The present invention relates to a system for girding articles, in particular the twisted necks of filled plastic bags, according to the preamble of claim 1.

Systems according to the preamble for closing bags and the like are known from, inter alia, American patent specifications US 3,729,896 and US 4,718,220. These manually operated bag-closing devices are currently used for domestic purposes in particular. With the device according to US 3,729,896, a closure consisting of a single strip of self-adhesive tape is applied around the twisted neck of a bag. With the device according to US 4,718,220, the ends of the self-adhesive tape facing away from the neck of the bag are covered with a strip of paper tape, which greatly facilitates the reopening of the bag. The object of the present invention is to improve the known systems, and in particular to make them more suitable and acceptable for professional applications such as in the retail trade or in industry. In industry such devices can also be used for, for example, girding a bunch of cables.

This object is achieved according to the present invention by providing a system according to the preamble of claim 1, which is characterized in that the girding device and the roll of adhesive tape and/or the roll of paper tape are designed in such a way that the roll in question can be placed in only one position in the girding device.

The invention is based on the fact that the roll of tape often runs out at times when the device is being used the most intensively. This means that the empty roll then has to be quickly exchanged for a new roll, for example in the retail trade when customers are standing waiting in the shop. However, the known systems allow the roll of adhesive tape, and also the roll of paper tape if present, to be placed in an incorrect position in the girding device in the first instance, so that the device jams during the next

use. The correction then needed leads to time loss and irritation. This inefficiency of this system in practice has led to other, more expensive and more time-consuming ways of closing bags, for example by means of loose plastic clips, being used on an increasingly large scale.

Although it is not difficult per se to place a loose roll of tape correctly in the girding device, where such systems are being used in, for example, the retail trade, another problem is the fact that a large number of the personnel are employed only temporarily, and are consequently unfamiliar with the way in which the device works. The measure according to the invention means that no experience or knowledge of the system whatsoever is necessary for replacing the loose roll or rolls of tape quickly and without any problems.

It is clear that the idea of the invention can be achieved in many different ways, for example by arranging for a wall of the device situated next to the roll of tape during normal operation of the device to be provided with lug means pointing towards the roll, and by making the core of the roll of tape in such a way that at the side intended for lying along said wall of the device it is provided with a circumferential groove into which the lug means project, and at the opposite side making it in such a way that the lug means cannot project into the core there.

In a specific embodiment, the lug means can be formed by an annular wall, projecting from the wall in question. In another embodiment the lug means can consist of individual lugs arranged in a circle. The idea of the invention is particularly advan¬ tageous in the case of a girding device of the type described in American patent US 4,718,220, in particular if the idea of the invention is being used to ensure that it is not possible to place the loose roll of paper tape in the incorrect position in the device. For if the roll of adhesive tape is placed incorrectly, the fact that the device is not functioning will make it clear that a mistake has been made, but the roll of paper tape will still unroll in the wrong position. In practice, however, there is the

risk that if the roll of paper tape is placed incorrectly, the easily tearing paper tape in the device may run over a sharp corner not intended for it, and will then still tear as a result of the jerking movements exerted on the paper tape during use.

The present invention will be explained in greater detail below with reference to the appended drawing, in which:

Fig. 1 shows a view in perspective, partially cut away, of a girding device of the system according to the invention;

Fig. 2 shows a side view of the device in Fig. 1, in which the fold-down wall thereof is omitted; and

Fig. 3 is a section along the line III-III in Fig. 2 during normal use of the system according to the present invention.

Figures 1 and 2 show a girding device 1 according to the invention, having a plastic housing 4 which consists of a housing part 2 with support foot and a cover 3 (shown only in Figure 1) which is fitted on the housing part 2 in such a way that it hinges about a hinge pin situated near the bottom edge thereof. The housing 4 has a slot 5, beginning at the top side thereof and extending in the direction of the support foot, through which slot a twisted, or otherwise compressed, neck 6 of a bag is moved from top to bottom, in order to place a closure around the neck 6 of the bag.

The housing 4 is provided with a support 7 for rotatably supporting a roll of single-sided adhesive tape 8, which is indicated by dashed lines in Figure 2. The housing 4 is also provided with an essentially identically designed support 9, for rotatably supporting a roll of paper tape 10, which is likewise indicated only by dashed lines in Figure 2. The device also comprises a star wheel 11 with radially extending spokes, between which recesses are present, in which recesses the neck 6 of the bag to be closed comes to lie while passing the star wheel 11. The star wheel 11 is rotatably mounted on a shaft 12 formed on

the housing part 3, in such a way that the spokes of the star wheel 11 extend over the slot 5 up to the other side of the slot 5. At that side the housing part 3 contains an element 13 which forms a curved wall part 14 situated near the path of the tips of the spokes of the star wheel 11.

