Device for locking and unlocking tubular members telescopically and concentrically slidable into one another

摘要

1. Device for locking and unlocking telescopic tubular elements which can be slid concentrically into each other, with a spindle drive with which the elements can be displaced against one another in succession, and with a locking device which on the displaced of one element, protects the following element against premature displacement with it and which causes an automatic coupling of each displaced element with the following element, and wherein the locking mechanism comprises at least one spring-loaded multiple-arm catch, which is hinged in the end region of each element, wherein at least one arm of the catch is formed as a locking arm and at least one arm is formed as an unlocking arm, to which arms there are assigned in the upper area of each outer and in the lower area of each inner element actuating and/or locking projections arranged thereon, which arms are formed in such a way that during an extension and retraction movement, the catch is released and engaged and/or locked by the actuated element, characterised in that the catch (28) is formed as a single, four-arm angle lever which can be swivelled on a pin (34) arranged on a mounting (32) secured in the upper area of the elements (8, 12), in which two arms (36, 38) are used as locking and two arms (40, 42) as unlocking arms, and in that on the elements (6, 8, 10, 12, 14) engagement mountings (44) and fixtures (48) are provided with openings (46, 60) and actuating projections (50, 58) which co-operate with the four arms (36, 38, 40, 42).