JP5766886B2 - Flat blade cutting blade and green sheet cutting blade - Google Patents

Description

  The present invention relates to a flat cutting blade and a green sheet cutting blade.

  As a method of manufacturing a multilayer ceramic capacitor, a multilayer varistor, a multilayer coil, a multilayer piezoelectric actuator, etc., a paste-like sheet containing a mixture of dielectric ceramic powder and a binder is used, and these are laminated (called a green sheet) individually. There is a method in which the product is cut into product shapes, fired, and electrodes are attached to both ends.

  Here, in recent years, there is an increasing demand for capacitors to be reduced in size in order to be compatible with small machines such as smartphones, and therefore, high shape accuracy is required. In order to realize such a small-sized ceramic capacitor, it is necessary to pay attention to forming a cut surface as vertical as possible and not damaging the cut surface when cutting the green sheet. .

  As a cutting method of the green sheet, there are a method of cutting with a rotating round blade called a dicing method and a guillotine method of cutting with a flat blade-like cutting blade.

  Although the cutting accuracy of the dicing method is higher than that of the guillotine method, the material yield is worse than the guillotine method due to the generation of cutting waste, and the cutting speed is also inferior, so the size of the green sheet after cutting becomes smaller. The guillotine method is useful.

  Here, the flat blade-shaped cutting blade has a shape having a cutting execution portion that contributes to cutting, that is, a blade tip portion and a base portion (also referred to as a shank) having parallel surfaces to fix the cutting blade to the cutting device.

  Flat-blade cutting blades are sharp (low shear resistance during cutting), wear resistant, weld resistant to the workpiece, strong against buckling, and long life ("Life" as used herein refers to the point in time when the cross-sectional shape of the workpiece is damaged by chipping, and in the case of a multilayer capacitor cutting blade, peeling of the multilayer film occurs. And cutting blade life).

  For example, Patent Document 1 describes a structure in which a vertical cut surface can be formed by providing an arrow-shaped step in the cross-sectional shape of the blade edge (Patent Document 1).

  On the other hand, regarding the shear resistance, the shape of the cutting edge is particularly important. Considering damage to the workpiece, it is preferable that the blade has a thin blade and has a small tip angle. However, the strength becomes inevitable as the blade becomes thinner. Therefore, the cutting blade currently used is devised such as increasing the cutting edge angle of the cutting edge by providing one or more angles between the cutting edge and the base.

  For example, Patent Document 2 discloses a structure in which the cutting edge portion is formed with a plurality of concave curved surfaces, thereby reducing the shear resistance and increasing the buckling strength (Patent Document 2).

Japanese Utility Model Publication No. 63-197089 JP-A-10-217181

  However, even when the blade edge as in Patent Document 2 is used, it is difficult to ensure the strength of the edge of the blade edge.

  In addition, for example, hard materials such as cemented carbide other than stainless steel are used for the flat blade-shaped cutting blade. Especially when the material is a hard material, the material is rigid but difficult to cut and tough. Low and easy to chip. In addition, when the blade thickness is thin, even if it is a hard material, a shape excellent in workability is required because the blade tends to escape by pressing of a grindstone during processing, especially at the tip of the blade tip. However, in the structures of Patent Documents 1 and 2, accurate processing is not easy, and there is a problem in terms of practicality.

  Furthermore, when cutting, the dimensions of the workpiece are different on the left and right of the cutting blade, so if the product size is significantly smaller than the green sheet, the smaller one of the left and right workpieces will be It is necessary to suppress oblique cutting due to so-called “escape” that is easily deformed.

  However, the structures of Patent Documents 1 and 2 have a problem that the structure is not capable of suppressing oblique cutting.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cutting blade that satisfies both stable shape accuracy and cutting performance and can suppress oblique cutting.

  In order to solve the above-described problems, the present inventor has examined whether oblique cutting can be suppressed while ensuring the strength of the tip of the cutting edge and reducing the shear resistance during cutting.

  As a result, by devising the shape of the tip of the blade, especially by making the shape of the blade edge asymmetrical, the shear resistance during cutting can be reduced and oblique cutting can be suppressed without reducing the strength of the tip of the blade. As a result, the present invention has been made.

