Balancing arrangement for rotating member and method of making same

(42) Date of commencement of the patent: 15. 4.1998 (45) Date of issue: 25.11.1998

<td>(30) Priority:</td><td>(73) Patent owner:</td>

<td>6.12.1989 US 446812 claims.</td><td>HANS OETKER AG MACHINE AND APPARATUS FACTORY</td>

<td>(56) Documents: GB 0943486A US 1705895A US 2374541A US 3901046A</td><td>CH-8812 HDRGEN (CH).</td>

<td>US 4222155A US 4237584A US 4299012A US 4340996A</td><td></td>

CQ (54) BALANCING ARRANGEMENT FOR A ROTATING PART (57) The invention relates to a balancing arrangement for a rotating part (60). with a counterweight (40) of predetermined size and weight and a clamping arrangement (10), which is so available, that it is spanned around the rotating part, to tightly engage the outer surfaces of the rotating member (60) and the counterweight (40), this being in a predetermined position, to reliably fix the counterweight to the outer surfaces of the rotating member in the predetermined position, the clamping arrangement (10) being constructed in such a way that that it has a predetermined elastic extensibility in its longitudinal direction, to compensate for temperature changes of the rotating part (60), and that the free ends (10b) of the clamping band are interconnected within a peripheral region of the clamping band, in which any weight of the compound acts as an additive to the weight of the counterweight (40), which in turn is chosen that its weight is in accordance with the imbalance in the rotating part (60).

AT 404 498

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The present invention relates to a balancing assembly for a rotating member having a counterweight and a clamping assembly made of a material lacking any significant elastic extensibility, such as made of stainless or galvanized steel, and which is stretched around the rotating part, so that it is in tight engagement with the outer surfaces of the rotating part and the counterweight, whereby the counterweight is reliably fixed to the outer surface of the rotating part.

Balancing arrangements using balance weights are known as such in the art. Various arrangements have been proposed which rely on balancing weights mounted in one or more layers determined by balancing machines which rotate the part to be balanced. These machines are known as such, for example in connection with the balancing of the wheels of motor vehicles, where balancing weights are mounted in predetermined positions on the edge of the wheel.

With the advent of power shafts for automobiles made of light metal such as aluminum or aluminum alloy, which need to be balanced, the existing method of balancing such drive shafts has been to weld balance weights of given size and weight in predetermined positions. This type of drive shaft, unlike prior art drive shafts, is constructed of hollow aluminum and has a larger diameter than the prior art solid drive shafts. Since the aluminum drive shafts have a wall thickness of about 2.2 mm, the balance weights must be welded to the outer surface of the corresponding cylindrical end of the universal joint, which has a wall thickness of about 5 mm. However, the welding operation required not only a longer cylindrical end piece of a universal joint to accommodate the largest balance weights and their welds, as will be explained in more detail below, but is also both time consuming and expensive and always entails those problems inherent in welded joints ,

A balancing arrangement of the type mentioned is known from US-PS 3,901,046. According to this document, a conventional clamping band is used, in which a clamping screw is provided in a clamping head. The thread of the clamping screw engages in narrow holes which extend substantially transversely to the clamping band, so that the clamping band is tensioned when turning the screw. If you want to use such a clamping band to compensate for imbalance of a rotating part, it turns out that the weight of the clamping head with the clamping screw is always greater than the weight that is necessary to compensate for the imbalance. For this reason, according to this document compensation weights 4 are provided, which are arranged opposite the chuck 2 in order to balance the excess weight of the clamping head. But this is used to compensate for the imbalance much material, namely on the one hand, the material for the clamping head and on the other hand, the material for the balance weights to compensate for the mass of the clamping head in turn partially. This is disadvantageous in terms of cost, weight and ease of installation. This can be seen especially in the fact that in a randomly already almost balanced rotating part of the material requirement is highest (in this case, the mass of the balance weights must be almost equal to the weight of the clamping head with clamping screw).

