JP2012237389A - Diaphragm valve and nozzle switching valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diaphragm valve which does not cause the leakage of liquid all the time from a gap between the diaphragm valve and an opening edge of an outer pipe at a double-pipe irrespective of a time when low liquid-pressure is applied to the diaphragm valve or a time when high liquid-pressure is applied thereto in a nozzle switching valve device, and the nozzle switching valve device.SOLUTION: The nozzle switching valve device 1 comprises: a body casing 2 having a first passage 20; a rotating head 3; a valve body 9; the diaphragm valve 11 which seals a valve seat 26A being an opening edge of an inner pipe 26 of the double-pipe 2B so as to be openable and closable, and blocks the first passage 20 and a second passage 28; a pressing part 19 which elastically energizes the diaphragm valve 11 and presses it to the valve seat 26A; and a valve support member 14 which grips a part 11C to be gripped of the diaphragm valve 11 and supports it. The part 11C to be gripped is formed into a substantially-circular cross sectional shape at its cross section in the valve diameter direction.

Description

  The present invention relates to a nozzle switching valve device that includes a plurality of nozzle portions that can be switched and includes a diaphragm valve that opens and closes an internal flow path.

  Conventionally, as this type of nozzle switching valve device, for example, the one described in Patent Document 1 below is known. As shown in FIG. 6, the nozzle switching valve device 51 described in this document includes a plurality of nozzle mounting ports 61, 61,... On a pivot 52 </ b> A on one end side of a main casing 52 having a first flow path 60 therein. A rotary head 53 having a. A valve body 62 having a valve flow path 62 </ b> A is interposed between one end of the main body casing 52 and the rotary head 53. The valve body 62 communicates the nozzle flow path 61A of the rotary head 53 connected to one nozzle mounting opening 61 and the first flow path 60 of the main body casing 52 by the rotation of the rotary head 53 and other nozzle mounting openings. The nozzle flow paths 61 and 61 are switched so as to close the nozzle flow path 61 </ b> A of the rotary head 53 connected to 61. At the other end of the main casing 52, a second flow path 64 is provided between the inner pipe portion 63 in which the first flow path 60 is contained and the inner pipe portion 63 disposed outside the inner pipe portion 63. A double pipe portion 52 </ b> B composed of the outer pipe portion 65 is formed. A pipe connection part 52C connected to the external pipe communicates with the second flow path 64 of the double pipe part 52B and is provided in the main body casing 52.

  Furthermore, the valve seat 63A, which is the opening edge of the inner pipe 63, is sealed so that it can be opened and closed, and the diaphragm valve 67 that shuts off the first flow path 60 and the second flow path 64, and the diaphragm valve 67 are made elastic. A valve pressing member 68 and a spring 70 that urges and presses against the valve seat 63A, and a sandwiched portion 67C formed over the entire periphery on the periphery of the diaphragm valve 67 are connected to an opening edge 65A of the outer tube portion 65 of the double tube portion 52B. And a valve support member 69 that is sandwiched and supported in a sealed manner. The diaphragm valve 67 extends in a direction perpendicular to the flat plate valve portion 67A from the entire periphery of the outer peripheral edge of the flat plate valve portion 67A, and a flat plate valve portion 67A that opens and closes the valve seat 63A of the inner pipe portion 63. The connecting plate portion 67B is formed, and the clamped portion 67C extends outward from the connecting plate portion 67B in the direction perpendicular to the outer peripheral edge of the connecting plate portion 67B. The sandwiched portion 67C has a substantially square cross section when viewed in the diameter direction, and is sandwiched between the opening edge portion 65A of the outer tube portion 65 and the sandwiching surface 69A of the valve support member 69. It is like that.

  In the nozzle switching valve device 51, the chemical solution from the boom flows into the second flow path 64 through the pipe connection portion 52C. The chemical solution in the second flow path 64 presses the flat plate valve portion 67A of the diaphragm valve 67 and opens the opening edge 63A of the inner tube portion 63. By opening the valve seat 26A, the chemical liquid that has flowed into the first flow path 60 passes through the valve flow path 62A of the valve body 62 from the pivot portion 52A, passes through the nozzle flow path 61A of the nozzle mounting port 61, and the nozzle section. From outside.

