DE4116841A1 - Homo-kinetic linkage for vehicle rear axle - which has flange assembly incorporating rubber elements in annular gap - Google Patents

Abstract

The homokinetic linkage for a vehicle rear axle has the linkage supporting the linkage shaft connected to a flange attached to the drive bevel gear. The flange (16, 16a, 16b) comprises a first (20, 20a, 20b) and a second (21, 21a, 21b) flange part. The first flange part is directed towards the bevel gear (12) and the second part to the homokinetic linkage (24) and the shaft (19). Both flange parts are joined to each other with the interposition of one or more rubber connecting elements (23) in the annular gap (22). ADVANTAGE - Vehicle axle linkage having good insulation and hence quiet running properties, with a high degree of bending and flexibility.

Description

The invention relates to an articulated connection between Drive bevel gear and propeller shaft of motor vehicle driven Rear axles by means of a homokinetic joint, whereby the the universal joint receiving the universal joint shaft on one with the drive bevel gear rotatably and axially immovable connected flange is attached.

The use of a homokinetic joint to connect Drive bevel gear and propeller shaft has the advantage that comparative wise large flexion angles and sliding paths between the two Shaft parts can be realized, which is also common with the practiced use of articulated discs (instead of homokinetic joints) is not possible. Homokinetic Joints ensure a vibration-free start of the Vehicle, even under difficult driving conditions (e.g. An drive on a mountain route with high payload). The one in use Disadvantages of joint disks - large longitudinal loading movements of the subframe combined with severe deformations of the center bearing of the relevant PTO drive shaft - are avoided by using homokinetic joints.

It is also known for attaching the homokinetic Joint on the (driven) rear axle of motor vehicles to use a simple steel flange. In practice it has but shown that rear axles designed in this way  unpleasant noise (so-called rear axle howl).

The object of the invention is to drive primarily bene rear axles of motor vehicles suitable articulation create bond, which the advantages of a flexible disc (good insulation and therefore smooth running of the drive train) with those of a homokinetic joint (large flexion angles of 10 ° and large sliding paths of over 10 mm) combined, but the inadequacies inherent in the individual concepts (see above).

According to the invention, the task with an articulated joint solution of the type described in the introduction by the Flange consisting of a first flange part and a second flange part exists, the first flange part of the drive bevel gear and the second flange part the constant velocity joint and so that the propeller shaft is assigned, and that the two Flange parts with the interposition of one or more ver binding elements made of an elastic material with each other are connected.

DE-OS 37 09 768 is an angularly movable shaft clutch with a clutch bell arranged on one shaft end, the other end of the shaft axially at a radial distance overlaps at least partially, became known, the gap formed in this way by a radially inside and outside bridged fixed kinokinetic joint is. Here the homokinetic joint lies on the side of the patient a support sleeve made of metallic material, and the support sleeve and the clutch bell are through at least one Damping layer made of rubber connected relatively movable. It but this is a front axle drive in which the problems underlying the present application (Deformation of the central bearing of the cardan shaft) does not occur. In contrast to the prior art known from DE-OS 37 09 768 Technology is the joint connection according to the invention while driving stool attached. It acts on the axle differential and  not - as with DE-OS 37 09 768 - on the drive axle shafts.

In the present invention, this becomes known as such homokinetic joint attached to a special flange that takes over the function of the joint disk known as such. As a result, the construction effort (compared to a conceivable pure Addition of a known homokinetic joint with a known joint disc) significantly reduced. Come anyway the advantages of the two known articulations (see above) fully to bear, and at the same time their inadequacies opportunities (see above) avoided.

After a functional and in terms of small construction expenditure and space very advantageous embodiment of the Invention is proposed that the flange one with the homokinetic joint connected inner ring as a second flange part and one concentrically with a radial distance around Closing outer ring as the first flange part, the attacks the drive bevel gear, and that in this way he giving the annular gap between the inner ring and outer ring intermediate layer connecting both flange parts from one elastic material is arranged. Due to the approximately circular / cylindrical elastic intermediate layer becomes a safe and permanent power transmission guaranteed.

The inner ring and outer ring of the flange are expedient approximately pot-shaped, and the homokinetic joint is screwed to the bottom of the inner ring. This conception he possible "nesting" of the two flange parts and of the homokinetic joint, which is a very space-saving con structure of the entire joint means.

