Field of the invention

The invention relates to a manually operated dispensing device for balancing weights, preferably for balancing weights for vehicle wheels.

Description of the related art

Self-adhesive balancing weights having a weight body, comprising a mass material and a self-adhesive tape for attaching the balancing weight to a rim are dis- closed in EP 1 355 084 Al and in EP 1 039 169 Al. The balancing weights are delivered in boxes, each box containing a plurality of balancing weights. The balancing weight bodies have segments, which allow cutting off or breaking off pieces of the balancing weight body, therefore reducing or modifying the mass of the balancing weight according to the required mass. These balancing weights allow simple handling and storage, although the disadvantage is that a significant amount of the mass material is wasted. If, for example, the total of mass of the balancing weight body is 60 grams, and only 25 grams are needed for balancing, then 35 grams are wasted.

US 7,931,342 B2 and US 6,547,338 B2 disclose adhesive wheel weight dispensing apparatus, where a cutting member is movable by a pneumatic cylinder and balancing weights. They are fed by balancing weights on a reel. There, a large number of individual balancing weights are attached to a common self-adhesive tape. This common self-adhesive tape holds the individual balancing weights together and forms a belt of balancing weights, which is cut into smaller pieces by auto- mated cutting and handling devices. The smaller pieces of balancing weights are individually cut according to the requirements for each vehicle wheel, during the balancing process of the wheel. Therefore, such automated balancing weight dispensing machines are preferably used in automated balancing weight devices, which are often used at car or tire manufacturers. EP 1 253 414 A2 discloses a further automated dispenser with a pneumatically operated cutter.

A small tire workshop cannot afford a high performance automated balancing weight dispensing machine as described before. These machines are too expensive and require a significant amount of maintenance.

Summary of the invention

The problem to be solved by the invention is to provide a low cost dispenser for balancing weights, which is manually operated and which allows dispensing of balancing weights having masses individually adapted to a specific tire and/or rim and having a low waste of balancing weight material. Furthermore, the dis- penser should be usable by persons without special training. It should be simple and gave no or at least a very small number of serviceable parts.

Solutions of the problem are described in the independent claims. The dependent claims relate to further improvements of the invention.

A manually operated balancing weight dispenser can be provided at significantly lower costs compared to the automated high performance balancing weight dispensers as known from the prior art. The balancing weight dispenser uses balancing weights where individual balancing weight bodies are attached to a common tape carrier, forming a belt of balancing weights. This balancing weight belt is stored in or on a storage space provided in or at the dispenser. Preferably, the balancing weight belt is wound on a reel. In an alternate embodiment, it may also be stored in a box where the balancing weights are stacked in separate lay- ers. The belt of balancing weights is guided by a belt guide to provide the belt of balancing weights and therefore the balancing weights in a given position to the operator. Furthermore, a cutter is provided. It is preferably located at the end or within the belt guide. For delivery of a required amount of balancing weight mass, the belt of balancing weights is pulled from the reel or stack until the desired number of balancing weights has been obtained. In the next step, the belt of balancing weights is cut, preferably between two adjacent balancing weights, to separate the selected portion of balancing weights from the remaining belt of balancing weights. The remaining belt is placed or falls back to the guide and remains in a desired position for receiving the next portion of balancing weights.

In a preferred embodiment, the cutter comprises a fixed knife for cutting the balancing weight belt and therefore for preferably cutting the self-adhesive tape and/or the liner. Cutting may be performed by sideward pushing the belt of bal- ancing weights towards the cutter, whereas preferably the cutting knife is positioned between two adjacent balancing weight bodies. This ensures that the belt of balancing weights is cut at a position between two adjacent balancing weights. Preferably, the knife is fixed to the balancing weight dispenser or a support being part of the dispenser. Most preferably, the knife is not movable against balancing weight dispenser or the support.

Preferably, the cutter is simple module, which can be exchanged, when the knife is blunt. Preferably, the cutter has a solid base plate, which holds a knife. The knife may be clamped, glued, welded, or soldered to the cutter base plate. Furthermore, it is preferred, if the cutter base plate forms a cutting slot through which the belt of balancing weights in inserted for cutting. It is preferred if this slot is wide enough for inserting the belt of balancing weights. On the other hand, it should be comparatively narrow to prevent a finger or other body part of the operator from being cut by the knife and therefore prevents injuries.

In another preferred embodiment, a guide is provided which guides the belt of balancing weights, such that the knife is located in a position between two adja- cent balancing weights, and therefore avoids blocking or damaging of the knife by a balancing weight body. This guide may be a wedge- of funnel-shaped means, which guides the belt of balancing weights, which is moved towards the knife, such that the knife is automatically positioned between two adjacent balancing weight bodies. In another embodiment, the guide may simply block pushing balancing weights at a position of a balancing weight body towards the knife and would allow pushing the belt of balancing weights at a position between two adjacent balancing weights towards the knife.

