Abstract: A stator segment is provided for a helical gear device. The stator segment includes a stator tube and modular stator inserts. The stator tube has an inner profile with at least two internal sides that extend longitudinally along an interior of the stator tube. The modular stator inserts each have an outer profile that substantially matches and fits within the inner profile of the stator tube. The modular stator inserts also each have an interior helical profile that defines a central opening. The modular stator inserts are configured to be removably inserted longitudinally into the stator tube along the inner profile of the stator tube. The inner profile aligns the modular stator inserts to form a continuous helical chamber and prevents rotation of the modular stator inserts relative to the stator tube.

Abstract: A stator segment is provided for a helical gear device. The stator segment includes a stator tube and modular stator inserts. The stator tube has an inner profile with at least two internal sides that extend longitudinally along an interior of the stator tube. The modular stator inserts each have an outer profile that substantially matches and fits within the inner profile of the stator tube. The modular stator inserts also each have an interior helical profile that defines a central opening. The modular stator inserts are configured to be removably inserted longitudinally into the stator tube along the inner profile of the stator tube. The inner profile aligns the modular stator inserts to form a continuous helical chamber and prevents rotation of the modular stator inserts relative to the stator tube.

Abstract: A hybrid elastomer/metal on metal motor for a helical gear device includes a rotor and stator comprising a hydraulic motor that produces work when a working fluid is pumped therethrough. The improvement involves the stator being, for part of its length, a conventional or even wall stator, using an elastomer to form a seal against the moving rotor. The stator's remaining length comprises a profiled rigid surface that forms a seal directly with the moving rotor. This gives the motor the high efficiency of the elastomer sealing against the rotor, and simultaneously provides a backup of the stator's rigid section allowing continued motor operation at reduced efficiency, if the elastomer part failed in service. The invention also includes combinations of a regular disk stack with a rubber lining, a rigid material disk stack (or unitized element) and a circular rigid sleeve which react to rotor sideloading while permitting proper rotor orbiting.

Abstract: A fluid displacement apparatus includes a stator section with a rotor therein. The stator section includes a cylindrical casing, a helically-convoluted chamber section within the cylindrical casing, and a rigid sleeve within the cylindrical casing and separate from the helically-convoluted chamber section. The rigid sleeve includes a circular internal bore. The rotor is rotatably disposed within the cylindrical casing. The rotor includes a helically-lobed section disposed within the helically-convoluted chamber section, and a circular cylinder section disposed within the rigid sleeve. The circular cylinder section provides a fluid passageway between the rigid sleeve and the circular cylinder section. Side loads from the rotor are distributed along a contact line at any point of rotation of the circular cylinder section within the rigid sleeve.

Abstract: A hybrid elastomer/metal on metal motor for a helical gear device includes a rotor and stator comprising a hydraulic motor that produces work when a working fluid is pumped therethrough. The improvement involves the stator being, for part of its length, a conventional or even wall stator, using an elastomer to form a seal against the moving rotor. The stator's remaining length comprises a profiled rigid surface that forms a seal directly with the moving rotor. This gives the motor the high efficiency of the elastomer sealing against the rotor, and simultaneously provides a backup of the stator's rigid section allowing continued motor operation at reduced efficiency, if the elastomer part failed in service. The invention also includes combinations of a regular disk stack with a rubber lining, a rigid material disk stack (or unitized element) and a circular rigid sleeve which react to rotor sideloading while permitting proper rotor orbiting.

Abstract: A hybrid elastomer/metal on metal motor for a helical gear device includes a rotor and stator comprising a hydraulic motor that produces work when a working fluid is pumped therethrough. The improvement involves the stator being, for part of its length, a conventional or even wall stator, using an elastomer to form a seal against the moving rotor. The stator's remaining length comprises a profiled rigid surface that forms a seal directly with the moving rotor. This gives the motor the high efficiency of the elastomer sealing against the rotor, and simultaneously provides a backup of the stator's rigid section allowing continued motor operation at reduced efficiency, if the elastomer part failed in service. The invention also includes combinations of a regular disk stack with a rubber lining, a rigid material disk stack (or unitized element) and a circular rigid sleeve which react to rotor sideloading while permitting proper rotor orbiting.

