Multipurpose iydraulic shock absorber for vehicle

The invention concerns a shock absorber wherein all the adjustable means ( 70, 71 ) determining compression phase damping are arranged in the head ( 61 ) of the reservoir (R) and are externally accessible without disassembling, and those ( 71 ) adjusting low-speed compression, comprise a tubular body ( 75 ) for preload adjustment by being screwed in the head ( 61 ) of the reservoir, and overlapping outside thereof through an external manoeuvring head (75a), and, inside the reservoir, through an active end configured as a seat ( 82 ), said tubular body ( 75 ): a) communicating with the shock absorber wide cross-section chamber (G), b) being axially traversed by the adjusting screw ( 70 ) bearing, at its end inside the reservoir (R), the valve ( 72 ) with its spring-type setting means, and c) including, in its part configured as a seat ( 82 ) for the valve ( 72 ), at least a radial groove ( 81 ) forming an outlet channel determining the preload, the passage cross-section of said channel being determined by the distance between the terminal side ( 82 ) of the tubular body ( 75 ) and the inner side ( 61 a) of the head ( 61 ).