Striking hand-held tool
AssigneeHilti Aktiengesellschaft
InventorsMarkus HARTMANN, Rory BRITZ
Life of this patent
Estimating the term…
Abstract
A hand-held tool has a tool holder for holding a striking tool on a working axis, an electric motor, and a striking mechanism. The striking mechanism has an exciter piston moved by the motor, a striker coupled to the exciter piston by a pneumatic chamber arranged between the exciter piston and the striker, and a ram arranged in the striking direction of the striker piston. In a working position the ram rests counter to the striking direction against a stop. A stationary shut-off valve has a valve seat and an elastic shut-off member, wherein the elastic shut-off member in a relaxed state has a basic form which lifts from the valve seat, and wherein in the working position the elastic shut-off member is forced by the ram into a tensioned form resting against the valve seat.
Claims21
(canceled)
The hand-held power tool according to claim 8, wherein the shut-off body and/or the valve seat cannot move along the working axis relative to the percussion mechanism.
The hand-held power tool according to claim 8, wherein the shut-off body comprises a resilient ring, and the valve seat is arranged at a radial spacing from the resilient ring, the shut-off body being arranged along the working axis such that the rivet header moves into the shut-off body in the working position, and the shut-off body is resiliently spread apart by the rivet header until the shut-off body is resting against the valve seat.
The hand-held power tool according to claim 8, wherein the shut-off valve comprises a resilient ring having a circumference, the resilient ring being divided into the valve seat and the shut-off body by a notch running around the circumference of the ring, and a cut that extends along the working axis being provided in the shut-off body.
The hand-held power tool according to claim 8, wherein the pneumatic chamber comprises a throttle opening for exchanging air between the pneumatic chamber and an area around the hand-held power tool.
A hand-held percussion power tool, comprising
- a tool holder for holding a percussion tool on a working axis;
- an electric motor;
- a percussion mechanism, which comprises an exciter piston that is moved in a percussion direction by the electric motor;
- a percussion piston, which is coupled to the exciter piston by a pneumatic chamber arranged between the exciter piston and the percussion piston;
- the pneumatic chamber having a radial opening, and a rivet header that is arranged in front of the percussion piston in the percussion direction, the rivet header resting against a stop counter to the percussion direction when in a working position;
- a stationary shut-off valve, which comprises a valve seat and a resilient shut-off body, the resilient shut-off body having, in a relaxed state, a basic form that differs from a form of the valve seat, and in the working position the resilient shut-off body being forced by the rivet header into a tensioned form in which it fully rests against the valve seat;
- and
- a check valve, having an input side and an output side, wherein the check valve is connected to the stationary shut-off valve on the input side and to the radial opening on the output side.
Dependencies are inferred from the claim text.