JPH08170748A - Case of valve actuator - Google Patents

Abstract

PURPOSE: To reduce manufacturing cost and operation time, improve strength of connection and sealability by forming a case body, and base or cover of resin, forming a ribbed projection on one of them and an abutting surface on the other, melting the ribbed projection for integrating them. CONSTITUTION: A case body 2 and a base 3 are also made of synthetic resin, such as nylon, PBT, PPs. A lower portion of the case body 2 is opened, while the opened surface is blocked by the base 3. A ribbed projection 5 is formed on an abutting surface of the case 2, while extending over a circumference thereof. The ribbed projection 5 abuts against an abutting surface 6 of the base 3. The ribbed projection 5 is then melted for connection. This melting of the ribbed projection 5 may be performed by the use of frictional thermal melting due to oscillation deposit, and induction heating deposit. In the case of oscillation deposit, connection is completed in 10 to 15 seconds even including cooling time, thereby operation period is remarkably reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a case of a valve actuator for driving a valve body of various valves such as a butterfly valve.

[0002]

2. Description of the Related Art Conventionally, in order to rotationally drive valve bodies of various valves such as butterfly valves and ball valves, an actuator is connected to a valve rod extending outside the valve body, and the actuator is manually or automatically driven. This is well known.

The valve actuator is generally composed of a case main body incorporating a driving force transmitting means consisting of a gear train, and a cover or base covering the open surface of the case main body. The case main body and the cover or base are joined together. It has a box-shaped case.

The case is made of metal or resin, and the case body is joined to the cover or the base by fastening means such as bolts and rivets or joining means such as welding. For example, when fastening a resin case with bolts, if the tap hole is directly machined into the case, the screw groove may be damaged by the fastening force, so it is necessary to take measures such as burying metal in the resin to secure fastening strength. Become. Further, in order to obtain the hermeticity of the case, it is necessary to fasten at least three places with bolts, and the number of parts is large. Therefore, in the case of the conventional actuator, it is possible to avoid the cost increase due to the increase of the number of parts and the working time. I could not do it.

[0005]

SUMMARY OF THE INVENTION The present invention uses a fastening means such as bolts and rivets by molding a case main body and a cover or a base that form a case with resin, and joining them by melting the resin. Is not required, the number of parts is reduced, and sufficient sealing performance is ensured.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems, the means adopted by the present invention comprises a case of valve actuators joined to each other and a case body and a base or cover which can be joined to each other. , The case main body and the base or the cover are made of resin, and the rib-shaped projection is formed on either the case main body and the base or the cover, and the rib-shaped projection is formed on the other, and the rib-shaped projection is melted. Then, the case body and the base or the cover are integrally joined.

Further, it is characterized in that walls are provided upright on both sides of the abutting surface so that the molten burr of the rib-like projection is not exposed to the outside.

[0008]

[Operation] A rib-shaped projection is formed on one of the case main body and the base or the cover, and an abutting surface is formed on the other, and the rib-shaped projection is melted and joined to the abutting surface. By joining, the case main body and the base or cover are integrated to form a case.

Since walls are erected on both sides of the abutting surface so that the molten resin does not flow out, there is no possibility that burrs are generated outside.

[0010]

According to the present invention, the case body and the base or the cover can be integrally joined, and no parts such as bolts are required for joining, so that the cost and the working time can be reduced. In addition to being able to secure the joint, it is possible to obtain a case with high sealing performance.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the drawings. (1) shows a case of a valve actuator according to the present invention, which is composed of a case body (2) and a base (3) as well known in the art, and incorporates a power transmission means composed of a gear train in which a plurality of gears are combined. A space (4) is formed for this purpose.

Both the case body (2) and the base (3) are made of synthetic resin such as nylon, PBT or PPS. In the illustrated embodiment, the lower part of the case body (2) is opened,
Although the open surface is closed by the base (3), it is of course possible to open the upper surface of the case body (2) and close it by the cover. It should be understood as substantially the same.

The bases (3) are butted against each other along the entire circumference of the open surface of the case body (2), and the butted surfaces are partially melted and integrally joined.

As shown in FIG. 2, a rib-like protrusion (5) is formed on the abutting surface of the case body (2) so as to extend continuously over the entire circumference, and the rib-like protrusion (5) is used as a base (3). )
The rib-shaped projections (5) are melted and joined by abutting against the butting surface (6) of the. Vertical walls (7) and (8) are continuously erected on both sides of the abutting surface (6) of the base (3) over the entire circumference,
The rib-like protrusions (5) are joined so as to be positioned in the groove surrounded by the walls (7) and (8). Therefore, the molten burr (9) generated by the melting of the rib-shaped protrusions (5) is contained in the groove surrounded by the walls (7) and (8) as shown in FIG. 3 and is not exposed to the outside. The appearance is good, and post-processing such as deburring is unnecessary.

The rib-like protrusions (5) have a predetermined length with a melting margin. The melting margin is not particularly limited, but about 1.2 mm is suitable.

The rib-like protrusions (5) can be melted by means of frictional heat melting by vibration welding, induction superheat welding or the like. For example, in the case of using the vibration welding means, the joining can be achieved in about 10 to 15 seconds including the cooling time, and the working time can be remarkably shortened.

Of course, the rib-like projections (5) and the abutting surfaces (6) may be positioned opposite to those shown in the drawing.

[Brief description of drawings]

[Fig. 1] Vertical sectional view

FIG. 2 is a vertical cross-sectional view before joining

FIG. 3 is an enlarged sectional view of a joint portion.

[Explanation of symbols]

 (1) Case (2) Case body (3) Base (4) Space (5) Rib-shaped protrusion (6) Butt face (7) Wall (8) Wall (9) Bar

Claims (2)

[Claims] 1. A case of valve actuators joined to each other is constituted by a case body and a base or cover that can be joined together, and the case body and the base or cover are made of resin, and the case body and the base or cover are formed. A rib-shaped projection is formed on one of the two and a butting surface on which the rib-shaped projection is abutted is formed, and the rib-shaped projection is melted to integrally join the case body and the base or the cover. The case for the valve actuator. 2. The case according to claim 1, wherein walls are provided upright on both sides of the abutting surface so that the molten burrs of the rib-shaped projections are not exposed to the outside.