| 摘要 |
PURPOSE:To increase the reliability of a measuring apparatus, by using two temperature detectors to give an alarm by utilizing that a difference between temperatures measured by the two temperature detectors increases when either of them turns faulty. CONSTITUTION:Two temperature detectors 20A and 20B are in contact with a specimen W for a prescribed time simultaneously, and measure the temperature thereof, and at the same time, a measuring head 15 engages with the specimen W and measures the dimensions thereof. When either of the two temperature detectors 20A and 20B turns faulty, a difference between the detected temperatures increases. A temperature difference computing means 3 computes each difference between the temperature measured by the two temperature detectors 20A and 20B: when this temperature difference turns larger than an allowable temperature difference stored in an allowable temperature difference storage means 5, a comparing means 4 delivers an alarm signal for informing the operator that either of the temperature detectors 20A and 20B is faulty. |
