pinch valve

Abstract

The pinch valve (1) comprises: a tube body (3) made of elastic material, wherein a flow path is formed inside the tube body; a pushing part (4); a rod member (6) installed at the front end of the pushing part (4); and a connecting part (35) provided on the outer surface of the tube body (3) to connect the rod member (6) to the tube body (3) in a transverse arrangement; the pinch valve is configured such that the tube body (3) is deformed by pushing or releasing the pushing part (4) of the rod member (6), thereby opening or closing the flow path.

Description

Technical Field

[0001] This invention relates to pinch valves. Background Technology

[0002] A pinch valve is known, comprising: a valve section; a tube body having a flow path formed internally and housed within the valve section; a pressing section that deforms the tube body by pressing it or releasing the pressing to open or close the flow path; and a driving section that drives the pressing section (see, for example, Patent Document 1). In the pinch valve of Patent Document 1, the tube body is housed within a retaining member of the valve section. Annular flanges are formed at both ends of the tube body. Typically, the tube body is made of an elastic material such as rubber.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-211081 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Due to the continuous and repeated pressing and releasing of the pressure-pressing mechanism over many years, the pipe body experiences material deterioration. If the material deteriorates, even after the pressure is released following full closure achieved by the pressing mechanism, issues may arise such as the inner surfaces of the pipe body being firmly bonded together, the pipe body not fully recovering its shape, or plastic deformation. Consequently, problems such as incomplete opening and closing of the pinch valve and decreased responsiveness may occur.

[0008] The purpose of this invention is to provide a pinch valve that can reliably control opening and closing.

[0009] Methods used to solve problems

[0010] According to a technical solution of the present invention, a pinch valve is provided, characterized in that it comprises: a pipe body made of an elastic material and having a flow path formed therein; a pushing part; a rod member installed at the front end of the pushing part; and a connecting part provided on the outer surface of the pipe body, wherein the rod member is connected to the pipe body in a transverse arrangement relative to the pipe body; by pushing or releasing the pushing part of the rod member onto the pipe body, the pipe body is deformed, thereby opening or closing the flow path.

[0011] Alternatively, the aforementioned rod component can be a cylindrical component, with a snap-fit ​​recess at the front end of the aforementioned pressing portion capable of engaging the rod component in a snap-fit ​​manner. Alternatively, the aforementioned snap-fit ​​recess can be provided with a locking claw capable of engaging with the aforementioned rod component. The aforementioned rod component can also be formed to have the same length as the width of the deformed tube body when the clamp valve is fully closed.

[0012] Invention Effects

[0013] According to the technical solution of the present invention, a pinch valve is provided that can reliably control the opening and closing of the valve. Attached Figure Description

[0014] Figure 1 This is a longitudinal cross-sectional view of the pinch valve according to an embodiment of the present invention.

[0015] Figure 2 This is an enlarged longitudinal section view of the tube.

[0016] Figure 3 It is a three-dimensional view of the tube.

[0017] Figure 4 It is a three-dimensional diagram showing the assembly of the tube body and the pushing part.

[0018] Figure 5 This is a cross-sectional view of the tube.

[0019] Figure 6 This is a front view of the pressing part.

[0020] Figure 7 This is a cross-sectional view of the pressing section.

[0021] Figure 8 It is a longitudinal cross-sectional view showing the opening and closing of the flow path in the pipe. Detailed Implementation

[0022] The following is a reference to the appendix. Figure 1 The embodiments of the present invention will be described in detail below. In all the drawings, common reference numerals are assigned to the corresponding constituent elements.

[0023] Figure 1 This is a longitudinal cross-sectional view of the pinch valve 1 according to an embodiment of the present invention. The pinch valve 1 has a valve part 2, a tube body 3 (pipe) with a flow path formed inside and housed in the valve part 2, a push part 4 that opens or closes the flow path by deforming the tube body 3 by pushing or releasing the push part, a drive part 5 that drives the push part 4, and a cylindrical rod member 6 installed at the front end of the push part 4.

