| 摘要 |
<p>A method of forming a probe (1) for capacitively measuring the distance to an object, for example to a turbine blade tip, together with a composite cable (2), comprises the steps of: (a) providing the interior of a metal tube (6) with a longitudinally extending conductor (4) and a mineral insulant (10) so that the interior is substantially filled with the conductor and insulant; (b) locating the metal tube (6) within the bore of a larger tube (8) after the exterior surface of the metal tube (6) and/or the interior surface of the larger tube (8) has been provided with a deposited layer of insulating material (12); (c) drawing the assembly of tubes so formed through a reducing die (with the exception of one end thereof) to form a cable part (2) of smaller diameter than the said one end; and (d) providing an electrode (14) at the said one end of the assembly to form the probe, which electrode extends over substantially the entire surface of exposed mineral insulant and is in electrical contact with the conductor. The method has the advantage that it enables a device to be manufactured at significantly reduced cost.</p> |
