Disclosed herein is an industrial robot equipped with an articulated arm unit which includes a first arm, second arm, a holder case and a holder. The basal end portion is pivotally attached to a shoulder shaft, which is formed of a first and second shafts disposed on the same axis and rotatable independently from each other. A differential transmission mechanism is arranged over mutually-opposing end portions of the first and second shafts. First drive means is formed by the first shaft and first coupling means so as to rotate the holder. Second drive means is also formed by the second shaft and second coupling means so as to rotate the holder case. The second drive means is also provided with third coupling means, which is also connected to the differential transmission mechanism, so as to compensatively rotate the holder. Owing to the adoption of the above structure, the above industrial robot can actuate its holder or arms independently without developing any induced motion at other parts of the industrial robot. Since a compensatory mechanism is provided at a basal part of the arm unit for the holder, the free end portion to which a hand is attached can be constructed in a small size. It is easy to teach handling work to the above industrial robot.

An automatic press line is disclosed which has a series of presses with a conveyor for transporting a succession of workpieces from one press to the next, and loading/unloading devices mounted one to each end of each press for loading and unloading the workpieces into and from the press line and for the transfer of the workpieces from press to press via the conveyor. Each loading/unloading device has a carriage to be controllably moved up and down on a support frame. The carriage carries a parallelogram linkage comprising a top link mounted to the carriage for up and down motion relative to the same, a pair of side links extending in a vertical plane, and a bottom link to which there is affixed a work carrier having suction cups. Extending between the carriage and one of the side links, a drive lever is swung back and forth to cause the parallelogram linkage to reciprocate the work carrier in a horizontal direction. The horizontal motion of the bottom link of the parallelogram linkage combines with the up and down motion of the carriage to enable the work carrier to move the successive workpieces into or out of the press. The support frame may be moved transversely of the press line for a change of press dies.

A robot having an arm and an adapted actuating mechanism of a parallelogram construction, formed of vertical arms having the forward and rearward movement regulated within a fixed range, parallel rods having the up and down movement regulated within a fixed range, upper links and a forward horizontally extending horizontal arm is supported by side plates. At least the above mentioned vertical arms are provided with an X-axis driving device and the parallel rods are provided with a Z-axis driving device and means to balance the load of the work and arm mechanism.

A mechanism for handling and manipulating a load including a horizontal work beam formed of a parallelogram linkage with a pair of arms interconnected by links. The work beam is pivotally mounted on a retaining part which is adjustably vertically mounted on a rotatable pillar. A counterweight is provided on the work beam for counterweighting its weight. A roller is movable horizontally in a trackway and connected to the work beam with the trackway elevated by a piston and cylinder along the pillar.

A linkage mounted counterweight for offsetting a load at the free end of an articulated boom crane (20). The articulated boom crane (20) includes an articulated boom (23) that includes an elevate linkage (25) and a telescoping section (24) is disclosed. The elevate linkage (25) includes a lower section (42) and a mid section (44). The counterweight (60) is located on the lower section (42) near where the lower section (42) is hingedly attached to the base of the crane (20). As the articulated boom (23) is raised from a stowed position, the counterweight moves away from the tilting fulcrum (F) of the articulated boom crane (20) to assist in maintaining the stability of the crane.