Actuator and method for manufacturing the same
A housing accommodates a motor and a deceleration mechanism. The deceleration mechanism includes a support axis extending perpendicularly to an output shaft of the motor. The housing includes a case and a cover. The case is in a bottomed tubular shape to have an accommodation chamber and a holder portion. The holder portion surrounds a bottom of the accommodation chamber and is in contact with the motor. The cover is mounted to the case to surround an opening of the case and to form a hollow portion with the holder portion to accommodate at least the motor. The motor and the deceleration mechanism are mountable into the accommodation chamber through the opening in one direction from a side of a mounting surface of the case, on which the housing is to be affixed to a support portion of an affixing member.
1. An actuator comprising:
a motor configured to generate an output power;
a deceleration mechanism configured to decelerate rotation of the motor; and
a housing accommodating the motor and the deceleration mechanism, wherein
the housing is configured to be screwed to and affixed to a support portion of an affixing member,
the deceleration mechanism includes a support axis extending in a direction, which is perpendicular to an axial direction of an output shaft of the motor,
the housing includes a case and a cover,
the case is in a bottomed tubular shape and has an opening, an accommodation chamber, and a holder portion,
the opening opens in a radial direction of the motor and in an axial direction of the support axis, the opening being configured to open on a side of the support portion,
the accommodation chamber extends from the opening toward a bottom,
the holder portion surrounds the bottom of the accommodation chamber and is in contact with the motor,
the cover is mounted to the case to surround the opening,
the cover has a biasing portion, which forms a hollow portion with the holder portion, the hollow portion accommodates at least the motor,
the motor and the deceleration mechanism are mountable to the accommodation chamber in one direction from a side of a mounting surface of the case,
the housing has the mounting surface, which is configured to be mounted to the support portion,
the actuator further comprising:
an elastic sealing member formed of an elastic material and mounted to the mounting surface, wherein
the elastic sealing member is configured to be tightly in contact with the support portion to seal a clearance between the mounting surface of the housing and the support portion,
the elastic sealing member has a projection height H 1 , before the housing is mounted to the support portion,
the cover has a projection height H 2 , before the housing is mounted to the support portion, and
the case has a projection height H 3 , before the housing is mounted to the support portion, wherein
the projection height H 1 , the projection height H 2 , and the projection height H 3 satisfy the following relation: H 1 >H 2 >H 3 .
2. The actuator according to claim 1 , wherein a mounting direction, in which the motor is mounted to the accommodation chamber is substantially the same as a mounting direction, in which the support axis is mounted to the accommodation chamber and a screwing direction, in which the housing is screwed to the support portion.
3. The actuator according to claim 1 , wherein
the deceleration mechanism includes a first gear and a second gear,
the first gear is connected with the output shaft of the motor and rotatable integrally with the output shaft,
the second gear is rotatably fitted to an outer periphery of the support axis, and
the second gear is meshed with the first gear and is rotatable.
4. The actuator according to claim 1 , wherein
the cover has an opposed end surface and a projected portion,
the opposed end surface is configured to be opposed to the support portion to form a clearance with the support portion,
the projected portion is projected from the opposed end surface and is configured to be projected toward the support portion, and
the projected portion is configured to be tightly in contact with the support portion to seal the clearance between the support portion and the opposed end surface.
5. The actuator according to claim 1 , further comprising:
an elastic member formed of an elastic material and located with the motor in the hollow portion, wherein
the elastic member is interposed between the biasing portion and the motor to elastically support the motor with the holder portion.
6. The actuator according to claim 5 , wherein the biasing portion is configured to be in contact with the motor via the elastic member to bias the motor toward the holder portion when the cover is mounted to the case to surround the opening.
7. The actuator according to claim 1 , wherein
the housing has the mounting surface configured to be mounted to the support portion,
the actuator further comprising:
a sealing member formed of an elastic material and mounted to the mounting surface of the housing, the sealing member configured to be tightly in contact with the support portion to seal a clearance between the support portion and the mounting surface of the housing; and
an elastic member formed of an elastic material and located with the motor in the hollow portion, the elastic member being interposed between the biasing portion and the motor to elastically support the motor with the holder portion.
8. The actuator according to claim 7 , wherein
the case includes a first fitting portion,
the cover includes a cover portion, an arm portion, a second fitting portion,
the cover portion surrounds the opening,
the arm portion extends from the cover portion toward the bottom of the accommodation chamber, and
the second fitting portion is equipped to the arm portion and is configured to be fitted to the first fitting portion when the cover is mounted to the case.
9. The actuator according to claim 8 , wherein the elastic member is configured to generate elasticity, in a direction in which the second fitting portion is fitted to the first fitting portion, to bias the cover relative to the motor, when the cover is mounted to the case to surround the opening and when the motor is temporary affixed.
10. The actuator according to claim 7 , wherein the elastic member is pressed between the motor and the biasing portion to generate elasticity in a direction to release fitting between the first fitting portion and the second fitting portion, when the housing is screwed to the support portion and when the motor is permanently affixed.
11. An actuator comprising:
a motor configured to generate an output power;
a deceleration mechanism configured to decelerate rotation of the motor; and
a housing accommodating the motor and the deceleration mechanism, wherein
the housing is configured to be screwed to and affixed to a support portion of an affixing member,
the deceleration mechanism includes a support axis extending in a direction, which is perpendicular to an axial direction of an output shaft of the motor,
the housing includes a case and a cover,
the case is in a bottomed tubular shape and has an opening, an accommodation chamber, and a holder portion,
the opening opens in a radial direction of the motor and in an axial direction of the support axis, the opening being configured to open on a side of the support portion,
the accommodation chamber extends from the opening toward a bottom,
the holder portion surrounds the bottom of the accommodation chamber and is in contact with the motor,
the cover is mounted to the case to surround the opening,
the cover has a biasing portion, which forms a hollow portion with the holder portion, the hollow portion accommodates at least the motor,
the motor and the deceleration mechanism are mountable to the accommodation chamber in one direction from a side of a mounting surface of the case,
the cover has an opposed end surface and a projected portion,
the opposed end surface is configured to be opposed to the support portion to form a clearance with the support portion,
the projected portion is projected from the opposed end surface and is configured to be projected toward the support portion, and
the projected portion is configured to be tightly in contact with the support portion to seal the clearance between the support portion and the opposed end surface.