JPH0676781U - Valve actuator - Google Patents

Abstract

(57) [Abstract] [Purpose] A resistance plate is attached to the rotary shaft of the electromagnetic brake to avoid momentary high-speed rotation, and large inertial force from the resistance plate due to sudden stop of the output shaft is released by free rotation of the resistance plate. (EN) A valve actuator which prevents a damage accident such as a reduction gear mechanism. [Structure] A resistance plate is attached to a rotary shaft of an electromagnetic brake via a one-way clutch. [Effect] There will be no damage accidents such as the speed reduction mechanism.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a valve actuator that controls the opening and closing of a valve body by driving a motor, and in particular, a valve actuator having a function of automatically opening or closing the valve when energization control becomes impossible due to a power failure or the like. It is about.

[0002]

[Prior art and its problems]

 An actuator described in Japanese Utility Model Publication No. 3-34530 is known as a conventional actuator of this type.

As shown in a perspective view showing the overall structure of FIG. 5, this actuator has a reversible rotation motor 2 in which an output shaft 1 connected to a rotation shaft of a valve body of a valve A is fixed to a rotor in a non-energized state. In the valve actuator in which the valve A is opened and closed by rotating forward and backward by 90 degrees, the output shaft 1 is rotated by the rotation of the motor 2 via the gear 21 regardless of the output shaft. 31 that pivotally supports the internal gear 3 and meshes with the inner peripheral teeth 31 ... 31 of the internal gear and the outer peripheral teeth 41 ... 41 of the gear 4 pivotally supported by the output shaft 1 so as to rotate independently of the output shaft. The gear 6 is pivotally supported by the shaft 51, the plate 6 is fixed to the output shaft 1, and the spring spring 7 is provided to be wound by the rotation of the gear 5. The spring spring 7 is prevented from being unwound when energized, and the energization is cut off. Sometimes the The structure is provided with an electromagnetic brake 8 for releasing the unwinding prevention action of the mainspring. In the figure, B is a casing that protects the entire apparatus, and 20 is a stopper that faces the inside from the lower end of the casing B. A cam 201 fixed near the lower end of the output shaft 1 abuts the output shaft. 1 can be rotated forward and backward within the range of 90 degrees. Reference numerals 30 and 40 denote microswitches that detect the rotation of the output shaft 1 and send as an electric signal whether the valve A is open or closed. The microswitches 30 are integrally fixed to the output shaft 1 by the cams 301 and 401. The contacts of 40 are turned on and off. Reference numeral 50 is a micro switch for detecting that the main spring 7 has been sufficiently wound. The contact of the micro switch 50 is turned on and off by the cam 501 rotating by the rotation of the rotary shaft 71 of the main spring 7. The electromagnet 82 of the electromagnetic brake 8 is energized, and also serves to cut off the energization of the motor 2. Reference numeral 21 denotes a gear which is integral with the rotor of the motor 2 and which meshes with the outer peripheral teeth 32 ... 32 of the internal gear 3 via a reduction gear to rotate the internal gear 3 by driving the motor 2. It constitutes a speed reducer.

The operation will be described. When the motor 2 is rotated in the direction in which the valve A is closed while the valve A is closed, the internal gear 3 has nothing to do with the output shaft 2. , Starts to rotate freely, and the gear 5 meshing with the inner peripheral teeth 31 ... 31 also rotates, but since the plate 6 on which the gear 5 is pivotally supported is integral with the output shaft 1, the gear 5 is Rotate while maintaining the position. The rotation of the gear 5 causes the gear 4 meshing therewith to rotate, the gear 72 meshing with the gear integral with the gear 4 rotates, and the rotating shaft 71 to which the gear 72 is fixed rotates. The mainspring 7 starts to be wound. When the mainspring 7 is sufficiently wound, the cam plate 501, which rotates via a gear fixed to the rotary shaft 71, kicks the contact of the micro switch 50, interrupts the electric power supply to the motor 2, and simultaneously to the electromagnet 82 of the electromagnetic brake 8. The power is supplied, and the suction plate 83 integrated with the rotating shaft 81 is attracted to prevent the rotating shaft 81, that is, the rotating shaft 71 of the mainspring 7 directly connected thereto from rotating. As a result, the mainspring 7 is fixed in the wound state, that is, in the pressure-accumulated state.

In this state, when the motor 2 is energized in the direction of opening the valve A, the internal gear 3 rotates in the opposite direction to the above, and the gear 5 meshing with the inner peripheral teeth 31 ... 31 also rotates. Since the gear 4 meshing with the gear 5 is in the fixed state as described above, the gear 5 makes a so-called planetary motion that revolves around the gear 4 while revolving around the gear 4. Since the plate 6 is pushed to rotate and the output shaft 1 integrated with the plate 6 rotates, the valve body of the valve A rotates in the opening direction.

When the valve body is opened by 90 degrees rotation of the output shaft 1, further rotation is blocked by the action of the stopper 20, and at the same time, the contact of the micro switch 30 is opened and the motor 2 is energized. It is cut off and the rotation of the motor 2 is stopped.

