Balancing device

Abstract

A balancing device for turbochargers comprises a base body having a centrally disposed receiver. A rotation element to be balanced can be axially inserted to hold the rotation element in the receiver such as to turn about its axis of rotation. A number of hydraulic cylinders are arranged around the central receiver on the base body for fixing a core assembly of the turbocharger in the central receiver. The base body is in the form of a decoupling plate having an inner plate section and a stationarily positioned outer plate section elastically connected to the inner plate section and surrounding the inner plate section. The decoupling plate has a number of peripheral slots resiliently decoupling the inner plate section from the outer plate section such that a number of separate holding sections are formed on the de-coupling plate.

Claims

1. A balancing device for turbochargers, comprising a base body which has a centrally disposed receiver wherein a rotation element to be balanced can be axially inserted in order to hold the rotation element in the receiver such as to turn about its axis of rotation; and a number of hydraulic cylinders arranged around the central receiver being provided on the base body, by means of which hydraulic cylinders the rotation element can be fixed in the central receiver, wherein the base body is in the form of a decoupling plate which has an inner plate section and a stationarily positioned outer plate section elastically connected to the inner plate section and surrounding the inner plate section, the decoupling plate having a number of peripheral slots by means of which the inner plate section is resiliently decoupled from the outer plate section such that a number of separate holding sections are formed on the decoupling plate.

2. The balancing device according to claim 1, wherein the peripheral slots each extend over a length of at least 70% of the entire length of each holding section of the decoupling plate.

3. The balancing device according to claim 2, wherein in the end regions of the peripheral slots (12) recesses, spring bars or spring tabs are at least partially provided in the decoupling plate.

4. The balancing device according to claim 2, wherein the peripheral slots are formed spaced from one another and overlap at least partially in their end regions so as to form the holding sections.

5. The balancing device according to claim 2, wherein an even number of holding sections are provided which are arranged and formed mirror symmetrically to a longitudinal center plane of the decoupling plate.

6. The balancing device according to claim 1, wherein in the end regions of the peripheral slots recesses, spring bars (14) or spring tabs (15) are at least partially provided in the decoupling plate (9).

7. The balancing device according to claim 6, wherein at least two adjacent peripheral slots are directly separated from one another by respectively radially running recesses.

8. The balancing device according to claim 7, wherein an even number of holding sections are provided which are arranged and formed mirror symmetrically to a longitudinal center plane of the decoupling plate.

9. The balancing device according to claim 6, wherein the peripheral slots are formed spaced from one another and overlap at least partially in their end regions so as to form the holding sections.

10. The balancing device according to claim 6, wherein an even number of holding sections are provided which are arranged and formed mirror symmetrically to a longitudinal center plane of the decoupling plate.

11. The balancing device according to claim 1, wherein the peripheral slots are formed spaced apart from one another and overlap at least partially in their end regions so as to form the holding sections.

12. The balancing device according to claim 11, wherein an even number of holding sections are provided which are arranged and formed mirror symmetrically to a longitudinal center plane of the decoupling plate.

13. The balancing device according to claim 1, wherein an even number of holding sections are provided which are arranged and formed mirror symmetrically to a longitudinal center plane of the decoupling plate.

14. The balancing device according to claim 1, wherein a total of three holding sections are provided on the decoupling plate which each extend over an angular range of at least 70 along the circumference of the base body (6).

15. The balancing device according to claim 1, wherein the peripheral slots or the recesses are made in the base body by means of water jet cutting and/or by means of wire-electro discharge machining.

16. The balancing device according to claim 1, wherein the rotation element is braced in the central receiver of the base body by substantially axial displacement of the hydraulic cylinders.

17. The balancing device according to claim 1, wherein the hydraulic cylinders are arranged on or fastened to the inner plate section.

18. The balancing device according to claim 1, wherein the hydraulic cylinders can be moved within the inner plate section axially parallel to the axis of rotation of the rotation element such that the lever elements adjoining the hydraulic cylinders are displaced such that a force-fit and/or form-fit connection between the lever elements and the core assembly is established.

19. The balancing device according to claim 1, wherein a number of pneumatic cylinders are provided on the outer fixed plate section in order to position the hydraulic cylinders and/or the lever elements on the core assembly.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The drawings show as follows:

(2) FIG. 1 a top view of a decoupling plate according to the invention;

(3) FIG. 2 a decoupling plate according to the invention with an inserted core assembly, from the side;

(4) FIG. 3 a sectional illustration of the decoupling plate along section line AA according to FIG. 1; and

(5) FIG. 4 a partial illustration of the coupling plate according to the invention with the core assembly inserted according to rectangle B in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

(6) FIG. 1 shows a balancing device 1 for a core assembly 2 of a turbocharger. The core assembly 2 comprises a shaft 3 to each of the ends of which a turbine wheel 4 and a compressor wheel 5 of the turbocharger are fastened and fixed in place by means of a shaft nut 3a.

