JP2561624Y2 - Butterfly valve - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a butterfly valve.

[0002]

2. Description of the Related Art As shown in FIG. 5, in a butterfly valve in which a plurality of valve bodies 22 are attached to a single shaft 21 and the plurality of valve bodies 22 are simultaneously opened and closed, a seating surface provided on the shaft 21 is provided. Since there is a variation in the angle, the mounting of the valve element 22, and the position of the port 23, the fully closed angles differ between the valve elements 22 and a difference in the leak flow rate between the ports 23 when the ports are fully closed. This is because the valve body 22 is fixed to the shaft 21 so that even if one of the plurality of valve bodies 22 is fully closed, the rotation of the shaft 21 at that position does not occur even if the other valve bodies 22 are not fully closed. It is caused by stopping. In order to avoid this at the mounting portion of the valve body 22, conventionally, as shown in FIG. 6, the valve body 22 is divided into an inner peripheral side divided body 24 and an outer peripheral side divided body 2 as shown in FIG.
5, and the two divided bodies 24 and 25 are connected via an elastic body 26. In this prior art, the valve body 22 composed of the two divided bodies 24 and 25 and the elastic body 26 is used. There is a problem that it takes a great deal of time to manufacture.
Therefore, conventionally, as shown in FIG. 7, a butterfly valve has been developed so that all of the plurality of valve elements 22 can be completely closed while the valve element 22 is a single rigid plate. .

[0003]

However, the prior art shown in FIG. 7 has a recess 27 provided on the peripheral surface of the shaft 21.
Since the depth of the screw hole 28 provided in the remaining portion of the shaft 21 is short, a thicker shaft can be used or the valve body 22 can be offset from the center of the shaft 21. Otherwise, there is a problem that a sufficient tightening allowance for the fixing screw 29 cannot be secured. The depth of the recess 27 is a / 2 + b, where a is the diameter of the shaft 21, b is the thickness of the valve body 22, c is the thickness of the flange 32 on the bearing surface 31 side of the elastic body 30 having a substantially U-shaped cross section. / 2 + c.

[0004]

SUMMARY OF THE INVENTION In view of the above, the present invention has been devised in order to solve the above-mentioned problems of the prior art. When the diameter of the shaft is a and the thickness of the valve body is b, a / 2 + b /
2, a recess having a depth of 2 and a bottom surface of the recess serving as a seat surface for supporting the valve body, and a screw hole opening on the shaft provided on the shaft, and screwed into the seat surface and the screw hole. A collar and a washer are interposed between the heads of the screws, an elastic body having a substantially L-shaped half section is interposed between the seat surface and the washer, and the valve is interposed between the seat surface and a flange portion of the elastic body. A butterfly valve is provided which has a relief recess of a predetermined angle in a portion of the seat surface which presses the valve body when the valve is closed.

[0005]

The valve body is sandwiched between the seat and the only flange of the elastic body without offset so as to be in contact with the seat surface. The depth of the concave portion provided on the peripheral surface of the shaft is a / a where a is the diameter of the shaft and b is the thickness of the valve body.
2 + b / 2, which is smaller by c (thickness of the flange portion) than the prior art shown in FIG. 7, so that the length of the screw hole can be increased by c. Also, since a relief recess having a predetermined angle is provided in a portion of the seat surface that presses the valve body when the valve is closed, even if the valve body is fully closed, the rotation of the shaft is continued to fully close other valve bodies. .

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

As shown in FIGS. 1 and 2, the diameter of the shaft 1 is a on the peripheral surface of the shaft 1 and the thickness of the valve body 2 is a / 2 + a.
A concave portion 3 having a depth of b / 2 is formed, and a bottom surface of the concave portion 3 is a seat surface 4 that contacts the valve body 2 and supports the valve body 2.
A screw hole 5 is formed in the shaft 1 so as to open in the seat surface 4, and a collar 8 and a washer 9 are sandwiched between the seat surface 4 and a head 7 of a fixing screw 6 screwed into the screw hole 5. . An elastic body 10 having a substantially L-shaped half section is sandwiched between the seat surface 4 and the washer 9 on the outer peripheral side of the collar 8. The material of the elastic body 10 is, for example, fluorine rubber. Seat 4 and flange 1 of elastic body 10
1, the valve body 2 is sandwiched between the elastic bodies 10 on the outer peripheral side thereof. The valve body 2 is a single rigid plate and is sandwiched in contact with the seat surface 4 without offset. A relief recess 12 having a predetermined angle θ is formed in a portion of the seat surface 4 that presses the valve body 2 when the valve is closed.

[0008] The butterfly valve having the above-described structure includes an elastic body 1
0 is substantially L-shaped in half-section, and the valve body 2 is sandwiched between the seat surface 4 and the only flange portion 11 of the elastic body 10 so as to be in contact with the seat surface 4 without offset. Since the depth of the concave portion 3 provided on the peripheral surface of the shaft 1 is set to a / 2 + b / 2 as described above, the depth is reduced by c (thickness of the flange portion) as compared with the prior art of FIG. Therefore, the length of the screw hole 5 can be increased by the length of c, and a large tightening allowance for the fixing screw 6 can be secured. Further, since the relief recess 12 is provided on the valve closing side of the seat surface 4, even if the valve element 2 is fully closed (FIG. 3), the rotation of the shaft 1 can be continued so as to fully close other valve elements. Yes (Figure 4).

[0009]

[Effects of the Invention] The present invention has the following effects. That is,
The half cross section of the elastic body is substantially L-shaped, and the valve body is sandwiched between the seat surface and the flange portion of the elastic body without offset so as to be in contact with the seat surface. Since the depth is made shallower than that of the prior art, the length of the screw hole can be made longer than that of the conventional art, and the tightening allowance of the fixing screw can be sufficiently secured. In addition, because a relief recess with a predetermined angle is provided in the part of the seat surface that presses the valve element when the valve is closed, even if the valve element is fully closed, the rotation of the shaft continues to fully close other valve elements Can be done.

[Brief description of the drawings]

FIG. 1 is a sectional view of a butterfly valve according to an embodiment of the present invention.

FIG. 2 is a sectional view of a shaft.

FIG. 3 is a sectional view showing an operating state of the butterfly valve.

FIG. 4 is a sectional view showing an operating state of the butterfly valve.

FIG. 5 is a structural explanatory view of a butterfly valve.

FIG. 6 is a sectional view of a butterfly valve according to a conventional example.

FIG. 7 is a sectional view of a butterfly valve according to another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 shaft 2 valve body 3 recessed part 4 seating surface 5 screw hole 6 fixing screw 7 head 8 collar 9 washer 10 elastic body 11 flange part 12 relief recess

Claims (1)

(57) [Scope of request for utility model registration] 1. A concave portion 3 having a depth of a / 2 + b / 2 where a diameter of the shaft 1 is a and a thickness of the valve body 2 is b is provided on a peripheral surface of the shaft 1, and a bottom surface of the concave portion 3 is formed by the valve. A bearing surface 4 for supporting the body 2, a screw hole 5 opening in the bearing surface 4 is provided in the shaft 1,
A collar 8 and a washer 9 are sandwiched between the seat surface 4 and a head 7 of a fixing screw 6 screwed into the screw hole 5, and a substantially L-shaped resilient half-section is provided between the seat surface 4 and the washer 9. The valve body 2 is sandwiched between the seat surface 4 and the flange portion 11 of the elastic body 10, and a predetermined portion of the seat surface 4 which presses the valve body 2 when the valve is closed. A butterfly valve having an angled recess 12.