JP3385510B2 - Film cutting device and cutting method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film and sheet (hereinafter, simply referred to as a film) cutting device and a film cutting method using the device, and more particularly, to a cut end having good cutting performance. The present invention relates to the above-mentioned cutting device and the cutting method in which is linear.

[0002]

2. Description of the Related Art In a winding machine, as shown in FIG. 5 (a), a running film F is wound around a winding core 4 by a predetermined amount to form a winding roll 5, and then is wound around the next winding core 3 by rewinding. For,
The film is cut between the winding roll 5 and the new winding core 3,
For this cutting, as shown in FIG. 5 (b), a chevron-shaped cutting edge is formed on the film to be cut from a point a to both ends b, and a required angle θ _{2 is formed} , which is usually 30 °. The cutting blade 10 with respect to the running film F is shown in FIG.
As shown in (3), it is cut at a substantially right angle (θ ₁ = 90 °).

[0003]

However, in the case of the above-mentioned cutting, the cut film edge shows the saw blade shape or the chevron shape which is the cutting blade 10 as it is, and the loss of the film and the point when the film is wound on the next winding core. Breakage may occur, causing a problem. That is, as shown in FIG. 5B, the blade width is L,
The cutting edge is a and the both ends are b.
Assuming that the vertical distance (height of the chevron) is H, the traveling film traveling speed is V ₁ , and the descending speed of the cutting blade 10 is V ₂ , normally, V ₁ = V ₂ is satisfied. ), The film F has also moved from the a'position to the b'position by the time the side edge b of the cutting edge portion enters from the position where the cutting edge tip a first entered (the position a in the figure). , Therefore Figure 5
The chevron height H of the cutting blade of (b) becomes the chevron height H ′ of the film cutting shape of FIG. 6 (b), and the chevron shape of the cutting blade 10 appears as it is.

This is because the traveling speed V _{1 of the} film is constant, and the height of H'becomes smaller as the descending speed V ₂ of the cutting blade is gradually increased, and conversely the descending speed V of the cutting blade is decreased.
₂ is constant, which means that if the traveling speed V _{1 of the} film is gradually increased, the height H ′ of the chevron is further increased. In recent years, however, the production speed of the film is further increased and the chevron shape is increased. Has become a big problem.

In the cutting blade, the film has a large thickness (for example, 0.5 to 2 mm), polyester,
If it is a hard film such as polyethylene or hard vinyl chloride, it cannot be cut with a flat blade, and it is necessary to have a sharper saw blade shape or a chevron shape.

The present invention deals with the actual situation as described above, and in particular, finds out that the cutting edge portion of the cutting blade is slanted at a non-perpendicular angle with respect to the film and the projection is made, thereby forming a saw blade shape and a cutting edge shape. However, it is an object of the present invention to form a transverse straight cutting edge as if it were cut by a parallel blade without forming a saw blade shape or a mountain shape at the cutting edge.

[0007]

That is, a feature of the present invention which meets the above-mentioned object is a cutting device for cutting a running film, wherein a cutting blade has a chevron-shaped cutting edge portion, and the cutting edge portion base portion is continuous with the cutting edge portion. The chevron-shaped cutting edge portion has an obtuse angle with respect to the plate portion, is bent forward and protrudes, and can be thrust into the running film at a required angle. The angle of protrusion of the chevron-shaped cutting edge portion bent and projected with respect to the film is set based on the chevron shape, the traveling film speed, and the speed at which the cutting blade plunges into the film. Further, the present invention, in cutting the film using the above cutting device,
Another feature is a method in which the cutting blade is pierced with respect to the running film in the bending direction of the blade portion at a required plunging angle to cut.

[0008]

When the film is cut by using the cutting device according to the present invention, the tip position of the blade tip is in contact with the film,
Cutting starts, but when the film travels the required distance due to the descent and operation of the cutting blade that matches the running of the film, the end on the blade tip side is cut at a position parallel to the point where the tip first comes into contact. Therefore, it becomes possible to cut the tip of the blade portion and the edge of the blade portion in a straight line as if they were cut with a parallel blade.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the embodiments shown in the accompanying drawings.

1 to 3 show a first embodiment according to the present invention. As shown in FIGS. 1 and 2 (a) and (b), the cutting blade 1 has a point a and a point angle from the point a. A chevron-shaped cutting edge portion 2 having a chevron height H provided with both-sided blades extending to side edges b on both sides of the
And a plate portion 2'which is continuous with the base of the blade edge portion 2, and the chevron-shaped blade edge portion 2 has a plate portion 2 '.
On the other hand, it has an obtuse angle, that is, an acute angle (θ) with respect to the film to be cut, and is bent and projected forward. In this case, the angle θ formed between the film F to be cut and the chevron-shaped cutting edge portion 2 is the chevron-shaped film traveling speed and the descent when the cutting blade 1 is attached to a rod of a cylinder (not shown) and moves up and down. The angle is not necessarily uniform depending on the speed and the like, and an appropriate angle is selected according to each, but the practical range is 15 to 75 °. The angle θ ₂ formed by the side blades on both sides of the chevron of the cutting blade 1 shown in FIG. 1B is the same as that of the conventional cutting blade (see FIG. 5B), and is usually about 30 °.

