Abstract: The specification describes a three-point regulator, for example of the pneumatic type, in the case of which with a drop and a rise in the measurement value of the regulation quantity after overcoming an operating distance a respective switch is operated. One switch is moved or turned by a servo-member (motor) in one direction and the other switch is moved or turned by the servo-member in the other direction. A feedback is provided which acts on both switches in such a manner that the operating distance is increased and accordingly the switched-on switch is switched off.

Abstract: A pressure transducer formed as a three-dimensional body is rendered flexible in order to permit fine adjustment of a machine tool seat formed thereon by the formation of holes and slits in the transducer body which cause portions of the body to operate as spring-like webs. An expansion box is located within the transducer and a pressure transmitter separate therefrom is connected thereto to enable pressure from the transmitter to be applied to the expansion box to cause flexing of the transducer body and fine adjustment of the position of the tool seat. Because of the particular arrangement of the holes and slits in the transducer body, the tool seat is able to be moved parallel to itself during the adjustment process.