JPS5922379Y2 - butterfly valve - Google Patents

Description

[Detailed explanation of the idea] Industrial applications The present invention relates to a butterfly valve.

Conventional structure and its problems In the past, O-rings were used in butterfly valves to improve the sealing effect between the shaft and the valve seat, as shown in Figure 6. There were disadvantages such as the liquid that entered the unit was difficult to clean, and the number of parts required for assembly increased.

Purpose of the Invention It is an object of the present invention to provide a butterfly valve that improves the sealing effect between a valve plate and a valve seat that open and close a fluid passage, and that is easy to disassemble and assemble.

Structure of the invention The present invention eliminates the drawbacks of the conventional example as mentioned above.
An annular valve seat made of rubber, synthetic resin, or other elastic material that penetrates the shaft of a valve plate that opens and closes a fluid passage, and is formed into a tapered shape so that it becomes thinner near the fluid passage; A fluid fluid having an annular valve box that is split into two at the outer peripheral edge of the seat, tapered so that the outer peripheral side is thinner, and that is inserted through the shaft of the valve plate, and an annular tightening flange at the opposing inner end. a passage pipe, a tapered portion provided on the inner surface of the tightening flange portion to correspond to the tapered shape of the valve seat and the valve box, and a ring-shaped convex portion provided on a portion of the outer peripheral surface of the shaft portion. Alternatively, it is composed of a concave portion and a concave portion or convex portion provided on the valve seat at a position corresponding to the ring-shaped convex portion or concave portion.

Since the present invention has the above-mentioned configuration, the tightening flange of the fluid passage pipe can be simply tightened and fixed with bolts, nuts, etc., and the outer circumferential side of the valve seat has a tapered shape between the valve body and the tightening flange. The valve seat is reliably guarded, and the tapered shape of the valve seat and the tapered shape of the tightening flange corresponding to the valve seat work to expand the valve seat in the inner diameter direction, improving the sealing effect between the valve plate and the valve plate. , the tightening flange of the fluid passage pipe can be tightened or removed simply by tightening or removing the
The valve box, valve plate, etc. can now be tightened or disassembled all at once.

Furthermore, since the valve seat and the shaft portion of the valve plate have corresponding concave portions or convex portions, the sealing effect can be improved.

Description of examples The drawings shown as examples will be explained below.

A valve plate 1 opens and closes the fluid passage 2.

Reference numeral 3 has a ring-shaped convex portion 4 on a part of the outer periphery of the shaft portion, one end of which is connected to the valve plate 1, and the other end of which protrudes outward from the tightening flange portion 6 of the fluid passage pipe 5.

7 is a valve seat, which has a through hole with a slightly smaller diameter than the diameter of the shaft portion 3;
Made of highly elastic materials such as rubber and synthetic resin,
The shaft portion 3 is press-fitted into the through hole and inserted into the tightening flange portion 6, and the sealing surface with the shaft portion 3 is deformed and tightly adhered with a large contact pressure.

A valve box 8 bears the shaft 3 together with the valve seat 7, and is fixed by bolts 9 and nuts 10 such that the shaft 3 and the valve seat 7 are clamped together by the tightening flange.

When the tightening flange portion 6 of the fluid passage pipe is tightened and fixed by bolts 9 and 10, the outer circumferential side of the valve seat 7 is reliably guarded, and the tapered shape creates a slight bulge toward the inner circumferential side to improve the sealing effect. did.

Further, although a shaft portion having a convex portion on the outer circumferential surface as shown in FIG. 2A is used, a ring-shaped concave portion 11 may be formed on the outer circumferential surface as shown in FIG. 2B.

Furthermore, the hole for penetrating the shaft 3 provided in the valve seat 7 is not limited to a flat cylindrical shape, but may have a convex portion 12 or four portions 13 on the inner surface of the hole as shown in Fig. 3A and B. May be used.

When at least one of the shaft portion 3 and the hole in the valve seat 7 has a recess or a convex portion and is press-fitted, the contact pressure can be increased at the convex portion or the four-part forming portion, and a reliable sealing effect can be achieved.

Therefore, in the case of any of the above shapes of the shaft portion, which shape of the hole of the valve seat is used can be arbitrarily determined depending on the pressure, temperature, viscosity of the fluid, and other properties of the fluid.

For example, when the fluid is at low pressure, a shaft with a convex portion (Fig. 2A)
), and when the fluid is at high pressure, a hole with a convex portion (Fig. 3 A) is used relative to the shaft (Fig. 2 A), which has a convex portion. .

If the contact pressure between the shaft and the valve seat is too high, there will be no fluid leakage, but the contact resistance will increase, making it difficult for the shaft to rotate and causing problems in opening and closing the valve.
It is desirable to use one with an appropriate contact pressure depending on the fluid.

Figures 4A, B and 5 show other embodiments.
In FIG. 4, a recess 14 having a substantially V-shaped cross section is formed on the outer periphery of the shaft portion 3.
A convex portion 15 having a tapered cross section is provided on the valve seat 7, and the convex portion 15 is fitted into the concave portion 14.

By adopting such a configuration, the valve seat 7 is pushed up by the pressure of the fluid, and the pressure at the lower contact part between the valve seat 7 and the shaft 3 is lowered by the fluid, but the pressure at the upper contact part increases and a complete sealing effect is achieved. is obtained.

Particularly in the case of this embodiment, since the tip of the convex portion 15 is thin, it can be operated even when the fluid pressure is low.

In addition, FIG. 5 shows a configuration in which the outer periphery of the shaft portion 3 is formed with four portions having a U-shaped cross section, and the valve seat 7 is formed with a convex portion that fits into the recessed portion.
Due to the elasticity of the valve seat, the contact pressure can be increased, and the sealing effect can also be improved by the fluid pressure.

Effects of the invention Since the invention adopts the above-mentioned approach, the valve seat, The valve box and valve plate can be assembled or disassembled, and at the same time, the valve seat is tightened and fixed with a slight bulge on the inner circumferential side through the tapered shape, improving the sealing effect.

Furthermore, by simply fitting the valve plate shaft and valve seat through the recess or protrusion, the elasticity and fluid pressure of the valve seat allow for close contact, making assembly easy and ensuring a reliable sealing effect. It has practical effects such as easy disassembly and cleaning.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing an embodiment of the butterfly valve according to the present invention, Figures 2 A and B are side views of the shaft used in the present invention, and Figures 3 A and B are the valves used in the present invention. 4A and 5 are sectional views showing other embodiments, and FIG. 6 is a sectional view showing the shaft portion of a conventional butterfly valve. 3...Shaft part, 4.12.15...Convex part, 7...Valve seat, 11, 13.14...
Four parts.

Claims (1)

[Scope of utility model registration request] An annular valve seat made of rubber, synthetic resin, or other elastic material is inserted through the shaft of the valve plate that opens and closes the fluid passage, and is formed into a tapered shape so that it is thinner near the fluid passage. The valve seat is split into two at the outer peripheral edge, tapered so that the outer peripheral side is thinner, and has an annular valve box inserted through the shaft of the valve plate, and an annular tightening flange at the opposing inner end. a fluid passage pipe, a taper portion provided on the inner surface of the tightening flange portion to correspond to the tapered shape of the valve seat and the valve box, and a non-gang-shaped protrusion provided on a portion of the outer peripheral surface of the shaft portion. 1. A butterfly valve comprising: a ring-shaped protrusion or recess; and a recess or protrusion provided on the valve seat at a position corresponding to the ring-shaped protrusion or recess.