JP2919763B2 - Motor actuator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor actuator, and more particularly, to a motor actuator capable of preventing abnormal noise by eliminating unevenness of a rotating shaft.

[0002]

2. Description of the Related Art Conventionally, there has been known a motor actuator which forms a worm on a rotating shaft of a motor and transmits rotation to a wheel gear (gear).

[0003] In this motor actuator, a bearing is provided at the tip of the rotating shaft because the rotating shaft is formed long, but a clearance is formed between the rotating shaft and the bearing.

[0004] However, due to the formation of the clearance, the rotation shaft may be separated from the bearing under a predetermined rotation condition, thereby generating abnormal noise.

Therefore, in order to prevent this abnormal noise, a technique of bringing a bearing into contact with the tip of the rotating shaft has been considered. Regarding this, for example, Japanese Utility Model Laid-Open No. 52-21648,
JP-A-56-85747 or JP-A-1-141.
No. 946.

Here, the technology disclosed in Japanese Utility Model Laid-Open Publication No. 52-21648 or Japanese Utility Model Laid-Open Publication No. 56-85747 is disclosed.
The adjustment screw allows the bearing to be adjusted in the axial direction of the rotating shaft. Therefore, there is a problem that the adjustment with the adjusting screw must be performed.

In the technique disclosed in Japanese Utility Model Laid-Open No. 1-141946, the dimensions cannot be adjusted because the bearing is separate from the motor case. Then, the dimensional accuracy must be increased, and the production becomes difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a motor actuator which can prevent the rotation shaft from being roughened without performing any adjustment work. is there.

[0009]

According to a first aspect of the present invention, a motor is housed in a motor case, and a worm and a wheel gear (gear) formed on a rotating shaft of the motor are provided. in the reduction gear is configured motor actuator, the rotary shaft is applied the pressing force to a portion of the pressing force at an assimilable adjusting pressing means, and in sliding contact with the sliding contact portion, the sliding contact portion The end of the rotating shaft
Direct contact diagonally in the opposite direction to the gear
It is characterized by doing .

According to a second aspect of the present invention, there is provided the motor actuator according to the first aspect, wherein a stopping means for stopping the stored outer frame of the motor from moving in the axial direction or the direction perpendicular to the axis of the rotating shaft; Elastic means interposed between the restraining means and the outer frame, for absorbing a part of the pressing force of the restraining means against the outer frame in the direction of the restraining means. Applying a pressing force to the outer frame via a rotating shaft ,
The elastic means absorbs a part of the pressing force.

According to a third aspect of the present invention, in the motor actuator according to the second aspect, the stopping means holds an outer side of a bearing provided on an outer frame of the motor, and the elastic means comprises an outer side of the bearing. Characterized in that it is an elastic member to be attached to the device.

According to a fourth aspect of the present invention, in the motor actuator according to the second or third aspect, the sliding portion is in sliding contact with a front end or a rear end of the rotating shaft, and the elastic means is provided. Is characterized in that a part of the pressing force pressed from the sliding contact portion is absorbed.

According to a fifth aspect of the present invention, in the motor actuator of the first aspect, the stationary portion and the rotating portion inside the motor are so formed as to generate a magnetic force for pressing the rotor in the axial direction of the rotating shaft. The rotating shaft is slidably contacted with the slidable portion by applying the pressing force by the magnetic force.

[0014]

[0015]

According to the first aspect of the invention, the pressing of the pressing shaft causes the rotating shaft to directly slide on the sliding contact portion, thereby preventing the rotating shaft from being flattened. In addition, since the pressing force on the rotating shaft is partially absorbed by the adjusting pressing means, no excessive pressing force is naturally applied. Then, even if components are not manufactured with a high degree of accuracy, it is possible to prevent the rotation shaft from being roughened without performing an adjustment operation. In other words, the error can be naturally absorbed by the adjustment pressing means. In the sliding contact area, the worm is a wheel
Slide away from the gear. in this way
The worm and the wheel gear (gear) are too close together
And does not occur due to contact between the bottom of the tooth and the tip of the tooth.
Also prevents the meshing noise.

According to a second aspect of the present invention, the first aspect of the present invention is embodied. The sliding portion is pressed against the rotating shaft of the motor stopped by the stopping means. In addition, the rotation shaft is prevented from being unsteady. Since the elastic means is interposed between the stopping means and the outer frame of the motor, a part of the pressing force is absorbed by the elastic means.

This is further embodied in the third aspect of the present invention. That is, according to the third aspect of the present invention, an elastic member such as rubber is mounted on the motor, and the excessive pressing force is absorbed by the elastic member.

