A device for sensing a direction of rotation of a hand tool having an electric motor, has a rotatably supported brush plate provided in the electric motor and located in different positions depending on a direction of rotation of the electric motor; and at least one sensor which senses the different positions of said brush plate to determine a direction of rotation, wherein said sensor is configured as a contactless sensor.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an electrical machine with the inventive device, and
FIG. 2 shows a detailed view of the inventive device.
Claims
1. A device for sensing a direction of rotation of a hand tool having an electric motor, the device comprising a rotatably supported brush plate provided in the electric motor and located in different positions depending on a direction of rotation of the electric motor; and at least one sensor which senses the different positions of said brush plate to determine a direction of rotation, said sensor being configured as a contactless sensor.
2. A device as defined in claim 1, wherein said sensor is configured so that said sensor is switched by a magnetic field which acts on it.
3. A device as defined in claim 1, wherein said sensor is configured as a Hall sensor.
4. A device as defined in claim 1, wherein said sensor is configured as a reed relay.
5. A device as defined in claim 1; and further comprising an electronics module, said sensor being located in said electronic module.
6. A device as defined in claim 5, wherein said electronic module is located outside the electric motor and inside the hand tool.
7. A device as defined in claim 1; and further comprising at least one magnet assigned to said rotatably supported brush plate.
8. A device as defined in claim 7; and further comprising a lever which is actuated by said brush plate, said magnet being located on said lever.
9. A device as defined in claim 7, wherein said magnet is configured so that it is activated in only one direction of rotation of the electric motor by a position of said brush plate.
10. A device as defined in claim 8, wherein said magnet is configured so that it is activated in only one direction of rotation of the electric motor by a position of said lever.
11. A device as defined in claim 1; and further comprising means for displaying the direction of rotation which was sensed, to a user via at least one visual signal.
12. A device as defined in claim 1; and further comprising means for displaying the direction of rotation which was sensed, to a user via at least one acoustic signal.
13. A device as defined in claim 7, wherein said at least one magnet assigned to said rotatably supported brush plate is configured as a permanent magnet.
14. An electric hand tool, comprising an electric motor; said electric motor including a rotatably supported brush plate which is located in different position depending on a direction of rotation of said electric motor; at least one sensor which senses the different positions of said rotatably supported brush plate to determine a direction of rotation, said at least one sensor being configured as a contactless sensor.
15. An electric hand tool as defined in claim 14, wherein said electric hand tool is a rotary hammer.
16. An electric hand tool as defined in claim 14, wherein said electric hand tool is an impact drill.
Patent Application
20070152660
