Wear Valve

Abstract

To suppress wear caused by friction against a body of a wear valve associated with an abutting / separating operation of a diaphragm valve element.SOLUTION: A diaphragm valve element 4 includes a fixed part 43 provided on the outer periphery of a thin film part 42 and connected to a thin film part 42. A wear valve 1 includes fixing parts 231, 36 for holding the fixed part 43 from both sides in an abutting and separating direction to fix the diaphragm valve element 4. To the surface of the fixing part 36, a diamond-like carbon coating 37 is applied for suppressing the wear of the diaphragm valve element 4 caused by friction between the fixing part 36 and the diaphragm valve element 4 associated with the abutting / separating operation of the diaphragm valve element 4.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a wear valve which comprises a flow path, a dam provided in the flow path, and a diaphragm valve body having a thin film portion, in which the thin film portion elastically deforms to cause the diaphragm valve body to move toward and away from the dam, thereby controlling the flow of fluid through the flow path. [Background technology]

[0002] In beverage filling devices, a ware valve is often used to control the amount of beverage filled into a beverage container. As shown in Patent Document 1, for example, a ware valve is equipped with a flow path, a weir provided in the flow path, and a diaphragm valve body having a thin film portion, and the thin film portion elastically deforms to cause the diaphragm valve body to come into contact with and separate from the weir, thereby controlling the fluid flowing through the flow path.

[0003] The wear valve shown in Patent Document 1 is of the manually opened and closed type, but in beverage filling devices, for example, an air-operated wear valve 5 as shown in Figs. 3, 5 and 7 is used.

[0004] The wear valve 5 is composed of a drive portion 2, a body 6, and a diaphragm valve element 4 that is fixedly sandwiched between the drive portion 2 and the body 6.

[0005] The actuator 2 has a piston 25 and a spring 28 inside. The piston 25 rises or falls in a piston chamber 27 due to the operating air introduced into the actuator 2 or the elastic force of the spring, and the center of the diaphragm valve element 4 rises or falls with the rise or fall of the piston 25. This causes the diaphragm valve element 4 to separate from or come into contact with the weir 35, and the valve opening or closing operation of the weir valve 5 is performed.

[0006] In the body 6, a flow path is formed from an input port 33 to an output port 34 by an input side flow path 31 and an output side flow path 32. A weir 35 against which the diaphragm valve body 4 comes into contact and separates is provided on the flow path.

[0007] The diaphragm valve body 4 has a two-layer structure consisting of a first layer 4a made of polytetrafluoroethylene (PTFE) on the liquid-contacting surface side and a second layer 4b made of ethylene-propylene-diene rubber (EPDM) on the opposite side to the liquid-contacting surface side. The diaphragm valve body 4 has a thin film portion 42, and a fixed portion 43 connected to the thin film portion 42 is provided on the outer periphery of the thin film portion 42. The fixed portion 43 is sandwiched by the fixing portion 231 of the driving portion 2 and the fixing portion 36 of the body 6 from both directions in which the diaphragm valve body 4 abuts against and separates from the weir 35 (up and down directions in the figure), thereby fixing the diaphragm valve body 4 to the wear valve 5. The fixing portion 36 has a convex portion 36a, and the convex portion 36a compresses the diaphragm valve body 4, thereby making the external seal of the diaphragm valve body 4 stronger.

[0008] The reason why these types of ware valves are often used in beverage filling equipment is that, compared to poppet valves, the flow path structure is relatively simple and there is little liquid accumulation. From the viewpoint of food hygiene, valves used in beverage filling equipment are frequently cleaned. Therefore, ware valves with a simple flow path structure are suitable. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2018-62953 A Summary of the Invention [Problem to be solved by the invention]

[0010] However, in the above-mentioned conventional technology, when the wear valve is repeatedly opened and closed (i.e., the movement of the diaphragm valve body 4 toward and away from the weir 35), the thin film portion 42 of the diaphragm valve body 4 rubs against the end portion (convex portion 36a) of the fixed portion 36 of the body 6, causing wear of the first layer 4a and the risk of wear powder being generated.