There is a further principal disadvantage of this known Auswuchtanrodnung: high waves, such as hollow drive shafts for aluminum vehicles can become very hot during operation. Due to these temperature changes, such hollow shafts are subject to corresponding thermal expansions; in the US-PS this problem is not recognized, and therefore no solution is proposed. In the known balancing arrangement, the clamp together with the balance weights would loosen during operation due to the thermal expansion and then rotate, so that the shaft would be anything but balanced after a short operation.

Applicant's own U.S. Patents 4,237,584, 4,299,012, and 4,222,155 disclose conventional hose clamps and do not address the problem of balancing rotating parts.

The same applies to US Pat. No. 2,374,541 and US Pat. No. 4,340,996, which describe adjustable clamps employing a pawl mechanism.

U.S. Patent No. 1,705,895 discloses a hose clamp intended for use with automobile radiators and having two or more zigzag slots 13 to provide some ductility. Also, this patent does not deal with the attachment of balance weights.

Finally, GB-PS 943 486 relates to terminals in which openings 2 are provided only to adjust the length can.

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It is therefore the object of the present invention to provide a balancing arrangement which avoids the above-mentioned deficiencies and disadvantages associated with prior art balancing arrangements and which is both simple and relatively inexpensive to install while maintaining permanent positioning of the balancing assembly Counterbalance without the requirement of welding activities.

This object is achieved by a balancing arrangement of the type mentioned in the present invention that the clamping band of the clamping arrangement to compensate for thermal expansion has at least one portion with elastic extensibility in the longitudinal direction of the clamping band and that the free ends of the clamping band are connected to each other in the peripheral region of the clamping band, where the counterweight is.

Thus, the arrangement according to the present invention is such that the weight of the chuck, which is much lighter than in US Pat. No. 3,901,046, and the counterweights cooperate (and not counteract each other) to collect the imbalance of the rotating part compensate. Thus, the present invention offers significant advantages compared to US Pat. No. 3,901,046.

In addition, according to the present invention, it is provided that the clamping band has a portion which has elastic extensibility, although the clamping band itself is made of a material which can not be elastically stretched at all. As a result, the balancing arrangement can not loosen or even twist under extreme temperature changes.

The effects of the counterweight and the additional mass in the peripheral region where the free ends of the clamping band are joined together are best enhanced if the entire counterweight is located within this peripheral region. The mass required for the counterweight is minimal in this case.

The assembly of the balancing arrangement is particularly easy if the entire counterweight is formed integrally with the connection of the free ends of the clamping band.

The counterweight and also the clamping band can be provided with an anchoring device in its inner surfaces, so that it anchors itself reliably under the tension forces that are applied by the clamping band in the outer surface of the rotating part. This anchoring device can be achieved by raw, not deburred edges, for example by using a blunt punch, when the counterweight or cut out the clamping band. However, the inner surfaces of the counterweight or clamping band may also be roughened by any known subsequent surface treatment, or such rough inner surfaces may be achieved through the use of a suitable material composition.

If the counterweight is provided with protuberances, it is expedient if the protuberances are cold-formed and form a channel which at least approximately coincides in width with the width of the clamping band to the lateral relative movement transverse to the longitudinal direction of the clamping band between this and against counterweight to a minimum.

The preferred embodiment of the elastic extensibility section is defined in the subclaims 714 and illustrated in the drawings.

In the subclaims 15-17 balancing arrangements are described, which have a separate connection part with a so-called Oetiker bracket. It can then be used preferably as part of the counterweight, the effect of which is further promoted by the oppositely arranged openings in the band, the connecting part. The clamping band in accordance with the present invention permits easy and relatively rapid attachment of the counterweight while at the same time ensuring that the counterweight is maintained in its predetermined position.

According to a further feature of the present invention, the counterweights are not flat, but may be curved with a radius of curvature that is equal to or slightly smaller than that of the rotating part. Aut this way, the counterweight adapts elastically to the outer surfaces of the rotating part, when the clamping band is tightened.

