JP3875466B2 - Actuator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an actuator provided with a gear reduction mechanism.
[0002]
[Prior art]
Conventionally, as shown in FIG. 4, the motor 43 is held by the case body 42 with a gap between the motor 43 and the case body 42, and the tip of the motor shaft 44 houses the first gear 45. The bottom surface of the recess 46 is rotatably supported. When the motor 43 is driven, power is transmitted to the output shaft 47 via the first gear 45 attached to the motor shaft 44.
[0003]
[Problems to be solved by the invention]
However, in the actuator 41, since there is a gap between the motor 43 and the case body 42, when the motor 43 is assembled to the case body 42, at least the gap is the motor 43, that is, the motor shaft 44 and the first gear. When 45 is tilted with respect to the axial direction, the end of the first gear 45 may abut against the opening of the recess 46 in which the first gear 45 is accommodated, and the first gear 45 is deformed. There was a possibility.
[0004]
The present invention has been made to solve the above-described problems, and an object of the present invention is to improve the assembling property and the quality of parts after assembling without increasing the number of parts.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, the invention according to claim 1 includes a motor having a motor shaft to which a gear is attached, a motor housing portion and a recess that is continuous with the housing portion and houses the gear. An actuator including a case body to which the motor is assembled from one end in the axial direction, wherein a gap is formed between the motor and the inner wall of the housing, and the motor shaft is opposite to the motor from the axial end surface of the gear. The extension portion was formed to be longer than the axial height of the recess.
[0006]
According to a second aspect of the present invention, in the actuator according to the first aspect, a guide portion of the extension portion is formed on the bottom surface of the concave portion.
[0007]
According to a third aspect of the present invention, in the actuator according to the first or second aspect, the case body is provided with a support portion that supports the tip portion of the extension portion.
[0008]
Therefore, according to the first aspect of the present invention, there is provided a motor having a motor shaft to which a gear is attached, a housing portion of the motor and a recess that is continuous with the housing portion and houses the gear, and is one end side in the axial direction of the motor. An actuator including a case body to which the motor is assembled, wherein a gap is formed between the motor and the inner wall of the housing portion, and the motor shaft extends from the axial end surface of the gear to the opposite side of the motor. The extended part was formed, and the extended part was formed longer than the axial height of the concave part. In this case, since the extension is initially formed longer than the height of the recess, the tip of the extension reaches the bottom of the recess when the motor is assembled to the case body. The extension side does not come into contact with the vicinity of the opening of the recess, and the gear is not damaged during assembly. Therefore, abnormal noise and malfunction due to gear deformation are eliminated.
[0009]
According to the second aspect of the present invention, the extension guide portion is formed in the recess. Therefore, since the motor is assembled to the case body with the tip of the extension portion guided by the guide portion of the recess during assembly, the gear is also guided together with the extension portion, so that the gear contacts the inner peripheral wall of the recess during assembly. Therefore, there is no deformation of the gear due to contact.
[0010]
According to the third aspect of the present invention, the case body is provided with the support portion that supports the tip portion of the extension portion. Therefore, since the tip of the extension portion is supported by the support portion of the case body when assembled, even when the motor is driven and force is applied to the motor shaft, the motor shaft is prevented from being bent. Vibration and noise due to shaft runout can be prevented.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1 is a front view of an actuator 1 according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line AA of FIG. FIG. 3 is a cross-sectional view showing a state in which the motor 5 is assembled to the motor housing portion 9 of the case body 2 in the direction of arrow B.
[0012]
As shown in these drawings, the actuator 1 includes a case body 2. The case body 2 includes a motor housing portion 9 that houses the motor 5, a recess portion 26 that houses the first gear 11, and a gear housing portion 30 that houses a reduction gear, which will be described later. The motor 5 is housed in the motor housing portion 9 via the O-ring 8 with at least a part of the outer periphery of the motor 5 having a gap from the inner wall of the motor housing portion 9. The opening 19 of the motor housing 9 is covered with the cover 4, and the opening 19 side of the motor 5 is supported by the cover 4 via an O-ring and support legs 31. The cover 4 is formed with a connector 6 for supplying power to the motor 5. The opening of the gear housing 30 is covered with the lid 3.
[0013]
The motor 5 has a motor shaft 10 extended toward the gear housing portion 30, and a first gear 11 is attached to the motor shaft 10 so as to rotate integrally. The motor shaft 10 has an extension 15 that extends from the first gear 11 to the gear housing 30. A recess 26 for housing the first gear 11 is formed on the rear side in the axial direction of the gear housing portion 30, and a shaft hole 21 as a guide portion for guiding the extension portion 15 is formed on the bottom surface thereof. Has been. Therefore, in a state where the extension portion 15 is assembled, the motor 5 side of the extension portion 15 is inserted into the shaft hole 21 formed in the case body 2, and the tip end portion 13 is pivoted to the support portion 32 formed in the lid body 3. Be supported.