JP 2009-22830 A

  By the way, in the above-described conventional nozzle switching valve device 51, since the cross-sectional shape of the sandwiched portion 67C of the diaphragm valve 67 is formed in a substantially square shape, the opening edge portion 65A of the outer tube portion 65 and the valve support member 69 Even if it is clamped by the clamping surface 69A, the surface contact state before and after clamping does not change. Therefore, when the cock is closed and the hydraulic pressure is low, even if there is no liquid leakage between the sandwiched portion 67C of the diaphragm valve 67 and the opening edge portion 65A of the outer pipe portion 65, the cock is opened and the hydraulic pressure is reduced. When it becomes high, liquid leakage may occur from between the diaphragm valve 67 and the outer pipe portion 65. In particular, since the diaphragm valve 67 is composed of a rubber member, the rubber elastic force is likely to gradually decrease due to deterioration over time, and it is expected that the degree of liquid leakage will gradually increase.

  The present invention has been made in view of the above-described problems of the related art, and it is always possible to use a diaphragm valve and a double pipe regardless of whether a low hydraulic pressure or a high hydraulic pressure is applied to the diaphragm valve. It is an object of the present invention to provide a diaphragm valve and a nozzle switching valve device that does not cause liquid leakage from the opening edge of the outer tube portion in the portion.

  In order to achieve the above object, a diaphragm valve according to the present invention is composed of an elastic member, a flat valve portion that opens and closes a valve seat of a flow path formed in a nozzle switching valve device, and a flat plate shape And a clamped portion that extends from the entire circumference of the valve portion and is clamped in the nozzle switching valve device, and has a substantially circular cross-sectional shape in the valve diameter direction of the clamped portion. It is.

  Further, the nozzle switching valve device according to the present invention includes a rotary head having a plurality of nozzle attachment ports rotatably provided at one end portion of the main body casing having the first flow path therein, and one end portion of the main body casing. Between the rotating head and the rotating head, the nozzle head channel connected to one nozzle mounting port and the first channel of the main body casing communicate with one nozzle mounting port by rotation of the rotating head and the rotating head connected to the other nozzle mounting port. A valve body for switching the nozzle flow path so as to close the nozzle flow path is interposed, and the other end portion of the main body casing is provided with an inner pipe portion in which the first flow path is located, and outward of the inner pipe portion. A double pipe portion is formed which is arranged and formed with an outer pipe portion including a second flow path between the inner pipe portion and a pipe connection portion connected to an external pipe is a second pipe portion of the double pipe portion. Provided in the main casing in communication with the flow path, 2. The diaphragm valve according to claim 1, wherein a valve seat which is an opening edge portion of the inner tube portion is sealed so as to be freely opened and closed, and the first flow path and the second flow path are shut off, and the diaphragm valve is elastically energized. A valve that supports the pressing portion pressed against the valve seat and the sandwiched portion formed on the entire periphery of the diaphragm valve in a liquid-sealed manner between the opening edge of the outer tube portion of the double tube portion And a support member.

  The diaphragm valve and the nozzle switching valve device according to the present invention uses the diaphragm valve having the sandwiched portion formed in a substantially circular cross-sectional shape in the valve diameter direction, so that the sandwiched portion is the outer tube portion. When sandwiched between the opening edge and the valve support member, the sandwiched portion is elastically deformed and flattened, and partly comes into surface contact. Therefore, not only when the hydraulic pressure in the second flow path is low, but also when the hydraulic pressure in the second flow path is high, the gap between the sandwiched portion of the diaphragm valve and the opening edge of the outer tube portion is always firmly secured. And can be sealed. Thereby, it is possible to reliably avoid liquid leakage from between these.