[0011] The mechanism by which this wear occurs is as follows. As shown in Fig. 3, when the piston 25 is at the lower limit position and the diaphragm valve body 4 is in a state of abutting against the weir 35 (i.e., the wear valve 5 is in a valve-closed state), no load is applied to the thin film portion 42 of the diaphragm valve body 4. When the valve is opened from this state, first, as shown in Fig. 7, the piston 25 starts to move upward from the lower limit position, and the diaphragm valve body 4 is elastically deformed in a direction away from the weir 35. When the diaphragm valve body 4 is elastically deformed in this way, the fixed portion 43 of the diaphragm valve body 4 is in a state of being clamped and fixed from above and below in the figure, so that the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve body 4, which was not loaded in Fig. 3, is compressed or pushed outward (in the direction of the arrow Y12) of the diaphragm valve body 4, as shown in Fig. 8.

[0012] Then, when the piston 25 is further moved upward and reaches the upper limit position, the wear valve 5 is in a fully open state as shown in Fig. 5. In this fully open state, the fixed portion 43 of the diaphragm valve element 4 is sandwiched from above and below in the figure, and the center of the diaphragm valve element 4 is pulled upward, so that the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve element 4, which was compressed or pressed in in Fig. 8, is stretched in the direction toward the center of the diaphragm valve element 4 (the direction of the arrow Y11) as shown in Fig. 6.

[0013] Then, when the valve is closed from the fully open state, the piston 25 starts to move downward from the upper limit position, and the diaphragm valve element 4 is elastically deformed in the direction of contacting the weir 35, so that the diaphragm valve element 4 returns to the state shown in Fig. 7. In other words, the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve element 4, which was stretched in Fig. 6, is again compressed or pushed outward of the diaphragm valve element 4 (in the direction of the arrow Y12).

[0014] Then, as shown in FIG. 3, when the piston 25 moves to the lower limit position, the diaphragm valve body 4 abuts against the weir 35, and the wear valve 5 is closed, the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve body 4, which was in a compressed or pushed-in state in FIG. 7, is stretched in the direction of arrow Y13, as shown in FIG. 4, and the thin film portion 42 returns to a state where it is not under load.

[0015] As described above, when the diaphragm valve body 4 moves in contact with and away from the body, the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve body 4 is stretched in the directions of the arrows Y11 and 13, and compressed or pushed in the direction of the arrow Y12, causing friction between the diaphragm valve body 4 and the end (projection portion 36a) of the fixed portion 36 of the body 6. This friction causes wear of the first layer 4a of the diaphragm valve body 4, generating wear powder.

[0016] In a wear valve used in a beverage filling device, when the first layer 4a of the diaphragm valve body 4 is worn, the wear powder may be mixed into the beverage. Under the Food Sanitation Act, the PTFE forming the first layer 4a is a material that is harmless to the human body when ingested, but the wear powder large enough to be visible in the beverage is problematic in appearance. For this reason, a wear valve 5 with wear in the first layer 4a may generate large wear powder as the wear progresses, so it must be replaced before the wear powder large enough to be visible is generated, even if there is no problem with the function of the wear valve 5 itself. Even if there is no problem with the function of the wear valve 5 itself, it is not economical to have to replace it, and a wear valve that suppresses the wear of the diaphragm valve body and the generation of wear powder as much as possible is desired.