  That is, the first aspect of the present invention is a cutting edge which is formed so as to connect a flat base portion, left and right blade surfaces inclined so as to approach each other from both surfaces of the base portion, and the left and right blade surfaces, and having a convex curved surface. And the shortest distance between the intersection of two straight lines along the left and right blade surfaces and the tip of the blade edge is 1 μm or more and 10 μm or less, and the convex curved surface The length in the center line direction of the front end portion having a width is different from the left and right with respect to the center line of the base portion, the difference is not less than 1 μm and not more than 20 μm, and two straight lines along the left and right blade surfaces An internal angle of the crossing angle is 4 degrees or more and 60 degrees or less.

  According to a second aspect of the present invention, there is provided a green sheet cutting blade having the flat blade-like cutting blade according to the first aspect.

  According to the present invention, it is possible to provide a cutting blade that satisfies both stable shape accuracy and cutting performance and can suppress oblique cutting.

It is a side view which shows the outline of the shape of the flat blade-shaped cutting blade 1. FIG. FIG. 2 is a perspective view of FIG. 1. FIG. 3 is a cross-sectional view showing the tip shape of the flat blade-shaped cutting blade 1. FIG. 4 is an enlarged view of the vicinity of a connection portion 15 in FIG. 3. It is sectional drawing for demonstrating diagonal cutting. It is sectional drawing for demonstrating diagonal cutting. FIG. 3 is a schematic diagram showing a method for processing the tip of the flat blade-shaped cutting blade 1. FIG. 3 is a schematic diagram showing a method for processing the tip of the flat blade-shaped cutting blade 1. FIG. 3 is a schematic diagram showing a method for processing the tip of the flat blade-shaped cutting blade 1.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments suitable for the invention will be described in detail with reference to the drawings.

  First, with reference to FIGS. 1-6, the shape of the flat blade-shaped cutting blade 1 which concerns on embodiment of this invention is demonstrated.

  Here, as the flat blade-shaped cutting blade 1, a green sheet cutting blade is illustrated.

  As shown in FIG. 1, the flat blade-shaped cutting blade 1 is a flat plate-like base portion 5 having a rectangular planar shape, and a cutting execution portion that cuts the workpiece 100 and is provided on one long side of the base portion 5. A blade edge portion 7 is provided.

  The base 5 has a fixed portion 5a having a straight linear portion parallel to the fixing portion 3 of the cutting device, and a connecting portion 5b for connecting the fixed portion 5a and the blade edge portion 7 as shown in the figure.

  1 and 2, the length of the long edge direction of the flat blade-shaped cutting blade 1 is L, the length of the short side is H, the height of the blade edge portion 7 is H1, and the thickness of the flat blade-shaped cutting blade 1 is This is indicated as T.

  Further, as shown in FIG. 3, the blade edge portion 7 connects the left blade surface 9a, the right blade surface 9b, and the left blade surface 9a and the right blade surface 9b which are inclined so as to approach each other from the left and right surfaces of the base portion 5. It has a formed cutting edge tip 11.

  Here, as shown in FIG. 3, the cross-sectional shape of the blade edge portion 7 in the plate thickness direction is such that the intersection of the two straight lines 13a and 13b along the left blade surface 9a and the right blade surface 9b and the shortest of the blade edge tip 11 are shown. It is desirable that the distance X is 1 μm or more and 10 μm or less.

  When the above value is less than 1 μm, the cutting edge tends to be chipped. On the other hand, when it exceeds 10 μm, a large cutting resistance is generated when the cutting edge enters the workpiece 100. Furthermore, it tends to have a short life due to wear. More preferably, it is 1.5 μm or more and 5 μm or less.

  Moreover, as shown in FIG. 3, the flat blade-shaped cutting blade 1 has a convex curved surface in advance at the blade tip 11. Here, the convex curved surface means a curved shape that swells outward. By making the cutting edge tip 11 have a convex curved surface, both the strength of the cutting edge and the low cutting resistance can be achieved. Moreover, as shown in FIG. 4, when the cross-sectional shape in the plate | board thickness direction of the connection part 15 of the left blade surface 9a, the right blade surface 9b, and the blade edge | tip tip 11 is comprised with a curve, it becomes low cutting resistance and it is better.

  Further, the cross-sectional shape of the blade tip 11 in the plate thickness direction is such that the length of the blade tip 11 is left and right with respect to the center line 21 (a straight line passing through the center of the base 5 in the plate thickness direction and parallel to the short side direction). Is different. That is, the cross-sectional shape of the blade tip 11 in the thickness direction is asymmetric with respect to the center line 21.

