Method of forming damped drive shafts

Details Method of forming damped drive shafts Method of forming damped drive shafts

2000-05-17

2002-04-16

Hughes, S. Thomas (Department: 3726)

Metal working

Method of mechanical manufacture

Utilizing transitory attached element or associated separate...

C138S089000, C464S180000

Reexamination Certificate

active

06370756

ABSTRACT:

This invention relates to a method of forming a damped drive shaft of the kind adapted to transmit driving torque from a vehicle transmission to the driving wheels. More particularly the invention relates to such a shaft. whose ends are radially contracted.
BACKGROUND OF THE INVENTION
In those instances in which a vehicle has a tubular drive shaft which couples the transmission to its driving wheels it is not uncommon for rotation of the shaft to produce objectionable vibrations and noise. These undesirable characteristics may be reduced by fitting a damper into the shaft. The damper, however, must be of such diameter and construction that, once it occupies a selected position in the shaft it will remain in such position thereby avoiding unbalancing the shaft because of movement of the damper relative to the shaft. The fitting of a damper to a drive shaft presents special problems in those instances in which the drive shaft has a larger diameter between its ends than at its ends. However, the use of reduced diameter end drive shafts is preferred in many instances.
Obviously, if a damper is to be assembled in a shaft whose ends are of smaller diameter than the remainder of the shaft, and if the damper is to remain fixed in a selected position within the shaft, problems are encountered in inserting the damper into the shaft through the reduced diameter at one end of the shaft. One manner of overcoming these problems is disclosed in U.S. Pat. No. 5,868,627.
It also is possible to insert a damper into a shaft before the ends are contracted and thereafter reduce the diameter of the ends of the shaft by a swaging operation. In this instance it is necessary to wash the ends of the shaft so as to remove the swaging compound. If the damper is made of paperboard or other hygroscopic material, care must be taken to ensure that the washing of the shaft does not impair the integrity of the damper. One manner of achieving this result is disclosed in U.S. Pat. No. 5,976,021.
Although the constructions and methods disclosed in the aforementioned patents enable satisfactory results to be obtained, it is desirable to minimize manufacturing complexities and assembly operations. A damped shaft formed in accordance with this invention enables this result to be achieved.
SUMMARY OF THE INVENTION
A damped shaft is formed according to a preferred embodiment of the invention from a metal tube of suitable length and of substantially uniform diameter from end to end. Before either end of the tube is contracted radially, a cylindrical damper of appropriate diameter is inserted into the tube and located in a position inwardly of both ends of the tube. Thereafter, a plug formed of deformable material is fitted into each end of the tube. Each plug has an undeformed size or diameter corresponding substantially to the diameter of the tube. The plugs are so positioned in the tube that they do not engage the damper, but instead are axially spaced therefrom.
Following the insertion of the plugs into the opposite ends of the tube-the ends are radially contracted by a swaging operation. As the ends of the tube contract, they radially contract the plugs, thereby enabling the plugs to seal the tube at its opposite ends.
Following the swaging operation the ends of the tube may be finished by a facing or chamfering operation and washed. Since the plugs seal the ends of the tube neither the washing liquid nor chips from the finishing operation may reach the damper.
Each of the plugs has a rod which extends axially of the plug and terminates at one end in an eye through which a hook may extend to enable the plug to be extracted from the associated end of the tube.
Following removal of the plugs, the shaft may be balanced.


REFERENCES:
patent: 1895827 (1933-01-01), Van Hecke
patent: 2493452 (1950-01-01), Grigg
patent: 2924246 (1960-02-01), Markel
patent: 3704729 (1972-12-01), Tomlinson
patent: 3910191 (1975-10-01), Williams
patent: 3983904 (1976-10-01), Laviano
patent: 4014184 (1977-03-01), Stark
patent: 4503880 (1985-03-01), Hochman
patent: 4762152 (1988-08-01), Clausen
patent: 4964438 (1990-10-01), Welty
patent: 4968197 (1990-11-01), Chen
patent: 5033510 (1991-07-01), Huber
patent: 5461777 (1995-10-01), Ikeda et all.
patent: 5560396 (1996-10-01), Kramer, Jr.
patent: 5643093 (1997-07-01), Breese
patent: 5816292 (1998-10-01), Wilson et al.
patent: 5868627 (1999-02-01), Stark et al.
patent: 5976021 (1999-11-01), Stark et al.
patent: 6254488 (2001-03-01), Hill

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