Abstract:
An apparatus for removal of the liner of a self-adhesive balancing weight is disclosed. A stripper wheel or stripper belt is rotated in close proximity over the surface of a balancing weight, and interacting with the liner and pulling the liner off from the balancing weight by means of a plurality of teeth. The speed of the stripper wheel or stripper belt is slightly higher than the speed of motion of the balancing weight.

Description:
PRIORITY CLAIM  
       [0001]    This application is a continuation of pending International Application No. PCT/EP2013/053593 filed on 22 Feb. 2013, which designates the United States and claims priority from European Application No. 12160444.1 filed on Mar. 20, 2012 and European Application No. 12176445.0 filed on Jul. 13, 2012, all of which are incorporated by reference in their entireties. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to methods and devices for dispensing weights used in vehicle ballasting applications, in particular for dispensing weights used in balancing automobile or other vehicle wheels. 
         [0004]    2. Description of Relevant Art 
         [0005]    In automotive wheel balancing, individual wheel balancing weights are applied to specific positions of a rim. Basically, two types of balancing weight are used. The first kind is a balancing weight which is attached by a clamp, as disclosed in the European patent EP 1 613 876 B1, while the second kind is fixed by means of a self-adhesive tape, as disclosed in U.S. Pat. No. 6,364,421 B1. 
         [0006]    Both kinds of balancing weights are available in a plurality of sizes, resulting in different weights. When balancing a vehicle wheel, the correct size of balancing weight is selected and attached to the rim. Most balancing weights are supplied as bulk material in boxes, from which the required number of weights is manually taken. 
         [0007]    This allows for a simple, comparatively cheap supply of balancing weights. The drawback is that the person who is taking the weights from the box may take a wrong weight, and therefore a further step of balancing is required. Furthermore, the process of taking the weights can hardly be automated. Therefore, other solutions as disclosed in WO 2008/103651 A1, using a continuous polymer tape, have been developed. This has the drawback that a solid balancing weight is significantly more robust and reliable than these continuous tapes. 
       SUMMARY OF THE INVENTION 
       [0008]    The embodiments are based on the object of stripping off the liner from an adhesive tape of balancing weights without damaging the adhesive tape and further without damaging the metal surface of the balancing weight. Furthermore, peeling-off should be done automatically in large volumes for low costs. It should be reliable without residing fractions of the liner on the adhesive tape. 
         [0009]    In an embodiment, the liner is removed by a stripper wheel which rotates over the metal surface of the balancing weight, in a close proximity to be in contact with the liner but not with the metal surface of the balancing weight. Preferably, the stripper wheel rotates at a speed similar to the speed of movement of the balancing weight. Most preferably, the rotation speed of the stripper wheel is slightly higher than the speed of movement of the balancing weight. 
         [0010]    It is further preferred, if means for precise guiding of the balancing weight are provided. This improves reliability and repeatability of the stripping process and further prevents the stripper wheel to touch the metal surface of the balancing weight. Such means for guiding the balancing weight may be a pressure roller. Such a pressure roller may press the balancing weight against a surface which is further referred to as pressure plate. The pressure roller may be a single role or a belt-conveyer-like assembly having at least one, preferably two pulleys for moving the belt. Furthermore, an aspirator or a vacuum cleaning device may be provided for removing the liner from the stripper wheel. 
         [0011]    In a further embodiment, instead of the stripper wheel, a stripper belt may be used. It may be driven by at least one, preferably two stripper pulleys. Instead of a wheel or a belt, any other device having teeth at its outside and rotating with a speed similar to the speed of movement of the balancing weight may be used. Preferably, the stripper wheel or stripper pulley has saw-tooth-like teeth, which are rotating in the direction of rotation, the direction of movement of the balancing weight. 
         [0012]    In another embodiment, the direction of rotation of the stripper wheel or stripper pulley may be reversed together with a reverse order of the teeth, resulting in stripping off the liner before the stripping wheel or belt. 
         [0013]    It is further preferred, if for supplying balancing weights to the liner removal unit, a belt conveyer is provided. Such a belt conveyer may bring up the force to push a balancing weight through the liner removal unit under the stripper wheel and/or stripper belt. 
         [0014]    In a further embodiment, a plurality of stripper wheels or belts may be provided either in parallel and/or one after the other. 
         [0015]    In a further embodiment, means for adjusting the stripper wheel or stripper belt in relation to the balancing weight may be provided. This may compensate for tolerances in the thickness of the balancing weight. The adjustment may be done by spring loading the stripper wheel or stripper belt, and therefore asserting a predetermined force on the balancing weight. An alternative embodiment would be to use a stripper wheel or stripper belt having a comparatively broad surface and small teeth on it, whereas the surface is smoothly lying on the surface of the liner, while the teeth penetrate into the liner. The surface may also be made of elastic material to perfectly adapt to deviations in the surface of the liner. An alternate embodiment would be to couple the stripper wheel or stripper belt with the pressure roller or at least one of the pressure pulleys. When a balancing weight with a certain thickness is guided through the pressure roller  20 , the pressure roller is lifted to height of the balancing weight, also causing the stripper wheel or stripper belt to be lifted to the same height. This may be done by some electronic controlling or by simple mechanical coupling. 
         [0016]    The advantage of the embodiments is that the liner can be removed reliably. Furthermore, the liner may be removed at comparatively high speeds. This design allows comparatively small tolerances of the stripper wheel and/or stripper belt and means for guiding the balancing weight, which results in a comparatively small damage of the adhesive tape under the liner. Furthermore, a damage of the surface of the balancing weight can be completely avoided. This surface must not be damaged as corrosion may occur, starting at damaged sections. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    In the following, the invention will be described by way of example, without limitation of the general inventive concept, on examples of embodiment and with reference to the drawings. 
           [0018]      FIG. 1  shows a liner removal unit. 
           [0019]      FIG. 2  shows a liner removal unit with a stripper belt. 
           [0020]      FIG. 3  shows a balancing weight. 
           [0021]      FIG. 4  shows an adhesive tape in detail. 
           [0022]      FIG. 5  shows a balancing weight. 
           [0023]      FIG. 6  shows a stripper wheel in a side view. 
           [0024]      FIG. 7  shows a stripper wheel in a front view. 
       
