VIBRATION ABSORBER BUSH AND INNER TUBE ABSORBER HAVING SUCH A VIBRATION ABSORBER BUSH

Abstract

A vibration absorber bush for an inner tube absorber for absorbing torsional and flexural vibrations, for the coaxial assembly in a hollow shaft which is penetrated by a central longitudinal axis includes at least one largely cylindrical first elastic element and a largely cylindrical second elastic element which are in each case disposed to be coaxial with the longitudinal axis and to be mutually adjacent in the radial direction. In embodiments, a reinforcement element is disposed between the elastic elements.

Claims

1. A vibration absorber bush for an inner tube absorber for absorbing torsional and flexural vibrations, for coaxial assembly in a hollow shaft which is penetrated by a central longitudinal axis, comprising: at least one largely cylindrical first elastic element and a largely cylindrical second elastic element which are in each case disposed to be coaxial with the longitudinal axis and to be mutually adjacent in the radial direction, and including a reinforcement element disposed between the first and second elastic elements.

2. The vibration absorber bush according to claim 1, wherein the reinforcement element is held exclusively by the first and second elastic elements.

3. The vibration absorber bush according to claim 1, wherein the reinforcement element is held exclusively by the first and second elastic elements and is surrounded by the first and second elastic elements.

4. The vibration absorber bush according to claim 1, wherein said vibration absorber bush comprises an outer bearing sleeve disposed on an external circumference of the first elastic element that is the outermost in terms of the radial direction.

5. The vibration absorber bush according to claim 1, wherein said vibration absorber bush comprises an inner bearing sleeve disposed on an internal circumference of the second elastic element that is the innermost in terms of the radial direction.

6. The vibration absorber bush according to claim 1, wherein said vibration absorber bush comprises an outer bearing sleeve disposed on an external circumference of the first elastic element that is the outermost in terms of the radial direction; and said vibration absorber bush comprises an inner bearing sleeve disposed on an internal circumference of the second elastic element that is the innermost in terms of the radial direction.

7. The vibration absorber bush according to claim 1, wherein the first and second elastic elements are configured such that the first elastic element has a shorter longitudinal extent in comparison to the second elastic element that is directly adjacent and is more centrally disposed in terms of the radial direction.

8. The vibration absorber bush according to claim 1, wherein at least one of the first elastic element and the second elastic element has at least one longitudinal cut-out.

9. The absorber bush according to claim 1, wherein the first elastic element and the second elastic element each have a longitudinal cut-out, and the longitudinal cut-outs of adjacent first and second elastic elements are disposed to be mutually offset in the circumferential direction.

10. An inner tube absorber for a coaxial assembly in a hollow shaft, said inner tube absorber in the longitudinal direction thereof being penetrated by a central longitudinal axis, comprising at least one vibration absorber bush according to claim 1 and including an absorber mass.

11. The inner tube absorber according to claim 10, wherein the at least one vibration absorber bush and/or the absorber mass is configured and/or disposed such that a ratio between the bending frequency to be absorbed and the torsion frequency to be absorbed is in the range between 10:9 and 10:1.

12. The inner tube absorber according to claim 10, wherein the at least one vibration absorber bush and/or the absorber mass is configured and/or disposed such that a ratio between the bending frequency to be absorbed and the torsion frequency to be absorbed is in the range between 10:7 and 10:3.

13. The inner tube absorber according to claim 10, wherein the at least one vibration absorber bush and/or the absorber mass is configured and/or disposed such that a ratio between the bending frequency to be absorbed and the torsion frequency to be absorbed is more than 10:5.

14. The inner tube absorber according to claim 10, wherein the at least one vibration absorber bush and/or the absorber mass is configured and/or disposed such that the ratio between the overall length of the inner tube absorber along the longitudinal axis and the bush external diameter is at least 2.5.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Further features, details, and advantages of embodiments disclosed herein are derived from the wording of the claims as well as from the description hereunder of exemplary embodiments by means of the drawings in which:

[0058] FIG. 1 shows a lateral view of an inner tube absorber according to a first embodiment;

[0059] FIG. 2 shows a cross-sectional view along the line II-II in FIG. 1;

[0060] FIG. 3 shows an oblique view of the inner tube absorber according to FIG. 1;

[0061] FIG. 4 shows a lateral view of an inner tube absorber according to a second embodiment;

[0062] FIG. 5 shows a cross-sectional view along the line V-V in FIG. 4;

