Abstract: There is described a stairlift (1), comprising: a carriage (3) displaceable along a bent path, and a chair (5) carried by said carriage (3) and mounted on said carriage (3) for tilting about a horizontal axis of rotation (11); a horizontal-keeping mechanism (100) for keeping the chair (5) upright, comprising: an angle sensor (110) providing a signal (S(?)) indicative of the instantaneous value of an angle of rotation (?) between the chair (5) and the carriage (3); an orientation sensor (130) associated with the carriage (3) and providing a signal indicative of variations in the position (?) of the carriage (3); and an absolute-orientation sensor (140) associated with the chair (5), providing a signal (S(?) representative of the instantaneous value of the position (?) of the chair (5). The control members (101, 102) control said angle of rotation (?) on the basis of the signals (S(?), S(?) received.

Abstract: A control circuit (200) mounted on a printed-circuit board comprises a control element (100) having a plurality of inputs (110.sub.i). Operating switches (Si) are connected with respective inputs (110.sub.i) by print tracks (12.sub.i, 30.sub.i). A signal source (10) generates a plurality of mutually different signals (.phi..sub.i) which are passed to the various switches (Si) and whose characteristic is priorly known. In case of, for instance, a short-circuit, a signal of a switch may end up at an input of the control element that does not correspond with that switch, but the control element can recognize this error situation because the received signal then has a wrong characteristic. The control element can then ignore the operating instruction, and/or generate an alarm signal. Thus the risk of incorrect operation by short-circuiting between adjacent print tracks is reduced, and the print tracks can be arranged closer to each other on the printed-circuit board.