Hand-held machine tool with slip clutch

1. An at least partially rotating and axially percussive hand-held machine tool having a tool receptacle for receiving a tool, comprising:

an impact mechanism ( 5 ) having a guide tube ( 6 ) in which a percussion piston ( 7 ) is driven in an axially percussive manner by a pneumatic spring ( 8 );

a driving motor ( 15 );

a slip clutch ( 10 ), encloses the guide tube ( 6 ), is provided axially with cams ( 9 ) having torque-transmitting flank surfaces ( 20 ), and has a driving sleeve ( 11 ) and a driven sleeve ( 12 ) which are biased axially towards one another under pressure by a spring ( 13 ), and

a control sleeve ( 14 ) which is driven in rotation by the driving motor ( 15 ) for driving the driving sleeve ( 11 ) to, thereby, drive in rotation the slip clutch ( 10 );

wherein the driving sleeve ( 11 ) is connected by positive engagement to the control sleeve ( 14 ) coaxial to the driving sleeve ( 11 ) by balls ( 18 ) which partially engage, respectively, in two control contours ( 19 a , 19 b ) of the driving sleeve ( 11 ) and of the control sleeve ( 14 ), which control contours ( 19 a , 19 b ) are arranged partially opposite one another,

and wherein the driving sleeve ( 11 ) is positively guided in such a way that the driving sleeve ( 11 ), which is axially biased under pressure by the spring ( 13 ), is displaced axially away from the driven sleeve ( 12 ) and rotated relative to the control sleeve ( 14 ) when a limiting torque is exceeded and then is displaced axially towards the driven sleeve ( 12 ) under action of the spring ( 13 ), whereby the driving sleeve ( 11 ) strikes the driven sleeve ( 12 ) with the torque-transmitting flank surfaces ( 20 ) so that a rotational energy of the driving sleeve ( 11 ) is transformed into a brief tangential percussion which is transmitted to the tool by the tool receptacle.

2. A hand-held machine tool according to claim 1 , wherein the first control contour ( 19 a ) is formed as a broad pocket with at least one side extending axially at an inclination, and the second control contour ( 19 b ) is formed as an elongated groove which extends at least partially at an opposite inclination axially.

3. A hand-held machine tool according to claim 2 , wherein the first control contour ( 19 a ) is formed as a triangular pocket whose apex is situated axially on the spring side and whose two sides extend, respectively, at an inclination axially, and the second control contour ( 19 b ) is formed as an elongated groove which extends axially at an opposite inclination so as to be angled in a V-shaped manner.

4. A hand-held machine tool according to claim 1 , wherein the control sleeve ( 14 ) is arranged coaxially inside the driving sleeve ( 11 ).

5. A hand-held machine tool according to claim 1 , wherein the driven sleeve ( 12 ) is connected directly to the tool receptacle ( 3 ).

6. A hand-held machine tool according to claim 1 , wherein the torque-transmitting flank surfaces ( 20 ) of the cams ( 9 ) of the driving sleeve ( 11 ) and of the driven sleeve ( 12 ) of the slip clutch ( 10 ) are exactly tangentially oriented.

7. A hand-held machine tool according to claim 1 , wherein at least two cams ( 9 ) are distributed circumferentially in a symmetric manner for the driving sleeve ( 11 ) and driven sleeve ( 12 ), respectively.

8. A hand-held machine tool according to claim 1 , further comprising a transmission gear unit ( 16 ), said transmission gear unit ( 16 ) being driven by said driving motor ( 15 ) to rotate said impact mechanism ( 5 ), wherein a second safety clutch ( 17 ) is arranged in the flow of force between the driver motor ( 15 ) and the transmission gear unit ( 16 ).

9. An at least partially rotating and axially percussive hand-held machine tool having a tool receptacle for receiving a tool, comprising:

an impact mechanism ( 5 ) having a guide tube ( 6 ) in which a percussion piston ( 7 ) is driven in an axially percussive manner by a pneumatic spring ( 8 );

a driving motor ( 15 );

a slip clutch ( 10 ), encloses the guide tube ( 6 ), is provided axially with cams ( 9 ) having torque-transmitting flank surfaces ( 20 ), and has a driving sleeve ( 11 ) and a driven sleeve ( 12 ) which are biased axially towards one another under pressure by a spring ( 13 ); and

a control sleeve ( 14 ) which is driven in rotation by the driving motor ( 15 ) for driving the driving sleeve ( 11 ) to, thereby, drive in rotation the slip clutch ( 10 );

wherein the driving sleeve ( 11 ) is positively guided in such a way that the driving sleeve ( 11 ), which is axially biased under pressure by the spring ( 13 ), is displaced axially away from the driven sleeve ( 12 ), is rotationally decoupled from the driving motor ( 15 ), and is freely rotated relative to the control sleeve ( 14 ) when a limiting torque is exceeded and then is displaced axially towards the driven sleeve ( 12 ) under action of the spring ( 13 ), whereby the driving sleeve ( 11 ) strikes the driven sleeve ( 12 ) with the torque-transmitting flank surfaces ( 20 ) so that a rotational energy of the driving sleeve ( 11 ) is transformed into a brief tangential percussion which is transmitted to the tool by the tool receptacle.

