EP0712372B1 - Cutting device for a foil dispenser - Google Patents

Abstract

A cutting device for a foil dispenser for aluminium, transparent, paper foils and the like has a cutting mechanism capable of moving over the whole width of the foil and having a blade that cuts in both directions of displacement. The blade extends with play through a cutting slot that opens into a guiding tract. This part of the blade is embedded in a sliding shoe capable of moving along the guiding track. The cutting mechanism has only one blade (4) fixed in relation to an actuating handle (2, 24, 44) for all types of foils. The cutting edges (11, 20) of the sides of the blade, which extend into a cutting slot (6), are symmetrically arranged in relation to a central link plate (5) or bridge (22, 43) and form an acute angle alpha with a longitudinal edge of the cutting slot (6); alpha equals less than 25 DEG , preferably about 15 DEG . In addition, the cutting device has holding down means arranged at the cutting spot in the cutting plane that cooperate with the blade (4) and that press the foil on the outer wall of the housing onto the part of the blade that is located outside of the housing (7) of the foil dispenser.

Description

The invention relates to a cutting device of a foil dispenser for aluminum, transparent, paper foils or the like with a cutting mechanism that can be moved over the entire width of the foil, cuts in both directions of movement, and is designed with guide means that has a knife that is fixed in relation to an actuating handle with a center on both sides a tab connected to a sliding guide or a bridge part, with blades extending into a cutting slot, and with the cutting point in the cutting plane of the knife cooperating hold-down means which place the film on the outside wall of the housing on the outside of the housing (7) knife part .

In a cutting device of this type known from DE-U-92 16 733.0, two separating rollers with a knife in between are arranged in a cutting mechanism. The separation rollers engage with a cutting edge in the cutting slot and can thus cut through aluminum foil, which is not possible with the knife alone. Other types of film such as transparent or paper films are stretched between the cutting rollers and then cut from the knife side.

This cutting system has proven itself in practice. However, due to the different types of knives, these cutting devices are structurally very complex, since a separate release agent must be present for the different types of film.

The invention is based on the object of designing a cutting device of the type mentioned at the outset, which can cut through films made from a wide variety of materials and which is structurally simple, preferably with few individual parts.

This object is achieved in that the cutting unit for all types of film has only one knife, the knife sides of which form a flat angle α with respect to a longitudinal edge of the cutting slot, α being less than 25 °, preferably approximately 15 °, and the cutting edges a gate and then insert the boundary edges of the cut of the foil, in particular the aluminum foil, into the cutting slot over the entire cutting distance.

Surprisingly, films of all types can only be cut with a knife. Only the correspondingly flat angle α ensures that the foil placed by the holding-down means on the outer wall of the housing is inserted by the cutting edges with their boundary edges into the cutting slot and is cut through by the cutting edge. This results in good cutting behavior of the cutting device when cutting aluminum, transparent and paper foils with one and the same knife.

While it was still assumed in the prior art that only transparent and paper foils, but not aluminum foils, can be severed with a fixed knife, the invention creates a single knife with which these foils can be severed. Since only a knife is used, the cutting device can be made very short and structurally simple.

A further reduction in the overall length of the cutting device results from the arrangement according to the invention of a tab or a bridge part which is arranged between the two knife components which cut in different directions. The tab or the bridge part protrude far into the Cutting slot into it and can be fixed there on a slide shoe, through which the guidance of the cutting device is realized. Without the use of such a tab or of such a bridge part, the length of the cutting device would have to be approximately twice as large if the deep penetration of the knife tip of a pointed knife into the cutting slot would then be necessary. As a result, the overall length of the housing would also have to be extended by this value.

The flat angle α prevents, above all when cutting aluminum, that a bead-like accumulation of aluminum foil pushed onto one another, which cannot be severed, forms in front of a knife that may be too steep.

In an advantageous embodiment of the invention, the hold-down means are recessed in the vicinity of the cutting slot and in the cutting direction, thereby improving the operation of the knife. Likewise, those hold-down devices that do not consist of pairs of rollers are made of slidable or easily slidable plastic material, such as Nylon, provided.

