GB2267075A

GB2267075A - Guide for binding material

Info

Publication number: GB2267075A
Application number: GB9310133A
Authority: GB
Inventors: Charles Fischer
Original assignee: Strapex Holding AG
Current assignee: Strapex Holding AG
Priority date: 1992-05-19
Filing date: 1993-05-17
Publication date: 1993-11-24
Also published as: ITMI930977A1; DE4316907A1; IT1264439B1; JPH0632308A; GB9310133D0; TW226355B; ITMI930977A0; FR2691428B1; FR2691428A1

Abstract

Band guiding apparatus for wrapping a band around a package includes, at the inside of a supporting frame (16, 17), two U-shaped flaps (21, 22) urged by means of an elastomeric element (23) against an abutment (18) whereby upon a pulling effect acting on the band located in a channel (26), the flaps yield sideways and release the band such that it can place itself around and contact a package. The elastomeric element (23) may comprise a series of sections and is disposed between the flaps (21, 22) and against the outer circumference of the abutment (18). The abutment may comprise several sections mounted on the frame (16, 17) by supporting bolts (19) and spacers, the spacers being exchangeable to adjust the height of the channel (26). Pressurised air may be supplied to inflate a member (32) acting on the outer surface of legs of the flaps (21, 22). <IMAGE>

Description

2267075 A BAND GUIDING APPARATUS FOR A WRAPPING BAND LOOPING MACHINE

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

The present invention relates to a band guiding apparatus for a machine for looping a wrapping band around an article, having a band looping arc structure, a ty supporting frame for said band looping arc structure including two respective parallel multiple-part Ushaped guiding flaps having inner and outer legs projecting respectively towards each other, which flaps are held by a resilient force against a central abutment structure extending also in a loop, which flaps each have an inner end with the inner ends forming together with said abutment a channel for receipt of a band, the flaps being adapted to be opened at their inner ends by a spreading motion due to a pulling effect acting on the band.

DESCRIPTION OF THE PRIOR ART

Wrapping band looping machines by which a plastics material band can be wrapped and looped around packages of all kinds and sizes have been known for a long tp time. Such wrapping band looping machines are designed in a compact manner. Apart from the mechanical operating structures and the electrical and electronical control structures, the machines also include a processing table and a band channel extending upwards from the surface of the table, namely the band guide or the so- called band looping are structure, in which the band is led around a package to be wrapped placed on the table, and is thereafter pulled out of the band guide and is tightly placed onto the packages and welded together.

The object of the band guide is to guide a band which is shot or pushed thereinto at a distance around the package and to hold the band in this position up to a signal for fusing the band.

2.

For the fusing, the band must finally be released by the band guide alone, the entire circumference of the band guide, generally by a continuous release operation, such that the placing onto and engagement of the package and the fusing by welding of the band can be made.

Substantially two types of band guiding apparatuses are known:

In one of the types, the band guide consists of a looping are having a laterally open groove. At a given time, the arc shaped band guide with the band placed thereinto is then moved sideways, as by a lever arm mechanism operating automatically, due to the tension of the band, after having been opened at one location, such that the band moves relative thereto through the lateral slot to the outside and can be brou-ht into direct engagement with the package by a pulling action.

In the second type, corresponding to the design as initially mentioned, the band is also guided in an arc shaped looping band guide around the package, specifically in a 0 channel which is formed by two flaps which are biassed towards each other by a spring force, until the channel is opened by a pulling action on the band resulting in the two flaps pivoting away from each other at the inner side, i.e. directly opposite the package, such that the band releases itself progressively out of the channel and places itself around the package.

The band channel of this known design cannot be adjusted regarding its dimensions. The pressure springs, acting from the side and pressing the flaps against each other, have additionally and unintended effect that if the channel opens at one side only, i.e. if only one flap pivots laterally against the force of the spring, the other flap is loaded correspondingly higher due to the increased pressure of the spring acting now thereonto.

This can lead to malfunctions, specifically to a twisting of the band.

SUMMARY OF THE INVENTION

It is, therefore, an object of the invention to provide a band guide design corresponding to the second of the kinds mentioned above which is of a simple structure 0 and does not have above-mentioned drawbacks.

PATiN9 53 0. 1 3.

