JP2000193128A - Actuator for valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep a valve in an opened state even though a motor is not in a normal energization state, automatically close the valve in the service interruption and the like, and prevent an unexpected accident by using an opening and closing display board displaying the opening and the closing state of the valve, as an output shaft locking member. SOLUTION: When a motor 3 is driven in the closing of a valve V, an output shaft 2 is rotated through the deceleration gears 31, 32, a valve element starts its opening, and simultaneously a power spring 4 starts its winding-up. When the deceleration gear 32 is rotated by 90 deg. and contacted with a stopper, its rotation is stopped and the valve V is fully opened. When the energization to the motor 3 is cut in this state, the valve V is completely closed by the restoring force of the power spring 4 through the output shaft 2. On this occasion, the valve V is locked in an opened state through an opening and closing display board 5, when the opening and closing display board 5 is pressed against a spring 6 in the full-opened state of the valve V, and the projections 52, 52 are fitted in the recessed parts 11, 11 of a casing 1 to cut the power supply to the motor 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring for winding a spring when an output shaft is rotated by driving a motor to open a valve, and a restoring force of the spring when power to the motor is cut off. The present invention relates to a valve actuator in which an output shaft is rotated in a valve closing direction to open and close a valve.

[0002]

2. Description of the Related Art Conventionally, an output shaft for driving a valve and a motor for rotating the output shaft in a direction in which the valve is opened are provided in a casing, and the motor is wound when the valve is opened to store a restoring force. There has been a simple valve actuator that does not use a clutch provided with a mainspring.

[0003]

In this type of conventional simple valve actuator, when the valve is opened, the driving force of the motor is used, and when the valve is closed, the restoring force of the mainspring is used. However, in order to keep the valve open, that is, to keep the output shaft locked, the excitation coil of the motor must be constantly energized.

The motor used in this type of valve actuator is an impedance type motor in which the exciting coil does not burn out even when the rotor is stopped and the power is supplied. There is no problem as long as the electric system is operating normally.However, if an accident such as a power failure occurs when the valve must be kept open, Since the lock is released and the valve automatically closes, an unexpected accident may occur.Also, it is necessary to keep the excitation coil energized while the valve is kept open. There is a problem that unnecessary power is consumed.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art by manually locking the output shaft when the valve is kept open to prevent an electric system accident such as a power failure. It is another object of the present invention to provide a safe and economical valve actuator.

[0006]

An actuator for a valve according to the present invention is provided with an output shaft for driving the valve in a casing and a motor for rotating the output shaft in a direction in which the valve is opened. In a valve actuator provided with a mainspring that is wound at the time of the opening operation and stores a restoring force, a valve opening / closing display plate that can slide along an output shaft via a spring at an end of the output shaft protruding from a casing via a spring. A projection is formed on the surface of the opening / closing display panel facing the casing, and a recess having a diameter slightly larger than the diameter of the projection fitted with the projection is formed in a part of the casing to open the valve. Sometimes, the open / close display plate is pushed toward the casing so that the protrusion of the open / close display plate is fitted into the recess of the casing so as to prevent the output shaft from rotating in the valve closing direction. It is characterized in.

[0007]

The projection of the open / close display plate is engaged with the side wall of the concave portion of the casing to prevent the output shaft from rotating in the valve closing direction.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the actuator of the present invention will be specifically described with reference to the drawings. 1 is a plan view of the actuator of the present invention, FIG. 2 is a vertical sectional side view taken along the line AA of FIG. 1, FIG. 3 is a vertical sectional side view of the output shaft locked state, and FIG. It is a schematic plan view showing a drive mechanism.

1 is a casing, 2 is a casing 1
An output shaft connected to the rotation shaft of the valve body of the valve V;
Are motors for rotating the output shaft 2 in a fixed direction via reduction gears 31 and 32 to open the valve A;
Is wound by rotation of the motor 3 in the valve opening direction,
A spring is wound around the output shaft 2 for closing the valve A by rotating the output shaft 2 in reverse by the restoring force, and these members constitute an actuator.

The reduction gear 32 fixed to the output shaft 2 is shown in FIG.
The stoppers 3a and 3b are fixed to a part of the casing 1 so as to be rotatable within a range of 90 degrees.

Reference numeral 5 denotes an open / close display plate into which a central hole 51 is fitted so as to be slidable up and down via a spring 6 from an upper end of the output shaft 2 projecting upward from the casing 1. The upper end of the output shaft 2 is stopped by a retainer so as not to fall off, and a protective cap 51 is integrally covered with the upper end of the output shaft 2 so as not to hurt the hand when pressed down by hand.

