Abstract: A gerotor device includes a valving plate, a balancing plate structure, and a rotor positioned between the valving plate and the balancing plate structure. High pressure fluid flowing from the valving plate toward the rotor pushes the rotor toward the balancing plate structure. The balancing plate structure includes a balancing plate and a second plate. A cavity is defined between the balancing plate and the second plate. The balancing plate includes a fluid passage having a check valve and fluid passes through the fluid passage for pressuring the cavity. The balancing plate includes first and second relief holes extending through the balancing plate connected with the cavity.

Abstract: A gerotor device includes a rotor having outwardly extending teeth and a stator having inwardly extending teeth. The inwardly extending teeth are formed by rollers each of which is received in a respective roller pocket in the stator. Each roller pocket has a maximum pocket width measured perpendicular to a pocket centerline. Each roller pocket defines a roller bearing surface having a first side that follows a first radius and a second side on an opposite side of the centerline that follows a second radius. Each radius is greater than ½ the maximum pocket width. Each roller pocket has an edge pocket width between a first pocket edge where the pocket transitions to a generally cylindrical section in the stator and a second pocket edge on an opposite side of the centerline. The edge pocket width is less than the maximum pocket width.

Abstract: A method for manufacturing roller pockets in a stator of a gerotor device generally includes providing a stator having a cavity including a generally cylindrical section defining a central axis and a plurality of roller pockets angularly spaced around a periphery of the cylindrical section. Each roller pocket is configured to receive a respective roller, which acts as an internal tooth of the gerotor device. Each roller pocket defines a generally cylindrical roller pocket bearing surface. The method further includes grinding each roller pocket bearing surface of each roller pocket with a grinding wheel rotating about a rotational axis perpendicular to the central axis. A stator for a gerotor device is also described.

Abstract: A method for deburring a ground metal part includes loading a ground metal part into a carrier, contacting a first planar surface of the ground metal part with a first grinding wheel, and contacting a second planar surface of the ground metal part with a second grinding wheel. The first grinding wheel is rotated in a first rotational direction. The second grinding wheel is rotated also in the first rotational direction. After the first grinding wheel is rotated in the first rotational direction, the first grinding wheel is then rotated in a second rotational direction, which is opposite to the first rotational direction. After the second grinding wheel is rotated in the first rotational direction, the second grinding wheel is also rotated in the second rotational direction.

Abstract: A parts carrier assembly for a grinding machine includes an annular parts carrier and a bearing insert. The annular parts carrier includes an upper surface, a lower surface, an inner edge, an outer edge, and a plurality of loading apertures. The inner edge is configured to engage a driving wheel of the grinding machine. The driving wheel rotates about a central axis resulting in rotation of the parts carrier about an offset axis, which is offset from the central axis. The loading apertures are configured to receive parts to be ground by the grinding machine. The bearing insert includes an inner bearing surface complementary in shape to the outer edge of the parts carrier. The outer surface the parts carrier bears against the inner bearing surface of the bearing insert as the parts carrier rotates about the offset axis.

Abstract: A method for deburring a ground metal part includes loading a ground metal part into a carrier, contacting a first planar surface of the ground metal part with a first grinding wheel, and contacting a second planar surface of the ground metal part with a second grinding wheel. The first grinding wheel is rotated in a first rotational direction. The second grinding wheel is rotated also in the first rotational direction. After the first grinding wheel is rotated in the first rotational direction, the first grinding wheel is then rotated in a second rotational direction, which is opposite to the first rotational direction. After the second grinding wheel is rotated in the first rotational direction, the second grinding wheel is also rotated in the second rotational direction.

Abstract: A gerotor device includes a valving plate, a balancing plate structure, and a rotor positioned between the valving plate and the balancing plate structure. High pressure fluid flowing from the valving plate toward the rotor pushes the rotor toward the balancing plate structure. The balancing plate structure includes a balancing plate and a second plate. A cavity is defined between the balancing plate and the second plate. The balancing plate includes a fluid passage having a check valve and fluid passes through the fluid passage for pressuring the cavity. The balancing plate includes first and second relief holes extending through the balancing plate connected with the cavity.

