JPH0755466B2 - Sheet cutting mechanism - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cutting mechanism for a continuous sheet material (hereinafter, simply abbreviated as a sheet) such as a sheet, a film, and a folded cylindrical material. The present invention relates to a cutting mechanism capable of simultaneously cutting one cut end of a cutting part and the other cut end into different shapes.

(Prior Art) Conventionally, when a long tubular film is heat-sealed periodically to form a bottom portion and then cut in a region adjacent to the bottom sealing portion to manufacture a bag-like object, the bottom shape is horizontal. In the case of a straight line in the direction, the shape of the cut at the bottom and the shape of the cut at the opening of the next bag-like material were the same, and it was sufficient to cut using a straight cutting edge.

However, for example, when a bag for shrink-wrapping meat or processed meat thereof is manufactured, a round-bottom bag is required for the purpose of preventing appearance of the package after shrinking or preventing air residue at the corners. In such a case, arc-shaped heat sealing is performed and then cutting is performed using a cutting device having an arc-shaped blade edge adapted to the heat-sealing. In this case, the shape of the cut end of the opening of the next bag is a concave arc shape, which is difficult to handle when filling and heat-sealing the contents as it is, and the appearance of the package is unnatural. A method of re-cutting in a straight line in the process, or a method of first cutting in a straight line online and then using scissors or the like to cut into circles according to the seal part has been used.

(Problems to be Solved by the Invention) However, the conventional method as described above has a remarkably low productivity, requires extra manpower, and is extremely inefficient in the industry.

In order to eliminate such an inefficient situation, the present inventors initially carried out cutting by lowering and lowering at the same time in a state where the arcuate blade edge and the linear blade edge were in close contact, but cutting was performed in the vicinity where both blade edges were in close contact. It became incomplete and could not be separated.

(Means for Solving the Problem) As a result of intensive studies made by the present inventors in order to solve the above-mentioned problem, one of the two edges of the portion where the blade edges are in close contact (the portion where the cuts overlap) is missing. The present invention has been found to result in complete cutting, and has reached the present invention.

That is, the present invention is a device for simultaneously cutting a continuous sheet so that one cut end and the other cut end have different shapes, and a portion where both cut ends of the cutting edges of the cutting blades corresponding to both cut ends overlap. A pair of cutting edges with one cutting edge missing are closely arranged, and there is a pressing device composed of a pressing base and a pressing head for the sheet at the periphery of each cutting blade, and at least the cutting blade is lowered. The present invention relates to a sheet cutting mechanism having a mechanism capable of pressing and fixing a sheet between sheets.

In the present invention, the continuous sheet is, for example, a single layer, multiple layers, or a folded tube-like flat material used by cutting it into two or more pieces, and examples thereof include plastic, paper and other easily cut materials.

In the present invention, the cuts having different shapes are, for example, a combination in which the shape of one cut is a convex curve and the shape of the other cut is a straight line, and one shape and the other shape are convex curves and Examples include, but are not limited to, a combination with a concave curve having a smaller curvature, a combination of a convex curve and a convex curve, or a combination of a complicated curve and a complicated curve or straight line. .

The cutting blade used in the present invention is a combination of cutting blades having different shapes as described above, but in particular, two or more cutting blades are closely arranged, in which case one of the cutting edges is missing in a portion where the cutting edges overlap each other. It is what makes me. Further, it is preferable that the cutting edge used in the present invention has a serrated shape because of excellent sharpness.

Further, in the cutting mechanism of the present invention, a pressing device including a pressing head and a pressing base is arranged around the cutting blade to fix the sheet when cutting. The holding head is for fixing the sheet on the peripheral edge of the cutting blade, and the shape of the peripheral edge is preferably along the shape of the cutting edge. The holding head is adapted to be lowered and lowered at least during the cutting.

Further, the presser base is a fixed base for sandwiching and fixing the sheet between the presser head that is lowered and lowered.