A downward projection 5 is provided on the lower surface of the open / close display panel 5.
When the open / close display panel 5 is pressed down against the spring 6, the lower ends of the projections 52, 52 are formed in the thick portion of the upper surface of the casing 1.
1 and 11 are fitted.

The recesses 11, 11 are formed to have diameters slightly larger than the diameters of the projections 52, 52 of the open / close display panel 5, and the centers of the projections 52, 52 when the valve V is fully opened and the recesses 11, 11 thereof. Are formed at positions where the centers of the.

Next, the operation of the actuator of the present invention will be described with reference to the illustrated embodiment in accordance with the above-described structure of the present invention.

In the closed state of the valve V shown in FIG.
When the motor 3 is energized to drive the motor 3, the reduction gear 3
At the same time as the output shaft 2 is rotated via 1 and 32 to open the valve body of the valve V, the mainspring 4 starts to wind.

When the reduction gear 32 rotates by 90 degrees, it comes into contact with the stopper -3a to stop the rotation, and the valve V is fully opened.

At this time, since the motor 3 is still energized, this fully open state is maintained.

In this state, when the power supply to the motor 3 is cut off, the lock by the motor is released, and the output shaft 2 is driven by the restoring force of the accumulated spring 4 so that the reduction gear 32 is moved to the stopper-3.
The valve V rotates backward until it comes into contact with the position b, and the valve V closes.

The above operation is repeated each time the energization and cutoff of the motor 3 is repeated. When the valve V is fully opened, the open / close display plate 5 is spring-loaded when the motor 3 is energized. 6 against the restoring force, the projections 52, 52 are fitted into the recesses 11, 11 of the casing 1, and when the power supply to the motor 3 is cut off in this state, the output shaft 2 closes the valve. , The open / close display plate 5 also rotates integrally, and the projection 52,
52 engages with the side walls of the recesses 11, 11 of the casing 1 to stop the rotation of the output shaft 2.

Since the contact force of the projection 52 against the side wall of the concave portion is extremely large and the frictional resistance is much larger than the restoring force of the spring 6, the projections 52, 52 cannot come off from the concave portions 11, 11, and This rotation stop state is maintained even when the hand is released, and the valve is locked in the valve open state in FIG.

When the motor 3 is energized again in the locked state with the valve open, the output shaft 2 rotates in the valve opening direction, and the open / close display plate 5 returns to the fully open position of the valve and the projections 53, 52. The frictional engagement between the opening and the side wall of the recess is released, so that the opening / closing display plate 5 or the spring 6 returns to the original position by the restoring force, and the projections 53 and 52 come off the recesses 11 and 11.

When the energization of the motor 3 is stopped in this state, the lock by the motor is released and the valve V is closed as described above.

[0023]

According to the actuator for a valve according to the present invention, a valve actuator which utilizes the driving force of a motor when opening a valve and utilizes the restoring force of a mainspring when closing a valve. Since the open / close display plate for indicating that the valve is open or closed is used as a lock member for the output shaft, the valve can be kept open even if the motor is not constantly energized. This prevents accidental accidents such as power failure due to the valve automatically closing even if an accident such as a power failure occurs. Also, while the valve is open, power is supplied to the motor. It is not necessary to consume unnecessary power, and it is economical and energy saving.
It is useful for.

In this embodiment, the open / close display plate is a disk-shaped display plate. However, a lever-handle display plate may be used so that the valve can be manually opened in the event of a power failure. is there.

[Brief description of the drawings]

FIG. 1 is a plan view of an actuator according to the present invention.

FIG. 2 is a longitudinal sectional side view taken along line AA of FIG.

FIG. 3 is a vertical sectional side view of the output shaft in a locked state.

FIG. 4 is a schematic plan view illustrating a driving mechanism of an output shaft.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 casing 11 concave portion 2 output shaft 3 motor 31 reduction gear 32 reduction gear 4 mainspring 5 open / close display plate 52 projection 6 spring

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H062 BB04 BB33 CC01 CC29 DD11 FF05 FF10 FF30 3H063 BB43 BB50 DA14 DB39 DB50 EE12 3H065 BA01 BB02 BC03

Claims (1)

[Claims] An output shaft for driving a valve and a motor for rotating the output shaft in a direction in which the valve is opened are provided in a casing, and a spring for winding the valve when the valve is opened and storing a restoring force is provided. In the valve actuator, an open / close display plate of a valve slidable along the output shaft via a spring is provided at an end of the output shaft protruding from the casing, and the open / close display plate is provided on a surface side facing the casing. A projection is formed, and a recess having a diameter slightly larger than the diameter of the projection to which the projection is fitted is formed in a part of the casing. Characterized by being fitted in the recess of the casing to prevent the output shaft from rotating in the valve closing direction.