| 摘要 |
<p>A tool-les clamping device, particularly for clamping saw blades to the reciprocating drive shaft of a hand-held power saw, comprises two clamp members which secure the shank of the blade between them and which move relative to one another to clamp/unclamp the shank. This movement is caused by the linear (translational) or rotary movement of an independently moveable actuating member. In a first embodiment clamp member 12 is secured to the driveshaft and includes a recessed base 28 for receiving the blade shank. Clamp plate 13 locates within member 12, its movement being controlled by slots 19 (extending along the direction of the clamping force) and pins 20. Rotary sleeve 21 fits over member 12 and has slots 23 angled to the direction of the clamping force and receiving the ends of pins 20. Rotation of the sleeve (via actuating sleeve 14) causes a cam effect between the pins and the angled slots to move plate 13 towards or away from member 12. Sleeve 14 is frictionally retained at a given angular position on sleeve 21 by an acme thread. Spring loaded pin 29 positively locates within a corresponding hole in the blade shank if present. The above cam mechanism is employed in further embodiments of the invention. In a second embodiment clamping rods (13) are retained in transverse slots (67) in a rectilinear cover (65) and cammed by angled slots in a U-shaped clamping member (60) which slides within the cover and receives the blade shank. A third embodiment is similar to the second embodiment but employs two sets of cammed rods, with a clamping member mounted on each set of rods. In an alternative embodiment a cam comprising an actuator member (531) engaging with a ramp (49) on moveable clamp assembly (13, 49) moves said assembly relative to blade receiving clamp member 40.</p> |
