JP2006142424A - Thomson blade for cutting film or sheet and cutting method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a Thomson blade capable of surely cutting a lid body to be heat-sealed to a container for packaging as a sufficient lid body without cracks even if it is a thin and fragile film or sheet. <P>SOLUTION: The Thomson blade 10 is used for punching the film or the sheet gripped by a gripper. A plurality of saw blades 11 are formed on the cutting edge of the Thomson blade 10. The tip of each saw blade 11 is sharpened. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a Thomson blade for cutting a film or sheet that becomes a lid of a packaging container formed in a cup shape by, for example, a synthetic resin, and a film or sheet cutting method using the Thomson blade.

  The packaging container made of synthetic resin formed in a cup shape is filled with semi-solid food such as yogurt, cut fruit soaked in syrup, bees, etc. It is made to cover and seal with. In recent years, the opening of this type of packaging container is often sealed by heat-sealing a film or sheet.

  A method for sealing an opening in a packaging container by heat sealing such a film or sheet is exemplified in Patent Document 1 or Patent Document 2, for example.

  Patent Document 1 discloses a “packaging container sealing method and sealing device”. Specifically, “a container body having a flange formed of a heat-weldable material and a container body covered with a flange”. In a packaging container composed of an edge that is crowned and abutted against the flange part, and a lid formed of a heat-weldable material with a lid part whose inner side is lower than the flange part when crowned, After the container body is filled with the object to be packaged, the lid body is crowned, a poly film having a silicon coating is interposed on the lid body, the heating body is brought into contact with the edge of the lid body, the container body flange portion and the lid A method of sealing a packaging container characterized in that a body edge is welded and sealed, and as shown in FIG. 7, "a container body provided with a flange formed of a heat-weldable material on a conveyance path" Supply mechanism portion, a filling material filling mechanism portion into the container body, and a frame when the container body is crowned. A lid body that is formed of a heat-weldable material with an edge portion that comes into contact with the edge portion and a lid portion that is lower than the flange portion at the time of crowning into a container body that accommodates a packaged article and is transported A polyfilm having a silicon coating is disposed above the lid body of the lid body mounting mechanism section to be crowned and the transported lid body container body, and the heating body is disposed on the edge of the lid body with the film interposed therebetween. This is a packaging container sealing device in which a heating mechanism portion that abuts and seals the flange portion of the container body and the lid edge portion is sealed.

  And in paragraph 0013 of this patent document 1, "the heating mechanism unit 5 is a lid of a container B that transports the film 51 from a film supply unit 52 that rolls a polyfilm 51 having a silicon coating in a roll shape. d is provided so as to pass through the upper part and be taken up by the take-up part 53, and is provided with a heating body 54 that moves up and down and contacts the edge of the lid d through the film 51. "And only how to cut the film 51 remains unclear.

  On the other hand, Patent Document 2 describes an invention relating to “a packaging container closed with a film and a film edge processing method”. As shown in FIG. 8, as shown in FIG. The open upper surface of the container main body formed to be accommodated is heat-sealed on a jaw portion extending a predetermined length outward from the upper peripheral edge of the container body, and cut at a portion slightly protruding outward from the jaw edge. Is closed, and the film is closed so that the protruding portion of the film edge is curled to cover the jaw edge. , “The film is cut at a part slightly protruding outward from the rim of the jaw”.

  In general, the film or sheet that should be the lid of this type of packaging must be cut mechanically or automatically, but in this case, it should be cut neatly into a shape or size as designed. Not only can the chip be generated, especially if the food is sealed. This is because the chips should not be eaten with food. In that respect, in Patent Documents 1 and 2, how to cleanly cut a film or a sheet is not regarded as a problem as much as it can be said.

