Power tool chuck

1. A chuck comprising:

a chuck body that supports a plurality of jaws that are moveable radially but not axially relative to the body;

an outer sleeve that is axially fixed with respect to the chuck body; and

a nut coupled to the outer sleeve, the nut being movable axially and rotationally relative to the chuck body;

wherein the nut interacts with the jaws such that when the outer sleeve rotates, the nut moves axially and rotationally relative to the body and the jaws move radially but not axially relative to the body.

2. The chuck of claim 1 , wherein when the nut moves axially and rotationally relative to the chuck body, the jaws move towards or away from one another.

3. The chuck of claim 2 , wherein the chuck has a front end at which the jaws are configured to hold a bit; and

wherein the jaws move away from one another when the nut moves axially toward the front end.

4. The chuck of claim 3 , wherein the chuck has a rear end opposite the front end; and

wherein the jaws move towards one another when the nut moves axially toward the rear end.

5. The chuck of claim 1 , wherein the nut includes internal threads.

6. The chuck of claim 5 , wherein the jaws include external threads that mesh with the internal threads on the nut.

7. The chuck of claim 1 , further comprising a lifter configured to push the jaws away from one another when the nut is rotated in a first direction.

8. A power tool comprising;

a housing;

a motor disposed in the housing; and

a chuck configured to hold an accessory, the chuck being selectively driven by the motor;

wherein the chuck comprises:

a chuck body;

a plurality of jaws disposed at least partially in the chuck body and moveable radially but not axially relative to the body;

an outer sleeve that is axially fixed with respect to the chuck body, and selectively rotatable with respect to the chuck body; and

a nut coupled to the outer sleeve, the nut being movable axially and rotationally relative to the chuck body;

wherein when the outer sleeve rotates, the nut moves axially and rotationally relative to the body and the jaws move radially but not axially relative to the body.

9. The power tool of claim 8 , wherein when the nut moves axially and rotationally relative to the body, the jaws move towards or away from one another.

10. The power tool of claim 9 , wherein the chuck has a front end at which the jaws are configured to hold a bit; and

wherein the jaws move away from one another when the nut moves axially toward the front end.

11. The power tool of claim 10 , wherein the chuck has a rear end opposite the front end; and

wherein the jaws move towards one another when the nut moves axially toward the rear end.

12. The power tool of claim 8 , wherein the nut includes internal threads.

13. The power tool of claim 12 , wherein the jaws include external threads that mesh with the internal threads on the nut.

14. The power tool of claim 8 , wherein the chuck further comprises a lifter configured to push the jaws away from one another when the nut is rotated in a first direction.

15. A chuck comprising:

a chuck body having a front end and a rear end;

a plurality of jaws, the plurality of jaws configured to hold a bit;

an outer sleeve, the outer sleeve being axially fixed relative to the chuck body, the outer sleeve also being selectively rotatable with respect to the chuck body; and

a nut coupled to the outer sleeve, wherein the nut is located internally of the outer sleeve and is movable axially and rotationally relative to the chuck body;

wherein the nut includes a nut threaded portion on a surface of the nut;

wherein the jaws include a jaws threaded portion on a portion of the jaws;

wherein the nut threaded portion are engaged with the jaws threaded portion; and

wherein when the outer sleeve rotates in a first direction, the nut moves axially toward the rear end and rotationally relative to the body and the jaws move toward one another.

16. The chuck of claim 15 , wherein when the outer sleeve rotates in a second direction opposite the first direction, the jaws move away from one another and the nut moves axially toward the front end.

17. The chuck of claim 16 , further comprising a lifter which pushes the jaws away from one another.

18. The chuck of claim 15 , wherein the jaws are axially fixed relative to the chuck body.

19. The chuck of claim 15 , wherein the jaws are axially fixed relative to the outer sleeve.

20. The chuck of claim 15 , wherein the nut has a frustoconical shape.