Two-mass flywheel with a speed-adaptive absorber

Details Two-mass flywheel with a speed-adaptive absorber Two-mass flywheel with a speed-adaptive absorber

1999-07-01

2001-08-28

Browne, Lynne H. (Department: 3629)

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

Speed responsive device for adjusting relative rotational...

Pivoted weight

C464S068800, C074S574300

Reexamination Certificate

active

06280330

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a flywheel of the type having a first rotating ring that is connectible to a drive shaft and a second rotating ring that is connectible to a driven shaft. The first and the second rotating rings are twistable relative to one another and are supported concentrically one inside the other. A torsion spring is located between the first and the second rotating rings to suppress torsional vibrations.
BACKGROUND INFORMATION
A flywheel of this type is described in the German patent 36 21 997 A1.
Such a flywheel, divided into two parts, which is also known as a two-mass flywheel, is used, for example, to isolate vibrations in the drive train of a motor vehicle.
The disadvantage of a flywheel such as is described in DE 36 21 991 A1 is its great weight, which is essentially determined by the two rotating rings. In order to make it possible to achieve good vibrational isolation using the two-mass flywheel, the second rotating ring mounted on the gearing side is considerably heavier than the first rotating ring on the engine side.
The German patent 196 31 989 C1 describes a speed-adaptive dynamic-vibration absorber. It includes a hub part, upon which are located a number of inertial masses, adjacent in the circumferential direction, that are supported in each case in two mounting supports adjacent in the circumferential direction. These include bolts that can roll in such a way on oppositely curved paths of the inertial-mass elements and of the hub part that, in response to the introduction of torsional vibrations superimposed on a rotational motion, a decrease results in the distance of the inertial-mass elements from the axis in the course of curved paths of motion.
SUMMARY OF THE INVENTION
An object of the present invention is to reduce the weight of a two-mass flywheel and, in particular, to permit a lighter type of construction of a drive train.
This objective is achieved in a flywheel of the type noted above by securing a speed-adaptive absorber to the second rotating ring, the speed-adaptive absorber including at least one hub part that is rotatable about the axis of rotation, as well as a plurality of damper masses which are able to swivel at least in the circumferential direction about swivel axes that are set apart from the axis of rotation.
The speed-adaptive damper provided at the second rotating ring makes it possible to reduce torsional vibrations which occur at shafts of periodically operating machines, e.g., at the crank shaft of a combustion engine, and which are superimposed on the rotational motion. A damper is designated as speed-adaptive when it is able to cancel the torsional vibrations over a greater speed range, ideally over the entire speed range of the machine. The principle underlying the absorber is that, upon introduction of a rotary motion, the damper masses endeavor to circle the axis at the greatest possible distance due to centrifugal force. Torsional vibrations which are superimposed on the rotary motion lead to a relative movement of the damper masses inwardly in the radial direction, which is utilized for the dynamic-vibration absorption. The dynamic-vibration absorber has a natural frequency which is proportional to the speed of rotation, so that torsional vibrations having frequencies which are proportional to the speed of rotation are able to be canceled over a large rotational-speed range.
Surprisingly however, due to the arrangement of a speed-adaptive absorber at or on the second rotating ring of a two-mass flywheel, the flywheel can have a considerably lighter design. The attainable savings in weight is attributable primarily to the fact that the arrangement of the present invention makes it possible to achieve an improvement in the vibration response, although the second rotating ring is substantially lighter. However, due to other technical requirements, for example, for reasons of heat absorption and dissipation, the mass of the second rotating ring cannot be reduced arbitrarily. A further advantage of the invention is that materials different from those used till now can be utilized for the second rotating ring. Because the second rotating ring can be made of sheet metal, for example, production costs for the flywheel can be reduced.
The absorber is advantageously mounted on the output side (i.e., the power take-off side)of a prime mover or driven machine.
Good dynamic-vibration absorption is attained because the absorber is arranged on the front end of the flywheel opposite the output.
The arrangement of a coupling driving disk with a pressure plate between the second rotating ring and the absorber permits a particularly compact and space-saving type of construction.
The construction is simplified by providing a pressure spring which acts on the pressure plate and is braced against the absorber.
According to one particularly advantageous refinement, each absorber mass is supported in the hub part by two bolts that are set apart from each other in the circumferential direction and extend parallel to the axis of rotation. The bolts are able to roll on curved paths which, in the region of the hub part, have a profile that is open in a U-shape in the direction of the axis of rotation, and in the area of the absorber masses, have a profile that is open in a U-shape in the opposite direction. The bolts are guided through a guideway on the sides facing away from the respective curved paths. A particularly simple and stable construction is achieved by mounting the absorber masses on bolts which roll on curved paths of the hub part and of the absorber mass.
The noise characteristic is improved because the guideway is made of a damping layer composed of a polymer material.
The damping capacity is particularly good when the damping layer is made of an elastomer material.
The damping layer advantageously ends, in the circumferential direction on both sides, in stop faces which limit the circumferential mobility of the bolts to a fixed value.
Production is simplified and reduced in cost because the curved paths form a component of inserts.
The inserts and the damping layers advantageously form a component of insertion parts which are immovably accommodated in openings of the hub part and of the absorber masses.
Production is also simplified because, after the insertion of the inserts into the openings, the material member forming the damping layer is directly joined to the openings and the inserts, forming a solid bond.
It is only necessary to place small demands on the manufacturing tolerances if a free space is provided between the absorber mass or hub and the inserts, and the free space is filled with the material of the damping layer and forms a tolerance-adjustment layer.
If the tolerance-adjustment layer and the damping layer are configured integrally and continuously with one another, they can be produced in one work step.
The inserts can be inexpensively produced by extrusion.


REFERENCES:
patent: 4171029 (1979-10-01), Beale
patent: 4732250 (1988-03-01), Maucher et al.
patent: 5697845 (1997-12-01), Curtis
patent: 5884735 (1999-03-01), Eckel et al.
patent: 6095304 (2000-08-01), Eckel
patent: 6109134 (2000-08-01), Sudau
patent: 36 21 991 (1988-01-01), None
patent: 36 21 997 (1988-01-01), None
patent: 196 31 989 (1997-09-01), None
patent: 1490-346 (1989-06-01), None

Affiliated with

Also associated with

Rating

Two-mass flywheel with a speed-adaptive absorber does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Two-mass flywheel with a speed-adaptive absorber, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two-mass flywheel with a speed-adaptive absorber will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2441304