The knife is made of hardened steel and has a hardness of at least 50 to 60 Rockwell grades, making the knife almost wear-free.

The cutting edges of the knife separate the respective film in the transition area between the cutting edges and the cutting slot. If the cutting edge has lost some sharpness in this area after many hours of operation of the cutting device, as practice shows, the aluminum foils can still be cut perfectly. The transparent films move from the area lost in sharpness into the cutting slot and are gripped and cut there by an unused cutting part.

Cutting transparent film is wear-free for the knife.

The interaction of the knife, the hold-down means and the edges of the cutting slot ensure that the film to be cut is inserted into the cutting slot, i.e. that the parts of the film lying against the cutting slot are pulled a little into the cutting slot and are slightly bent there. This behavior of the film in the arrangement of the cutting device according to the invention significantly improves the cutting process.

The single knife of the cutting device can be formed in one piece. However, there is also the option of making the knife out of several components, e.g. composed of three components. These knife parts are either placed in a shell-like grip part consisting of two parts, which can be connected to a film hinge, on molded-on pins and recesses. By folding the handle parts together, these knife parts get a firm fit. They can be injected into a holding chassis for assembly with a handle part.

A further reduction in the size of the cutting device can be achieved in that the tab or the bridge part is fixed in a slide shoe which has a conicity which widens perpendicularly to the plane of the knife with an increasing distance from the knife and which is guided in the cutting slot on corresponding conical counter surfaces, in order to ensure good cutting behavior, the side of the slide shoe facing the knife should lie behind the housing surfaces for the purpose of contacting the film. This guidance of the sliding block in the cutting slot makes additional guide surfaces on the side of the housing facing away from the knife superfluous, and it is also possible to assemble such a sliding block guided in a conical guide by simply inserting it. The dimensions of the cutting device can thereby be reduced significantly.

Further features of the invention emerge from the subclaims.

Fig. 1

eine Schneidvorrichtung und den zugeordneten Teil des Gehäuses eines Folienspenders im Grundriß,

Fig. 2

eine Ansicht in Richtung des Pfeiles II,

Fig. 3

das in der Fig. 1 aufgezeigte Messer mit zugeordnetem, kufenförmig ausgebildetem Niederhalter,

Fig. 4

eine Ansicht in Richtung des Pfeiles IV in Fig. 3,

Fig. 5

das Messer der Schneidvorrichtung im Grundriß mit aufgesetzten Rollenpaaren, die als Niederhalter für die zu schneidende Folie wirken,

Fig. 6

eine Ansicht in Richtung des Pfeiles VI in Fig. 5,

Fig. 7

ein einstückiges Messer im Grundriß und

Fig. 8

im Schnitt ein als Niederhalter wirkendes Rollenpaar, zwischen dem das Messer eingespannt ist,

Fig. 9

ein weiteres Ausführungsbeispiel der Schneidvorrichtung im Schnitt, mit einem aus drei Teilen sich zusammensetzenden Messer,

Fig. 10

eine Ansicht in Richtung des Pfeiles X in Fig. 9,

Fig. 11

die Schneidvorrichtung nach der Fig. 9 im Grundriß, und ungeschnitten,

Fig. 12

ein weiteres Ausführungsbeispiel einer Schneidvorrichtung im Horizontalschnitt mit Rollenpaaren als Niederhalter und

Fig. 13

einen Schnitt nach der Linie XIII-XIII in Fig. 12.

Fig. 14

eine weitere Ausführungsform der Schneidvorrichtung im Längsschnitt,

Fig. 15

einen Schnitt nach der Linie XV-XV in in Fig. 14,

Fig. 16

eine mit zwei Rollenpaaren als Niederhalter ausgestattete Schneidvorrichtung im Längsschnitt,

Fig. 17

einen Schnitt nach der Linie XVII-XVII in Fig. 16,

Fig. 18

eine Schneidvorrichtung im Längsschnitt, die als Niederhaltemittel endlose Weichgummibänder aufweist,