The invention provides a band guiding apparatus for a machine for looping a wrapping band around an article, which comprises an clastomeric material inserted at least in sections into the space between the outer legs of the flaps and the outer circumference of the loop-shaped abutment structure and adapted to produce a resilient force in the space between the outer legs of the flaps, which preferably multi-sectioned looping abutment is mounted by mounting members to the supporting frame for the band looping arc structure.

In this extremely simple design, if a flap gets opened by the band, the other flap becomes loose, i.e. not loaded or unloaded (due to the deformed elastomeric material).

Preferably, there is provided a band guiding apparatus, in which the mounting members include screw bolts and spacers, which spacers are exchangeable in order to adjust the height of the channel for receipt of the band. The closing force of the flaps can be adjusted by selecting shorter or longer members (hose portions) of an elastomeric material, andlor by employing softer or harder rubber, andlor by using shorter or longer is spacers. It has been shown that the function of the band guide is secured already by using or inserting only a few relatively short members of an elastomeric material, which among other things also renders the mounting of the supporting members (spacers, threaded bolts) easy.

The design, assembly and production of the band guide (profile members) are extremely simple.

Due to the fact that the generation of the closure forces on the band guide is caused by an elastomeric material and possibly additional shock-absorbing inserts, the looping machine will operate quite quietly.

0 BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described further, by way of example, with reference to the accompanying drawings, wherein:

0 Fig. 1 illustrates a transportable wrapping band looping machine, on a schematic basis; PAnN9530.1 4.

Figs. 2 and 3 are schematic cross-sections of band looping arc structures in accordance with the prior art;

Figs. 4 and 4a are cross-sections taken along the lines B-B and C-C, respectively in Fig. 5 of a band guide structured in accordance with the invention; Fig. 5 is a longitudinal section through such a band guide in a corner region of the support; and Fig. 5a is a cross-section along line A-A of Fig. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Fig. 1 of the drawings illustrates purely schematically a movable wrapping band looping machine having a working table 1, and a band feed 2 from a coil 3 to a band looping arc 4. The commodity or package (not illustrated) around which the band is to be looped is placed in a passage 5 of the band looping arc 4. The operation and working is procedures of such machines are generally known and, therefore, are not explained in detail: Basically, a band 3' on the supply coil 3 is shot (pushed) into the band looping arc 4 until the loop of the band is closed at the location where later the welding will be made. The free end is held arrested. Upon a control signal, the band 3' is pulled back by the supply mechanism and is thereby pulled continuously out of the channel for receipt of the band of the band looping arc 4 and placed around the package, whereupon it is welded and cut off. As a rule, a next section of band has then already been shot in.

Figs. 2 and 3 illustrate a cross-section, purely schematically, of the hitherto generally used band guides in the so-called looping are 4.

In the design according to Fig. 2, the band 6 is held in a slot 7 of a looping guide which is open at its side. The guide can be moved at least at one location sideways away by a (not illustrated) mechanism, such that the band is released and continuously leaves the slot due to an application of a pulling force and is placed onto the package.

This known system is complicated, specifically regarding the production of the arcing sections proper (corners) of the band guide.

The design according to Fig. 3 forms the basis of the present invention: A central looping abutment 9 provides a support for a band looping arc (not illustrated). Two flaps PAnN9530.1 5.

10, 11 are held on this central abutment 9 by bolts 12 and pressure springs 13, 1Y, whereby a channel 14 for receipt of the band is formed at the inner end thereof. By a pulling action on the band the flaps 10, 11 are moved away from each other against the pressure of the springs 13, 13', and the band is released successively in the direction of the package, direction of the arrow, and places itself around the package.

A drawback of this design is that the channel for the band cannot be adjusted.

Further, if only one of the flaps 10, 11 opens upon a pulling action at the band 15, the other one will be loaded corresponding to the increasing spring pressure accordingly higher, which can influence negatively the functioning properties.

Figs. 4 and 4a illustrate cross-sections through a looping arc structured in accordance with the invention, which includes a stationary support frame 16, 17 made of profiled metal members. A looping central abutment 18 located inside of the as such known support frame 16, 17 and made also of profiled members is mounted via bolts 19 and spacers 20 at a desired distance from the support 16, 17. Two U- shaped flaps 21, 22 made of metal or a plastics material are disposed between the abutment 18 and parts of the support, which flaps lie against the flanks of the abutment 18 due to the influence of an elastomeric member 23.