Abstract: A comparator tool is provided for evaluating the profile of a multi-lobe helical rotor. The comparator tool includes a housing with a first end and a second end and an internal bore extending from the first end to the second end. The internal bore includes a first diameter having nominal clearance for an original equipment manufacturer (OEM)-specified major diameter of the rotor, a second diameter having nominal clearance for an OEM-specified minor diameter of the rotor, and multiple helical grooves corresponding to a number of lobes in the helical rotor. Each of the multiple helical grooves has nominal clearance for an OEM-specified tip diameter of the rotor. The comparator tool slides along the length of the rotor and provides visibility of an interface between a circumference of the rotor and the first end at any place along a length of the rotor.

Abstract: A fluid displacement apparatus includes a stator section with a rotor therein. The stator section includes a cylindrical casing, a helically-convoluted chamber section within the cylindrical casing, and a rigid sleeve within the cylindrical casing and separate from the helically-convoluted chamber section. The rigid sleeve includes a circular internal bore. The rotor is rotatably disposed within the cylindrical casing. The rotor includes a helically-lobed section disposed within the helically-convoluted chamber section, and a circular cylinder section disposed within the rigid sleeve. The circular cylinder section provides a fluid passageway between the rigid sleeve and the circular cylinder section. Side loads from the rotor are distributed along a contact line at any point of rotation of the circular cylinder section within the rigid sleeve.

Abstract: A comparator tool is provided for evaluating the profile of a multi-lobe helical rotor. The comparator tool includes a housing with a first end and a second end and an internal bore extending from the first end to the second end. The internal bore includes a first diameter having nominal clearance for an original equipment manufacturer (OEM)-specified major diameter of the rotor, a second diameter having nominal clearance for an OEM-specified minor diameter of the rotor, and multiple helical grooves corresponding to a number of lobes in the helical rotor. Each of the multiple helical grooves has nominal clearance for an OEM-specified tip diameter of the rotor. The comparator tool slides along the length of the rotor and provides visibility of an interface between a circumference of the rotor and the first end at any place along a length of the rotor.

Abstract: A stator for a helical gear device is formed from multiple rigid disks and support rings bonded to the disks. Each disk forms part of a profile consisting of radially equally spaced or opened lobes which interact with the convex portions of rotor lobes. The disks are arranged into a desired helical configuration and bonded to one another to form a disk stack defining a helically convoluted elongated chamber therein. The support rings are fixed concentrically against respective end disks of the disk stack. The rings are sized with an inside diameter substantially equal to the major diameter of the central aperture defined by the radially extending lobes of the rigid disks. As a rotor rotates and nutates inside the helically convoluted elongated chamber of the stator, it is supported at both ends of the disk stack by the support rings touching the tips of the rotor lobes. Thus the full force of the rotor's operational inertia is not borne by the disks alone, thereby increasing their life.

Abstract: A stator for a helical gear device is formed from multiple rigid disks and support rings bonded to the disks. Each disk forms part of a profile consisting of radially equally spaced or opened lobes which interact with the convex portions of rotor lobes. The disks are arranged into a desired helical configuration and bonded to one another to form a disk stack defining a helically convoluted elongated chamber therein. The support rings are fixed concentrically against respective end disks of the disk stack. The rings are sized with an inside diameter substantially equal to the major diameter of the central aperture defined by the radially extending lobes of the rigid disks. As a rotor rotates and nutates inside the helically convoluted elongated chamber of the stator, it is supported at both ends of the disk stack by the support rings touching the tips of the rotor lobes. Thus the full force of the rotor's operational inertia is not borne by the disks alone, thereby increasing their life.