1 is an external view of a nozzle switching valve device according to an embodiment of the present invention. It is a sectional side view of the nozzle switching valve device. It is a disassembled perspective view of the nozzle switching valve device. It is a figure which shows the diaphragm valve of the said nozzle switching valve apparatus, (a) is a top view, (b) is a front sectional view, (c) is a bottom view, (d) is a side view, The inside of the circle e is (b) FIG. It is the perspective view which looked up at the said diaphragm valve from diagonally downward. It is a sectional side view of the conventional nozzle switching valve device.

Embodiments of the present invention will be described with reference to the drawings. The embodiment described below is merely an example embodying the present invention, and does not limit the technical scope of the present invention. 1 is an external view of a nozzle switching valve device according to an embodiment of the present invention, FIG. 2 is a side sectional view of the nozzle switching valve device, and FIG. 3 is an exploded perspective view of the nozzle switching valve device.
In each figure, the nozzle switching valve device 1 according to this embodiment is a main body casing 2, a rotary head 3, a packing 4, a packing 5, a slide locking pin 6, and a lid member 7, which will be described later in detail. , O-ring 8, valve body 9, O-ring 10, diaphragm valve 11, valve pressing member 12, spring 13, valve support member 14, cap 15, cap nut 16, detent piping device 17, packing 18, and O A ring 35;

  The main body casing 2 is formed in a letter T shape when seen from the side, and is bent in a direction perpendicular to the pivot portion 2A at the other end portion with a straight cylindrical pivot portion 2A formed at one end portion thereof. The double pipe part 2B formed in this manner and the pipe connection part 2C formed by being refracted from the pivot part 2A in the opposite direction to the double pipe part 2B. A first flow path 20 is formed inside the pivot 2 </ b> A of the main casing 2. The first flow path 20 is also present in the inner tube portion 26 of the double tube portion 2B, and is refracted at a right angle at the boundary portion between the pivot portion 2A and the double tube portion 2B. The double pipe part 2B has an inner pipe part 26 in which the first flow path 20 is contained and a second flow path 28 between the inner pipe part 26 and the outer pipe part 26. And an outer tube portion 27. In the opening edge portion 27A of the outer tube portion 27, an accommodation groove portion 27B that accommodates the sandwiched portion 11C of the diaphragm valve 11 is formed over the entire circumference. The pipe connecting portion 2C is connected to an external pipe 40 such as a branch pipe branched from the boom, for example, and a flow path 17A in the detent piping device 17 attached to the engagement hole 30 of the pipe connecting portion 2C is provided. , Communicated with the second flow path 28 of the double pipe portion 2B.

  Further, a diaphragm valve 11 that is entirely constituted by a fluoro rubber or other rubber material (an example of an elastic member) is disposed at a facing position of the valve seat 26 </ b> A that is an opening edge of the inner pipe portion 26. As shown in FIGS. 4 and 5, the diaphragm valve 11 seals the valve passage 26 </ b> A of the inner pipe portion 26 so as to be freely opened and closed, thereby blocking the first flow path 20 and the second flow path 28. The flat valve portion 11A that opens and closes the valve seat 26A of the inner pipe portion 26, the connecting plate portion 11B, the sandwiched portion 11C, and the misalignment prevention protrusion 11D are integrally formed. The connecting plate portion 11B extends from the entire outer periphery of the flat valve portion 11A and is inclined so as to spread outward in the radial direction as the distance from the flat valve portion 11A increases. 11 C of to-be-clamped parts are connected with the flat valve part 11A via the connection board part 11B, and are extended radially outward from the perimeter of the outer periphery of the connection board part 11B. The misalignment prevention protrusion 11D is formed so as to protrude from the central portion of the back surface 11E of the flat valve portion 11A. The sandwiched portion 11C has a substantially circular cross section when viewed in the diameter direction. The connecting plate portion 11B is formed at an angle θ with respect to the flat valve portion 11A when viewed from the side. The inclination angle θ is 40 degrees in this example. However, this inclination angle θ may be in the range of 20 to 60 degrees, for example.

