JP2005036889A - Check valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that the distance between both faces (the height) of a valve box becomes long, also, a large number of components are required, the shape of the valve box becomes large, and the weight is increased in a conventional lift type check valve. <P>SOLUTION: The check valve is composed of the valve box, to which a water passing port is provided to the upper part and the lower part, a valve body, which is internally mounted to the valve box and to which a circular valve plate and a valve rod vertically extended from the center of the valve plate are provided, seat packing mounted to the lower side at the peripheral part of the valve plate, a valve seat brought into contact with the seat packing, an upper guide, which is supported by the inner wall of the valve box and slidably supports the lower part of the valve rod, a lower guide, which is supported by the inner wall of the valve box and slidably supports the lower part of the valve rod, and a spring resiliently mounted between the upper guide and the valve plate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a quick-closing type lift check valve incorporating a spring to prevent a water hammer.

  As a lift type check valve with a built-in spring to prevent a water hammer, there is a structure shown in FIG. In FIG. 2, 21 is a valve box, 22 is a valve body, 23 is a valve seat, 24 is a valve rod, 25 is a lower guide, 26 is an upper guide, 27 is a valve spring, 28 is a buffer umbrella, 29 is a seat packing, 30 Is a bypass valve. In such an apparatus, water that pressurizes the lower surface of the valve body 22 pushes up the valve body 22 against the valve spring 27 and flows upward through the annular space between the valve body 22 and the valve seat 23. When the water flow under the valve body 22 is stopped, the valve body 22 is lowered by the elasticity of the valve spring 27 and the valve is closed. At this time, the water on the upper side of the valve body 22 has not started to descend, so that no water hammer is generated. The lower guide 25 and the upper guide 26 prevent the eccentricity and inclination of the valve body 22.

In the lift type check valve shown in FIG. 2, since the lower guide 25 is provided on the lower side of the valve body 22, the distance (height) L between the faces of the valve box 21 is increased, and the number of parts is large. Therefore, there is a problem that the shape of the valve box 21 is increased and the weight is increased.
An object of the present invention is to eliminate the above-mentioned problems by reducing the distance L between the faces of the valve box and further reducing the number of parts.

  A valve body with water outlets at the top and bottom, a valve body with a circular valve plate and a valve stem extending up and down at the center of the valve plate, and a lower part of the periphery of the valve plate Seat packing, a valve seat that contacts the seat packing, an upper guide that is supported by the inner wall of the valve box and that slidably supports the lower part of the valve stem, and a lower part of the valve stem that is supported by the inner wall of the valve box In a check valve comprising a lower guide that slidably supports and a spring that is elastically mounted between the upper guide and the valve plate, the valve seat and the lower guide are formed of a single component.

  According to the present invention, the valve body can be moved up and down smoothly and quickly, so that the water hammer can be prevented smoothly. By constituting the valve seat and the lower guide with a single part, the number of parts is reduced and the structure is simplified.

  The present invention will be described in detail based on the embodiment shown in FIG.

  1 is a valve box which is cast from cast iron, stainless steel or the like and has upper and lower water inlets 2 and 3, and 4 is a valve comprising a circular valve plate 5 and a valve rod 6 extending vertically from the center of the valve plate 5. The body, 7 is a seat packing mounted on the lower side of the periphery of the valve plate 5, 8 is a valve seat that contacts the seat packing 7, 9 is an upper guide that slidably supports the upper portion of the valve stem 6, and 10 is a valve stem A lower guide for slidably supporting the lower portion of 6, 11 is a spring elastically mounted between the upper guide 9 and the valve plate 5, 12 is a bypass provided in the valve box 1, and 13 opens and closes the bypass 12. It is a bypass valve.

  In such an apparatus, the water that pressurizes the lower surface of the valve body 4 pushes up the valve body 4 against the spring 11 and flows upward between the seat packing 7 of the valve plate 5 and the valve seat 8. . When the water flow under the valve body 4 is stopped, the valve body 4 is lowered by the elasticity of the spring 11 and the valve seat 8 is closed. At this time, the water on the upper side of the valve body 4 has not started to descend, so that no water hammer is generated. Since the upper guide 9 and the lower guide 10 guide the upper and lower portions of the valve stem 6, the valve body 4 is smoothly moved up and down without causing eccentricity and tilting.

The longitudinal cross-sectional view in the Example of this invention check valve | bulb. The longitudinal cross-sectional view of the conventional check valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve box 2, 3 Water flow port 4 Valve body 5 Valve plate 6 Valve rod 7 Seat packing 8 Valve seat 9 Upper guide 10 Lower guide

Claims (1)

Valve box (1) provided with water inlets (2, 3) at the top and bottom, and a valve that is built in the valve box (1) and that extends vertically around the center of the circular valve plate (5) and valve plate (5) A valve body (4) provided with a rod (6), a seat packing (7) mounted on the lower side of the peripheral portion of the valve plate (5), a valve seat (8) contacting the seat packing (7), An upper guide (9) supported by the inner wall of the valve box (1) and slidably supporting the lower part of the valve stem (6), and supported by the inner wall of the valve box (1) and lower of the valve stem (6) In a check valve comprising a lower guide (10) for slidably supporting a spring and a spring (11) elastically mounted between the upper guide (9) and the valve plate (5), the valve seat (8) A check valve characterized in that the lower guide (10) is composed of a single part.

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