[0014]
The second gear 12 is rotatably supported by the case body 2 and the lid body 3, and the second gear 12 meshes with the first gear 11 and is rotatable according to the rotation of the motor shaft 10. A third gear 14 is disposed on the side of the second gear 12 in a state of being rotatably supported by the case 2 and the lid 3. The fourth gear meshes with the second gear 12, and rotation is transmitted. The output shaft 16 includes a bearing 18 whose intermediate portion is fixed to the lid 3 and a shaft portion 24 formed on the output shaft 16 on the side of the case body 2 so as to be rotatably supported by a recess 26 formed on the case body 2. Yes. A fourth gear 17 is integrally formed on the output shaft 16 adjacent to the bearing 18. The fourth gear 17 meshes with the third gear 14 and the rotation of the motor shaft 10 is transmitted, so that the output shaft 16 formed integrally with the fourth gear 17 rotates according to the rotation of the motor shaft 10.
[0015]
As shown in FIG. 3, the length L1 from the axial end surface of the first gear 11 on the extension 15 side to the tip of the extension 15 and the depth of the recess 26 of the case body 2, that is, an opening from the recess bottom 20. As for the relationship with the distance L2 to the portion 27, the length L1 of the extension 15 and the distance L2 of the recess 26 are set so that L1> L2.
[0016]
Next, the effect | action of this Embodiment is demonstrated based on FIG. The motor 5 is assembled in the direction of arrow B from the extension portion 15 side of the motor shaft 10 on the distal end side to the motor housing portion 9 of the case body 2. When assembled, the length L1 from the bottom surface 20 of the recess to the tip of the extension 15 is longer than the distance L2 from the opening 27, so that the extension 15 side of the first gear 11 reaches the opening 27 of the recess 26. Before doing so, the tip of the extension 15 reaches the bottom surface 20 of the recess. Therefore, even when the motor 5 is assembled to the motor housing 9 with a gap between the motor 5 and the inner wall of the motor housing 9, the axial end surface on the extension 15 side of the first gear 11 is Before reaching the opening 27, the tip of the extension 15 reaches the bottom surface 20 of the recess. This prevents the first gear 11 from coming into contact with the opening 27 of the recess 26 during assembly.
[0017]
Furthermore, after the distal end portion 13 of the extension portion 15 reaches the recess bottom surface 20, the distal end portion 13 of the extension portion 15 is inserted into the shaft hole 21 as a guide portion formed on the recess bottom surface 20, thereby allowing the case main body 2. The position of the motor 5 on the extension 15 side is substantially determined. Therefore, after the extension portion 15 is inserted into the shaft hole 21, the first gear 11 is also accommodated in a state where the first gear 11 is substantially positioned with respect to the concave portion 26 of the case body 2. There is no contact with the recess 26 and the opening 27 thereof, and there is no deformation of the first gear 11 due to contact. Therefore, even when the first gear 11 meshes with the second gear 12 and rotates to transmit power, abnormal noise due to the deformation of the first gear 11 is eliminated.
[0018]
Moreover, since the front-end | tip part 13 of the extension part 15 is supported by the support part 32 formed in the cover body 3, even when a force is applied to a motor shaft and it bends, the bending can be suppressed reliably. Vibration and noise due to the shake of the motor shaft 10 can be suppressed.
[0019]
Therefore, as in this embodiment, the length L1 of the extension 15 formed on the motor shaft 10 of the motor 5 is longer than the distance L2 from the bottom surface 20 of the recess to the opening 27. Before the first gear 11 reaches the opening 27, the distal end portion 13 of the extension portion 15 reaches the recess bottom surface 20, and then is inserted into the shaft hole 21 to ensure that the motor shaft 10 and the first gear 11 are guided. As a result, the first gear 11 does not come into contact with the opening 27.
[0020]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to improve the assembling property and the quality of the parts after assembling without increasing the number of parts.
[Brief description of the drawings]
FIG. 1 is a front view of an actuator according to an embodiment.
FIG. 2 is a cross-sectional view taken along the line AA of FIG.
FIG. 3 is a cross-sectional view showing a state where the motor 5 is assembled to the case main body in the direction of arrow B.
FIG. 4 is a cross-sectional view of a conventional actuator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Actuator, 2 ... Case main body, 3 ... Cover body, 4 ... Cover, 5 ... Motor, 9 ... Motor accommodating part (accommodating part), 10 ... Motor shaft 11 ... first gear, 13 ... tip, 15 ... extension part, 20 ... concave bottom, 21 ... shaft hole (guide part), 26 ... concave, 27 ... .Opening part, 32 ... support part

Claims (3)

A motor having a motor shaft with gears attached thereto;
An actuator including a housing portion of the motor and a recess that is continuous with the housing portion and houses a gear, and a case main body to which the motor is assembled from one axial end side of the motor shaft,
A gap is formed between the motor and the inner wall of the housing portion,
The actuator is characterized in that an extension portion is formed on the motor shaft so as to extend from the axial end surface of the gear to the opposite side of the motor, and the extension portion is formed longer than the axial height of the recess. 2. The actuator according to claim 1, wherein a guide portion of the extension portion is formed in the recess. 3. The actuator according to claim 1, wherein a support portion that supports a distal end portion of the extension portion is disposed in the case main body.

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