| 摘要 |
A percussion power tool assembly (10) comprises a hand-held percussion power tool (11), a chamber (12) mounted on the tool (11), and a fluid reservoir (14) supported independently of the tool (11). The percussion power tool (11) has a body (20) housing a reciprocating hammer (22) which impacts against tool bit (24) in a conventional manner. The hammer (22) is operated by compressed air admitted though valve (26) in feed line (28). The chamber (12) communicates with the fluid reservoir (14) though flexible hose (16). The chamber (12) surrounds the body (20) and has a flexible lining (30) defining a bladder which inflates/deflates in sympathy with fluid filling, or emptying from, the chamber. The deadweight of the hand-held part (18) of the assembly (that is, the tool and chamber combined) is varied by transferring fluid, e.g. water, in the reservoir (14) to the chamber (12), and reduced by returning transferred fluid to the reservoir (14). In practice, the deadweight of the tool is reduced to facilitate moving the tool, and is increased when the tool is in use to achieve required reaction force between tool and work piece with reduced contribution from the operator.
|
