JPH0355008Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is suitable for use in architectural equipment and industrial piping, such as water and hot water supply piping, cold and hot water piping for air conditioning, medium and sewage piping, air piping, and gas piping. The present invention relates to butterfly valves used in the present invention, and in particular to the structure and materials of the valve body.

(Prior art) The valve box of a butterfly valve is generally made by machining a cast product of ferrous or non-ferrous metal, but it is also made by pressing a metal plate to reduce weight and processing. Sometimes it happens. Figure 6 is an example of this,
Since the gasket accommodating portion is made by expanding the diameter by pressing, the plate thickness becomes thinner, resulting in poor strength and cracks. 7th
The figure is a longitudinal sectional view showing an embodiment of the butterfly valve described in Japanese Patent Application Laid-Open No. 62-63279. In this case as well, the inner shell 104 is expanded in diameter to form a gasket housing portion 107. Although the lack of strength in this portion is compensated for by the outer shell 105, it has drawbacks such as cracks occurring in this portion due to diameter expansion by pressing, and cracks occurring due to residual stress.

(Problems to be solved by the invention) The invention solves the problem of the thinning of the valve body of the butterfly valve made by pressing a metal plate, the lack of strength caused by this, the occurrence of cracks, and the cracks caused by residual stress. This is an attempt to solve the problem of the occurrence of

(Means for solving the problems) In order to solve the above problems, the present invention is configured as follows.

That is, an annular valve body, a valve stem that diametrically passes through a flow path at the center of the valve body, and a valve stem that is fixed to the valve stem and rotates the valve stem approximately 90 degrees to open the flow path. In a butterfly valve consisting of a substantially disk-shaped valve body that opens and closes, the valve box consists of an inner cylinder and an outer cylinder,
The inner cylinder has a substantially cylindrical shape, and the outer cylinder has a substantially cylindrical cylindrical portion having approximately the same length as the inner cylinder, which is fitted concentrically with the inner cylinder, and a cylindrical portion extending from both ends of the cylindrical portion to the end periphery of the inner cylinder. It consists of a pair of annular gasket accommodating parts each having a C-shaped cross section with facing concave surfaces on the sides, and the inner periphery of each of the gasket accommodating parts is closely fixed to the end periphery of each of the inner peripheries.

(Function) Since the present invention is configured as described above, the inner cylinder does not expand in diameter, and the outer cylinder does not expand in diameter but only contracts in diameter. Moreover, since the material is not stretched but only compressed by pressing, cracks do not occur and cracks do not occur due to residual stress.
Furthermore, the gasket accommodating portion is supported by the cylindrical portion of the approximately cylindrical outer cylinder and the approximately cylindrical inner cylinder, so that it will not deform when the valve is sandwiched between a pair of flanges and tightened. , is solid enough.

(Example) Fig. 1 is a vertical sectional view showing an example of the present invention.
FIG. 2 is a partially enlarged sectional view of FIG. 1. Also,
3 to 5 are partially enlarged sectional views showing other embodiments of the present invention.

In FIGS. 1 to 5, 1 is an annular valve box;
2 is a flow path in the valve box 1, and 3 is a flow path 2 in the center of the valve box 1.
4 is a valve stem that penetrates through the valve stem 3 in the diametrical direction, and 4 is a substantially disk-shaped valve body that is fixed to the valve stem 3 and opens and closes the flow path 2 by rotating the valve stem 3 approximately 90 degrees. , the butterfly valve is composed of a valve box 1, a valve stem 3, and a valve body 4.

5 is a substantially cylindrical inner cylinder; 6 is an outer cylinder;
The inner cylinder 5 is fitted concentrically with a substantially cylindrical cylindrical part 6a having approximately the same length as the inner cylinder 5, and a substantially cylindrical part 6a with a concave surface facing outward from both ends of the cylindrical part 6a toward the end periphery 5a of the inner cylinder 5. It consists of a pair of annular gasket accommodating portions 6b having a C-shaped cross section, and the inner periphery 6c of the gasket accommodating portion 6b is tightly fixed to each end periphery 5a of the inner cylinder 5.

7 is an annular gasket made of an elastic material such as rubber, which is attached to the gasket accommodating portion 6b of the outer cylinder 6;
9 is an O-ring that seals the valve stem 3, and 9a, 9b, and 9c are bearings that support the valve stem 3.

