Method of assembling tubular shaft assemblies
AssigneeGeneral Motors Corporation
InventorsPhilip D. Arnold, Roy G. Kaywood
Life of this patent
Estimating the term…
Abstract
Camshaft assemblies, methods and apparatus are provided for making camshafts by the expansion of tubular shafts into prelocated cams, journals and other elements, if desired. Features of the camshafts include trilobe or polylobe element openings, preferably splined or serrated for low energy filling and high torque capacity and High Strength Low Alloy mild steel tubular shaft material. The method emphasizes trapping, or loading, the shaft of prevent axial lengthening during expansion such as by mechanical ballizing. The apparatus includes adjustable thrust blocks and locating plungers with incorporated flush pin gages together with hydraulic or other loading means all for use in carrying out the assembly method with various benefits from the incorporated features.
Claims14
A method of manufacturing a camshaft assembly said method including the steps of:
- providing a plurality of cam and journal elements formed to final dimensions except for finish grinding, said elements each including an axial opening,
- securing said elements in predetermined fixed orientation and spacing with said openings aligned on a common axis,
- inserting an essentially straight hollow tube having opposite ends into said elements in close fitting relation with said openings,
- longitudinally restraining one end of the tube while providing diametral clearance around portions adjacent said elements,
- longitudinally loading the other end of the tube to prevent elongation thereof
- expanding the hollow tube into mechanical interference engagement with all the element openings and radially outward thereof adjacent the elements to secure the elements permanently onto the shaft in said predetermined orientation and spacing while forming within the tube a uniform smooth sided interior cross-sectional configuration, by forcing through the tube in a direction toward said restrained one end an expanding element sufficiently larger than the tube inner diameter to outwardly deform the tube wall in the required degree, and
- finish grinding the outer surfaces of the cam and journal elements.
A method of manufacturing a camshaft assembly, said method including the steps of:
- providing a plurality of cam and journal elements, said elements each including an axial opening,
- securing said elements in predetermined fixed orientation and spacing with said openings aligned on a common axis,
- inserting an essentially straight hollow tube having opposite ends into said elements in close fitting relation with said openings,
- longitudinally restraining one end of the tube while providing diametral clearance around portions adjacent said elements,
- longitudinally loading the other end of the tube to prevent elongation thereof
- expanding the hollow tube into mechanical interference engagement with all the element openings and diametrically outward thereof adjacent the elements to secure the elements permanently onto the shaft in said predetermined orientation and spacing by forcing through the tube an expander element sufficiently larger than the tube inner diameter to outwardly deform the tube wall in the required degree.
A method of manufacturing a tubular shaft assembly, said method including the step of:
- providing a plurality of elements for attachment to a tubular shaft, said elements each including an axial opening,
- securing said elements in fixed orientation and spacing with said openings aligned on a common axis,
- inserting an essentially straight hollow tube having opposite ends into said elements in close fitting relation with said openings, longitudinally restraining one end of the tube while providing diametral clearance around portions adjacent said elements, longitudinally loading the other end of the tube to prevent elongation thereof, and
- expanding the hollow tube into mechanical interference engagement with all the element openings to secure the elements permanently onto the shaft in said fixed orientation and spacing by forcing through the tube an expander element sufficiently larger than the tube inner diameter to outwardly deform the tube wall in the required degree.
Dependencies are inferred from the claim text.