The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings which, for purposes of illustration only, illustrate an embodiment in accordance with the present invention and in which: FIG :

FIG. 1 is a plan view of a clamp assembly for use in a balancer assembly according to the present invention; FIG.

FIG. 2 is a side view of the clamp assembly of FIG. 1; FIG.

Fig. 3 is a plan view of a counterweight in accordance with the present invention;

FIG. 4 is a side view of the counterweight of FIG. 3; FIG.

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5 is a perspective view of a drive shaft with an attached balancing assembly according to the present invention;

Fig. 6 is a plan view of a modified embodiment of a clamp assembly in accordance with the present invention;

Fig. 7 is a sectional view taken along line 7-7 in Fig. 6;

8 is a sectional view similar to FIG. 7 of a modified embodiment of a clamping band according to the invention, with a concavely curved inner surface; FIG.

FIG. 9 is a perspective view of a separate connector used with the clamp assembly of FIG. 6; FIG.

FIG. 10 is a perspective view of the clamp assembly of FIG. 6 in its installed condition; FIG.

11 is a perspective view of a modified embodiment of a separate connector in accordance with the present invention integrally formed with a counterweight;

12 is a plan view of the built-in clamping arrangement comprising a connecting part according to FIG. 11, FIG.

Fig. 13 is an axial cross-sectional view through a connection of a hollow drive shaft to an end piece of a prior art universal joint, also showing a welded counterweight, and Figs

Fig. 14 is a view of an axial section similar to Fig. 13 showing the connection between a hollow drive shaft and the end piece of a universal joint, with the use of a balancing arrangement in accordance with the present invention.

Reference is now made to the drawing in which like reference numerals are used throughout the various views to designate like parts, and in particular to Figs. 1 and 2; these figures represent a clamping band, which is generally designated by reference numeral 10 and is made of stainless or galvanized steel and is provided with a number of sections, which are generally designated by the reference numeral 20 and the clamping band impart an elastic extensibility, consisting of a Material is made, which normally lacks any significant elastic extensibility in its longitudinal direction. Each section 20 here consists of two non-linear lateral band sections 21a and 21b, which are formed exclusively by cutouts from the clamping band 10. More specifically, the concave curved side surfaces 22a and 22b are formed by corresponding concave segment-like shaped cutouts along the sides of the clamping band. The inner surfaces 23a and 23b of each lateral band portion 21a and 21b are hereby formed by corresponding areas of a cutout 24 in the middle region of the clamping band, which in the illustrated embodiment has a shape which is at least approximately reminiscent of an hourglass. The non-linear side band portions 21a and 21b have a substantially constant width over at least the major part of their length, which is achieved by substantially parallel surfaces 22a, 23a and 22b, 23b. Adjacent portions are connected together by web portions 26 which extend beyond the normal width of the keying band and are bounded by the transversely extending end surfaces 25 of the central cutouts 24 of adjacent portions 20. In order to avoid peak stresses, the corners between the end faces 25 and the side surfaces 23a and 23b are rounded in this case. Similarly, the transitions from the side surfaces 22a and 22b to the normal width of the side surfaces of the belt are also rounded.

The end portions 10a and 10b, which lacks any elastic extensibility communicating portions 20, include the means for tensioning and mechanically connecting the open ends of the tensioning assembly in the tensioned condition. More specifically, the clamping band end portion 10a of the clamping band 10 is provided with two outwardly extending cold-formed hooks 31a and 31b. The opposite clamping band end portion 10b starting from its free end, provided with a rectangular opening 34 and another, cold-deformed, outwardly extending hook 35. The hook portions 31a and 35 serve with their tool engaging stop surfaces as a means for elastically contracting the ends of the clamp so that the hook 31b can engage the opening 34 when the clamping band elastically elongates by the application of tensile forces using a tool as such known for these purposes. To hold the two end portions 10a and 10b of the clamping band in mutual alignment, a tongue-like projection 36 is provided centrally in the end face 34a of the opening 34, which engages with the clamp 31b cold-deformed when the clamp is installed.

