PURPOSE: To temper shocks due to inertia caused from stop, etc. by means of using a shock damper incorporated with a piston which provides an orifice in an air-tight cylinder, in a working hanger which hangs and conveys works of automobile body, etc.

CONSTITUTION: A shock damper 34 is incorporated with a piston 36 in which an orifice 38 is penetrated through, and springs 39, 40 to compensate buffer force are installed on both sides of the piston 36. When a traveling working carrier arrives at its stop position, an arm tip part 14' of a front carrier 7 is brought into contact with a stopper 16 which is provided on a free rail 4, and driving force is released by disengaging from a pulling dock 3. In this case, though shock due to inertia from a hanger frame 21 occurs, a front connector 27 has a momentary tilt, then the piston 36 is moved in the shock damper 34 in order to absorb shocks.