JP2001030191A - Cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting device (a slitter) to provide an increased life for a blade used in cutting of a tape at a manufacturing process for a magnetic tape, enhance the working efficiency of the process and improve productivity. SOLUTION: This cutting device comprises an upper blade spindle on which upper blades 30 are mounted at intervals of a specified distance; and a lower blade spindle on which lower blades 32 are mounted at intervals of a specified distance. A raw fabric film 35 is cut in a given width into a plurality of pieces with the upper and lower blades 30 and 32 engaged with each other during rotation of the two spindles. In a so formed cutting device, a blade flank 32b positioned opposite to one blade flank 32a of the lower blade 32 is formed at the lower blade 32. Even when one blade flank 32a of the lower blade 32 is worn, the preliminary upper blade 30 makes contact with the other blade flank 32b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting device preferably used for cutting a long body such as a magnetic tape.

[0002]

2. Description of the Related Art A magnetic tape used for video, audio, and the like has a structure in which a magnetic layer is formed on a plastic base film, and is basically manufactured as follows.

That is, a step of applying a magnetic paint on one surface of a long base film running at high speed between rolls, a drying step thereof, a calendar step of flattening the magnetic layer, And a slit step of cutting the base film into a narrow width.

Further details will be described with reference to the drawings.

FIG. 5 shows a typical process for manufacturing a magnetic tape. First, the base film 1 is unwound from a hub 2a and tension is applied to the guide rollers 3a, 3b, 3g.
The magnetic paint is applied to one surface of the base film 1 through the gap between the backup roll 4 and the gravure roll 5 through this c.

In the coating step, the gravure roll 5
The rotary machine rotates in a state where a part thereof is immersed in the magnetic paint 7 filled in the paint tank 6, and excess paint can be wiped off by the doctor blade 8.

The base film 1a on which the magnetic layer in the wet state is formed is introduced into the dryer 10 through the guide rollers 9a and 9b, where the magnetic layer is dried by, for example, hot air, and then constituted by a number of rollers 11a. The magnetic layer is passed through a calendar section 11, where the magnetic layer is flattened, and then wound around the hub 2 b.

Although a wide magnetic tape (raw film 1b) can be obtained as described above, the raw film 1b is sent to, for example, a slitting process as described below to be commercially available. It is common to cut into widths.

That is, in FIG.
b is fed out from the hub 2c, passes through a roll 3e, etc., and enters the cutting machine 23, where it is cut into a predetermined width by a rotating shaft 3f with an upper blade and a rotating shaft 3g with a lower blade, and the two magnetic tapes are cut. 1c, 1d, and after passing through roll groups 3g, 3h, 3i, 3j, 3k, 3l, are wound around each hub 2d, 2e to form a pancake 1e (the pancake is a predetermined length). (It refers to a long wound magnetic tape before it is cut into pieces.)

Conventionally, a slitter knife used for this kind of cutting is composed of an upper blade and a lower blade mounted on a pair of rotating shafts at regular intervals, and the lower blade 26 has a lower blade 26 shown in FIG.
As shown in the figure, the blade surface 26a made of cemented carbide is
440C and the same diameter collar 26b.

When cutting the raw film, the lower blade 26
The cutting edge of the upper blade 27 is brought into contact with the blade surface 26a, and the raw film is cut at these engagement portions during rotation.

As a matter of course, the wear occurs as the lower blade 26 and the upper blade 27 are used. This is remarkable because the object to be cut is a film with a magnetic layer. Therefore, conventionally, the worn upper blade 27 and lower blade 26 are detached from the upper blade shaft and the lower blade shaft, which are the rotating shafts, and these spare parts (spare parts) are attached instead. The removed upper blade 27
And the lower blade 26 are sent to a polishing step for reuse (the lower blade 26 is reduced by about 0.10 to 0.30 mm by one polishing).

