CUTTING TOOL FOR STEEL BANDS

TECHNICAL FIELD:

The present invention relates to a tool for cutting an object, comprising at least a first and a second cutting member each of which comprising at least one edge, wherein the edges of the cutting members cooperate during cutting.

BACKGROUND OF THE INVENTION:

The invention is intended for cutting metal bands of the type which is used for packaging different kinds of packages. To this end, it is common to use metal bands with a thickness of approximately 0,5-1 mm and a width of approximately 10-32 mm, which are tightened around the package in question. A metal band of this kind is often under very high tension, and during cutting there is a risk that the band flies up, which in some cases may inflict injuries .

In order to overcome this problem there is previously known a cutting tool which functions according to the principle that the metal band is first bent, during which it is held firmly by the tool, and thereafter cut off. However, the metal band will be tensioned more tightly during the bending, causing even greater tensions to be generated in the metal band. When the latter is severed, the tensions will in fact be equalized slightly, but when the tool is thereafter released, there is however still a high tension in the band, which may cause it to fly up and cause damage.

CONFIRMATION COPY

Another drawback with this previously known tool is that the bending of the metal band itself demands a large force. This means that the handles of the tool must be long, which in turn makes the tool large and cumbersome.

SUMMARY OF THE INVENTION:

It is thus a primary object of the present invention to provide a tool which solves the above-mentioned problem of holding a metal band in a secure manner when it is cut.

This object is solved by means of a device of the above- mentioned kind, which is characterized in that at least one of the cutting members comprises a friction element which is so arranged that the object is clamped between the friction element and the other cutting member during cutting.

Due to the fact that the metal band, by means of the friction element, is held firmly during cutting, there is no risk that the band flies apart and causes damage. Furthermore, due to the fact that the cutting with the tool according to the invention is non-deforming, there is a relatively low need for power during cutting, which means that the tool can be made small and handy, without any need for long handles.

According to a particular embodiment of the invention, the tool may comprise a handle which is connected to the cutting members in such a way that a heavy gear reduction is obtained, which provides a large cutting force during cutting.

According to a further embodiment of the invention, the cutting members may be folded into the handle, which contributes to making the tool small and handy.

BRIEF DESCRIPTION OF THE DRAWINGS:

The invention will now be described in greater detail with reference to the annexed drawings, in which

Fig. 1 is an assembly drawing of the elements forming part of the invention,

Fig. 2 shows, in a lateral view, one step during assem¬ bly of the tool according to the invention,

Fig. 3 shows a further step during assembly of the tool,

Fig. 4 shows the complete tool in a lateral view, just before a metal band is to be cut off,

Fig. 5 shows the tool during the cutting,

Fig. 6 shows the metal band after a metal band has been cut off,

Fig. 7 shows the tool in its folded state,

Fig. 8 is a lateral view of an alternative embodiment of the invention,

Fig. 9 shows an alternative embodiment of the invention which comprises an exchangeable edge, and

Fig. 10 is a lateral view of a further embodiment of the invention.

PREFERRED EMBODIMENTS:

Fig. 1 shows the main parts of a tool according to the present invention. The tool comprises an essentially U- shaped handle 1, a first cutting member 2 and a second cutting member 3. The handle 1 is made of plastic, steel,

aluminium or some other suitable material, and its size is chosen for allowing gripping with one hand.

The handle 1 comprises two legs 4, 5. At the end section of each of the legs 4, 5 there are mounted two shafts 6, 7. The shafts 6, 7 which are preferably manufactured from steel are, due to reasons which will be apparent later, pivotably mounted in the respective leg 4, 5, i.e. they may rotate freely around their respective centre axis. The shafts 6, 7 are arranged essentially parallel in relation to each other.

According to the preferred embodiment, the two cutting members 2, 3, which are made of injection-moulded alumi- niu , alternatively by forged and machined steel, are of similar dimensions. The description below therefore only applies to the first cutting member 2, and it is to be understood that the second cutting member 3 is shaped in an essentially identical manner.