In a further advantageous embodiment of the invention, the Outer ring an internal toothing and the inner ring an outer ver have teeth, the teeth of the external teeth in um catch direction between two adjacent teeth of the Internal teeth should be arranged. Preferably here for the outer diameter of the external toothing on the second flange  partly smaller than the outer diameter of the internal toothing on first flange part.

Such a gear system does not only guarantee one safe power transmission, but also prevents - even with a long service life and a high-strength bean stress - tearing off the elastic intermediate layer the connection points.

According to another possible embodiment of the invention the first flange part has several at a uniform angle spaced axial bores and the second Flange part several assigned to the axial bores and in these concentrically engaging cylindrical extensions, and the annular spaces between the cylindrical Extensions and the inner walls of the axial bores are included filled in elastic material. In the sense of a space-saving Conception of the joint as a whole is in advanced training standing thought suggested that the cylindrical fort sets of continuous threaded holes for screwing the have the second flange part with the constant velocity joint.

Finally, a third possible variant of the invention sees before that the second flange part is substantially disc-shaped is formed and of edge segments of the first flange part over most of its circumference with a radial distance above is gripped and that between the overlapped sections of the disc-shaped second flange part and the overlapping Edge segments of the first flange part essentially one annular layer of elastic material is arranged. This embodiment opens up particularly advantageous possibilities transmission of strong torques.

An advantageous embodiment of the above embodiment shape is characterized in that on the outer circumference of the second Flange part several radial at regular angular intervals mutually arranged extensions are arranged between grasp two adjacent edge segments of the first flange part, such that between each extension and the surrounding areas  a U-shaped space is created in the first flange part, and that the U-shaped spaces with elastic material are filled out. Preferably the is essentially ring shaped layer of elastic material with the U-shaped Material layers connected in one piece.

Now what type, shape and Shore hardness of the practical Ver Realization of the invention used elastic As far as materials are concerned, it will be appropriate to use these parameters based on tests to optimize for each individual case They depend on various factors, in particular special of the speed, torque and weight of the vehicle. In any case, the use as an elastic material a suitable rubber mixture can be recommended.

The invention is now based on exemplary embodiments in the Illustrated drawing, which are described below. It shows:

Fig. 1 - in longitudinal section - an execution form of a universal joint shaft connection to a motor vehicle rear axle,

Fig. 2 position to the connecting flange of Fig. 2 in Separatdar,

Fig. 3 the flange viewed in FIG. 2 in "X" direction,

Fig. 4 shows another embodiment of a flange for connecting the drive shaft and pinion gear for a motor vehicle rear axle, in Schnittdar position corresponding to Fig. 2,

Fig. 5 shows the subject of FIG. 4, in view corresponding to Fig. 3,

Fig. 6 shows a further variant of a flange to Verbin extension of drive shaft and pinion gear for a motor vehicle rear axle, in view corresponding to Fig. 3 and 5 (viewing direction "X" in Fig. 7),

Fig. 7 is a section along the line VII-VII in Fig. 6,

Fig. 8 is a section along the line VIII-VIII in Fig. 6, and

Fig. 9, the object of Fig. 7, viewed in plan view (arrow direction "Y").

In FIG. 1, 10 denotes a rear axle of a motor vehicle designed as a drive axle. It can be a common rear axle construction, so that a complete representation and description of the concerned rear axle is unnecessary. Within a numbered with the axle housing 11, a drive bevel gear 12 is supported by a tapered roller bearing. 13 The drive shaft 12 is provided with a spline 14 on which a corresponding internal toothing 15 , generally designated 16, is arranged in a rotationally fixed manner. At its free end the drive bevel gear 12 has a thread 17 onto which a nut 18 which fixes the flange 16 in the axial direction is screwed.

The flange 16 - in cooperation with further parts, which will be explained in more detail below - has the function of connecting the drive bevel gear 12 in a rotationally fixed manner to an articulated shaft, generally designated 19 , which leads to the respective driven wheel (not shown) of the vehicle in question.

