JPH0811036Y2 - Electric actuator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to improvement of an electric actuator used as a drive source for operating a door or the like of an air conditioner for a vehicle.

(Prior Art) Recent automobiles have been electrified, and electric motors have been used to control the opening and closing of the window glass of the passenger lift doors and the operation of wind direction switching dampers (commonly known as doors) in automobile air conditioners. Actuator is used.

This electric actuator includes, for example, as shown in FIG. 4, a bottomed case 1a and a lid 1b for closing the case 1a.
A motor M and a motor M in a casing 1 made of
A reduction mechanism 5 including a worm 2, a worm wheel 3 and the like, an output gear 6 rotated by the reduction mechanism 5, an output shaft 7 rotated by the output gear 6,
It has a potentiometer 9 that rotates in synchronization with the rotation of the output shaft 7 and detects the rotational position of the output gear.

Then, a coupler k having a connector pin 12 provided on a side portion of the casing 1 is connected to a coupler for power supply (not shown).
When the motor M is operated and the power is connected, the output shaft 7 protruding from the lid 1b is rotated, and a rotation link (not shown) attached to the end of the output shaft 7 is rotated. By this rotation, various doors connected via a control cable or the like are operated, and the opening degree of the door is controlled.

In such a conventional electric actuator, the worm 2 and the worm wheel 3 mesh with each other to cause the worm 2 to move.
There is a possibility that a thrust force is generated on the motor M, which is applied to the motor M to cause vibration, or the worm 2 moves axially with respect to the rotation shaft 8 of the motor M.

As a means for eliminating such inconvenience, the spring member 13 is brought into contact with the tip of the worm 2, the spring member 14 is brought into contact with the rear end of the motor M, or the rear end of the worm is hit. Attempts have been made to provide a worm drop prevention wall 15 in contact therewith.

(Problems to be solved by the invention) However, in such a conventional electric actuator, even if the movement of the worm 2 or the motor in the thrust direction can be prevented to some extent, the rotating shaft 8 of the motor
There is a fear that it is impossible to prevent noise (so-called gogging sound) due to the eccentric blurring or the like.

Incidentally, as disclosed in Japanese Utility Model Laid-Open No. 61-114,960, a technique for preventing eccentric blurring of a rotating shaft of a motor is known. However, the technique disclosed in this publication has a disadvantage that axial rattling due to the thrust force acting on the worm cannot be prevented, and a means for preventing it must be provided separately. are doing.

The present invention has been made in order to solve the drawbacks and problems associated with the above-described conventional technology. It is possible to prevent rattling in the thrust direction and slipping out of the worm due to the thrust force acting on the worm. It is an object of the present invention to provide an electric actuator that is capable of preventing vibration due to eccentric blurring, has less noise, and has a small number of parts and is easy to be assembled.

[Means for Solving the Problem] (Means for Solving the Problem) The present invention for achieving the above object is directed to a motor, a worm connected to a rotating shaft of the motor, and a reduction mechanism including the worm in a casing. In an electric actuator having an output gear rotated by, a leaf spring having a radial repulsion portion and an axial repulsion portion is mounted in the casing, and the radial repulsion portion is fixed. Has a shape that is bent in a U-shaped cross section continuously to the substrate portion that is a portion to be formed, and is in contact with the outer periphery of the rotation shaft of the motor in a radial direction to repel the rotation shaft, The resilient part is formed continuously with the radial resilient part, and is in contact with the end of the worm so as to repel the worm in the axial direction.

The leaf spring may be fastened to a bracket to which the motor is attached together with a set screw for attaching the motor, or may be integrally formed with the bracket to which the motor is attached.

(Operation) With this configuration, since the radial resilient portion having the U-shaped cross section of the leaf spring is in contact with the rotation shaft of the motor, noise due to eccentric movement of the rotation shaft is reduced. .

Even if the worm and the worm wheel mesh with each other and thrust force is generated and the worm is pushed toward the motor side, the axial repulsion part formed continuously with the radial repulsion part of the leaf spring will generate this force. Therefore, the worm does not come off, and the thrust force does not cause vibration in the motor or the worm, which causes noise.

Further, since one leaf spring has the above-described action, the number of parts does not increase and the assembling thereof is easy.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view of an electric actuator according to an embodiment of the present invention, FIG. 2 is a schematic view showing a main part of the actuator, and FIG. 3 is a schematic view showing another embodiment of the present invention. It is a schematic diagram of a part, and the members common to those shown in FIG. 4 are denoted by the same reference numerals, and the description thereof will be partially omitted.

The electric actuator 20 has a bottomed case 1a, and on the case 1a, a motor M, a speed reduction mechanism 5 connected to the motor M, an output gear 26 rotated by the speed reduction mechanism 5, An output shaft 7 rotated by the output gear 26 and a potentiometer 9 having a potentiometer gear 58 that rotates in synchronization with the rotation of the output shaft 7 are provided. The case 1a is closed by a lid 1b, and the tip of the output shaft 7 is exposed to the casing 1 including the case 1a and the lid 1b.