[0063] FIG. 6 shows an oblique view of the inner tube absorber according to FIG. 4;

[0064] FIG. 7 shows a lateral view of an inner tube absorber according to a third embodiment;

[0065] FIG. 8 shows a cross-sectional view along the line VIII-VIII in FIG. 7;

[0066] FIG. 9 shows an oblique view of the inner tube absorber according to FIG. 7;

[0067] FIG. 10 shows a lateral view of an inner tube absorber according to a fourth embodiment;

[0068] FIG. 11 shows a cross-sectional view along the line XI-XI in FIG. 10;

[0069] FIG. 12 shows an oblique view of the inner tube absorber according to FIG. 10;

[0070] FIG. 13 shows a lateral view of an inner tube absorber according to a fifth embodiment;

[0071] FIG. 14 shows a cross-sectional view along the line XIV-XIV in FIG. 13;

[0072] FIG. 15 shows an oblique view of the inner tube absorber according to FIG. 13;

[0073] FIG. 16 shows an assembly view of an inner tube absorber having a solid-body absorber mass; and

[0074] FIG. 17 shows an assembly view of an inner tube absorber having a hollow-body absorber mass.

[0075] The same or mutually equivalent elements are in each case identified by the same or similar reference signs in the figures and, unless expedient, are therefore not repeatedly described. The disclosures contained in the entire description can be applied in an analogous manner to identical parts with the same reference signs or the same component descriptions, respectively. Also, the positional indications chosen in the description, such as for example top, bottom, lateral, etc., relate to the figure which is directly described and illustrated and in the case of a change in the position are to be a applied in analogous manner to the new position. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent inventive solutions or solutions according to embodiments disclosed herein.

[0076] Five exemplary embodiments of inner tube absorbers 12a, 12b, 12c, 12d, and 12e are in each case shown by way of three figures in an assembled position (installed position) in FIGS. 1 to 15. The inner tube absorbers 12a, 12b, 12c, 12d, and 12e differ in each case in terms of various details which are to be explained with reference to the respective figures. The vibration absorber bushes shown in an exemplary embodiment are of identical configuration. Unless technically precluded, individual features of embodiments are to be considered as conjointly disclosed and capable of being combined with one another. Features which have already been described once are not to be described once again in order to avoid repetitions, even when said features are also illustrated in other figures. While inner tube absorbers having two bushes are shown in the figures, the features described therein are however also intended to be disclosed and claimed so as to apply to inner tube absorbers having only one bush.

DETAILED DESCRIPTION

[0077] FIG. 1 shows an inner tube absorber 12a according to a first embodiment, said inner tube absorber 12a being configured so as to be substantially rotationally symmetrical to a longitudinal axis L. An absorber mass 24a is disposed in a radially inward manner. The absorber mass 24a has a rotationally symmetrical cylindrical basic shape having end sides 42, said cylindrical basic shape being free of any unbalance in terms of a rotating movement about the longitudinal axis L. The absorber mass 24a can also be surrounded by an external sleeve which is likewise preferably free of any unbalance and has a hollow cylindrical basic shape and a casing from an elastomer.

[0078] The inner tube absorber 12a serves for the coaxial assembly in a hollow shaft 14 which in FIG. 16 is shown in an exemplary manner in the context of an assembly view. The inner tube absorber 12a comprises the absorber mass 24a which is configured as a solid-body absorber mass, and two vibration absorber bushes 10a of identical configuration. Each vibration absorber bush 10a in one of the two distal end regions is connected, preferably press-fitted, to the absorber mass 24a.

[0079] Each of the two vibration absorber bushes 10a on the circumference has a casing 52 of elastomer. The vibration absorber bushes 10a have a sufficient stiffness such that the inner tube absorber 12a can be permanently fastened in a hollow shaft by way of a press-fit. The casing 52 has studs 54 which are disposed on the circumference and protrude radially outwards from the external circumferential face of the casing 52, and by means of which a production tolerance of the internal diameter of the hollow shaft 14 can be compensated for. The studs 54 are disposed so as to be uniformly spaced apart from one another in the circumferential direction and are distributed across the entire external circumferential face of the casing 52. The studs 54 have an elongate main body which extends parallel to the longitudinal axis L. The studs 54 are compressed when being press-fitted into the hollow shaft 14. A compression face 66 is identified for press-fitting and contacting an assembly tool. Said compression face 66 can be that location of the vibration absorber bush 10a that is the most exposed in the longitudinal direction. The bush 10a at the end facing the absorber mass 24a has an impact face 68 by way of which said bush 10a during the assembly can impact the absorber mass 24a in order for compressive forces to be introduced or for compressive forces to be received.

