WO1999045286A1

WO1999045286A1 - Antifriction bearing with disk-like cage for a flywheel

Info

Publication number: WO1999045286A1
Application number: PCT/EP1998/007898
Authority: WO
Inventors: Werner Oberbeckmann
Original assignee: INA Wälzlager Schaeffler oHG
Priority date: 1998-03-04
Filing date: 1998-12-04
Publication date: 1999-09-10
Also published as: DE19809176A1

Abstract

A flywheel consists of two flywheel masses (1, 2) which can rotate in relation to each other to a limited extent and between which an antifriction bearing (3) is arranged. The antifriction bearing (3) is configured as a single-groove grooved ball bearing whose outer race (12) is formed by two half rings (27, 28) positioned at an axial distance to each other in such a way that a peripheral slot (29) is created. A freely rotating disk-like cage (30) is guided in said slot (29). In this way the disk-like cage (30) is prevented from moving out of the bearing (3) in the axial direction. The invention also provides for recesses (34) on the lateral surface of the two half rings (27, 28) which serve as a temperature barrier in the form of an insulating air cushion.

Description

BEARING WITH DISC CAGE FOR A FLYWHEEL

Field of application of the invention

The invention relates to a flywheel, in particular for internal combustion engines, with two flywheels that can be rotated relative to one another to a limited extent, between which a roller bearing is arranged, the outer bearing ring of which is arranged in a cylindrical bore of the second flywheel mass and the inner bearing ring of which is arranged on a cylindrical collar of the first flywheel mass, wherein a sheet metal part is arranged between the outer bearing ring and the second flywheel mass, which surrounds the rolling bearing on one end face with an axially outwardly directed formation, so that a cavity is formed, while the rolling bearing on its other end face by means of a reinforcing ring and molded sealing areas existing sealing ring is sealed.

Background of the Invention

A flywheel of this type is previously known from DE 42 14 655 A1. This between the outer bearing ring and the second flywheel shaped sheet metal part limits with its axially outward shaping a cavity that serves to receive bearing lubricant, so that this additional lubricant chamber ensures that the bearing can be properly lubricated over a longer period of time. The disadvantage here is that due to the high thermal conductivity of the molded sheet metal part, there is no thermal insulation between the components involved, so that the lubricant filling of the bearing may be overstressed by the heat flow directed inwards from the outside. In extreme cases, excessive thermal distortion of the bearing could occur, so that its function appears to be at risk. 2

The deep groove ball bearing arranged between the two centrifugal masses can now be designed in different ways. Is it spherical, d. H. Executed without a cage, the outer bearing ring must be blown up to fill the bearing with balls. If a snap cage is used, there is a risk that it can migrate out of the bearing if it is not properly installed. If, on the other hand, a window cage is used, it must first be made in two pieces and connected to a unit during assembly.

Summary of the invention

The invention has for its object to design a bearing for two rotating masses rotatable relative to each other so that it has a high level of functional reliability and is inexpensive to produce.

According to the invention this object is achieved according to the characterizing part of claim 1 in that the outer bearing ring consists of two race halves spaced apart from one another in the axial direction, so that a circumferential gap is formed in which a freely rotatable disc cage with pockets for receiving rolling elements is guided.

The main advantage of this storage is that undesired lateral migration of the cage is reliably prevented by accommodating it in the circumferential gap. Due to the design of the cage according to the invention, high dynamic and static load ratings are achieved compared to conventional cage bearings, since almost the same number of rolling elements can be accommodated even in the case of full-length bearings. Another advantage lies in the fact that the bearing can be assembled in a simple manner due to the two-part design of the outer ring.

In a development of the invention it is apparent from claim 2 that the race half are provided on their outer surface with uniformly spaced recesses. These recesses in the jacket area act as air cushions and ensure that a temperature barrier is formed 3 is, so that the heat transfer from the outside radially inwards in the direction

Center of the rolling bearing is prevented.

According to claim 3, the sheet metal part in the area of the sealing ring should engage around the sealing areas on the end face with a radially inward-pointing leg, so that a sealing bead molded onto the outer radial end of the reinforcement ring is squeezed between the latter and one of the outer raceway halves when the leg rolls on. This elastic tensioning of the sealing bead ensures a particularly effective sealing of the rolling bearing.

According to a further feature of the invention according to claim 4 it is provided that the two race halves of the outer bearing ring are manufactured as separate components or can be produced by blasting an output ring.

Finally, according to the second independent claim 5, reversing the design, the inner bearing ring can also consist of two race halves spaced apart in the axial direction, so that a circumferential gap is formed in which a freely rotatable disc cage with pockets for receiving rolling elements is guided.

The invention is explained in more detail using the following exemplary embodiment.

Brief description of the drawings

Show it:

FIG. 1 shows a flywheel consisting of two flywheels in a semi-longitudinal section,

FIG. 2 shows a detail of FIG. 1 on an enlarged scale, 4

Figures 3 u. 4 shows a side view or a longitudinal section through a race half and

Figure 5 is a side view of a disc cage.

Detailed description of the drawings

FIG. 1 shows a dual-mass flywheel combined with a friction clutch, which is used to transmit the torque from an internal combustion engine to a downstream transmission of a motor vehicle. The dual mass flywheel consists of a first flywheel mass 1, which is fixed on the crankshaft of an internal combustion engine. A second flywheel mass 2 can be rotated relative to the first flywheel mass 1 to a limited extent. The second flywheel mass 2 is supported relative to the first flywheel mass 1 via a ball bearing 3. In the present case, the second flywheel mass 2 is designed as a lining carrier against which a clutch disc 5 of a friction clutch 4 can be braced via a pressure plate. A cover 7 of the friction clutch 4 is rotatably connected to the second flywheel 2. It has radially protruding and circumferentially distributed lugs 8, which serve as the first support base for compression springs 6, which are supported with their other end in pockets of the first flywheel 1. The clutch disc 5 is provided with a hub 9, which is used for the rotationally fixed connection to a transmission input of the motor vehicle.