  How to cut a film or sheet neatly can be found in Patent Document 3 or Patent Document 4 having a different “technical field” from the above-mentioned Patent Documents 1 and 2. Patent Document 3 describes an invention related to a “plastic sheet cutting device”. As shown in FIG. 9, mainly, a “work table fixed on a base and an attachment member provided on the base are provided. An air cylinder with a guide rod fixed via the blade, and a blade holder that is connected to the air cylinder with the guide rod, fixes the Thomson blade, and is provided with a pressing plate that is pressed and biased downward through an elastic member. The weight of the air cylinder with a guide rod is movable up and down, and a lock device that holds the weight in the raised position, and holds the plastic sheet placed on the work table with a pressing plate, Freely drop the weight onto the blade holder and cut the plastic sheet with the work table via the Thomson blade. It discloses the invention having the construction such plastic cutting device for a seat "characterized by.

  In other words, in this Patent Document 3, a “Thomson blade” is adopted as the cutting device. However, the use of a Thomson blade for cutting this kind of film or sheet itself is described in “Molding Trimming” in Patent Document 4. The apparatus, the mold for trimming and the molding trimming method "also in claim 16," The cutting blade is a Thomson blade, and the molding trimming apparatus according to any one of claims 1 to 15 ". As is said, it is a general technique.

  As pointed out in paragraph 0003 of the document, the inventor of Patent Document 4 stated that “the trimming is performed by pressing the Thomson blade against the resin-made backing plate. In addition, as described in paragraph 0045 of the document 4, “the unevenness removing operation for finely adjusting the height of the blade performed when the Thomson blade is replaced” was complicated. When the locator 45 is in a predetermined ascending position, the lower side of the Thomson blade 48 is located below the lower surface of the locator 45. The locator 45 moves from the descending position to the ascending position with reference to the upper table 31. By doing so, the Thomson blade 48 is lowered together with the upper table 31, and the periphery of the molded product pressed and held by the locator 45 is pressed and cut. Since the periphery of the molded product is pressed and cut, there are few shavings due to trimming and the appearance of the cut surface is good, and the Thomson blade can be made into various shapes, so The periphery can be trimmed in various shapes, and the shape of the inner surface 49a of the holding frame 49 may be formed in accordance with the shape of the outer surface of the Thomson blade "(see FIG. 30). However, there was no intention to improve the Thomson blade itself.

  In any case, in the techniques of cited references 3 and 4, as shown in FIG. 6, a cradle (base plate or work table) is placed on the lower side of the film or sheet to secure a portion where the blade tip of the Thomson blade is recessed. Therefore, if the surface of the cradle is not sufficiently flat, it is considered that the finished product is not cut or trimmed. Moreover, since the cradle is scratched each time by the Thomson blade, it is considered that the cradle must always be replaced in order to be able to perform beautiful cutting and trimming.

  By the way, it has been desired that a film or sheet to be used as a lid of this type adopts a “brittle” material made of “biodegradable resin” so as to simplify “garbage disposal”. There is an increasing need to reduce the thickness to facilitate degradation. For this reason, efforts are being made to reduce the thickness of the film or sheet to be a lid of this kind to 50 microns or less, and the film or sheet to be a lid of a packaging container is made even more "fragile". It is becoming.

  Thus, the thin or brittle film or sheet uses the Thomson blade described in the above-mentioned Patent Documents 3 and 4, so that it is clean and does not generate chips as a lid of the packaging container. In order to cut it to, the Thomson blade configuration or structure must be devised.

The method of cutting the thin or brittle film or sheet by devising the configuration or structure of the Thomson blade is a patent document 5 that is an invention in a technical field completely different from the above-mentioned patent documents 1 to 4. Alternatively, Patent Document 6 describes a certain amount.
Japanese Patent Laid-Open No. 10-81304, claims, paragraph 0013, representative figure Japanese Patent Application Laid-Open No. 11-105929, claims and representative diagrams Japanese Patent Laid-Open No. 2002-187093, Claims, Representative Diagram Japanese Patent Application Laid-Open No. 2004-9698, Claims, Paragraph 0003, Step 0045, Representative Diagram Japanese Patent Laid-Open No. 2001-4516, Abstract, Claims, Representative Diagram Japanese Patent Laid-Open No. 2002-283292, summary, representative diagram