(7) The balancing device 1 is provided with a base body 6 which has a centrally positioned receiver 7 in order to insert the core assembly 2 into the receiver 7 and to keep the rotation element 3, 4, 5 turning about its axis of rotation by means of bearings (not detailed). Provided on the base body 6 are a number of hydraulic cylinders 8 arranged around the receiver 7, by means of which the core assembly 2 is fastened in the central receiver 7.

(8) The base body 6 has a circular decoupling plate 9 which comprises an inner plate section 10 and an outer plate section 11 disposed stationarily in the balancing device 1, elastically connected to the inner plate section 10 and surrounding the inner plate section 10.

(9) In the decoupling plate 9, arranged along the circumference of the de-coupling plate 9, i.e. along an arc of a circle around the central axis of rotation of the rotation element 3, 4, 5, peripheral slots 12 are provided by means of which the inner plate section 10 is resiliently decoupled from the outer plate section 11.

(10) The peripheral slots 12 are arranged here so that they extend almost along the entire circumference of the decoupling plate 9. The individual peripheral slots 12 are spaced apart from one another so that four separate holding sections 13 are formed in the decoupling plate 9. For this purpose, the peripheral slots 12 are respectively arranged over a length of 80 of the circumferential length of each holding section 13 of the decoupling plate 9.

(11) In the end regions of the peripheral slots 12 recesses in the form of spring bars 14 and spring tabs 15 are provided in the decoupling plate 9, which recesses are formed adapted to the anticipated loading in the holding sections 13, i.e. in the region of anticipated bending and torsion forces as spring tabs 15, in the region of anticipated linear forces caused by upwards and downwards movements as spring bars 14.

(12) As can be seen more precisely in FIG. 1, the end regions of the peripheral slots 12 in the 12 o'clock position and in the 6 o'clock position are spring tabs 15 which are arranged so that, spaced apart from one another, they overlap in the region of the formation of the tab form and are appropriate for compressing vibrations due to rotations.

(13) However, in the 3 o'clock and in the 9 o'clock position the end regions of two adjacent peripheral slots 12 are in the form of spring bars 14 which extend spaced apart from one another parallel to the axis centre point of the decoupling plate 9.

(14) In order to fix the core assembly 2 to the decoupling plate 9, four holding sections 13 provide an even number thereof which are arranged mirror symmetrically to a longitudinal centre plane of the decoupling plate 9.

(15) In an exemplary embodiment which is not shown, only three holding sections are provided on the decoupling plate 9 which each extend over an angular range of 100 along the circumference of the base body 6. However, this embodiment will not be discussed any further in this exemplary embodiment.

(16) In the present exemplary embodiment, the peripheral slots 12 and the recesses 14, 15 are made in the decoupling plate 9 by means of water jet cutting. Accordingly, the decoupling mat 9 is, furthermore, made in one part. By means of the various embodiments of the peripheral slots 12 and the recesses 14, 15 and the bars 14a, 15a formed between them, resilient mounting of the inner plate section 10 by the fixed outer plate section 11 with equalisation of force effects is achieved due to the rotation and the mass movements of the various components. This can be equated with de-coupling of the inner plate section 10 from the fixed outer plate section 11 which is associated with a clear reduction of the masses to be moved during the balancing process.

(17) In order to fix the core assembly 2 in the central receiver 7 of the de-coupling plate 9, pneumatic cylinders attached to the outer plate section 11, but not illustrated, are first of all moved out. This movement of the pneumatic cylinders brings about a substantially force-free displacement of the hydraulic cylinders 8 disposed on the inner plate section 10 within a recess 16 provided in the inner plate section 11. By positioning the hydraulic cylinders, lever elements 17 adjoining the hydraulic cylinder 8 can be tilted, and this enables fixing of the core assembly 2 by means of holding flanges 18 provided on the latter.

(18) This takes place by means of a substantially axial displacement of the hydraulic cylinders 8, i.e. also axially parallel to the central axis of the core assembly 2, and this leads to tilting of the adjoining lever elements 17, as a result of which the lever elements 17 are connected to the holding flange 18 of the core assembly 2, and so the core assembly 2, in the tensed position, is fixed to the inner plate section 11. In other words, a force-fit and/or form-fit connection between the lever elements 17 and the core assembly 2 is achieved by the substantially axial or axially parallel displacement of the hydraulic cylinders 8.