In this cutting mechanism, if desired, a sheet chip removing device can be attached to the pressing device. As the removing device, the following various types can be adopted, but the removing device is not limited thereto.

(1) The inside of the presser base of the part that becomes the chip of the sheet is hollowed out to form a chip drop opening, and the core of the presser head is cut into the sheet, and after the presser head is lifted, it projects toward the hole of the chip drop opening. A protruding rod is provided as described above.

(2) The presser foot of the sheet part that becomes the chips of the sheet is hollowed out to serve as a chip outlet, and a pressurizing air outlet is provided at the core of the presser head to cut the sheet and then lift the presser head. A compressed air ejection device is provided so that the pressurized air is ejected from the outlet toward the hole of the chip dropping opening.

(3) The inside of the presser base of the sheet part that becomes the chips of the sheet is hollowed to form a chip suction port, and the other end of the chip suction port sucks the cut sheet piece when the pressing head is lifted after cutting the sheet. Attach a suction device that can

If desired, instead of the above-described chip removing method, a thin non-cutting portion that does not completely separate the sheet is provided on at least a part of the cutting blade that forms the cut edge of the cutting sheet piece that becomes the chips. It is also possible to provide a narrow width missing portion that remains.

In this case, chips are connected to the bag obtained by cutting, but can be easily torn off.

(Embodiment) The mechanism of the present invention is described below, in which the shape of one cut end is a convex curve,
The case of the cutting in which the other cut has a straight line will be described in detail by way of example, but the present invention is not limited to these examples, and one shape and the other shape are convex curves, respectively. A concave curve with a smaller curvature, a combination of a convex curve and a convex curve, or a combination of a complicated curve and a complicated curve or a straight line, where there is 1 part where the cuts of both shapes overlap Also applies to

Example 1 As shown in (1) of FIG. 1, an arc-shaped saw blade having a radius of curvature of 20 cm and a width of 30 cm, and an arcuate saw-tooth-shaped cutting blade with a central portion having a length of 5 cm was missing. , A straight blade with a length of 30 cm as shown in (2) and a central length of 5 cm
The cutting edge with the saw-toothed cutting edge lacking the edge part is in close contact with the central part of the arcuate edge (1), and the straight cutting edge (2) is perpendicular to the machine direction. Attached to the mounting device, and the adjacent part of the circular cutting edge on the center side of the circle,
A curved line separated by 5 mm from the cutting edge of the cutting blade is formed on each of the adjoining portion of the linear cutting blade that is not in close contact with the arc-shaped cutting blade and the portion sandwiched between (1) and (2). Holding heads (13), (14), (1
5), (16) and a pressing machine provided with a presser base (23) provided to receive the presser head, and a cutting machine provided with a presser device, the bottom shape of which is heat-sealed into a round bottom type with a radius of curvature of 19.5 cm ( 3
1) After feeding the continuous tubular sheet with a width of 20 cm so that the arcuate cutting blade (1) is located at a position 5 mm outside the round-bottom heat-sealing portion, the pressing heads (13), (1
4), (15), (16) are lowered and pressed to hold the sheet, and then the cutting blades (1) and (2) are lowered and lowered, the bag with the straight cut edge is cut off, and the bottom of the next bag is cut off. Had formed a nice round bottom.

The sheets of the presser heads (15) and (16) were separated from each other.

Example 2 The pressing head (25) of the pressing base (23) of the cutting machine of Example 1,
A through hole is provided in the lower part of (26) to form the chip drop openings (45) and (46), respectively, and the pressing heads (15) and (16).
Ejecting rods (35) and (36) having an outer diameter of 10 mm were provided in the core of the so as to penetrate through the holes of the chip dropping ports (45) and (46).