[0024] The drive unit 5 includes a cylinder 10, a piston 11 that slides within the cylinder 10, a base plate 12 opposite to the piston 11, a display 13, and a cap 14. The drive unit 5 is a pneumatic actuator that supplies compressed air into the cylinder 10 via an air port (not shown) or exhausts air from the cylinder 10, thereby raising and lowering the piston 11 and the pusher 4 within the cylinder 10. The drive unit 5 can be an electric actuator, or the pusher 4 can be raised and lowered manually by operating a handle or lever. The pusher 4 is mounted on the front end of the piston 11. As the piston 11 rises and falls, the display 13 mounted on the piston 11 appears and disappears relative to the cylinder 10. Therefore, by visually observing the appearance and disappearance of the display 13 via the cap 14, the position of the piston 11 can be determined, and thus the position of the pusher 4 can be determined, i.e., the opening and closing state of the pinch valve 1 can be controlled. To seal between components, pinch valve 1 has multiple O-rings (e.g., O-ring 15).

[0025] The valve part 2 has an integrally formed cylindrical retaining member 20 that can accommodate the tube body 3, connecting members 21 disposed at both ends of the retaining member 20, and cap nuts 22 screwed together with the connecting members 21 at both ends of the retaining member 20. The drive part 5 is mounted relative to the valve part 2, specifically relative to the retaining member 20, by screws (not shown). The tube body 3 has a cylindrical tube body 31 and annular flange portions 32 provided at both ends of the tube body 31, and a flow path is formed inside the tube body 3. With the connecting members 21 in close contact with the end faces of the flange portions 32 and the end faces of the retaining member 20, the cap nuts 22 are screwed relative to the retaining member 20.

[0026] The pinch valve 1, particularly the valve part 2, can be made entirely of a plastic material. For example, the cylinder 10 and base plate 12 are made of polypropylene (PPG) mixed with glass, the push part 4 and piston 11 are made of acetal resin (POM), the retaining part 20, the connecting part 21 and the cap nut 22 are made of polyvinyl chloride (U-PVC), the display 13 is made of acrylonitrile butadiene styrene (ABS), and the cap 14 is made of polycarbonate (PC). The tube body 3 is made of an elastic material such as rubber, for example, ethylene propylene diene monomer (EPDM) or fluororubber (FKM). The rod part 6 is made of metal or rigid plastic, or the same material as the push part 4 can be used.

[0027] Figure 2 This is an enlarged longitudinal section view of tube 3. Specifically, Figure 2 (a) is Figure 1 The enlarged view of part A shown below. Figure 2 (b) is Figure 1 An enlarged view of section B is shown.

[0028] Reference Figure 2 In (a), in the tube body 3, at least one flange portion 32, in this embodiment... Figure 1 The flange portion 32 on the left side is configured to protrude radially outward from the end of the tube body 31 via a bend 33. On the end face of the flange portion 32 facing outward relative to the axial direction, an annular sealing protrusion 32a is provided to seal against the connecting member 21.

[0029] In the bend 33, a first curved surface 33a is provided on the outer side of the tube body 3, i.e., the outer side of the flow path, and a second curved surface 33b is provided on the inner side of the tube body 3, i.e., the inner side of the flow path. Figure 2 In the longitudinal section shown, i.e., the section passing through the central axis of the tube 3, the radius of curvature R1 of the first curved surface 33a is smaller than the radius of curvature R2 of the second curved surface 33b. When the first curved surface 33a and the second curved surface 33b are composed of multiple curved surfaces with multiple radii of curvature, the largest radius of curvature can be compared. That is, the largest radius of curvature of the first curved surface 33a can also be made smaller than the largest radius of curvature of the second curved surface 33b.

[0030] Near the bend 33, the thickness t1 of the tube body 31 may be greater than the thickness t2 of the flange 32. In this case, the radial thickness t of the bend 33 decreases continuously from the tube body 31 side toward the flange 32 side. Therefore, the radial thickness t of the bend 33 is smaller than the thickness t1 of the tube body 31 and larger than the thickness t2 of the flange 32. Here, the radial thickness t of the bend 33 is defined as the thickness in the direction perpendicular to the tangent at a predetermined position relative to the first curved surface 33a or the second curved surface 33b.