The counterweight is generally designated by the reference numeral 40 and has a predetermined weight and a predetermined configuration, for example a rectangular configuration, and comprises four cold-formed, outwardly projecting, hook-like projections 41 which between them a channel

AT 404 498 Β define with a width substantially equal to the width of the clamping band 10 to prevent the relative lateral movement between the counterweight 40 and the clamping band 10. The counterweight 40 preferably has a curved surface, which at least approximately coincides with the outer surfaces of the rotating part, to which it should be attached, and is preferably formed with a radius of curvature R, which is slightly smaller than the radius of curvature R of the outer surfaces of the rotating part, so that the clamping forces of the Kiemmanordnung the counterweight, which will cause it to be made of suitable material and / or thickness to adapt itself elastically to the radius of curvature of the rotating part. As a result, the counterweight 40, which may be provided in its inner surfaces with suitable anchoring means, will anchor itself reliably in the predetermined position to the outer surfaces of the rotating part. The anchoring means may be in the form of coarse, non-degenerate edges created by the use of a blunt tool for punching the counterweight, and / or may be produced by treating the inside surfaces by any known means to produce rough surfaces, and / or by selecting the material composition for the counterweight.

The clamping band 10 can also be provided with anchoring means to prevent the relative movement between the clamping band and the outer surfaces of the rotating part. This can be effected in a suitable manner by using a blunt punching tool to punch out of the clamping band 10 the cut-outs which lead to the elastic extensibility-communicating portions 20.

The balancing assembly according to the present invention has considerable advantages. On the one hand, it is easy to install, relatively inexpensive and relatively cheap and reliable in actual operation. On the other hand, it obviates the need for welded joints and their inherent inherent problems, as discussed in greater detail below.

The size of the counterweights and the material of which they are made may be chosen at will to meet specific requirements. As with other balancing arrangements, it will be necessary to stock a number of different sizes and weights of counterweights to allow balancing of the rotating member in the assembly according to the present invention. In addition, the relatively thin material clamping band can be made so that the overlap in the free band end region is relatively insignificant to the problem of balancing the rotating member. In addition, any imbalance resulting from the overlap may be taken into account in the construction of the counterweights, as will be explained in more detail below.

Fig. 5 illustrates a rotating member 60 in the form of a hollow aluminum drive shaft with a built-in balance assembly according to the present invention.

Using a clamping band material made of stainless steel and having an elastic limit of about 2.2 to 2.4 mm, an elastic extensibility of about 0.4 mm to about 0.5 mm per section 20 was achievable. This level of elastic extensibility was achieved, although the tensile forces in the clamping band caused the clamping band to stretch more than 0.4 to 0.5 mm per section, provided the elastic limit was not exceeded. In other words, an elastic extensibility of about 0.4 to about 0.5 mm per section is achievable, although the tape has been subjected to tensile forces causing its greater elongation, as long as the tensile forces did not cause the clamping band to exceed its yield strength.

FIG. 6 FIG. 12 illustrates a modified embodiment of a clamp assembly in which a separate connector, indicated generally by the reference numeral 130, is used to interconnect the open end portions 110a and 110b of the driver belt, indicated generally by reference numeral 110. In the in Figs. 6, 7 and 9, this separate connection part 130 comprises a plastically deformable, so-called Oetiker bail, which is generally designated by the reference numeral 136 and includes generally outwardly directed leg portions 137a and 137b which are interconnected by a bridging portion 138. The bridging portion may be provided with a reinforcing groove or, preferably, a relatively flat reinforcing embossing, as disclosed in pending US patent application Ser. 06/922 408 is disclosed on 23. October 1986 and the subject matter of which was incorporated herein by reference. The corresponding British patent application was published as British patent no. 2 160 577. The separate connector 130 comprises circumferentially directed extensions 132a and 132b provided with tab-like outwardly extending hook portions 131a, 131b, 131c and 131d which, in handling, are engageable with corresponding rectangular openings 134 which are formed in the clamping band. End portions 110a and 110b are provided.

