JPH0814407A - Butterfly valve - Google Patents

Abstract

PURPOSE:To prevent play on the like of the valve body of a butterfly valve and preclude risk of generation of turbulence etc., in a fluid by forming a ridge swelling in the direction across the plate thickness on a rotary shaft stretching in the shorter axis direction of the valve body, and fitting the rotary shaft in a shaft mounting hole which is provided as penetrating the center of the ridge in such a way as incapable of relative rotation. CONSTITUTION:A butterfly valve is for use in an exhaust shutter for the exhaust brake of a car, and the valve body 2 is made in elliptical plate, and ridges 3 having an approx. rectangular longitudinal section in the longer axis direction of the valve body 2 are provided on the front and rear sides of the axis L of a rotary shaft in the shorter axis direction. A shaft mounting hole 4 having a long elliptical hole is provided at the center axis of the ridge 3 over the whole length of the ridge, and the rotary shaft 5 is fitted in this hole. The rotary shaft 5 has a fit part 6 which is formed by notching the upper and lower surfaces approx. two thirds in the axial direction and has a section such as to be fitted tightly in the shaft mounting hole 4. This enables installation of a valve body 2 free from generation of play.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butterfly valve used as an exhaust shutter in an exhaust brake of an automobile, for example.

[0002]

2. Description of the Related Art Conventionally, as a butterfly valve used as an exhaust shutter of an exhaust brake of an automobile, those shown in FIGS. 6 and 7 are known.

In a butterfly valve (01) shown in FIG. 6, (02) is an elliptical plate-shaped valve element, and the valve element is provided at both outer peripheral edges of the axis of rotation 180 ° opposite to each other in the minor axis direction.
Raised ridges (03) bulging in the thickness direction of (02) are symmetrically formed over the required length. The central axis of the ridges (03) (03) is aligned with the center of thickness of the valve body (02).

A shaft mounting hole (04) is provided at the center of the raised strips (03) (03).
(04) are provided so that their axes are aligned with each other. The inner end portions of the pair of left and right rotating shafts (05) (06) are press-fitted into the shaft mounting holes (04) (04).

The butterfly valve (01 ') shown in FIG. 7 has a rectangular notch (07) (07) cut at both outer peripheral lines in the minor axis direction of an elliptical valve body (02) for rotation. By engaging the forks (010) and (010) attached to the inner ends of the shafts (08) and (09) with the notches (07) and (07), the valve body (02) and the rotating shaft (08 ) (09) is integrally combined.

The two butterfly valves (01) and (01 ') have respective valve bodies (2) in the conduit of the valve holder (not shown).
(2) is rotatably supported by supporting the rotating shafts (05), (06) and (08) (09) orthogonal to the pipe.

One shaft (06) (09) protruding through the wall surface of the valve holder to the outside is engaged with the handle (01)
By rotating the valve body (1) (not shown in FIG. 7), the valve bodies (2) and (2) are rotated to the open / close position in the conduit.

[0008]

In the former butterfly valve (01), when the valve body (02) is exposed to a high temperature fluid in the pipeline, thermal expansion of the valve body (02) causes shaft mounting. The inner diameter of the holes (04) (04) has been expanded, and the shaft mounting hole (04) and rotary shaft (0
5) Looseness or looseness may occur between (06).

On the other hand, in the latter butterfly valve (01 '), when a load is repeatedly applied to the valve body (02) due to a sudden change in fluid pressure, the fork (010) is deformed to open the mouth and There is a risk of looseness between the 010) and the valve body (02).

Further, since a large step is formed at the fitting portion between the valve body (02) and the fork (010), when the valve body (02) is opened, the fluid passing through the valve body (02) is exposed. There are problems such as turbulence and large flow resistance.

The above-mentioned conventional butterfly valve (01) (0
In each of 1 '), since the valve body (02) is supported by two rotary shafts, misalignment is likely to occur, and in order to accurately align the axes of the rotary shafts, the shaft mounting holes (04 ) And the notch (07) must be machined with high precision, and the work is complicated and the cost is high. Further, it takes a little time to assemble the valve body and the rotary shaft.

The present invention has been made to solve the above-mentioned problems. By supporting the valve body by penetrating it into the rotary shaft, rattling and misalignment of the rotary shaft can be prevented, and turbulent flow in the fluid, etc. It is an object of the present invention to provide a butterfly valve which prevents the occurrence of the above-mentioned phenomenon and can easily assemble the valve body and the rotary shaft.