[0080] As is shown in FIG. 2, each of the two vibration absorber bushes 10a is likewise centrally penetrated by the longitudinal axis L, and comprises a cylindrical first elastic element 16a having a main body which has a radial thickness RDa, and a cylindrical second elastic element 16b having a main body which has a radial thickness RDb. RDa and RDb are presently of identical size. The elastic elements 16a, 16b are in each case aligned so as to be coaxial with the longitudinal axis L and are disposed so as to be mutually adjacent in the radial direction R. The main bodies of the elastic elements 16a, 16b in the axial direction terminate in each case so as to be level with the reinforcement element 18. The two elastic elements 16a, 16b therefore have dissimilar diameters, wherein the respective outer first elastic element 16a encompasses the inner second elastic element 16b. A reinforcement element 18 in the form of a cylindrical reinforcement sleeve is disposed between the two elastic elements 16a, 16b in such a manner that said reinforcement element 18 mutually separates the adjacent elastic elements 16a, 16b.

[0081] FIG. 3 shows in particular that the reinforcement element 18 is held exclusively by the elastic elements 16a, 16b and in the radial direction R is surrounded by the elastic elements 16a, 16b. The reinforcement element 18 on both axial sides thereof can be provided with a covering 56 which can also cover the two elastic elements 16a, 16b, this however not leading to the elastic elements 16a, 16b being connected as opposed to the concept of embodiments disclosed herein. Despite the covering 56, the reinforcement element 18 in functional terms specifically separates the elastic elements 16a, 16b, or the main bodies thereof, from one another. The covering 56 does not transmit any noteworthy elongation, compression, and torsion between adjacent elastic elements 16a, 16b. A covering 56 can also result from the reinforcement element 18 being placed into a mould and subsequently being overmoulded with an elastic material, preferably an elastomer, at least in portions in order for the elastic elements 16a, 16b to be configured. The elastic elements 16a, 16b then remain functionally separated. The covering can also cover at least in portions bearing sleeves 20a, 20b.

[0082] The vibration absorber bushes 10a also comprise an outer bearing sleeve 20a which is disposed on the external circumference of the outermost elastic element 16a, as well as an inner bearing sleeve 20b which is disposed on the inner circumference of the innermost elastic element 16b. The bearing sleeves are configured so as to be cylindrical. The outer bearing sleeve 20a supports the casing 52 including the studs 54 and serves as a support in relation to an internal circumferential face 58 of the hollow tube 14.

[0083] Each of the two elastic elements 16a, 16b has four uniformly spaced-apart longitudinal cut-outs 22a, 22b which are mutually aligned in the radial direction R, or are disposed so as to be mutually offset by an angle of 0° in relation to the longitudinal axis L—an extreme spread of stiffness is present within the elastic elements 16a, 16b. In terms of the image plane of FIG. 2, the elastic elements 16a, 16b are specifically extremely hard in the horizontal and vertical direction (by virtue of the material present) and are extremely soft in a region which is tilted by 45° in relation thereto (by virtue of the aligned longitudinal cut-outs 22a, 22b). The outer longitudinal cut-outs 22a occupy a larger segment than the longitudinal cut-outs 22b, on account of which the inner longitudinal cut-outs 22b are completely covered by the outer longitudinal cut-outs 22a. An overall spread of the stiffness can be achieved across 360° (in terms of the cross section) on account of this alignment of the longitudinal cut-outs 22a, 22b. The elastic elements 16a, 16b are moreover configured in such a manner that the first elastic element 16a has a shorter longitudinal extent in comparison to the directly adjacent second elastic element 16b which is disposed so as to be more central in terms of the radial direction R. The two elastic elements 16a, 16b are however mutually centred in the longitudinal direction.