Fig. 19

einen Schnitt nach der Linie XIX-XIX in Fig. 18,

Fig. 20

einen Schneidvorrichtung im Längsschnitt, die als Niederhaltemittel Blattfederbügel aufweist,

Fig. 21

einen Schnitt nach der Linie XXI-XXI in Fig. 20,

Fig. 22

eine Schneidvorrichtung mit einem aus zwei Teilen bestehenden Griffteil, wobei die Teile über ein Filmscharnier miteinander verbunden sind, mit aufgeklapptem Griffteil,

Fig. 23

die Ausführungsform nach der Fig. 22 mit einem zusammengeklappten Griffteil und

Fig. 24

eine Ansicht in Richtung des Pfeiles XXIV in Fig. 23.

Fig. 25

ein Schneidwerk mit einem innerhalb des Schneidschlitzes geführten Gleitschuh, prinzipieller Aufbau in Vergrößerung dargestellt

Fig. 26

Seitenansicht des Schneidwerks der Figur 25

Embodiments of the cutting device are shown in the drawings and are described below. Show it:

Fig. 1

a cutting device and the associated part of the housing of a film dispenser in plan,

Fig. 2

a view in the direction of arrow II,

Fig. 3

1 with an associated, skid-shaped hold-down device,

Fig. 4

3 shows a view in the direction of arrow IV in FIG. 3,

Fig. 5

the knife of the cutting device in plan with attached roller pairs, which act as hold-downs for the film to be cut,

Fig. 6

5 shows a view in the direction of arrow VI in FIG. 5,

Fig. 7

a one-piece knife in plan and

Fig. 8

on average a pair of rollers acting as hold-downs, between which the knife is clamped,

Fig. 9

another embodiment of the cutting device in section, with a knife composed of three parts,

Fig. 10

9 shows a view in the direction of arrow X in FIG. 9,

Fig. 11

9 in plan, and uncut,

Fig. 12

a further embodiment of a cutting device in horizontal section with pairs of rollers as hold-down and

Fig. 13

a section along the line XIII-XIII in Fig. 12.

Fig. 14

another embodiment of the cutting device in longitudinal section,

Fig. 15

14 shows a section along the line XV-XV in in FIG. 14,

Fig. 16

a longitudinal section of a cutting device equipped with two pairs of rollers as hold-down devices,

Fig. 17

a section along the line XVII-XVII in Fig. 16,

Fig. 18

a cutting device in longitudinal section, which has endless soft rubber bands as hold-down means,

Fig. 19

18 shows a section along the line XIX-XIX in FIG. 18,

Fig. 20

a cutting device in longitudinal section, which has leaf spring clips as hold-down means,

Fig. 21

a section along the line XXI-XXI in Fig. 20,

Fig. 22

a cutting device with a handle part consisting of two parts, the parts being connected to one another via a film hinge, with the handle part opened,

Fig. 23

the embodiment of FIG. 22 with a folded handle and

Fig. 24

a view in the direction of arrow XXIV in Fig. 23.

Fig. 25

a cutting unit with a sliding shoe guided inside the cutting slot, basic construction shown in enlargement

Fig. 26

Side view of the cutting unit of FIG. 25

The cutting mechanism 1 shown in FIGS. 1 and 2 has an actuating handle 2 in which the fastening part 3 of a knife 4 is embedded. This fastening part of the knife 4 is rectangular in the embodiment shown. In one piece with the fastening part 3 of the knife 4 is a centrally arranged tab 5 which is rectangular in plan in the exemplary embodiment shown, which extends through a cutting slot 6 of the housing 7 of the film dispenser and is fixed in a sliding block 8. This slide shoe 8 is movably mounted parallel to the cutting slot 6 in a guide channel 9 which is delimited by webs 10 which extend parallel to the cutting slot 6. The cutting unit 1 receives its guidance in the guide channel 9, while the knife 4 passes through the cutting slot 6 with play on both sides.

The knife 4 has a cutting edge 11 on each side facing the possible direction of movement. These cutting edges 11, which start from the fastening part 3, extend over the entire depth of the cutting slot 6 and end at the fastening tab 5.