In another embodiment, at least two dispensers are arranged to a dispenser as- sembly. This allows delivery of at least two different kinds of balancing weights to provide for a backup with a second dispenser for the case the first dispenser fails, which may be caused by an empty reel of balancing weights or by a damaged cutter.

It is furthermore preferred to have a container attached to a balancing weight dispenser, which may be used for collecting balancing weight waste, like unused balancing weights, tape pieces, or liner pieces.

In another preferred embodiment, at least one balancing weight dispenser is mounted to a stand, which holds the balancing weight dispenser in a suitable user-friendly position to allow easy access to the balancing weights.

In a preferred embodiment, the balancing weights are held on a tape carrier, which preferably is a self-adhesive tape, which is provided at one side of the bal- ancing weight bodies for holding the balancing weight bodies to a rim. The side of the self-adhesive tape opposite to the balancing weights may be protected by a liner.

In another preferred embodiment, each balancing weight or a small number of balancing weights bear individual self-adhesive tapes, which are connected by a common tape carrier. This common tape carrier may also have the function of protecting the adhesive side of the self-adhesive tape pieces opposite to the balancing weights. It may be a liner.

In another embodiment, a movable knife is provided. This knife may be manually operated by a leaver or it may be operated by an electrical motor, an electric or pneumatic actuator. Movement of the knife may be either manually triggered by a trigger, a switch or a valve which is released by the operator. It may also be triggered by a sensor, like an optical sensor, a mechanical sensor, or a magnetic sensor. Such a sensor may detect the presence of the balancing weight belt and therefore trigger the knife to cut the belt of balancing weights. It is preferred, if triggering of the knife is only enabled if the knife is between two adjacent balancing weights.

In another embodiment, a means for moving or pushing the belt of balancing weights to or through the knife may be provided. Such a means for pushing may also be operated by a leaver, which is operated by the operator or by an electrical motor, an electrical or pneumatic actuator. It may also be triggered automatically as described before.

In another embodiment, the cutter may be enabled to cut not only the tape, but also a balancing weight body. This would require a much more solid cutter and/or a much more solid knife. On the other hand, this would allow selecting even portions of a balancing weight, and therefore allowing for a much more precise balancing. Description of Drawings

In the following, the invention will be described by way of example, without limitation of the general inventive concept, on examples of embodiment with refer- ence to the drawings.

Figure 1 shows a balancing weight dispenser assembly according to a first embodiment.

Figure 2 shows the first embodiment in a different perspective view. Figure 3 shows the previous embodiment in a side view. Figure 4 shows the embodiment in a top view.

Figure 5 shows a balancing weight dispenser assembly mounted to a stand. Figure 6 shows a cutter in detail.

Figure 7 shows a belt of balancing weights in a first embodiment. Figure 8 shows another embodiment of a belt of balancing weights. Figure 9 shows the cutting process in detail. Figure 10 shows a modified embodiment. Figure 11 shows another embodiment.

In Figure 1, a balancing weight dispensing apparatus according to a first embod- iment is shown. A first balancing weight dispenser 10, a second balancing weight dispenser 20, and a container 30 are assembled to a first balancing weight dis- penser assembly. The first balancing weight dispenser 10 is basically the same as the second balancing weight dispenser 20. Therefore, only one balancing weight dispenser is described in more detail. For holding a reel 41, as later shown, a pair of reel holders 11, 21 is provided. Preferably, each reel holder has a pivot guide slot or hole 15, 25. For guiding the belt of balancing weights, a belt guide 12, 22 is provided. Furthermore, a cutter 13, 23 is provided and preferably arranged at the end of the belt guide 12, 22. For stabilizing the belt guide and holding the cutter in place, a support 14, 24 is provided. Although the invention is not limited to this simple design, a part of the body of the balancing weight dispenser to- gether with the belt guide and the support forms a stable triangle and gives a rigid support for the cutter. There is at least one mounting slot or hole 16, 26 to attach a plurality of balancing weight dispensers together and/or to attach them to a stand 50, as shown later. The body the balancing weight dispenser forms a balancing weight storage space 18, 28, which may hold a reel of balancing weights or a stack of balancing weights.

In Figure 2, the previous embodiment is shown in a different perspective view. Here, the belt guide 12, 22 can be seen in more detail. Preferably, the belt guide has at least one recess 17, 27 which simplifies access to and quitting of the belt of balancing weights. In Figure 3, the previous embodiment is shown in a side view. Furthermore, a reel 41 holding a belt of balancing weights 40 is shown. In this embodiment, the reel 41 has a pivot 42, which is held by the pivot guide slots 25 in the balancing weight dispenser.

