Abstract: A compressed air pump comprising a compressed air piston motor (11) having a cylinder housing (12) and a low pressure piston (22) moveable between first and second end wall parts (13, 14) and a hydraulic piston pump (15) in the second end wall part (14). One side of the low pressure piston and the first end wall part together define a working chamber (21) and the other side of the piston (22) abuts and drives the hydraulic piston (24). A pilot piston (25), which is controlled by the low pressure piston (22) controls the supply of compressed air to the working chamber (21). A spring powers the return stroke of the low pressure piston and the hydraulic piston. The pilot piston (25) is housed in a pilot cylinder (35) incorporated in the first end wall part (13) and is mounted for movement between a first position and a second position. In the first position compressed air can be passed from an inlet (17) in the end wall part to the working chamber.

Abstract: An hydraulic tensioning tool for tensioning reinforcing cables, rods or like devices in concrete structure. A first working piston-cylinder device (21) is arranged to effect the actual work of tensioning the cable, while a second working piston-cylinder device (22) causes the cable to be anchored to a cable lock (12). The first device (21) includes a tensioning cylinder (23) and a tensioning piston (24) having mounted on the outer free end (25) thereof a readily removed cable holder (14). The tensioning cylinder (23) of the first piston-cylinder device and the locking cylinder (27) of the second piston-cylinder device (22) are accommodated in a common cylinder housing (11), although separated by a partition (29) which forms the bottoms of respective cylinders, such that the tensioning piston (24) and the locking piston (26) for the cable lock (12) are movable in mutually opposite directions during their respective working strokes.