The present invention relates to hand-held power tool, in particular a rotary hammer and/or a percussion hammer, with a housing and vibration-damped handle that is spring-supported against the housing.
With hand-held power tools with an impact drive in particular, such as rotary hammers, chisel hammer, and the like, the hand-held power tool may be subjected to considerable vibrations. When these vibrations are transferred to a handle that is used to press the hand-held power tool against a work piece, the operator perceives the vibrations to be uncomfortable, and long-term exposure thereto may even result in injury. For this reason, double-shelled housings, with which the entire hammer is suspended in an outer shell such that it is resilient in the working direction, have been used to provide linear vibration damping of rotary hammers. This design is relatively complex and expensive, however.
Publication WO 03/011532 makes known a machine tool of the type described initially, which includes a vibration-damped, C-shaped handle that supported via springs against the housing. This handle includes two essentially parallel legs, which are guided into complementary recesses in a grip end of the housing in the working direction of the machine tool such that they are linearly movable. To ensure that the two legs do not tilt in the recesses and then move in a synchronous manner with each other relative to the housing when the operator applies a compressive force to the handle on only one side or not parallel to the working direction of the machine tool, the two legs are connected with the housing via a lever, the outer ends of which are hingedly connected to the particular legs, while their inner ends are hingedly connected to a region of the machine housing located between the two legs of the handle. Since there is no direct connection between the handle and the housing of the machine tool, a good decoupling of the handle from the vibrating housing is attained. The lever design also increases the stability of the handle.
In addition, publication DE 10 2004 019 776 A1 has also already made known to hingedly connect the two legs of a handle of a machine tool with the housing of the machine tool, to dampen vibrations using coupling elements.
In addition, a machine tool with a vibration-damped handle is made known in DE 101 38 123 A1, with which one of the coupling elements that is hingedly connected with the handle and the housing is accommodated inside the hollow handle in a space-saving manner, and the other is accommodated inside the housing.
While these designs make it possible to attain satisfactory vibration damping and decoupling of vibrations, it is not always possible to integrate these designs in the housing and/or the handle, or to accommodate them inside the housing and/or the handle such that they take up a small enough space in the working direction of the machine tool that they do not result in an increase in the overall length of the machine tool.
USPTO Backgrounds
USPTO Backgrounds