The cutting edges 11 form an angle α with respect to the longitudinal plane of the cutting slot 6, which is kept so flat that the cutting edges 11 insert the boundary edges of the cut of the film into the cutting slot 6 already during the first cut and then over the entire cutting distance.

The angle α must be less than 20 °. To achieve good cutting conditions and a small overall length of the knife 4 and thus the cutting unit 1, an angle α is selected which is approximately 15 °.

The knife 4 is made of hardened steel and preferably has a hardness of at least 50 to 60 Rockwell degrees.

The cutting unit 1 is equipped with hold-down means 12, 14, which are preferably provided on the top and bottom of the knife 4 and place the film on the housing wall during the movement of the cutting unit 1. If they do not consist of pairs of rollers, these hold-down means 12, 14 are made of slidable and non-slip plastic material, e.g. Made of nylon, which shows very good sliding properties on the matt side of the aluminum foil.

In the exemplary embodiment according to FIGS. 1 and 2 and in the illustration in FIGS. 3 and 4, the hold-down means are designed as runners 12 which, in the plan according to FIG. 1, stand out from the cutting slot 6 at the free end regions 13 and in the illustrated embodiment have an arcuate course in these end regions 13.

From Fig. 2 it follows that the knife 4 passes through this skid-shaped hold-down device 12, 13 in the middle.

However, as shown in FIGS. 5 and 6, two pairs of rollers 14 which are spaced apart in the cutting direction and which hold the knife 4 between them can also be provided as hold-down means.

8 shows a pair of rollers 14 designed as a hold-down device, in which a roller 15 is equipped with a hollow pin 16 which projects beyond the roller width and which can be inserted into a corresponding receptacle 17 of a second roller 18. In this embodiment too, the knife 4 is arranged between two pairs of rollers 15, 16.

9, 10 and 11 show a cutting unit 19 which is equipped with a knife which consists of several parts. The knife has two parts 21 equipped with cutting edges 20 and a bridge part 22 between the slide shoe 23 and the actuating handle 24. The parts 21 are enclosed with the exception of the cutting edges 20 by the actuating handle 24, while the bridge part 22 is embedded on the one hand in the actuating handle 24 and on the other hand in the slide shoe 23 or is fastened as parts - as already described.

12 and 13 show an exemplary embodiment of a cutting device in which two pairs of rollers 14 spaced apart from one another are provided as hold-down means, which are largely encapsulated by the actuating handle 25 in that they are rotatably mounted in receptacles 26 of the actuating handle 25. The axle journals 27, 28 of the rollers 14 are received by a bearing recess 29 of the actuating handle 25.

It can be seen from FIG. 13 that the rollers 14 forming the hold-down device are provided with chamfers 30 adjacent to the knife 4 arranged between the rollers of a pair of rollers 14, so that the roller parts adjacent to the knife 4 do not impair the cutting operation of the knife 4.

If the hold-down means, as shown in FIGS. 1, 2, 3, 4, are designed as runners 12 or strips, these hold-down means are recessed in the vicinity of the cutting slot 6 and in the cutting direction, so that the cutting operation is not impaired by these hold-down means and any splash burr is behind.

In the embodiment according to FIGS. 10 and 11, the hold-down devices are designed as strips 31, 32 which are integrated in the actuating handle 24 or form parts of the actuating handle. The strips 32 are opposite to the one running parallel to the cutting slot 6 Bar 31 angled and form an acute angle with the cutting slot 6.

In FIG. 2, the outer housing surface 33 assigned to the cutting device projects outwards relative to the other outer housing surface 34. This simplifies the cutting of the film insofar as the film, which is subjected to tensile stress by hand, is stretched in the area of the cutting device via the housing projection, which is delimited on the outside by surface 33. This simplifies handling of the film and cutting. Likewise, the front front in the area of the cutting slot 6 can be bulbous or crowned.

The cutting device according to FIGS. 14 and 15 has an actuating handle 24 which at the same time forms the hold-down means. It can be seen from FIG. 15 that the actuating handle 24 and thus the hold-down means in the vicinity of the knife 4 have a groove-like recess 34 on each knife side.

