Abstract: Pumping system comprising: a progressive cavity pump comprising a helical rotor inside a helical cavity of an outer stator; motor for driving the rotor, with a motor shaft coaxial to the axis of the stator cavity; and an intermediate shaft coupled, at its ends, by respective couplings, to the rotor shaft and to the motor shaft. Two devices consisting of two of these connected parts are constructed as a male device terminated by an axial stub and a female device terminated by an axial housing receiving the stub, at least two radial screws, not aligned, one of which is a cone-point set screw, connected the stub to the female device.

Abstract: This progressing cavity pump includes a helical rotor (2) mounted to turn inside a helical stator (3). The stator (3) and the rotor (2) are disposed such that the cavities (4) formed therebetween move from the inlet (5) towards the outlet (6). In this cavity pump, hydraulic regulation (HR) means are provided for obtaining internal recirculation of the pumped fluid between at least two of the cavities (4) under conditions capable of performing at least one function selected from: achieving the desired pressure distribution along the pump, stabilizing the temperatures, controlling the leakage flow rates, and compensating for the volumes of compressed gas.

Abstract: A pumping device is provided which comprises a Moineau pump with a helical rotor inside a helical cavity of a stator, driver means, and a drive connecting rod coupled by a respective coupling to a driving shaft of the driver and to one end of the rotor. Each coupling comprises a spherical head secured to the connecting rod and housed in a cavity that is cylindrical of revolution with the same diameter as and secured coaxially to the end of the rotor of the driving shaft; and a ball housed partly in a cup of the spherical head with its axis perpendicular to the axis of the connecting rod and partly in a lateral recess of the cavity.

Abstract: The invention concerns a Moineau type gear pump stator (1), comprising a stator cavity with global axial extension inside an elongated body, characterised in that the stator cavity is defined by a rigid-walled metal tubular element (3) having internall the shape and dimensions of the stator cavity such that, when it is assembled with a rotor, a positive clearance with the rotor is obtained.

Abstract: Gear pump, or Moineau pump, comprising two helical gears one inside the other, the internal helical gear, which is rotary (the rotor) having one tooth fewer than the external helical gear, which is stationary (the stator), characterized in that the rotor and the stator are made of respective materials which have respective coefficients of thermal expansion which lead to respective expansions of the rotor and of the stator which are such that an approximately constant clearance is maintained between the rotor and the stator over a range of ambient temperatures spanning between about 15.degree. C. and about 300.degree. C.

Abstract: Diasphragm pump having a delivery rate which can be continuously adjusted between a zero value and a maximum value, comprising:a continuously rotating eccentric drive member (6);a connecting rod (5) with a connecting-rod big end (11-14) fitted with a bearing (10) receiving, so as to rotate freely, the member (6) and the other end of which is coupled to a central area of the diaphragm (2);releasable coupling means in order to couple, in a selective manner, the connecting-rod big end to the member (6) during a desired fraction of stroke, which can be continuously adjusted by adjustment means (16-19).