  Patent Document 5 describes “a cutting blade and a tear test device for a tear test”, and this “a cutting blade and a tear test device for a tear test” describes “a cutting blade and a tear test device for a tear test”. The purpose of this is to provide a cutting blade and a tear test device for tearing tests that can suppress the occurrence of lamination, increase the number of tests that can be adopted in conformity with regulations, and easily obtain accurate tear resistance values. '' is there. As shown in FIG. 11, this “blade or device” is “a cutting blade having a thickness of 0.9 mm or less. The maximum thickness of the cut portion is 1.5 mm or less, and at least on the test pieces on both side surfaces. A cutting blade connected to the blade base with a smooth curved surface with a polished surface, a tear test device that operates based on the pendulum principle with respect to a test piece held by a grip that also serves as a notch forming means. And an elastic sheet sandwiched between the test piece and the test piece ”.

In the “blade or device” described in Patent Document 5, as described in claim 6, “the thickness of the elastic sheet is 0.5 mm or more and 4 mm or less, and the Young's modulus is 0.2 kg / mm 2 or more 6.
It is intended to be “00 kg / mm 2 or less”, and does not have a thickness of “50 microns or less” as the subject of the present invention. In other words, the “blade or device” of this Patent Document 5 is for performing a “tear test” in conformity with JIS-K7128, and is used for packaging a film or sheet having a brittle physical property of 50 microns or less. What is cut as a lid heat-sealed in a container cannot be employed at all, even if it is a hint to some extent.

  Patent Document 6 describes "a method for cutting a polyether sulfone resin film". As shown in FIG. 12, the invention of this document mainly includes a "bonded PES film as a liquid crystal display substrate". For the purpose of "providing a cutting method that does not cause defects such as generation of cracks efficiently", and "to a wooden mold for punching paper containers, with a one-edge Thomson blade on the inside, and a 0.5 to the outside. It has a configuration such as “a method for cutting a polyether sulfone resin film, which is attached by being tilted once and the polyether sulfone resin film is punched out”.

  However, the invention of this patent document 6 also relates to a method of cutting a thick PES film of 300 μm or more efficiently and with high dimensional accuracy so that it can be used as a liquid crystal substrate. As described, it is intended for a considerably thick film, and is considered not to be applicable to a film of 50 microns or less targeted by the present invention.

  In particular, as for the packaging container for storing foods in recent years, the film or sheet constituting the lid body heat-sealed to the packaging container is formed as described above with the biodegradable resin itself. A biodegradable resin such as polylactic acid has been adopted to have a thickness of 50 microns or less. The reason is that if the remaining food is left in the container and discarded in the ground, it can be decomposed and returned to the soil at an early stage.

  When a film or sheet having a thickness of 50 microns or less is formed of a biodegradable resin, the physical properties are naturally thin and brittle, and mass production of lids from such a thin and brittle film or sheet is possible. Attempting to do so causes the following problems:

  When a thin and fragile film or sheet is punched as a lid with a conventional Thomson blade, a number of cracks are generated around the punched lid, as well as a number of cracks in the remaining film or sheet cuts. appear. The reason is considered that the force by the Thomson blade is applied not only on the line to be cut on the film or sheet but also on the periphery thereof before completely separating as a lid. In particular, many of these cracks are likely to occur when the film or sheet is a single layer of polylactic acid (which has been required to do so).

  If a crack occurs around the lid, not only does the crack disturb the outer shape of the lid, but the product value of the packaging container is significantly reduced. The inside of the container may be reached and complete sealing may not be possible. Further, when the lid that is heat-sealed from the packaging container is peeled off, the lid may be partially broken due to the crack, and the entire lid cannot be peeled cleanly.