[0017] The present invention has been made to solve the above problems, and has an object to provide a wear valve that is capable of suppressing the generation of wear powder caused by friction between the diaphragm valve body and the wear valve body as the diaphragm valve body moves toward and away from the wear valve body. [Means for solving the problem]

[0018] In order to solve the above problems, the wear valve of the present invention has the following configuration. (1) A wear valve comprising a flow path, a weir provided in the flow path, and a diaphragm valve element having a thin film portion, the thin film portion elastically deforming to cause the diaphragm valve element to move toward and away from the weir, thereby controlling a fluid flowing through the flow path, the diaphragm valve element having a fixed portion connected to the thin film portion on an outer periphery of the thin film portion, the wear valve having a fixing portion that fixes the diaphragm valve element by clamping the fixed portion from both directions of the contact and separation, and a coating of diamond-like carbon is applied to a surface of the fixing portion to suppress wear of the diaphragm valve element caused by friction between the fixing portion and the diaphragm valve element accompanying the contact and separation movement of the diaphragm valve element, the coating is applied to a portion of the fixing portion that comes into contact with a surface of the diaphragm valve body on a side of a liquid-contacting surface that comes into contact with the fluid; It is characterized by:

[0019] (2) In the wear valve described in (1), the wear valve is an air-operated wear valve used in a beverage filling device.

[0021] (4) The wear valve according to any one of (1) to (3), characterized in that the coefficient of dynamic friction of the surface of the coating is 0.1 or more and 0.2 or less.

[0022] (5) In the wear valve described in any one of (1) to (4), the diaphragm valve body is composed of two layers, a first layer on the side that contacts the fluid and a second layer on the opposite side to the side that contacts the fluid, the first layer is made of a fluororesin, and the second layer is made of ethylene propylene diene rubber. Effect of the Invention

[0023] In the wear valve of the present invention, the surface of the fixing part that fixes the diaphragm valve body is coated with diamond-like carbon, so that the dynamic friction coefficient of the surface of the fixing part is reduced. If the dynamic friction coefficient of the surface of the fixing part is reduced, it is possible to suppress the occurrence of wear on the diaphragm valve body even if friction occurs between the diaphragm valve body and the fixing part.

[0024] When a wear valve is used in a beverage filling device, if wear occurs on the diaphragm valve body and visible wear powder gets mixed into the fluid, the wear valve has to be replaced even if there is no problem with the function of the wear valve itself. However, if wear on the diaphragm valve body can be suppressed, it is possible to extend the life of the wear valve before it needs to be replaced. [Brief description of the drawings]

[0025] [Figure 1] FIG. 2 is a cross-sectional view of the wear valve according to the embodiment. [Diagram 2] FIG. 2 is a partially enlarged view of the X11 portion of FIG. [Diagram 3] FIG. 1 is a cross-sectional view of a prior art wear valve in a closed state. [Figure 4] FIG. 4 is a partially enlarged view of a portion X12 in FIG. [Diagram 5] FIG. 1 is a cross-sectional view of a prior art wear valve in an open state. [Figure 6] FIG. 6 is a partial enlarged view of a portion X13 in FIG. 5. [Figure 7] FIG. 1 is a cross-sectional view of a wear valve according to the prior art, showing the valve closing state. [Figure 8] FIG. 8 is a partially enlarged view of a portion X14 in FIG. [Figure 9] This shows the state of the diaphragm valve body observed from the first layer side after the diaphragm valve body was subjected to contact and separation operations 1.5 million times when no coating was applied to the fixing portion. [Figure 10]This shows the state of the diaphragm valve body observed from the first layer side after the diaphragm valve body was subjected to 1.5 million consecutive contact and separation operations in a case where a coating with a dynamic friction coefficient of 0.15 to 0.2 was applied to the fixed portion. [Figure 11] This shows the state of the diaphragm valve element observed from the first layer side after the diaphragm valve element was subjected to 1.5 million consecutive contact and separation operations in a case where a coating with a dynamic friction coefficient of 0.1 to 0.15 was applied to the fixed portion. [Figure 12] 13 is a table summarizing the results of measuring the maximum radial width of wear marks that occurred when contact and separation operations were performed 500,000 times, 1,000,000 times, and 1,500,000 times. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the wear valve of the present invention will be described in detail with reference to the drawings.

