JP2006064169A - Actuator for valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator for a valve capable of preventing hunching by interposing a reverse input prevention clutch transmitting a rotating force from a motor to an output shaft side and not transmitting a rotating force from an output shaft side to a motor side in a mechanism transmitting the rotating force of the motor to an output shaft. <P>SOLUTION: In this actuator for the valve, the valve is opened and closed by normally and reversely rotating the output shaft for opening/closing the valve projected from the casing storing a drive part by driving a reversible rotating motor. A reverse input prevention clutch transmitting the rotating force from the motor to the output shaft side and not transmitting the rotating force from the output shaft side to the motor side is interposed in the mechanism transmitting the rotating force of the motor to the output shaft. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a valve actuator capable of preventing a valve hunting phenomenon.

  2. Description of the Related Art Conventionally, a valve actuator is known in which a valve opening / closing output shaft protruding from a casing that houses a drive unit is rotated forward and backward by driving a reversible rotary motor to open and close the valve.

  However, in the actuator as described above, when the valve is returned to the opening direction by the reaction force of the sealing sheet of the valve or the pressure of the fluid passing therethrough, the motor rotates in the direction in which the valve is closed. There is a problem that a so-called hunting phenomenon occurs in which it rotates in the opening direction even when closed.

  Therefore, in order to solve the above problem, a worm reduction mechanism has been conventionally used to prevent reverse input. However, not only the occupied space is large, but also the transmission efficiency is as poor as 30 to 50%, and the motor power There is a problem that the amount of use is large, and durability is not sufficient due to wear of the worm gear.

Object of the invention

  The present invention is a mechanism for transmitting the rotational force of the motor to the output shaft. In this mechanism, the rotational force from the motor is transmitted to the output shaft side as it is, and the rotational force from the output shaft side is not transmitted to the motor side. It is an object of the present invention to provide a valve actuator that can prevent the hunting phenomenon by interposing a clutch.

Means for solving the problem

  According to a first aspect of the present invention, there is provided a valve actuator in which a valve opening / closing output shaft projecting from a casing housing a drive unit is rotated forward and backward by driving a reversible rotary motor to open and close the valve. In the actuator, in the mechanism that transmits the rotational force of the motor to the output shaft, the rotational force from the motor is transmitted to the output shaft side as it is, and the rotational force from the output shaft side is not transmitted to the motor side. It is characterized by interposing.

  A valve actuator according to a second aspect of the present invention is the valve actuator according to the first aspect, further comprising a planetary rotation mechanism that rotates the output shaft by a handle operation.

Effect of the invention

  In the first aspect of the invention, the rotation caused by the output shaft side is completely prevented by the action of the reverse input preventing clutch, and the hunting phenomenon is completely eliminated.

  In the invention of claim 2, since the output shaft can be rotated by the handle operation even when the rotation of the motor is stopped, the valve can be manually opened and closed.

  FIG. 1 is a longitudinal side view of a valve actuator according to the present invention.

  In the figure, reference numeral 1 denotes a casing that houses a drive unit of a valve actuator, 2 denotes a reversible rotary motor, and 3 denotes an output shaft for opening and closing the valve that protrudes from the casing.

  Reference numeral 4 denotes a reverse input prevention clutch interposed between the reversible rotation motor 2 and the output shaft 3. As described in JP-A-2002-266902, an input side member to which torque is input, and torque is output. An output side member, a stationary side member whose rotation is restrained, and the stationary side member and the output side member, and the output side member and the output side member with respect to a reverse input torque from the output side member A locking means for locking the stationary side member; a lock releasing means provided on the input side member for releasing the locked state by the locking means with respect to an input torque from the input side member; the input side member; Torque transmission means provided between the output side member and transmitting the input torque from the input side member to the output side member when the locked state by the lock means is released. It is an elephant.

  5 is an internal gear having an internal tooth 5-1 and an external tooth 5-2, and is capable of free rotation with respect to the sun shaft 6 having the sun gear 6-1. A planetary rotation mechanism is constituted by a carrier gear 8 that rotatably supports planetary gears 7... 7 that mesh with the inner teeth 5-1 of the null gear 5.