The period from the start of use of the slitter knife to the polishing process, that is, the life of the slitter knife is about 500 to 1,000,000 m in the case of a cone-type upper blade, and the slitter knife is sent to the polishing process in this cycle.

[0014]

However, recently, as the cutting speed has been increased, the life of the slitter knife has been shortened, and its frequency of replacement has been increasing.

As described above, with the conventional slitter knives, it is extremely difficult to increase the operation rate, and the number of incidental operations such as mounting of spare parts increases, which hinders the improvement of the productivity of the magnetic tape.

The present invention has been made in order to improve the above circumstances, and has an object to extend the life of a blade in a cutting process of a magnetic tape, to increase an operation rate of a manufacturing process,
An object of the present invention is to provide a cutting device capable of improving productivity.

[0017]

That is, a cutting device according to the present invention is configured such that a first blade and a second blade are engaged with each other and an object to be cut is cut at the engaged portion. In the apparatus, a cutting state in which the first blade has a blade surface on each of both surfaces thereof, and the second blade engages with one blade surface of the first blade, and the one blade surface And a cutting state in which it engages with the other blade surface side opposite to the cutting surface.

As described above, according to the cutting apparatus of the present invention, the first blade engaged with the second blade can take two cutting states, so that one blade surface of the first blade is worn. However, the other blade surface can be used for cutting without requiring replacement of the blade. Therefore, incidental work accompanying the replacement can be reduced, and the life of the first blade can be extended.

When the technical concept of the present invention is applied to a cutting process in which a cutting blade is easily damaged, for example, for cutting a magnetic tape, the operation rate of the process is increased as described later, and the productivity is steadily improved. Can be.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is preferably applied to a cutting device (slitter) for a long object such as a magnetic tape. In other words, it has a first blade attached to one rotating shaft at regular intervals and the second blade attached to the other rotating shaft at regular intervals. A slitter configured such that a cut object is cut into a predetermined width in a longitudinal shape, wherein the second blade is engaged with the one blade surface side of the first blade, and the spare second It is preferable that a blade engages with the other blade surface of the first blade.

As described above, the second blade does not necessarily need to use a spare part (spare). That is, when the second blade is not used much and the degree of wear is small, the first blade can be directly applied to another blade surface without using a spare part.

In the present invention, there are various preferable conditions for the first blade and the second blade.

For example, as the second blade, a straight type having a straight blade portion can be used, but a cone type bent at a fixed angle, preferably 2 to 5 ° on the blade portion side is preferable.

And a known spring means suitable for the second blade for pressing the second blade against the first blade;
For example, it is preferable to attach a coil spring or a leaf spring.

The thickness of the second blade is not particularly limited as long as the durability and the sharpness of the blade are not significantly affected, but the thickness is preferably 0.3 to 0.6 mm. If the thickness is less than 0.3 mm, the rigidity is insufficient,
This also affects the cutting width, and if it exceeds 0.6 mm, the edge of the object to be cut tends to have a problem in quality.

When cutting a long body or the like, the first blade and the second
It is necessary that the second blade is in an engagement state with the first blade from the peripheral surface of the first blade by 0.2 to 0.4.
It is desirable to dig at a depth of mm. If the depth of the bite is less than 0.2 mm, cutting will be hindered, and if it is more than 0.4 mm, cracks will be easily formed on the cut surface.

The material of each of the blades may be a material known in the field of cutting of this type, but at least one of the two blade surfaces of the first blade is made of a super-steel material (for example, a super hard material). It is preferable to be formed of an alloy (main component, WC).

From the standpoints of material cost savings and durability, the first blade has two blade surfaces formed of the same super-steel material as described above, and a stainless steel (for example, SUS440C) or an intermediate portion made of ceramic.

Hereinafter, the present invention will be described more specifically by way of preferred embodiments with reference to the drawings.

