PROTECTIVE DEVICE FOR TELESCOPIC SHAFTS Russian patent published in 1998 - IPC

FIELD: agricultural engineering, in particular, protective equipment for cardan shafts of agricultural tool drives. SUBSTANCE: protective device has outer and inner protective pipes 3,4 made from synthetic material and mounted in axial alignment one within another. Pipes 3,4 are positioned for movement in the direction of their longitudinal axis and may be closed. One pipe has groove extending in parallel with longitudinal axis of pipe and other pipe has at least one guiding radial rib extending in parallel with longitudinal axis and adapted for mutual engagement with groove. Inner surface of outer protective pipe 3 has at least two additional grooves faced to longitudinal axis. All the grooves are defined by pairs of ribs extending in parallel with longitudinal axis and protruding relative to inner surface of outer protective pipe 3. Pairs of ribs are disposed uniformly around longitudinal axis on inner surface of pipe 3. At least one connecting and guiding member is positioned on inner surface of outer pipe 3 and protruding toward longitudinal axis. Number of guiding ribs on outer surface of inner protective pipe 4 corresponds to the number of grooves in outer protective pipe 3. Ribs and guiding connecting members are configured to fit the form of outer protective pipe 3 and guiding ribs - to fit the form of inner protective pipe 4. Construction of device allows connection without rotation between inner and outer pipes 3 and 4 to be provided and friction to be reduced at radial loading. EFFECT: increased efficiency and enhanced reliability in operation. 4 cl, 3 dwg