Past the star wheel 11, viewed in the direction of movement of the neck 6 of the bag, a tilting arm 15 extends over the slot 5, which tilting arm 15 forms part of cutting element 16. The cutting element 16 is tiltable about a shaft 17 fixed securely to the housing part 3, and is held in the position shown in Figure 2 by means of a return spring 18. When the neck 6 of the bag pushes away the tilting arm 15 out of the slot 5, a cutter 19 fitted on the cutting element 16 moves into the slot and severs the closure formed around the neck 6. For a detailed descrip¬ tion of the operation of the device and the formation of the closure around the neck 6 of the bag, reference is made here to US Patent 4,718,220.

The idea of the invention will now be explained with reference to Figures 2 and 3. It is pointed out here that the supports of the roll of paper tape and the roll of adhesive tape, and also the cores of both rolls, in this exemplary embodiment of the system according to the invention are of generally identical design, which is the reason why a description of the way in which the roll of paper tape and the parts of the device interacting therewith are designed will suffice.

It can be seen in Figure 3 that the paper tape 10 is wound onto a core 20. The core 20 is a plastic ring in which a circumferential groove 21 is formed at one of the two sides situated at right angles to the axis of rotation, while the opposite side of the core 20 is of essentially closed design, and in particular is not provided with an equally deep or even deeper circumferential groove. The core 20 has a cylindrical bore with a standard internal diameter, in particular up to 2.5 inches.

For rotatably supporting the roll of tape 10, parts which can project into the bore of the core 20 are formed in a manner known per se on the housing part 2. These are

two curved wall parts 23 and 24 which are disposed in a rigid manner diametrically opposite each other on the housing part 2, and also two resilient lips 25 and 26 situ¬ ated diametrically opposite each other. The lips 25 and 26 each bear at their free end an outward projecting thickened part 27 and 28 respectively. When the core 20 is inserted over these parts 23, 24, 25 and 26, the lips 25 and 26 first move inwards, and then move outwards again, and grip with their thickened parts 27 and 28 respectively over the core 20, thus holding the core 20 in place.

An inward projecting annular wall 30, lying around the outside of the parts 23, 24, 25 and 26 projecting into the bore of the core 20, is formed on the inside wall of the housing part 2. The annular wall 30 is of such dimensions and is placed in such a way that said annular wall 30 projects into the groove 21 of the core 20 if the roll of tape 10 has been placed in the correct position in the device. In this correct position, shown in Figure 3, the roll of tape can rotate with slight friction. It is clear that if a mistaken attempt is made to place the roll of tape the other way round in the device, the roll of tape cannot be inserted so far onto the parts 23, 24, 25 and 26 that the thickened parts 27 and 28 of the resilient lips 25 and 26 can grip behind the core 20. This means that the roll of tape is not held in place, which becomes clear to the person placing the roll of tape, who will immediately correct his mistake. Besides, in this incorrect position of the roll of tape, the tape runs crooked in the device, which is very obvious and must also be avoided, because in particular in the case of the paper tape this leads irrevocably to tearing of the tape. However, should the visibly incorrect position of the roll of tape escape the attention of the person, he or she will then find that the cover 3 will not close. This is achieved by the fact that the cover 3 is designed in such a way that it can be closed only if the roll of tape 10 is situated in its correct position. In this exemplary embodiment this is achieved by forming lugs 35 on the inside of the cover 3, which lugs lie next to the roll of tape 10 when the device

is closed.

As a result of the groove 21 disposed asymmetrically in the core 20, it is necessary to place the core 20 in the correct position in the tape winding machine when the tape is being wound onto the core 20.

It emerges clearly from the above description that by relatively simple means it can be made impossible to place the roll of tape incorrectly in the device. As a result of this improvement, the system is particularly suitable for intensive applications where the roll or the rolls of tape have to be changed often and quickly by persons who know little or nothing about the operation of such closure systems, such as in the retail trade or indus¬ try. It is also clear that the idea of the invention can equally be achieved in a way other than that described with reference to the drawings.