Abstract: A hydraulic pump includes a housing (12), a cylinder block (14), a plurality of pistons (16), a swash plate (18), a trunnion arm (22), a first biasing assembly (54), and a second biasing assembly (56). The cylinder block includes a plurality of piston chambers. The swash plate is disposed for pivotal movement in the housing and cooperates with the pistons to vary the working volume of the piston chambers. The swash plate is pivotal about a pivot axis (80). The trunnion arm includes a cylindrical shaft portion (140) and a cam portion (142) connected with or integrally formed with the shaft portion. The trunnion arm is operatively connected with the swash plate for controlling pivotal movement of the swash plate. The cylindrical shaft portion defines a trunnion arm rotational axis (144) that is parallel to and offset from the pivot axis (80).

Abstract: A method for manufacturing roller pockets in a stator of a gerotor device generally includes providing a stator having a cavity including a generally cylindrical section defining a central axis and a plurality of roller pockets angularly spaced around a periphery of the cylindrical section. Each roller pocket is configured to receive a respective roller, which acts as an internal tooth of the gerotor device. Each roller pocket defines a generally cylindrical roller pocket bearing surface. The method further includes grinding each roller pocket bearing surface of each roller pocket with a grinding wheel rotating about a rotational axis perpendicular to the central axis. A stator for a gerotor device is also described.

Abstract: A grinding wheel dressing assembly includes a driving gear rotatable about a central axis and a dressing ring engaged with the driving gear. Rotation of the driving gear about the central axis results in rotation of the dressing ring about an offset axis, which is offset from the central axis. The dressing ring includes a contact surface generally normal to the offset axis and adapted to remove dull CBN particles from a substantially planar grinding surface of a grinding wheel that comes into contact with the contact surface.

Abstract: A hydraulic motor having a cooling system includes a stator, a rotor that rotates and orbits in the stator, a drive link connected to the rotor, and a housing connected with the stator. The housing includes a working fluid inlet port, a working fluid outlet port, a cooling fluid inlet port, and a cooling fluid outlet port. Each port extends through the housing and is configured to connect with a different associated external fluid line. Pressurized fluid enters the working fluid inlet port to rotate and orbit the rotor en route to the working fluid outlet port. The cooling fluid ports are isolated from the working fluid inlet port and the working fluid outlet port within the housing.

Abstract: A gerotor device includes a rotor having outwardly extending teeth and a stator having inwardly extending teeth. The inwardly extending teeth are formed by rollers each of which is received in a respective roller pocket in the stator. Each roller pocket has a maximum pocket width measured perpendicular to a pocket centerline. Each roller pocket defines a roller bearing surface having a first side that follows a first radius and a second side on an opposite side of the centerline that follows a second radius. Each radius is greater than ½ the maximum pocket width. Each roller pocket has an edge pocket width between a first pocket edge where the pocket transitions to a generally cylindrical section in the stator and a second pocket edge on an opposite side of the centerline. The edge pocket width is less than the maximum pocket width.

Abstract: A method for manufacturing roller pockets in a stator of a gerotor device generally includes providing a stator having a cavity including a generally cylindrical section defining a central axis and a plurality of roller pockets angularly spaced around a periphery of the cylindrical section. Each roller pocket is configured to receive a respective roller, which acts as an internal tooth of the gerotor device. Each roller pocket defines a generally cylindrical roller pocket bearing surface. The method further includes grinding each roller pocket bearing surface of each roller pocket with a grinding wheel rotating about a rotational axis perpendicular to the central axis. A stator for a gerotor device is also described.

