Cutting device of web for packing

Abstract: A cutting device of web for packing is provided, in which a web (1) is cut by means of an upper blade (7) and a lower blade (8). This web (1) is made cylindrical by joining both edges of the web into an independent cylindrical body (1′) of specified dimensions which becomes a container for packing. On the side of the blade body of the upper blade (7) or the lower blade (8) which opposes the sectional face of the cut cylindrical body (1′), a suction port (15) is provided which is connected to a suction device such as a blower (18) and is caused to open so as to suck in the air around the cut portion of the cylindrical body (1′).

Description: The present invention relates to an apparatus for cutting a cylindrical web for packing as defined in the preamble of claim 1. as for example known from JP-A-59 118 658. It has been a general practice to pack beverage such as milk, juice, and yogurt with laminated materials which mainly use paper as base material and include synthetic resin material or metallic foils according to purposes. In packing means which employ such laminated materials, both edges of continuous belt shaped laminated materials (hereinafter called web) are joined into a cylindrical shape as shown in figure 7. The cylindrical shape is cut into an independent cylindrical body of specified dimensions and formed to a packing body of beverage by means of sealing means and filling means. In an apparatus for cutting a cylindrical web for a packaging container this web is cut into an independent cylindrical body. In an apparatus for cutting a cylindrical web, usually the web of certain dimensions is sent out intermittently so that the web is cut by a cutting device comprising an upper blade and a lower blade. In order to perform accuarte feeding of web, as disclosed in the generic JP-A-59-118658 (1984), there has been a concept known according to which a notch is provided on a part of the web and upper and lower blade bodies are made freely oscillatable in the advancing direction of the web to cause the notch of the web to engage with the upper blade thereby accurately controlling the cutting position. From US-A-4 333 369 there is known an apparatus for dividing a fibrous mineral blanket comprising means for slitting the blanket into batts, a suctin chamber having one or more narrow openings adapted for contact with the side edges of the batts, and a vacuum pipe extending into the chamber for educting air and airborne particles from the chamber and the side edges of the batts. The vacuum pipe has its eduction opening position near the bottom of the chamber. This document neither relate to the field of packaging in general nor to the manufacturing of a packaging container by using a cylindrical web, which is however the application field of the present invention. However, in a conventional cutting apparatus, the dust such as paper powder is not removed which may possibly be generated when the web is cut with the upper blade and the lower blade. Hereby it is a premise that the web is cut by the upper blade and the lower blade which are maintained in perfect state. However, in case where the web made of paper as the base material, there is a possibility that paper dust is generated. There was no guarantee that such paper dust attached to a part, such as the inner surface of the cut cylindrical body, to be mixed into the content of the packing. Thus there is a demand for an apparatus for cutting a cylindrical web for packing, capable of removing fine dust such as paper powder which may possibly be generated during web cutting. In respect of a packing of beverage, the hygienic problem that foreign matters do not mix into the content of the packing is most important. The main object of the present invention is to provide an apparatus for cutting a cylindrical web for packing in which when the web for packing is cut, dust such as paper powder is removed by sucking the air around the cut portion of the cut cylindrical body so that dust attached or possibly attached to the cylindrical body can be removed. According to the present invention there is provided an apparatus for cutting a cylindrical web as set out in claim 1. So the apparatus for cutting a cylindrical web of the invention has effective means by which at least a part of the suction port is disposed at a position directly opposing the space in the cylinder which is formed by the elasticity of the cut cylindrical body itself or the air sucked in from the suction port is discharged to the atmosphere via a dust collector. Further, the blade body frame where the upper blade and lower blade are disposed is supported by means of a shaft so as to make the blade body frame oscillatable. By this embodiment it is possible to utilize the oscillation of the blade body frame for positioning the accurate cutting position of the web. In an apparatus for cutting a cylindrical web of the kind referred to above, the suction duct to be connected to the blower is fixed to the front of the blade body frame and the suction port and the suction duct is connected by a flexible tube. When the web is cut by the cutting action of the upper blade and the lower blade of the apparatus according to the invention, the cut cylinder body is positioned in front of the upper blade or the lower blade. At this time, if the air