| 摘要 |
PURPOSE:To perform accurate and stable operation by embedding a thermal switch (THSW) in a linear motor (LIM) device. CONSTITUTION:The THSW 12 which detects temperature variation is embedded in the LIM mounted on a moving carriage 1 and connected to a receiving head 10 provided to the carriage 1. Then, the magnetic resonance between the head 10 and a detection head 16 is caused by the coupling between their provided coils by magnetic flux and a resonance circuit as a detector on a ground side for the head 10 consists of the head 16 and terminals T1 and T2. In a normal state, the THSW 12 is on and the quality (Q) of the resonance circuit decreases owing to the loss of the head 10. Then the THSW 12 is normally closed and open in case of temperature abnormality and when the THSW 12 is open owing to the temperature abnormality, its resistance is zero and the Q of the resonance circuit increases. This variation in the Q is amplified by a detecting circuit 11 and compared by a comparator with a specific value to detect the tempera ture variation of the LIM accurately, thereby precluding burning.
|
