Distance measurement
AssigneeBritish Steel Corporation
InventorsKerry Hill, Edward Butterworth
Life of this patent
Estimating the term…
Abstract
The invention is concerned with establishing the datum level of a lance or cartridge relative to the surface of a bath of molten metal in a metallurgical vessel. A voltage is applied to the movable lance or cartridge in such manner that contact of the lance or cartridge with the bath surface causes an earth leakage current to be established. Electrical circuitry is incorporated to open a circuit breaker upon flow of a predetermined earth leakage current and actuate an indication on a distance measuring device coupled to the movable lance or cartridge.
Claims11
Apparatus for determining the separation between first and second relatively movable objects comprising means connected to a first object for applying an electrical voltage to said first object, earth leakage current detection means electrically connected to said first object operable, upon establishment of an earth leakage current from said first object to earth through a second object connected to earth, when said first object contacts said second object, a circuit breaker triggered by said earth leakage current break an earth leakage circuit, and electrical means activated by said circuit breaker to initiate a reading on distance measuring means for recording the separation between the two objects.
A method of determining the separation between first and second relatively movable objects comprising applying electrical voltage to a first one of said objects, moving one of said objects towards the other to establish an earth leakage circuit, detecting the establishment of an earth leakage current from said first object to earth when said first object contacts said second object, and passing said earth leakage current through a circuit breaker to trigger said circuit breaker to break said earth leakage circuit and activate electrical means in said earth leakage circuit to initiate a reading on distance measuring means for recording the separation between the two objects.
Dependencies are inferred from the claim text.