FIG. 1A shows an embodiment in which the present invention is applied to a magnetic tape cutting apparatus.
A rotatable upper blade shaft 31 to which a super steel upper blade 30 is attached;
Similarly, a rotatable lower blade shaft 3 having a super steel lower blade 32 attached thereto.
And 3. In this embodiment,
The upper blade 30 is of a cone type that bends at 2 to 5 degrees on the blade side.

Each upper blade 30 is made of a stainless steel collar 3.
The upper blade shaft 31 is inserted through the upper blade shaft 31 at regular intervals, and is pressed by the coil spring 34 against the blade surface of each lower blade 32 (the pressing force is usually 200 to 400 g). Each lower blade 32
Also, through the stainless steel collar 33a, the lower blade shaft 33
And is inserted at regular intervals. The attachment of the collars 31a, 33a to the upper and lower blade shafts 31, 33 in this manner corresponds to the width of the collar, and the raw film is fixed to a fixed width, for example, 8 mm, 1/2 inch, 3/4 inch, 1 inch.
This is for cutting into / 8 inch or 1 inch magnetic tape.

In such a configuration, the cutting to the magnetic tape is performed at the engagement portion between the lower blade 32 and the upper blade 30, and when the two blades are rotated and slid, the raw film 35 is cut along a dashed line in FIG. As shown, it is cut into a plurality of magnetic tapes having a predetermined width.

After performing this cutting for a long time, both the upper blade 30 and the lower blade 32 gradually wear, and the cut edge of the tape begins to be affected, and furthermore, the life of both blades is exhausted, making it impossible to use or difficult. .

When such a situation is reached, the pressing of the upper blade 30 against the lower blade 32 is released, and the upper blade shaft 31 is removed from the cutting device with the upper blade 30 attached.

Then, a separately prepared spare upper blade 3
1 is assembled to the lower blade shaft 33 as shown in FIG. 1 (B). Alternatively, the upper blade 30
Only the spare may be used as the spare, and the upper blade shaft 31 may be used as it is, that is, the upper blade shaft 31 from which the worn upper blade 30 is removed. In this case, when attaching a spare upper blade to the original upper blade shaft 31, the collar 31a is detached and attached while being moved as appropriate.

In any case, at the time of assembling, as shown in FIGS. 1B and 2B, the spare upper blade 30 is attached to the other worn blade surface 32b of the lower blade 32. At the same time, a pressing force is applied to the blade surface 32b by a coil spring 34 or the like from a direction opposite to that of FIG.

Thus, the cutting of the magnetic tape can be restarted. Therefore, in this embodiment, two sets of upper blades (including shafts) are used in combination with one set of lower blades (including shafts).

As described above, in this embodiment, since both surfaces of the lower blade 32 are formed on the blade surfaces 32a and 32b, even if one surface thereof is worn, the other surface can be used for cutting the magnetic tape.

Therefore, even if the life of one of the blade surfaces is expired by the first cutting, the other blade surface can be used. At that time, it is not necessary to replace the lower blade with a spare part. The accompanying work can be reduced, and the life of the lower blade can be doubled.

When the magnetic tape is cut to 1/2 inch by using the conventional cutting device and that of the present invention, the former requires a cutting blade replacement time of about 6 hours every 500 to 1,000,000 m. However, according to the cutting apparatus of the present invention, only the upper blade needs to be replaced when compared with the same cutting length, so that the work time required for blade replacement is as short as about 1.5 hours. In the present invention, one lower blade can be used for two upper blades before the lower blade is replaced, so that the lower blade can be used twice as long as the conventional one.

When the service life of the blade has expired in the second cutting, that is, after the both blade surfaces of the lower blade have been used, it is necessary to replace both upper and lower blades. Replacement time is required.

The above embodiment may be variously modified without departing from the gist of the present invention.

For example, in the above-described embodiment, the entire lower blade is made of a super-steel material, but parts other than the blade surface may be made of stainless steel or ceramics.