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The clamping band 110 is provided with alternating circular and oval openings 124 and 124 'which communicate to the clamping band 110 a limited elastic extensibility in the longitudinal direction of about 0.2 mm. However, since the separate connection part 130 is provided with a plastically deformable bracket 136, the reduced elastic extensibility communicated through the openings 124 and 124 'is sufficient because the limited elastic extensibility is aided by the balancing ability of the plastically deformable bracket 136. as known in the art. The hook-like parts 131a to 131b are here tab-like parts, which are obtained by bending outwards of the strip material after substantially IIförmigen incisions. This allows the pre-assembly of the clamping band 110 and the connecting part 130 by inserting the hook-like parts 131a and 131b into the openings 134 in the end portions 110b of the clamping band 110 and then depressing the hook-like parts 131a and 131b.

The balance weight 140 is again provided with four protuberances which may be in the form of cold-formed hooks and which in turn define a channel to prevent lateral movement of the clamping band 110 relative to the counterweight 140. In the embodiment of FIG. 6 and 7, the clamping band 110 is flat, as shown in FIG. 7 shown, ie the lateral portions 122a and 122b are in the same plane as the opening 124. In contrast, in FIG. 8th the clamping band is concavely curved, which further promotes the anchoring of the clamping band in the outer surface of the rotating part and the counterweight, since the clamping band seeks to make itself under the influence of the clamping forces arising from the plastic deformation of the bracket 136.

Fig. 10 illustrates an embodiment of a balancing assembly in accordance with the present invention on a hollow drive shaft 60, in which the clamping band 110 of the type shown in Fig. 8, while the means, the elastic extensibility, with uniformly spaced, circular openings 124 exist.

FIG. 11 illustrates a combined connector and counterweight, generally designated by reference numeral 240, the counterweight consisting of two rectangular counterweight sections 240a and 240b curved as described above in connection with Figs. 1 4-4, and which are integrally formed with the plastically deformable bracket indicated generally by the reference numeral 236, which in turn may be provided with a reinforcing crimping 239 of the type described in the above-mentioned copending US application is described. The leg portions 237a and 237b are hereby connected to the counterweight sections 240a and 240b by relatively short extensions 232a and 232b (Fig. 12) formed by substantially U-shaped end cuts 242a and 242b. The tab-like hook parts 231a, 231b and 231c, 231 d are in this case integral with the respective counterweight sections 240b or 240a trained.

Figure 12 illustrates a flat clamping band 210 provided with apertures 224 and connected at the open ends 210a and 210b by a combined counterweight and connector of the type shown in Figure 11.

FIG. 13 FIG. 10 illustrates a prior art balance assembly in which a hollow drive shaft 60 is welded through the weld joint 310 to a cylindrical apron-like extension 301 of a universal joint end, generally designated by reference numeral 300. Two such universal joint end pieces are in this case welded to the ends of the drive shaft 60. This universal joint end piece 300 includes a relatively thick end wall 302 and arm portions 303 provided with connection bosses 304 machined in the arms 303. The counter or Balance weight 340 is welded to the cylindrical extension 301 by means of the welded connection 341. Since the wall thickness of the drive shaft 60 is about 2.2 mm, it is necessary to provide a relatively long, cylindrical extension 301 of about 65 mm in length having a wall thickness of about 5 mm to weld to the counterweight 340 with any required To allow size. The counterweight 340 can not be welded directly to the drive shaft 60, because with a wall thickness of only 2.2 mm there is always the risk that the weld creates holes that can occur even with a wall thickness of 5 mm. In practice, this means that the end piece 300 must be provided with a relatively long, cylindrical extension 301, which must be machined and the drive shaft assembly still brings additional weight. In Fig. 13 For example, the cylindrical extension 301 is additionally provided with a reduced shoulder 30Γ to allow the drive shaft 60 to be adapted thereabove, however, the drive shaft 60 may also be mounted inside the end piece 301.

