EP1694976A1

EP1694976A1 - Rotating joint for the mutual connection of two shaft ends in particular in the drivetrain of a motor vehicle

Info

Publication number: EP1694976A1
Application number: EP04803761A
Authority: EP
Inventors: Joachim Rothe; Josef Bauer
Original assignee: SGF Sueddeutsche Gelenkscheibenfabrik GmbH and Co KG
Current assignee: SGF Sueddeutsche Gelenkscheibenfabrik GmbH and Co KG
Priority date: 2003-12-17
Filing date: 2004-12-10
Publication date: 2006-08-30
Also published as: WO2005059391A1; DE10359281B3; AU2004298531A1; JP2007514904A; CN1890480A; KR20060126512A; US20070080534A1

Abstract

The invention relates to a joint doughnut (10), made from a rubbery elastic material, with a central axis (A), at least two first and two second connection bodies (32, 34), each for fixing to a shaft end, arranged alternately with the axes thereof (B) parallel to the central axis (A) and around the above at angular separations from each other. Flexible inserts (20) are embedded in the joint doughnut (10) which extend around adjacent connection bodies (32, 34). A centering device (40) is provided for the mutual centering of both shaft ends, comprising a first and a second front plate (22, 24) which can be connected to either front face (12, 14) of the joint doughnut (10), centered relative to each other, such as to pivot about the joint centre (C), lying on the central axis (A). Independent of the subsequent fixing thereof to the first or second shaft end, the first connection body (32) is fixed to the first front plate (22) and the second connection body (34) is fixed to the second front plate (24) in a rigid and non-rotating manner.

Description

Swivel coupling for mutually connecting two shaft ends, in particular in the drive train of a motor vehicle

The invention relates to a swivel coupling according to the preamble of claim 1.

Swivel couplings of this type are known from DE 2 255 533 AI and from DE 3 942 432 Cl. According to DE 2 255 533 AI, a support body in the form of a three-pointed star is arranged centrally to the pitch circle of the joint disc within the joint disc. Flexible inserts in the form of loop packages are supported on the spikes of the star-shaped support body. The support body has a central hole which is intended to receive a centering pin which is fastened to one of the two shaft ends which are connected to one another by the joint disk. A centering that meets today's requirements cannot be achieved with this support, since a given shape of the loop packages can only be maintained with limited accuracy for manufacturing reasons and is subject to changes in operation, which include depend on the transmitted torque. There is also a risk that the flexible inserts will be damaged by the teeth of the star-shaped support body over time.

As a standard solution for the mutual centering of two shaft ends connected by a generic articulated coupling, a complete separation between the articulated disc and the centering has become established, as is known for example from DE 3 942 432 Cl. There, the joint disc only has the task of transmitting torques and, to a certain extent, axial forces and has an inner space enclosed by it in a ring, in which a separate centering device is arranged. This consists of a cup-shaped end area formed on one of the two shaft ends, a centering bush pressed into it with vulcanized-in lining, which leaves a central hole free, and a centering pin formed on the other shaft end, which engages in this hole. However, this arrangement requires an installation space for the assembly of the swivel coupling that is at least twice as wide in the axial direction as the joint disk so that the centering pin can be inserted into the centering bush. From DE 2 130 247 B2, however, rotary joint couplings are also known in which a connection between two shaft ends, which transmits torques and axial forces and at the same time is centering, is made of a rubber-like joint disk is made of elastic material, which is partially enclosed by a pot-shaped metal body, and in which further metal parts are embedded in such a way that two groups of three threaded bolts each as connecting bodies for connection to a flange on the two associated shaft ends are prevented from moving under the Effect of torques, centrifugal forces and other external forces to be significantly removed from a given pitch circle. The pot-shaped metal body has an end plate formed by three arms arranged in a star shape, which abuts an end face of the joint disk and has three holes lying on the pitch circle, through which one of the three threaded bolts of the first group extends, which with the flange on one of the two Are screwed. These three threaded bolts each extend through a metal insert embedded in the joint disk, which is supported from the inside on a cylindrical wall of the pot-shaped metal body which encloses the joint disk. The three threaded bolts of the second group, which are connected to a flange of the other shaft end, each extend through a recess in a star-shaped metal insert which is also embedded in the joint disk, and this is supported on a central collar which is formed on the cup-shaped metal body and in engages a central recess of the joint disc. The usability of this centering integrated in the joint disk depends on the fact that the embedded metal parts are kept precisely positioned in relation to one another when the joint disk is vulcanized, which is complex. The use of such metal parts is, moreover, incompatible with the flexible inserts, which are typical of a type of swivel coupling of the type mentioned at the outset and are to be further developed by the invention, embedded in the flexible disc and which extend in the manner of thread loops around adjacent connecting bodies.