According to the fourth aspect of the present invention, the rotating shaft has the leading end sliding on the sliding contact portion or the rear end sliding on the sliding contact portion.

Here, in order to bring the tip end side of the rotating shaft into sliding contact with the sliding contact portion, an elastic means is provided on the rear side of the motor. Also, to make the rear end side of the rotating shaft slide in contact with the sliding part,
The elastic means will be provided on the front side of the motor.

Next, in the invention according to claim 5, the pressing force is applied by a magnetic force. That is, by adjusting the relative position between the stationary part and the rotating part inside the motor, a magnetic force for moving the rotor in the direction of the rotation axis is generated. In addition, the force by such a magnetic force is called preload.

By doing so, the rotating shaft can be pressed against the sliding contact portion by the magnetic force to make sliding contact. In addition, since the pressing force at this time is due to the magnetic force, the excess pressing force is absorbed.

[0022]

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing a motor actuator according to an embodiment.
This is for operating the vehicle air conditioner.

As shown in FIG. 1, the motor actuator 10 has a worm 14 formed on a rotating shaft 12a of the motor 12 meshed with a wheel gear (gear) 16, and the rotation of the wheel gear (gear) 16 is reduced by a reduction gear. The speed is reduced at 18 and transmitted to an output shaft (not shown). The motor 12 has an O-ring 20,
22 are mounted.

FIG. 2 is an exploded perspective view in which the wheel gear (gear) 16 and the reduction gear 18 are omitted from the motor actuator 10 shown in FIG. As shown in FIG. 2, the motor actuator 10 includes an outer case 24 and an inner case 2.
And the inner case 26 includes the motor 12, the wheel gear (gear) 16, the reduction gear 18, and the O-ring 2.
The inner case 26 is housed in the outer case 24. Although not shown, the outer case 24 is covered with a case cover so as to cover components housed inside.

The most significant feature of this embodiment is that the rotating shaft 12a of the motor 12 slides on a sliding portion 28 formed on the outer case 24 and a pressing force is applied by the O-ring 22, Matters related to this will be described in detail.

As described above, the O-rings 20 and 22 are mounted on the motor 12 (see FIG. 1). Each of the O-rings 20 and 22 has an anti-vibration property, and blocks vibration between the motor 12 and the inner case 26. Further, the O-ring 20 has only this vibration-proof property, whereas the O-ring 22 has elasticity in addition thereto.

Next, the sliding contact portion 2 formed on the outer case 24
Numeral 8 is such that the tip of the rotating shaft 12a of the motor 12 comes into contact with the motor.

More specifically, when the motor 12 is housed in the inner case 26, the rotating shaft 12a on which the worm 14 is formed projects, and the tip of the projecting rotating shaft 12a comes into contact with the sliding contact portion 28. It has become.

Further, the motor 12 is held inside the inner case 26 so as to move in the axial direction of the rotating shaft 12a by the elastic deformation of the O-ring 22, but not to move in the direction perpendicular to the rotating shaft 12a. ing. Specifically, the restraining portions 26a and 26b formed on the inner case 26 restrain and hold the outside of the bearing (not shown) of the motor 12 via the O-rings 20 and 22, and the elastic deformation of the O-ring 22 Except for some movement, it is prevented from moving in the axial direction of the rotating shaft 12a and in the direction perpendicular to the axis.

The sliding portion 28 is formed in a groove shape along the mounting direction so as not to hinder the mounting of the motor 12, and the groove has such a size as to slightly press the tip of the rotating shaft 12 a of the motor 12. It has become something. Further, the groove forming the sliding contact portion 28 has an oblique shape whose bottom faces the rotating shaft 12a.

In other words, as shown in FIG. 1, the sliding portion 28 is configured to press the rotating shaft 12a away from the wheel gear 16 to make contact therewith.

When the sliding portion 28 presses the rotary shaft 12a, the O-ring 22 is elastically deformed, so that the motor 12 moves slightly in the direction in which the motor 12 itself is pressed (that is, in the retreating direction). A force that pushes the tip of the rotating shaft 12a back to the sliding portion 28 is applied by the elastic force.

FIG. 3 shows the operation at this time. FIG. 4 is an enlarged view of the vicinity of the contact between the sliding contact portion 28 and the rotating shaft 12a in FIG.

In FIG. 3, the force f is O as described above.
This is a force due to the elastic force of the ring 22. When a material having a small elastic force is used as the O-ring 22, f becomes small, and when a material having a large elastic force is used, f becomes large.

Here, the rotating shaft 12a and the sliding portion 2
8, the pressing force in the axial direction is taken as the force applied from the rotating shaft 12a to the sliding contact portion 28, but may be taken as the force applied from the sliding contact portion 28 to the rotating shaft 12a. it can.