[0084] The connection between the vibration absorber bushes 10a and the absorber mass 24a is now to be described by means of FIG. 3. The absorber mass 24a along the longitudinal axis L has adjacent portions 26a, 26b, 26c of dissimilar diameters. On account thereof, a spacer shoulder 28a which in the longitudinal direction has a spacing from the outer bearing sleeve 20a is configured between the portions 26a and 26b. A detent shoulder 28b on which the inner bearing sleeve 20b impacts, or on which the latter bears, is thus configured between the portions 26a and 26b. There is also a spacing between the detent shoulder 28b and the reinforcement element 18. The external diameter of the portion 26c in relation to the internal diameter of the inner bearing sleeve 20b is dimensioned such that a permanent press-fit can be implemented between these two elements. The vibration absorber bushes 10a are thus press-fitted to the absorber mass 24a. On account of the vibration absorber bush 10a been present on both distal ends of the absorber mass 24a, the absorber mass 24a is fixed in the longitudinal direction L, in the radial direction R, and in the circumferential direction. The outer bearing sleeve 20a proximal to the absorber mass is lengthened and at least partially covers the portion 26c, wherein a radial spacing is present therebetween. It is envisioned that the ratio between the overall length of the inner tube absorber 12a, or the absorber length 60, respectively, along the longitudinal axis L and the bush external diameter 48 is at least 2.5. The cardanic resonance frequency can be increased, for example, by two vibration absorber bushes having a maximum radial stiffness and a maximum axial spacing.

[0085] It is advantageous for the bush 10a and/or the absorber mass 24a to be configured and/or disposed in such a manner that a radial space between the circumferential portion of the absorber mass 24a (here the portion 26b) and the outer bearing sleeve 20a has a radial length that is smaller than a radial space between the circumference 46 of the absorber mass 24a and the internal circumferential face 58 of the hollow shaft 14 (or the external circumferential face of the bearing sleeve 20a, optionally minus the length which is created on account of the compression when assembling). On account thereof, the outer bearing sleeve 20a which is preferably encompassed by an elastomer serves as a radial deflection delimitation for the absorber mass 24a. If the absorber mass were to specifically deflect in the radial direction, said absorber mass only impacts the outer bearing sleeve 20a and not the internal circumferential face 58 of the hollow shaft 14. This prevents unintentional noises and significantly increases the service life of the absorber mass and the hollow shaft.

[0086] A second embodiment of an inner tube absorber 12b is to be described hereunder with reference to FIGS. 4 to 6, wherein only the points of differentiation in comparison the first embodiment are to be substantially discussed here.

[0087] The inner tube absorber 12b is penetrated by the longitudinal axis L and comprises an absorber mass 24a and two vibration absorber bushes 10b which are disposed at both ends of the absorber mass 24b. The elastic elements 16a and 16b furthermore have in each case four longitudinal cut-outs 22a, 22b, but the inner, or second, longitudinal cut-outs 22b in relation to the outer, or first, longitudinal cut-outs 22a are disposed so as to be offset at an angle of 45° in terms of the longitudinal axis L—there is an extreme equality of stiffness within the elastic elements 16a, 16b.

[0088] In terms of the image plane of FIG. 5, the elastic elements 16a, 16b are specifically set to the same hardness in the horizontal direction, in the vertical direction, and in a direction which is tilted by 45° in relation thereto (by virtue of the material present and by virtue of the longitudinal cut-outs 22a, 22b which in relation to the longitudinal axis are distributed across the circumference). An overall stiffness uniformity across 360° (in terms of the cross section) can be implemented on account of this mutual radial offset of the longitudinal cut-outs 22a, 22b.

[0089] The absorber mass 24b along the longitudinal axis L has adjacent portions 26a, 26b, 26c of dissimilar diameters, wherein the diameter of the portion 26a is enlarged in comparison to the first embodiment. The outer bearing sleeve 20a by way of the impact face 68 thereof herein can be pushed onto the likewise enlarged spacer shoulder 28a during the assembly, and a compressive force can thus also be introduced into the circumferential region of the absorber mass 24b, or be received from there.

[0090] The outer bearing sleeve 20a moreover serves as a radial deflection delimitation for the absorber mass 24a, specifically in that said outer bearing sleeve 20a at least in portions covers the absorber mass 24b in the longitudinal direction. Moreover, in the radial direction between the outer bearing sleeve 20a (or optionally the surrounding material) and the absorber mass 24b (here the portion 26b), there is a smaller radial spacing than in the radial direction between the absorber mass 24b (here the portion 26a, since the latter has the largest diameter) and the internal diameter of the hollow shaft 14. Alternatively, the radial spacing from the circumferential face of the bush 10b in the installed state can also serve as a reference.