  On the other hand, this type of lid is formed by punching a large number of films or sheets simultaneously (so-called multi-cavity), and the remaining film or sheet has a large number of holes from which the lid is punched. The surroundings are connected by a “thin remainder” and are continuously wound up as waste material. At this time, if there is a crack around the hole, the “thin remaining portion” is cut by the force at the time of winding, and continuous winding of the waste material becomes impossible. If the waste material cannot be continuously wound up, the cutting device will stop, and it will have to be returned to a state where it can be wound up by human hands, resulting in very poor work efficiency. .

  Therefore, the present inventors can reliably cut a film or sheet having a brittle physical property of 50 microns or less into a sufficient one that does not crack as a lid heat-sealed to a packaging container. As a result of various studies on what to do, the present invention has been completed.

  That is, the object of the present invention is a Thomson blade that can reliably cut a lid that will be heat-sealed to a packaging container from now on without being cracked, even if it is a thin and brittle film or sheet And a cutting method using the same.

In order to solve the above problems, first, the means taken by the invention according to claim 1 will be described with reference numerals used in the description of the best mode described below.
"Thomson blade 10 for punching the film or sheet 30 gripped by the gripper 20,
To together to form a multiple saw blade 11 cutting edges sharpened tip of the Thomson blade 10, any at least one side of each saw blade 11, characterized that you formed ho processing unit 12 Thomson blade 10 "
It is.

In other words, Thomson blade 10 according to the claim 1, as shown in FIG. 3, to form a cutting edge thereof multiple saw blade 11 that has sharpened tip (FIG. 3, shown below), the saw blade 11 In this case, the scissors processed portion 12 is formed on at least one of the side surfaces . Of course, the Thomson blade 10 is formed as a band before being installed in the cutting device, but is cut out from a film or sheet 30 so as to punch out a disc-like or square lid. When installed in the apparatus, the Thomson blade 10 is such that the tip of each saw blade 11 forms a closed curve.

As shown in FIG. 5, when the film or sheet 30 gripped by the gripping tool 20 is punched by the Thomson blade 10, a hole as shown in FIG. 2 is formed in the film or sheet 30 by the tip of each saw blade 11. Ru is formed. In order to make it easy to explain the state of FIG. 2, referring to FIG. 3 and FIG. 4, the case where the scissor machining portion 12 is not formed on at least one side surface of each saw blade 11 will be described. (A) shows the cross section of each saw blade 11 and the change in the position of the film or sheet 30 when this saw blade 11 pierces the film or sheet 30 in order from the top by horizontal lines . (B) is a plan view showing holes formed in the film or sheet 30 at that time and the surrounding state.

In the state of the uppermost stage in FIG. 4 when the punched portion 12 is not formed , each saw blade 11 is in contact with the film or sheet 30 to form a small hole, and the film or sheet around each hole A force is applied to 30 in the direction indicated by the arrow in the figure. Next, in the intermediate state of FIG. 4, the force applied to the sheet 30 becomes the left and right side directions and the peak direction of each saw blade 11, and the small hole shown in the uppermost stage of FIG. 4 becomes a triangular hole. Increased.

At this time, the holes in each triangle, the portion corresponding to the left and right sides and crests of the saw blade 11, a force to be widen each apex portion of the triangle is applied, among these forces, ho machining Since the lateral force in FIG. 4 when the portion 12 is not formed is along the outer shape of the lid to be formed, it is used for punching the lid. In contrast, the force acting on the downward apex in FIG. 4 is used to further open a hole into which the saw blade 11 enters. Then, when reaching the final stage of the lowermost stage in FIG. 4 , the holes of the film or sheet 30 are sufficiently expanded to connect the triangular holes, and punching is completed.

  (Delete)

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On the other hand, in the Thomson blade 10 according to the present claim 1 ,
“Each saw blade 12 is formed on at least one side surface of each saw blade 11”
It was characterized by.

That is, the Thomson blade 10, as shown in FIG. 1, in either of at least one side of each saw blade 11 is obtained by forming a ho processing unit 12, by the ho processing unit 12, FIG. 4 (B) The force concerning the lower vertex of the triangle shown in the middle row can be made smaller. When the Thomson blade 10 having the scissors machining portion 12 formed on each saw blade 11 is used as described above, an action as shown in FIG. 2 is exhibited.