The invention is based on the object of designing a swivel coupling of the type mentioned in such a way that it can be produced in a simple manner, requires little installation space for its assembly, particularly in the axial direction, and high demands on the accuracy of the centering of the two interconnected Shaft ends met.

The object is achieved with the features of claim 1.

The fact that, according to the invention, two end plates arranged on one end face of the joint disk are provided, that these end plates are centered in an articulated manner with respect to one another, and that all connection bodies, be it bushings or Threaded bolts, each rigidly attached to one of the two end plates, all connection bodies, and thus also the associated shaft ends, remain centered in relation to one another in all operating states of the joint coupling according to the invention. Because the attachment of each of the connection bodies to the end plate assigned to it is also non-rotatable from the outset, the risk existing in known swivel couplings of the type mentioned at the outset is ruled out that when the swivel coupling is assembled with the shaft ends to be connected by it, undesired voltage differences in the flexible inserts are created, which could change the operating characteristics of the flexible joint and reduce its service life.

Advantageous developments of the invention result from the subclaims.

Exemplary embodiments with further details of the invention are described below with the aid of schematic drawings. In the drawings are

Fig. L is an end view of a first swivel coupling according to the invention and

Fig. 2 shows the section II-II in Fig. 1;

Fig. 3 is an end view of a second swivel coupling according to the invention and

Fig. 4 the section IV-IV in Fig. 3; Fig. 5 is an end view of a third swivel coupling according to the invention and

Fig. 6 the section VI-VI in Fig. 5;

Fig. 7 is an end view of a fourth swivel coupling according to the invention and

Fig. 8 section VIII-VIII in Fig. 7;

Fig. 9 is an end view of a fifth swivel coupling according to the invention and

10 shows the section X-X in FIG. 9.

The swivel coupling shown in FIGS. 1 and 2 has, as an essential torque-transmitting component, an articulated disk 10, which essentially consists of rubber or other rubber-like elastic material, is designed to be essentially rotationally symmetrical with respect to a central axis A, by means of two essentially flat, axially normal end faces , namely a first end face 12 and a second end face 14 is limited and has a circular central recess 16. Six circular cylindrical sleeves 18 are vulcanized into the joint disk 10, the axes B of which are arranged parallel to the central axis A on a common pitch circle at uniform angular intervals of 60 degrees. Each of the sleeves 18, together with each of the sleeves 18 adjacent to them, is in the form of flexible inserts 20 looped around by thread loops, which are also vulcanized into the material of the joint disk 10. To this extent, the joint disk 10 is of a conventional type.

The articulated disk 10 is arranged between two end plates stamped from sheet steel, namely a first end plate 22 and a second end plate 24, each of which has three radially projecting arms 26 and 28, starting from a flat central region. The arms 26 and 28 are cranked toward the articulated disk 10 and rest on the end faces 12 and 14 thereof. All arms 26 and 28 each have a circular hole 30, and these holes are in any case when the swivel coupling is assembled, as shown, on a common pitch circle 31 with the sleeves 18. The holes 30 in the arms 26 of the first Face plate 22 is aligned with every second sleeve 18, and second face plate 24 is rotated by 60 degrees with respect to first face plate 22, so that holes 30 in their arms 28 are aligned with one of the three remaining sleeves 18.

A first connection body 32 is inserted into each of the three holes 30 of the first end plate 22 and into the sleeves 18 aligned with these holes, preferably with a press fit. In a corresponding manner, a second connection body 34 is inserted into the three holes 30 of the second end plate 24 and into the sleeves 18 aligned therewith, preferably pressed in with a press fit. As a result, the two end plates 22 and 24 are held together with the joint disk 10. In addition, the two end plates 22 and 24 each have a cylindrical central collar 36 and 38, which protrudes into the central recess 16 of the joint plate 10 according to FIG. 2 without directly touching it. The two collars 36 and 38 are components of a centering device 40, which keeps the two end plates 22 and 24 centered in relation to one another and connects them to one another pivotably about an articulation center C lying on the central axis A.

2, the first collar 36 formed on the first end plate 22 has a significantly smaller diameter than the second collar 38 formed on the second end plate 24. The two collars 36 and 38 thus delimit an annular space in which, according to FIG Joint body 42 with a convex spherical outer surface and cylindrical inner surface and an outer joint body 44 with a concave spherical inner surface and cylindrical outer surface are arranged such that the two spherical surfaces lie against one another. The inner joint body 42 is pushed with its cylindrical inner surface onto the first collar 36, preferably pressed on with a press fit; the outer joint body 44 is embedded, preferably vulcanized, with its cylindrical outer surface into the second collar 38 via an intermediate layer 46 made of rubber or another elastomer.