  Specifically, in FIG. 3, the shortest distance Y1 on the left blade surface 9a side from the tip portion 17 of the blade tip 11 to the connection portion 15 and the shortest distance Y2 on the right blade surface 9b side are different from the center line 21. The difference (absolute value of Y1-Y2) is 1 μm or more and 20 μm or less.

  The reason for this shape will be described.

  As described above, when cutting using the flat blade-shaped cutting blade 1, because the dimensions of the workpiece are different on the left and right of the cutting blade, it is difficult to cut vertically. It is necessary to suppress oblique cutting due to so-called “relief” that is easier to deform when cutting when the dimension is smaller.

  Specifically, as shown in FIG. 5, for example, when cutting the workpiece 100 with a symmetrical blade, the right region 101 (product side) is flatter than the left region 103 (sheet side) of the cutting portion. The horizontal length of the blade-shaped cutting blade 1 is short.

  In this case, since the left region 103 is difficult to be plastically deformed during cutting (it is difficult to deform in the direction of A in FIG. 5), the cut surface is difficult to be obliquely cut, but the right region 101 is short in the horizontal direction. 5 has a degree of freedom of movement, and is deformed in the direction of arrow B shown in FIG. 5 at the time of cutting so as to escape from the blade edge. Finally, the cut surface of the right region 101 is compared with the left region 103, as shown in FIG. It tends to be oblique cutting as shown. This depends on the properties of the object to be cut and the size of the product to be cut from the object to be cut, but is more likely to occur as the size of the object to be cut is smaller in the horizontal direction (left and right direction in FIG. 5).

  Therefore, in the present embodiment, by making the cross-sectional shape of the blade tip 11 in the plate thickness direction different between the right and left in advance, the “escape” is absorbed and the oblique cutting is prevented.

  In this case, as shown in FIG. 6, Y1 and Y2 are compared, and the longer one (here, the left blade surface 9a side) is the shorter one of the objects to be cut in the horizontal direction (right side in FIG. 1). Cut toward area 101).

  When this difference (absolute value of Y1−Y2) is less than 1 μm, the left and right blade surfaces are almost bilaterally symmetric, and therefore the effect on oblique cutting is difficult to obtain when the product to be cut is small.

  On the other hand, if this difference exceeds 20 μm, there is a possibility of oblique cutting in the reverse direction, which is not desirable.

  This difference (absolute value of Y1−Y2) is more preferably 2 μm or more and 10 μm or less.

  Furthermore, as for the shape of the blade tip 11, it is desirable that the internal angle θ of the intersection angle between the two straight lines 13 a and 13 b along the left blade surface 9 a and the right blade surface 9 b is 4 degrees or more and 60 degrees or less.

  This is because when θ is less than 4 degrees, the cutting resistance becomes small, but chipping of the cutting edge tends to occur, and the cutting surface is adversely affected and the life of the cutting blade is deteriorated.

  When θ exceeds 60 degrees, a large load is generated when the cutting edge enters the workpiece 100, and the buckling resistance and the wear resistance are inferior. Further, in such a case, the amount of plastic deformation of the workpiece 100 is increased, the surface of the workpiece 100 is likely to be scratched, and the cut surface is more likely to be inclined rather than vertical, In addition, the cutting resistance increases.

  From the viewpoint of ensuring both the strength of the cutting edge and the low cutting resistance, it is more desirable that θ is 10 degrees or more and 30 degrees or less.

  The above is the description of the shape of the flat blade-shaped cutting blade 1.

  In addition, although the material which comprises the flat blade-shaped cutting blade 1 is suitably selected according to a to-be-cut object, as a specific material, carbon tool steel, a WC-Co type cemented carbide, etc. are mentioned, for example. Is mentioned.

  Next, the processing method of the blade edge | tip part 7 of the flat blade-shaped cutting blade 1 is demonstrated with reference to FIGS.

  Although the processing method of the blade edge | tip part 7 of the flat blade-shaped cutting blade 1 will not be specifically limited if the above-mentioned cutting edge shape processing is possible, The following methods can be illustrated.

  First, linear processing is performed on the tip (long side) of the connecting portion 5b of the base portion 5 to form a left blade surface 9a, a right blade surface 9b, and straight lines 13a and 13b.