[0091] A third embodiment of an inner tube absorber 12c is to be described hereunder with reference to FIGS. 7 to 9, wherein only the points of differentiation in comparison to the first embodiment are to be substantially discussed here.

[0092] The inner tube absorber 12c is penetrated by the longitudinal axis L and comprises an absorber mass 24c and two vibration absorber bushes 10c which are disposed at both ends of the absorber mass 24c. Two delimitation rings 44 which for fixing the absorber mass 24c bear circumferentially on the absorber mass 24c are disposed on the mass circumference 46 of the absorber mass 24c. The delimitation rings 44 in the axial direction terminate at the end side 42 of the absorber mass 24c.

[0093] Each vibration absorber bush 10c henceforth no longer comprises any outer bearing sleeve 26a. On account thereof, the first elastic element 16a forms a circumferential external region and therefore also comprises the studs 54 in the same manner as described above. A press-fit with the hollow shaft 14 therefore may require sufficient friction between the studs 54 and the internal circumferential face 58.

[0094] FIG. 9 shows that the absorber mass 24c is configured as a hollow-body absorber mass which has a longitudinally continuous central recess 50. On account of the absorber mass 24c being hollow at least in the distal end regions thereof, the vibration absorber bush is no longer press-fitted onto a portion of the absorber mass but press-fitted into said absorber mass. To this end, the vibration absorber bush 10c has an inner bearing sleeve 20b having a absorber-mass-proximal extension portion 20c which engages in the central recess 50 so as to establish a press-fit with the vibration absorber bush 10c. A support portion 62 which is embodied so as to be cylindrical and can be formed from the material of the elastic element 16b is provided between the inner bearing sleeve 20b and the second elastic element 16b. The support portion 62 in the axial direction at the end proximal to the absorber mass terminates at the inner bearing sleeve 20b and proximal to the absorber mass bears on the end face 42. On account thereof, the vibration absorber bush 10c is supported in relation to the absorber mass 24c. An axial spacing is present between the end face 42, on the one hand, and the two elastic elements 16a, 16b as well as the reinforcement element 18, on the other hand.

[0095] The vibration absorber bushes 10c have in each case three uniformly spaced-apart assembly recesses 40 which penetrate the vibration absorber bushes 10c in the longitudinal direction. As will yet be described with reference to FIG. 17, these assembly recesses 40 serve for the penetration by an assembly tool 30b and, on account thereof, the direct introduction of a compressive F into the absorber mass 24c.

[0096] A fourth embodiment of an inner tube absorber 12d is to be described hereunder with reference to FIGS. 10 to 12, wherein only the points of differentiation in comparison to the first embodiment are to be substantially discussed here.

[0097] The tube absorber 12d is penetrated by the longitudinal axis L and comprises an absorber mass 24d and two vibration absorber bushes 10d which are disposed at both ends of the absorber mass 24d. The absorber mass 24d is configured as a hollow-body absorber mass, and the vibration absorber bush 10d has the outer bearing sleeve 20a which supports the casing 52, however without studs 54 and thus without any elastic or elastomeric press-fit within the hollow shaft 14.

[0098] A fifth embodiment of an inner tube absorber 12e is to be described hereunder with reference to FIGS. 13 to 15, wherein only the points of differentiation in comparison to the first embodiment are to be substantially discussed here.

[0099] The inner tube absorber 12e is penetrated by the longitudinal axis L and comprises an absorber mass 24e and two vibration absorber bushes 10e which are disposed at both ends of the absorber mass 24e.

[0100] Each vibration absorber bush 10e no longer comprises any outer bearing sleeve 26a and also no inner bearing sleeve 26b. On account thereof, the first elastic element 16a forms a circumferential external region and therefore also comprises the studs 54 in the same manner as described above. Since the vibration absorber bushes 10e now no longer comprise any inner bearing sleeve 20b, the absorber mass 24e has an extension portion 64. The respective vibration absorber bush 10e is disposed by way of a press-fit on this extension portion 64.

[0101] An assembly of the inner tube absorber 12a is shown in FIG. 16, wherein such an assembly takes place in the same or a similar manner for each inner tube absorber 12a, 12b which has an absorber mass 24a, 24b which has a sufficiently large axial face which can be directly contacted by an assembly tool. This in most instances applies to solid-body absorber masses. The inner tube absorber 12a comprises already-described vibration absorber bushes 10a wherein the latter for improved clarity hereinafter are to be referred to as the vibration absorber bush 10a1 (indented vibration absorber bush) and the vibration absorber bush 10a2 (indenting vibration absorber bush).