around the cut portion is sucked from the suction port provided on the side of the blade body, paper powder and other dust generated during cutting will be sucked in and removed. In an apparatus for cutting a cylindrical web, in which at least a part of the suction port is directly opposed to the space in the cylinder which is formed by the elasticity of the cut cylindrical body itself, the air passing through the space in the cylinder is sucked into the suction port. Consequently, not only the dust around the cutting face but also the dust that has entered inside the cylinder will be sucked into the suction port. According to the apparatus for cutting a cylindrical web for packing as described above, paper powder etc. which is possibly generated by the cutting action of the web can be removed and the possibility for even fine dust to mix inside the packing body of beverage can be reduced. By the preferred embodiment of the invention according to claim 2, it is obtained that the air to be sucked passes through inside the cylindrical body thereby enhancing the dust preventive effect inside the cylindrical body. In the preferred embodiment according to claim 3, there is no possibility for the sucked dust to be discharged into the air, that is, the contamination of the working environment is prevented and the dust does not attach to the web. In the preferred embodiment according to claim 4, free movement of the blade body for cutting the web can be allowed. Preferred embodiments of the apparatus for cutting a cylindrical web for packing according to the present invention will hereinafter be described with reference to the accompanying drawings: Fig. 1 is a front view of a partial notch of the whole of the cutting apparatus; Fig. 2 is a longitudinal side view of Fig. 1; Fig. 3 is an enlarged front view of the cutting blade portion showing the web after cutting; Fig. 4 is a longitudinal side view of Fig. 3; Fig. 5 and Fig. 6 are schematic front views showing the positional relationship between the cut cylindrical body and the suction ports provided on the side of the blade body; and Fig. 7 is a perspective view showing an example of the processing procedures of the web for packing. In the drawings 1 relates to a web, 1' to a cylindrical body, 5 to a shaft, 6 to a blade body frame, 7 to an upper blade, 8 to a lower blade, 9 to a guide lever, 10 to a lower blade supporting block, 11 to a cylinder, 15 to a suction port, 16 to a flexible tube, 17 to a suction duct, 18 to a blower, 19 to a dust collector, 20 to an elbow and 21 to a cylindrical space. Fig. 7 shows an embodiment of a web for packing, wherein the flat band-like web 1 is turned up from both sides, the edges thereof are joined and formed into a cylindrical shape. The web 1 which is formed into continuous cylindrical shape is cut at a specific position to get an independent cylindrical body 1' which is used for forming a container for packing. This web 1 is drawn with the line for bending shown by alternate long and two short dashes line and a notch 3 is provided at the specific cutting position. When the web 1 ist turned up from both sides thereof and formed to a cylindrical shape, the cylinder expands to some extent by the elasticity of the web itself and the dimension between the lines for bending on both sides and the dimension of the flat part to be turned up and joined are different so as to facilitate subsequent work. As shown in Fig. 5 and Fig. 6 the upper and lower blade bodies which form the cutting apparatus for the cylindrical web are supported by a shaft 5 with respect to the body frame 4 and mounted on the blade body frame 6 which is oscillatable in the advancing direction of the web 1. On this blade body frame 6 is fixed the upper blade 7 and the lower blade 8 which is associated to the upper blade 7 and is fixed to a lower blade supporting block 10 which is made slidable in vertical direction at the position concerned. In addition, by vertically moving and driving the lower blade supporting block 10 it is obtained that the web 1 is cut. The blade body frame 6 is osciallated into the advancing direction of the web 1 by a separate cylinder 12. The notch 3 of the web 1 and the upper blade 7 are caused to engage when moving the blade body frame 6 toward the front of the web advancing direction, so that the cylinder 11 is driven under such condition to cut the web 1 at the specified position as shown in Fig. 2 and Fig. 4. As can be understood from Fig. 3, on the side of the blade body of the upper blade 7 are opened two oblong suction ports 15, 15 at a position opposing to the cutting face of the cut cylindrical body 1'. These suction ports 15, 15 are connected to the suction duct 17 which is fixed at the front of the oscillating frame 6 by means of flexible tubes 16, 16 respectively. One end of the suction duct 17 is connected to the blower 18 which performs sucking action so as to suck the air from around the suction port 15. In the embodiment shown in Fig. 1, however, the air is passed through the bag filter type dust collector 19 so that dust such as paper powder which is sucked in together with the air is removed. Incidentally, this dust collector 19 may be of other type such as an electric dust collector or an inertia dust collector. In the embodiments of the apparatus for cutting a cylindrical web shown in the drawings, in