JPH0416035Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an electric actuator used for positioning an object to be operated such as a valve, and particularly to one that can also be operated manually.

Conventionally, for example, when opening and closing a valve,
Self-holding electric actuators are frequently used.

FIG. 2 is a perspective view showing the outline thereof.

The self-holding electric actuator 30 is composed of an electric servo motor 31 and a speed reducer 32 connected to its output shaft. is used.

Output shaft 3 of self-holding electric actuator 30
3, that is, the output shaft of the reducer 32 has an arm 34
A spool 36 of a valve 35, which is an object to be operated, is pivotally attached to the tip of the arm 34.

When electric power is supplied to the electric servo motor 31, the electric servo motor 31 is driven to rotate, and the output shaft 33 and the arm 34 wedged thereon are rotated at a reduced speed by the reduction gear 32.

When the arm 34 rotates, the spool 36 of the valve 35 moves linearly and is switched between open and closed positions, for example.

When power supply to the electric servo motor 31 is stopped,
Rotation of the motor 31, reducer 32, and arm 34 is stopped and self-maintained at the stopped position.

This happens when a worm reducer is used because it has a self-holding function.

When the self-holding electric actuator 30 is stopped as described above, it is automatically held in the stopped position, so in such a state, the valve 35
The spool 36 cannot be operated by input.

However, there have often been cases where the valve 35 has to be operated during a power outage or the like.

In such a case, if the conventional self-holding electric actuator 30 were used as is, the valve 3
5 could not be operated at all, which was a huge problem.

The present invention was devised in order to solve the problem in view of the above-mentioned problems, and its purpose is that even if the power supply to the self-holding electric actuator is stopped and it is self-maintaining, it will still be able to be held manually by hand. An object of the present invention is to provide an electric actuator that can easily operate an object to be operated.

The electric actuator of the present invention includes an electric servo motor, a speed reducer connected to the electric servo motor and having a self-holding function, a box-shaped differential carrier, and an opposing arrangement inside the differential carrier. Two differential pinions are rotatably installed inside the differential carrier, and a differential pinion is rotatably installed inside the differential carrier and meshes with both differential pinions and is connected to the output shaft of the reducer. One side gear and
The other side gear is rotatably provided inside the differential carrier opposite to the one side gear and meshes with both differential pinions, and the operated object is linked to the other side gear. There is a lever for manual operation that is directly fixed to a part of the differential carrier, and a lever for manual operation that is installed on a part of the fixed side to connect the differential carrier and manual operation when power is supplied to the electric servo motor. It is characterized by comprising a holding solenoid that prevents rotation and allows rotation of the differential carrier and manual operation lever when power is not supplied to the electric servo motor.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a partially vertical schematic diagram showing the structure of an electric actuator according to an embodiment of the present invention.

The main parts of the electric actuator 1 include a self-holding electric actuator 2, a differential mechanism 3, a lever 4, and a holding solenoid 5.

The self-holding electric actuator 2 is composed of an electric servo motor 6 and a reducer 7, as in the past, and has a function of self-holding at a stop position by, for example, making the reducer 7 a worm reducer. ing. Of course, it is not limited to this type of structure, and other structures may also be used.

The self-holding electric actuator 2 includes an output shaft 8,
In other words, it includes the output shaft of the speed reducer 7.

The differential mechanism 3 includes a differential carrier 9 and two differential pinions 10 and 1.
1. Consists of two side gears 12 and 13.

The differential carrier 9 has a box-like shape, and a single support shaft 14 passes through the differential carrier 9 in the vertical direction and is fixed thereto. Final pinions 10 and 11 are each rotatably supported.

Two side gears 12 and 13 are rotatably provided on the left and right sides of the differential carrier 9 via bearings 15 and 16, and each side gear 12 and 13 is connected to two differential pinions 10 and 11. They mesh with each other.

The output shaft 8 of the self-holding electric actuator 2 passes through one through hole 17 of the differential carrier 9 and is wedge-attached to one (left) side gear 12, and the other (right) side gear 13 is wedged. The operated object 18 is linked.

In this embodiment, a valve (spool type valve) is illustrated as the operated object 18, and the spool 19 and the other side gear 13 are connected.

In other words, the other side gear 13 has a driven shaft 2.
0 is wedged, and this passes through the other through hole 21 bored in the differential carrier 9 and protrudes outward.The base end of the arm 22 is fixed to this, and the arm 22 is The tip and the outer end of the spool 19 are pivotally connected. That is, the rotational motion of the side gear 13 is converted into linear motion.

It goes without saying that the operated object 18 is not limited to the spool type valve as in this embodiment, but may be other types.

The lever 4 is used for manual operation, and is used for the differential carrier 9 of the differential mechanism 3.
It is fixedly installed in a part of.

The holding solenoid 5 is used to prevent or allow rotation of the differential carrier 9, and is fixed to a part of an appropriate fixed member.

In this embodiment, differential carrier 9
The spindle 23 protrudes and fits into the hook hole 24 recessed in the base of the lever 4 when the holding solenoid 5 is energized. However, the lever 4 and the differential carrier 9 are locked so that they do not rotate around the output shaft 8 and the driven shaft 20.

Conversely, when the energization is stopped, the spindle 23 of the holding solenoid 5 retracts and is no longer engaged with the hook hole 24 provided in the lever 4, preventing the rotation of the lever 4 and the differential carrier 9. is allowed.

