible tube 23. To be prevented. Therefore, the sealing performance between the annular block 26 and the flexible tube 23 and between the flexible tube 23 and the flange 31 is enhanced. As described above, the sealing performance between the pump chamber 24 and the drive chamber 25 is improved.

As described above, the compressive force in the central axis direction is applied to the resin-made flanges 31, and each flange 31 contracts in the central axis direction and expands in the radial direction. Before the fastening ring 34 is fastened to the pump case 21 so that the resin flange 31 contracts in the direction of the central axis due to the compressive force in the central axis direction, the flange 31 is pumped as shown in FIG. It protrudes outward in the central axis direction from the end surface 21 a of the case 21. Therefore, there is a step G between the end surface 21 a and the flange 31, and when the fastening ring 34 is brought into contact with the flange 31, a gap due to the step G is provided between the fastening ring 34 and the pump case 21. As described above, the fastening ring 34 is fastened to the pump case 21 by the screw member 35 in a state where the gap due to the step G is provided between the fastening ring 34 and the pump case 21. As a result, the flange 31 is compressed and deformed by the tightening force of the screw member 35, the end surface 21a of the pump case 21 is brought into close contact with the fastening ring 34, and the length in the central axis direction of the step G becomes zero. In this way, the compressive force in the central axis direction is applied to the resin flange 31, and the flange 31 contracts in the central axis direction and expands in the radial direction. The step G ensures the expansion and deformation of the flange 31 in the radial direction.

In order to provide the above-described step G, the length in the central axis direction of the flange 31 before assembly is larger than the length A in the central axis direction between the contact surface 30 of the pump case 21 and the end surface 21a of the pump case 21. B is long. FIG. 4 shows a state before the fixing ring 41, the end plate 46, and the joint 13b are attached. FIG. 4 shows one end of the pump unit before completion of assembly, and the other end is the same.

The positioning protrusions 36 are provided on the radially outer peripheral portions of the outer end portions of the respective annular blocks 26, and the positioning protrusions 36 protrude radially outward. A stopper 37 that comes into contact with the protrusion 36 is provided on the radially inner side of the fastening ring 34. When the protrusion 36 contacts the stopper 37, the annular block 26 is positioned at a predetermined position in the central axis direction with respect to the pump case 21. Since both ends of the flexible tube 23 are sandwiched between the annular block 26 and the flange 31, the flexible tube 23 is positioned at a predetermined position in the central axis direction. Furthermore, since the outer surfaces of both end portions of each flange 31 and the flexible tube 23 are welded, the position of the flexible tube 23 in the central axis direction is firmly positioned. Between the both ends of the flexible tube 23 sandwiched between the annular block 26 and the flange 31 constitutes an elastic deformation portion 23 a of the flexible tube 23.

The claw portion 38 is annularly provided on the contact surface 30 of the pump case 21, and the claw portion 38 projects from the contact surface 30 in the central axis direction. Therefore, when a fastening force is applied to the flange 31 from the fastening ring 34, the claw portion 38 bites into the inner end surface of the flange 31 disposed in the mounting hole 29, that is, the axially inner end surface of the central axis, and the drive chamber 25 sealability is improved. Further, the protrusion 39 is provided in an annular shape on the inner end surface of the inner peripheral surface of the flange 31, that is, on the end portion on the axially inner side of the central axis. As described above, when the fastening ring 34 is fastened to the pump case 21 by the screw member 35, the resin flange 31 is disposed in the central axis direction between the metal pump case 21 and the metal fastening ring 34. Fastening force is applied. Then, each flange 31 contracts in the central axis direction and expands in the radially outward direction, and also expands in the radially inward direction, thereby reducing the inner diameter. Thereby, the protrusion 39 bites into the outer peripheral surface of the flexible tube 23, and the sealing performance of the pump chamber 24 and the drive chamber 25 is improved.

An annular fixing ring 41 is attached to each fastening ring 34 by a plurality of screw members 42. Each fixing ring 41 has an abutting surface 43 that contacts the outer end surface of the annular block 26, and a fitting hole 45 that fits to the outer peripheral surface of the annular projecting portion 44 provided in the annular block 26. . An end plate 46 is attached to the outer surface of the fixing ring 41 by a plurality of screw members 47, and a communication hole 48 communicating with the pump chamber 24 is provided in the end plate 46. The fitting portion 49 is provided on the inner surface of the end plate 46 so as to protrude in the central axis direction, and the fitting portion 49 is fitted to the inner peripheral surface of the annular protruding portion 44 of the annular block 26.