    
    
       [0025]    While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    In  FIG. 1 , a liner removal unit is shown. For stripping off the liner  42  of a balancing weight body  41 , a stripper wheel  31  is provided. It is rotating in direction  60  which is the same as the direction of movement  14  of the balancing weight. The speed of rotation is similar to the speed of movement of the balancing weight. Preferably, the speed of rotation is slightly higher. The stripper wheel has teeth which interact with the liner  41  and  42 , and pull it away from the balancing weight. An aspirator  32  or a similar vacuum cleaning device further removes the liner  42  from the stripper wheel  31 . To prevent the balancing weight from being lifted up by slightly sticking to the liner, preferably the pressure device, almost preferably a pressure roller  20  is provided. Such a pressure roller may be a single roller. Instead, here a pressure belt  23  is driven by a pressure pulley  21  and diverted via auxiliary pulley  22 . Here, pressure builds up between the pressure roller  20  and pressure plate  24 . Pressure roller  20  may be used for precision control of the speed of motion of the balancing weight  40 , which therefore can precisely be adapted to the speed of the stripper wheel  31  or stripper belt  33 . Pressure to the balancing weights may also be asserted by the stripper wheel or its shaft, which may bend the balancing weight into a desired radius. The balancing weight is further guided by a sliding surface  51 . The balancing weight is fed into the liner removal unit by a belt conveyer  10  comprising of a belt  11 , a conveyer pulley  12 , and a support plate  13 . 
         [0027]      FIG. 2  shows a liner removal unit comparable to the unit shown in the previous  FIG. 1 . The main difference is that the stripper wheel  31  is replaced by a stripper belt  33 . Here, the stripper belt  33  has teeth  36 , which pull off the liner from the balancing weight. The stripper belt is moved by two stripper pulleys  34 ,  35 . 
         [0028]    In  FIG. 3 , a balancing weight is shown. A balancing weight body is made of a metal or a metal-plastic composition providing mass, and therefore taking the function of the weight. For fixing the balancing weight to a rim, an adhesive tape  43  is provided. For protection, the adhesive tape is covered by a liner  42  which must be peeled off before applying the balancing weight to a rim. 
         [0029]      FIG. 4  shows the adhesive tape in detail. The liner  42  is stiffer than the adhesive tape itself, while the adhesive tape consists of a comparatively elastic material. When the teeth of the stripper wheel or stripper belt penetrate through liner  42 , they also penetrate into adhesive tape  43 . Due to the elastic nature of this material, the teeth will make small cuts into this material instead of lifting the adhesive tape of the balancing weight body  41 . The liner  42  which is comparatively stiff, cannot completely be cut by the teeth, and therefore sticks to the teeth and can be removed. 
         [0030]      FIG. 5  shows a balancing weight  40  which is divided in a plurality of sections which can be separated as required. 
         [0031]    In  FIG. 6 , a stripper wheel with teeth  36  is shown in a side view. 
         [0032]    In  FIG. 7 , a stripper wheel is shown in a front view. Here, a first wheel disk  37  and a second wheel disk  38 , both having teeth  36 , are connected by a shaft  39  to rotate synchronously. It is obvious that any other number of wheel disks  37 ,  38  may be attached to a stripper wheel. The same applies to stripper belts. The shaft  39  may have a diameter slightly smaller than the wheel disks to prevent a deeper penetration of the wheel disks into the adhesive tape. 
         [0033]    It will be appreciated to those skilled in the art having the benefit of this disclosure that this invention is believed to provide balancing weights and a method for stripping a liner of an adhesive tape. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims. 
       LIST OF REFERENCE NUMERALS 
       [0034]      10  belt conveyer
 
 11  belt
 
 12  conveyer pulley
 
 13  support plate
 
 14  direction of movement
 
 20  pressure roller
 
 21  pressure pulley
 
 22  auxiliary pulley
 
 23  pressure belt
 
 24  pressure plate
 
 30  stripper
 
 31  stripper wheel
 
 32  aspirator
 
 33  stripper belt
 
 34 ,  35  stripper pulley
 
 36  teeth
 
 37 ,  38  wheel disk
 
 39  shaft
 
 40  balancing weight
 
 41  balancing weight body
 
 42  liner
 
 43  adhesive tape
 
 51  sliding surface
 
 60  direction of rotation