In the uppermost state of FIG. 2 , each saw blade 11 abuts on the film or sheet 30 to form a small hole, and the film or sheet 30 around each hole has an arrow in the figure. The force is applied in the direction indicated by the same as in the case of claim 1 described above. Next, in the intermediate state of FIG. 2, the force applied to the sheet 30 is in three directions, the left and right sides of each saw blade 11 and the direction in which each saw blade 11 is thickened. Since the punched portion 12 has been formed, the small hole shown in the uppermost stage in FIG. 2 is enlarged into a trapezoidal hole.

At this time, each apex portion of each trapezoidal hole is applied with a force to expand it, but most of these forces are lateral forces in FIG. Thus, the force acting downward in FIG. 2 is very small. That is, most of the force applied by each saw blade 11 is along the outer shape of the lid to be formed, and is used for punching the lid. In other words, the Thomson blade 10 according to claim 2 has almost no force other than the force along the outer shape of the lid body due to the presence of the scissors processing portion 12 in each saw blade 11. Then, when reaching the final stage of the lowermost stage in FIG. 2 , the holes of the film or sheet 30 are sufficiently expanded to connect the trapezoidal holes, and punching is completed.

  In any of the above stages, each saw blade 11 of the Thomson blade 10 does not generate a crack in the film or sheet 30 that is different from the cutting position. In the remaining film or sheet 30 that has been removed, the cracks in question hardly occur.

Therefore, even if the Thomson blade 10 of this claim 1 is a thin and fragile film or sheet 30, the lid heat-sealed to the packaging container from now on can be surely cut as being sufficient without cracks. It has become.

In order to solve the above problems, the means adopted the invention according to claim 2, for engaging Ru Thomson blade 10 in the claim 1,
“Pitch between each saw blade 11 is 2 mm to 10 mm”
It is.

  That is, the Thomson blade 10 of the present invention has a large number of saw blades 11, but the pitch of each saw blade 11 does not have an effect in any range. The pitch between 11 is set to 2 mm to 10 mm for the following reason.

  The reason why the pitch between the saw blades 11 is preferably 2 mm or more is that when the pitch is 2 mm or less, it is not only difficult to make such a Thomson blade 10, but also the best in FIGS. 2 and 4. This is because it is difficult to form the holes shown in the upper stage. That is, the film or sheet 30 itself is damaged before each hole is opened. In addition, the reason why the pitch between the saw blades 11 is preferably 10 mm or less is that if the pitch is 10 mm or more, the arc or corner of the lid to be punched does not appear cleanly, and there are a plurality of reasons. This is because the meaning of forming the saw blade 11 disappears and cracks are likely to occur. Of these, the pitch between the saw blades 11 is most preferably about 5 mm.

Accordingly, the saw blade 11 of the second aspect, in addition to exhibiting the same function when being Noso the claim 1, easy processing, and it has become the one that can further suppress the occurrence of cracks.

In order to solve the above problems, the means adopted of engaging Ru invention in claim 3,
“The edge of the film or sheet 30 is gripped by the gripping tool 20 so that the film or sheet 30 is suspended in the air, and the tip is pointed toward the film or sheet 30 and at least one of them After pressing the tip of each saw blade 11 into the film or sheet 30 by pressing a Thomson blade 10 having a plurality of saw blades 11 each having a scissors processing portion 12 formed on the side surface , the film or sheet between the saw blades 11 is inserted. The method for cutting the film or sheet 30 is characterized in that the sheet 30 is cleaved and the film or sheet 30 is cut into a shape in which the saw blades 11 are aligned.
It is.

That is, inventions of the third aspect is using a Thomson blade 10 according to any of the claims 1 or 2, and brittle from soft film or sheet 30 punched out lid of the packaging container processing and manufacturing The method uses a Thomson blade 10 having a plurality of saw blades 11 having a pointed tip and at least one side surface of which a scissors machining portion 12 is formed, and is gripped by a gripping tool 20. The Thomson blade 10 having a plurality of saw blades 11 with sharp tips is pressed against the film or sheet 30 while the film or sheet 30 is left floating.

