| 摘要 |
A hand tool comprising two moving parts; a rotating and a reciprocating part. The reciprocating part, carrying a machining tool, is imparted its movement from the rotating part via a crank mechanism with variable excentricity for adjusting the reciprocating part's length of stroke. A crank pin in said mechanism is therefore excentrically disposed on a rotatable, lockable slide excentrically journalled in a rotatable holder which is imparted its rotary movement from the drive means of the hand tool. Counterweights in the slide and its holder together counterbalance the movements of the reciprocating part corresponding to the varying lengths of stroke. Upon setting of the crank mechanism to the desired length of stroke, the counterweights are arranged to either work in conjunction or in opposition and are therefore rotatable relative each other to an extent corresponding to the relative movements of the slide and slide holder. |
