Abstract In an analog display device, a pointer (1) can be reset by a stepping motor (2) which receives a constant number of pulses upon a reset command. In this way, starting from any position, the pointer is certain to reach the stop which corresponds to its zero position. In order in this connection to keep the mechanical force on the stop (6) and the transmission elements (3 and 4) between the pointer and the stepping motor small, the pulses for the resetting are produced initially with a relatively low pulse frequency and then with a higher pulse frequency. As a result, the stepping motor starts up reliably with a relatively high driving torque but gives off only a smaller driving torque when the stop in the zero position is reached.
In an analog display device for a motor vehicle, particularly a tachometer, having a pointer which is displaceable by a reversely driven stepping motor and resettable against a stop by the stepping motor, the improvement comprising: a pulse generator which is controlled by a reset command and upon each reset command and upon each reset command emits a constant number of pulses to the stepping motor a voltage detector means for controlling said pulse generator, and wherein the controlled pulse generator includes means for emitting said constant number of pulses initially with a pulse frequency which is below a start-stop frequency of the stepping motor and thereafter with a pulse frequency which is above said start-stop frequency.
Claim 2
Dependent Claim
117 words
In an analog display device for a motor vehicle, particularly a tachometer, having a pointer which is displaceable by a reversely driven stepping motor and resettable against a stop by the stepping motor, the improvement comprising: a pulse generator which is controlled by a reset command and upon each reset command and upon each reset command emits a constant number of pulses to the stepping motor a voltage detector means for controlling said pulse generator, and wherein the controlled pulse generator includes means for emitting said constant number of pulses initially with a pulse frequency which is below a start-stop frequency of the stepping motor and thereafter with a pulse frequency which is above said start-stop frequency.