  The pressing portion 19 that elastically biases the diaphragm valve 11 includes a valve pressing member 12 disposed on the back surface 11E side of the flat plate valve portion 11A of the diaphragm valve 11, and a valve support member 14 that holds the valve pressing member 12 movably. And a spring 13 that is interposed between the valve pressing member 12 and the valve support member 14 and elastically biases the valve pressing member 12. The valve support member 14 includes an accommodating portion 14A that accommodates the valve pressing member 12 and the spring 13, a through hole 14C that communicates the accommodating portion 14A with the outside, an opening edge portion 27A of the outer tube portion 27 that surrounds the accommodating portion 14A. And a sandwiching surface 14B for sandwiching the sandwiched portion 11C of the diaphragm valve 11. The outer peripheral edge of the clamping surface 14B is a flange that protrudes radially outward over the entire circumference. The sandwiching surface 14B of the valve support member 14 supports the sandwiched portion 11C of the diaphragm valve 11 so as to be liquid-sealed between the housing groove portion 27B of the outer tube portion 27 and support it. That is, the valve clamping part 33 that clamps the clamped part 11C of the diaphragm valve 11 accommodates the clamping surface 14B of the valve support member 14 and the clamped part 11C of the diaphragm valve 11 and the clamping surface 14B of the valve support member 14 It is comprised from the accommodation groove part 27B of the outer tube | pipe part 27 clamped between. The cap 15 has a through hole 15B through which the distal end portion of the valve support member 14 is inserted and the outer peripheral flange portion is locked, and a female screw portion 15A which is screwed with the male screw portion 27A of the outer tube portion 27. . The valve pressing member 12 includes a pressing surface 12B that supports the flat plate-like valve portion 11A of the diaphragm valve 11, a receiving hole 12A that is formed at the center of the pressing surface 12B, and that accommodates the displacement prevention protrusion 11D of the diaphragm valve 11. And a leg portion 12 </ b> C that protrudes from the back side of the housing hole 12 </ b> A.

  For example, the rotary head 3 having two nozzle mounting ports 21 and 22 is rotatably mounted on the pivot portion 2A. The pivot portion 2A and the rotary head 3 are sealed so as to be rotatable by an O-ring 35 attached to an outer circumferential groove portion 36 on the outer circumferential surface of the pivot portion 2A. A nozzle portion 41 having a nozzle plate, a nozzle cap, an O-ring (all not shown) and the like are attached to the nozzle attachment ports 21 and 22 of the rotary head 3, respectively. A cylindrical valve body 9 having a valve flow path 25 is interposed between the pivot portion 2A and the rotary head 3. The valve body 9 has a nozzle flow path 23 (or 24) connected to one nozzle mounting port 21 (or 22) and a first flow path 20 of the main casing 2 by rotation of the rotary head 3. The nozzle flow paths 23 and 24 are switched so as to close the nozzle flow path 24 (or 23) of the rotary head 3 connected to the other nozzle attachment port 22 (or 21).

  Next, an example of assembling the nozzle switching valve device 1 will be described. However, this is merely an example, and another assembly procedure may be used. First, in the main casing 2, the detent piping device 17 that has passed through the cap nut 16 is inserted into the engagement hole 30 of the piping connection portion 2 </ b> C, and the packing 18 is mounted in the female screw portion of the detent piping device 17. The The valve body 9 is mounted on the pivot 2A having the O-ring 10 fitted in the outer peripheral groove on one end side, and the lid member 7 having the O-ring 8 fitted in the outer peripheral groove is mounted on one end opening of the valve body 9. As a result, the assembly is assembled as one end side assembly. Then, the valve pressing member 12 with the spring 13 mounted on the back surface is accommodated in the accommodating portion 14A of the valve support member 14, the valve pressing member 12 is further pushed in, and the leg portion 12C becomes the through hole 14C of the valve support member 14. And is hooked at the edge of the hole. Thereby, the valve pressing member 12, the spring 13, and the valve support member 14 are integrated and assembled as the other end side assembly. The valve pressing member 12 is movable in the tube center direction C with respect to the valve support member 14.