The chamfers 30 provided on the roller pairs 14 of the embodiment according to FIGS. 16 and 17 act in the same way in the vicinity of the knife 4.

Due to this exposure of the knife 4 in the immediate vicinity of the cutting slot 6, parts of the hold-down means cannot negatively influence the cutting operation.

In the cutting device according to FIGS. 18 and 19, endless soft rubber bands 35 are provided as hold-down means, which run around rollers 36 designed as rims, the rollers 36 being provided with pins 37 and being rotatably mounted in the actuating handle 1.

19 that an endless soft rubber band 35 is arranged on each side of the knife 4. The cutting device also works well if an endless soft rubber band 35 is provided on only one knife side.

In the exemplary embodiment according to FIGS. 20 and 21, the actuating handles 38 are equipped with leaf spring clips 39, which act as hold-down means and can be formed in an arc shape from plastic. These leaf spring clips 39 are designed and arranged so that, in operation, the spring bears slightly under pressure on the outer surface of the housing of the film dispenser or on the film, so that the clips 39 sweep over the film with uniform pressure when cutting.

22 to 24, the knife consists of the parts 40 and 41, which are provided with cutting edges 42 and a bridge part 43, through which the handle 44 is connected to the sliding shoe 45. The bridge part 43 has the same thickness as the knife parts 41 and 42, is made of the same material and is hardened. This bridge part 43 is T-shaped and has a crossbar 46 on which the knife parts 40 and 41 bear in a form-fitting manner, and are thus supported.

The actuating handle 44 consists of two shell parts 47 and 48, which are preferably articulated to one another via a film hinge 49. The shell part 47 has pins 50, 51 which are inserted through bores 52 in the knife parts 40 and 41 when the handle parts 47 and 48 are folded together.

From the representations in FIGS. 22, 23 and 24 it follows that this cutting device can have either pairs of rollers or skids as hold-down means.

25 and 26, the basic structure of a further advantageous embodiment of a cutting device according to the invention is shown, in which a tab 5 or a bridge part 22, 43 of a knife 4 cutting on both sides is fixed in a sliding block 8, which is guided within the cutting slot 6 and is held in this cutting slot 6 by a widening taper pointing away from the knife 4. The knife 4 is as described above Embodiments between rollers 14 fixed in a handle part 1 and engages with the component formed here as a tab 5 in the cutting slot 6. The cutting slot 6 is formed at least in the area of the cutting slot 6 in a thick-walled housing part which is formed from the two lamellar housing parts 54 and 55. The cutting slot 6 has a conicity widening on the side facing away from the knife 4, which is preferably formed in the range of a few degrees of angle, preferably approximately 10 °. The slide shoe 8, on which the knife 4 can be fixed here with its tab 5, has a rectified and equally large conicity, so that the slide shoe 8 is guided in the cutting slot 6 in such a way that it faces the knife after insertion conical outer surface is a little behind the outer housing surface 33 on which the film 53 rests during the cutting process. This creates sufficient space for cutting the film 53 with the knife 4, into which the cutters 11 arranged on both sides penetrate. The assembly of slide shoe 8, knife 4, rollers 14 and handle 1 takes place in such a way that the cutting slot 6 is briefly widened by slightly pushing apart the lamella-like housing components 54 and 55, so that the preassembled unit comprising slide shoe 8, knife 4 and handle 1 ' can be inserted into the cutting slot with the sliding block 8. Due to the conical fit of the slide shoe 8 and the cutting slot 6, after the lamellae 54 and 55 are released, it is slidably slidably clamped in the two sides of the lamellae 54 and 55 forming the cutting slot 6. The dimensional arrangement of the slide shoe 8, knife 4 and rollers 14 allows the handle 1 'to be easily moved on the housing outer surface 33, the film 53 being able to be cut. This design, with a sliding shoe 8 guided in the cutting slot 6, permits a considerably more compact design of the cutting device and makes the construction of specially required guide strips on the back of the associated housing wall 54 and 55 superfluous the length of the sliding block 8, which essentially corresponds to the length of the knife 4, ensures a uniform and precise guidance of the cutting device.

