Abstract: A swash plate assembly converts rotary motion to reciprocatory motion to reciprocate a diaphragm in a high frequency medical ventilator; the motor which drives the assembly is pivotally mounted for variation of the stroke of reciprocation thereby varying the tidal volume displaced by the diaphragm.

Abstract: The invention provides an installation for testing a well by pumping by means of a submerged pump and a process for use thereof. The assembly 6 formed of an hydraulic pump and motor is carried by one end of a reinforced flexible tube 1 wound through a pulley 7 on a drum 3 actuated by the surface motor 8. . In the sheath of tube 1 are housed electric conductors 2 for supplying the motor of assembly 6. Sensors detecting the level of fluid in the well allow the submergence depth of the pump to be detected, the signals coming from this detection being able to be used to control motor 8 at the submergence depth ensuring a given flow rate. The invention applies to determination of the flow rate, pressure and temperature characteristics of a well.

Abstract: A drive mechanism suitable for vertical pumps driven by hollow shaft motors includes an output shaft, a variable speed transmission unit for mounting above the motor, and means for vertically adjusting the position of the output shaft, the adjusting means being located above the transmission unit.

Abstract: A rotary pump assembly including a pump having a pump housing, a pump shaft disposed within the pump housing, a runner mounted concentrically on the pump shaft, a motor having a motor housing, and an intermediate housing interconnected between the pump- and motor-housings. The pump shaft has an end facing the motor, and the pump shaft end is formed as a hollow shaft fittingly mounted on the motor shaft. A bearing support is disposed in the intermediate housing for supporting the hollow pump shaft end, and is formed as an axial bearing with substantially no radial bearing capacity.

Abstract: An adjustable coupling for operatively connecting the shaft of a low-pressure deep well pump to the shaft of a high-pressure booster pump whereby both pumps may be driven by a common prime mover.

Abstract: A hydraulic pump apparatus including an outer housing having internal walls which are spherically configured, a hydraulically actuable variable position control ring which cooperates with the spherical housing walls to define the geometry of a hydraulic working cavity, and a rotor assembly having vanes which divide the working cavity into a plurality of working chambers and which follow the position of the control ring to vary the volume of the working chambers so as to move fluid into and out of inlet and outlet ports, respectively. The vanes are supported by a plurality of concentric rings which are attached in gimbal fashion to a rotor hub and pin assembly.