| 摘要 |
A chuck is mounted on a drive shaft and torque can be transferred to an inner ring (30) of the chuck from the drive shaft. A casing (28) of the chuck surrounds the inner ring and supports four circumferentially-spaced cam elements (40) for gripping and supporting the core. Each cam element comprises a cam pivotably mounted on the housing and operated by a cam roller (58) mounted on the inner ring. Relative rotation of the inner ring and the casing causes the cam roller to move along a cam surface on the underside of its cam and to raise either end of the cam to engage the core. A switching element (80) is housed in a chamber in the casing between each pair of cam elements. Each switching element comprises a detent spring (90) having a central detent and being captive within the chamber (82), and a detent roller (88) mounted on the inner ring. |
