This invention relates to a method of automatic cutting and removal of metal wire and/or -bands from objects, for instance pulp bales, by means of a machine, which are surrounded and are kept together by the wires/bands. The invention also relates to a machine for carrying out the method.

There are great problems connected with known technique when taking away the metal wires/-bands from the bales, because the wires/the bands are tightened extremely hard. Today this moment is often made manually, which is very risky because during the manual cutting off procedure, the wire ends may hit the person who performs the working moment and damage this one severely.

Attempts, however, have beea made to carry out the cutting off moment in a mechanical way. The equipment being at hand has been so complicated that it has not been used very much. This invention intends to solve the problems with known technique and offer a method and an apparatus for a secure and smooth procedure for cutting and removal of metal wires/-bands from objects. This has been made possible by the fact that the method and the apparatus have the characterizing features mentioned in the claims. Due to the invention the risk of injuries has been eliminated entirely during the cutting off moment. Furthermore, the invention makes possible a secure removal of the metal wires/-bands cut off.

A preferred embodiment of the invention shall be described more closely with reference to the accompanying drawings, where Fig. 1 shows a side view of the machine according to the invention, Fig. 2 shows a view of the machine taken along the line II-II of Fig. 1 , Fig. 3 shows a perspective view obliquely from the front of a cutting off device being an integral part of the machine, Fig. 4 shows a view obliquely from the back of the cutting off device according to Fig. 3, and Fig. 5 shows a cutting off means being an integral part of the cutting off device.

Referring to Figs. 1 , 2 is shown there the new machine. This one comprises a first cutting off device 1 , which is intended to be moved in a first direction on a frame 3 along a straight line by means of a first plunger cylinder 2. On the frame the object 4 (the pulp bale) is intended to be placed, on which the metal wires/-bands are intended to be cut off. In this connection the pulp bale 4 shall have such a position that the cutting off device 1 can

freely move at the side of the bale and along a side portion 5 of this one, in this case a long side.

The pulp bale 4 is, as has been mentioned, surrounded and kept together by a plurality, not shown metal wires/-bands. These ones preferably surround the bale in such a way that they extend essentially perpendicularly to the longitudinal direction of the bale 4. However, supplementary metal wires/ -bands may be used in such a way that these ones surround the bale in a direction which is essentially parallel with the longitudinal direction of the bale.

The cutting off device 1 comprises a first sensor means 6 (see Fig. 3), which is arranged on an elongated, essentially horizontal means 7 and which is intended to recognize metallic objecs. This sensor means is intended to give a signal to the plunger cylinder 2 to stop the movement of the cutting off device 1 parallel with the long side 5 of the bale 4 when a first metall wire/-band is discovered.

The cutting off device 1 is further in a pneumatic way movable against the bale 4 and the metal wire/-band in a second direction, which is essentially perpendicular to the first direction to a position where the horizontal means 7 goes into contact with the bale 4. The means 7 is fastened on a means 8, which is pivotal in the cutting off device 1 and which is pivotal about a horizontal axis 9 and can be pivoted in such a way that the horizonal means

7 with the sensor means 6 against the action of a spring means 10 can move backwards in relation to the cutting off device 1, seen in its other direction of movement. This means that if the cutting off device continues forwards in its second direction of movement, the means

8 will pivot about its horizontal axis 9, whereby the horizontal means 7 with the sensor means 6 moves backwards in relation to the cutting off device. In this connection the pivotal means 8 will influence a second sensor means 11 (see Fig. 4), which is intended to start the movement of the cutting off device 1 in its first direction.

The cutting off device 1 comprises a cutting means in the form of two steel cutters 12, 13 which are intended to go towards each other and catch hold of the metal wire/-band in order then to cut off the same. Each of the steel cutter 12, 13 is fastened on the fore portion of a plate 14, 15. The two plates 14, 15 are fastened on a common shaft 16 which is intended to be driven by an electric motor 17 and which is provided with left threads for the one plate and with right threads for the second plate. This means that when the shaft 16 rotates in the one direction, the steel cutters 12, 13 move towards each other and when the

shaft 16 rotates in the other direction, the steel cutters 12, 13 move from each other. As is apparent from Fig. 3 the device is so designed that the steel cutters 12, 13 can pass each other to an overlap position, i.e. the lower portion of the one steel cutter 12 is positioned right above the upper portion of the second steel cutter 13. In Fig. 5 the cutting means comprising the two steel cutters 12, 13 is shown more closely. These ones have such a design that they when moving towards each other shall be able to catch in the metal wire/-band in a secure way and cut off the same. For this reason the surfaces of the two steel cutters being directed towards each other have a pointed portion farthest out on the steel cutter. Furthermore, the mentioned surfaces of the steel cutters have recesses with such a design that a horizontal cross-section through these surfaces has a form which is like a V with the point of the V directed inwards. Due to that fact the pointed portion of the steel cutter can effectively .catch hold of the wire/the band surrounding the pulp bale and bring the wire/the band into the V-form-like recess, where the wire/the band is fixed for making possible a secure cutting off. The cutting off device 1 comprises two further sensor means 18, 19 (see Fig. 4). One of these sensor means is intended to give a signal to the device so that the shaft 16 stops rotating in the one direction and begins to rotate in the other direction, when the steel cutters 12, 13 have passed each other, whereas the other one of the sensor means gives a signal to the electric motor 17 to stop when the steel cutters 12, 13 have come to a certain distance from each other.