  This linear processing is performed by, for example, polishing with a grindstone.

  Next, the process for forming the blade edge | tip tip 11 in the blade edge | tip part 7 is performed.

  As described above, since the shape of the blade tip 11 has a convex curved surface, the blade tip is too thin in the press working with a grindstone as in the case of forming the left blade surface 9a and the right blade surface 9b. Therefore, the cutting edge easily escapes from the grindstone during processing, and stable processing is not easy.

  Therefore, the cutting edge tip 11 can be processed by (1) a method of forming the cutting edge tip 11 in a solution containing abrasive grains, or (2) a solid material in which abrasive grains or other hard materials, that is, metal powder or ceramic powder are mixed. For example, there is a method of forming the blade tip 11 by using.

  Hereinafter, a specific processing method will be described.

  First, the method shown in (1) is, as shown in FIG. 7, in which a solution 201 having a hard material is filled in an appropriate container 203, and only the cutting edge portion 7 of the flat blade-shaped cutting blade 1 is put into the solution 201. In this method, the hard material in the solution 201 and the blade edge portion 7 are brought into contact with each other to form the blade edge tip 11 by reciprocating for a certain time in the blade spanning direction.

  Here, as a specific example of the hard material, high hardness diamond grains are preferable because a short processing time is required, but other metal powders and ceramic powders may be used.

  Moreover, the solvent of the solution 201 is water, for example.

  Next, the method shown in (2) is, as shown in FIG. 8, by cutting the solid material 205 mixed with the hard material powder with the flat blade-shaped cutting blade 1, the hard material in the solid material 205 and the cutting edge. This is a method of forming the cutting edge tip 11 on the cutting edge portion 7 by performing processing by bringing the portion 7 into contact.

  Here, as the solid material 205, for example, a clay-like material may be mentioned.

Examples of the hard material include diamond, W, Mo, WC, Al ₂ O ₃ , TiO ₂ , TiC, TiCN, SiC, Si ₃ N ₄ , and BN powders.

  As for the powder particle size of these hard materials, the average particle size of secondary particles is preferably 1 μm or less in terms of Fsss (Fisher Sub-Sieve Sizer) particle size. This is because if it exceeds 1 μm, chipping may occur in the processing of the blade edge surface. Further, the finer the particle, the better the shape accuracy of the flat blade-shaped cutting blade. However, it takes time to process, so in this range, it is initially processed with particles of a size close to 1 μm, and the finish is smaller than 1 μm. It is more preferable to process with hard material particles of a size. By uniformly dispersing fine particles, uniform cutting edges can be processed.

  Here, as described above, the cross-sectional shape in the plate thickness direction of the blade tip 11 of the flat blade-shaped cutting blade 1 is that the distance from the blade tip 17 to the connection portion 15 is different on the left and right with respect to the center line 21. In any of the methods (1) and (2), it is necessary to perform processing so that the cross-sectional shape in the plate thickness direction is different on the left and right.

  As an example of such processing, there is a method in which coating processing is performed on one surface of the blade tip 11 as shown in FIG. 9 until at least the final processing of the processing is performed. That is, as shown in FIG. 9, when the coating process is performed on one side and the coating 31 is formed, the hardness of the left and right surfaces of the blade tip 11 is different. For this reason, when processing is performed in this state, a difference occurs in the left and right processing amount (polishing amount) due to the hardness difference, so that processing can be performed so that the cross-sectional shape in the plate thickness direction is different on the left and right.

  Here, as a method of the film treatment, for example, a method of forming a film of sub μm to several μm by a sputtering method which is one kind of PVD (Physical Vapor Deposition).

  At this time, it is possible to perform masking on a surface that is not desired to be coated or to devise the arrangement of the cutting blade before coating (for example, on the opposite side of the target).

  Further, the type of coating is not particularly limited, and may be Ti-based or Fe-based, or non-metallic, as long as the hardness is lower than the material of the flat blade-shaped cutting blade 1.

  By coating such a film only on one side, for example, by processing with the above-mentioned abrasive solution, the tip of the blade tip can be processed into an asymmetric shape, and the degree of asymmetry (Y1 and Y2) is the film thickness of the film. Can be adjusted. The film is finally polished by processing and disappears.