  In other words, this method of cutting the film or sheet 30 does not use a “cradle” that is necessary in the conventional method. That is, in the case of punching using a conventional Thomson blade, the “cradle” (a cradle or work table) shown in FIG. 6 is necessary, but in the present invention, this can be performed without using the cradle. It is what I did. The "cradle" that has been necessary in the past is deformed and partially destroyed by the intrusion of the Thomson blade 10, but by using the Thomson blade 10 that can eliminate this cradle, the cradle can be removed. This prevents the generation of “chips” that are likely to occur due to the presence of the swarf, prevents damage to the Thomson blade 10 itself, and simplifies the configuration of the entire cutting device.

  Of course, as shown by the dotted line in FIG. 5, the film or sheet 30 to be processed bends due to the absence of the cradle, but this bending causes the tip of each saw blade 11 to move to the film or sheet 30. This makes it easier to form the hole shown in FIG. 2 or FIG. When this hole is formed at one end, the film or sheet 30 between the saw blades 11 is torn by using this hole as a crack, and the saw blades 11 are lined up in the film or sheet 30. It becomes easy to cut into a shape.

Therefore, disconnect method of claim 3, the first aspect or using the Thomson blade 10 according to any of the 2, results to perform work without using and the cradle, a clean lid It can be surely punched from the film or sheet 30.

As described above in detail, in the Thomson blade 10 according to the present invention,
"Thomson blade 10 for punching the film or sheet 30 gripped by the gripper 20,
To together to form a multiple saw blade 11 cutting edges sharpened tip of the Thomson blade 10, any at least one side of each saw blade 11, and this formed a ho processing unit 12 '
The main feature of the structure is that it is possible to reliably cut the lid heat-sealed to the packaging container from now on even if it is a thin and fragile film or sheet 30 without cracks. The Thomson blade 10 that can be provided can be provided.

In the invention according to claim 3 ,
“The edge of the film or sheet 30 is gripped by the gripping tool 20 so that the film or sheet 30 is suspended in the air, and the tip is pointed toward the film or sheet 30 and at least one of them After pressing the tip of each saw blade 11 into the film or sheet 30 by pressing a Thomson blade 10 having a plurality of saw blades 11 each having a scissors processing portion 12 formed on the side surface , the film or sheet between the saw blades 11 is inserted. The sheet 30 was cut and the film or sheet 30 was cut into a shape in which the saw blades 11 are lined up. "
Therefore, even if the film or sheet 30 is thin and brittle, the lid heat-sealed to the packaging container can be surely cut as being sufficient without cracks. A cutting method can be provided.

  Next, the invention according to each claim configured as described above will be described with respect to the Thomson blade 10 which is the best mode shown in the drawings. The Thomson blade 10 of this best mode and a cutting method using the same are as follows. Since all of the inventions according to the above claims are included, the Thomson blade 10 of the best mode will be mainly described below.

  The film or sheet 30 targeted by the Thomson blade 10 according to the present invention is polylactic acid. As a result of a tear (cleavage) strength test of this polylactic acid, the results shown in the following Table 1 are obtained. It was.

図３及び図４には、本発明に係るトムソン刃１０の理解を助けるために、鎬加工部１２を形成していないトムソン刃１０の部分拡大図が示してあり、このトムソン刃１０は、図３の（ａ）に示したように、その刃先に複数のノコ刃１１を形成するとともに、図３の（ａ）及び（ｂ）に示したように、各ノコ刃１１の先端を尖らせたものである。なお、この図３に示したトムソン刃１０は、所謂「片刃タイプ」のものであるが、本発明は「両刃タイプ」のものにも適用できるものである。

In FIGS. 3 and 4, in order to facilitate understanding of the Thomson blade 10 according to the present invention, is shown a partial enlarged view of the Thomson blade 10 is not formed ho processing section 12, the Thomson blade 10 is As shown in FIG. 3 (a), a plurality of saw blades 11 are formed at the blade tip, and as shown in FIGS. 3 (a) and 3 (b), the tip of each saw blade 11 is sharpened. It is a thing. The Thomson blade 10 shown in FIG. 3 is a so-called “single-blade type”, but the present invention can also be applied to a “double-blade type”.

