| 摘要 |
A chain saw includes a motor unit and a guide bar clamped thereto by a clamping plate. The guide bar, which supports a saw chain, has a longitudinal slot formed therein. Clamping bolts carried by the motor unit pass through the slot and through the clamping plate for securing the clamping plate to the motor unit. One (or both) of the side edges of the slot includes corrugations. The clamping plate includes a hole aligned with the corrugations to enable a toothed key to be arranged in meshing engagement with the corrugations whereby a rack-and-pinion relationship is formed. By manually rotating the key, the guide bar is longitudinally displaced for varying the tension on the saw chain. |