In Figure 4, the embodiment is shown in a top view. Here, a reel 41 is only insert- ed into the second balancing weight dispenser 20, while the first balancing weight dispenser 10 is empty. It can be seen, how the recess 27 simplifies gripping of the balancing weights of the belt of balancing weights 40. For this pur- pose, the width of the belt guide 22 at a position of the recess 27 is narrower than the width of the balancing weights. For receiving a balancing weight, the belt is pulled into the direction indicated as x, which is also the direction, in which the belt of balancing weights unwinds from the reel. For cutting, the belt is inserted into the cutter between two adjacent balancing weights and moved sideward into the direction perpendicular to the first direction, here marked as y. The cutter may also be mounted in the opposite direction, so that the cutting operation may be done in the opposite direction.

In Figure 5, a balancing weight dispenser assembly is shown mounted to a stand, which holds the balancing weight dispenser assembly in a favorable position for easy access. The stand 50 preferably has a base 51 for stabilizing the stand on a floor. The stand 50 furthermore has a body 52 with a lower section 53 and an upper section 54. Preferably, the lower section 53 has an opening, which may be used to hold a waste container for spare balancing weights. It is further preferred if the upper section 54 has a plurality of holes 56 which allow the insertion of pins or wires, or other devices for holding tools. Therefore, a plurality of tools, which may be used for mounting and removing of balancing weights, may be held by the upper section of the stand.

In Figure 6, a preferred embodiment of a cutter is shown in detail. The cutter has a solid base plate 60, which holds a knife 61. The knife may comprise several cutting sections. Preferably, the knife 61 is clamped, glued, welded, or soldered to the cutter base plate. The cutter base plate forms a cutting slot 64 through which the belt of balancing weights in inserted for cutting into the direction indicated as x. It is preferred if this slot is wide enough for inserting the belt of balancing weights. On the other hand, it should be comparatively narrow to prevent a finger or other body part of the operator from being cut by the knife and therefore prevents injuries. It is further preferred if there is a guide 62 at the cutting slot, guiding the belt of balancing weights, such that the belt of balancing weights is cut between two adjacent balancing weights. In this embodiment, the guide 62 simply limits the height of the cutting slot and does not allow inserting of the belt of balancing weights at the position of a balancing weight into the cutting slot. Instead, the height-limited cutting slot is wide enough for inserting the belt of balancing weights at a position between two adjacent balancing weight bodies. Furthermore, it is preferred if the guide 62 slightly separates two adjacent balancing weight bodies to simplify cutting. Preferably, a cutter is a simple module which may be attached by at least one mounting slot or hole 63 to a balancing weight dispenser. Most preferably, the cutter has no user replaceable parts. Therefore, it should not be possible to replace the knife by a user. Instead, the cutter is exchanged as a whole part. Due to its symmetric mounting slots, the cutter may be mounted in different directions to allow inserting of the balancing weight string from two opposite sides along the y-axis or opposing thereto. This is specifically useful in an embodiment as shown in figure 4 with two closely mounted dispensers. Here, the string may be inserted into cutter 13 in the y- direction, whereas the string may be inserted into cutter 23 in a direction opposite to the y-direction.

In Figure 7, a belt of balancing weights 70 in a first embodiment is shown. The belt of balancing weights 70 comprises a plurality of balancing weight bodies 71, which are positioned on a self-adhesive tape 72. The side of the self-adhesive tape 72, which is opposite to the balancing weight bodies 71, is protected by a liner 73.

In Figure 8, another embodiment of a belt of balancing weights is shown. Here, each balancing weight body 71 has a segment of self-adhesive tape 72. There is sonly a common liner 73 to protect the self-adhesive tape and to form a belt of balancing weights by holding the balancing weights and their self-adhesive tapes together. In this embodiment, it is no more necessary to cut the self-adhesive tape, which sometimes can be difficult due to the adhesive properties. Instead, only the non-adhesive liner has to be cut.

In Figure 9, a process of cutting the belt of balancing weights is shown in detail. Here, the knife 60 penetrates in-between two balancing weight bodies 71 and cuts the self-adhesive tape 72 together with the liner 73.

Figure 10 shows a modified embodiment with a modified reel holder 21.

Figure 11 shows another embodiment with a box 45 holding the string of balancing weights. The box may have an internal reel, although this is not required. There may be cut out in the reel holder 21 showing a marking 46 of the box, which may indicate the type of balancing weights in the box or give any other useful information.

List of reference numerals

10 first balancing weight dispenser

11 reel holder

12 belt guidance

13 cutter

14 support

15 pivot guide slot

16 mounting slot

17 recess

18 balancing weight storage space

20 second balancing weight dispenser

21 reel holder

22 belt guidance

23 cutter

24 support

25 pivot guide slot

26 mounting slot

27 recess

28 balancing weight storage space

30 container

40 belt of balancing weights

41 reel

42 pivot

45 box

46 marking

50 stand

51 base 52 body

53 lower section

54 upper section

55 opening

56 holes

60 cutter base plate

61 knife

62 guide

63 mounting slot

70 belt of balancing weights

71 balancing weight bodies

72 self adhesive tape

73 liner

x direction for pulling balancing weights from reel or stack y direction for cutting