The cutting member 2 comprises a knife edge 8 which extends along a certain distance in the longitudinal direction of the centre axis of the cutting member 2. The knife edge 8 is formed by the edge of a curve-shaped section 9, which is raised in relation to a plane section 10. The front end section 11 of the cutting member 2 is essentially wedge- shaped, making it possible to insert the tool under the metal band to be cut, which will be apparent in greater detail below. The cutting member 2 is also provided with a friction element 12 which suitably is an essentially cone- shaped block of rubber or some other material with high friction. The friction element 12 is arranged on the plane surface 10 and has a height which is slightly less than the height of the curve-shaped section 9.

Furthermore, the cutting member 2 comprises an essentially cylindrically shaped section 13 which extends from the side edge of the cutting member 2 and along half the width of the cutting member 2. On the other side of the cutting member 2 , i.e. on the opposite side edge of the cutting member 2, there extends a recess 14 which is shaped essentially as a half cylinder.

The recess 14 of the first cutting member 2 is shaped so that it fits against a cylindrical section 13 ' of the second cutting member 3. In a corresponding way, the cylindrical section 13 of the first cutting member 2 is shaped so that it fits into a corresponding recess of the second cutting member 3. Each of the cylindrical sections 13, 13' comprise a cylindrical shaft hole 15, 15', which holes are intended to accomodate a shaft pin 16.

When the complete tool is to be assembled, the two cutting members 2, 3 are first fitted together so that the cylin- drical sections 13, 13' are matched with the corresponding recesses 14. Thereafter, the shaft pin 16 is inserted through the two shaft holes 15, 15'. In this way, the cutting members 2, 3 will become rotatably mounted and moveable in relation to each other around a common axis of rotation 17. The shaft pin 16 may preferably be provided with a (not shown) clip which is arranged in a groove at the middle of the shaft pin 16 in order to fix the shaft pin 16 between the cutting members 2, 3. The orifices of the shaft holes 15, 15', which are directed towards each other, may include recesses in which the clip may be fitted.

The rear section of the two cutting members 2, 3, respec¬ tively, is formed with a recess 18, 18' which essentially has the form of a half oval and which extends across the respective cutting members 2, 3. When the cutting members

2, 3 have been assembled together, these recesses 18, 18' form a duct with an essentially oval cross-section. The function of this duct will be described below.

The cutting members 2, 3 may be maintained together by means of a tube spring 19, which is pushed onto the rear sections of the cutting members 2, 3 during assembly of the tool. The tube spring 19 is provided with two longitudinal edge sections 20, 21 which cooperate with notches 22, 22' on the respective cutting members 2, 3.

As illustrated in Fig. 2, the complete tool is assembled by first fitting the cutting members 2, 3 together and there¬ after inserting the shaft pin 16 through the shaft holes 15, 15'. Thereafter, the cutting members 2, 3 are pushed together towards their closed position (i.e. the knife edges are pushed towards each other) . In this manner, an opening 24 is formed at the rear end sections 23 of the cutting members 2, 3. The cutting members 2, 3 may then be mounted on the handle 1 by bringing them towards the shafts 6, 7 of the handle 1, in a direction which is indicated by the arrow 25. Thereafter, the tube spring 19 may be pushed into place, as shown in Fig. 3. In this way, the edges 20, 21 of the tube spring 19 will snap into the notches 22, 22' of the cutting members 2, 3, respectively. By means of the tube spring 19, the cutting members are kept in place on the handle 1. The tube spring 19 also affects the cutting members 2, 3 so that their respective edges 8 are forced away from each other, i.e. so that the cutting members 2, 3, are forced towards their open position.

The function of the tool will now be described with reference to Figs. 4 to 6. In Fig. 4, the tool is shown in its open position, wherein the handle 1 (which is shown with a dashed line) is placed essentially perpendicular to the londitudinal direction of the cutting members 2, 3. The

shafts 6, 7 are arranged in the handle 1 along a line which, seen from the side, essentially coincides with the londitudinal direction of the cutting members 2, 3. The duct 26 which, in accordance with the above-mentioned, is formed in the rear sections of the cutting members 2, 3 accomodates the two shafts 6, 7. The tube spring 19 will affect the cutting members 2, 3 so that their rear sections 23, 23', respectively, strive towards each other and so that the shafts 6, 7 are in contact with the walls in the duct 26. As is apparent from Fig. 4, the respective cutting member 2, 3 are formed so that the duct 26 comprises two grooves 27, 27', which extend along the duct 26 across the two cutting members 2, 3, respectively. The grooves 27, 27' serve to define a stopping position for the shafts 6, 7, in a manner which will become clearer in the following.

