GB1290395A - - Google Patents

Abstract

1290395 Testing abrasion resistance ROLLS-ROYCE Ltd 23 Dec 1969 62550/69 Heading G1S An apparatus for testing materials e.g. the insulation on electric cable, for resistance to abrasion comprises clamping means to hold the material, an abrading tool and means for causing relative reciprocating movement between the tool and the material. In Fig. 2 the tool 38 is mounted in a tool holder 30 which is attached to holder 26 arranged in bushes 24 to move vertically, the force exerted by the tool being varied by varying the position of counterweight 52. The material is clamped to platform mounted on bars 80 forming part of a carriage reciprocated by electric motor 104 via a shaft 106 eccentrically engaging a bearing in the base of the carriage. An electrically heated thermostated oven 60 surrounds the test material, the carriage moving relative thereto by means of the bars 80 passing through bushes 74 in the oven walls. In Fig. 5, the tool 244 is carried by a holder 238 sliding vertically in carriage 202 and biased downwardly by weight 240. The carriage is reciprocated by motor 204. The test material 256 is heated by a thermostatically controlled hot plate 210. The number of cycles of abrasion may be registered by a counter. An electric warning circuit having a visual and/or audible warning may be provided which is actuated when the abrasive tool cuts through the material to a conductor in the material e. g. in electric cable, or when the tool cuts through the full thickness of the material and contacts the metal table beneath. The warning circuit may also switch off the apparatus. The material to be tested may be arranged so that it sags during the test.