Angle grinder comprising a yaw rate sensor for measuring the housing rotation

Patent metadata

Field	Value
Publication number	US-9962807-B2
Application number	US-201113642177-A
Country	US
Kind code	B2
Filing date	Feb 25, 2011
Priority date	Apr 20, 2010
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

An angle grinder includes a housing, a drive unit configured to drive a usage tool, a sensor device configured to provide a rotation parameter, and a control unit configured to evaluate the rotation parameter to detect a clamped state of the usage tool. The sensor device has a yaw rate sensor configured to provide the rotation parameter in accordance with a rotational movement of the housing. The control unit triggers a safety mode in accordance with the rotation parameter or throttles the rotational speed and/or torque of the drive unit.

First claim

The invention claimed is:

1. An angle grinder, comprising:
a drive unit configured to drive an insertion tool;
an angle grinder housing in which the drive unit is arranged;
a sensor device arranged in the angle grinder housing and including a yaw rate sensor configured to detect a yaw rate of the angle grinder housing and provide a rotation parameter as a function of the detected yaw rate; and
a control and/or regulating unit configured to evaluate the rotation parameter and to detect a jammed state of the insertion tool based on the rotation parameter.

2. The angle grinder as claimed in claim 1 , wherein the yaw rate sensor is configured to provide the rotation parameter independently of an acceleration of a rotational movement of the angle grinder housing.

3. The angle grinder as claimed in claim 1 , wherein the control and/or regulating unit is configured to trigger a safety mode as a function of the rotation parameter provided by the yaw rate sensor.

4. The angle grinder as claimed in claim 3 , wherein the control and/or regulating unit is configured to trigger the safety mode only beginning at a defined value of the rotation parameter.

5. The angle grinder as claimed in claim 3 , wherein one or more of a rotational speed and a torque of the drive unit is throttled very highly in the safety mode.

6. The angle grinder as claimed in claim 1 , wherein the yaw rate sensor is configured to detect the yaw rate of the angle grinder housing about a sensitive axis oriented substantially coaxially with respect to a main axis of rotation of the insertion tool.

7. The angle grinder as claimed in claim 1 , wherein the yaw rate sensor detects the yaw rate of the angle grinder housing irrespective of a position of the yaw rate sensor in the angle grinder housing.

8. The angle grinder as claimed in claim 1 , wherein the drive unit is an unregulated drive unit.

9. The angle grinder as claimed in claim 1 , wherein the control and/or regulating unit is configured to trigger a safety mode beginning at a rotation parameter of 100 to 500 degrees per second.

Assignees

• Klee Christoph
• Faisst Hans Joerg
• Bosch Gmbh Robert

Inventors

• Klee Christoph
• Faisst Hans-Joerg

Classifications

• B24B23/028

  Angle tools · CPC title

• B23Q11/0085

  by determining whether the machine tool is in a dangerous configuration · CPC title

• B24B49/10

  involving electrical means (B24B49/02, B24B49/08 take precedence) · CPC title

• B24B49/006 Primary

  taking regard of the speed · CPC title

• F16P5/00

  Emergency means for rendering ineffective a coupling conveying reciprocating movement if the motion of the driven part is prematurely resisted · CPC title