Abstract: A method of transmitting torque through a flexible coupling includes driving a first rotatable member with a second rotatable member, applying an axial force component to the a flexible coupling connecting the first rotatable member and the second rotatable member by changing an axial offset between the first rotatable member and the second rotatable member interconnected by the flexible coupling, reducing one or more of the axial force component and cyclic equivalent stress born by a flexible diaphragm body of the flexible coupling by axially shifting the first end of the flexible diaphragm body relative to one of the interconnected rotatable members, and affixing a splined member to a second end of the flexible coupling, wherein the flexible diaphragm body has an inner diameter that is greater than an inner diameter of the splined member.

Abstract: A process for forming a flexible composite driveshaft includes providing a mandrel having a rigid region and a compressible region, applying fiber tape to the mandrel using automated fiber placement with in-situ laser curing in the rigid region and without in-situ laser curing the compressible region, and compressing the fiber tape and compressible material in the compressible region to form diaphragms that extend radially outward to a diameter that is at least twice the size of a diameter of the composite driveshaft in the rigid region.

Abstract: A process for forming a flexible composite driveshaft includes providing a mandrel having a rigid region and a compressible region, applying fiber tape to the mandrel using automated fiber placement with in-situ laser curing in the rigid region and without in-situ laser curing the compressible region, and compressing the fiber tape and compressible material in the compressible region to form diaphragms that extend radially outward to a diameter that is at least twice the size of a diameter of the composite driveshaft in the rigid region.

Abstract: A method for sensing misalignment of a rotating shaft includes rotating the shaft. A distance from a sensor on the shaft to a first rim of a first coupling mounted to an end of the shaft is sensed as the shaft rotates. A change in the distance from the first sensor to the first rim of the first coupling is determined based on the sensed distance. An angle of the first coupling based on the change in the distance from the first sensor to the first rim of the first coupling during one revolution of the shaft is determined based on the sensed change in the distance from the first sensor to the first rim. An angle of the shaft is determined based on the sensed distance from the first sensor to the first rim of the first coupling representing the sensed change in the distance from the first sensor to the first rim.

Abstract: A process for forming a flexible composite driveshaft includes providing a mandrel having a rigid region and a compressible region, applying fiber tape to the mandrel using automated fiber placement with in-situ laser curing in the rigid region and without in-situ laser curing the compressible region, and compressing the fiber tape and compressible material in the compressible region to form diaphragms that extend radially outward to a diameter that is at least twice the size of a diameter of the composite driveshaft in the rigid region.

Abstract: A coupling includes a diaphragm assembly, a sleeve, a stud, and a ball bearing system. The diaphragm assembly includes a first end, a second end, and an opening extending axially through the diaphragm assembly with the diaphragm assembly also including a first annular diaphragm pair. The sleeve extends into the opening and has a bore. The stud extends at least partially within the bore of the sleeve and within the opening. The ball bearing system is concentric with and radially between the sleeve and the stud with the ball bearing having an outer race adjacent to the sleeve, an inner race adjacent to the stud, and at least two rows of ball therebetween with the outer race having an arced shape when viewed in a circumferential direction to allow for axial movement of the at least two rows of ball bearings relative to the outer race.

Abstract: A flexible drive shaft test arrangement includes a drive end piece arranged along a rotation axis, a driven end piece axially offset from the drive end piece along the rotation axis, and a shell. The shell connects the drive end piece to the driven end piece. The drive end piece end is offset in rotation about the driven end piece to internally load a flexible drive shaft disposed within the shell with torsion. Test stands and methods for testing flexible drive shafts are also disclosed.

Abstract: A method for sensing misalignment of a rotating shaft includes rotating the shaft. A distance from a sensor on the shaft to a first rim of a first coupling mounted to an end of the shaft is sensed as the shaft rotates. A change in the distance from the first sensor to the first rim of the first coupling is determined based on the sensed distance. An angle of the first coupling based on the change in the distance from the first sensor to the first rim of the first coupling during one revolution of the shaft is determined based on the sensed change in the distance from the first sensor to the first rim. An angle of the shaft is determined based on the sensed distance from the first sensor to the first rim of the first coupling representing the sensed change in the distance from the first sensor to the first rim.