Claims (14)

1. A cutting device for a foil dispenser for aluminium-, transparent- or paper foils or the like, having a cutting tool (1) which can move over the entire width of the foil, which cuts in both directions, and which is equipped with guidance means, which cutting tool comprises a cutter (4) which is fixed with respect to an operating handle (2, 24, 25, 44) and which has cutting edges (11, 20, 42) which are disposed on both sides of a central tab (5) or bridge part (22, 43) attached to a sliding guide (8, 23, 45), and cutting faces of which extend into a cutting slot (6), and having holding-down means (12, 31, 14, 35, 39), which cooperate with the cut location in the cutting plane of the cutter (4) and which lay the foil on the housing external wall, and which are provided on the cutter part situated outside the housing (7), wherein the cutter faces form an angle α in relation to a longitudinal edge of the cutting slot (6), characterised in that the cutting tool (1) solely comprises one cutter (4) for cutting all types of foil, the cutter faces of which form the shallow angle α which is less than 25°, preferably about 15°, and the cutting edges (11, 20) insert a first cut and then insert the boundary edges of the cut in the foil, particularly in aluminium foil, into the cutting slot over the entire extent of the cut.
2. A cutting device according to claim 1,
   characterised in that
   the holding-down means are constructed as runners (12, 13) or as guide rails (31, 32) and that the end regions of the holding-down means are outwardly raised from the cutting plane, wherein the guide rails (31, 32) can also preferably be produced in one piece with an operating handle (24).
3. A cutting device according to claim 1,
   characterised in that
   two pairs of rollers (14) are provided in each case as the holding-down means, between which the cutter (4) is disposed.
4. A cutting device according to any one of the preceding claims,
   characterised in that
   the holding-down means are recessed in the manner of a channel in the vicinity of the cutter (4) and of the cutting slot (6), and are recessed in the cutting direction.
5. A cutting device according to claim 1,
   characterised in that
   the holding-down means are constructed as arcuate, resilient leaf spring bows (39).
6. A cutting device according to claim 1,
   characterised in that
   the holding-down means are constructed as endless soft rubber belts (35) which circulate around rollers (36) fashioned as wheel rims.
7. A cutting device according to any one of claims 1 to 6,
   characterised in that
   the cutters (4, 21) consist of hardened steel with a Rockwell hardness of 50 to 60 degrees.
8. A cutting device according to any one of claims 1 to 7,
   characterised in that
   the cutter (4) is of one-piece construction and has a centrally disposed, perforated tab (5) for its fixation in the sliding shoe (8).
9. A cutting device according to claim 1,
   characterised in that
   the cutter (4) consists of a plurality of parts, preferably of two parts (21) provided with cutting edges (20) and of the bridge part (22) between the sliding shoe (23) and the operating handle (24).
10. A cutting device according to claim 9,
    characterised in that
    the bridge part (43) is of T-shaped construction and comprises a crosspiece (46), and the cutter parts (40, 41) are seated with a positive fit against the bridge part (43).
11. A cutting device according to any one of the preceding claims,
    characterised in that
    the tab (5) or the bridge part (22, 43) is fixed in a sliding shoe (8, 23) which has a taper which is perpendicular to the plane of the cutter (4) and which widens with increasing distance from the cutter (4), which sliding shoe is guided on tapered counterfaces in the cutting slot (6) and the side of which which faces the cutter (4) is set back in the cutting slot (6) in relation to the housing faces (33) for the support of the foil.
12. A cutting device according to claim 11,
    characterised in that
    the operating handle (44) consists of two shell parts (47, 48) which are joined to each other by a film hinge (49).
13. A cutting device according to any one of the preceding claims,
    characterised in that
    the associated housing outer face (33) protrudes outwards in relation to the remaining housing outer face (34).
14. A cutting device according to any one of the preceding claims,
    characterised in that
    an obtuse angle β is provided between the cutting edges and the adjacent contour of the tab (5) or of the bridge part.

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