The object of the present invention is a hand tool for cutting a resilient web material, such as a paper web, along a guide member, particularly a joining tape, held onto the material, the tool comprising a frame with a handle, at least one guiding edge, and a cutting member fastened at a predetermined position in relation to the guiding edge. The tool according to the invention is in particular intended for preparing a joint in a paper web or some other web such as cardboard, plastic film, or foil, in which case the web to be joined is cut by means of the tool at a point adjacent to the joining tape.

In making paper rolls or other rolls of a predetermined size, it is necessary to make joints in the web in order to bring the length of the web to the predetermined value. The joints are in general made by using a double-sided tape. The tape is first glued to the first of the webs to be joined, from which the excess part of the web is then torn off along the tape. Next, the protective strip which has covered the tape is removed from the tape, and the second web is glued to the tape. Again, the excess part of the web is torn off.

Both of the above-mentioned tearing steps may, owing to uneven tearing, reveal some of the self-adhesive tape, which, when the reeling is continued, will adhere to the web layers surrounding the joint. At a further handling stage, when such a roll is unwound, the adhesion causes a break which may be highly detrimental.

The adhesion can be prevented by using a one-sided tape as a covering tape at the torn point. However, this causes

additional work and cost. The covering tape will make the joint considerably thicker than the web itself and will cause difficulties in the further handling of the web. A torn area which is uncovered may also yield detrimental dust and lint during further handling, for example during printing.

In general it is not possible to cut webs easily at a point adjacent to the joint, without damaging the remaining web. The web cannot be cut at a point very far from the joint, since in general long tails should not be left around the joint.

The methods currently used are unreliable in terms of the quality of the joint, and they often result in the entire web being rejected at printing machines or other machines in which the web is further handled, owing to difficulties of running the web through.

The tool according to the invention provides a crucial improvement with respect to the disadvantages described above.

The tool according to the invention is characterized in that there is a plate-like element attached by one of its ends to the frame of the tool in such a way that between, this end and one side of the frame there is left a slot, open at one end, the plate-like element having been fitted so that it can be pushed under the material to be cut, the material extending through the slot, that the guiding edge is located next to the slot and is parallel to the slot, and that the cutting member is fastened to the frame at a distance from the open beginning of the slot.

The guide edge may consist of an edge of the plate-like element, the edge at the same time delimiting the slot.

In one preferred embodiment the tool also comprises a second guiding edge, which is parallel to the first guiding edge and is located in the bottom of the frame, laterally at a distance from the cutting member. Thus, when the tool is used for cutting, for example, a paper web along a join¬ ing tape attached to the web, the distance between the guiding edges is approximately the same as the width of the joining tape.

It can be considered that the most important advantage of the invention is the fact that both of the web ends in the joint will be neat, the joining tape, glue, etc., will always remain hidden and cannot cause the joint to adhere to web parts to which it is not supposed to adhere, and the run reliability of the joints in further refining processes of the web is significantly improved. It is also not insig¬ nificant that, by means of the tool according to the inven¬ tion, the web can be cut at exactly the desired distance from the joint edge so that the glue joining the web cannot spurt out of the joint in a further process which may have such side effects. The need for using a covering tape is eliminated and the making of a good joint is facilitated.

The invention is described below in detail, with reference to the accompanying drawings, in which

Figure 1 depicts a perspective view of a tool according to the invention,

Figure 2 depicts the tool according to Figure 1, as seen from below.

Figure 3 depicts an altered embodiment of the tool, as seen from the end, and

Figures.4-8 depict the making of a joint by using the tool according to the invention.

Figure 1 thus depicts the tool according to the invention -

in a simplified form. The tool comprises a metal or plastic frame 1, to which there belongs, as an integral part, a protrusion 2 and, as an integral or separate part, a handle 3. A plate-like element 4 has been fastened at one of its ends to the protrusion 2 so that a slot 16, open at one end, is formed between the edge 4a of the plate and the frame 1.

To the bottom of the frame 1 there is further fastened a strip 5 the edge 5a of which constitutes a guiding edge parallel to the edge 4a. This edge 5a is also visible at the point which has been cut open in Figure 1.