[0013]

According to the present invention, the above problems can be solved as follows. (1) In a butterfly valve in which an elliptical plate-shaped valve body housed in a fluid flow passage is rotatably supported by a rotary shaft that is orthogonal to the fluid passage to open and close the fluid passage. A ridge that bulges in the plate thickness direction is formed on the axis of rotation of the valve body in the short axis direction, and a shaft mounting hole that matches the center of the valve body in the thickness direction is provided at the center of the ridge. In addition, the valve body and the rotary shaft are integrally connected by penetrating the rotary shaft so that one rotary shaft cannot rotate relative to the rotary shaft.

(2) In the above item (1), the cross section of the fitting portion between the shaft mounting hole and the rotary shaft is non-circular.

(3) In the above item (1) or (2), the cross-sectional shape of the valve element along the longitudinal axis is defined as a streamlined shape in which the thickness of the valve element gradually becomes thinner toward the outer peripheral end. To do.

[0016]

Since the rotary shaft is supported by the rotary shaft by penetrating one rotary shaft in the shaft mounting hole of the valve body so that the rotary shaft cannot rotate relative to the rotary shaft, backlash and misalignment do not occur in the rotary shaft. (Invention according to claim 1).

If the cross-sectional shape of the shaft mounting hole and the fitting portion of the rotary shaft is non-circular, even if the fitting portion of the rotary shaft is loosened, the rotation of the rotary shaft ensures the rotation of the valve element. (The invention according to claim 2).

By making the cross section of the valve body streamlined,
When the valve body is in the open position, the fluid smoothly flows along both sides of the valve body, so that turbulent flow does not occur and the flow resistance is significantly small (the invention according to claim 3).

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

The valve body (2) is in the shape of an elliptical plate, and on the rotational axis (L) in the minor axis direction, a ridge whose longitudinal cross-section in the major axis direction of the valve body (2) is substantially rectangular. Article (3) is provided on both sides.

A shaft mounting hole (4) having an elliptical cross section is formed in the central axis of the ridge (3) over the entire length of the ridge (3).

Reference numeral (5) is a rotary shaft, and the upper and lower surfaces are notched along the axial direction by about 2/3 thereof along the region corresponding to the length of the ridge (3), whereby the shaft mounting hole is formed. A fitting portion (6) having a cross-sectional shape capable of tightly fitting with (4) is formed.

A screw rod (7) for attaching an operating handle (not shown) is projected from one end of the rotary shaft (5), and a small-diameter support rod (9) described later is projected from the other end as well. It is set up.

FIG. 2 is a butterfly valve (1) shown in FIG.
FIG. 8 is a vertical cross-sectional front view showing a state in which is assembled into the pipe passage (8a) of the pipe body (8).

In the bearing portion (8b) facing the tube body (8) and facing outward, shaft holes (10) and (10) having the same diameter are coaxially formed. A cylindrical bearing (11) is fitted in each of the (10). An annular ring (12) is fitted onto the small-diameter support rod (9), and the support rod (9) is supported by a right bearing (11) via the ring (12). A circular base end portion (5a) of the rotary shaft (5) is supported by a left bearing (11).

Reference numeral (13) is a plurality of annular seal rings, and reference numeral (14) is a disk-shaped lid member that closes the open end of the right bearing (8a).

Next, the procedure for mounting the valve body (2) on the rotary shaft (5) will be described. After accommodating the valve body (2) in the pipe line (8a), the tip of the rotary shaft (5) is moved to the left bearing (11) in FIG.
Then, the fitting portion (6) is fitted into the shaft mounting hole (4).

Then, by inserting the support rod (9) into the ring (12) which has been fitted in the shaft hole (10) on the right side in advance, the valve body (2) and the rotary shaft are rotated. The valve body (2) is rotatably supported in the conduit (8a) while being integrally coupled with (5). After that, the shaft hole (10) on the right side by the lid material (14)
To block.

Thus, by rotating the handle screwed to the screw rod (7), the valve body (2) can be rotated to the open / close position in the pipe line (8).

As described above, the valve body (2) is attached to one rotary shaft.
As it is supported by (5), the rotating shaft can be
The axis of (5) is not displaced with respect to the valve body (2), and there is no risk of adversely affecting the rotation of the valve body (2).

Further, at the time of assembling or replacing the valve body (2), the removal and mounting of the rotary shaft (5) are simplified as compared with the conventional ones, so that the work is simplified.

Further, since the fitting portion (6) of the rotating shaft (5) is made non-circular, it is affected by exhaust heat and the valve body (2) is thermally expanded even when the rotating shaft (5) rotates. The valve body (2) will follow the
The function of the butterfly valve (1) is not impaired.