That is, in the former case, the O-ring 22
The pressing force in the axial direction was captured as the force f for pressing the rotating shaft 12a against the sliding portion 28 by the elastic force of.

On the other hand, in the latter case, the sliding contact portion 2
8 is a force f1 'pressing the rotating shaft 12a (not shown)
And the force f2 'absorbed by the deformation of the O-ring 22
The above pressing force can also be captured as a combined force f ′ (not shown) with the pressing force (not shown). In this latter case, f '
= F1'-f2 ', and the directions of f and f' are reversed. In any case, a force (f or f ') acts in the axial direction between the rotating shaft 12a and the sliding portion 28.

Next, in FIG. 3, the force f is
Are oblique (in a tapered shape), they are dispersed in a direction perpendicular to the axis, and this force is indicated by F.

The relationship between the force F and the force f is expressed by F = f (sinθ · cosθ- μcos 2 θ). Here, μ is the rotation shaft 12a and the sliding contact portion 2
And θ is preferably about 8 °.

Thus, the force F is applied in the direction orthogonal to the rotating shaft 12a.
Is added, the rotation of the rotating shaft 12a is suppressed. Then, it is possible to prevent the abnormal noise due to the unevenness of the rotating shaft 12a.

The force f, which is a prerequisite for generating the force F,
Is caused by the elasticity of the O-ring 22, so that it is not necessary to perform a troublesome adjustment for obtaining an appropriate pressing force. Alternatively, in other words, as described above, a part of the pressing force is absorbed by the elasticity of the O-ring 22, so that the pressing force f ′ can be set to an appropriate pressing force without any troublesome adjustment. .

In this embodiment, the sliding portion 28 and O
The ring 22 constitutes the adjusting and pressing means in the first aspect.

FIG. 4 is a diagram showing a modification of the above embodiment. In FIG.
A worm 34 is fixed to a rotating shaft 32a of a motor 32. The worm 34 has a steel ball 36 at a tip thereof in a state where a part thereof is exposed, and the steel ball 36 slides on a sliding contact portion 38. It has become.

The difference from the above-described embodiment is that a steel ball 36 is used in a portion that is in sliding contact with the sliding portion 38. Then, the rotating shaft 32a only needs to be inserted into the hole 34a formed in the worm 34 as far as it will go.
4 (see FIG. 2) to adjust the length of the worm 1
It is not necessary to adjust the meshing between the gear 4 and the wheel gear (gear) 16. Moreover, the steel ball 36 can be made of a material suitable for friction.

Next, FIG. 5 is a diagram showing another modification of the above embodiment. The feature in the figure is that the sliding portion 40 comes into sliding contact with the outer peripheral surface of the worm 42. Even with such a configuration, the same effects as described above can be achieved.

Next, the state of the sliding contact between the sliding contact portion and the rotary shaft, which can achieve the effect of the present invention, including the above-mentioned ones is shown in FIG.
Shown in In the figure, (A) is a state in which it is slid in contact with the shaft at a right angle, (B) is a state in which it is pressed away from the wheel gear (gear) 16 (see FIG. 1), and (C) is a wheel gear (gear) in reverse. 16 (see FIG. 1), a state where it is pressed in a direction to approach it, (D) a state where a U-shaped groove (or V-shaped groove may be formed) in the sliding contact portion, and (E) a state where a depression is formed in the sliding contact portion ,
(F) shows a state in which a projection is provided on the sliding contact portion as shown in FIG. 5 described above. In any of these states, it is possible to prevent the rotating shaft from being rough as described above.

Further, the present invention can be implemented as shown in FIG. That is, in FIG.
A part of the outer frame (yoke) of No. 4 is cut and bent to form a support piece 44a obliquely outward.
Presses the stopper 46a of the inner case 46. Since the support piece 44a is inclined, the support piece 44a has elasticity and presses the stopping portion 46a. Then, the motor 44 is pressed backward.

FIG. 8 is a schematic enlarged view showing the rear end of the motor 44 shown in FIG. As shown in FIG. 8, the rotating shaft 48 of the motor 44 has an end protruding. Then, as described above, since the motor 44 is pressed backward, the end of the rotating shaft 48 comes into contact with the inner case 46. Then, in this case as well, it is possible to prevent the rotation shaft from being roughened.

Alternatively, as a modified example of the embodiment, it is possible to prevent the rotation shaft from rotating by utilizing the preload of the motor.

That is, in a DC motor, a magnetic flux is generated by a stationary portion having a permanent magnet or an electromagnet, and when a current flows through the armature winding of the rotating portion, the rotating portion receives a force from the magnetic field and rotates by an electromagnetic force. I do.

