The invention relates to a hydraulic door actuator, in which a working piston (2) may be hydraulically driven against the force of a spring (5) and in which the spring force of the spring (5) may be adjusted.

This rotational movement tensions a restoring spring (35).

The inhaler has a tensioning device for the one-handed tensioning of a drive spring and release thereof.

A contact wire (6, 7, 10, 11) arranged inside the housing (2), is configured concentrically and is held under spring tension with an annular spring (10).

The invention relates to a hammer mechanism for a power tool, particularly for a hand power tool, especially for an electric hammer drill or an impact wrench, comprising a striker (2) that can be acted on by tensioning a spiral spring (3).

The mechanism assembly includes a cylindrical shaft that extends outward against the tension force of a spring from a housing component of the assembly.

Thus, the pressing force detected by a load cell (25) is fed back to a servo motor (9) to vary the tension of a spring (8) via the revolution of the motor.

The invention relates to a mouse trap (1) comprising a striking lid (10) which is linked to a base plate (2).

Said lid can be brought to a catching position by means of the tension of a striker spring (20).