Progressive Cavity Pump/Motor Drive Mechanism
AssigneeRoper Pump Company
InventorJohn Eugene Purcell
Life of this patent
Estimating the term…
Abstract
A progressing cavity pump has a rotor that moves in an eccentric motion, and is driven by a drive shaft that rotates about a fixed axis. Various means have been used to connect the two; mostly using an intermediate shaft called a connecting rod that has a universal joint at either end. This device replaces that with two parallel plates; one with several pins protruding from it, and the other with the same number of holes in it. The holes are sized to allow the eccentric motion of the rotor. There is also a ball between the two plates to transmit loads between the plates.
Claims19
A drive coupling mechanism, comprising:
- a first plate configured to couple to a shaft having a fixed axis;
- a second plate eccentrically disposed adjacent to and spatially separate from the first plate, the second plate configured to attach to a rotor having an orbiting axis, wherein a rotation of the rotor produces a circular path of the orbiting axis with a diameter of eccentricity;
- one of said first plate and said second plate including a first cylindrical bore wall defining a first bore extending longitudinally towards the other one of said first plate and said second plate;
- a first pin having a first end attached to said other one of said first plate and said second plate, said first pin extending into said first bore and abutting the first cylindrical bore wall, said first pin having a pin diameter, said first bore having a bore diameter, said bore diameter being at least equal to the pin diameter plus the diameter of eccentricity of the orbiting axis to allow rotation of the rotor and the shaft via the drive coupling mechanism.
A method for coupling a shaft having a fixed axis to a rotor having an orbiting axis, wherein a rotation of the rotor produces a circular path of the orbiting axis with a diameter of eccentricity, the method comprising:
- attaching a first pin to a first plate, with the first pin extending perpendicularly from the first plate, the first pin having a pin diameter, a first end and a second end opposite the first end, with the first end being attached to the first plate;
- placing a second plate adjacent to and spatially separate from the first plate, the second plate having a first cylindrical bore wall defining a first bore that extends longitudinally towards the first plate, the first bore having a bore diameter that is at least equal to the pin diameter plus the diameter of eccentricity of the orbiting axis;
- depositing the first pin into the first bore and abutting the first cylindrical bore wall of the second plate while maintaining a spatial separation between the first plate and the second plate;
- fixedly securing one of the first plate and the second plate to the shaft having the fixed axis;
- and
- fixedly securing the other one of the first plate and the second plate to the rotor having the orbital axis, the shaft and the rotor being coupled via a drive coupling mechanism including the first plate, the second plate and the first pin to allow rotation of the rotor and the shaft via the drive coupling mechanism.
Dependencies are inferred from the claim text.