The cutting off device 1 comprises a second plunger cylinder 41 by means of which the movement of the cutting off device towards and from the bale can be performed. In the outer end portion of this plunger cylinder 41 is a further sensor means 42 arranged. The purpose of this sensor means is to give a signal to the cutting off device 1 to start again to move parallel with the pulp bale, when the plunger of the cylinder 41 has reached the outer end portion which means that the cutting off device has taken a maximum distance from the pulp bale.

In those cases when the parallelepipedic pulp bale 4 shown in the drawing also is provided with metal wires/-bands on its short sides, an additional, second cutting off device 20 is needed (see Fig. 1), which is identical and acts in the same way as the first one 1. The cutting off device 20 is positioned in front of the bale 4, seen in the movement direction R of the bale through the apparatus, and the first movement direction of the second cutting off

device 20 is accordingly essentially perpendicular to the first movement direction of the first cutting off device 1.

After the metal wires/-bands have been cut off and taken away, the pulp bale 4 shall be taken further away on a conveyer belt in the direction R and make room for a new pulp bale on which the wires/bands shall be cut off and removed. In order to make the further transport of the pulp bale 4 possible the second cutting off device 20 can be lifted up by means of two plunger cylinders 21, 22, each of which being arranged in a pillar 23, 24, which pillers are positioned at a distance from each other.

The machine according to the invention also comprises a device for collection and transportation away of the metal wires/ -bands cut off. In order that this at all shall be possible, the pulp bale 4 has to be lifted up from the frame. This is made by means of four pointed steel bars, of which two 25, 26 are shown in fig. 2.

The device for collection and transportation away of the wires/bands comprises a long arm 27, the one, inner end 28 of which being articulately suspended in a fixed means 29, and the other, outer end 30 of which being articulately suspended in a plunger cylinder 31 so that the end 30 can be lowered towards the pulp bale 4 or be raised from the same. A yoke 32 is displaceable there and back on the arm 27 in a pneumatic way. In the lower portion of this yoke 32 is an essentially square means 33 articulately fastened. A collection means 34-37 is arranged at each side of the square. Each collection means comprises a fixed hook 38 which projects out under the square means 33 and a movable hook 39 which also projects out under the means 33 and which in a pneumatic way can be displaced towards or from the fixed hook 38.

The machine according to the invention comprising the cutting off devices and the device for collection and transportation away of wires/bands cut off is preferably connected to a computer in which the different working moments which shall be performed by the machine is programmed in. Due to that fact all working moments can be made automatically.

The machine according to the invention functions in the following way:

A pulp bale 4 on which the wires/bands shall be cut off and removed comes in on a conveyer belt 40 and ends up on the frame 3 where the cutting off device(es) 1, 20 are positioned. The pointed steel bars 25, 26 lift up the bale 4 from the frame and are remained in the uplifted position so that the bale becomes fixed. That one or those cutting off devices

1, 20 being integral parts of the machine automatically searches and finds the first metal

wire band and cuts off the same. This is made in that way that the cutting off device moves towards the pulp bale 4 until the arm 7 with the first sensor means 6 goes into contact with the bale. The means 8 is pivoted about the axis 9, whereby the second sensor means 11 is influenced and gives a signal to the cutting off device to begin to move parallel with the bale. This movement goes on until the sensor means 6 recognizes a first metal wire/ -band. In this position the cutting off device is pressed against the pulp bale at the same time as the electric motor is given an impulse so that it begins to rotate the shaft 16 in the one direction, whereby the steel cutters 12, 13 move towards each other and overlap each other, whereby the metal wire/-band is cut off. This is recognized by a third sensor means 18 which stops the driving of the shaft 16 by the electric motor in the one direction and gives an impulse to the electric motor to rotate the shaft 16 in the other direction, whereby the steel cutters 12, 13 move from each other. At the same time the cutting off device begins to move away from the pulp bale. The driving of the shaft 16 by the electric motor in the other direction continues until the distance between the steel cutters 12, 13 is such that a forth sensor means 19 gets an impulse. In this position the sensor means 19 stops the electric motor. The movement away from the pulp bale of the cutting off device continues until the plunger of the cylinder 41 has reached the bottom. In this position an impulse is given to a fifth sensor means 42 which starts the movement of the cutting off device parallel with the pulp bale. This movement continues until the cutting off device has approximately come to the middle portion of the bale side, whereafter the cutting off device moves towards the bale side until the arm 7 with the sensor means 6 goes into contact with the bale. Then the same procedure as previously is repeated. Thus, the cutting off device automatically searches and finds the next metal wireΛband and cuts off also this one and this process continues until all metal wires/-bands are cut off. Thereafter the device for collection and transportation away of metal wires/-bands comes into function. In this position the arm 27 and the means 33 lie on the top of the pulp bale 4. The placing of the outer end 30 of the arm 27 with the means 33 on the pulp bale 4 is made approximately at the same time as the four steel bars 25, 26 lift up the pulp bale 4 from the frame. The movable hooks 39 of the collection means 34-37 are brought towards the fixed hooks 38 and clamp the wires/bands cut off against the hooks 38. Then the plunger cylinder 31 goes into function and lifts up the outer end 30 of the arm 27 so that the wires/bands go free from the bale 4. Thereafter the yoke 32 with the plate 33 is taken backwards on the arm 27 for transportation away of the wires/the bands. The pulp bale 4 without wires/bands is

taken further away on the conveyer belt and a new pulp bale is brought into the machine for cutting off and removing wires/bands.

The movements of the plunger cylinders 2, 31, 41 are preferably controlled in a pneumatic way. The invention is of course not limited to what has been shown and described here but can be modified within the scope of the following claims.