  In the assembly at the other end, the connecting plate portion 11B of the diaphragm valve 11 is accommodated in the accommodation hole 12A of the valve pressing member 12, and the back surface 11E of the diaphragm valve 11 is placed on the pressing surface 12B of the valve pressing member 12. The valve support member 14 is mounted in the through hole 15 </ b> B of the cap 15. Thereafter, the flat valve portion 11A of the diaphragm valve 11 is applied to the valve seat 26A of the inner tube portion 26, and the female screw portion 15A of the cap 15 is screwed to the male screw portion 29 on the outer peripheral surface of the outer tube portion 27. . At this time, the sandwiched portion 11C of the diaphragm valve 11 is sandwiched between the sandwiching surface 14B of the valve support member 14 and the inner wall of the housing groove portion 27B and elastically deformed, and the sandwiching surface 14B of the valve support member 14 and the outer tube portion 27 The gap with the opening edge portion 27A is sealed. On the other hand, the rotary head 3 is mounted on the outer periphery of the one end side assembly including the pivot portion 2A described above, and both pins of the slide locking pin 6 are inserted into the insertion holes 32, 32 of the rotary head 3 so that the outer periphery of the pivot portion 2A is inserted. It is hooked at the groove 31. Thereby, the rotary head 3 is prevented from coming off in the direction of the axis D with respect to the pivot 2A, and is pivotally supported so as to be rotatable in the circumferential direction (arrow R direction). In the rotary head 3, the packing 4 is mounted on the outer periphery of the nozzle mounting port 22, and the packing 5 is mounted on the outer periphery of the nozzle mounting port 23. In this way, the assembly of the nozzle switching valve device 1 is completed.

Next, the operation of the nozzle switching valve device 1 configured as described above will be described.
In general, nozzle portions 41 having different spraying modes, for example, for fine droplets / wide-angle spraying and for coarse droplets / narrow-angle spraying, are attached to the nozzle mounting ports 21, 22. Further, the pipe connecting portion 2C of the main casing 2 is connected to the branch pipe of the boom. Therefore, when the power pump is driven and the boom cock is opened (both are not shown), a chemical solution having a pressure of, for example, about 3 MPa flows from the boom into the second flow path 28 via the pipe connecting portion 2C. In this case, the sandwiched portion 11C of the diaphragm 11 is formed in a substantially circular cross-sectional shape before being sandwiched. Therefore, when the sandwiched portion 11C is sandwiched between the opening edge portion 27A of the outer tube portion 27 and the sandwiching surface 14B of the valve support member 14. The clamped portion 11C, which was in the line contact state at the time of light contact, is elastically deformed and flattened after the clamping, and a part thereof is in a surface contact state. However, there is still a non-contact portion other than the surface contact portion, which is prepared for further clamping pressure. As a result, even if the liquid pressure of the chemical solution is applied, the gap between the clamped portion 11C of the diaphragm valve 11 and the opening edge portion 27A of the outer tube portion 27 is tightly sealed, and liquid leakage from these to the outside occurs. Absent.

Then, the chemical solution in the second flow path 28 presses the connecting plate portion 11B of the diaphragm valve 11 obliquely with respect to the tube core C, overcomes the elastic biasing force of the spring 13, and forms a flat plate shape of the diaphragm valve 11. The valve portion 11A and the valve pressing member 12 are smoothly pushed down. Thereby, when the flat plate-like valve portion 11A of the diaphragm valve 11 starts to be separated from the valve seat 26A, the whole flat plate-like valve portion 11A is pressurized, and the valve seat 26A is further opened. By opening the valve seat 26A in this manner, the chemical liquid that has flowed into the first flow path 20 reaches the pivot 2A, passes through the valve flow path 25 of the valve body 9, and the nozzle mounting port (currently selected for use) ( For example, it passes through 21) and is ejected from the nozzle part 41 to the outside.
When switching the nozzle part 41 to be used, the power pump is once stopped and the liquid pressure of the chemical solution is lowered. Thereby, the liquid pressure of the chemical liquid falls below the elastic biasing force of the spring 13, and the diaphragm valve 11 closes the valve seat 26A. Thereafter, the rotary head 3 is rotated to connect the nozzle attachment port (for example, 22) to which the desired nozzle portion 41 is attached to the valve flow path 25 of the valve body 9. Subsequently, when the power pump is restarted, the chemical liquid is ejected from the nozzle portion 41 of the nozzle mounting port 22.

