JPS643027Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a butterfly valve for regulating the flow rate of fluid.

Prior Art When a butterfly valve opens and closes the valve body using a handle fitted to the valve stem, in order to fix the valve body at a constant opening degree, a scale plate for setting the opening degree of the valve body is attached to the valve stem under the handle. A lever that moves together with the handle is fitted and fixed in a recess around the scale plate.

Problems with the prior art However, this scale plate is simply overlapped with the flange of the valve body and fixed with bolts and nuts. When an external force is applied, such as when the bolts collide with each other, the bolt holes in the scale plate become elongated holes, which not only makes it impossible to set the opening accurately, but also sometimes prevents the valve from being fully closed.

Purpose of this invention This invention solves the above-mentioned drawbacks by fitting the scale plate and the valve case in a concave-convex manner, so that the scale plate is securely fixed to the valve case and the direction of the handle can be changed by 180 degrees. It is intended to provide a butterfly valve.

Structure of this invention Next, the butterfly valve of this invention will be explained with reference to the drawings.

In the figure, 1 is a valve box, 2 is a valve body, 3 is a valve stem,
4 is a valve seat, 5 and 6 are bushes, 7 is a handle, the valve body 2 is installed in the valve body 1 via the valve seat 4, and the valve stem 3 passes through the valve body 2 and the valve seat seat 4. is inserted into the valve body 1 via the bushes 5 and 6, and by rotating the handle 7 fixed to the valve stem 3, the valve body 2
is capable of opening and closing a fluid passage within the valve box 1, thereby forming a butterfly valve.

In the present invention, a scale plate 8 for setting the opening degree of the valve body 2 is superimposed on the flange 11 of the valve body 1, and the flange surface and the scale plate are fitted with convexes and convexes and are fixed with bolts and nuts 9.

The uneven fitting between the flange surface and the scale plate is the scale plate 8.
A pair of convex portions 8 symmetrical to the central axis of the valve stem 3 is provided on the back surface of the valve stem 3.
1 and 81 are formed, and the concave portions 12 and 1 fit into the convex portions 81 and 81 of the scale plate 8 on the flange 11 of the valve body 1.
2 are formed, and these convex portions 81 and concave portions 12
The two are fitted together to determine their position.

The convex portions 81, 81 of the scale plate 8 may be formed as concave portions, and the concave portions 12 of the flange 11 may be formed as convex portions. In addition, the convex portions and the concave portions may be provided in a plurality of pairs, so long as they form a pair corresponding to the central axis.
The shape of the valve rod 3 may be any shape that can be fitted and positioned.
It is preferable that the convex and concave portions are arc-shaped with a constant radius centered on the axis of the shaft, since this has high strength and is not prone to breakage.

Further, a gear-shaped unevenness 82 is provided around the scale plate 8, and the pawl 72 of the lever 71 of the handle 7 engages with this unevenness 82, so that the position of the handle 7 can be determined. Of course, the handle 7 is provided with a pointer 73, and the unevenness 82 of the scale plate 8 and the pawl 72 of the lever 71 are adjusted so that the opening degree scale 83 of the scale plate 8 pointed by this pointer matches the opening degree of the valve body 2. is formed.

To open or close the valve, grasp the lever 71 of the handle 7, release the pawl 72 of the lever 71 from the unevenness 82 of the scale plate 8, rotate the handle, and release the lever 71 at the required opening position. Tetsume 72
By engaging with the unevenness 82, a constant opening degree can be set.

Effects of this invention The butterfly valve of this invention is constructed as described above, and the scale plate is provided with a pair of protrusions or recesses that are symmetrical about the central axis on the flange of the valve box. Since it is fixed by fitting into a concave or convex part, even if an external force is applied to the handle, it will be received by the concave-convex fit, and the bolt hole of the scale plate will not transform into a long hole, and the opening degree will be maintained accurately. can do.

In addition, the protrusions and recesses are arranged in symmetrical pairs around the central axis, so if the direction in which the handle protrudes gets in the way, the scale plate can be rotated 180 degrees to change the direction of the handle. The direction of the handle can be changed more easily than when changing the entire mounting direction.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of the butterfly valve of this invention, Fig. 2 is a bottom view of Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 1, and Fig. 4 is a bottom view of the scale plate. It is. 1... Valve box, 11... Flange, 12... Recess, 2... Valve body, 3... Valve stem, 4... Valve seat, 7...
...Handle, 71...Lever, 72...Claw, 8
... Scale plate, 81 ... Convex portion, 82 ... Gear-shaped unevenness.

Claims (1)

[Scope of utility model registration request] A scale plate for setting the opening degree of the valve body is overlapped with a flange of the valve body coaxial with the valve stem, and a pair of convex portions or concave portions symmetrical to the central axis of the valve stem is formed on the back surface of the scale plate. A butterfly valve characterized in that a flange of the box is provided with a pair of concave portions or convex portions that fit with a pair of convex portions or concave portions of the scale plate, and these are fixed by fitting into the concave and convex portions.