According to that shown in Fig. 4, the tool may be intro¬ duced under a metal band 28 by means of the wedge-formed front section 11 of the first cutting member 2. Thereafter, the metal band 28 is placed in a position level with the friction elements (of which only the friction element of the first cutting member 2 is shown in Fig. 4).

In Fig. 5, the tool is shown in a position where cutting of the metal band 28 has commenced. In this regard, the metal band 28 (which is represented by a dashed line in Fig. 5) has been placed level with the two friction elements, and the handle 1 has been turned manually approximately 45° counterclockwise. The turning of the handle 1 forces its shafts 6, 7 to be moved, while at the same time they exert a force against the inner walls of the duct 26. As a concequence of the fact that the duct 26 has an oval cross- section, the shafts 6, 7 will force the cutting members 2, 3 to rotate towards one another, around the axis which is defined by the shaft pin 16 (i.e. the axis of rotation 17 in Fig. 1) .

In this position, the friction element 12 acts against the metal band 28 so that the latter is clamped between the friction element 12 and the curve-shaped surface 9 ' of the second cutting member 3. In a corresponding way, the second cutting member's 3 friction element (which is not shown in Fig. 4) will hold the metal band 28. The tool will cut and clamp the metal band 28 in one single movement. When the metal band 28 has been severed, the tensions therein will be released due to the fact that the friction element 12 is slightly elastic and non-rigid. The metal band 28 will be held firmly between the cutting members 2, 3 for as long as they are pressed together.

Since the shafts 6, 7 are pivotably arranged in the legs of the handle 1, they will roll along the inner walls of the duct 26. This means that merely an insignificant frictional force will be generated between the shafts 6, 7 and the inner walls of the duct 26, which contributes to reducing the force which is necessary to cut the metal band 28.

As a concequence of the symmetrical arrangement of the shafts 6, 7 and the duct 26, and due to the fact that the handle 1 is U-shaped with room for the cutting members 2, 3, it is to be understood that the handle 1 may be swung both counterclockwise and clockwise during cutting of the metal band 28. An operator of the tool may thus sever the metal band by folding the handle in a direction either towards or away from himself.

Fig. 6 shows the tool according to the invention in a position just after the metal band has been severed. The two shafts 6, 7 have been pressed against the walls of the duct 26 so that the cutting members 6, 7 are brought to their closed position. In this regard, the shafts 6, 7 will cooperate with the grooves 27, 27' of the duct 26, which

thus define a "stopping position" for the handle 1 in relation to the cutting members 2, 3.

The handle 1 may, as has been mentioned earlier, also be swung clockwise until the longitudinal axis of the handle 1 essentially coincides with the longitudinal axis of the cutting members 2, 3. This position is shown in Fig. 7. It is to be understood that the length of the legs 4, 5 is chosen so that a space is formed in the handle 1 with room for the cutting members 2, 3. In this regard, the function of the grooves (27, 27', see Figs. 4 to 6), which cooperate with the shafts 6, 7, is to hold the cutting members 2, 3 in the folded position, i.e. when they have been folded between the legs 4, 5 of the handle 1. In this manner, it is achieved that the cutting members 2, 3, to some extent, are held in a locked position inside the legs 4, 5 of the handle 1. It is to be understood that the locking action of the grooves 27, 27' (see Figs. 4 to 6) depends on their width and depth. Due to the fact that the tool is foldable, the front edges of the cutting members 2, 3 may be made relatively sharp (which is often necessary in order to introduce the tool under the metal band) , since these parts are not exposed when the tool is folded. This is an advantage regarding the safety during handling of the tool.