At the inside end, a channel 26 for receipt of the band (not illustrated) is formed between the abutment 18 and inner legs 24, 25 projecting towards each other. Already c at a slight increase of the tension of the band when the band is pulled back the flaps 21, 22 pivot to the side and outwards (see maximum end position shown by broken lines) and let the band exit towards the inside through the opening 26' in the support 16 such that it will contact the package.

By a selecting of suitable distance spacers 20 the height of the channel 26 for the band can be adjusted. The elastomeric member 23 can be selected as a massive profile or as a portion of a hose. The closing force can be influenced by a corresponding selection of the hardness of the elastomeric member (also by a selection of the geometry of the member andlor the distance of the abutment 18).

Shock absorbing members 27, 28 may be located in the flanges of the abutment 18 in order to dampen the recoil of the flaps 21, 22.

PAnN9,530 1 6.

The elastomeric element 23 can be formed by a plurality of individual portions (then the spacers 20 can be led through two respective adjacent portions). For each rectilinear portion and each curved portion of the looping arc, one to two relatively short elastomeric elements suffice for ensuring functioning.

In the above-described design the elastomeric element 23 is pressed together, in the event that only one flap 21, 22 opens, in such a manner that the other flap becomes loose or is released from its loading, which increases considerably the functioning properties.

An additional member 32 like the member 23 may be provided in the space 29 between the supporting frame 17 and the outer legs 30, 31 of the flaps, which member 32 may be expandable by pressurized air (e.g. from a pressurized air hose or possibly -also hydraulically) such as to open both flaps 21, 22 as soon as the member 32 has been inflated by means of the pressurized air supply.

Fig. 5 illustrates on a somewhat reduced scale a corner section of the band is looping arc. It discloses that the curves at the corners can also be equipped with flaps without a too high expenditure, which leads to an optimal guiding of the band. Fig. Sa illustrates a cross-section along the line A-A through this corner area.

Due to the inventive design, it is possible without any big expenditure to set the apparatus up for arbitrary dimensions of the band looping arc. It suffices to cut corresponding profiled members for the support frame, abutment and flaps to the corresponding lengths, to assemble these parts and to insert the elastomeric elements and members at the desired locations.

While there are shown and described presently preferred embodiments of the invention, it is to be understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims.

P.An\9530.1 7.

Claims

1. A band guiding apparatus for a machine adapted to loop a wrapping band around a commodity, having a band looping arc structure, a support frame for said band looping arc structure including two respective parallel multiple-part U- shaped guiding flaps having inner and outer legs projecting respectively towards each other, which flaps are held by a resilient force against a central abutment structure extending also in a loop and which flaps each have an inner end with the inner ends forming together with said abutment a channel for receipt of a band, the flaps being adapted to be opened at their inner ends by a spreading motion due to a pulling effect acting on the band, the apparatus further comprising an elastomeric material inserted at least in sections into the space between the legs of the flaps and the outer circumference of the loop shaped abutment structure and adapted to produce a resilient force in the space between said legs of the flaps.

is

2. A band guiding apparatus as claimed in claim 1, in which the central abutment is multiple-sectioned and is mounted by mounting members to said support frame for said band looping arc structure.

3. A band guiding apparatus as claimed in claim 2, in which said mounting t> members include screw bolts and spacers, which spacers are exchangeable in order to adjust the height of the channel for receipt of the band.

4. A band guiding apparatus as claimed in claim 1, 2 or 3, wherein said resilient force is produced by sections, specifically sections of hoses, of an elastomeric material, which sections are exchangeable.

5. A band guiding apparatus as claimed in claim 4, in which said insertable clastomeric sections are of various lengths and/or consist of various materials.

cl PA T. N cl 5 -, 0. 1 8.

6. A band guiding apparatus as claimed in claim 1, 2, 3, 4 or 5, in which said central abutment structure includes side walls and in which shock absorbing members e.g. rubber inserts are located in said side walls.

7. A band guiding apparatus as claimed in claims 1, 2, 3, 4, 5 or 6 in which said support frame for the band looping arc structure, said central abutment structure and said 0 flaps are formed of profiled members made of metal or of plastics materials.

8. A band guiding apparatus as claimed in claim 1, 2, 3, 4, 5, 6 or 7, in which hydraulically or pneumatically expandable members for opening the flaps and for controlling a closing force are arranged in the space between the outer legs of the flaps.

9. A band guiding apparatus substantially as herein particularly described with reference to and as illustrated in Figs. 4 and 5 of the accompanying drawings.

P.AnN9530.1