[0031] Reference Figure 2 In section (b), the flange portion 32 is configured to protrude radially outward from the end of the tube body 31 via a corner portion 34. In the corner portion 34, the outer side of the tube body 3, like the curved portion 33, is provided with a curved surface 34a having a radius of curvature R1, corresponding to the first curved surface portion 33a. On the other hand, the inner side of the tube body 3 does not have a curved surface corresponding to the second curved surface portion 33b. Strictly speaking, there is a portion with a small radius of curvature on the inner side of the tube body 3, but its radius of curvature is very small compared to the radius of curvature R1 of the curved surface portion 34a. Furthermore, the maximum thickness t3 of the curved surface portion 34a in the direction perpendicular to the tangent at a predetermined position is very large compared to the thickness t1 of the tube body 31 and the thickness t2 of the flange portion 32.

[0032] If Figure 2 The curved portion 33 shown in (a) and Figure 2Comparing the corner portion 34 shown in (b), it can be seen from the shape and structure that since the curved portion 33 has lower rigidity than the corner portion 34, the flange portion 32 is more likely to bend, for example, in the axial direction, using the curved portion 33 as a fulcrum. Therefore, the end of the tube body 3 with the curved portion 33 is more prone to elastic deformation than the end of the tube body 3 with the corner portion 34. Furthermore, by making the thickness t2 of the flange portion 32 smaller than the thickness t1 of the tube body 31 as described above, the flange portion 32 can be made more prone to elastic deformation.

[0033] In the case where the retaining member 20 is integrally formed as in the clamp valve 1 of this embodiment, in order to accommodate the tube body 3 into the retaining member 20, it is necessary to elastically deform one end of the tube body 3 while inserting it into the retaining member 20. Therefore, during assembly, by compressing the end of the tube body 3 provided with the bend 33 radially inward to deform it, the tube body 3 can be easily inserted into the retaining member 20. As a result, the tube body 3 with the flange 32 can be easily installed relative to the retaining member 20. Furthermore, since the bend 33 is provided with a first curved surface 33a and a second curved surface 33b, stress is dispersed during elastic deformation, preventing damage to the bend 33 and the vicinity of the bend 33 caused by stress concentration.

[0034] Furthermore, due to the high rigidity of the corner portion 34, it is difficult to use the corner portion 34 as a fulcrum to flex the flange portion 32, for example, in the axial direction. Consequently, the end of the tube body 3 with the corner portion 34 is difficult to elastically deform. Therefore, it is difficult to insert the tube body 3 into the retaining member 20 while elastically deforming the end of the tube body 3 with the corner portion 34. Even if deformation is forced, the tube body may be damaged, resulting in compromised sealing.

[0035] Therefore, since assembly can be performed by inserting either end of the tube body 3 into the retaining member 20, it is also possible to configure the tube body 3 to have bends 33 on both sides of the flange 32. This allows for quick and reliable assembly without requiring end confirmation during assembly. Furthermore, by providing the bend 33 only at one end of the tube body 3 as described above, compared to providing the bend 33 at both ends of the tube body 3, the metal mold used to manufacture the tube body 3 can be made cheaper. That is, the core on the flow path side of the tube body 3 is composed of two core halves divided at the center of the flow path by a plane orthogonal to the central axis. In this case, since the surface of the second curved surface 33b, the surface of the tube body 31, and the surface of the flange 32 are continuous surfaces, although there is no functional problem, the insertion parting line would be noticeable. To improve its appearance, the core half on the side with the bend 33 is integrally manufactured using a larger metal mold material. On the other hand, since corner 34 is a roughly right angle, it will not be conspicuous if a nesting line is provided to match its front end. Therefore, the core half without the bend 33 can be manufactured separately so that the nesting line is positioned at the portion corresponding to corner 34. Thus, the core half without the bend 33 can be manufactured more cost-effectively than the core half with the bend 33. The structure of the tube body 3 with the bend 33 provided for the flange 32 as described above can also be applied to valves other than pinch valves that have the same structure, such as butterfly valves.