In the first embodiment, the pressing heads (13), (14), (15),
After pushing down (16) and then lowering the cutting blades (1) and (2) to separate the bag (32) having a round bottom, this protruding bar is pushed when the holding heads (15) and (16) are lifted again. (35) and (36) were pushed down so that they would pass through the chip drop openings (45) and (46).

The cut-off pieces in the lower part of the presser heads (15) and (16) of the tubular sheet passed through the chip outlets (45) and (46) and were removed from the cutting line.

Example 3 In Example 2, instead of the projecting rods (35) and (36), blown air outlets (55) and (56) were provided at the same position in the pressurized air having a diameter of 1 cm, and a compressed air source (pressure 2 kg / cm ² 50) via an air valve. Instead of pushing down the protruding rods (35) and (36) toward the chip outlets (45) and (46) in the second embodiment, at that time the air valve between the pressure source and the presser head (15) is opened. ,
The part of the sheet underneath (16) is separated from the chip opening (4
5), (46) and removed from the cutting line.

Example 4 A tubular sheet was cut in the same manner as in Example 1 except that both ends of the arcuate cutting blade (1) that was partially cut off in Example 1 were provided with blade tip missing portions each having a length of 0.5 mm. As a result, the bag was separated linearly, but the lower parts of the presser heads (15) and (16) were hung from the round bottom of the next bag through a thin uncut part. If you pull this part by hand while holding this bag, it will be easily separated,
The part (52) was a round-bottom bag similar to that in Example 1.

(Operation / Effect) As described above, according to the mechanism of the present invention, continuous sheet-like materials can be cut at the same time so as to have cuts of different shapes, so that a free-form bag-like material can be efficiently manufactured, Further, in the case where the chip removing device is provided, the chips are not mixed in the bag-shaped material.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of the cutting mechanism used in the first embodiment. FIG. 2 is a conceptual diagram showing a cross section taken along the line AA ′ in FIG. FIG. 3 is a conceptual diagram showing a cross section taken along the line BB ′ of FIG. 1 of the cutting mechanism provided with the chip protruding bar used in the second embodiment. FIG. 4 is a conceptual view showing a cross section taken along the line BB ′ of FIG. 1 of the cutting mechanism for removing the chips used in Example 3 with compressed air.

Claims (5)

[Claims] 1. A device for simultaneously cutting a continuous sheet-like material (hereinafter, simply referred to as a sheet) so that one cut end and the other cut end have different shapes, and both cut ends are supported. A pair of cutting edges with one cutting edge missing is closely arranged at the part where both cutting edges of the cutting blades overlap, and a pressing device consisting of a pressing base and a pressing head for the sheet is provided around each cutting blade. And a sheet cutting mechanism characterized by having a mechanism capable of pressing and fixing the sheet at least while the cutting blade is being lowered. 2. The inside of the presser base of the portion which becomes the chips of the sheet is hollowed out to form a chip drop opening, and the core of the presser head is cut into the sheet, and after the presser head is lifted, it goes to the hole of the chip drop opening. The sheet cutting mechanism according to claim 1, wherein a protruding bar is provided so as to be protruded. 3. A pressurizing head is lifted after cutting a sheet-like object by piercing the inside of a presser base of a part which becomes a chip of a sheet to form a chip outlet, and providing a pressurizing air outlet at the core of the presser head. The sheet cutting mechanism according to claim 1, further comprising a compressed air ejecting device that ejects pressurized air from the blowout port toward the hole of the chip dropping port after being blown. 4. A chip suction port formed by hollowing out the inside of a presser base at a portion which becomes a chip of a sheet, and sucking a cut sheet piece at the other end of the chip suction port when the pressing head is lifted after cutting the sheet. A sheet cutting mechanism according to claim 1, further comprising a suction device capable of cutting. 5. A cut portion having a narrow width is provided in at least a part of a cutting blade forming a cut portion of a portion of the sheet, which is a chip, so that a thin non-cut portion that does not completely separate the sheet remains. A sheet cutting mechanism according to claim 1.