At the slot 16 there is a part 6 which is either integral with the frame or fastened to the frame, and further a cutting blade 7 fastened to the part 6. The tip of the blade 7 extends somewhat into the depression 8 in the plate element 4. Finally there is a notch 9 in the lower surface of the protrusion 2, so that above the element 4 there is formed an open space somewhat inwards from the edge 4a.

As is shown in Figure 2, the plate-like element 4 and the strip 5 are fastened by means of countersunk screws to the protrusion 2 respectively to the frame 1. By making the fastening holes in the element 4 and the strip 5 slot-like in the transverse direction it is, when so desired, pos¬ sible to adjust the location of the edges 4a respectively 5a in relation to the cutting blade 7. It is, of course, also possible to use elements 4, 5 of different widths for varying the location of the guiding edges.

Instead of the edge 4a of the element 4, for example the edge 5b of a narrow strip secured to the frame 1, facing away from the slot 16, can also serve as a guiding edge, as shown in Figure 3.

Figures 4-8 show how the tool described above can be used for joining two paper webs to each other.

In accordance with Figure 4, a transverse joining tape 13, with a protective strip on top of it, has been attached on top of the paper web 12 to be extended, close to its uneven end. The tool is passed from the edge of the web onto the tape so that the plate-like element 4 is pushed under the paper web end 12a to be cut off. After this, the tool is passed across the web in the direction indicated by the arrow so that the tool is guided by mediation of the guid¬ ing edge 5a by the left side of the tape 13 and its protec¬ tive strip.

The web 12 can also be cut from the other side by turning its free end back on top of the web, as is shown in Figure 5. In this case the tape is left under the web 12 to be cut, and the tool is guided by the guiding edge 4a, which is guided along the right-side edge of the joining tape.

If the paper web 12 is soft and lacks body, a ruler 14, attached to the joining tape 13, can also be used as an aid in the cutting, as is shown in Figures 6 and 7. The ruler, which is of a material easily detachable from the tape, is first attached to the joining tape 13 and thereafter the end of the web 12 is turned back on top of the web in the manner shown in Figure 7. After this, the end 12a of the web is cut off in the same manner as in Figure 4.

When the end of the web 12 has first been cut straight across at a point adjacent to the edge of the joining tape 13 in the manner indicated in Figures 4-7, the second web 15 is attached to it as is shown in Figure 8. In other words, when the protective strip of the joining tape 13 has been removed, the web 15, uneven at its end, is placed as a continuation of the web 12 and is pressed against the tape

13. After this, the end of the web 15a is again cut off so that the tool is guided by means of the guiding edge 4a along the right-hand side edge of the tape.

Returning to Figure 1, the blade 7 can, of course, be lo¬ cated at the edge 4a or, as shown in an exaggerated manner in Figure 1, at some distance from the edge towards the element. In this case the cut paper edge will, of course, go somewhat beyond the edge of the tape. This will happen also in the case of Figure 3, in which the blade 7 is in¬ evitably located off to the side in relation to the guiding edge 5b. It is also evident that, if the fastening of the element 4 is such that the position 4a of the edge can be somewhat adjusted, the depression 8 must be respectively widened so that the blade 7 will not hit the element 4. It is, however, advantageous that the blade is always above the element 4, because then the element 4 prevents the paper layer underneath from being damaged. The depression 8 may, of course, also be, for example, a notch made in the edge 4a, the notch not extending all the way to the bottom of the element 4.

It is evident that the embodiment described above can be varied in many ways within the idea of the invention. The plate-like element 4 can, of course, be any part, relative¬ ly rigid in the lateral direction, which is capable of forming a longitudinal guiding edge 4a. Otherwise the ele¬ ment can be of any shape, as long as it is moderately thin and smooth at the open end of the slot 16, so that it can be easily pushed under the web to be cut off. It is also evident that in a simple embodiment the element may consti¬ tute one part with the frame 1 and 2.

The fastening of the blade 7 is, of course, implemented in such a way that the blade can easily be replaced. In addi¬ tion, the blade may be made adjustable in both the lateral

and the vertical direction.