  Reference numeral 9 denotes a manual handle integrated with a worm gear 9-1 that meshes with the external tooth 5-2 of the internal gear 5.

  Next, the operation of the actuator of the present invention will be described. First, when the motor 2 is energized and the rotor is rotated, the input shaft of the reverse input prevention clutch 4 is rotated through the gears a and b by the rotation of the pinion gear 2-1. The rotation of the input shaft is transmitted as it is to the output shaft, and is transmitted to the gear head output gear f through the gears c, d, and e.

  As the gear head output gear f rotates, the sun shaft 6 rotates through a gear g integrally fixed to the sun shaft 6.

  At this time, the internal gear 5 is in a fixed state because the worm gear 9-1 meshes with the external teeth 5-2, and the planetary gears 7 ... 7 meshed with the sun gear 6-1 of the sun shaft 6 rotate. The planet rotates around the sun axis 6 while meshing with the internal teeth 5-1 of the fixed internal gear 5.

  Since the carrier gear 8 that rotatably supports the planetary gears 7... 7 is rotated by the planetary rotation around the sun axis 6 of the planetary gears 7... 7, the output shaft 3 that meshes with the carrier gear 8. The integral large-diameter gear h rotates and the output shaft 3 rotates.

  A valve (not shown) connected to the stem is opened and closed by forward and reverse rotation of the output shaft 3.

  Even if the output shaft 3 is to be rotated when the motor 2 is stopped, the reverse input to the output shaft of the reverse input prevention clutch 4 is blocked and the output shaft 3 is locked.

  Next, when the handle 9 is rotated while the motor 2 is stopped, the worm gear 9-1 integrated with the handle 9 is rotated, and the internal gear 5 meshed with the external gear 5-2 is rotated. .

  At this time, the sun shaft 6 is in a fixed state by the action of the reverse input preventing clutch 5, and the planetary gears 7 ... 7 meshing with the internal teeth 5-1 are rotated by the rotation of the internal gear 5, so that the fixed sun. The planet rotates around the sun axis 6 while meshing with the sun gear 6-1 of the axis 6.

  Since the carrier gear 8 that rotatably supports the planetary gears 7... 7 is rotated by the planetary rotation around the sun axis 6 of the planetary gears 7... 7, the output shaft 3 that meshes with the carrier gear 8. The integral large-diameter gear h rotates and the output shaft 3 rotates.

The invention's effect

  As described above, according to the valve actuator of the first aspect of the present invention, the valve opening / closing output shaft protruding from the casing housing the drive unit is rotated forward and reverse by driving the reversible rotary motor. In the valve actuator that opens and closes, the rotational force from the motor is transmitted to the output shaft side as it is in the mechanism that transmits the rotational force of the motor to the output shaft, and the rotational force from the output shaft side is the motor side Since a reverse input prevention clutch that does not transmit is interposed, rotation due to the output shaft side is completely prevented by the action of the reverse input prevention clutch, and there is no hunting phenomenon. Compared with the method that uses a mechanism to prevent reverse input, the actuator can be miniaturized and the transmission efficiency is 90% or more, which is very efficient. , Power usage of the motor can also be kept low, but which can provide an actuator valve which is excellent in durability usability.

  According to the valve actuator according to claim 2 of the present invention, the valve actuator according to claim 1 is provided with the planetary rotation mechanism that rotates the output shaft by operating the handle. Since the output shaft can be rotated by operating the handle even when stopped, the valve can be manually opened and closed, and the handle does not rotate during motor rotation, which is safe.

  It is a vertical side view of the valve actuator according to the present invention.

Explanation of symbols

1 Casing 2 Motor 3 Output shaft 4 Reverse input prevention clutch 5 Internal gear

Claims (2)

  In a valve actuator that opens and closes a valve by opening and closing a valve opening / closing output shaft that protrudes from a casing that houses a drive unit by driving a reversible rotary motor, the rotational force of the motor is transmitted to the output shaft. An actuator for a valve, characterized in that a reverse input preventing clutch is interposed in the mechanism, wherein the rotational force from the motor is transmitted to the output shaft side as it is and the rotational force from the output shaft side is not transmitted to the motor side.   2. The valve actuator according to claim 1, further comprising a planetary rotation mechanism that rotates an output shaft by a handle operation.

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