Abstract: Hydraulic axial piston unit having a rotational group for driving or being driven by a driving shaft, and a tiltable displacement element for adjusting the displacement volume of the rotational group. The rotational group includes a rotatable cylinder block in which working pistons are mounted reciprocally moveable in cylinder bores for conveying hydraulic fluid from an inlet port to an outlet port on a valve segment. At least two control ports are located on the valve segment each between the inlet port and the outlet port. The control ports can be brought sequentially in fluid connection with the cylinder bores when the cylinder block is rotating. At least one hydraulic fluid injector is connected fluidly to one control port, for sequentially injecting pressurized hydraulic fluid via the control port into the passing cylinder bores. Via the other control port hydraulic fluid can be drained from passing cylinder bores.

Abstract: An above ground swimming pool having a rigid retaining wall using interconnecting components which are mainly slotted and notched to form the primary connection and minimally bolted to form the secondary connection.The retaining wall is supported by an improved "A" frame made up of three interfitted members held in assembled position by a tie bolt.The retaining wall has wall sections or sheets slid into opposite facing grooves of two "Z" bars mounted on the wall posts of the retaining wall.A sectional walk deck is snap-fitted to the retaining wall. A picket fence surrounds the walk deck and is connected to a flat plate passing through a slot in the rail post to sandwich the post between adjacent fence sections.