[0027] (About the composition of the wear valve) First, the configuration of the wear valve 1 according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a cross-sectional view of the wear valve 1 according to this embodiment. Figure 2 is a partially enlarged view of the X11 portion of Figure 1.

[0028] The wear valve 1 is a normally closed type air operated on-off valve used in beverage filling equipment, and is composed of a drive unit 2, a body 3, and a diaphragm valve element 4 that is clamped and fixed between the drive unit 2 and the body 3.

[0029] The drive unit 2 is composed of an upper cover 21, a lower cover 22, a rod cover 23, a piston rod 24, a piston 25, and a compressor 26.

[0030] The upper cover 21 is made of, for example, aluminum die casting, and is formed in a cup shape with one end (the upper end in FIG. 1) closed and the other end open. The lower cover 22 is connected to the end portion on the open side of the upper cover 21.

[0031] The lower cover 22 is made of, for example, aluminum die casting, and together with the upper cover 21 forms a piston chamber 27 .

[0032] 1, and the piston chamber 27 is divided into an upper piston chamber 271 and a lower piston chamber 272 by this piston 25. A spring 28 is disposed in the upper piston chamber 271 so as to be compressed by the upper wall surface of the upper piston chamber 271 and the upper end surface of the piston 25, and the spring 28 constantly biases the piston 25 towards the lower cover 22.

[0033] Moreover, the upper piston chamber 271 communicates with the first operation port 211 through a through hole 213 provided in the side surface of the upper cover 21. Furthermore, the lower piston chamber 272 communicates with the second operation port 212 through a through hole 214 provided in the side surface of the upper cover 21.

[0034] A piston rod 24 inserted through a piston chamber 27 is coaxially connected to the piston 25. The piston rod 24 is made of, for example, stainless steel and formed into a cylindrical shape with a longitudinal direction parallel to the direction in which the piston 25 ascends or descends, and protrudes downward in Fig. 1 from the piston chamber 27 through a guide hole 221 provided in the lower cover 22. The part of the piston rod 24 protruding from the piston chamber 27 is protected by a cylindrical rod cover 23 connected to the side of the lower cover 22 opposite to the upper cover 21 side.

[0035] The rod cover 23 is made of, for example, aluminum die casting. The end portion (the lower end portion in FIG. 1) of the rod cover 23 on the side opposite to the lower cover 22 side is formed in a flange shape, and serves as a fixing portion 231 for fixing the diaphragm valve body 4.

[0036] The diaphragm valve 4 is composed of two layers: a first layer 4a made of polytetrafluoroethylene (PTFE) and a second layer 4b made of ethylene-propylene-diene rubber (EPDM). The surface of the first layer 4a becomes the surface that comes into contact with the beverage, which is the fluid flowing through the flow path provided in the body 3 (hereinafter, the liquid-contact surface).

[0037] A connecting portion 44 is provided in the center of the surface of the diaphragm valve element 4 opposite the liquid-contacting surface, and the connecting portion 44 is connected to the piston rod 24 via the compressor 26. A contact portion 41 that contacts and separates from the weir 35 of the body 3 is provided in the center of the liquid-contacting surface side of the diaphragm valve element 4. A thin film portion 42 is provided on the outer periphery of the contact portion 41, and a fixed portion 43 is provided on the outer periphery of the thin film portion 42. Positioning members 45, 46 are provided in the upper and lower end faces of the fixed portion 43, respectively.

[0038] The body 3 is made of stainless steel such as SUS316L, and a flow path from an input port 33 to an output port 34 is formed by an input side flow path 31 and an output side flow path 32. A weir 35, against which the diaphragm valve element 4 comes into contact and separates, is provided on the flow path so as to protrude toward the diaphragm valve element 4 side.