order to permit smooth air flow and to prevent residue of dust, an elbow 20 is provided which is opened in the suction duct 17 in the direction of air flow. One end of this elbow 20 is caused to open outside of the tube through the tube wall of the suction duct. The other end of the flexible tube 16 whose one end is connected to the suction port is connected to this elbow 20. If, however, the present invention can be applied to the type of an cutting apparatus other than the type whose blade body frame 6 including the upper blade and lower blade oscillate, and if the upper blade or the blade on which the suction port is provided can be fixed, it is possible to connect the suction port and the suction duct by means of stationary piping without using flexible tube. If the suction port 15 which is caused to open on the side of the blade body of the upper blade or the lower blade, if the cutting face of the cylindrical body 1' is in a zone where dust is sucked in by suction (hereafter called the suction area), the number and position of such suction port are not limited. In the embodiment shown in Fig. 5, two suction ports 15, 15 which are opposed to both ends of the cutting face of the cylindrical body 1' are provided, so that the suction areas A, A expand all over the cutting face of the cylindrical body 1'. In contrast to the above, in the embodiment shown in Fig. 6, another suction port 15' is additionally provided on the intermediate portion of the suction ports 15, so that the entire sectional face of the cylindrical body 1' is covered by the suction areas A, A and A' of these suction ports. Incidentally, in the embodiments shown in both Fig. 5 and Fig. 6, a part or the whole of the suction ports 15, 15 and 15' is provided at a position opposing the direction to the space 21 in the cylinder which is formed by the elasticity of the cut cylindrical body 1' itself. The position of the suction port may be deviated either to above or below the cylindrical body 1' if the suction area of the suction port expands all over the sectional face of the cylindrical body 1'. However, in a cutting apparatus in which the suction port 15 is not opposed directly to the space 21 of the cylinder of the cylindrical body 1', there is a possibility that the air flow in the space 21 in the cylinder is disturbed and the dust preventive effect by suction becomes insufficient. In contrast to this cutting apparatus, in the cutting apparatus as shown in Fig. 5 and Fig. 6 wherein the suction ports 15, 15' are opposed directly to the space 21 in the cylinder, the cylindrical body 1' itself acts like a tunnel and thus the air to be sucked does not cause turbulent flow inside the cylindrical body 1' but flows as much in quantity as possible. Therefore, the removal and purificating action not only of the paper powder of the opposing sectional face but also the removal and purification action of the entire internal surface of the cylindrical body 1 are excellent.

Claims: An apparatus for cutting a cylindrical web, which is formed by joining both longitudinal side edges of a web (1), into an independent cut-off cylindrical body (1') of specific dimensions which becomes a packaging container, comprising cutting means having an upper blade (7) and a lower blade (8), characterized in that suction ports (15, 15) are provided in said upper blade (7) or lower blade (8) itself, open on a side of the blade body of the upper blade (7) or the lower blade (8) which opposes to a cut end of said cut-off cylindrical body (1') and at least partially disposed at a position which directly opposes to a space (21) formed in the cut-off cylindrical body (1'), wherein said suction ports (15) are connected to a suction device (18) such as a blower and face to the cut end of said cut-off cylindrical body (1') so as to remove dust such as paper powder generated during web cutting from around the cut end of said cut-off cylindrical body (1'). An apparatus for cutting a cylindrical web according to claim 1, characterized in that said space (21) in the cut-off cylindrical body (1') is formed by a resiliency of the cut-off cylindrical body (1') itself. An apparatus for cutting a cylindrical web according to claim 1 or 2, characterized in that the dust such as paper powder removed from the suction ports (15) by the suction device (18) such as a blower is discharged into the ambient air via a dust collector (19). An apparatus for cutting a cylindrical web according to anyone of the preceding claims, characterized in that the blade body frame (6) on which the upper blade (7) and the lower blade (8) are to be disposed is oscillatably supported by a shaft (5), that the cutting action of the web is accomplished by moving vertically by means of a cylinder (11) the lower blade supporting block (10) on which the lower blade (8) is fixed with respect to the upper blade (7) fixed on the blade body frame, that the suction port (15) is opened on the side of the blade body of the upper blade (7); that a suction duct (17) connected to the suction device (18) is stationary provided in front of the blade body frame (6), and that said suction duct (17) and said suction ports (15, 15) are connected by flexible tubes (16).

Inventors: OTSUKA YUZO, OTSUKA, YUZO
Applicants: TETRA PAK AB, AB TETRA PAK
Application year: 1989
Main classification: B26D7
IPC codes: B26D7, B31B1