2 to 5 show an embodiment in which the inner periphery 6c of the gasket accommodating portion 6b of the outer cylinder 6 is sealed to the end periphery 5a of the inner cylinder 5. In the case of the embodiment, the gasket accommodating portion 6b
The inner periphery 6c of the inner cylinder 5 and the end periphery 5a of the inner cylinder 5 are overlapped and fixed by groove welding.

FIG. 3 is almost the same as FIG. 2, with fillet welding performed.

In FIG. 4, the end periphery 5a of the inner cylinder 5 is folded back and the inner periphery 6c of the gasket accommodating portion 6b is sandwiched and fixed thereto.

Further, FIG. 5 shows the gasket accommodating portion 6b of the outer cylinder 6.
Fold back the inner circumference 6c and attach the end circumference 5a of the inner cylinder 5.
It is stuck in place by sandwiching it.

In the embodiment shown in FIGS. 2 to 5 above,
The thickness and material of the inner cylinder 5 and outer cylinder 6 can be changed as appropriate depending on the type and pressure of the fluid.

Next, the operation of the embodiment shown in FIGS. 1 to 5 will be explained.

In this invention, the inner cylinder 5 does not expand in diameter, and the outer cylinder 6 does not expand in diameter but only contracts in diameter. Since only compression is performed without tension, no cracks occur and no cracks occur due to residual stress. Furthermore, the gasket accommodating portion 6b is supported by the cylindrical portion 6a of the substantially cylindrical outer cylinder 6 and the substantially cylindrical inner cylinder 5, so that when the valve is sandwiched between a pair of flanges and tightened, It will not deform and is strong enough.

In the structure of the present invention, since a jacket space is formed between the inner cylinder 5 and the outer cylinder 6, it can also be used as a valve with a jacket that heats the space by passing steam or a heat medium therein.

(Effects of the invention) Since the present invention is constructed and operates as described above, excellent effects as described below can be obtained.

That is, (1) Thin parts cannot be created by pressing.

(2) Defects such as cracks due to press working, cracks and corrosion due to residual stress are less likely to occur.

(3) Deformation of the valve box is less likely to occur.

(4) Plate thickness and materials can be selected rationally, allowing for rational and economical design.

(5) Can also be used as a jacket valve.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention;
Fig. 2 is a partially enlarged sectional view of Fig. 1, Figs. 3 to 5 are partially enlarged sectional views showing other embodiments of the present invention, and Figs. FIG. 3 is a longitudinal cross-sectional view showing an example of a valve. 1... Valve box, 2... Channel, 3... Valve stem, 4...
Valve body, 5... Inner cylinder, 5a... End circumference of inner cylinder, 6...
Outer cylinder, 6a... Cylindrical part of the outer cylinder, 6b... Gasket accommodating part of the outer cylinder, 6c... Inner periphery of the gasket accommodating part.

Claims (1)

[Claims for Utility Model Registration] (1) An annular valve body, a valve stem that diametrically passes through the flow path in the center of the valve body, and a valve stem that is fixed to the valve stem and rotates the valve stem approximately 90 degrees. In a butterfly valve consisting of a substantially disk-shaped valve body that opens and closes the flow path by moving, the valve box consists of an inner cylinder and an outer cylinder,
The inner cylinder has a substantially cylindrical shape, and the outer cylinder has a substantially cylindrical cylindrical portion having approximately the same length as the inner cylinder, which is fitted concentrically with the inner cylinder, and a cylindrical portion extending from both ends of the cylindrical portion to the end periphery of the inner cylinder. It is characterized by comprising a pair of annular gasket accommodating parts each having a C-shaped cross section with facing concave surfaces as the sides, and the inner periphery of each of the gasket accommodating parts is closely fixed to the end periphery of each of the inner peripheries. Butterfly valve. (2) The butterfly valve according to claim 1, wherein the inner periphery of the gasket accommodating portion of the outer cylinder and the end periphery of the inner cylinder are overlapped and fixed. (3) The butterfly valve according to claim 1, wherein the end periphery of the inner cylinder is folded back and the inner periphery of the gasket accommodating portion of the outer cylinder is sandwiched and fixed therebetween. (4) The butterfly valve according to claim 1, wherein the inner periphery of the gasket accommodating portion of the outer cylinder is folded back and the end periphery of the inner cylinder is fixed therebetween. (5) The butterfly valve according to claim 1, wherein the material of the outer cylinder is different from the material of the inner cylinder.