[0039] The portion of the body 3 that faces the fixed portion 231 of the rod cover 23 with the diaphragm valve element 4 in between is the fixed portion 36. The fixed portion 231 and the fixed portion 36 clamp the fixed portion 43 of the diaphragm valve element 4 from both directions in which the diaphragm valve element 4 abuts against and separates from the weir 35 (the up and down directions in Figs. 1 and 2), thereby fixing the diaphragm valve element 4. The fixed portion 36 has an annular protrusion 36a that is coaxial with the piston 25 and the piston rod 24 and has a radial direction perpendicular to the abutment and separation direction, and this protrusion 36a compresses the diaphragm valve element 4, thereby making the external seal of the diaphragm valve element 4 stronger.

[0040] A diamond-like carbon coating 37 (e.g., hydrogen-containing amorphous carbon (aC:H)) is applied to the surface of the fixed portion 36 of the body 3. This coating 37 is formed, for example, by chemical vapor deposition (CVD deposition) and has a thickness of 1 to 20 μm. The dynamic friction coefficient of the surface of this coating 37 is preferably in the range of 0.1 to 0.2, more preferably in the range of 0.1 to 0.15. This dynamic friction coefficient is a value obtained by conducting a ball-on-disk type friction test using a disk-shaped test piece having the same coating as the coating 37 on its surface and a ball made of carbon-chromium bearing steel (SUJ2).

[0041] (About the operation of the wear valve) First, we will explain the valve opening operation of the wear valve 1. When operating air is supplied from the second operating port 212 to the lower piston chamber 272 through the through hole 214, the pressure in the lower piston chamber 272 increases, and the piston 25 rises toward the upper piston chamber 271. At this time, the air in the upper piston chamber 271 is exhausted from the first operating port 211.

[0042] Since the piston rod 24 which penetrates the piston chamber 27 is connected to the piston 25, when the piston 25 rises in the piston chamber 27, the piston rod 24 also rises accordingly.

[0043] Furthermore, since the diaphragm valve element 4 is connected to the piston rod 24 via the compressor 26 by the connecting portion 44, when the piston rod 24 rises, the thin film portion 42 elastically deforms accordingly, and the central portion of the diaphragm valve element 4 rises. As the central portion of the diaphragm valve element 4 rises, the abutment portion 41 separates from the weir 35, and the wear valve 1 enters the valve open state.

[0044] Next, the valve closing operation will be described. When the supply of operating air to the lower piston chamber 272 is stopped while the wear valve 1 is in the open state, the piston 25 descends toward the lower piston chamber 272 due to the biasing force of the spring 28. When the piston 25 descends within the piston chamber 27, the piston rod 24 connected to the piston 25 also descends.

[0045] Furthermore, when the piston rod 24 descends, the thin film portion 42 elastically deforms accordingly, and the central portion of the diaphragm valve element 4 descends. As the central portion of the diaphragm valve element 4 descends, the abutment portion 41 abuts against the weir 35, and the wear valve 1 enters the valve open state.

[0046] When the above-mentioned contact and separation action of the diaphragm valve body 4 against the weir 35 is repeated, friction may occur between the thin film portion 42 of the diaphragm valve body 4 and the end (convex portion 36a) of the fixed portion 36 of the body 6. How friction occurs between the diaphragm valve body 4 and the end (convex portion 36a) of the fixed portion 36 of the body 6 will be explained using Figures 3 to 8. Note that Figures 3 to 8 show a wear valve 5 according to the prior art, but since the configuration used in the explanation is common, the following explanation will be given as that of the wear valve 1 according to this embodiment.

[0047] As shown in Fig. 3, when the piston 25 is at the lower limit position and the diaphragm valve element 4 is in contact with the weir 35 (i.e., the wear valve 1 is in a closed state), no load is applied to the thin film portion 42. When the valve is opened from this state, first, as shown in Fig. 7, the piston 25 starts to move upward from the lower limit position, and the diaphragm valve element 4 is elastically deformed in a direction away from the weir 35. When the diaphragm valve element 4 is elastically deformed in this way, the fixed portion 43 of the diaphragm valve element 4 is in a state of being clamped and fixed from above and below in the figure, so that the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve element 4, which was not loaded in Fig. 3, is compressed or pushed outward of the diaphragm valve element 4 (in the direction of the arrow Y12) as shown in Fig. 8.

