GB1421420A - Cable bushing - Google Patents

Abstract

1421420 Cable bushings RASMUSSEN GmbH 26 July 1973 [3 Aug 1972] 35550/73 Heading H2E A cable bushing with stress relief comprises a body 4 containing a cable passage 10 which extends through a bush part 5 mountable through an aperture 2 in a wall 1, e.g. of an electrical appliance, to which it is securable by a cap nut 9, and through a clamping part 6 in the wall of which is a tapped hole engaging a clamping screw 16 which can be driven to press the cable 21 against an opposite wall 18. The passage 10 comprises an entry part 11 through the bush part 5 and an adjoining exit part 12 through the clamping part 6, the axes x and y of the entry and exit parts being mutually inclined at an included angle of between 90 and 130 degrees. The walls of the entry and exit parts 11, 12 are conjoined on the inner side of the angle by a section 13 having a very small radius of curvature, or one or more edges. Preferably the angle between the axes x and y lies between 110 and 115 degrees, and the entry axis x is inclined to the axis of the bush part 5 by a small angle, which in the embodiment is 7À5 degrees. On the outside of the angle between the axes x and y the walls of the entry part 11 and exit part 12 are connected by a curved transition surface 14. The axis of the clamping screw 16 is perpendicular to the plane containing the axes x and y. The screw 16 may be fitted with a rotatable clamping taper 17, and the wall 18 may have a complementary depression 19. The exit part 12 may have a flared mouth 20 to avoid fretting the cable. The bush part 5 may have a radially protruding nose 8 engaging a radial groove 3 of the aperture 2 to prevent rotation. The cable 21 is installed by insertion into the entry part 11 whence it is guided to the exit part 12 by the transition surface 14. In use the cable is gripped between the clamping screw 16 and the wall 18, further stress relief being provided by the natural stiffness of the cable 21 which forces itself against the section 13, the mouth 20 and the bush part 5 or cap nut 9.