| 摘要 |
<p>A measuring system for a numerical control machine tool comprising a detecting head (3), for contacting a workpiece (1) to be checked and for transmitting an optical coded signal (8) to a remote transceiver unit (11) that, in turn, can transmit an optical switch on signal (10) to the head (3). The transceiver unit (11) is connected, by means of a cable (45) including separate lines (43, 44) for the transmitted and received signals, to an interface unit (12), in turn connected to a computerized numerical control unit (13). In the event that faults occur in the transmission between the head (3) and the interface unit (12), a test takes place so as to identify in which part of the system the fault is located. A test signal is generated by suitable means (38) in the interface unit (12), transmitted from the transceiver unit (11) towards a reflecting surface (16), reflected by the latter, received by the transceiver unit (11) and sent to the interface unit (12). If the test outcome is positive, it means that head (3) is the cause for the malfunction. In the contrary, the test continues, by shortcircuiting the connection lines (43, 44) first to one, then to the other end of cable (45) for excluding from the test the transceiver unit (11), and cable (45) itself.</p> |