That is, as illustrated in FIG. 3, both blade surfaces 32a and 32b of the lower blade 32 are formed of a super-steel material, and an intermediate portion 32c sandwiched between the both blade surfaces is made of stainless steel (for example, SU).
S440C) or ceramics. These widths are as follows: blade surface 32a: intermediate portion 32c: blade surface 32b = 1:
It may be 2: 1.

With such a so-called sandwich structure, the material cost can be reduced, and the hardness of the lower blade 32 can be reduced by appropriately adjusting the hardness of the intermediate portion or the surface other than the blade surface with respect to the upper blade. It is possible to increase the durability and extend the life thereof, and it is suitable for narrow width (for example, 1/8 inch width) slitting.

However, the cutting apparatus of the present invention is not limited to a long body such as a magnetic tape, but can be preferably used for cutting other thin bodies into a plurality in the longitudinal direction.

[0047]

As is clear from the above, according to the cutting device of the present invention, the first blade engaged with the second blade can take two cutting states. Even if one of the blade surfaces is worn, the other blade surface can be used for cutting without having to replace the blade, and there is no need to replace the first blade with a spare part. Therefore, incidental work accompanying the replacement can be reduced, and the life of the first blade can be extended.

[Brief description of the drawings]

FIG. 1 is a side view of a cutting device according to an embodiment of the present invention, in which (A) shows a state at the start of a first use, and (B) shows a state at the time of a second use with an upper blade replaced. Each is shown.

FIG. 2A is an enlarged side view of the lower blade in the state of FIG. 1A, and FIG. 2B is an enlarged side view of the lower blade in the state of FIG.

FIG. 3 is a configuration diagram of a lower blade of a cutting device according to another embodiment of the present invention.

FIG. 4 is a configuration diagram of a lower blade of a conventional cutting device.

FIG. 5 is a flowchart showing a conventional magnetic tape manufacturing process.

FIG. 6 is a flowchart showing a cutting process of the raw film obtained in the manufacturing process.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base film, 4 ... Backup roll, 5 ... Gravure roll, 6 ... Paint tank, 10 ... Dryer, 11 ... Calendar part, 30 ... Upper blade, 31 ... Upper blade shaft, 31a ... Upper blade collar, 32 ... Lower Blade, 32a ... One blade surface of lower blade, 32b ...
The other blade surface of the lower blade, 32c: middle part of the lower blade, 33a lower blade collar, 34: coil spring, 35: raw film

Claims (9)

[Claims] 1. A cutting device in which a first blade and a second blade are engaged with each other, and an object to be cut is cut at the engaged portion. And a cutting state in which the second blade engages with one blade surface of the first blade, and a cutting state in which the second blade engages with the other blade surface facing the one blade surface. A cutting device capable of performing any of the following states. 2. The apparatus according to claim 1, further comprising: a first blade attached to one of the rotating shafts at regular intervals; and the second blade attached to the other rotating shaft at regular intervals. A slitter configured to cut the object to be cut into a longitudinal shape at a predetermined width at a portion, wherein the second blade is engaged with the one blade surface side of the first blade, and a spare The second blade is the first blade
The cutting device according to claim 1, wherein the cutting device engages with the other blade surface of the blade. 3. The cutting device according to claim 2, wherein the second blade is formed as a cone type bent at a constant angle on the blade portion side. 4. The cutting device according to claim 3, wherein the angle is 2 to 5 °. 5. The cutting device according to claim 1, wherein a spring means for pressing the second blade against the first blade is attached to the second blade. 6. The cutting device according to claim 1, wherein the second blade has a thickness of 0.3 to 0.6 mm. 7. A depth at which the second blade bites from the peripheral surface with respect to the first blade is 0.2 to 0.4 mm.
The cutting device according to claim 1. 8. The apparatus according to claim 1, wherein at least one of the two blade surfaces of the first blade is formed of a super steel material.
The cutting device according to claim 1. 9. The device according to claim 8, wherein the first blade is constituted by both blade surfaces formed of a super steel material and an intermediate portion made of stainless steel or ceramic sandwiched between the both blade surfaces. Cutting device.