Apparatus for transporting machine tools and work tools

Abstract

An apparatus for transporting a machine tool such as a robot arm comprises: upper and lower track rails each having a square or circular cross-sectional shape which are horizontally arranged in parallel so as to be away from each other in the vertical direction; and a casing slidably inserted therebetween. Rack tooth trains are formed on the lower surface of the upper track rail and on the upper surface of the lower track rail. The casing has an almost H-shaped cross-sectional shape and comprises a casing main body and two side plates attached at both end surfaces thereof. Rail side track grooves and casing side track grooves are formed on the inner wall surfaces of the track rails and casing main body. Balls are inserted between the corresponding opposite track grooves. A return passage is formed in the casing main body, ball direction turning passages are formed in the side plates, and the return passage is coupled with the casing side track grooves, thereby forming an infinite circulating passage for the balls. A pinion is rotatably arranged at the central position in the longitudinal and transversal directions of the casing main body. When the lower track rail is fixed to the fixed table and the casing main body is moved, the upper track rail moves in the same direction as the casing at the double speed.