JP2001082614A - Butterfly valve for actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent large burden from applying on a motor of an actuator by molding a part where abuts on a valve element of a seal ring of a butterfly valve with a recoverable material that is an elastically deformed. SOLUTION: A rotary shaft of a valve element 3 is connected to an output shaft of an actuator, the valve element 3 is rotated by driving a motor in the actuator, and thereby, a valve is opened/closed. A hollow part 21 of a seal ring 2 is formed on a part where abuts on the valve element 3, or the seal ring 2 is molded by covering a foaming material 22 such as urethane with a recoverable material 23 that is elastically deformed like a rubber. The valve element 3 is rotated to a closing position, an outer periphery of the seal ring 2 is pushed by the valve element 3 so as to deform the hollow part 21 of the seal ring 2. Furthermore, the valve element 3 is rotated, the hollow part 21 is deformed, and thereby, a fluid is completely sealed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butterfly valve for an actuator which opens and closes a valve body by an actuator which opens and closes a valve by rotating an output shaft by driving a motor.

[0002]

2. Description of the Related Art Conventionally, there has been a butterfly valve as an inexpensive valve for controlling a large flow rate of a fluid.

[0003]

In a conventional butterfly valve of this type, a seal ring a for preventing fluid leakage at a closed position of a valve body has a portion a 'where a valve body abuts as shown in FIG. The whole, including the rubber, was formed of an elastic material such as rubber.

When controlling the opening and closing of the butterfly valve by manual operation, it is easy to adjust the degree of closing of the valve body irrespective of the hardness of the seal ring, so there is no problem. When controlling the opening and closing of a butterfly valve using an actuator that opens and closes the valve by rotating the shaft, the valve body contacts the seal ring in order to securely close the valve body against the hardness of the seal ring. Each time a large torque is applied to the motor at a location and the valve is closed, the load on the motor increases, and the life of the motor is shortened. I couldn't do that.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a butterfly valve which can use an actuator which opens and closes a valve by rotating an output shaft by driving a motor.

[0006]

A butterfly valve according to the present invention is characterized in that at least a portion of a seal ring of the butterfly valve which comes into contact with a valve body is formed of a resilient material which is elastically deformed.

[0007]

When the valve body comes into contact with the seal ring, a part of the seal ring is deformed without putting a large load on the motor, and the fluid is completely sealed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the butterfly valve of the present invention will be specifically described with reference to the drawings. FIG. 1 is a perspective view showing a state in which an actuator is attached to the butterfly valve of the present invention, FIG. 2 is an enlarged sectional view of a main part showing a relationship between a valve body and a seal ring, and FIG. FIG. 4 is an enlarged sectional view of a main part showing a rotated state, and FIG. 4 is an enlarged cross-sectional view of a main part showing a relationship between a valve body and a seal ring of another embodiment.

1 is a butterfly valve main body, 2 is a seal ring, and 3 is a valve body. The rotation shaft of the valve body 3 is connected to the output shaft of the actuator 4 and the valve is driven by the motor in the actuator 4. The body 3 is rotated to open and close the valve.

2 and 3, the seal ring 2 is made of the same material as the seal ring of the conventional butterfly valve, and a hollow portion 21 is formed at a portion where the valve body 3 comes into contact. The seal ring 2 is formed by covering a foaming elastic material 22 such as urethane with an elastically deformable restorable material 23 such as rubber.

2 and 3, when the valve element 3 is rotated to the closed position, the hollow portion 21 of the seal ring 2 is deformed as shown in FIG. When rotates, the hollow portion 21 is deformed as shown in FIG. 3 to completely seal the fluid.

In FIG. 4, when the valve body 3 is rotated to the closed position, the foamed elastic material 22 of the seal ring 2 is pressed by the outer periphery of the valve body 3 and deforms with a small force to completely seal the fluid. I do.

[0013]

According to the butterfly valve for an actuator according to the present invention, at least a portion of the seal ring of the butterfly valve that comes into contact with the valve body is formed of a resilient material that elastically deforms, and a portion of the seal ring where the valve body contacts Since the valve is softened, even if the valve body is rotated to the fluid sealing position, a large load is not applied to the actuator motor, and the opening and closing of the butterfly valve can be controlled by the actuator. Thus, an inexpensive butterfly valve can be used as an electric valve even if it is not an expensive valve such as a ball valve, so that the cost of the flow control of automatic management can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state where an actuator is attached to a butterfly valve of the present invention.

FIG. 2 is an enlarged sectional view of a main part showing a relationship between a valve body and a seal ring.

FIG. 3 is an enlarged sectional view of a main part showing a state in which the valve body has rotated from the state of FIG. 2;

FIG. 4 is an enlarged sectional view of a main part showing a relationship between a valve body and a seal ring of another embodiment.

FIG. 5 is an enlarged sectional view of a main part showing a relationship between a valve body and a seal ring of a conventional butterfly valve.

[Explanation of symbols]

 1 Butterfly valve body 2 Seal ring 3 Valve body 4 Actuator

Claims (3)

[Claims] 1. A butterfly valve for an actuator, wherein at least a portion of a seal ring of the butterfly valve which comes into contact with a valve body is formed of a resilient material that elastically deforms. 2. The butterfly valve for an actuator according to claim 1, wherein at least a portion of the seal ring in contact with the valve body is hollow. 3. A butterfly valve for an actuator according to claim 1, wherein said seal ring is formed of a composite material of a foamed elastic material such as urethane and a resilient material which is elastically deformable such as rubber.