Abstract: A grinding wheel dressing assembly includes a driving gear rotatable about a central axis and a dressing ring engaged with the driving gear. Rotation of the driving gear about the central axis results in rotation of the dressing ring about an offset axis, which is offset from the central axis. The dressing ring includes a contact surface generally normal to the offset axis and adapted to remove dull CBN particles from a substantially planar grinding surface of a grinding wheel that comes into contact with the contact surface.

Abstract: A parts carrier assembly for a grinding machine includes an annular parts carrier and a bearing insert. The annular parts carrier includes an upper surface, a lower surface, an inner edge, an outer edge, and a plurality of loading apertures. The inner edge is configured to engage a driving wheel of the grinding machine. The driving wheel rotates about a central axis resulting in rotation of the parts carrier about an offset axis, which is offset from the central axis. The loading apertures are configured to receive parts to be ground by the grinding machine. The bearing insert includes an inner bearing surface complementary in shape to the outer edge of the parts carrier. The outer surface the parts carrier bears against the inner bearing surface of the bearing insert as the parts carrier rotates about the offset axis.

Abstract: A grinding wheel dressing assembly includes a driving gear rotatable about a central axis and a dressing ring engaged with the driving gear. Rotation of the driving gear about the central axis results in rotation of the dressing ring about an offset axis, which is offset from the central axis. The dressing ring includes a contact surface generally normal to the offset axis and adapted to remove dull CBN particles from a substantially planar grinding surface of a grinding wheel that comes into contact with the contact surface.

Abstract: A method for manufacturing roller pockets in a stator of a gerotor device generally includes providing a stator having a cavity including a generally cylindrical section defining a central axis and a plurality of roller pockets angularly spaced around a periphery of the cylindrical section. Each roller pocket is configured to receive a respective roller, which acts as an internal tooth of the gerotor device. Each roller pocket defines a generally cylindrical roller pocket bearing surface. The method further includes grinding each roller pocket bearing surface of each roller pocket with a grinding wheel rotating about a rotational axis perpendicular to the central axis. A stator for a gerotor device is also described.

Abstract: A hydraulic motor having a cooling system includes a stator, a rotor that rotates and orbits in the stator, a drive link connected to the rotor, and a housing connected with the stator. The housing includes a working fluid inlet port, a working fluid outlet port, a cooling fluid inlet port, and a cooling fluid outlet port. Each port extends through the housing and is configured to connect with a different associated external fluid line. Pressurized fluid enters the working fluid inlet port to rotate and orbit the rotor en route to the working fluid outlet port. The cooling fluid ports are isolated from the working fluid inlet port and the working fluid outlet port within the housing.

Abstract: The present disclosure relates to a hydraulic transmission assembly for a ground vehicle comprises a pump unit and a hydraulic motor assembly connected to the pump unit. The pump unit includes a driven shaft configured to operably connect to a motor of the ground vehicle. The hydraulic motor assembly includes a motor housing configured to rotatably mount to a wheel assembly of the ground vehicle. The housing has a central opening. A stationary output shaft has a first end section received in the central opening and a second end section configured to rigidly attach to a frame of the ground vehicle. The output shaft includes at least one internal fluid passage in fluid communication with at least one fluid passage of the pump unit. Pressurization of the hydraulic motor assembly via the pump unit rotates the motor housing relative to the stationary output shaft which, in turn, rotates the wheel assembly in one of a first direction and second direction.

Abstract: A hydraulic motor having a cooling system includes a stator, a rotor that rotates and orbits in the stator, a drive link connected to the rotor, and a housing connected with the stator. The housing includes a working fluid inlet port, a working fluid outlet port, a cooling fluid inlet port, and a cooling fluid outlet port. Each port extends through the housing and is configured to connect with a different associated external fluid line. Pressurized fluid enters the working fluid inlet port to rotate and orbit the rotor en route to the working fluid outlet port. The cooling fluid ports are isolated from the working fluid inlet port and the working fluid outlet port within the housing.