[0048] Then, when the piston 25 is further moved upward and reaches the upper limit position, the wear valve 1 is in a fully open state as shown in Fig. 5. In this fully open state, the fixed portion 43 of the diaphragm valve element 4 is sandwiched from above and below in the figure, and the center of the diaphragm valve element 4 is pulled upward, so that the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve element 4, which was compressed or pressed in in Fig. 8, is stretched toward the center of the diaphragm valve element 4 (in the direction of the arrow Y11) as shown in Fig. 6.

[0049] Then, when the valve is closed from the fully open state, the piston 25 starts to move downward from the upper limit position, and the diaphragm valve element 4 is elastically deformed in the direction of contacting the weir 35, so that the diaphragm valve element 4 returns to the state shown in Fig. 7. In other words, the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve element 4, which was stretched in Fig. 6, is again compressed or pushed outward of the diaphragm valve element 4 (in the direction of the arrow Y12).

[0050] Then, when the piston 25 moves to the lower limit position, the diaphragm valve body 4 abuts against the weir 35, and the wear valve 5 is closed, the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve body 4, which was in a compressed or pushed-in state in Figure 7, is stretched in the direction of arrow Y13, as shown in Figure 4, and the thin film portion 42 returns to a state where it is not under load.

[0051] When the diaphragm valve body 4 moves in and out of contact, as described above, the vicinity of the boundary between the thin film portion 42 and the fixed portion 43 of the diaphragm valve body 4 is stretched in the directions of arrows Y11 and 13, and compressed or pushed in the direction of arrow Y12, causing friction between the diaphragm valve body 4 and the end (convex portion 36a) of the fixed portion 36 of the body 6.

[0052] However, since the fixed portion 36 of the wear valve 1 is coated with a diamond-like carbon coating 37 as shown in FIG. 2, even if friction occurs between the diaphragm valve body 4 and the end (convex portion 36a) of the fixed portion 36 of the body 6, wear on the diaphragm valve body 4 (first layer 4a) can be suppressed.

[0053] (About the experimental results) Below, we will explain the results of an experiment in which the diaphragm valve body 4 was subjected to contact and separation operations 500,000 times, 1 million times, and 1.5 million times in the cases where no coating 37 was applied to the fixed portion 36 (convex portion 36a), where a coating 37 with a kinetic friction coefficient of 0.15 to 0.2 was applied, and where a coating 37 with a kinetic friction coefficient of 0.1 to 0.15 was applied, and the size of wear marks generated on the diaphragm valve body 4 was compared.

[0054] FIG. 9 is a diagram showing the state of the diaphragm valve body 4 observed from the first layer 4a side after the diaphragm valve body 4 has been subjected to 1.5 million contact and separation operations in a case where the coating 37 is not applied to the fixing portion 36 (convex portion 36a) (i.e., a wear valve 5 relating to the prior art).

[0055] When the diaphragm valve body 4 is subjected to 1.5 million successive contact and separation operations without applying the coating 37 to the fixed portion 36 (protrusion 36a), it is found that an arc-shaped wear mark S11 is generated on the thin film portion 42, as shown in Fig. 9. The wear mark S11 is arc-shaped because the protrusion 36a is provided in an annular shape, and friction occurs between the protrusion 36a and the thin film portion 42. The radial width of the wear mark S11 is approximately 400 µm at maximum (see Fig. 12).

[0056] Furthermore, when the contact and separation operations were performed 500,000 times and 1,000,000 times, the radial width of the wear mark S11 was a maximum of 190 μm after 500,000 times and 270 μm after 1,000,000 times, as shown in FIG.