[0102] An assembly tool 30a for assembling the inner tube absorber 12a in a coaxial manner in a hollow shaft 14 is used for this assembly. The assembly tool 30a comprises a cylindrical main body 32a having a circular bush contact face 34a for contacting the vibration absorber bush 10a2, as well as a mass contact face 34b which for contacting the absorber mass 24a is offset in the longitudinal direction in relation to the bush contact face 34a. The vibration absorber bush 10a2, proximal to the assembly tool, before and after the assembly protrudes by the dimension LA1 (first longitudinal spacing) from the end side 42 of the absorber mass 24a. A spacing dimension LA2 (second longitudinal spacing) is present before and after the assembly on the opposite side between the vibration absorber bush 10a2 in the region of the outer bearing sleeve 20a, or the impact face 68, respectively, and the spacer shoulder 28a. The mass contact face 34b in the direction of the inner tube absorber 10a2 is now offset by the sum of these two dimensions LA1 and LA2 in relation to the bush contact face 34a, referred to as LA3 (third longitudinal spacing), where: LA1+LA2=LA3. Prior to the assembly, there thus exists a direct correlation between the dimensions of the bush/the absorber and the tool.

[0103] More specifically, the main body 32a has a base portion 36a and a protrusion portion 36b of a smaller diameter which projects in relation to the base portion 36a, wherein the base portion 36a comprises the bush contact face 34a, and the protrusion portion 36b comprises the mass contact face 34b.

[0104] The assembly method for the inner tube absorber 12a shown now provides that first the hollow shaft 14, the inner tube absorber 12a, and the assembly tool 30a are provided. The assembly tool 30a, the inner tube absorber 12a, and the hollow shaft 14 are thereafter aligned so as to be mutually coaxial, as is shown in FIG. 16. An axial compressive force F is then applied by means of the assembly tool 30a. On account thereof, the mass contact face 34b comes into contact with the absorber mass 24a, while the second longitudinal spacing LA2 is present between the facing (facing the assembly tool) vibration absorber bush 10a2, or the compression face 66 thereof, respectively, and the bush contact face 34a, and applying the compressive force F leads to an axial spacing between the compression face 66 and the bush contact face 34a being shortened, and the second longitudinal spacing LA2 between the facing vibration absorber bush 10a2, or the impact face 68, respectively, and the absorber mass 24a, or the shoulder 28a, respectively, being lengthened by the same measure until the bush contact face 34a comes into contact with the compression face 66 of the facing vibration absorber bush 10a2.

[0105] Thereafter, the facing vibration absorber bush 10a2 as well as the absorber mass 24a can be likewise axially displaced, this leading to the second longitudinal spacing LA2 at the indented vibration absorber bush 10a1 being reduced to zero, and the absorber mass 24a impacting the impact face 68 of the indented vibration absorber bush 10al, and thus also displacing the vibration absorber bush 10al. On account thereof, the inner tube absorber 12a is pushed into the hollow shaft 14 up to a predefined position (not shown) within the hollow shaft 14.

[0106] The assembly tool 30a is retracted upon reaching this position, on account of which no compressive force F is applied any longer, on account of which the elasticity of the vibration absorber bushes 10a1 and 10a2 leads to the absorber mass 24a being centred so as to be centric between the vibration absorber bushes 10a1 and 10a2. Likewise, the first longitudinal spacings LA1 and the second longitudinal spacings LA2 reassume their dimensions prior to the assembly.

[0107] An assembly of the inner tube absorber 12c is shown in FIG. 17, wherein such an assembly takes place in the same or a similar manner for each inner tube absorber 12c, 12d, 12e which has an absorber mass 24c, 24d, 24e which on the end side of the absorber does not have a sufficiently large axial face which can be directly contacted by an assembly tool. This applies in most instances to absorber masses which are hollow at least in distal end regions. The inner tube absorber 12c comprises two already-described vibration absorber bushes 10c, wherein the latter for improved clarity hereinafter are to be referred to as the vibration absorber bush 10c1 (indented vibration absorber bush) and the vibration absorber bush 10c2 (indenting vibration absorber bush).