The outflow side joint 13b is fixed to the end plate 46 on the upper end side by a plurality of screw members 50, and the outflow side flow path 17 is connected to the joint 13b. The joint 13a on the inflow side is fixed to the end plate 46 on the lower end side by the screw member 50, and the flow path 15 on the inflow side is connected to the joint 13a. As shown in FIG. 3, the inflow side end and the outflow side end of the pump unit 11 have the same structure.

In order to assemble the pump unit 11 having the above-described structure, the flanges 31 are disposed in the upper and lower mounting holes 29 of the pump case 21, and the flexible tube 23 is disposed inside the flange 31. Each flange 31 is welded to the end of the flexible tube 23, and the upper and lower flanges 31 and the flexible tube 23 are joined and integrated by the welded portion 33. Next, the fastening rings 34 are disposed on both end surfaces of the pump case 21, and the annular blocks 26 are inserted into both end portions of the flexible tube 23. FIG. 4 shows a state in which one fastening ring 34 is disposed on one end surface of the pump case 21 and one annular block 26 is inserted into one end portion of the flexible tube 23.

When the fastening ring 34 is fastened to the pump case 21 by the screw member 35, the resin flange 31 is fastened in a state of being fastened between the metal fastening ring 34 and the pump case 21, respectively. Further, the inflow side joint 13 a and the outflow side joint 13 b are attached to both ends of the pump case 21 via the fixing ring 41 and the end plate 46.

As shown in FIGS. 1 and 2, the drive unit 12 includes a unit housing 52 to which an electric motor 51 is attached, and a cylinder in which a piston is reciprocally movable in the axial direction is disposed inside the unit housing 52. Is provided. A ball screw screwed to the piston is driven by the electric motor 51, and the piston is driven by the electric motor 51. An indirect medium is filled in the pressure chamber partitioned by the cylinder and the piston, and the pressure chamber communicates with the drive chamber 25 through a flow path. Therefore, when the indirect medium in the pressure chamber is supplied to the drive chamber 25 by driving the piston, the elastic deformation portion 23a of the flexible tube 23 is deformed radially inward, and the pump chamber 24 contracts. On the other hand, when the indirect medium in the drive chamber 25 is discharged from the drive chamber 25, the elastic deformation portion 23a of the flexible tube 23 is deformed radially outward, and the pump chamber 24 expands.

When the pump chamber 24 expands, the liquid in the liquid container 14 shown in FIG. 1 passes through the check valve 18 and is supplied into the pump chamber 24. At this time, the check valve 19 prevents the back flow of the liquid in the flow path 17. On the other hand, when the pump chamber 24 contracts, the liquid in the pump chamber 24 passes through the check valve 19 and is supplied to the applicator 16. At this time, the check valve 18 prevents the liquid in the pump chamber 24 from flowing back toward the liquid container 14.

When the elastic deformation portion 23 a of the flexible tube 23 contracts, a force in a direction of being drawn into the pump case 21 is applied to both ends of the flexible tube 23. However, since both the projecting end portions 23b of the flexible tube 23 are joined to the flange 31 by the welded portion 33, even if the elastically deforming portion 23a is greatly deformed, the occurrence of displacement of both end portions of the flexible tube 23 is prevented. Is prevented. Thus, by welding the flexible tube 23 to the flange 31, the pump unit 11 can have a simple structure. When the flange 31 and the flexible tube 23 are made of the same type of resin material, the bonding strength between the flange 31 and the flexible tube 23 by the welded portion 33 can be increased.

When the resin flange 31 is tightened between the metal pump case 21 and the metal fastening ring 34, the flange 31 is elastically deformed in the central axis direction and the radial direction. Then, since the outer peripheral surface of the flange 31 is pressed against the mounting hole 29 of the metal pump case 21, the sealing performance between the two is enhanced. Since the inner peripheral surface of the flange 31 is deformed radially inward, the sealing performance between the annular block 26 and the flexible tube 23 and between the flexible tube 23 and the flange 31 is enhanced. In this way, leakage of the indirect medium from the pump unit 11 can be reliably prevented over a long period of time.