In the balancing assembly according to the present invention, illustrated in Figure 14, a number of significant benefits can be achieved. First, the extension 301 can be shortened by about 50 mm, which in turn brings a verächtltiche saving, because the aluminum weight of two

AT 404 498 Β such end pieces 300 and the time for their machining are considerably reduced. Further, the counterweight can now be mounted at any point along the length of the drive shaft 60 in the balancing assembly of the present invention. In addition, the weld joint 310 of the drive shaft 60 in the assembly of the present invention is within the range of the solid, relatively thick end wall 302, which further favors the weld joint. The reduced diameter shoulder 301'a, which may terminate in a shallow taper, no longer serves as the sole support for the drive shaft 60, since now also supported within the range of the relatively thick end wall 302, not only provides better support for the drive shaft provides, but also a better basis for the welded joint.

As a typical, non-limiting example, six sizes of counterweights 340 may be used in the prior art arrangement of FIG. 13, namely counterweight 1 - 84 mm (width) x 50.8 mm (length) x 2.54 mm (Thickness) - 28.5 g weight.

Counterweight 2 - 70 mm (width) x 50.8 mm (length) x 2.54 mm (thickness) - 23.5 g weight.

Counterweight 3-54 mm (width) x 50.8 mm (length) x 2.54 mm (thickness) -18.0 g Weight.

Counterweight 4 - 40 mm (width) x 50.8 mm (length) x 2.54 mm (thickness) -13.0 g Weight.

Counterweight 5 - 26 mm (width) x 42.0 mm (length) x 2.54 mm (thickness) - 7.5 g weight.

Counterweight 6 - round plate with a diameter of 32 mm, 2.54 mm thickness and a weight of 5.5 g.

In the arrangement of the prior art shown in FIG. 13 These aluminum counterweights are welded to the drive shaft by means of a special machine. This temporarily requires several repetitive operations, which in turn means that the shaft must be suspended for cooling after the first welding operation and then re-examined for any residual imbalances in the cooled state. This is necessary because the shaft may experience stresses or distortions as a result of the heat that occurs during the welding operation, and new imbalances may occur in a respective drive shaft.

As stated above, it is also necessary in the arrangement of the prior art, to have at both ends of the drive shaft, an end piece with a cylindrical extension which has a length of about 65 mm and 5 mm in thickness, because the drive shaft itself has a wall thickness of only 2 mm. This is necessary in order to be able to weld the counterweights, since using a wall thickness of only 2.2 mm during the welding operation, the occurrence of holes is likely.

When using the balancing arrangement according to the invention, the end pieces of the cardan joints, via which the drive shaft is welded, can be reduced in length by about 50 mm. This offers considerable savings because the weight of the end pieces and the processing time of the end pieces can be considerably reduced.

In a non-limiting embodiment of the present invention, a clamping band made of stainless steel having a width of 10 mm and a thickness of 1 mm has been provided with a number of, for example, seven elastic-strain-splitting portions 20 of the type in Figs. 1 and FIG. 2 is shown. The open ends of this clamping band were each provided with two openings of the type which, in conjunction with the openings 134 in FIG. 6 are shown, wherein a separate connection part of the type shown in FIG. 9 shown was used to contract the open ends of the clamping band and apply the required holding forces for the underlying counterweight. If greater holding forces are required, however, the width and / or thickness of the clamping band can be increased.

The connecting part provided with the plastically deformable bail of the type shown in Fig. 9 had a weight of 4.5 g, which meant that the balancing weight could be reduced by this amount. Further, the elastic extensibility communicating portions 20 of the type shown in Fig. 1 reduce the weight in the clamp assembly with respect to the connector and counterweight, allowing for a further reduction in counterweight

In the actual embodiment described so far, the mass of the connecting part can remain the same, the mass of the clamping band can remain the same for all balancing arrangements, and only the balancing weight must be changed. In addition, the present invention allows the counterweights to have substantially the same dimensions in appearance.