The mounting of the two centrifugal masses 1 and 2 using the single-row ball bearing 3 is described in more detail with reference to FIG 2. The two flywheels 1 and 2 each have an axial end section 10 and 11, between which the single-row ball bearing 3 is arranged. As can also be seen from FIG. 2, a sheet metal molded part 13 is arranged between the lateral surface of the receiving bore of the axial end section 11 of the flywheel mass 2 and an outer bearing ring 12 and engages around the outer bearing ring 12 with an annular region 14 over its entire axial extent. This annular region 14 of the sheet metal part 13 goes on its the flywheel 1 5 opposite end into a radially inward region 15, which covers the outer bearing ring 12 on its end face. This area 15 is adjoined by an area 16 extending in the axial direction, which in turn is followed by an area 17 pointing radially inward. This merges into an axial region 18 pointing in the direction of the center of the bearing 3, which is adjoined by a radially extending region 19, which in turn is detached from an axially extending region 20. An inner ring 21 of the ball bearing 3 is encompassed on its end face by the region 19 and on its outer surface by the region 20 of the sheet metal molded part 13. In this way, a lubricant storage space 22 is formed which, filled with lubricant, ensures a long service life of the rolling bearing 3.

The other side of the ball bearing 3 is closed by a sealing ring, which consists of a reinforcement ring 23 with molded sealing areas. The sealing areas are formed, on the one hand, by a sealing bead 24, which is arranged at the radially outer end of the reinforcing ring 23, and, on the other hand, by sealing lips 25, which are arranged at the radially inner end of the reinforcing ring 23 and abut the inner circumferential surface of the inner ring 21. The sealing bead 24 is squeezed by a radial leg 26 of the sheet metal part 13 between the latter and the bearing outer ring 12 or the race half 27, so that a good seal of the ball bearing 3 is ensured.

The outer bearing ring 12 is composed of the two raceway halves 27 and 28, which are spaced apart from one another in the axial direction, so that a circumferential gap 29 is formed, in which a disk cage 30 shown in a side view in FIG. 5 is freely rotatable. This disc cage 30 has pockets 32, which are separated from one another by webs 31 and serve to receive the bearing balls 33. The thinner the webs 31 in the circumferential direction, the more bearing balls 33 can be accommodated in the disc cage 30 and the higher its load-bearing capacity. By guiding the disc cage 30 in the circumferential gap 29, its axial displaceability is made impossible. 6

It can further be seen from FIGS. 2, 3 and 4 that the two race halves 27, 28 of the outer bearing ring 12 are provided with recesses 34 which are uniformly spaced apart on their outer surface. These recesses act as air cushions and ensure that the heat transfer due to friction is reduced from the outside in the direction of the ball bearing 3.

LIST OF REFERENCE NUMBERS

1 first flywheel 18 axial area

2 second flywheel 19 radial area

3 ball bearings 20 axial area

4 Friction clutch 21 inner ring

5 clutch disc 22 lubricant reservoir 6 compression spring 23 reinforcement ring

7 cover 24 sealing bead

8 Approach 25 sealing lip

9 hub 26 legs

10 axial end section 27 race half 1 1 axial end section 28 race half

12 outer bearing ring 29 gap

13 sheet metal part 30 disc cage

14 annular area 31 web

15 radial area 32 pocket 16 axial area 33 bearing ball

1 7 radial region 34 recess

Claims

8 patent claims

1. Flywheel, in particular for internal combustion engines, with two relatively small rotatable flywheels (1, 2), between which a roller bearing (3) is arranged, the outer bearing ring (12) in a cylindrical bore of the second flywheel (2) and the inner one Bearing ring (21) is arranged on a cylindrical collar of the first flywheel mass (1), with a sheet metal part (13) being arranged between the outer bearing ring (12) and the second flywheel mass (13), with the rolling bearing (3) on one end face encloses an axially outward shaping, so that a cavity (22) is formed, while the rolling bearing (3) is sealed on its other end face by means of a sealing ring consisting of a reinforcing ring (23) and molded sealing areas (24, 25), thereby characterized in that the outer bearing ring (12) consists of two race halves (27, 28) spaced apart from one another in the axial direction, so that a circumferential gap (29) is formed in which a freely rotatable disc cage (30) with pockets (32) for receiving rolling elements (33) is guided.

2. Flywheel according to claim 1, characterized in that the race halves (27, 28) are provided on their outer surface with uniformly spaced recesses (34).

3. Flywheel according to claim 1, wherein the sheet metal part (13) in the area of the sealing ring surrounds the sealing areas with a radially inward-pointing leg (26) on the end face, characterized in that a sealing bead (24) molded onto the outer radial end of the reinforcing ring (23) ) is crushed between the leg and the race half (27) when the leg (26) rolls on. 9

4. Flywheel according to claim 1, characterized in that the race halves (27, 28) of the outer bearing ring (12) are made as separate sheet metal components or are produced by blasting an output ring.

5. Flywheel according to the preamble of claim 1, characterized in that the inner bearing ring (21) consists of two spaced apart in the axial direction race halves (27, 28) so that a circumferential gap (29) is formed, in which a free rotatable disc cage (30) with pockets (32) for receiving rolling elements (33) is guided.