The cutting blade 1 of the present invention is shown in FIGS.
As shown in FIG. 3, the plate portion 2 ′ is moved up and down at right angles to the traveling film F, and the film F is cut from the tip a of the cutting edge portion. Now, in FIG. b is the side edge of the blade edge portion 2, θ is the angle between the film and the blade edge portion, V ₁ is the traveling speed of the film, V ₂ is the descending speed of the cutting blade 1, the traveling length of the film is ₁ , and V ₁ =
Assuming that V ₂ and l = Hcos θ, the tip a of the cutting edge is shown in FIG.
When the film F is contacted at a position between the take-up roll 5 wound around the winding core 4 and the new winding core 3, the tip a of the cutting edge portion is at the position a'as shown in FIG. From this state, the blade tip 2 is l '
Just push it in, and when it comes to the state shown in (c), the blade end side edge b
Reaches point b ', where the film has run by l. At this time, this point b'is the position of the horizontal line of the point a'where the apex a of the cutting edge originally touched the film.

In this way, the tip a of the blade tip comes into contact with the film and begins to cut the film, but the cutting blade is operated in accordance with the running of the film, and the film runs for the distance l,
If the edge b on the blade tip side is just cut at the parallel position l'of the position a'where the tip a of the blade is initially in contact, the a'position and the b'position are parallel positions, and whether the cutting is also performed by the parallel blade. It can be cut in a straight line. If the position of the cutting edge 2 that cuts the film F is the same speed as the running of the film, the cuttability of the film will be better.

The above description is for the case where the cutting edge has a chevron shape. However, the cutting edge can be used in the same manner even if the cutting edge has a saw-tooth shape or is not a chevron but a tilted blade. Can be obtained.

FIG. 4 shows a second embodiment of the cutting blade according to the present invention. While the cutting blade 1 of the first embodiment has the plate portion continuously bent, the cutting edge portion 7 is It is formed by bending it into a dogleg shape, and is fixed to the substrate by welding or the like and fixed to the elevating plate 6 connected to the elevating cylinder with bolts or the like. With this cutting blade structure, the blade tip portion can be easily replaced, and it can be easily changed appropriately according to the type of film.

On the other hand, the cutting speed V ₂ of the film with respect to the traveling speed V ₁ is related to the relative angle θ between the film and the cutting edge portion. The higher the cutting blade speed, the larger the angle θ. it can. That is, when the angle formed by the blade portion 2 and the film F in FIG. 3 is θ, V ₂ /
V ₁ = tan θ, for example, V ₂ / V ₁ = 2
^{If m / sec} / 2 _{m / sec} , tan θ = 1, and θ is 45 °. Also, V ₂ / V ₁ = 4
^In tan θ of ^{m / sec} / 2 _{m / sec} , θ is about 63 °
Is. It can be seen that the angle θ can be increased if the descending speed of the cutting blade is faster than this.

Thus, according to the cutting method of the present invention, by setting the traveling film speed, the speed at which the cutting blade thrusts into the film, and the chevron shape and the relative angle between the film and the cutting blade, the cutting edge of the film is made straight. It is possible to obtain a good cut end.

[0017]

As described above, the present invention comprises the chevron-shaped cutting edge portion and the plate portion continuous with the cutting-edge base portion, and the chevron-shaped cutting edge portion makes an obtuse angle with respect to the plate portion and bends and projects forward. Is a method of cutting the configuration of the cutting blade and the cutting blade so that it can be thrust at a required angle with respect to the traveling film, and the cutting blade is thrust at the film at the blade edge angle, and the tip of the blade tip contacts the film, When the film runs after starting cutting, the chevron-shaped side blades sequentially cut the film in the width direction by the operation of the cutting blade suitable for this running, so that the sharp edges and the side edges are aligned. As with conventional cutting, there is no direct appearance of chevron or sawtooth shape of the cutting blade, therefore there is no loss of film and no tip breakage when winding on the next winding core. Has a significant effect serve a good film cutting. Since the present invention is a cutting blade having a chevron shape or a saw blade shape, there is an advantage that a thick film or a hard film can be cut without any trouble.

[Brief description of drawings]

FIG. 1 shows an outline of a cutting blade according to a first embodiment of the present invention, (a) is a perspective view of a main part, and (b) is a plan view of a cutting edge part.

2A and 2B are explanatory views of the use state of the cutting blade of FIG. 1, in which (A) is a front view and (B) is a plan view.

FIG. 3 is an explanatory view of the action of the above-mentioned cutting blade, (a) is an outline drawing of a winding process, (b) is an explanatory view in which a tip is in contact with the film, and (c) is a cutting blade as the film runs. It is explanatory drawing of the state which thrust.

FIG. 4 is a schematic view of a cutting blade according to a second embodiment of the present invention,
(A) is a plan view and (B) is a front view.

FIG. 5 is a view showing a cutting aspect of a conventional film, (a)
Is a front view, and (b) is a blade tip shape view.

6A and 6B show the above-mentioned conventional cutting mode, wherein FIG. 6A is a schematic perspective view and FIG. 6B is a cutting end state diagram.

[Explanation of symbols]

F film 1 cutting blade 2 cutting edge 2'plate part 3 New winding core 4 winding core 5 winding roll

Claims (3)

(57) [Claims] 1. A cutting device for cutting a running film, wherein a cutting blade comprises a chevron-shaped blade tip portion and a plate portion continuous with the blade tip portion base portion, and the chevron-shaped blade tip portion has an obtuse angle with respect to the plate portion. And bend forward and stick out,
A film cutting device characterized in that it can be inserted into a running film at a required angle. 2. The angle of plunging of the chevron-shaped cutting edge portion bent and projected with respect to the film is set based on the chevron shape, the traveling film speed, and the speed at which the cutting blade plunges into the film. Film cutting equipment. 3. When cutting the running film, the cutting device according to claim 1 or 2 is used, and the cutting blade is cut into the running film at a required plunging angle in the bending direction of the cutting edge. Characteristic film cutting method.