[0036] Figure 3 This is a three-dimensional view of tube 3. Figure 4 This is a perspective view showing the assembly of the tube body 3 and the pressing part 4. The tube body 3 also has a connecting part 35, which is provided on the outer surface of the tube body 3, that is, on the outer surface of the tube body 31, and connects the rod member 6 to the tube body 3 in a transverse arrangement. In other words, the connecting part 35 is provided with a through hole 36 that allows the rod member 6 to be inserted and extends laterally relative to the tube body 3. The connecting part 35 is integrally formed into a cylindrical shape, but it can be arbitrarily formed as long as the through hole 36 is provided. The connecting part 35 is integrally provided with respect to the tube body 31.

[0037] In order to assemble the tube body 3 and the pusher part 4 in the valve part 2, the tube body 3 is elastically deformed and housed in the retaining member 20 as described above. Next, the rod member 6 is inserted into the through hole 36 of the connecting part 35. Then, by installing the rod member 6 to the front end of the pusher part 4, the assembly of the tube body 3 and the pusher part 4 is completed.

[0038] Figure 5This is a cross-sectional view of the tube body 3. The inner surface of the through hole 36 of the connecting portion 35 is formed into a generally cylindrical shape corresponding to the cylindrical rod member 6. In the inner surface of the through hole 36, a flat surface 37 spanning the entire length of the through hole 36 is provided on the surface on the side of the tube body 31. By providing the flat surface 37, the step difference between the entrance portion 36a of the through hole 36 and the outer surface of the tube body 31 can be eliminated. As a result, the rod member 6 can be smoothly inserted into the through hole 36 during assembly.

[0039] Figure 6 This is a front view of the pressing part 4. Figure 7 This is a cross-sectional view of the pressing part 4. At the front end of the pressing part 4, a locking recess 41 is provided, capable of engaging the rod member 6 in a snap-fit ​​manner. The locking recess 41 is composed of a first recess 42 and a second recess 43. The first recess 42 is complementaryly formed to receive the connecting part 35, and the second recess 43 extends along the same line, sandwiching the first recess 42, and is complementaryly formed to receive the rod member 6. Only at both ends of the second recess 43 are a pair of engaging claws 44 capable of engaging with the rod member 6.

[0040] A pair of engaging claws 44 are arranged opposite each other along the edge of the second recess 43. The gap between the pair of engaging claws 44 is smaller than the diameter of the cylindrical rod member 6. On the other hand, in the second recess 43, the gap between the edges of the portions where the engaging claws 44 are not provided is larger than the diameter of the cylindrical rod member 6. During assembly, if the pressing part 4 is pushed in relative to the cylindrical rod member 6, the rod member 6 elastically deforms the pair of engaging claws 44 in the second recess 43 to separate the pair of engaging claws 44, allowing the rod member 6 to be snapped into place. As a result, the pressing part 4, the rod member 6, and the tube body 3 connected to the rod member 6 can be simply and firmly connected as a single unit.

[0041] Figure 8 This is a longitudinal cross-sectional view showing the opening and closing of the flow path in tube 3. Figure 8 In the middle (a), it indicates that the pinch valve 1 is fully open. Figure 8 (b) indicates the fully closed state of pinch valve 1. Figure 8 In this version, the components of the pinch valve 1 other than the tube body 3, the pushing part 4, and the rod component 6 are omitted. The pinch valve 1 is configured such that by pushing or releasing the pushing part 4 of the rod component 6, the tube body 3 is deformed, thereby opening or closing the flow path.

[0042] Since the pressing part 4 is connected to the tube body 3 via the rod member 6, when the pressing part 4 presses the tube body 3, the entire length of the rod member 6 presses the tube body 3. At this time, no load is applied to the connecting part 35. On the other hand, when the pressing of the tube body 3 by the pressing part 4 is released, for example, if the piston 11 is raised, the pressing part 4 rises, and the rod member 6, which is engaged with the pressing part 4, pulls the tube body 31 upward via the connecting part 35. As a result, the clamp valve 1 can be reliably made fully open. In other words, by properly designing the shape, arrangement, and size of the locking claw 44, a locking force sufficient to prevent the rod member 6 from disengaging can be obtained when the tube body 31 is pulled upward in order to make the clamp valve 1 fully open. When designing the locking claw 44, the operating conditions of the clamp valve 1, the fluid pressure, and the material of the tube body 3 can also be considered.