It goes without saying that the holding solenoid 5 may not be provided opposite the lever 4, but may be provided opposite the differential carrier 9, and the hanging hole 24 may be recessed there.

The holding solenoid 5 and the electric servo motor 6 of the self-holding electric actuator 2 are connected to the power supply through a single switch, and when the switch is closed, power is supplied to both, and when the switch is opened, If this occurs, connect the wires so that power is not supplied to both.

In such a configuration, its operation will be explained next.

First, power is supplied to both the electric servo motor 6 and the holding solenoid 5 of the self-holding electric actuator 2.

When power is supplied to the holding solenoid 5, its spindle 23 protrudes and hooks into a hook hole 24 provided at the base of the lever 4. Therefore, the lever 4 and the differential carrier 9 of the differential mechanism 3 are prevented from rotating and exhibit a so-called locked state.

Under such conditions, the electric servo motor 6 is supplied with power and rotates, and the output shaft 8 is rotated at a reduced speed by the speed reducer 7.

When the output shaft 8 rotates, the left side gear 12 wedged thereon, the upper and lower differential pinions 10 and 11 meshed with it, the right side gear 13 meshed with these, and the driven shaft 20 wedged thereon are rotated. In particular, the driven shaft 20 is rotated by the output shaft 8
rotates in the opposite direction.

Therefore, the arm 22 fixed to the driven shaft 20 swings, and the spool 19 of the valve, which is the operated object 18, is rotated.
Activate.

Now, assuming that the spool 19 shown in FIG. 1 is in the valve-closed position, it is operated to bring it to the valve-open position.

If it is desired to leave the valve 18 in the open position, for example, the power supply is stopped. In this way, the rotation of the self-holding electric actuator 2 is stopped, and the valve 18 is held in the open position by its own self-holding function.

At this time, since power is not supplied to the holding solenoid 5, its spindle 23 is removed from the hook hole 24, and the differential carrier 9 is unlocked.

If the power supply to the self-holding electric actuator 2 is stopped due to a power outage or a failure in the electrical system, and if the valve 18 must be operated to close, for example, under such conditions, the lever 4 should be manually operated. Operate at.

In this way, the left side gear 12 is locked by the self-holding function of the self-holding electric actuator 2, but the differential carrier 9 can rotate around the output shaft 8 and the driven shaft 20. , this rotational force can be transmitted to the driven shaft 20.

Therefore, by manual operation of the lever 4, the valve 18
This makes it possible to operate.

As described above, according to the present invention, the following excellent effects can be achieved.

(1) Even if the power supply to a self-holding electric actuator consisting of an electric servo motor and a speed reducer is stopped and the actuator is self-holding, the operated object can be easily operated by human power.

Therefore, if it is necessary to operate the operated object even during a power outage, this can be easily done.

(2) Since the lever for manual operation is directly fixed to a part of the differential carrier, the output shaft of the reducer can be used as a rotational fulcrum for the lever, and there is no need to provide a separate rotational fulcrum for the lever. .

(3) A holding solenoid is installed on a part of the fixed side to prevent rotation of the differential carrier and manual operation lever when power is supplied to the electric servo motor, and to prevent rotation of the differential carrier and manual operation lever when power is not supplied to the electric servo motor. Since the rotation of the differential carrier and the lever for manual operation is allowed, the holding solenoid and electric servo motor can be connected to the power supply via a single switch, which improves the structure and control of the electrical system. becomes easier.

(4) A holding solenoid is installed on a part of the fixed side to prevent rotation of the differential carrier and manual operation lever when power is supplied to the electric servo motor, and to prevent rotation of the differential carrier and manual operation lever when power is not supplied to the electric servo motor. Since the rotation of the differential carrier and the lever for manual operation is allowed, the lever for manual operation cannot be operated when power is supplied to the electric servo motor. There is no risk of unexpected activation and malfunction.

[Brief explanation of the drawing]

FIG. 1 is a partially vertical schematic diagram showing an electric actuator according to an embodiment of the present invention and an object operated by the electric actuator. FIG. 2 is a schematic perspective view showing a conventional self-holding electric actuator and an operated object operated by the actuator. 1... Electric actuator, 2... Self-holding electric actuator, 3... Differential mechanism, 4... Lever, 5... Holding solenoid, 6... Electric servo motor, 7... Reduction gear, 8... Output Shaft, 9... Differential carrier, 10, 11... Differential pinion, 12, 13... Side gear, 18... Operated object.

Claims (1)

[Scope of utility model registration request] An electric servo motor 6, a speed reducer 7 connected to the electric servo motor 6 and having a self-holding function, a box-shaped differential carrier 9, and a rotating gear arranged opposite to each other inside the differential carrier 9. Two differential pinions 10 and 11 are freely rotatably installed inside the differential carrier 9 and mesh with both the differential pinions 10 and 11. One side gear 12 is connected to the output shaft 8, and both differential pinions 1 are rotatably provided inside the differential carrier 9 opposite to the one side gear 12.
the other side gear 13 meshing with 0 and 11;
Operated object 1 connected to the other side gear 13
8, a lever 4 for manual operation which is directly fixed to a part of the differential carrier 9, and a lever 4 which is provided to a part of the fixed side and which is connected to the differential carrier 9 when power is supplied to the electric servo motor 6. It is composed of a holding solenoid 5 that prevents rotation of the lever 4 for manual operation and allows rotation of the differential carrier 9 and the lever 4 for manual operation when power is not supplied to the electric servo motor 6. An electric actuator featuring: