Patent Application
20130224449
The invention relates to an adhesive balancing weight consisting of an adhesive tape system and at least one weight body, wherein the adhesive tape system has a tape base between a first adhesive layer and a second adhesive layer. The invention further relates to an endless adhesive weight consisting of adhesive balancing weights of this type, arranged in a row.
Adhesive balancing weights are used for producing an optimal moment of inertia in a rotating machine part (rotational body), particularly in a vehicle wheel, for example, the rim thereof. Unbalanced machine parts can run untrue, a situation which cannot be avoided during production, or which can even is arise later as the machine part is operated. Therefore, as part of a balancing process, the position and the necessary weight of an adhesive weight are determined, and said adhesive weight is adhesively attached at an appropriate location on the machine part. In this manner, a situation can be prevented in which the machine part might exert damaging force on its own bearing during operation, or might even lead to failure of the machine, or at least of the machine part.
Vehicle wheels are ordinarily balanced following tire replacement, in order to compensate for any discrepancies in rotational symmetry in the weight distribution of the tire, particularly of the outer surface of the tire, and thereby to ensure true running. Imbalance is understood as the non-uniform distribution of mass on a rotating machine part, as in the mentioned vehicle wheel, for example.
In practice, imbalance is compensated for by means of an adhesive balancing weight or multiple adhesive balancing weights, by fastening said weights at a position on the wheel rim that is to be determined in each case. In this manner, vibrations during rotational operation are avoided, which can damage the wheel bearing and the vehicle axle as a result of increased wear and tear on tires and bearings, but also on other parts of the vehicle chassis. On front wheels, such imbalance can also lead to “shimmying” of the steering wheel, which results in pronouncedly dangerous steering behavior with poor directional and cornering stability, and which disadvantageously decreases driving safety.
From German patent disclosure 1 605 584, balancing weights for pneumatic vehicle tires are known, which weights have an adhesive tape system having a layer of foam as the tape base. In this case, the function of the tape base is to compensate for irregularities in the adhesive surface, and to press the adhesive layer provided for fastening uniformly onto the uneven surface for adhesion. However, it is disadvantageous in this case that, although the adhesive balancing weight can be removed after use, foam from the tape base will be left on the adhesion surface of the tire, thereby leaving an extremely unsightly soiled area on the previous adhesive surface. Chemical after-treatment is required for removing the foam, resulting in additional expense, and also in harm to the environment.
EP 0 535 098 B1 proposes inserting a mesh structure into the outer, second adhesive layer of the tape base material, which mesh structure acts as a protective coating on the tape base when the adhesive tape system must be removed after adhesion. As a result, only an adhesive residue is left on the surface, which ideally is transparent or colorless, and is therefore unnoticeable. In this case, it has still proven disadvantageous that information about the adhesive balancing weight or other information relating to the product can no longer be easily applied to the adhesive balancing weight so as to be legible.
Applying the information to the weight body is difficult, as this would require stamping or additional adhesion, in other words, at least one additional process step. Applying the information to the liner—a protective film on the outer adhesive layer, which is removed prior to adhesion—is also disadvantageous, because when the adhesive balancing weight is reused, said liner is already missing.
The problem addressed by the invention is that of providing an adhesive weight, which can be easily removed from an adhesive surface without leaving any residue and in an environmentally safe manner.
The problem is solved with an adhesive balancing weight of the type specified in the introductory portion in that the tape base is embodied as a first base film.
The adhesive balancing weight has an adhesive tape system. This adhesive tape system has a base film for the structural reinforcement of the adhesive tape system, wherein the weight body, particularly a metal strip or a metal leaf, is fastened to the adhesive tape system by means of a first adhesive layer. The base film can optionally also be used to compensate for the irregularities in an adhesive surface onto which the adhesive tape system is to be fastened via the second adhesive layer, by way of the choice of the material, for example, polyester or polyethylene, and the choice of a thickness of the base film.
The weight body is made, for example, of metal, particularly zinc, or of a metal alloy. More particularly, the weight body has a primarily inflexible, flat surface, and therefore, the base film must ensure that the adhesive pressure that is necessary for adhesion is provided as uniformly as possible across the adhesive surface, so that the second adhesive layer can adhere across the largest possible surface of and securely to the machine part, particularly the wheel rim. Alternatively, in addition to the base film, a leveling layer can also be provided, which allows adaptation to the adhesion surface, thereby allowing the base film to be designed as thinner and specifically for reinforcement (separation of functions).
According to the invention, it is provided that a base film is arranged between the first and second adhesive layers. It is also entirely possible for additional layers to be provided, which separate the stated adhesive layers, or the base film and one of the two adhesive layers, from one another. In other words, it is not essential for the aforementioned adhesive layers to border the base film. In this, it is advantageous for the film to be easily produced, and to have very high structural stability, which can be supported by material stability, such as with polyester or polyethylene, for example.
In addition, if a leveling layer is provided, said layer can be protected by the base film. If the balancing weight is improperly fastened, the weight can be removed again because the leveling layer, unlike other tape bases of the prior art, can be protected by the base film. When it is pulled off, the structural integrity of the leveling layer is maintained. Advantageously, the base film is made of plastic, ideally of polyester or polyethylene. This material is stable enough to protect the leveling layer or other layers of the adhesive tape system.
The adhesive tape system is advantageously equipped with a removable protective film (a “liner”), which adheres to the outside of the adhesive tape system on the second adhesive layer. This liner ensures that the adhesive of the second adhesive layer cannot become unnecessarily soiled, and also that an endless tape or an endless chain of adhesive weights can be advantageously rolled up, without adhering to one another.
Preferably, the first base film is provided for carrying information, wherein the second adhesive layer is made of a transparent adhesive, particularly a transparent acrylic adhesive. Therefore, prior to production of the adhesive tape system, the base film can be easily provided with information or with multiple pieces of information using the simplest, known methods. For this purpose, it is necessary only to ensure that the adhesive of the second adhesive layer is transparent, and will not darken, even after a certain period of storage. In addition, the protective film that adheres to the outside should also be transparent, to ensure that the information is legible.
For example, the information could be imprinted onto the first base film, applied using a laser beam, or punched out of the base film. All of these are established, cost-effective and time-efficient methods, which can be used to easily apply information to the adhesive tape system. This information is then permanently associated with the adhesive balancing weight. A labeling of the adhesive balancing weight as understood in a broader sense is thereby accomplished.
In an alternative embodiment, the information can be imprinted onto the leveling layer, applied to the leveling layer using a laser beam, or punched out of the leveling layer, wherein the base film is embodied as transparent. Although the leveling layer already has a function, said layer can nevertheless be used as an information carrier. This embodiment might be costly in industrial terms, however, it could still result in a corresponding advantage over the aforementioned embodiment in which the base film carries the information, depending upon the intended use. In any case, the concept of the invention also offers this option.
The information can be embodied as at least one number, at least one letter, a computer readable code, an ideogram, and/or a symbol, particularly a logo, a word mark or a design mark. Any combination of the stated types of information can also be implemented, wherein multiple pieces of information can also be applied to the base film. Said pieces of information can have different forms, such as a serial number or an order number, for example. The manufacturer could be identified, or an indication regarding a property of the adhesive weight could also be applied as information, such as the weight of the weight body, or the length of the associated endless strip, for example, or simply information or instructions as to how the adhesive weight is to be used, for example, using an ideogram.
The aforementioned marks (word mark and/or design mark) refer to identifying marks, particularly legally protected identifying marks, which can supply the consumer, for example, with information about the manufacturer or about the quality of the product.
Advantageously, a plurality of weight bodies are positioned in a row on the adhesive tape system and are separated from one another by a notch, thereby supporting a curving of the composite, for example, when endless adhesive weights are rolled up, or a curving of the machine component or of the wheel rim.
In one advantageous embodiment, the first base film is embodied as magnetic. This can be accomplished by applying magnetic or magnetizable particles, which are incorporated, together with the base film, into the adhesive tape system. Alternatively, magnetic, particularly permanently magnetic, ribs can also be threaded into the base film. This facilitates handling of the balancing weight, because the adhesive balancing weight is easier to grip. This is particularly relevant shortly after application, before the adhesive of the second adhesive layer has hardened or dried. Without a magnetic effect, a subsequent, undesirable displacement of the balancing weight is much more probable.
If the first base film is embodied as magnetic, the adhesive balancing weight is also suitable for automated application, due to its magnetic support. In this case, it is not necessary to wait for the adhesive, or for the development of the adhesive effect thereof. The adhesive balancing weight is held securely in position, even immediately after its attachment to a magnetic adhesive surface. Only later is the position also secured by the adhesive.
The leveling layer is preferably embodied as flexible, in order to optimize adaptation to irregularities in the adhesive surface and thereby compensate for the rigidity of the weight body. For this purpose, the leveling layer can be made partially or entirely of foam or foam rubber, because these substances are cost-effective and can be easily applied. The leveling layer is disposed between the first adhesive layer and the second adhesive layer, so as to achieve the leveling effect with respect to the irregularities in the adhesive surface on the machine part from the adhesive tape system.
Advantageously, the leveling layer is made partially or entirely of foam, particularly of polyethylene foam (PE foam) or foam rubber. These materials are characterized by material stability and insusceptibility to chemicals.
The leveling layer preferably borders the first base film and/or the second base film. Adhesive tape systems having two base films make it possible to use a plurality of functional layers, without destroying the adhesive tape system, allowing the adhesive tape system to be entirely removed from an adhesive surface without leaving any residue behind.
If the first base film is disposed between the second adhesive layer and the leveling layer, then when the system is pulled off, all tearing force is exerted on the base film, which is designed to be structurally highly stable, and therefore only the second adhesive layer is separated and remains partially on the first base film and partially on the adhesive surface of the machine part. This protective effect is further intensified if the first base film borders the second adhesive layer and the leveling layer.
The leveling layer preferably borders the first adhesive layer, the second adhesive layer or a third adhesive layer, which is disposed between the first and second adhesive layers. If the leveling layer is protected by the base film, it is advantageous in terms of the leveling function for said layer to be arranged as close as possible to the second adhesive layer or to the machine part. Thus, when it borders the first adhesive layer, a more cost-effective adhesive tape system results, which tends to have fewer layers. In contrast, if it borders the third adhesive layer, the leveling layer is very well protected on both sides against tearing when the balancing weight is being pulled off. Such a protection of the leveling layer can be achieved particularly by disposing a second base film between the leveling layer and the first adhesive layer, because the base films protect the leveling layer from two sides, in other words, said films are arranged in a quasi sandwich structure.
The use of an endless adhesive weight consisting of adhesive weights according to the invention arranged in a row offers additional advantages. In this case, the adhesive weights are provided rolled up and intended to be separated from one another for adhesive use, particularly by means of repeated perforations on a continuous adhesive tape system. Thereby, the automated use of the adhesive weights is possible, most advantageously in combination with a balancing assembly involving a subsequent fastening of the adhesive balancing weight or the adhesive balancing weights onto the machine part.
Additional advantageous further developments and preferred embodiments of the invention are found in the description of the figures and/or the dependent claims.
The drawings show:
The second adhesive layer 3 is formed by a transparent acrylic adhesive and possesses an adhesive force which is capable of holding the adhesive tape system with weight bodies 8 in the adhered state, for example, on an adhesive surface 10. In
In
The adhesive balancing weight of
The adhesive balancing weight of
Adhesive layer 5 should preferably be embodied as having a stronger adhesive than adhesive layer 3, so that pulling off after adhesion will not lead to a separation of the adhesive system into two parts, and instead, only adhesive from the adhesive layer 3 will remain stuck to the rim or the machine part.
The embodiment examples of
The adhesive layers of
The simplest embodiment example of
Alternatively, the weight body 8 can consist of an elastomer, which is filled or doped with metal. An elasticity is thereby produced which allows the adhesive balancing weight to adapt to irregularities in the adhesive surface 10, such as screw heads, grooves, edges or holes. Thus the elastomer-based weight body 8 replaces the leveling layer 6, in that said weight body assumes the function of compensating for irregularities.
Common to all embodiment examples of
The embodiment examples of each of the figures have at least two adhesive layers, wherein adhesives of different strengths can be used for these adhesive layers, in order to define the adhesive layer for a subsequent separation of the adhesive balancing weight from the adhesive surface, by means of the weaker adhesive. The adhesive tape system can also have three, four or more adhesive layers, wherein ideally the second adhesive layer 3 is the adhesive layer that contains the weakest adhesive. Therefore, it is always ensured that the adhesive tape system can be separated at the second adhesive layer 3.
In summary, the invention relates to an adhesive balancing weight 1 having an adhesive tape system, wherein the adhesive tape system is formed from a tape base between a first adhesive layer 7 for fastening the weight body 8 onto the adhesive tape system and a second adhesive layer 3 for fastening the adhesive balancing weight itself. When the adhesive weight is pulled off, no layer should be damaged, particularly not the vulnerable leveling layer, in order to avoid leaving any remnant behind on the adhesive surface. This is achieved, while maintaining the customary advantages of an adhesive weight of this type, by embodying the tape base as a first base film 4.