[0043] Therefore, even if the elastic material such as rubber constituting the tube body 3 deteriorates due to aging, resulting in a decrease in the elastic recovery force of the tube body 3, plastic deformation of the tube body 3, and the fixation of the inner surfaces of the tube body 3 when fully closed, the opening and closing of the pinch valve 1 can still be reliably and accurately controlled. Furthermore, the connecting part 35 is not subjected to load when the tube body 3 is pushed by the pushing part 4; it is only subjected to load in the tensile direction when the pushing is released, pulling the tube body 31 upwards. Therefore, deterioration or damage to the connecting part 35 can be minimized. Moreover, compared to the pinch valve described in Patent Document 1, the pinch valve 1 has a structure with the addition of the rod member 6 and the connecting part 35, but as a pinch valve, it can achieve reliable opening and closing with almost no change in overall size.

[0044] The rod component 6 is preferably made to have a length approximately the same as the width of the deformed tube body 3 in the fully closed state. If the rod component 6 becomes shorter than the width of the deformed tube body 3 in the fully closed state, the edges at both ends of the rod component 6 may come into contact with the surface of the tube body 31 and damage the tube body 3. On the other hand, if the rod component 6 is longer than the width of the deformed tube body 3 in the fully closed state, it may interfere with the inner surface of the retaining component 20 or other components. Furthermore, from the viewpoint of preventing damage to the tube body 3 by the rod component 6 in the event of contact with the tube body 31, it is preferable to chamfer the edges at the ends of the rod component 6.

[0045] The structure having a connecting portion 35 that connects the rod member 6 to the tube body 3 in a transverse arrangement is applicable not only to the integrally formed retaining member 20, but also to clamp valves having a retaining member consisting of, for example, two separate halves. The rod member 6 may also be polygonal rather than cylindrical. Besides fitting, the rod member 6 can also be installed to the front end of the pusher portion 4 by fastening or other means.

[0046] Label Explanation

[0047] 1. Pinch valve; 2. Valve section; 3. Pipe body; 4. Pushing section; 5. Drive section; 6. Rod component; 10. Cylinder; 11. Piston; 12. Base plate; 13. Display section; 14. Cap; 15. O-ring; 20. Retaining component; 21. Connecting component; 22. Cap nut; 31. Pipe body; 32. Flange; 33. Bending section; 33a. First curved section; 33b. Second curved section; 34. Corner; 35. Connecting section; 36. Through hole; 41. Fitting recess; 42. First recess; 43. Second recess; 44. Engaging claw.

Claims

1. A pinch valve, characterized in that, have: The tube body is made of an elastic material and has flow paths formed inside it; Pushing section; One rod component is mounted on the front end of the aforementioned pressing part; and A connecting portion is provided on the outer surface of the tube body and has a through hole extending laterally relative to the tube body, so as to connect the rod member to the tube body in a laterally arranged manner. By pushing or releasing the tube body through the pushing part of the aforementioned rod component, the tube body is deformed, thereby opening or closing the flow path. There is no step difference between the entrance of the through hole and the outer surface of the tube.

2. The pinch valve as described in claim 1, characterized in that, The aforementioned rod component is a cylindrical component, and a fitting recess is provided at the front end of the aforementioned pressing part to fit the aforementioned rod component in a snap-fit ​​manner.

3. The pinch valve as described in claim 2, characterized in that, The aforementioned fitting recess is provided with a locking claw that can engage with the aforementioned rod component.

4. The pinch valve as described in claim 1, characterized in that, The aforementioned rod component is formed to have the same length as the width of the aforementioned tube body after deformation when the clamp valve is fully closed.

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