FIG. 5 is an enlarged cross-sectional view showing one end portion of a pump unit 11 according to another embodiment. In FIG. 5, members having commonality with the above-described pump unit 11 are denoted by the same reference numerals. .

As shown in FIG. 5, a fitting hole 55 having a diameter smaller than that of the mounting hole 29 and larger than that of the through hole 22 is provided between the through hole 22 and the mounting hole 29, and the contact surface 30 is connected to the mounting hole 29. It is formed between the fitting hole 55. An annular protrusion 56 protrudes inward in the central axis direction from the end face of the flange 31 that is in contact with the drive chamber 25 and is provided integrally with the flange 31. Further, a metal auxiliary ring 57 is disposed on the inner peripheral surface of the annular protrusion 56.

Thus, the annular protrusion 56 is sandwiched between the inner peripheral surface of the fitting hole 55 and the outer peripheral surface of the auxiliary ring 57. Therefore, a radial compressive force by the fitting hole 55 and the auxiliary ring 57 of the pump case 21 is applied to the annular protrusion 56. As a result, the annular protrusion 56 is brought into close contact with the fitting hole 55, and is elastically deformed radially outward and elastically deformed in the central axis direction. Even if the annular protrusion 56 is elastically deformed in the central axis direction, the length C of the fitting hole 55 in the central axis direction is the annular protrusion so that the tip surface of the annular protrusion 56 does not hit the step surface 58 provided in the pump case 21. Longer than 56 lengths. The fitting hole 55, the annular protrusion 56, and the auxiliary ring 57 are designed so that an appropriate compressive force is applied to the annular protrusion 56.

Thus, the sealing performance between the outer peripheral surface of the annular protrusion 56 and the fitting hole 55 is enhanced by the auxiliary ring 57. In the tube pump shown in FIG. 5, the flange 31 and the mounting hole 29 are sealed by the elastic force applied by the flange 31, and the space between the annular protrusion 56 of the flange 31 and the fitting hole 55 is an auxiliary. The ring 57 is sealed by a compressive force applied to the annular protrusion 56 radially outward.

FIG. 5 shows the structure of one end of the pump unit 11, but the other end has the same structure.

The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the scope of the invention.

The tube pump of the present invention can be applied as a pump for applying a liquid such as a photoresist solution to an object to be coated such as a semiconductor wafer.

Claims

A metal pump case, and a flexible tube incorporated in the pump case and partitioning the inner pump chamber and the outer drive chamber, and the incompressible indirect medium supplied to the drive chamber A tube pump in which the pump chamber is expanded and contracted,
A resin-made annular block fitted inside the end of the flexible tube;
A resin flange welded to the outside of the end of the flexible tube and attached to a mounting hole provided at the end of the pump case, and sandwiching the end of the flexible tube with the annular block When,
A metal fastening ring that is fastened to the pump case by a screw member and applies a compressive force in a central axis direction to the flange between the pump case and a contact surface provided on the pump case;
Having a tube pump.
2. The tube pump according to claim 1, wherein an annular protrusion projecting inward in the central axis direction from an end face of the flange in contact with the drive chamber, and a fitting hole having a smaller diameter than the mounting hole provided at an end of the pump case. And a metal auxiliary ring disposed on the inner peripheral surface of the annular protrusion,
A tube pump that applies a compressive force in a radial direction to the annular protrusion by the metal auxiliary ring and the pump case.
The tube pump according to claim 1 or 2, wherein the flexible tube has a protruding end portion that protrudes from the end surface of the flange to the outside of the drive chamber,
The tube pump which provided the welding part in the corner | angular part formed by the end surface of the said flange and the outer peripheral surface of the said protrusion end part of the said flexible tube.
The tube pump according to any one of claims 1 to 3, wherein the length of the flange in the central axis direction before being assembled to the pump case is the contact surface of the pump case with which an end surface of the flange contacts. A tube pump longer than the length in the central axis direction between the pump case and the end face of the pump case.
The tube pump according to any one of claims 1 to 4, wherein a claw portion that bites into the flange is provided on the contact surface.
5. The tube pump according to claim 1, wherein a positioning protrusion is provided on the annular block, and a stopper that contacts the positioning protrusion is provided on the fastening ring.
The tube pump according to any one of claims 1 to 6, wherein a projection that bites into the outer peripheral surface of the flexible tube is provided on the inner peripheral surface of the flange.