Rotor and/or stator designs and methods thereof to improve progressive cavity motor or pump durability. In one or more implementations, the rotor may have a variable outer diameter or variable stiffness along an axial length thereof. The stator may similarly have a variable inner diameter or variable stiffness, which may compliment or diverge from the variable outer diameter or variable stiffness of the rotor.

The invention pertains to an eccentric screw pump with a stator-rotor system, which includes a rotor with a rotor screw and a stator with an internal thread. The stator has a support element and an elastomer part, wherein the support element encloses the elastomer part sectionally over its entire circumference. The stator-rotor system has a mechanism for adjusting the stator, which is coupled to at least one sensor for determining actual operating parameters of the stator-rotor system by means of a control unit that activates the adjusting mechanism with consideration of the actual operating parameters determined with the aid of at least one sensor.

An operating method for a conveying device with an eccentric screw pump for conveying viscous construction materials comprising sensing a pressure of the construction material at an outlet of the eccentric screw pump when the eccentric screw pump is running and automatically switching off the eccentric screw pump if the pressure exceeds an upper limit value, otherwise continued operation of the eccentric screw pump. The method includes sensing a characteristic variable of the running eccentric screw pump and comparison of the characteristic variable with a first comparison variable, which is characteristic of operation with an open dispensing device and/or with a second comparison variable, which is characteristic of operation with a closed dispensing device, and switching off the eccentric screw pump if operation with a closed dispensing device is detected, otherwise continued operation of the eccentric screw pump.

The present invention relates to a Moineau pump-type quantitative liquid-discharging apparatus including a stator in which a slot hole is formed, a main shaft including a first shaft part and a second shaft part, which are eccentric with respect to each other, and a rotor which extends from the first shaft part and is inserted into the slot hole, first and second slide bearings to which the first shaft part and the second shaft part are rotatably coupled, respectively, and first and second sliders which guide the first and second slide bearings to move in directions to cross each other, wherein the movement directions of the first and second slide bearings are perpendicular to an extension direction of the rotor.

A system includes a pump, an inlet sensor, an outlet sensor, and a controller. The pump is configured for pumping fluid in a phacoemulsification system. The inlet sensor is coupled with an inlet port of the pump and is configured to sense an inlet temperature of the fluid at the inlet port. The outlet sensor is coupled with an outlet port of the pump and is configured to sense an outlet temperature of the fluid at the outlet port. The controller is configured to take a responsive action based a difference between the inlet temperature and the outlet temperature crossing a defined threshold.

An apparatus for removing rubber stator material from inside a housing includes a head, at least one blade, and an actuator. For example, the apparatus can be used to core out rubber material from the housing so new material can be molded therein. Also, the apparatus can be used to cut back excess rubber material newly molded in the housing. The head is rotated about an axis and is moved along the axis relative to the housing. The at least one blade is pivotably connected to the head and removes the rubber stator material at least partially from inside the housing with the rotation and movement of the head through the housing. The actuator is associated with the at least one blade and is operable to adjust a pivot of the at least one blade relative to the head.

A mud motor includes a rotor and a stator. Drilling fluid received by cavities of the mud motor drives the rotor to rotate within the stator. The rotor includes one or more rotor lobes extending helically and defining a rotor pitch. The stator includes two or more stator lobes extending helically and defining a stator pitch. The rotor and the stator together define a tapered profile of the mud motor that varies proceeding from a top end of the mud motor to a bottom end of the mud motor. At least one of the rotor pitch or the stator pitch vary as proceeding from the top end of the mud motor to the bottom end of the mud motor.

A progressing cavity pump has: a stator; a rotor; the rotor having a first axial operating position within the stator in which a first axial part of the rotor aligns with a first axial part of the stator to form an active pump section adapted to generate a pumping force on rotation of the rotor in the stator; the rotor having a second axial operating position within the stator in which the first axial part of the rotor aligns with a second axial part of the stator to form an active pump section adapted to generate a pumping force on rotation of the rotor in the stator. A related method is disclosed.

The invention relates to a progressive cavity pump, comprising at least: a stator (1); a rotor (2), which rotates in the stator (1); a drive (3); a pump housing (4), which is connected to the stator (1) and has at least one inlet opening or outlet opening for the medium to be conveyed; a connecting shaft (9), which is driven by the drive and rotates centrally about an axis (R) in ideal operation of the pump; a coupling rod (10), which is arranged, for example, in the pump housing (4), is articulated at the drive-side end to the connecting shaft (9) and is articulated at the rotor-side end to the rotor (2), and produces an eccentric motion of the rotor end (7) when the connecting shaft (9) rotates centrally. Said pump is characterized in that at least one sensor (15, 16) is arranged in the region of the connecting shaft (9) in order to detect or measure a deviation from true running, which sensor determines a motion profile of the connecting shaft (9) at a specified angular position of the connecting shaft by virtue of the fact that the distance of the surface of the connecting shaft (9) from the sensor (15, 16) is measured.

An apparatus for removing rubber stator material from inside a housing includes a head, at least one blade, and an actuator. For example, the apparatus can be used to core out rubber material from the housing so new material can be molded therein. Also, the apparatus can be used to cut back excess rubber material newly molded in the housing. The head is rotated about an axis and is moved along the axis relative to the housing. The at least one blade is pivotably connected to the head and removes the rubber stator material at least partially from inside the housing with the rotation and movement of the head through the housing. The actuator is associated with the at least one blade and is operable to adjust a pivot of the at least one blade relative to the head.