Next, a second embodiment of the present invention will be described with reference to FIG. The same members as those described in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In this embodiment, a plurality of key grooves (15) facing the axial direction are provided in the shaft mounting hole (4) of the raised ridge (3), and the key groove (15) is provided in the rotary shaft (5). By forming the keys (16) respectively, splines or serrations are fitted. By doing this, the valve body (2) and the rotating shaft
Even if some gap is generated due to thermal expansion between (5),
The rotation of the rotating shaft (5) is reliably transmitted to the valve body (2).

Even in the second embodiment, the valve body of the rotary shaft (5)
The attachment to (2) may be performed by the same method as described in the first embodiment. In addition, in the second embodiment as well, the first
The same operation and effect as those of the embodiment are obtained.

Next, a third embodiment of the present invention shown in FIGS. 4 and 5 will be described. The same members as those described in the first and second embodiments will be designated by the same reference numerals, and the description thereof will be omitted. Valve body (2 ') shown in the third embodiment
Is characterized in that the cross-sectional shape along the axial line of the major axis is streamlined so that the plate thickness gradually becomes thinner as it goes to the outer peripheral edge.

In this way, when the valve body (2) is opened in the conduit (8), the fluid smoothly flows along the gentle curved surfaces on both sides of the valve body (2), so that turbulent flow is prevented. There is no possibility of generating it, and the flow resistance becomes small.

Also in the third embodiment, the same actions and effects as those shown in the first and second embodiments can be obtained. The shape of the non-circular hole is not limited to this embodiment.

When the present invention is applied to control a fluid having a relatively low temperature, the rotary shaft (5) and the shaft mounting hole (4) are not made non-circular, but the shaft mounting hole having a circular cross section is used. In addition, there is a case where the connecting structure is simply formed by press-fitting a round rod-shaped rotating shaft.

[0040]

The present invention can bring the following effects. (a) By using a single rotating shaft and penetrating the valve,
There is no misalignment of the rotating shaft and the rotating shaft does not come off from the valve body.

(B) Since the rotary shaft is an integral part, it is easy to remove and install the rotary shaft when assembling or replacing the valve body.

(C) Since the cross-sectional shape of the fitting portion between the shaft mounting hole and the rotary shaft is non-circular, even if the fitting portion is loosened, the rotation of the rotary shaft is reliably transmitted to the valve body. (Claim 2).

(D) By making the cross section of the valve disc streamlined, when the valve disc is opened, the fluid flows smoothly on both sides of the valve disc without causing turbulent flow. Therefore, the distribution resistance is small (claim 3).

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a valve body and a rotating shaft according to a first embodiment of the present invention.

FIG. 2 is likewise a vertical sectional front view of a tubular body to which the present invention is applied.

FIG. 3 is an exploded perspective view showing a second embodiment of the present invention.

FIG. 4 is a perspective view of a valve body showing a third embodiment of the present invention.

5 is a vertical cross-sectional view taken along the line VV of FIG.

FIG. 6 is an exploded perspective view of a valve body and a rotating shaft in a conventional butterfly valve.

FIG. 7 is an exploded perspective view of a valve body and a rotary shaft of another conventional example.

[Explanation of symbols]

 (1) Butterfly valve (2) (2 ') Valve body (3) Raised ridge (4) Shaft mounting hole (5) Rotating shaft (6) Fitting part (7) Screw rod (8) Pipe (8a) Pipe Channel (8b) Bearing part (9) Support rod (10) Shaft hole (11) Bearing (12) Ring (13) Seal ring (14) Cover material (15) Keyway (16) Key

Claims (3)

[Claims] 1. A butterfly valve in which an elliptical plate-shaped valve element housed in a fluid passage is rotatably supported by a rotary shaft that is orthogonal to the passage to open and close the passage. A ridge that bulges in the plate thickness direction is formed on the axis of rotation of the valve body in the minor axis direction, and a shaft mounting hole that aligns with the center of the valve body in the thickness direction is formed at the center of the ridge. A butterfly valve characterized in that the valve body and the rotary shaft are integrally connected by penetrating and penetrating one rotary shaft in the shaft mounting hole so as not to rotate relative to each other. 2. The butterfly valve according to claim 1, wherein a cross-sectional shape of a fitting portion between the shaft mounting hole and the rotary shaft is non-circular. 3. The valve body according to claim 1 or 2, wherein the cross-sectional shape of the valve body along the longitudinal axis is a streamline whose thickness gradually decreases as the plate thickness of the valve body approaches the outer peripheral end. Butterfly valve.