The Thomson blade 10 is formed using a steel material having a thickness of 1 mm, and the pitch (pitch interval) between the saw blades 11 is 5 mm. Note that the Thomson blade 10 shown in FIG. 3, Ho processing unit 12 Ikoto such to form the Ru der as described above.

  As shown in FIG. 5, such a Thomson blade 10 is pressed against the film or sheet 30 held by the gripping tool 20, so that a disc-like or rectangular lid is formed from the film or sheet 30. (Not shown) is punched out. When the Thomson blade 10 according to the present invention is used, a “cradle” as in the conventional cutting apparatus shown in FIG. 6 is not required at all.

The punched state of the film or sheet 30 by the Thomson blade 10 is as shown in FIG . That is, as the Thomson blade 10 is pressed against the film or sheet 30, cutting is performed from the uppermost stage in FIG. 4 to the middle and lowermost stages. Since the specific change during this time has been described above, it will be omitted.

1 and 2 show, the Thomson blade 10 according to the present invention is shown, in the Thomson blade 10, Ru each saw blade 11 to form the ho processing unit 12 tare. The illustrated upper end portion of the scissors processing portion 12 is positioned above the valley between the saw blades 11, and as a result, the opening formed by each saw blade 11 is as shown in the lowermost stage of FIG. 2. In addition, cutting can be performed while maintaining the trapezoidal shape.

The saw blade concerning this invention is shown, (a) is a partial expanded front view, (b) is sectional drawing. The state when cut using the saw blade according to the present invention is shown, (a) is a cross-sectional view showing the position of the film or sheet relative to the saw blade in a straight line, (b) is the hole at that time It is a fragmentary top view of the film or sheet which shows a shape. The saw blade for comparing with this invention is shown, (a) is a partial enlarged front view, (b) is a sectional view. The state when cut using a saw blade for comparison with the present invention is shown, (a) is a sectional view showing the position of the film or sheet relative to the saw blade in a straight line, (b) is at that time It is a fragmentary top view of the film or sheet which shows the shape of this hole. FIG. 3 is a partial cross-sectional view of a cutting device when a film or sheet is cut using the Thomson blade according to the present invention. It is a fragmentary sectional view of the cutting device when cutting a film or a sheet using a conventional Thomson blade. It is a schematic side view of the conventional lid punching apparatus. It is a partial expanded sectional view of another conventional lid punching device. It is a partial expanded sectional view of another conventional lid punching device. It is a fragmentary sectional view of the conventional punching apparatus. It is a perspective view of the inspection apparatus shown by literature 5. It is a fragmentary sectional view which shows the use condition of the conventional Thomson blade shown by the literature 6.

Explanation of symbols

10 Thomson blade 11 Saw blade 12 Spear processing part 20 Grasping tool 30 Film or sheet

Claims (4)

A Thomson blade for punching a film or sheet gripped by a gripper,
A Thomson blade characterized by forming a plurality of saw blades at the tip of the Thomson blade and sharpening the tip of each saw blade.   The Thomson blade according to claim 1, wherein a scissors machining portion is formed on at least one side surface of each of the saw blades.   3. The Thomson blade according to claim 1, wherein a pitch between the saw blades is 2 mm to 10 mm.   Hold the edge of the film or sheet with a gripper so that the film or sheet is suspended in the air, and press the Thomson blade having a plurality of pointed blades toward the film or sheet. By piercing the tip of each saw blade into the film or sheet, the film or sheet between each saw blade is torn, and the film or sheet is cut into a shape in which the saw blades are lined up A method for cutting a film or sheet.

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