Power tool with knurled bushing
A power tool includes a housing, a drive assembly including an output shaft extending from the housing such that a tool element for performing work on a workpiece is attachable to the output shaft, and a bushing rotatably supporting the output shaft. The bushing includes an outer surface having a knurled texture.
1. A power tool comprising:
a housing;
a drive assembly including an output shaft extending from the housing such that a tool element for performing work on a workpiece is attachable to the output shaft; and
a bushing rotatably supporting the output shaft,
wherein the bushing includes an outer surface having a knurled texture, the knurled texture including a plurality of teeth spaced apart along a length and a circumference of the outer surface such that the knurled texture provides a strong connection between the bushing and the housing to resist axial forces on the bushing, and
wherein the bushing is insert-molded within the housing.
2. The power tool of claim 1 , wherein the housing includes a motor housing portion and a gear case coupled to the motor housing portion, and wherein the power tool further comprises a motor supported within the motor housing portion and a gear assembly supported within the gear case.
3. The power tool of claim 2 , wherein the gear case includes a nose at a front end portion of the gear case, and wherein the output shaft extends through a bore in the nose.
4. The power tool of claim 3 , wherein the bushing is positioned within the bore.
5. The power tool of claim 4 , wherein the bore includes a corresponding knurled texture formed by insert molding the bushing within the gear case.
6. The power tool of claim 3 , further comprising a light assembly surrounding the nose.
7. The power tool of claim 6 , wherein the light assembly is supported by a holder coupled to the nose, wherein the nose includes a groove, and wherein a retaining ring is received in the groove to retain the holder on the nose.
8. The power tool of claim 2 , wherein the output shaft is an anvil, and wherein the drive assembly further includes a camshaft and a hammer configured to impart consecutive rotational impacts upon the anvil in response to rotation of the camshaft.
9. The power tool of claim 8 , wherein the anvil engages a rear end of the bushing such that the bushing both rotationally and axially supports the anvil.
10. The power tool of claim 2 , wherein the bushing and the gear case are made of different materials.
11. The power tool of claim 10 , wherein the bushing is made of AISI 4140 or AISI 52100 steel, and wherein the gear case is made of A380 aluminum.
12. The power tool of claim 1 , wherein each tooth of the knurled texture has the shape of a rectangular pyramid.
13. The power tool of claim 12 , wherein each tooth has a height between 0.3 millimeters and 0.7 millimeters.
14. A power tool comprising:
a housing including a motor housing portion and a gear case coupled to the motor housing portion;
a motor supported within the motor housing portion;
a gear assembly supported within the gear case and driven by the motor;
a drive assembly driven by the gear assembly, the drive assembly including an anvil extending from the gear case, a camshaft driven by the gear assembly, and a hammer configured to impart consecutive rotational impacts upon the anvil in response to rotation of the camshaft; and
a bushing insert-molded within the gear case, the bushing rotatably and axially supporting the anvil,
wherein the bushing includes an outer surface and a plurality of teeth spaced apart along a length and a circumference of the outer surface to resist axial forces on the bushing.
15. The power tool of claim 14 , wherein the plurality of teeth defines a knurled texture.
16. The power tool of claim 15 , wherein the knurled texture comprises a plurality of teeth, each tooth having a height between 0.3 millimeters and 0.7 millimeters.
17. The power tool of claim 15 , wherein the housing includes a handle housing portion extending from the motor housing portion, and wherein the handle housing portion includes a battery receptacle configured to receive a battery for powering the motor.
18. The power tool of claim 14 , wherein the bushing includes a cylindrical inner surface rotatably supporting the anvil and a groove formed in the inner surface, the groove retaining a lubricant.
19. A power tool comprising:
a housing including a motor housing portion and a gear case coupled to the motor housing portion;
a motor supported within the motor housing portion;
a gear assembly supported within the gear case and driven by the motor;
a drive assembly driven by the gear assembly, the drive assembly including an output shaft extending from the gear case; and
a knurled bushing fixed within the gear case, the knurled bushing rotatably and axially supporting the output shaft,
wherein the knurled bushing includes a plurality of teeth spaced apart along a length and a circumference of an outer surface of the bushing such that the plurality of teeth provides a strong connection between the bushing and the housing to resist axial forces on the bushing.