  As described above, according to the nozzle switching valve device 1, the side section of the sandwiched portion 11C of the diaphragm valve 11 made of an elastic member is formed in a substantially circular shape. When sandwiched between the opening edge portion 27A of the tube portion 27 and the sandwiching surface 14B of the valve support member 14, the sandwiched portion 11C is elastically deformed and flattened, and a part of the surface, not the entire surface, is in a surface contact state. Remains. Therefore, not only when the hydraulic pressure in the second flow path 28 is low, such as when the power pump is stopped or when the cock is closed, but also when the hydraulic pressure is high, such as when the power pump is driven or the cock is opened. However, the gap between the sandwiched portion 11C of the diaphragm valve 11 and the opening edge portion 27A of the outer tube portion 27 can always be tightly sealed. Thereby, it is possible to reliably avoid leakage of liquid from the outside to the outside.

In the above-described embodiment, the cross-sectional shape of the sandwiched portion 11C of the diaphragm valve 11 is formed in a substantially circular shape. However, the substantially circular cross-sectional shape of the sandwiched portion referred to in the present invention is only a shape close to a perfect circle. In addition, an oval shape, an oval shape, a rhombus shape with rounded corners, and the like are also included.
In the above description, the number of nozzle attachment ports in the rotary head is two, but this is not limited in the present invention, and may be three or more as long as the number can be arranged in the rotary head.

DESCRIPTION OF SYMBOLS 1 Nozzle switching valve apparatus 2 Main body casing 2A Pivot part 2B Double pipe part 2C Piping connection part 3 Rotating head 9 Valve body 11 Diaphragm valve 11A Flat plate part 11C Clamping part 12 Valve pressing member 12B Pressing surface 13 Spring 14 Valve support Member 14B Nipping surface 17A Channel 19 Pressing portion 20 First channel 21, 22 Nozzle mounting port 23, 24 Nozzle channel 25 Valve channel 26 Inner tube portion 26A Valve seat 27 Outer tube portion 27A Opening edge portion 27B Accommodating groove portion 28 Second flow path 33 Valve clamping part 40 External piping 41 Nozzle part C Core R Arrow

Claims (2)

A plate-shaped valve portion that is made of an elastic member and opens and closes the valve seat of the flow path formed in the nozzle switching valve device, and extends from the entire outer periphery of the plate-shaped valve portion in the nozzle switching valve device. A diaphragm valve comprising: a sandwiched portion sandwiched between the first portion and the second portion, wherein a section in a valve diameter direction of the sandwiched portion is formed in a substantially circular sectional shape. A rotary head having a plurality of nozzle mounting ports is rotatably provided at one end of the main casing having the first flow path therein,
Between the one end of the main body casing and the rotary head, the rotation head rotates to connect the flow path for nozzles of the rotary head connected to one nozzle mounting opening and the first flow path of the main body casing, and to attach other nozzles. A valve body that switches the nozzle flow path to close the nozzle flow path of the rotating head connected to the mouth is interposed,
An inner tube portion in which the first flow path is provided in the other end portion of the main body casing; and an outer tube portion which is disposed outside the inner tube portion and in which the second flow path is provided between the inner tube portion and the inner tube portion. A double pipe part consisting of
A pipe connection part connected to an external pipe is provided in the main casing in communication with the second flow path of the double pipe part,
2. The diaphragm valve according to claim 1, wherein a valve seat which is an opening edge portion of the inner pipe portion is sealed so as to be freely opened and closed, and the first flow path and the second flow path are blocked, and the diaphragm valve is elastically biased. A valve that supports the pressing portion pressed against the valve seat and the sandwiched portion formed on the entire periphery of the diaphragm valve in a liquid-sealed manner between the opening edge of the outer tube portion of the double tube portion A nozzle switching valve device comprising: a support member;

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