Motor device

Patent metadata

Field	Value
Publication number	US-9859771-B2
Application number	US-201414650385-A
Country	US
Kind code	B2
Filing date	Feb 28, 2014
Priority date	Feb 28, 2013
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A motor device may include a motor including a motor shaft protruded from a motor main body; a worm gear connected with the motor shaft through a transmission mechanism and is formed with a spiral groove; and a worm wheel engaged with the worm gear. The transmission mechanism may include a transmission member to transmit rotation of the motor shaft to the worm gear. One end face on the motor main body side of the worm gear and an end face on a worm gear side of the transmission member may be formed with two protruded parts protruded toward the other of the end faces, and a recessed part engaged with the protruded parts is formed in the other of the end faces. A compression coil spring may disposed between the worm gear and the transmission member between the two protruded parts.

First claim

The invention claimed is:

1. A motor device comprising:
a motor comprising a motor shaft protruded from a motor main body;
a worm gear which is connected with the motor shaft through a transmission mechanism and is formed with a spiral groove on an outer peripheral face; and
a worm wheel which is engaged with the worm gear;
wherein the transmission mechanism comprises a transmission member structured to transmit rotation of the motor shaft to the worm gear at a position facing an end face on a motor main body side of the worm gear in an axial line direction of the worm gear;
wherein one of the end face on the motor main body side of the worm gear and an end face on a worm gear side of the transmission member is formed with two protruded parts which are protruded toward the other of the end faces at positions separated in a radial direction, and a recessed part engaged with the protruded parts is formed in the other of the end faces; and
wherein a compression coil spring is disposed between the worm gear and the transmission member so that the compression coil spring is disposed between the two protruded parts;
a spring arrangement hole which is extended from the end face on the motor main body side of the worm gear in the axial line direction of the worm gear is formed in an inside of the worm gear, and
the compression coil spring is disposed in the inside of the spring arrangement hole;
the spring arrangement hole is coaxially formed with the worm gear;
the worm gear is made of resin,
the inside of the worm gear is formed with a communicating hole which is in communication with the spring arrangement hole and is extended in the axial line direction on an opposite side to the motor main body side with respect to the spring arrangement hole, and
an inner diameter of the communicating hole is smaller than an inner diameter of the spring arrangement hole.

2. The motor device according to claim 1 , wherein a sum of a dimension in the axial line direction of the spring arrangement hole and a dimension in the axial line direction of the communicating hole is longer than a dimension in the axial line direction of the compression coil spring.

3. The motor device according to claim 1 , wherein
a ring-shaped step part which is formed in a connected portion of the spring arrangement hole with the communicating hole is formed to be a spring receiving face which receives an end part of the compression coil spring on an opposite side to the motor main body side, and
a width in a radial direction of the spring receiving face is wider than a difference between a diameter of the compression coil spring and an inner diameter of the spring arrangement hole.

4. The motor device according to claim 1 , wherein when the worm gear is viewed in the radial direction, a part of the spring arrangement hole is overlapped with a range where the spiral groove and the worm wheel are engaged with each other.

5. The motor device according to claim 1 , wherein when the worm gear is viewed in the radial direction, the spring receiving face is located on the motor main body side relative to a range where the spiral groove and the worm wheel are engaged with each other.

6. The motor device according to claim 1 , further comprising a side pressure application mechanism structured to press the worm gear toward an opposite side to a side where the worm wheel is located.

7. The motor device according to claim 6 , wherein the side pressure application mechanism is provided at an end part of the worm gear on an opposite side to the motor main body side.

8. The motor device according to claim 7 , wherein the side pressure application mechanism comprises a thrust bearing which is obliquely inclined with respect to the axial line direction and supports the end part of the worm gear on the opposite side to the motor main body side.

9. The motor device according to claim 1 , further comprising:
two motor side radial bearings which rotatably support the motor shaft in the motor main body; and
two worm gear side radial bearings which rotatably support the worm gear.

10. The motor device according to claim 1 , further comprising:
two motor side radial bearings which rotatably support the motor shaft in the motor main body; and
two worm gear side radial bearings which rotatably support the worm gear;
wherein when the worm gear is viewed in the radial direction, the worm gear side radial bearing located on the motor main body side of the two worm gear side radial bearings is provided at a position overlapping with the spring arrangement hole.

11. The motor device according to claim 9 , wherein the worm gear side radial bearing located on the motor main body side of the two worm gear side radial bearings is further separated from a region where the spiral groove and the worm wheel are engaged with each other, compared with the worm gear side radial bearing located on an opposite side to the motor main body side.

12. A motor device comprising:
a motor comprising a motor shaft protruded from a motor main body;
a worm gear which is connected with the motor shaft through a transmission mechanism and is formed with a spiral groove on an outer peripheral face;
a worm wheel which is engaged with the worm gear; and
a side pressure application mechanism structured to press the worm gear toward an opposite side to a side where the worm wheel is located
wherein the transmission mechanism comprises a transmission member structured to transmit rotation of the motor shaft to the worm gear at a position facing an end face on a motor main body side of the worm gear in an axial line direction of the worm gear;
wherein one of the end face on the motor main body side of the worm gear and an end face on a worm gear side of the transmission member is formed with two protruded parts which are protruded toward the other of the end faces at positions separated in a radial direction, and a recessed part engaged with the protruded parts is formed in the other of the end faces; and
wherein a compression coil spring is disposed between the worm gear and the transmission member so that the compression coil spring is disposed between the two protruded parts;
wherein the side pressure application mechanism is provided at an end part of the worm gear on an opposite side to the motor main body side;
wherein the side pressure application mechanism comprises a thrust bearing which is obliquely inclined with respect to the axial line direction and supports the end part of the worm gear on the opposite side to the motor main body side.

Assignees

• Nidec Sankyo Corp

Inventors

• Yamaoka Mamoru
• Ogawa Yoshinori
• Kasuga Takafumi
• Shingu Yuji

Classifications

• H02K7/1166 Primary

  comprising worm and worm-wheel (structural association with bearings specially adapted for worm gear drives H02K7/081) · CPC title

• H02K7/081 Primary

  specially adapted for worm gear drives (H02K7/09 takes precedence) · CPC title

• F16D3/04

  specially adapted to allow radial displacement, e.g. Oldham couplings · CPC title

• F16H55/24

  Special devices for taking up backlash · CPC title

• F16H1/16

  comprising worm and worm-wheel · CPC title