Torque transmitting and torsion damping apparatus for use in motor vehicles

Abstract

A torsion damping apparatus between the crankshaft of the engine and the input shaft of the change-speed transmission of a motor vehicle has two flywheels one of which is driven by the crankshaft and the other of which drives the input shaft by way of a friction clutch which generates heat. In order to prevent the transfer of heat from the friction clutch to the antifriction bearing between the flywheels, which are rotatable relative to each other against the opposition of a damper, the bearing is at least partially surrounded by a thermal barrier of synthetic plastic, ceramic or metallic material which prolongs the useful life of the bearing and enhances the torsion damping action of the damper. The thermal barrier can constitute or form part of the damper. The bearing can be disposed radially inwardly of the location of engagement between the clutch and the other flywheel and can be cooled by streams of air flowing through an annulus of passages each having a first end disposed radially inwardly of the friction surface of the other flywheel and a larger second end in a second surface of the other flywheel opposite the friction surface. Heat barriers in the other flywheel can alternate with the passages in the circumferential direction of the other flywheel.

Description

BACKGROUND OF THE INVENTIONThe present invention relates to torque transmitting and torsion damping apparatus, especially to improvements in torque transmitting and torsion damping apparatus which can be utilized in motor vehicles to compensate for fluctuations of torque which is transmitted between driving and driven components, particularly between the crankshaft of the internal combustion engine and the input shaft of the change-speed transmission in a passenger car or another motor vehicle.It is already known to provide a torsion damping apparatus, which is installed in a motor vehicle between the crankshaft of the internal combustion engine and the input shaft of the change-speed transmission, with several flywheels which are rotatable relative to each other within certain limits and against the opposition of one or more dampers. Such apparatus are disclosed, for example, in commonly owned copending patent application Ser. No. 669,657 of Oswald Friedmann as well as in several o...

AI Technical Summary

Benefits of technology

An object of the invention is to provide a torsion damping apparatus which can be used in motor vehicles as a superior substitute for heretofore known torsion damping apparatus and is constructed, dimensioned and assembled in such a way that it and its bearing or bearings can stand long periods of use.

The bias of one of the dished springs can exceed the bias of the other dished spring so that the rolling elements of the bearing means are clamped between the two races when the clutch is disengaged in that the second race tends to move axially with reference to the race which rotates with the one flywheel. The force which is required to disengage the clutch and acts axially of the flywheels is opposed by the one dished spring i.e., the force of the one dished spring must be overcome in order to disengage the clutch. The second portions of the rings can further serve as a means for at least substantially sealing the axial ends of the annular space which is defined by the two races of the bearing means and receives the rolling elements.

Problems solved by technology

This can adversely influence the operation and useful life of the bearing, especially if the races of the bearing are directly connected to or in direct contact with the adjacent flywheels.

Nevertheless, such torsion damping apparatus failed to gain popularity in the automotive and other industries, primarily because the useful life of the bearing or bearings between the flywheels is relatively short.

The bearing or bearings are one of the critical elements in these torsion damping apparatus so that their failure after a relatively short interval of use deters the manufacturers of motor vehicles from employing such torsion damping apparatus between the engine and the change-speed transmission.

Nevertheless, and as already stated above, such apparatus failed to gain widespread acceptance due to the short useful life of the bearing or bearings.

The damper or dampers contribute significantly to the initial and maintenance cost of the torque transmitting apparatus.

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