JP2007239861A - Check valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a check valve in which mounting of a switch and its position adjustment are easy. <P>SOLUTION: In the swing type check valve having a no feed water contact point device for detecting whether or not water is fed by operation of a pump, the no feed water contact point device is equipped with a cam 20 fixed to a valve rod 5 extending to the outside of a valve box 2, a switch 21 for detecting opening of a valve element 3 from the movement of the cam 20, and a mounting case 25 in which the switch 21 is mounted. The switch 21 is provided with screws 23 and 24 at diagonal position of a mounting face formed substantially in a rectangular shape. In the case 25, screw grooves 29a and 29b, in which the mounting screws 23 and 24 are movable, are formed extending in parallel on one side and another side of a fixed plate 27 toward the cam 20. The fixed plate 27 is formed with one side inclining with respect to another side. A length L1 from one side to the screw groove inlet of the other side is set shorter than a length L2 between the screws on the diagonal line. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a swing type check valve having a non-water-feeding contact device that detects the presence or absence of water feeding by the operation of a pump.

  The check valve of the above type cannot visually recognize the open / closed state of the valve body. If no water is supplied even if the water pump is activated, it means that the pump is idling, and the pump will burn if left unknowingly. Therefore, it is already known to detect the idling of the pump by providing a non-water-feeding contact device provided with a switch for detecting the opening of the valve element in the check valve that opens when the pump is operated and water is supplied.

  In this type of non-water-feed contact device, a cam is fixed to a valve rod extending outside the valve box, and when the valve body is opened, the switch is turned on by the rotating cam to detect the opening of the valve body. At this time, when the opening angle of the valve body reaches a predetermined angle, the non-water-feed contact device is assembled to the valve so that the switch is turned on by the cam rotated at that time. At this time, when the valve body is opened to a certain angle (for example, 15 degrees), it is required that the switch be surely operated. It is necessary to adjust one and confirm.

Japanese Utility Model Publication No. 46-33516 Japanese Utility Model Publication No. 53-42807

  In the conventional check valve, as described in Patent Documents 1 and 2, in order to prevent the backflow and the water hammer effect, the valve rod is extended outwardly in order to close the check valve rapidly and the outside of the valve box. A spring base or case is provided on the extension of the valve stem to attach the spring. The switch is housed in a cover-covered case as a protective measure when used outdoors, but the case itself is required to be reduced in size in all of its length, width, and height. Yes.

  However, when the distance to the valve box is reduced due to a demand for reducing the height of the case, tightening of the nut for fixing the switch has been a troublesome work. In addition, there is a problem that it is difficult to mount the switch while adjusting the position of the switch.

  In view of the above-described conventional circumstances, an object of the present invention is to provide a check valve in which a switch can be easily attached and its position can be adjusted.

  In order to achieve the above object, the present invention provides a swing type check valve having a non-water supply contact device for detecting the presence or absence of water supply by the operation of a pump, wherein the non-water supply contact device extends outside the valve box. A cam that is fixed to the valve stem; a switch that detects the opening of the valve body from the movement of the cam; and a mounting case to which the switch is mounted. The mounting case is provided with a mounting screw, and the mounting case is formed by tilting the other side with respect to one side, and the parallel mounting screw extending in the direction toward the cam is movable on one side and the other side. A check valve is proposed in which a screw groove is formed, and the length from one side to the screw groove inlet on the other side is set shorter than the length between the diagonal screws.

  According to the present invention, the case is formed into a hexahedron with the mounting member and a cover covering the mounting member, and the mounting member has two surfaces, a mounting plate and a rising plate with one edge of the mounting plate raised. The cover has four surfaces, an upper surface, both side surfaces extending from the upper surface to both sides, and a side surface facing the rising plate, and both side surfaces from the upper surface of the cover are formed along the rising plate, and It is effective if the lower side edge of the cover is formed with a bend that is locked to the side edge of the mounting plate.