As can be seen in particular Figs. 2 and 3, is formed for this purpose the flange 16 in two parts. It consists of a pinion gear 12 to the associated first flange portion 20 and one of the hinge shaft 19 associated second flange 21st Fig. 2 and 3 also make it clear that the second flange part 21 is formed as an inner ring, which was concentrically enclosed by the first flange part 20 designed as an outer ring with radial Ab. Both flange parts 20 and 21 are, as shown in particular in FIG. 2, approximately cup-shaped. In a resulting between the two flange portions 20 and 21 an annular gap 22, the two flange parts 20, 21 connecting the intermediate layer 23 made of an elastic material, preferably rubber, arranged.

The connection of the second flange part 21 to the cardan shaft 19 takes place via a total joint number of 24 , which is a constant velocity joint. Such homokinetic joints are known in their structure and function, so that a more detailed explanation of the joint 24 is unnecessary in the present case. The homokinetic joint 24 has on its circumference a plurality of bores 25 , preferably arranged at uniform angular intervals, each of which is penetrated by a fastening screw 26 . The holes 25 in the constant velocity joint 24 are threaded holes 27 in the second flange part 21 . The fastening screws 26 have at their free end a threaded pin 28 , by means of which they are screwed into the threaded holes 27 of the second flange part 21 . In this way, a rotationally fixed and axially immovable fixation of the constant velocity joint 24 and thus the drive shaft 19 relative to the second flange part 21 is ensured.

From the apparent from Fig. 1 and described in the above described construction, it follows that the torque from the articulated shaft 19 to the drive bevel gear 12 must be transmitted from the annular elastic intermediate layer 23 arranged between the two flange parts 20 , 21 . This important function is optimized by recognizable special measures from FIG. 3. For this purpose, the outer ring of the first flange part 20 has an internal toothing 29 , and a corresponding external toothing 30 is formed on the inner ring of the second flange part 21 . Here, the teeth of the external toothing 30 each project centrally between two adjacent teeth of the internal toothing 29 (see FIG. 3). At the same time, the teeth 29 , 30 are dimensioned such that the outer diameter D _{A of} the outer toothing 30 on the second flange part 21 is smaller than the outer diameter D _{I of} the inner toothing 29 on the first flange part 20 . In this way, a sufficient thickness of the annular rubber intermediate layer 23 remains guaranteed.

In the embodiment according to FIGS. 4 and 5, the flange is designated overall by 16 a. The two individual flange parts have the reference numerals 20 a and 21 a. The special feature of this embodiment is that the first flange part 20 a has a plurality of axial bores 31 which are arranged at uniform angular distances from one another and which are assigned to the second flange part 21 a a plurality of cylindrical projections 32 which engage concentrically in the axial bores 31 . This results in annular gaps between the cylindrical extensions 32 and the inner walls of the axial bores 31 , which are filled with elastic material 33 , preferably rubber. The cylindrical extensions 32 have continuous threaded holes 34 which for screwing the second flange part 21 a and thus the entire flange 16 a with a constant velocity joint, for. B. the type shown in Fig. 1, serve.

In the embodiment according to FIGS . 6-9, the flange is denoted overall by 16 b. According to the rest of the above-described embodiments according to FIGS. 1-3 and according to FIGS. 4 and 5, a first flange part with 20 b and a second flange part with 21 b is numbered. In particular Fig. 8 shows, the second flange portion 21 b substantially slices shaped. On the major part of its circumference, it is overlapped by edge segments 35 of the first flange part 20 b at a radial distance (see in particular FIG. 6). Between the overlapped sections of the disk-shaped second flange part 21 b and the overlapping edge segments 35 of the first flange part 20 b, an essentially annular layer 36 made of elastic material, preferably rubber, is arranged. This is, however, as shown in Fig. 6 can be seen, not continuous in the circumferential direction, but is interrupted by radial projections 37 which integrally b formed on the second flange portion 21 and each other at equal angular intervals are arranged. The projections 37 engage between two adjacent edge segments 35 of the first flange part 20 b (see in particular FIG. 6). As is evident from FIGS . 6 and 9 in particular, this results in a U-shaped space 38 between each extension 37 and the surrounding parts of the first flange part 20 b, which is filled with elastic material 39 , preferably rubber. Fig. 6 also makes it clear that the substantially annular layer 36 made of elastic material is integrally connected to the U-shaped elastic material layers 39 . In this way, the transmission of high torques between the two flange parts 20 b and 21 b is ensured with sufficient elasticity between these two parts.