To avoid confusion and confusion, the balancing assembly according to the present invention consists of an elastically stretchable stainless steel strip with identical dimensions in length, width and thickness and with identically sized, separate connecting parts with a so-called Oetiker strap "and from balancing or Counterweights that are different. According to the balancing arrangement of the present invention, the counterweights may have the following dimensions

AT 404 498 Β, the counterweight number corresponding to that used in the welded arrangement of the prior art:

Counterweight 1 - 54 mm (width) x 25 mm (length) x 2.0 mm (thickness) = 20.4 g, which exactly corresponds to the counterweight of 28.5 g, taking into account the openings in the clamping band, which are arranged opposite the counterweight.

Counterweight 2 - 52 mm x 25 mm x 1.5 mm = 14.6 g, which is exactly equivalent to the counterweight of 23.5 g, taking into account the holes in the strap opposite the counterweight.

Counterweight 3 - 49 mm x 25 mm x 1.0 mm = 9.8 g, which exactly corresponds to the counterweight of 18.0 g, taking into account the openings which are arranged opposite the counterweight.

Counterweight 4-47 mm x 25 mm x 0.5 mm = 4.5 g, which is exactly equivalent to the counterweight of 13.0 g, taking into account the openings opposite the counterweight.

Counterweight 5 - in this case, no additional counterweight is required because the clamp assembly itself produces a counterweight of 4.5 grams, and an effective counterweight of 7.5 grams can be achieved with a number of holes in the clamping band corresponding to the plastically deformable bracket are arranged opposite each other in the connecting part.

Counterweight 6 - also in this case, the counterweight is no longer required, because the clamping arrangement itself produces 4.5 g counterweight and a counterweight of 5.5 g can be realized exactly with the openings in the steel clamping band, which are opposite to the plastically deformable bracket ,

The foregoing makes it clear that the counterweights can be made similar in appearance, with only their weight being changed by changes primarily in thickness. The balancing assembly according to the present invention thus allows the use of the same connecting part with plastically deformable strap and the same strip length. By using a pneumatic, tong-like tool, the bracket can each be closed with the same closing pressure so that the different thickness of the balancing weights can be compensated by a more or less large opening of the bracket. There are also the tolerances in the drive shaft insignificant as a result of this measure.

The spring action becomes necessary to hold the balance weight in position due to the thermal expansion and contraction of the drive shaft, and is achieved by the spring action in the stainless steel clamping band and in the plastically deformable bracket, to the extent that required by the curvature of the tape itself.

The balancing arrangement according to the present invention can also be used with great advantage on the assembly line. The clamping band, the counterweight and the separate Verbindungssteii with the plastically deformable bracket are pre-assembled and pre-deformed fed in a round design. The assembler need only attach this preassembled assembly in proper position over the drive shaft, whereupon the bracket can be closed with a predetermined force by the use of pneumatic pliers. If the bracket should still protrude too far even in its closed state, the pneumatic pincer-like tool could also automatically depress the bridging member at the same time that it deforms the bracket so that the thus-deformed bracket is only minimally opposite that Drive shaft protrudes.

It should be noted that the above example merely explains the present invention and means no limitation thereto; rather, the invention is susceptible of numerous modifications, as will be readily apparent from the above.

While several embodiments have been shown and described in accordance with the present invention, it is to be expressly understood that it is not limited thereto but capable of numerous changes and modifications as would be understood by those skilled in the art. For example, the configuration of the elastic stretch communicable portions may be changed as desired to achieve specific results, all that is required is that such an arrangement be made that the desired elastic extensibility is achieved and the effective balance or Counterweight, as required, is produced. In addition, the present invention is not limited to use with rotating parts made of aluminum, but may also be applied to rotating parts made of other metallic materials or their alloys, as well as those made of plastic or other exotic ones or. made of unusual materials, such as a high temperature sintered material.

The invention is thus not to be limited to the details shown and described herein, but is intended to cover all such changes and modifications as come within the scope of the disclosure

AT 404 498 Β are encompassed.