  According to the configuration of the present invention, it is possible to easily adjust the position of the switch even if the work space of the attachment portion is narrow, and also to easily fix after the adjustment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a cross-sectional explanatory view of a check valve according to the present invention.
In FIG. 1, reference numeral 1 is a check valve, 2 is its valve box, and 3 is a valve body. As shown in FIGS. 1 to 3, a valve body arm (not shown) formed on the valve body 3 is fixed to the valve body 5. The valve stem 5 is mounted on the valve box 2 by a bearing bush 6 so as to be rotatable and movable in the axial direction. Since this valve stem 5 penetrates through the valve box 2 and protrudes outward, a ground mechanism having an O-ring or the like is provided to prevent leakage of pressure water.

  A spring lever arm 10 is fixed by setscrews 11 and 12 to a portion of the valve stem 5 that appears outside the valve box 2, that is, outside the gland mechanism, and pins 13 are provided near both ends of the spring lever arm 10. 14 are attached. Further, as shown in FIG. 3, the valve box 2 is provided with a spring base 15 formed in a substantially diamond shape, and the spring base 15 is fixed to the valve box 2 with a bolt (not shown). On the spring base 15, springs 16 and 17 as elastic urging means are engaged with pins 18 and 19 provided near both ends of the spring base 15 and the pins 13 and 14 of the spring lever arm 10 described above. Attached. That is, the spring 16 is spanned between the pin 18 of the spring base 15 and the pin 13 of the spring lever arm 10, and the spring 17 is spanned between the pin 19 of the spring base 15 and the pin 14 of the spring lever arm 10. It has been. The springs 16 and 17 are locked to the pins 13, 14, 18, and 19 via bearings.

  The two springs 16 and 17 are tension springs, and both cooperate to act so as to rotate the spring lever arm 10 clockwise in FIG. Therefore, by applying a clockwise rotational moment to the valve stem 5, this spring force is transmitted to the valve body 3 via the valve stem 5 and the valve body arm, and acts to seat the valve body 3 on the valve seat 4. ing.

  In such a check valve, there is known a non-water-feeding contact device that detects the opening of the valve body by switching the switch through a cam when the valve body is opened at a predetermined angle. I explained earlier that there is a difficult problem.

  Therefore, as shown in FIG. 4, the non-water-feed contact device of the present embodiment uses a switch 21 as a microswitch that is switched on when the hinge lever 22 is pushed and is turned on in this example. Is formed in a substantially rectangular shape, and mounting screws 23 and 24 are implanted at diagonal positions on the mounting surface 22 thereof. As shown in FIG. 5, the switch 21 is attached to an attachment case 25 provided on the spring base 15.

  Further, as shown in FIG. 2, the valve stem 5 reaches the mounting case 25 to which the switch 21 is attached, and the valve stem 5 at a position corresponding to the mounting position of the switch 21 is as shown in FIG. The cam 20 that turns on the switch 21 by rotation is fixed by a screw or the like.

  As shown in FIGS. 2 and 7, the attachment case 25 is formed in a hexahedron with a substrate portion 26 as an attachment member to which the switch 21 is attached and a cover portion 30 that covers and protects the switch 21. The board portion 26 has a fixed plate 27 to which the switch 21 is fixed, and a rising plate 28 that is raised on one side. On the other hand, the cover portion 30 has four surfaces, that is, an upper surface 31, side surfaces 32 and 33 that extend from the upper surface 31 to both sides, and a side surface 34 that faces the rising plate 28.

  The fixing plate 27 of the base plate part 26 is formed with screw grooves 29a and 29b on one side 27a and the other side 27b in which parallel mounting screws 23 and 24 extending in the direction toward the cam 20 are movable.

  In order to attach the switch 21 to the attachment case 25, a nut (not shown) is lightly screwed onto the attachment screws 23 and 24 of the switch 21 and temporarily engaged with the screw grooves 29 a and 29 b of the fixing plate 27. At this time, the screw groove 29a is formed on one side 27a of the fixed plate 27, and the screw groove 29b is formed on the other side 27b of the fixed plate 27, respectively, but one side 26a of the screw grooves 29a and 29b is provided to enable the temporary engagement. To the other side 26b is set to be shorter than the length L2 between the diagonal screws 23 and 24 in the switch 21. With this setting, even when nuts (not shown) are engaged with the screws 23 and 24 of the switch 21, the screws 23 and 24 straddle the fixing plate 27, and the screws 23 are screw grooves 29a and 24. Can be loosely engaged with the screw grooves 29b. That is, the length L1 from one side 27a to the other side 27b of the fixing plate 27 is shorter than the length L2 between the diagonal screws 23 and 24 in the switch 21, so that the nut 23 is engaged with the screws 23 and 24. The switch 21 can be loosely engaged with the fixing plate 27 from the direction of arrow A in FIG.