The arrangement described so far is additionally stabilized in that each of the connection bodies 32 and 34 is rigidly attached to the end plate 22 and 24 assigned to it. In the case of the swivel coupling shown in FIGS. 1 and 2, this rigid fastening is produced in that each of the connecting bodies 32 and 34 has a flange 48 which bears against the associated arm 26 or 28 of the relevant end plate 22 or 24 and is welded to the relevant arm. Preferably, a plurality of welding points 49 offset from one another at approximately the same angular spacings around the relevant axis B are provided on each flange 48.

The pitch circle 31 of the holes in the arms 26 and 28 of the end plates 22 and 24, which is common in the assembled state of the swivel coupling, has a diameter D with which the pitch circle diameter of the sleeves 18 - or, more generally, holes - in the joint disk 18 do not coincide from the start needs. It may be advantageous if the joint disk 10 as such has a pitch circle diameter that is larger than D. In this case, it is necessary to radially compress the joint disk 10, for example with a tensioning strap that wraps around its outer circumferential surface, before the connection bodies 32 and 34, which are already in their end plates 22 and 24 and are preferably welded to them, into the joint disk 18 be pressed in. The radial compression results in a preload in the joint disk 10, which has a desired influence on the torque-twist angle characteristic curve of the joint disk in certain applications. One speaks of a "soft zero crossing" when changing the drive train equipped with a pre-tensioned flexible disk 10 from pull to push operation. The characteristic curve of the articulated disk 10 remains essentially unchanged over its entire service life, even if the articulated disk is removed in each case for repairs on the drive train. The end plates 22 and 24, in conjunction with the connecting bodies 32 and 34, ensure that the radial prestress in the joint disk 10 is retained.

3 and 4 differs from that shown in FIGS. 1 and 2 in that each of the connection bodies 32 and 34 has a cylindrical extension 50 which projects beyond the associated flange 48 and which is for this purpose is provided to engage with a tight fit in a bore of a flange or the like on the associated shaft end, not shown. The required precisely fitting connection to each of the two shaft ends to be connected to one another by the swivel coupling can also be established by using fitting screws for fastening the connection body 32 on one of the two shaft ends and the connection body 34 on the other shaft end. This applies in the same way to the embodiments according to FIGS. 1 and 2, according to FIGS. 3 and 4, according to FIGS. 5 and 6 and according to FIGS. 9 and 10, where the connecting bodies 32 and 34 are cylindrical bushes, respectively.

3 and 4 from the one shown in FIGS. 1 and 2 lies in the design of the centering device 40, in which, according to FIG. 4, the central collar 38 formed on the second end plate 44 has a smaller diameter and from the collar 36 formed on the first end plate 22 is enclosed in a ring. Arranged in the annular space between these two collars 36 and 38 are an inner joint body 52 which is pushed onto the collar 38 and is preferably pressed on with an interference fit with a hint of a T-shaped bead profile, an elastomer body 54 surrounding this profile and a bearing sleeve 56 pressed into the first collar 36 , The elastomer body 54 is preferably a rubber body which is vulcanized onto the outside of the inner joint body 52 and onto the inside of the bearing sleeve 56. 4, insofar as comparable to the first collar 36 in FIG. 2, has a closed end and is thereby stiffened. 4, the centering device 40 is largely protected against the ingress of dirt; in addition to the design of the end plates 22 and 24, a cap 58, which is pressed into the first collar 36, contributes to this.

5 and 6 differs from that shown in FIGS. 3 and 4 in that the connecting bodies 32 and 34 are formed by flangeless pipe sections that directly with the associated arm 26 and 28 of the first end plate 22 and second end plate 24 are welded. 6, the second collar 38 formed on the second end plate 24 is dimensioned considerably shorter, and its fixed connection to the inner joint body 52 is produced by a centering pin 59 pressed into this and into the collar 38. The rotary joint according to FIGS. 7 and 8 corresponds to that shown in FIGS. 3 and 4 with the exception that the connecting bodies 32 and 34 are not tubular but are designed as solid bolts and each have a threaded pin 60 which projects beyond their cylindrical shoulder and which is intended for this purpose is to extend through a flange of the associated first or second shaft end and to be fastened to the rear thereof with a nut. A further special feature of the embodiment shown in FIGS. 7 and 8 is that each of the connection bodies 32 and 34 has an annular groove 61 at a distance from its flange 48 corresponding to the sheet thickness of the associated arm 26 or 28, into which an end region the associated sleeve 18 engages. This engagement is caused by the fact that the sleeve 18 was originally somewhat longer and protruded beyond the relevant end face 12 or 14 of the joint disk 10 and when the connecting body 32 or 34 is pressed in through the associated hole 30 into the relevant sleeve 18 has bent radially inwards.