[0057] FIG. 10 is a diagram showing the state of the diaphragm valve body 4 observed from the first layer 4a side after the diaphragm valve body 4 has been subjected to 1.5 million consecutive contact and separation operations when a coating 37 having a dynamic friction coefficient of 0.15 to 0.2 is applied to the fixed portion 36 (convex portion 36a).

[0058] When the fixed portion 36 (protruding portion 36a) is coated with a coating 37 having a dynamic friction coefficient of 0.15 to 0.2 and the contact and separation operation is performed 1.5 million times in succession, an arc-shaped wear mark S12 appears on the thin film portion 42, as shown in Fig. 10. However, it can be seen that the range in which the wear mark S12 appears is smaller than the range in which the wear mark S11 shown in Fig. 9 appears. Furthermore, the radial width of the wear mark S12 is a maximum of about 200 µm (see Fig. 12), which is about half of the wear mark S11 when the coating 37 is not applied.

[0059] Furthermore, when the contact and separation operations were performed 500,000 times and 1,000,000 times, the radial width of the wear mark S12 was a maximum of 100 μm after 500,000 times and 145 μm after 1,000,000 times, as shown in FIG.

[0060] FIG. 11 is a diagram showing the state of the diaphragm valve body 4 observed from the first layer 4a side after the diaphragm valve body 4 has been subjected to 1.5 million consecutive contact and separation operations when a coating 37 having a dynamic friction coefficient of 0.1 to 0.15 is applied to the fixing portion 36 (convex portion 36a).

[0061] When the fixed portion 36 (protruding portion 36a) is coated with a coating 37 having a dynamic friction coefficient of 0.1 to 0.15 and the contact and separation operation is performed 1.5 million times in succession, wear marks S13 are generated on the thin film portion 42 as shown in Fig. 11. However, it can be seen that the range where the wear marks S13 are generated is smaller than the range where the wear marks S11 shown in Fig. 9 are generated, and is even smaller than the range where the wear marks S12 shown in Fig. 10 are generated. Furthermore, the radial width of the wear marks S13 is a maximum of about 150 µm (see Fig. 12), which is about one third of the wear marks S11 when the coating 37 is not applied.

[0062] Furthermore, when the contact and separation operations were performed 500,000 times and 1,000,000 times, the radial width of the wear mark S13 was a maximum of 90 μm after 500,000 times and 100 μm after 1,000,000 times, as shown in FIG.

[0063] As described above, the wear valve 1 of this embodiment has the following features: (1) A ware valve 1 which includes a flow path (e.g., an input side flow path 31 and an output side flow path 32), a weir 35 provided in the flow path, and a diaphragm valve element 4 having a thin film portion 42, and which performs flow control of a fluid (e.g., a beverage) flowing through the flow path by elastically deforming the thin film portion 42, the diaphragm valve element 4 having a fixed portion 43 connected to the thin film portion 42 on the outer periphery of the thin film portion 42, the ware valve 1 having fixing portions 231, 36 which fix the diaphragm valve element 4 by clamping the fixed portion 43 from both directions of contact and separation, and a coating 37 of diamond-like carbon applied to the surface of the fixing portion 36, which suppresses wear of the diaphragm valve element 4 caused by friction between the fixing portion 36 and the diaphragm valve element 4 as the diaphragm valve element 4 moves toward and away from the weir 35.

[0064] (2) The wear valve 1 described in (1) is characterized in that the wear valve 1 is an air-operated wear valve used in a beverage filling device.

[0065] (3) In the wear valve 1 described in (1) or (2), the coating 37 is characterized in that it is applied to the portion of the fixing portion 231, 36 that contacts the surface of the diaphragm valve body 4 that contacts the fluid (beverage) (e.g., the surface of the fixing portion 36).