  Since the switch 21 temporarily engaged with the fixed plate 27 can move in the contact / separation direction with respect to the cam 20, the position adjustment at which the switch 21 is operated by the cam 20 is easily performed. It is fixed by tightening 24 nuts.

  Thus, the non-water-feed contact device of the present embodiment can engage the screws 23 and 24 screwed with the nuts in advance with the screw grooves 29a and 29b of the fixing plate 27, and thus the switch 21 whose position has been adjusted. Need only have a working space for tightening a nut through a screwed washer, and the mounting case 25 can be downsized.

The non-water supply contact device fixed after the adjustment of the switch 21 is provided with the cover portion 30 to protect the switch 21. In order to facilitate the attachment of the cover part 30, as shown in FIG. 7, bends 32 a and 33 a that are locked to the side edges of the substrate part 26 are formed on both side surfaces 32 and 33 of the cover part 30. When the cover part 30 is attached to the board part 26, the cover part 30 can be slid in a state where the bends 32 a and 33 a of the cover part 30 are engaged with the side edges of the board part 26. The cover portion 30 is temporarily fixed by fitting this portion to the upper edge of the rising plate 28. Then, if the cover part is fixed to the board part 26 with screws or the like, the attachment of the attachment case 25 is completed.
Note that the bends 32a and 33a shown in FIG. 7 are exaggerated for easy understanding, and the bends 32a and 33a may be small round shapes. Further, the edges of the substrate portion 26 facing the bends 32a and 33a are processed so as to conform to the shapes of the bends 32a and 33a. By this processing, when the cover portion 30 is attached to the substrate portion 26, the lower surface of the substrate portion 26 and the lower end of the cover portion 30 in the drawing can be made the same surface.

It is a longitudinal cross-sectional view of the check valve according to the present invention. It is a cross-sectional view of the check valve according to the present invention. It is a front view which shows the spring unit part of the check valve of this invention. It is explanatory drawing of the switch used for the non-water-feeding contact apparatus of the check valve of this invention. It is front explanatory drawing of a non-water-feeding contact apparatus. It is explanatory drawing of an attachment case. It is a disassembled perspective view of an attachment case.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Check valve 2 Valve box 3 Valve body 4 Valve seat 5 Valve rod 20 Cam 21 Switch 23, 24 Mounting screw 25 Mounting case 26 Substrate part 27 Fixing plate 28 Rising plate 29a, 29b Screw groove 30 Cover part

Claims (2)

In a swing type check valve having a non-water-feeding contact device that detects the presence or absence of water feeding by the operation of a pump,
A cam fixed to a valve stem that extends outside the valve box, the switch that detects the opening of the valve body from the movement of the cam, and a mounting member to which the switch is attached. Prepared,
The switch is provided with mounting screws at diagonal positions on the mounting surface formed in a substantially rectangular shape,
The mounting member is formed with a mounting groove formed on the other side inclined with respect to one side, and on one side and the other side, a screw groove is formed that can move the parallel mounting screw extending in the direction toward the cam,
A check valve characterized in that a length from one side of the screw groove to the other side is set shorter than a length between diagonal screws.   2. The check valve according to claim 1, wherein the case is formed into a hexahedron by the attachment member and a cover covering the attachment member, and the attachment member is a rising plate formed by raising one end edge of the attachment plate and the attachment plate. The cover has four surfaces, an upper surface, both side surfaces extending from the upper surface to both sides and a side surface facing the rising plate, and the both sides from the upper surface of the cover are along the rising plate. A check valve characterized by being formed and formed on both side surfaces of the cover with a bend at the lower edge and locked to the side edge of the mounting plate.

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