9 and 10 corresponds to that shown in FIGS. 1 and 2 with the exception that the centering device 40 is not accommodated in the central recess 16 of the joint disk 10 but is arranged radially outside the joint disk 10. In this case too, however, the centering device 40 includes a first collar 62 formed on the first end plate 22 at a radial distance from the lateral surface of the joint disk 10 and a second collar 64 formed on the second end plate 24, which together define an annular space. This annular space contains, vulcanized to the first collar 62 by an intermediate layer 66 made of rubber or another elastomer, an annular inner joint body 68 with a convex spherical outer surface and an annular outer joint body 70 with a concave spherical inner surface which is also pressed into the second collar 64 abuts directly on the convex spherical outer surface of the inner joint body 68. In this configuration of the centering device 40, too, its center of articulation C lies on the central axis A in the middle between the two end faces 12 and 14 of the articulated disk 10.

Another difference of the swivel coupling according to FIGS. 9 and 10 compared to the swivel couplings shown in the previous figures is that the rigid attachment of the connecting bodies 32 and 34 to the associated end plate 22 and 24 is not produced by welding, but rather by the fact that a area adjacent to the flange 48 of the relevant connector body from its outer surface with an anchoring profile 72, for example a notch tooth profile is provided, which is pressed into the hole 30 of the associated end plate 22 or 24 in such a way that the connection bodies are secured against rotation and preferably also axially immovable to the relevant end plate.

Claims

claims

1. swivel coupling for mutually connecting two shaft ends, in particular in the drive train of a motor vehicle, with

- a joint disc (10) made of rubber-like elastic material, which has a central axis (A),

- At least two first and two second connection bodies (32, 34), which alternate with one another, with their own axis (B) parallel to the central axis (A), around this, at angular intervals from one another in the joint disk (10) and intended for this purpose are to be attached to one of the shaft ends,

- flexible inserts (20), which are embedded in the joint disc (10) and extend around adjacent connecting bodies (32, 34), and - a centering device (40) for centering the two shaft ends, characterized in that

- The centering device (40) has a first and a second end plate (22, 24), which are arranged on each end side (12, 14) of the joint disc (10) centered in relation to each other and around a lying on the central axis (A) Joint center (C) are pivotable, and

- Irrespective of their later attachment to the first or second shaft end, the first connection body (32) on the first end plate (22), and the second connection body (34) on the second end plate (24) are rigidly and non-rotatably fastened.

2. Swivel joint according to claim 1, characterized in that the two end plates (22, 24) each have a collar (36, 38) engaging in the joint disk (10) and are centered in relation to one another via these collars.

3. Swivel coupling according to claim 1, characterized in that the two end plates (22, 24) each have a collar (62, 64) which surrounds the joint disc (10) radially on the outside and are centered with respect to one another via these collars.

4. Swivel joint according to claim 2 or 3, characterized in that the two end plates (22, 24) via their collars (36,

38; 62, 64) are held axially against the joint disc (10).

5. Swivel joint according to one of claims 1 to 4, characterized in that the connection body (32, 34) at the edge of a hole receiving it (30) of the associated end plate (22, 24) are welded to it.

6. A swivel coupling according to one of claims 1 to 5, characterized in that the connecting bodies (32, 34) are anchored in a rotationally fixed manner by an anchoring profile (72) formed on them on the associated end plate (22, 24).

7. A swivel coupling according to one of claims 1 to 6, characterized in that the connecting bodies (32, 34) each in a sleeve (18) belonging to the joint disk (10), embedded therein and wrapped by at least one of the flexible inserts (20). are used.

8. Swivel joint according to claim 7, characterized in that the sleeve (18) with the associated connection body (32, 34) in the direction of its axis (B) transmitting tensile forces and thereby the associated end plate (22, 24) on the joint plate ( 10) is kept tight.

9. swivel coupling according to one of claims 1 to 8, characterized in that the connecting body (32, 34) each have a flange (48) for attachment to the associated end plate (22, 24).

10. Swivel coupling according to one of claims 1 to 9, characterized in that the connecting bodies (32, 34) each have a shoulder (50) for centering on the associated shaft end.

11. Swivel joint according to one of claims 1 to 10, characterized in that the joint disk (10) is held by the end plates (22, 24) in connection with the connecting bodies (32, 34) under radial prestress.