Abstract: An overload clutch is described, having two clutch bodies (11, 12), one of which is mounted rotationally fixed and the other of which is mounted so it is rotatable on a clutch carrier (3), and which may be coupled in the axial direction, of which the axially displaceably mounted clutch body (12) is impinged to disengage, and having a holding unit adjustable as a function of the size of the transmitted torque for the clutch engagement. In order to provide advantageous triggering conditions, it is suggested that the holding unit comprise a switching unit (16), which releases the axial actuator travel of the displaceably mounted clutch body (12) and may be actuated by an actuating drive connected to an energy accumulator (23).

Abstract: A process brings out a high contrast in natural grain of a naturally pale wood via infrared irradiation having a wavelength which is as long as possible. This infrared radiation can come from a conventional infrared emitter or, more preferably, from a carbon dioxide laser. Due to the contact-free heating near the surface which is effective in a stagnant ambient atmosphere, the new wood part of the grain is browned, while the harder old wood part remains essentially unbrowned. This causes the natural grain of the wood to stand out in contrast. Due to the contact-free and turbulence-free mode of operation of the heating, the grain pattern produced is uniform. Any scratches or chatter marks in the wood are simply covered over and remain invisible.