Method for making a moineau stator and resulting stator
AssigneePCM Pompes
InventorsLionel Lemay, Jean-Pierre Chopard
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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 internally 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.
Claims12
A method for manufacturing a stator of a Moineau-type gear pump, this stator comprising a stator cavity running axially overall inside an elongate body, the method consisting in manufacturing said stator cavity from a rigid-walled metal tube that is cylindrical of revolution, the method comprising the following steps:
- a preliminary mechanical-forming step during which said metal tube that is cylindrical of revolution is deformed so as to preform a rough form that internally approximates to the shape and dimensions of the desired stator cavity,
- then a definitive-forming step during which said rough form is subjected to a hydroforming process, performed inside a hydroforming chamber, on a molding form to obtain a tubular metal element forming a stator cavity with its shape and its exact interior dimensions such that once the stator has been assembled with a rotor, a positive clearance with the rotor is defined,
- and finally a step of mounting the tubular metal element that forms the stator cavity inside an outer casing forming a housing, with at least the ends of the tubular metal element being joined to said casing.
Dependencies are inferred from the claim text.