Gearbox of gear motor assembly

Patent metadata

Field	Value
Publication number	US-10138994-B2
Application number	US-201514970064-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Dec 16, 2014
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

A gearbox for a gear motor assembly has a housing defining a chamber and an opening in communication with the chamber. A stationary shaft has one end mounted to a bottom of the chamber and the other end extends toward the opening. A worm wheel is rotatably mounted on the stationary shaft and disposed in the chamber. An output gear connected to the worm wheel protrudes out of the chamber. A cover seals the opening of the chamber. The cover has an annular cover plate with an inner bore and an inner flange extending from an edge of the inner bore towards the bottom of the chamber. The worm wheel has a cylindrical boss that is supported by the inner flange against lateral movement.

First claim

The invention claimed is:

1. A gearbox comprising:
a housing defining a chamber and an opening in communication with the chamber;
a stationary shaft having one end mounted to a bottom of the chamber and the other end extending through the opening;
a worm wheel rotatably mounted to the stationary shaft, and disposed in the chamber;
an output gear coaxially connected to the worm wheel for rotation with the worm wheel, the output gear protruding out of the opening;
a cover mounted to the opening;
wherein the cover is formed from a single type of material and includes an annular cover plate having an inner bore, an inner flange extending from an edge of the inner bore towards the bottom of the chamber, and an outer flange extending from an outer circumferential edge of the cover plate into the housing for positioning the cover; and
the worm wheel includes a cylindrical boss on a side adjacent the output gear, the cylindrical boss of the worm wheel extends into the inner bore of the annular cover plate and directly contacts the inner flange, and the worm wheel and the cylindrical boss are monolithically formed.

2. The gearbox of claim 1 , wherein a height of the inner flange is greater than a height of the outer flange.

3. The gearbox of claim 1 , wherein the outer flange defines at least one cutout, and the housing includes at least one corresponding protrusion engaging with the cutout for positioning of the cover.

4. The gearbox of claim 1 , wherein the cover further includes a plurality of reinforcement ribs interconnecting a radially outer surface of the inner flange and the cover plate.

5. The gearbox of claim 4 , wherein the reinforcement ribs are each plate-shaped, and a height of the reinforcement ribs gradually decrease in a direction away from the inner flange.

6. The gearbox of claim 1 , wherein a first O-ring is disposed between a distal end of the inner flange and the worm wheel and radially surrounds the stationary shaft.

7. The gearbox of claim 6 , wherein the output gear is inserted into the cylindrical boss, and a second O-ring is disposed between the output gear and the worm wheel and seals the worm wheel to the stationary shaft.

8. The gearbox of claim 1 , wherein a radially inner surface of the inner flange is provided with a plurality of grooves for receiving lubricant.

9. The gearbox of claim 1 , wherein the output gear is formed from metal, the worm wheel is formed with the output gear by an insert molding process, and the cover is formed from a plastic material.

10. The gearbox of claim 1 , wherein the cover seals the opening in the housing.

11. A gear motor assembly comprising:
a motor including an output shaft and a worm provided on the output shaft; and
a gearbox, the gearbox comprising:
a housing defining a chamber and an opening in communication with the chamber;
a stationary shaft having one end mounted to a bottom of the chamber and the other end extending through the opening;
a worm wheel rotatably mounted to the stationary shaft, and disposed in the chamber;
an output gear coaxially connected to the worm wheel for rotation with the worm wheel, the output gear protruding out of the opening; and
a cover mounted to the opening,
wherein the cover is formed from a single type of material and includes an annular cover plate having an inner bore, an inner flange extending from an edge of the inner bore towards the bottom of the chamber, and an outer flange extending from an outer circumferential edge of the cover plate into the housing for positioning the cover; and
the worm wheel includes a cylindrical boss on a side adjacent the output gear, the boss of the worm wheel extending into the inner bore of the annular cover plate and directly contacts the inner flange, and the worm wheel and the cylindrical boss are monolithically formed; and
the worm extends into the chamber and is in mesh with the worm wheel.

12. The motor assembly of claim 11 , wherein a height of the inner flange is greater than a height of the outer flange.

13. The motor assembly of claim 11 , wherein the outer flange defines at least one cutout, and the housing includes at least one corresponding protrusion engaging with the cutout for positioning of the cover.

14. The motor assembly of claim 11 , wherein the cover further includes a plurality of reinforcement ribs interconnecting a radially outer surface of the inner flange and the cover plate.

15. The motor assembly of claim 11 , wherein a first O-ring is disposed between a distal end of the inner flange and the worm wheel and radially surrounds the stationary shaft.

16. The motor assembly of claim 15 , wherein the output gear is inserted into the cylindrical boss, and a second O-ring is disposed between the output gear and the worm wheel and seals the worm wheel to the stationary shaft.

17. The motor assembly of claim 11 , wherein a radially inner surface of the inner flange is provided with a plurality of grooves for receiving lubricant.

18. The motor assembly of claim 11 , wherein the cover seals the opening in the housing.

Assignees

• Johnson Electric Sa

Inventors

• Mao Wei Xing
• Ouyang Fan
• Yue Xiao Liang
• Yan Long
• Liu Chuan

Classifications

• F16H1/16 Primary

  comprising worm and worm-wheel · CPC title

• F16H55/24

  Special devices for taking up backlash · CPC title

• F16H57/03

  characterised by means for reinforcing gearboxes, e.g. ribs · CPC title

• F16H57/0424

  Lubricant guiding means in the wall of or integrated with the casing, e.g. grooves, channels, holes · CPC title

• F16H57/039 Primary

  Gearboxes for accommodating worm gears · CPC title