Keyless chuck

Patent 5195760 Issued on March 23, 1993. Estimated Expiration Date:

June 12, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

914255

1159248

2406444

2553990

2683041

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Inventors

Assignee

Black & Decker Inc.

Application

No. 537038 filed on 06/12/1990

US Classes:

279/60, Obliquely guided reciprocating jaws279/902KEYLESS TYPE SOCKET

Examiners

Primary: Bishop, Steven C.

Attorney, Agent or Firm

Dearing; Dennis A., Del Ponti; John D., Yocum; Charles E.

Foreign Patent References

1929242 DE. 06/12/1971
2639214 DE. 03/12/1978
3114503 DE. 11/12/1982
3424679 DE. 02/12/1986
3541964 DE. 06/12/1987
3713547 DE. 09/12/1988
1023518 FR. 03/12/2012
191959 GB. 01/12/2012
1566855 GB. 05/12/1980

International Class

B23B 031/16

Abstract

A keyless chuck (10; 301) comprises a jaw housing (28; 303) with jaws (32; 333, 335, 337 ) which are slidably mounted in guideways (40; 319, 321, 323) between a rearward opened position and a forward closed position. A jaw thrust member (34; 345) is coupled to the jaws and is slidably mounted in the jaw housing to apply a thrust force to the jaws and to maintain the jaws in the same relative axial location. A nut (42; 355) is fixed to the jaw housing and has a threaded opening (46; 357) coaxial with the chuck axis (Ax). A threaded spindle (48; 305) is engaged in the nut opening and is movable forwardly to apply clamping force to the jaws and rearwardly to remove clamping force. The spindle preferably engages the jaw thrust member through a small area contact patch (72; 401) to limit operating friction. The jaws either may be opened and closed responsive to rearward and forward movement of the spindle respectively or to simplify loading of a bit in the chuck, may be spring biased forwardly to a closed position (self-centering) and thus not movable responsive to movement of the spindle. A lock mechanism (22, 104, 42; 309) is preferably provided to limit relative rotation between the nut and spindle to prevent the application of excessive clamping force and to limit removal of clamping force. The lock mechanism also preferably permits incremental self-tightening when in the locked position through an automatic tightener (397) and through the sizing and spacing of two sets of teeth (373, 375) to limit the application and removal of clamping force on a drill bit. To limit the run out in a finished chuck, deformable (during assembly) interfaces (204; 401) are preferably provided between the jaw housing and nut and between the spindle and jaw thrust member (stop). To further enhance the accuracy of assembly and to reduce run out, the spindle and nut preferably have a smoothed walled interface (415, 417) to accurately control coaxial alignment of the nut and spindle.