[0108] An assembly tool 30b for assembling the inner tube absorber 12c so as to be coaxial in a hollow shaft 14 is used for this assembly. The assembly tool 30b comprises a cylindrical main body 32b having a circular bush contact face 34a for contacting the vibration absorber bush 10c2 on a compression face 66, as well as the mass contact face 34b which for contacting the absorber mass 24c is offset in the longitudinal direction in relation to the bush contact face 34a. The vibration absorber bush 10c2, proximal to the assembly tool, before and after the assembly protrudes by the dimension LA1 (first longitudinal spacing) from the end side 42 of the absorber mass 24a. A spacing dimension LA2 (second longitudinal spacing) is present on the side of the vibration absorber bush 10c2 that is opposite the assembly tool 30b, between the vibration absorber bush 10c2 in the region of the outer bearing sleeve 20a and the spacer shoulder 28a. The end side 42 can also configure the spacer shoulder 28a. The mass contact face 34b in the direction of the inner tube absorber 10c2 is now offset by the sum of these two dimensions LA1 and LA2 in relation to the bush contact face 34a, referred to as LA3 (third longitudinal spacing), where: LA1+LA2=LA3. Prior to the assembly, there thus exists a direct correlation between the dimensions of the bush/the absorber and the tool.

[0109] More specifically, the main body 32b has a base portion 38a and at least one pressure pin 38b which is connected to the base portion 38a and extends in the longitudinal direction, and which pressure pin 38b is suitable for penetrating through a corresponding assembly recess 40 in the vibration absorber bush 10c2 and for contacting the absorber mass 24c, preferably on the end side 42 thereof. The base portion 38a comprises the bush contact face 34a, and the at least one pressure pin 38b comprises the mass contact face 34b. The at least one pressure pin 38b can have a greater longitudinal extent than the vibration absorber bush 10c1/10c2. The dimension of this larger longitudinal extent of the pressure pin 38b likewise has the spacing dimension LA2 (second longitudinal spacing).

[0110] The assembly method for the inner tube absorber 12c shown now provides that first the hollow shaft 14, the inner tube absorber 12c, and the assembly tool 30b are provided. The assembly tool 30b, the inner tube absorber 12c, and the hollow shaft 14 are thereafter aligned so as to be mutually coaxial, as is shown in FIG. 17. The pressure pins 38b penetrate the assembly recesses 40. An axial compressive force F is then applied by means of the assembly tool 30b. On account thereof, the mass contact face 34b comes into contact with the absorber mass 24c, while the second longitudinal spacing LA2 is present between the facing (facing the assembly tool) vibration absorber bush 10c2, or the compression face 66 thereof, respectively, and the bush contact face 34a, and applying the compressive force F leads to an axial spacing between the compression face 66 and the bush contact face 34a being shortened, and the second longitudinal spacing LA2 between the facing vibration absorber bush 10c2 and the absorber mass 24c being lengthened by the same measure until the bush contact face 34a comes into contact with the compression face 66 of the facing vibration absorber bush 10c2.

[0111] Thereafter, the facing vibration absorber bush 10c2 as well as the absorber mass 24c can be likewise axially displaced, this leading to the second longitudinal spacing LA2 at the vibration absorber bush 10c1 being reduced to zero and the absorber mass 24c impacting an impact face 68 of the vibration absorber bush 10c1 and thus also displacing the vibration absorber bush 10c1. On account thereof, the inner tube absorber 12c is pushed into the hollow shaft 14 up to a predefined position (not shown) within the hollow shaft 14.

[0112] The assembly tool 30b is retracted upon reaching this position, on account of which no compressive force F is any longer applied, on account of which the elasticity of the vibration absorber bushes 10c1 and 10c2 leads to the absorber mass 24c being centred so as to be centric between the vibration absorber bushes 10c1 and 10c2. Likewise, the second longitudinal spacings LA2 reassume their dimensions prior to the assembly.

[0113] The disclosure is not limited to any of the afore-described embodiments but can be modified in many ways. All of the features and advantages, including constructive details, spatial arrangements, and method steps, that are derived from the claims, the description, and the drawing can be relevant to the disclosure individually as well as in the most varied combinations.

[0114] All combinations of at least two features disclosed in the description, the claims and/or the figures are included in the scope of the invention as defined by the claims.

[0115] In order to avoid repetitions, features which have been disclosed in the context of the device are to be considered disclosed and claimed in the context of the method. Likewise, features disclosed in the context of the method are to be considered disclosed and claimed in the context of the device.