Cross member for a universal joint for high torque loads

Details Cross member for a universal joint for high torque loads Cross member for a universal joint for high torque loads

1999-06-28

2001-05-01

Browne, Lynne H. (Department: 3629)

Rotary shafts, gudgeons, housings, and flexible couplings for ro

Coupling accommodates drive between members having...

Coupling transmits torque via radially directed pin

Reexamination Certificate

active

06224489

ABSTRACT:

CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority upon German application 198 31 143.5 filed Jul. 11, 1998, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to a cross member for a universal joint. The cross member includes a base member arranged at the center of the cross member. Four arms project from the base member and extend away from the center. Opposing arm pairs define a common axis. The axes intersecting one another in the center of the universal joint at a right angle. Each arm includes a cylindrical running face to receive rolling contact members of a rolling contact bearing. Each running face is arranged concentrically around its respective axis. The base member, in the region of transition to an arm, includes an annular and radially extending shoulder. The shoulder is arranged co-axially around the respective axis.
DE-OS 27 21 706 describes a cross member for a universal joint. Here, the arms each change step-like into the annular shoulder of the base member. Universal joints of this type are primarily used in driveshafts. Two universal joints are connected in a rotationally fast way by telescopically connected shaft portions. At its input end and at its output end, the universal joint includes a joint yoke. The joint yokes are connected to one another in a rotationally fast way by the cross member. The arms of the cross member are supported in rolling contact bearing bushes which are accommodated in bores in the joint yokes. The torque transmitting ability of a universal joint is largely determined by the design of the joint yokes, the cross member and the bearings. In particular, the torque transmitting ability is limited by the strength of the highly loaded transition regions between the arm running faces and the base member. This may result in disadvantages and problems, especially in heavy-duty joints used in rolling mill drives.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a cross member of the initially mentioned type which, while retaining its external dimensions, can be subjected to higher torque loads when used in universal joints.
In accordance with the invention, each arm includes a transition region between the running face and the base member. The transition region outer face extends curve-like with a continuously increasing diameter and with a decreasing radius of curvature relative to the respective shoulder of the base member. Viewing a sectional plane extending between the axes of the arms, a distance exists between a first tangent on the outer face arm transition region and a second tangent which extends parallel to the first tangent. The first tangent extends at a 45° angle relative to the axis of the respective arm. The second tangent, viewed from the center, is positioned behind the first tangent and is positioned on the outer face of the base member at a point located on a line of symmetry of the cross member. The line of symmetry extends at an angle of 45° relative to the axis of the respective arm. The distance corresponds to {fraction (1/10)} of the smallest radius of the respective arm. The arms are induction-hardened. The hardness run-out occurs in the region of the shoulder of the base member. This region is subjected to low stresses when the cross member is in operation. Thus, it is possible to provide a low notch curve in the transition region between the bearing face and the base member. This achieves a high torque transmitting capacity of the cross member. In addition, the arms of the cross member are induction-hardened beyond the curve of the transition region. Accordingly, it is possible to avoid metallurgical notches inside the transition region which is subjected to high loads during operation. The hardness run-out occurs in a low-stress region of the shoulder. Further, required strength values can also be achieved in great depths below the surface of the workpiece by induction-hardening.
To achieve an adequate seat face length for a sealing ring in the transition region, arm transition regions can end in the respective shoulder of the base member, each forming an annular indentation.
A reduction in diameter in the region adjoining the running face of an arm between the running face and the transition region provides a grinding run-out. The grinding run-out facilitates the production of the cross member.
The torque bearing capacity of the cross member is increased even further by producing the cross member from a quenched and tempered chromium nickel steel.
From the following detailed description, taken in conjunction with the accompanying drawings and subjoined claims, other objects and advantages of the present invention will become apparent to those skilled in the art.


REFERENCES:
patent: 1093822 (1914-04-01), Blum
patent: 4371358 (1983-02-01), Laue
patent: 4634401 (1987-01-01), Mueller et al.
patent: 4758203 (1988-07-01), Breazeale et al.
patent: 4925430 (1990-05-01), Heier
patent: 299721 (1972-06-01), None
patent: 1 955 010 (1970-12-01), None
patent: 26 36 752 A1 (1977-04-01), None
patent: 27 21 706 A1 (1977-11-01), None
patent: 35 09 469 A1 (1985-10-01), None
patent: 31 11 145 C2 (1986-12-01), None
patent: 38 18 330 A1 (1989-12-01), None
patent: 972516 (1964-10-01), None
patent: 61-270524 (1986-11-01), None
patent: 64-39321 (1989-02-01), None
patent: 889936 (1964-10-01), None
Machinery's Handbook, 25th ed. New York, International Press, pp 506 & 507.TJ151.M3 1996.*
Mancuso , J., Couplings and Joints, N.Y., Marcel Dekker, pp 392-399. TJ183.M36 1999.

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