Abstract: An elongated portable structure for the use as a tent or the like, having an end panel at each end. Each end panel comprises an annular hoop of flexible, resilient, strip material which can be reduced to a much smaller dimension by twisting. A sheet of substantially non-stretchable, flexible fabric in the space within each hoop is secured to the hoop so that the sheet is maintained taut and will resist collapse or distortion of the hoop. The end panels are maintained in generally upright position by at least one spreader rod extending between the end panels, and struts connected to the ends of the rod and attached to the respective end panels. A rigid force distributor may be attached to each strut to engage the sheet within each hoop. A flexible fabric cover with an opening extends between the end panels to provide shelter for a person or persons occupying the structure.

Abstract: A gear pump or motor comprises a pair of rotary gears which are in external meshing engagement with each other. A thrust plate is pressed against the side faces of the gears by means of a plurality of pressure areas which are produced by means of a sealing and compensating unit. The unit is urged piston-like by virtue of fluid pressure chambers against the back of the thrust plate to engage it against the gears. Depending on the direction of rotation of the gears of the machine the pressure areas define the general configuration of a 3 or a .epsilon..