10. A hand-held machine tool according to claim 9 , wherein the first control contour ( 19 a ) is formed as a broad pocket with at least one side extending axially at an inclination, and the second control contour ( 19 b ) is formed as an elongated groove which extends at least partially at an opposite inclination axially.

11. A hand-held machine tool according to claim 10 , wherein the first control contour ( 19 a ) is formed as a triangular pocket whose apex is situated axially on the spring side and whose two sides extend, respectively, at an inclination axially, and the second control contour ( 19 b ) is formed as an elongated groove which extends axially at an opposite inclination so as to be angled in a V-shaped manner.

12. A hand-held machine tool according to claim 9 , wherein the control sleeve ( 14 ) is arranged coaxially inside the driving sleeve ( 11 ).

13. A hand-held machine tool according to claim 9 , wherein at least two cams ( 9 ) are distributed circumferentially in a symmetric manner for the driving sleeve ( 11 ) and driven sleeve ( 12 ), respectively.

14. A hand-held machine tool according to claim 9 , further comprising a transmission gear unit ( 16 ), said transmission gear unit ( 16 ) being driven by said driving motor ( 15 ) to rotate said impact mechanism ( 5 ), wherein a second safety clutch ( 17 ) is arranged in the flow of force between the driver motor ( 15 ) and the transmission gear unit ( 16 ).

15. An at least partially rotating and axially percussive hand-held machine tool having a tool receptacle for receiving a tool, comprising:

an impact mechanism ( 5 ) having a guide tube ( 6 ) in which a percussion piston ( 7 ) is driven in an axially percussive manner by a pneumatic spring ( 8 );

a driving motor ( 15 );

a slip clutch ( 10 ), encloses the guide tube ( 6 ), is provided axially with cams ( 9 ) having torque-transmitting flank surfaces ( 20 ), and has a driving sleeve ( 11 ) and a driven sleeve ( 12 ) which are biased axially towards one another under pressure by a spring ( 13 ): and

a control sleeve ( 14 ) which is driven in rotation by the driving motor ( 15 ) for driving the driving sleeve ( 11 ) to, thereby, drive in rotation the slip clutch ( 10 ), wherein the control sleeve ( 14 ) and the driven sleeve ( 12 ) are rotationally decoupled;

wherein the driving sleeve ( 11 ) is positively guided in such a way that the driving sleeve ( 11 ), which is axially biased under pressure by the spring ( 13 ), is displaced axially away from the driven sleeve ( 12 ) and rotated relative to the control sleeve ( 14 ) when a limiting torque is exceeded and then is displaced axially towards the driven sleeve ( 12 ) under action of the spring ( 13 ), whereby the driving sleeve ( 11 ) strikes the driven sleeve ( 12 ) with the torque-transmitting flank surfaces ( 20 ) so that a rotational energy of the driving sleeve ( 11 ) is transformed into a brief tangential percussion which is transmitted to the tool by the tool receptacle.

16. A hand-held machine tool according to claim 15 , wherein the first control contour ( 19 a ) is formed as a broad pocket with at least one side extending axially at an inclination, and the second control contour ( 19 b ) is formed as an elongated groove which extends at least partially at an opposite inclination axially.

17. A hand-held machine tool according to claim 16 , wherein the first control contour ( 19 a ) is formed as a triangular pocket whose apex is situated axially on the spring side and whose two sides extend, respectively, at an inclination axially, and the second control contour ( 19 b ) is formed as an elongated groove which extends axially at an opposite inclination so as to be angled in a V-shaped manner.

18. A hand-held machine tool according to claim 15 , wherein the control sleeve ( 14 ) is arranged coaxially inside the driving sleeve ( 11 ).

19. A hand-held machine tool according to claim 15 , wherein at least two cams ( 9 ) are distributed circumferentially in a symmetric manner for the driving sleeve ( 11 ) and driven sleeve ( 12 ), respectively.

20. A hand-held machine tool according to claim 15 , further comprising a transmission gear unit ( 16 ), said transmission gear unit ( 16 ) being driven by said driving motor ( 15 ) to rotate said impact mechanism ( 5 ), wherein a second safety clutch ( 17 ) is arranged in the flow of force between the driver motor ( 15 ) and the transmission gear unit ( 16 ).