To attach a constant velocity joint to the flange part 21 b are - similar to the embodiments according to FIGS. 1-3 or 4 and 5 - several mutually spaced threaded holes provided in the embodiment of FIGS. 6-9 are numbered at 40 .

Claims (11)

1. Articulated connection between the drive bevel gear and propeller shaft of driven motor vehicle rear axles by means of a homokinetic joint, wherein the homokinetic joint receiving the propeller shaft is attached to a bevel gear rotatably and axially immovably connected flange, characterized in that the flange ( 16 , 16 a , 16 b) consists of a first flange part ( 20 , 20 a, 20 b) and a second flange part ( 21 , 21 a, 21 b), the first flange part of the drive bevel gear ( 12 ) and the second flange part of the constant velocity joint ( 24 ) and thus the joint shaft ( 19 ) is assigned, and that the two flange parts ( 20 , 20 a, 20 b; 21 , 21 a, 21 b) with the interposition of one or more connecting elements ( 23 , 33 , 36 , 39 ) are connected together from an elastic material. 2. Articulated connection according to claim 1, characterized in that the flange ( 16 ) has an inner ring ( 21 ) connected to the constant velocity joint ( 24 ) as the second flange part and an outer ring ( 20 ) concentrically enclosing it with a radial distance as the first flange part which engages the drive shaft ( 12 ), and that an intermediate layer ( 23 ) made of an elastic material connecting the two flange parts ( 20 , 21 ) is arranged in an annular gap ( 22 ) between the inner ring ( 21 ) and the outer ring ( 20 ). Fig. 1-3). 3. Hinge connection according to claim 2, characterized in that the inner ring ( 21 ) and outer ring ( 20 ) of the flange ( 16 ) are approximately pot-shaped and that the constant velocity joint ( 24 ) is screwed to the bottom of the inner ring ( 21 ) (26- 28). 4. Articulated connection according to claim 2 or 3, characterized in that the outer ring ( 20 ) has an internal toothing ( 29 ) and the inner ring ( 21 ) has an external toothing ( 30 ) and that the teeth of the external toothing ( 30 ) in the circumferential direction in each case between two adjacent teeth of the internal toothing ( 29 ) are arranged. 5. Hinge connection according to claim 4, characterized in that the outer diameter (D _A ) of the outer toothing ( 30 ) on the second flange part ( 21 ) is smaller than the outer diameter (D _I ) of the inner toothing ( 29 ) on the first flange part ( 20 ). 6. Articulated connection according to claim 1, characterized in that the first flange part ( 20 a) several at regular angular intervals arranged axial bores ( 31 ) and the second flange part ( 21 a) several the axial bores ( 31 ) associated and concentrically engaging in this cylindrical Extensions ( 32 ) and that the annular spaces between the cylindrical extensions ( 32 ) and the walls of the axial bores ( 31 ) are filled with elastic material ( 33 ) ( Fig. 4 and 5). 7. Hinge connection according to claim 6, characterized in that the cylindrical extensions ( 32 ) have continuous threaded bores ( 34 ) for screwing the second flange part ( 21 a) to the constant velocity joint ( 24 ). 8. Articulated connection according to claim 1, characterized in that the second flange part ( 21 b) is substantially disc-shaped and of edge segments ( 35 ) of the first flange part ( 20 b) on the overwhelming part of its circumference with a radial distance over and that Between the overlapped sections of the disk-shaped second flange part ( 21 b) and the overlapping edge segments ( 35 ) of the first flange part ( 20 b) an essentially annular layer ( 36 ) made of elastic material is arranged ( Fig. 6-9). 9. Articulated connection according to claim 8, characterized in that on the outer circumference of the second flange part ( 21 b) a plurality of radial, spaced apart from each other extensions ( 37 ) are formed, each between two adjacent edge segments ( 35 ) of the first flange part ( 20 b) engage in such a way that between each extension ( 37 ) and the surrounding parts ( 35 ) of the first flange part ( 20 b) a U-shaped space ( 38 ) is created, and that the U-shaped spaces ( 38 ) with elastic material ( 39 ) are filled out. 10. Hinge connection according to claim 8 and 9, characterized in that the substantially annular layer ( 36 ) made of elastic material with the U-shaped elastic material layers ( 39 ) is integrally connected. 11. Articulated connection according to one or more of the preceding claims, characterized in that a rubber mixture is used as the elastic material ( 23 , 33 , 36 , 39 ).