Abstract: A flexible shaft includes first and second shaft portions, first and second angular displacement couplings, and an axial displacement coupling generally extending and centered to a rotational axis. The first shaft portion extends between the first angular displacement coupling and the axial displacement coupling. The second shaft portion extends between the axial displacement coupling and the second angular displacement coupling. The axial displacement coupling includes an outer periphery, first wall attached to and extending radially between the first shaft portion and the periphery, and a second wall attached to and extending radially between the second shaft portion and the periphery. The first and second walls are resiliently flexible to facilitate axial displacement between the first and second shaft portions.

Abstract: A flexible coupling includes a flexible diaphragm body having a first end and a second end. A member is fixed to the first end of the flexible diaphragm body. A splined member is fixed to the second end of the flexible diaphragm body. The splined member is configured to shift relative to a rotatable member rotatably fixed thereto in response to axial displacement of rotatable members interconnected by the flexible coupling. The ratio of inner diameter to the outer diameter is selected to allow for packaging the flexible coupling in a confined space.

Abstract: A flexible coupling includes a flexible diaphragm body having a first end and a second end. A member is fixed to the first end of the flexible diaphragm body. A splined member is fixed to the second end of the flexible diaphragm body. The splined member is configured to shift relative to a rotatable member rotatably fixed thereto in response to axial displacement of rotatable members interconnected by the flexible coupling. The ratio of inner diameter to the outer diameter is selected to allow for packaging the flexible coupling in a confined space.

Abstract: A coupling includes a diaphragm assembly, a sleeve, a stud, and a ball bearing system. The diaphragm assembly includes a first end, a second end, and an opening extending axially through the diaphragm assembly with the diaphragm assembly also including a first annular diaphragm pair. The sleeve extends into the opening and has a bore. The stud extends at least partially within the bore of the sleeve and within the opening. The ball bearing system is concentric with and radially between the sleeve and the stud with the ball bearing having an outer race adjacent to the sleeve, an inner race adjacent to the stud, and at least two rows of ball therebetween with the outer race having an arced shape when viewed in a circumferential direction to allow for axial movement of the at least two rows of ball bearings relative to the outer race.

Abstract: A flexible drive shaft test arrangement includes a drive end piece arranged along a rotation axis, a driven end piece axially offset from the drive end piece along the rotation axis, and a shell. The shell connects the drive end piece to the driven end piece. The drive end piece end is offset in rotation about the driven end piece to internally load a flexible drive shaft disposed within the shell with torsion. Test stands and methods for testing flexible drive shafts are also disclosed.

Abstract: A flexible shaft includes first and second shaft portions, first and second angular displacement couplings, and an axial displacement coupling generally extending and centered to a rotational axis. The first shaft portion extends between the first angular displacement coupling and the axial displacement coupling. The second shaft portion extends between the axial displacement coupling and the second angular displacement coupling. The axial displacement coupling includes an outer periphery, first wall attached to and extending radially between the first shaft portion and the periphery, and a second wall attached to and extending radially between the second shaft portion and the periphery. The first and second walls are resiliently flexible to facilitate axial displacement between the first and second shaft portions.

Abstract: A mechanical shaft includes a shaft body defining a longitudinal axis. A spline is included at a first end of the shaft body. A flexible coupling is included at a second end of the shaft body opposite the spline across the longitudinal axis. The spline and flexible coupling are of dissimilar metals. A bi-metallic joint joins the dissimilar metals together.

Abstract: A flexible coupling includes a flexible diaphragm body having a first end and a second end. A member is fixed to the first end of the flexible diaphragm body. A splined member is fixed to the second end of the flexible diaphragm body. The splined member is configured to shift relative to a rotatable member rotatably fixed thereto in response to axial displacement of rotatable members interconnected by the flexible coupling. The ratio of inner diameter to the outer diameter is selected to allow for packaging the flexible coupling in a confined space.