  Further, the order of the coating treatment is not necessarily after the blade surfaces 13a and 13b are formed on both surfaces, and the coating treatment is performed after cutting only one surface of the material of the flat blade-shaped cutting blade 1, and the other remaining after that. The single-sided blade processing may be performed. Thus, by processing the flat blade-shaped cutting blade 1 subjected to the coating treatment on one surface in a solution having, for example, a hard material, the flat blade-shaped cutting blade having the above-described shape can be finished.

  The above is description of the processing method of the blade edge | tip part 7 of the flat blade-shaped cutting blade 1. FIG.

  Thus, according to the present embodiment, the blade edge portion 7 that is the cutting execution portion of the flat blade-shaped cutting blade 1 includes the left blade surface 9 a and the right blade surface 9 b that are inclined so as to approach each other from the left and right surfaces of the base 5. The intersection of two straight lines 13a, 13b formed so as to connect the left blade surface 9a and the right blade surface 9b, having a cutting edge tip 11 having a convex curved surface, along the left blade surface 9a and the right blade surface 9b. And the shortest distance of the blade tip 11 is not less than 1 μm and not more than 10 μm, the length of the blade tip 11 is different on the left and right with respect to the center line 21, and the difference is not less than 1 μm and not more than 20 μm, The interior angle of the intersection angle of the two straight lines along the left and right blade surfaces is not less than 4 degrees and not more than 60 degrees.

  Therefore, the flat blade-shaped cutting blade 1 satisfies both stable shape accuracy and cutting performance, and can suppress oblique cutting.

  Hereinafter, based on an Example, this invention is demonstrated in detail.

Example 1
A cutting test using the flat blade-shaped cutting blade 1 manufactured by the method of forming the blade tip 11 in a solution having abrasive grains is performed, and the effect of the shape of the blade tip 11 on the chipping property, wear resistance and cutting surface is examined. evaluated. The specific procedure is as follows.

<Processing of flat cutting blade 1>
First, a flat plate material made of cemented carbide FM10K made by Allied Material Co., Ltd. is prepared, with a length L in the blade direction of 100 mm, a length H in the short side of 20 mm, and a thickness T of 0.1 mm (see FIG. 2). Then, with existing technology using a grindstone, polishing is performed on one of the long sides so as to be bilaterally symmetric with respect to the cross section in the thickness direction, and the left blade surfaces 9a and 13a and the right blade surfaces 9b and 13b are formed. Formed.

  Thereafter, a TiN film having a thickness of 2 μm was formed on one side from the tip of the blade to a position of 1 mm by a sputtering method using Niden Anelva Corporation SPF-332.

  Next, as shown in FIG. 7, the blade edge of the flat blade-shaped cutting blade 1 was immersed in a solution 201 having a hard material, and the blade edge tip 11 was formed by reciprocating and sliding in the blade spanning direction for a certain period of time.

  As a solution having a hard material, polishing diamond slurry PC-1-W (Fsss particle size 1 μm) manufactured by Wada Trading Co., Ltd. was used, and PC-N100-W (particle size 0.1 μm) was used as a finish.

  Although not shown, the solution 201 (aqueous solution) is slid while stirring so as to have a uniform concentration so as not to affect the cutting edge processing, and the slide time is adjusted. A flat blade-shaped cutting blade 1 having a blade tip 11 shown in FIG. Here, the connection part 15 of FIG. 4 was a curve.

<Evaluation of flat blade-shaped cutting blade 1>
Next, the flat blade-shaped cutting blade 1 was evaluated according to the following procedure.

  First, a material to be cut was prepared.

  Here, as described above, the flat blade-shaped cutting blade 1 is mainly a cutting blade for a green sheet, but as an object to be cut, a mixture of metal powder and oil clay was prepared in order to perform an acceleration test. . This is because the product green sheet has a large difference in properties (mechanical strength such as shear resistance) for each product, and it is difficult to select a green sheet having typical characteristics, and also for simple evaluation. .

  The metal powder was a material corresponding to the ceramic powder in the green sheet, and the oil clay was regarded as a material corresponding to the binder in the green sheet.

  The specific material manufacturing method and cutting test procedure are as follows.

  First, W powder having an Fsss particle size of 1 μm was mixed with the Chubu Denki Kogyo Co., Ltd. oil-grown clay poppy so as to be uniform in a mortar at a weight ratio of 100: 20.

Next, this mixture was molded to a thickness of 1 mm at a press pressure of 10 kg / cm ² to obtain a workpiece.

