Adjustment device for an internal combustion engine

A method for controlling the position of an adjusting member of an internal combustion engine, comprising the steps of:

• (a) providing an adjustment device comprising:
• i. a housing;
• ii. a drive motor disposed in the housing;
• iii. a first adjusting member drive shaft;
• iv. a set of gears operationally connected to the first adjusting member drive shaft and operationally connected to the drive motor;
• v. a first control device having a logic circuit and a bridge end circuit;
• vi. a non-moving Hall switch disposed fixedly in the housing;
• and
• vii. two pin magnets of differing polarity disposed in a fixed, pre-determined position to the first adjusting member drive shaft, and functionally-connected to the non-moving Hall switch, and disposed so that the non-moving Hall switch detects a polarity change with movement of the magnets and produces at least one signal, wherein the Hall switch is operationally connected to send the at least one signal to the control device, wherein the at least one signal serves to preset the running direction of the drive motor;
• and
• (b) feeding a positioning signal from an external control device to the first control device;
• and
• (c) comparing the positioning signal from the external control device with the signal of the Hall switch;
• wherein,
• (i) when the result of the comparison of the positioning signal with the Hall switch signal is that no definite signal is sent from the Hall device and neither of the pin magnets impinges on the Hall switch, then the signal from the control device is sent through to the motor and the motor continues to run, and
• (ii) when the result of the comparison of the positioning signal with the Hall switch signal is that a definite signal is sent from the Hall switch and one of the pin magnets is close enough to the Hall switch to switch the Hall switch, then the motor is stopped.