When it is desired to close the valve A, when the motor 2 is rotated in the direction in which the valve A is closed, the internal gear 3 and the gear 5 rotate in the reverse direction, and the gear 5 planetarily moves in the direction opposite to the above-mentioned direction. Since the plate 6 is swung in the opposite direction, the output shaft 1 rotates 90 degrees to close the valve body of the valve A. Simultaneously with the closing of the valve body, the contact point of the micro switch 40 is opened, the power supply to the motor 2 is cut off, and the rotation of the motor 2 is stopped. After that, the operation described above is repeated by driving the motor 2 to control the opening and closing of the valve A.

When an accident such as a power failure occurs in which the energization of the motor 2 cannot be controlled while the valve A is open, the energization of the electromagnet 82 of the electromagnetic brake 8 is naturally cut off. Since the adsorbing plate 83 which has been detached is released and is in a free state, the rotating shaft 71 of the main spring 7 is also free, and the restoring force of the main spring 7 wound by the above-described operation, that is, the rewinding force causes the main spring to be wound in the direction in which it is wound. Since the rotating shaft 71, that is, the gear 4, rotates in the opposite direction, the gear 5 meshing with the outer peripheral teeth 41 ... 41 also rotates, but the motor 2 is fixed when not energized, and the internal gear 3 is also fixed. In this state, the gear 5 rolls while meshing with the inner peripheral teeth 31 ... 31, and the plate 6 or the output shaft 1 is pushed by the pivot shaft 51 so that the plate 6 or the output shaft 1 is closed in the closing direction of the valve A. The valve body is automatically closed. After the power supply is resumed, the main spring 7 is wound by the above-mentioned operation to prepare for the next power failure.

In this actuator, since the rotary shaft 81 of the electromagnetic brake 8 rotates at high speed when the mainspring 7 is rewound, when the output shaft 1 is suddenly stopped by the action of the stopper 20, An extremely large load may be applied to the reduction gears in the electromagnetic brake 8, which may damage the reduction gears, or the reduction mechanism may be rotated from the rotary shaft 71 of the mainspring 7 to the rotary shaft 81 of the electromagnetic brake 8. When the transmission gears 72 and 84 are used, the gears or the key of the rotation stopper may be damaged. Therefore, a one-way clutch is interposed between the rotary shaft 81 and the gear 84 to output the output shaft 1, that is, When the rotary shaft 71 is stopped, only the rotary shaft 81 idles to release the rotational energy.

However, during normal control of opening and closing of the valve, foreign matter is caught in the valve body of the valve A, the valve body is not in the closed state, and the rotary shaft 1 does not rotate in the opening direction. When a state or a state in which a large torque is applied, the operation content becomes the winding mode of the mainspring due to the relationship of the mainspring movement due to the motor drive as described above, and even if the rotary shaft 81 of the electromagnetic brake 8 is fixed, Since 84 can rotate in the direction in which the spiral spring 7 is wound, the spring is wound too much, and the excessive winding causes the micro switch to malfunction, which may damage the entire device, or the motor may become overloaded. There was a problem such as overheating.

[0011]

[The purpose of the device]

 In order to solve the above-mentioned problems of the prior art, the present invention installs a flywheel or a resistance plate such as an air resistance fin on the rotary shaft of an electromagnetic brake that rotates integrally when the mainspring is rewound to achieve an instantaneous high speed. Avoid rotation and prevent large accidental inertia force from the resistance plate received by the rotary shaft of the electromagnetic brake due to sudden stop of the output shaft by free rotation of the resistance plate to prevent damage accidents of the reduction mechanism etc. The present invention provides a valve actuator.

[0012]

[Disclosure of device]

 The valve actuator according to the present invention is a valve actuator in which an output shaft connected to a rotary shaft of a valve body of a valve is rotated 90 degrees forward and backward by driving a reversible rotation motor to open and close the valve. The output shaft is rotatably supported by an internal gear that rotates independently of the output shaft, so that the internal gear of the internal gear and the output shaft rotate independently of the output shaft. A plate that pivotally supports a gear that meshes with the outer teeth of a gear that is pivotally supported on the output shaft is fixed to the output shaft, and a spring spring that is wound by the rotation of the gear is provided. An electromagnetic brake is provided to prevent the unwinding of the mainspring spring when the power supply is cut off, and the rotary shaft of the electromagnetic brake has a resistance plate such as a flywheel or an air resistance fin. Between the rotation shaft and the resistance plate, the resistance plate rotates integrally with the rotation shaft when the rotation shaft rotates in the direction in which the mainspring is rewound, and only the resistance plate rotates freely when the rotation shaft stops. It is characterized by interposing such a one-way clutch.

[0013]

[Function of the device]

 When the valve is opened and the power is cut off due to a power failure or the like, the electromagnetic clutch releases the constraint on its rotating shaft, so the mainspring is rewound and the rotating shaft also rotates, but at the beginning of rotation, the rotational energy is the resistance plate. Is taken as a force to rotate, the spring rotates at a low speed, the spring is rewound with the brake applied, and the valve is gently closed. When the valve closes and the output shaft stops, the rotating shaft of the electromagnetic brake also stops, but the resistance plate idles by the action of the one-way clutch regardless of the rotating shaft to release the rotational energy of the resistance plate.

