Rotary power tool including transmission housing bushing

Patent metadata

Field	Value
Publication number	US-11148273-B2
Application number	US-201916360585-A
Country	US
Kind code	B2
Filing date	Mar 21, 2019
Priority date	Mar 30, 2018
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

A rotary power tool comprises a drive mechanism including an electric motor and a transmission, a housing enclosing at least a portion of the drive mechanism, a spindle rotatable in response to receiving torque from the drive mechanism, a first ratchet coupled for co-rotation with the spindle, a second ratchet rotationally fixed to the housing, a sleeve bushing on an interior of the housing, and a bearing arranged between the spindle and the sleeve bushing and rotatably supporting the spindle. The bearing has an outer race. The spindle is movable relative to the housing in response to contact with a workpiece, causing the first and second ratchets to engage and the spindle to reciprocate while rotating. The outer race of the bearing moves along the sleeve bushing during reciprocation of the spindle when the first ratchet and second ratchet are engaged.

First claim

What is claimed is:

1. A rotary power tool comprising:
a drive mechanism including an electric motor and a transmission;
a housing enclosing at least a portion of the drive mechanism, the housing including an annular portion;
a spindle rotatable in response to receiving torque from the drive mechanism;
a first ratchet coupled for co-rotation with the spindle;
a second ratchet rotationally fixed to the housing;
a sleeve bushing on an inner surface of the annular portion of the housing; and
a bearing arranged between the spindle and the sleeve bushing and rotatably supporting the spindle, the bearing having an outer race,
wherein the spindle is movable relative to the annular portion of the housing in response to contact with a workpiece, causing the first and second ratchets to engage and the spindle to reciprocate while rotating,
wherein the outer race of the bearing moves along the sleeve bushing during reciprocation of the spindle when the first ratchet and second ratchet are engaged, and
wherein the first ratchet and the bearing are set within a cylindrical cavity defined within the annular portion of the transmission housing.

2. The rotary power tool of claim 1 , wherein the sleeve bushing terminates short of a distal end of the annular portion.

3. The rotary power tool of claim 2 , wherein the housing is at least partially formed of aluminum.

4. The rotary power tool of claim 1 , wherein the sleeve bushing is insert molded with the housing.

5. The rotary power tool of claim 1 , wherein the sleeve bushing is press fit with the housing.

6. The rotary power tool of claim 1 , wherein the sleeve bushing is shrink fit with the housing.

7. The rotary power tool of claim 1 , further comprising a hammer lockout mechanism adjustable between a first mode and a second mode, the hammer lockout mechanism including an aperture in the housing and a detent movable within the aperture between a locking position and an unlocking position,
wherein, in the first mode, the detent is moveable from the locking position to the unlocking position, such that the spindle is movable relative to the housing in response to contact with a workpiece, causing the first and second ratchets to engage, and
wherein, in the second mode, the detent is prevented from moving from the locking position to the unlocking position, such that the spindle is blocked by the detent from moving relative to the housing in response to contact with a workpiece and a gap is maintained between the first and second ratchets.

8. The rotary power tool of claim 7 , wherein the aperture extends through the sleeve bushing.

9. The rotary power tool of claim 7 , wherein the housing includes a radially inward-extending protrusion extending through the sleeve bushing, and wherein the aperture extends through the protrusion.

10. The rotary power tool of claim 9 , wherein the sleeve bushing is formed of a first material and the housing is formed of second material that is softer than the first material.

11. The rotary power tool of claim 7 , wherein the bushing is arranged in front of the aperture, such that no portion of the bushing intersects the aperture.

12. A rotary power tool comprising:
a drive mechanism including an electric motor and a transmission;
a housing enclosing at least a portion of the drive mechanism and including a protrusion;
a spindle rotatable in response to receiving torque from the drive mechanism;
a first ratchet coupled for co-rotation with the spindle;
a second ratchet rotationally fixed to the housing;
a sleeve bushing on an interior of the housing, the protrusion of the housing extending through the sleeve bushing;
a bearing arranged between the spindle and the sleeve bushing and rotatably supporting the spindle, the bearing having an outer race; and
a hammer lockout mechanism adjustable between a first mode and a second mode, the hammer lockout mechanism including
an aperture extending through the protrusion, and
a ball movable within the aperture between a locking position and an unlocking position,

wherein, in the first mode, the ball is moveable from the locking position to the unlocking position, such that the spindle is movable relative to the housing in response to contact with a workpiece, causing the first and second ratchets to engage and the spindle to reciprocate while rotating,
wherein the outer race of the bearing moves along the sleeve bushing during reciprocation of the spindle when the first ratchet and second ratchet are engaged, and
wherein, in the second mode, the ball is prevented from moving from the locking position to the unlocking position, such that the spindle is blocked by the ball from moving relative to the housing in response to contact with a workpiece and a gap is maintained between the first and second ratchets.

13. The rotary power tool of claim 12 , wherein the sleeve bushing formed of steel.

14. The rotary power tool of claim 13 , wherein the housing is at least partially formed of aluminum.

15. The rotary power tool of claim 12 , wherein the sleeve bushing is insert molded with the housing.

16. The rotary power tool of claim 12 , wherein the sleeve bushing is press fit with the housing.

17. The rotary power tool of claim 12 , wherein the sleeve bushing is formed of a first material and the housing is formed of second material that is softer than the first material, and wherein the aperture in the housing is defined by the second material.

18. A rotary power tool comprising:
a drive mechanism including an electric motor and a transmission;
a housing enclosing at least a portion of the drive mechanism and including a plurality of protrusions;
a spindle rotatable in response to receiving torque from the drive mechanism;
a first ratchet coupled for co-rotation with the spindle;
a second ratchet rotationally fixed to the housing;
a sleeve bushing on an interior of the housing, the protrusions of the housing extending through the sleeve bushing;
a bearing arranged between the spindle and the sleeve bushing and rotatably supporting the spindle, the bearing having an outer race; and
a hammer lockout mechanism adjustable between a first mode and a second mode, the hammer lockout mechanism including
a plurality of apertures, each aperture extending through one of the plurality of protrusions, and
a ball arranged in each aperture, each ball moveable between a locking position and an unlocking position,

wherein, in the first mode, each of the balls is moveable from the locking position to the unlocking position, such that the spindle is movable relative to the housing in response to contact with a workpiece, causing the first and second ratchets to engage and the spindle to reciprocate while rotating,
wherein the outer race of the bearing moves along the sleeve bushing during reciprocation of the spindle when the first ratchet and second ratchet are engaged, and
wherein, in the second mode, at least one of the balls is prevented from moving from the locking position to the unlocking position, such that the spindle is blocked by one or more balls from moving relative to the housing in response to contact with a workpiece and a gap is maintained between the first and second ratchets.

19. The rotary power tool of claim 18 , wherein the sleeve bushing is insert molded with the housing.

20. The rotary power tool of claim 18 , wherein the sleeve bushing is press fit with the housing.

21. The rotary power tool of claim 18 , wherein the sleeve bushing is forme

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Dedrickson Ryan A
• Duncan Ian Allen
• Yu Tian
• Li jian wei

Classifications

• B25D2250/335

  Supports therefor · CPC title

• B25D2250/321

  Use of balls · CPC title

• B25D16/003

  Clutches specially adapted therefor · CPC title

• B25D2250/165

  Overload clutches, torque limiters · CPC title

• B25D11/106 Primary

  cam member and cam follower having the same shape (B25D11/104 takes precedence) · CPC title