In the present embodiment, the motor M has a set screw 22 on a bracket 21 arranged so as to partition the inside of the casing 1.
It is fixed at. A leaf spring 23 is fixed to the bracket 21 by a set screw 22 on the side opposite to the side where the motor M is attached. Therefore, the leaf spring 23 and the motor M are fastened together by the set screw 22.

As shown in FIG. 2, the leaf spring 23 has a radial repulsion portion 24 that is in contact with the outer periphery of the rotation shaft 8 of the motor M so as to repel the rotation shaft 8 in the radial direction. In this embodiment, the radial direction repellent portion 24 is attached to the bracket by the set screw 22 in the leaf spring 23.
It is formed by continuously bending a substrate portion 26, which is a portion fixed to 21, to have a U-shaped cross section.

An axial resilient portion 25 is formed on the tip end side of the leaf spring 23 continuously with the radial resilient portion 24. This axial repulsion part
The worm 25 is configured to contact the rear end surface of the worm 2 so as to repel the worm 2 toward the tip end side in the axial direction.

According to such an electric actuator 20, the leaf spring 23
Radial resilient portion 24 having a U-shaped cross section
Is in contact with the rotating shaft 8 of the motor M, the rotating shaft 8
The noise due to the eccentric shake is reduced.

Further, even if the worm 2 and the worm wheel 3 mesh with each other to generate a thrust force and the worm 2 is pushed toward the motor M side, the axial direction formed continuously with the radial resilient portion 24 of the leaf spring 23. Since the repellant portion 25 receives this force, the worm 2 does not come off with respect to the rotary shaft 8 and the thrust force does not cause vibrations in the motor M or the worm 2 to cause noise.

Further, since the leaf spring 23 alone has the above-described action, the number of parts does not increase and the assembly of the electric actuator does not become complicated.

It should be noted that the present invention is not limited to the above-described embodiments, but can be variously modified within the scope of the present invention.

For example, as shown in FIG. 3, the leaf spring 23a may be formed integrally with the bracket 21a. In this case, the number of parts can be further reduced.

[Advantages of the Invention] As described above, according to the present invention, the leaf spring having the radial resilient portion and the axial resilient portion is mounted in the casing, and the radial resilient portion is It has a shape that continuously bends in a U-shape in cross section to the base plate portion that is a fixed portion, and is in contact with the outer circumference of the rotation shaft of the motor so as to repel the rotation shaft in the radial direction. The direction repulsion portion is formed continuously with the radial repulsion portion and is in contact with the end of the worm so as to repel the worm in the axial direction. It is possible to prevent the rattling in the thrust direction due to the force and the vibration due to the eccentric blurring of the rotating shaft of the motor, preventing the worm from coming off and reducing the noise, and yet the number of parts is small. , Assembly of electric actuator becomes complicated It has the excellent effect of never happening.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an electric actuator according to an embodiment of the present invention, FIG. 2 is a schematic view showing a main part of the actuator, and FIG. 3 is a schematic view showing another embodiment of the present invention. FIG. 4 is a schematic sectional view of an electric actuator according to a conventional example. 1 ... casing, 2 ... worm, 3 ... worm wheel,
5 ... Reduction mechanism, 8 ... Rotating shaft, 20 ... Electric actuator,
21, 21a ... Bracket, 22 ... Set screw, 23,23a ... Plate spring,
24 ... radial repulsion part, 25 ... axial repulsion part, M ... motor.

Claims (3)

[Scope of utility model registration request] 1. A motor (M) in a casing (1),
Worm (2) connected to the rotating shaft of this motor (M)
In the electric actuator (20) having the output gear (7) rotated by the speed reduction mechanism (5) including the worm (2), the radial repulsion part (24) and the axial repulsion part (25). ) Is mounted in the casing (1), and the radial direction repellent portion (24) has a cross section continuous to the base portion (26) which is a fixed portion. It has a U-shaped bent shape and is in contact with the outer circumference of the rotary shaft (8) of the motor (M) so as to repel the rotary shaft (8) in the radial direction. The part (25) is formed continuously with the radial repulsion part (24) and is in contact with the end of the worm (2) so as to repel the worm (2) in the axial direction. An electric actuator characterized in that 2. The leaf spring (23) is mounted on a bracket (21) to which the motor (M) is attached.
The electric actuator according to claim 1, wherein the electric actuator is fastened together with a set screw (22) for mounting the. 3. The leaf spring (23a) is the motor (M).
The electric actuator according to claim 1, wherein the electric actuator is integrally formed with a bracket (21a) to which is attached.