Abstract: A direct-teaching playback type polishing robot comprising a first arm and a second arm, a polishing tool suspended from a free end of said second arm, horizontal high-lead ball screws having nuts connected to said arms, respectively, and a servo-motor and an encoder mounted at a free end of threaded shaft of each of said ball screws in such a manner that rotation of said servo-motor advancing the corresponding nut to swing the corresponding arm independently of the other arm.

Abstract: A starter for internal combustion engines comprising a driving shaft to be driven by the air motor, a main valve for controlling the flow of compressed air to the air motor, and an air piston to advance the driving shaft to a position for starting the engine. Before feeding compressed air through the main valve to the air motor, a branched stream of compressed air is fed through a sub-valve to the air motor to rotate it at low speed and also to the main valve and the air piston to actuate them.

Abstract: A Scotch yoke mechanism for actuating opposed-piston gas compressor is disclosed. The mechanism comprises a crank pin eccentrically extending from an end of a main drive shaft, a slider rotatably surrounding the crank pin, and a yoke defining a pair of opposed parallel sliding surfaces for confining the motion of the slider only to the sliding motion along the surfaces, said yoke further defining a pair of outwardly extending connecting rods for connecting oppositely disposed pistons on either side of the york, whereby the orbital motion about the axis of the main drive shaft causes the slider to reciprocate the yoke and thus oppositely disposed pistons.

Abstract: In an oil-free multistage gas compressor comprising cylinders, a plurality of compression pistons in respective cylinders and a transmission mechanism for reciprocating said compression pistons through guide pistons serially connected to said compression pistons, the improvement wherein a common space where these pistons come in and out is defined adjacent the connections, and a diaphragm is disposed in said space transversely whereby said compression pistons are oil-tightly separated from said guide pistons.