[0066] (4) The wear valve (1) according to any one of (1) to (3) is characterized in that the coefficient of dynamic friction of the surface of the coating (37) is 0.1 or more and 0.2 or less.

[0067] (5) In the wear valve 1 described in any one of (1) to (4), the diaphragm valve body 4 is characterized in that it is composed of two layers, a first layer 4a on the side that contacts the fluid (beverage) and a second layer 4b on the opposite side to the side that contacts the fluid (beverage), the first layer 4a is formed of a fluororesin (e.g., PTFE), and the second layer 4b is formed of ethylene propylene diene rubber.

[0068] According to the wear valve 1 having the above-mentioned configuration, the surface of the fixing part 36 that fixes the diaphragm valve body 4 is coated with a diamond-like carbon coating 37, which reduces the dynamic friction coefficient of the surface of the fixing part 36. If the dynamic friction coefficient of the surface of the fixing part 36 is reduced, even if friction occurs between the diaphragm valve body 4 and the fixing part 36, it is possible to suppress the occurrence of wear (wear marks S11, S12, S13) on the diaphragm valve body 4.

[0069] Conventionally, when a wear valve is used in a beverage filling device, a wear valve with wear (wear marks S11, S12, S13) on the diaphragm valve body 4 is at risk of generating large wear debris as the wear progresses, and so even if there is no problem with the function of the wear valve itself, it has had to be replaced before wear debris large enough to be visible to the naked eye is generated. However, if wear on the diaphragm valve body 4 can be suppressed, as in the wear valve 1 of this embodiment, it is possible to extend the life of the wear valve 1 before it needs to be replaced.

[0070] It should be noted that this embodiment is merely an example and does not limit the present invention in any way. Therefore, the present invention can be improved and modified in various ways without departing from the spirit and scope of the present invention. For example, in this embodiment, the coating 37 is applied to the surface of the fixing portion 36, but the area to which the coating 37 is applied is not limited to this, and the coating 37 may be applied only to the surface of the protruding portion 36a of the fixing portion 36, or may be applied to the entire surface of the body 3. Moreover, the fixing portion 36 does not necessarily have to have the protruding portion 36a, and may be a flat surface. [Explanation of symbols]

[0071] 1 Wear Valve 4 Diaphragm valve body 31 Input side flow path 32 Output side flow path 35 Weir 36 Fixed part 37 Coating 42 Thin Film Section 43 Fixed part 231 Fixed part

Claims

1. A wear valve comprising a flow path, a weir provided in the flow path, and a diaphragm valve element having a thin film portion, the thin film portion elastically deforming to cause the diaphragm valve element to move toward and away from the weir, thereby controlling a fluid flowing through the flow path, the diaphragm valve body includes a fixed portion connected to the thin film portion on an outer periphery of the thin film portion; the wear valve includes a fixing portion that fixes the diaphragm valve body by clamping the fixed portion from both directions of the contact and separation; a surface of the fixing portion being coated with diamond-like carbon, thereby suppressing wear of the diaphragm valve body caused by friction between the fixing portion and the diaphragm valve body accompanying the contact and separation movement of the diaphragm valve body; the coating is applied to a portion of the fixing portion that comes into contact with a surface of the diaphragm valve body on a side of a liquid-contacting surface that comes into contact with the fluid; It is a liquid-contact surface. Wear valve featuring.

2. 2. The wear valve of claim 1, The wear valve is an air-operated wear valve used in a beverage filling device; Wear valve featuring.

3. The wear valve according to claim 1 or 2, The coefficient of dynamic friction of the surface of the coating is 0.1 or more and 0.2 or less; Wear valve featuring.

4. The wear valve according to any one of claims 1 to 3, The diaphragm valve body is The membrane is composed of two layers, a first layer on the side that comes into contact with the fluid, and a second layer on the opposite side to the side that comes into contact with the fluid. the first layer is formed of a fluororesin; the second layer is formed of ethylene propylene diene rubber; Wear valve featuring.

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