Gearhead and handheld power tool

Patent metadata

Field	Value
Publication number	US-11167388-B2
Application number	US-201916453450-A
Country	US
Kind code	B2
Filing date	Jun 26, 2019
Priority date	Jun 26, 2018
Publication date	Nov 9, 2021
Grant date	Nov 9, 2021

Abstract

A gearhead for a handheld power tool for machining workpieces, having a housing in which an output that can be connected to a drive of a handheld power tool is accommodated, and also having a tool shaft to which a tool can be coupled, wherein a braking device that can be moved between a braking position and a release position and that acts upon the tool shaft is provided for braking of the tool shaft. A switching device is provided that can be moved between a first switching position, in which the tool shaft is connected to the output in a power transmitting manner and in which the braking device is transferred into the release position, and a second switching position, in which the tool shaft is decoupled from the output and in which the braking device is transferred into the braking position.

First claim

What is claimed is:

1. A gearhead for a handheld power tool for machining workpieces, the gearhead comprising:
a housing in which an output connectable to a drive of the hand-held power tool is accommodated;
a tool shaft to which a tool is adapted to be coupled;
a braking device movable between a braking position and a release position and that acts upon the tool shaft for braking the tool shaft; and
a switching device movable between a first switching position, in which the tool shaft is connected to the output in a power transmitting manner and in which the braking device is transferred into the release position, and a second switching position, in which the tool shaft is decoupled from the output and in which the braking device is transferred into the braking position,
wherein the switching device includes at least one radially movable switch, which is accommodated in a control cam that is formed on a freewheel inner ring and that is delimited by a first seat defining the first switching position and a second seat defining the second switching position.

2. The gearhead according to claim 1 , wherein the switching device interacts with the output such that the switching device is moved between the first switching position and the second switching position by a mechanical switching impulse induced by the output.

3. The gearhead according to claim 1 , wherein the at least one radially movable switch located in the first seat in the first switching position is frictionally connected to the output.

4. The gearhead according to claim 1 , wherein the switching device includes a switching ring that surrounds the freewheel inner ring and that has, on an outer circumferential side, at least one radial opening that provides a retaining function for the at least one radially movable switch, wherein the at least one radially movable switch passes radially through the at least one radial opening in the first switching position.

5. The gearhead according to claim 4 , wherein a radially inward-pointing overlap section is associated with the switching ring.

6. A gearhead for a handheld power tool for machining workpieces, the gearhead comprising:
a housing in which an output connectable to a drive of the handheld power tool is accommodated;
a tool shaft to which a tool is adapted to be coupled;
a braking device movable between a braking position and a release position and that acts upon the tool shaft for braking the tool shaft; and
a switching device movable between a first switching position, in which the tool shaft is connected to the output in a power transmitting manner and in which the braking device is transferred into the release position, and a second switching position, in which the tool shaft is decoupled from the output and in which the braking device is transferred into the braking position,
wherein the braking device includes a brake sleeve that is connected to the tool shaft in a rotationally fixed manner and that is moved axially relative to the tool shaft between the release position and the braking position.

7. The gearhead according to claim 6 , wherein a return element is provided that exerts a restoring force on the brake sleeve in the release position of the braking device.

8. The gearhead according to claim 1 , wherein the switching device has a cam mechanism for moving the braking device between the release position and the braking position.

9. The gearhead according to claim 8 , wherein the braking device includes a brake sleeve that is connected to the tool shaft in a rotationally fixed manner and that is moved axially relative to the tool shaft between the release position and the braking position, and wherein the cam mechanism includes at least one axial drive cam formed on the freewheel inner ring for interacting with a mating cam formed on the brake sleeve.

10. The gearhead according to claim 6 , wherein the braking device has a braking surface associated with the housing and an opposite surface associated with the brake sleeve for interacting with the braking surface.

11. The gearhead according to claim 10 , wherein the braking surface is arranged on a brake ring that is connected to the housing in a rotationally fixed manner.

12. The gearhead according to claim 6 , wherein a spacer sleeve forming an axial guide for the brake sleeve is provided that is connected in a rotationally fixed and axially immovable manner to the tool shaft.

13. The gearhead according to claim 1 , wherein the output includes a transmission having a bevel-gear drive and a bevel gear.

14. A handheld power tool comprising a drive and also having a gearhead according to claim 1 .

15. The gearhead according to claim 5 , wherein the radially inward-pointing overlap section is an annular shoulder.

Assignees

• Fein C & E Gmbh

Inventors

• Duernegger Wolfgang

Classifications

• B25F5/02

  Construction of casings, bodies or handles {(B25F5/006, B25F5/008 take precedence)} · CPC title

• B24B47/12

  by mechanical gearing or electric power (B24B47/16 takes precedence) · CPC title

• B25F5/00 Primary

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title

• B24B23/02 Primary

  with rotating grinding tools; Accessories therefor · CPC title

• B24B41/04

  Headstocks; Working-spindles; Features relating thereto · CPC title