In Fig. 8 there is shown in a simplified form an alter¬ native embodiment of the cutting members 2, 3, in which the cross-section of the duct 26 has a shape which implies that different cutting forces be required depending whether the handle is folded clockwise or counterclockwise. If, by the influence of the (not shown) handle, the shafts 6, 7 are turned counterclockwise, the cutting force will be lower than if the shafts 6,7 are turned clockwise. Also, the length of the cut will be affected by a shape according to Fig. 8. In addition, other shapes of the cross-section of the duct 26 are of course possible.

In Fig. 9 there is shown a cutting member 2 which is provided with an exchangeable edge section 29. This may, for example, be screwed to the cutting member 2. The edge section 29 itself may preferably be manufactured from steel, and the rest of the curve-shaped surface 9 from some other material, for example some lighter material such as plastic. In this manner, the tool can be made light. In this manner, different kinds of exchangeable edge sections may be utilized for an otherwise identical tool. The different edge sections may be matched to the dimensions and the material properties of different kinds of metal bands.

In Fig. 10, there is shown an alternative embodiment of a tool according to the invention, which tool comprises a first cutting member 30 and a second cutting member 31. The cutting members 30, 31 are pivotably arranged in relation to one another due to the fact that the first cutting member 30 comprises a first shaft 32 which is rotatably arranged in the second cutting member 31. The second cutting member 31 comprises a protruding section 33 on which there is arranged a cam member 34 which comprises a cam surface 35. The cam member 34 is pivotably suspended on a second shaft 36, and may be affected by means of an operating lever 37 which is arranged in a fixed manner in the cam member 34. If the operating lever 37 is turned clockwise, i.e. the direction which is indicated by the arrow 38, the cam member 34 will push the first cutting member 30 against the second cutting member 31. The cutting movement itself of the tool, i.e. the cooperation between the edges of the cutting members (of which only the edge 39 of the first cutting member 30 is shown in Fig. 10) is carried out in the same manner as in the embodiment which has been described above. At least one of the cutting members 30, 31 comprises a friction element 40, which serves to hold a metal band 41 during cutting of it.

The invention is not limited to the above-mentioned embodiments, but may be varied within the scope of the appended claims. For example, the friction element 12 may be manufactured from a number of different materials and shapes. The friction element 12 of, for example, the first cutting member 2 may also cooperate with a bowl-shaped, recessed section in the curve-shaped section 9' of the second cutting member 3. According to a further embodiment, the friction element 12 may be formed by a spring-loaded pin which is arranged in the plane section 10 and which presses against the metal band 28 during cutting. Also, the plane sections of the respective cutting members 2, 3 may be shaped as a frictional surface, or may alternatively be provided with some kind of coating which exerts a high frictional force against the metal band during severing.

Also, the shaft pin 16 (see Fig. 1) may be provided with means for fastening the cutting members 2, 3 to one another, i.e. so that the cutting members 2, 3 are arranged at a certain predetermined distance from each other. To this end, there may also be provided spacing washers or the like in connection with the shaft pin 16.

Furthermore, the cutting members 2 , 3 do not have to be identical, it being important only that they may be arranged on the common axis of rotation 17 and that their respective knife edges 8 are arranged along a common line of the cutting members 2, 3.

Also, the shafts 6, 7 do not have to be arranged along a line which, seen from the side, is perpendicular to the longitudinal direction of the handle (cf. figure 4), but the shafts 6, 7 may be displaced in relation to this line. In this manner, the cutting motion of the tool may be modified.

According to a further embodiment of the invention, the duct 26 may be designed with a plurality of grooves 27, 27', in order to define several stopping positions. Furthermore, other cross-sections of the duct 26 than those mentioned above are possible.

Furthermore, the tool may be provided with some kind of safety catch which prevents the cutting members 2, 3 from being folded out from their position between the legs 4, 5 of the handle 1 when the tool is not in use. Also, the front section of the handle 1 may be provided with some kind of protruding knife or the like.

It is to be noted that the knife edge 8 may be perpendi- cular (as seen from the front), or may alternatively be shaped obliquely, so that the knife edge 8 can cut into the metal band 28 more easily.

Finally, it is to be noted that the tool may be used for cutting objects other than metal bands.