The invention comprises a panel lifting apparatus having a U shaped horizontal frame with rollers mounted along the bottom for transporting the frame from place to place. A pair of inclined channels are mounted in spaced relation along the apex of the frame. A pair of hooks having rod like extensions are each mounted on a frame having rollers for rolling along the inclined channels to roll the hooks upward and downward along the inclined channels. A crank and drum are rotatably mounted on one of said channels. A cable has its ends attached to the pair of hooks and an intermediate portion extending through the drum whereby rotation of the drum by the crank in one direction causes the cables to wind in opposite directions on the same drum to wind the ends of the cables upward simultaneously and thereby draw the hooks upward on the channels simultaneously. The channels extend sufficiently downward to be adjacent the frame rollers and the ground that the hooks may be lowered by the crank to immediate adjacency to the ground and are adapted to receive a drywall panel thereon adjacent the ground. The hooks may lift the panel up to a height where they may be transferred onto a panel lifter having an extended height capability.

A synchronous actuator comprises a telescopic cylinder assembly having at least three pivotally connected cylinders, a drive assembly and a driven assembly. The drive assembly is connected to two adjacent cylinders. The driven assembly is connected to three adjacent cylinders. With the drive assembly and the driven assembly, the cylinders of the telescopic cylinder assembly can be extended or retracted synchronously in axial direction.

The invention comprises a panel lifting apparatus having at least three telescoping elongated sections telescoping into one another and all telescoping into a non-telescoping elongated frame member. Three separate chain length segaments not directly connected to one another act to raise and lower the telescoping sections. The first chain segament has its upper and lower end mounted to the upper and lower end of the first telescoping section. The second chain segament has its upper end connected to the upper end of the non-telescoping section and its lower end connected to the lower end of the second telescoping section. The third chain segament has its upper end connected to the upper end of the first telescoping section and its lower end connected to the lower end of the third telescoping section. The non-telescoping section has a gear drive with its output gear engaging the first chain segament to raise and lower the first chain segament to thereby raise and lower the first telescoping section. The raising and lowering of the first telescoping section raises and lowers simultaneously the second and third telescoping sections through the chain segament connections.

The invention concerns an improved device in pallet loaders, comprising an upright frame (1) and a pair of horizontal lifting fork members (2) which may be raised and lowered together with said frame (1) by means of a lifting mechanism. The lifting fork members (2) are equipped at their outermost end with one support wheel (4) each, which wheels are attached to an articulated arm (14) arranged to be pivoted downwards. The frame (1) and the lifting fork members (2) may be raised and lowered by means of a rack (6) which is connected via a cable, wire on chain (10) to an articulated, two-armed rocker arm (13). In turn, the latter is connected to the articulated arm (14) by means of a traction rod (15) which is associated with the arm (14). Upon upwards motion of the rack (6) and thus of the frame (1) a pulling force on the cable (10) will be transferred via the rocker arm (13) and the traction rod (15) to the articulated arm (14), which then swings downwards, thus raising the lifting fork members (2).

An actuating device intended for spacially moving a mobile part in relation to a fixed point, characterized in that it includes a motor (1) driving, around its shaft (2), a winding element (4) pulling a mobile lifting element (9) connected to a fixed point (22) used as anchoring point for the flexible element (4) and sliding, perpendicularly to the axis of the thus constituted pulley block mechanism, in a tube-shaped guide (15) inside which it is housed and compressing a return spring (10) ensuring the return in extension of the mobile element (9), in such a way that this device works in traction and without any buckling stresses.