Method and device for producing a cavity in a stator of a progressive cavity pump

Abstract

In a method for producing a cavity (14) in a stator of an eccentric screw pump, material is removed in the interior of a stator blank (10) by means of a tool (11). In order that very long stators can be produced in one production operation, the tool (11) performs a rotational motion through a first shaft (12) and an eccentric motion around a second shaft (13), during which the stator blank (10) and the tool (11) are moved toward each other. A device for performing the method comprises (a) a bearing shaft (3) that can be coupled with its drive end to a first drive and that is rotatable around its longitudinal axis by means of the first drive; (b) a drive shaft (4) that can be coupled with its drive end to a second drive and is arranged in a borehole of the bearing shaft (3) and is rotatable around its longitudinal axis by means of the second drive form-fitting and relative to the bearing shaft (3), and (c) a machining tool (5), which is rotationally fixed connected to the machining end of the drive shaft (4) that can be inserted into the cavity and can be driven rotatably via the drive shaft (4) around the longitudinal axis of the drive shaft (4). The longitudinal axis of the drive shaft (4) intersects the longitudinal axis of the bearing shaft (3) at a point or is arranged askew to the longitudinal axis of the bearing shaft (3).

Dependencies are inferred from the claim text.