[0014]

【Example】

 FIG. 1 is a side view of a valve equipped with the actuator of the present invention, FIG. 2 is a vertical side view of the actuator, FIG. 3 is a perspective view showing the overall structure of the actuator, and FIG. 4 is a mainspring and an electromagnetic clutch. FIG. 6 is a vertical sectional side view showing the relationship, the basic structure and the operation thereof are substantially the same as those of the conventional actuator, and the members performing the same operations as in FIG. The present invention is characterized in that a resistance plate 9 such as a flywheel or an air resistance fin is attached to a rotary shaft 81 of an electromagnetic brake 8 of an actuator of a conventional example via a one-way clutch 10. At the time of disconnection, when the rotating shaft 81 of the electromagnetic brake 8 is in a free state, the restoring force of the spring spring 7 that has accumulated pressure causes the gear 72 to rotate and the gear 84 meshing therewith to rotate and rotate integrally therewith. The shaft 81 rotates, but at the beginning of this rotation, energy is taken to rotate the resistance plate 9, and the mainspring spring is rewound with the brake applied, and at the same time the valve is gently closed, Even if the rotation shaft 81 of the electromagnetic clutch 8 stops due to the stop of the output shaft 1, the resistance plate 9 idles due to the action of the one-way clutch 10 and the resistance plate 9 has it. Rolling energy is released without the any of the action, not to disrupt the electromagnetic vibration over reduction mechanism or external reduction mechanism key in 8, and the like.

[0015]

[Effect of device]

 According to the actuator of the present invention, a resistance plate such as a flywheel or an air resistance fin is attached to the rotary shaft of the electromagnetic brake via a one-way latch, so that an appropriate brake is applied when the mainspring is rewound. The valve slowly closes, and even if the output shaft suddenly stops due to the closing, only the resistance plate spins, releasing extra rotational energy and not burdening the reduction mechanism. Therefore, there is no accident such as the winding of the mainspring excessively as in the conventional example, the malfunction of the microswitch caused by this excessive winding, which destroys the entire device, and the motor overheats in the overload locked state. It was

In this type of actuator, if the rotor of the driving motor is not fixed when the motor is not energized, the internal gear rotates when the valve is closed by the action of the spring, and the output shaft is Since the valve body opens in the half-open state by rotating in the valve opening direction, it is necessary to use a non-excitation actuated motor with an electromagnetic brake or an induction motor with a built-in friction brake. There is a risk that slip will occur due to the influence of the atmosphere such as humidity and humidity, and if a slip occurs, there is a danger that the valve will be in the half-opened state as described above. An inductor that semi-permanently has a holding force, which is the holding torque at rest with no current applied to the stator or rotor. Coutance type synchronous motor was used.

[Brief description of drawings]

FIG. 1 is a side view of a valve including an actuator of the present invention.

FIG. 2 is a vertical sectional side view of the actuator. .

FIG. 3 is a perspective view showing the overall structure of the actuator.

FIG. 4 is a vertical sectional side view showing a relationship between a mainspring and an electromagnetic clutch.

FIG. 5 is a perspective view showing the overall structure of a conventional actuator.

[Explanation of symbols]

 A valve B casing 1 output shaft 2 motor 3 internal gear 4 gear 5 gear 6 plate 7 spiral spring 8 electromagnetic brake 9 resistance plate 10 one-way clutch

Claims (2)

[Scope of utility model registration request] 1. A valve actuator in which an output shaft 1 connected to a rotary shaft of a valve body of a valve A is rotated 90 degrees forward and backward by driving a reversible rotation motor 2 to open and close the valve A. Therefore, the output shaft 1 pivotally supports an internal gear 3 that rotates independently of the output shaft via a gear 21 by the rotation of a motor 2, and the inner peripheral teeth 31 ... 31 of the internal gear and the output shaft 41 is fixed to the output shaft 1 while a plate 6 pivotally supporting a gear 5 meshing with outer peripheral teeth 41 ... 41 of a gear 4 pivotally supported on the output shaft 1 independently of the output shaft 1 is attached to the output shaft 1. A spiral spring 7 wound by the rotation of the gear 5 is provided, and an electromagnetic brake 8 is provided to prevent the spiral spring from unwinding when energized, and to release the unwinding prevention action of the spring when energized, and a rotary shaft 81 of the electromagnetic brake. F A resistance plate 9 such as a flywheel or an air resistance fin is attached, and when the rotation shaft 81 rotates in the direction in which the mainspring 7 is rewound, the resistance plate 9 rotates between the rotation shaft 81 and the resistance plate 9. A valve actuator characterized by interposing a one-way clutch 10 which rotates integrally with a shaft 81 and in which only the resistance plate 9 freely rotates when the rotating shaft stops. 2. The valve actuator according to claim 1, wherein the motor 2 of claim 1 is an inductance type synchronous motor.