Here, the relative position between the stationary part and the rotating part,
Specifically, depending on the relative position between the permanent magnet or electromagnet and the armature winding, the electromagnetic force acts not only in the direction of rotating the rotating part but also in the direction of pressing the rotating part in the direction of the rotating axis. Can be (preloaded).

Therefore, by positioning the stationary part and the rotating part relatively so that the electromagnetic force acts in the direction of the rotating axis, the rotating shaft can be pressed against the sliding contact part, and the sway can be prevented.

Further, since this pressing force is due to the electromagnetic force, a part of the pressing force is absorbed.

In this case, the sliding portion can be provided inside the motor. That is, as shown in FIG. 9, a sliding contact plate 54 that obliquely contacts the rear end of the rotating shaft 52 is provided inside the motor 50, and the rotating shaft 52 can slide on the sliding contact plate 54. .

In this way, since the motor 50 itself has the means for preventing spilling, it is not necessary to provide means for preventing squirting in a case or the like.

[0058]

According to the present invention, since the pressing force is naturally adjusted by the adjusting pressing means, not only is unnecessary precision required for the manufacture of the parts, but also the rotation shaft is unwound without performing the adjusting operation. Can be prevented.

[0059] In addition, it is possible that the engagement of the worm and wheel gear does not become excessive, also reduce sound meshing generated from the excessive of.

[0060]

[Brief description of the drawings]

FIG. 1 is a plan view showing a motor actuator according to an embodiment.

FIG. 2 is an exploded perspective view of the motor actuator of FIG. 1 with some parts omitted;

FIG. 3 is a partially enlarged view of FIG.

FIG. 4 is a plan view showing the deformability of the embodiment corresponding to FIG.

FIG. 5 is a plan view showing another modification of the embodiment corresponding to FIG. 3;

FIG. 6 is a diagram illustrating a list of sliding contact states between a rotating shaft and a sliding contact portion;

FIG. 7 is a plan view showing another modification of the embodiment.

8 is a schematic enlarged view of FIG. 7 with a part cut away.

FIG. 9 is a plan view showing still another modification of the embodiment.

[Explanation of symbols]

 10, 30 Motor actuator 12, 32, 44, 50 Motor 12a, 32a, 48, 52 Rotating shaft 14, 34, 42 Worm 16 Wheel gear (gear) 18 Reduction gear 22 O-ring (elastic means) 44a Support piece (elastic means) 24) Outer case (motor case) 26, 46 Inner case (motor case) 26a, 26b, 46a Suppression part (suppression means) 28, 38, 40 Sliding part 54 Sliding plate (Sliding part)

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tokuhisa Takeuchi 1-1-1 Showa-cho, Kariya-shi, Aichi Japan Inside Denso Co., Ltd. (56) References JP-A-5-252692 (JP, A) 78173 (JP, U) Shokai 57-18865 (JP, U) Shohei 1-1141946 (JP, U) Shokai 56-85747 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) H02K 7/116 F16H 1/16 F16H 57/02 531

Claims (5)

(57) [Claims] 1. A motor actuator in which a motor is housed in a motor case and a reduction gear is formed by a worm and a wheel gear (gear) formed on a rotation shaft of the motor, wherein the rotation shaft has a pressing force of parts is added the pressing force at an assimilable adjusting pressing means, and in sliding contact with the sliding contact portion, the sliding contact portion, the end portion of the rotary shaft, the wheel gear
(Gear) to make direct contact obliquely in the opposite direction
Characterized motor actuator. 2. The motor actuator according to claim 1, wherein the stopping means stops the outer frame of the stored motor from moving in the axial direction of the rotating shaft or in a direction perpendicular to the rotating shaft. is interposed between the outer frame has a resilient means for absorbing a part of the pressing force in the direction of the stop means for the outer frame, the sliding contact portion through the rotary shaft the A motor actuator, wherein a pressing force is applied to an outer frame, and the elastic means absorbs a part of the pressing force. 3. The motor actuator according to claim 2, wherein the stopping means holds an outside of a bearing provided on an outer frame of the motor, and the elastic means is an elastic member mounted outside the bearing. A motor actuator, characterized in that: 4. The motor actuator according to claim 2, wherein the sliding portion is in sliding contact with a front end or a rear end of the rotating shaft, and the elastic means is in the sliding portion. A motor actuator characterized by absorbing a part of a pressing force pressed from a motor. 5. The motor actuator according to claim 1, wherein a stationary portion and a rotating portion inside the motor are arranged so as to generate a magnetic force for pressing a rotor in an axial direction of the rotating shaft. A motor actuator characterized in that a pressing force is applied so that the rotating shaft slides on the sliding contact portion.