  Next, as shown in FIG. 1, the flat blade-shaped cutting blade 1 was incorporated into a cutting device, and the material was continuously cut at a lowering speed of the cutting blade of 10 mm / second. Here, when the flat cutting blade 1 is raised, it can be moved in the horizontal direction so that the workpiece is not cut twice at the same horizontal position when continuously cutting. In addition, the dimension of the width direction of a to-be-cut object was 1 mm. A schematic diagram is shown in FIG.

  In order to completely cut the object to be cut, the lower part of the object to be cut must have a lower hardness than the object to be cut, and qualitative filter paper grade No. 1 manufactured by Toyo Filter Paper Co., Ltd. was laid.

  Table 1 shows the state of the blade edge before cutting and after the above cutting was performed 1000 times.

  In Table 1, the intersection of the two straight lines 13a and 13b along the left blade surface 9a and the right blade surface 9b and the shortest distance between the blade tip 11 is described as “X (μm)”.

  As confirmation of the evaluation, the presence / absence of chipping of the blade edge, the degree of wear of the blade edge, the state of the cut surface of the workpiece, and the presence / absence of oblique cutting were evaluated.

Specifically, the presence / absence of chipping is observed by enlarging the entire surface in the direction of the cutting edge, and “◯” indicates that no chipping is observed or there is a chipping of less than 5 μm. The case where there was a chip of 10 μm or more was judged as “x”. The observation was performed with an Olympus microscope STM6-LM at a magnification of 200 times.

  Further, the degree of wear of the blade edge is “◯” when the distance of H1 in FIG. 2 is shortened by 5 μm or less compared to before the start of cutting with the microscope, “△”, and when “5 μm is shortened by 10 μm or less” The case where it shortened exceeding 10 micrometers was judged as "x".

  The state of the cut surface of the cut product is also observed with a microscope. When the scratch on the 1000th cut surface is scratched with a width of less than 5 μm, “◯”, and when the scratch of 5 μm or more and less than 10 μm is seen, “△ “If the scratch of 10 μm or more was observed, it was judged as“ x ”.

  In addition, the evaluation of the presence or absence of oblique cutting was performed by observing the cut surface of the article to be cut having a thickness of 1 mm and a cutting width of 2 mm with an optical microscope after the cutting was performed, and confirmed whether or not the cutting was performed vertically. When the angle of the cut surface of the workpiece is 89 to 90 degrees, “◎”, less than 89 degrees, “greater than 88 degrees”, less than 88 degrees, less than 87 degrees “△”, less than 87 degrees “ × ”.

  As is apparent from Table 1, samples having the shortest distance X of 1 to 10 μm and the absolute value of Y1-Y2 of 1 μm or more and 20 μm or less (sample Nos. Examples 1 to 8, 25 to 52) have chipping on the cutting edge. The degree of wear of the blade edge, the state of the cut surface of the workpiece, and the oblique cutting were all evaluated as “Δ”, “◯”, or “◎”.

  On the other hand, samples (sample Nos. Comparative Examples 1 and 2 and 6 to 9) whose shortest distance X is out of this range are either the presence or absence of chipping of the blade edge, the degree of wear of the blade edge, or the state of the cut surface of the workpiece. (Or all) was rated “x”.

  As for the oblique cutting, the larger the cutting edge angle, the larger the oblique cutting. In particular, for the symmetrical blades (Comparative Examples 1, 6, and 8), Comparative Example 1 having a cutting edge angle of 4 degrees is an oblique cutting. Although the state of “○” was “◯”, Comparative Example 6 with a blade edge angle of 30 degrees was “Δ”, and Comparative Example 8 with a blade edge angle of 60 degrees was “X”, which was clearly oblique cut.

  On the other hand, in Comparative Example 3 where the blade edge angle was 3 degrees, the presence or absence of chipping of the blade edge, the degree of wear of the blade edge, and the state of the cut surface of the workpiece were all “x”. In Comparative Example 10 of 65 degrees, the degree of wear of the blade edge, the state of the cut surface of the workpiece, and the oblique cutting state were “x”.

(Example 2)
In Example 2, as a process for forming the blade tip 11, the blade tip 11 was formed using a method of forming the blade tip 11 using a solid material, and a cutting test was performed. The specific procedure is as follows.

  First, a plate material similar to that of Example 1 is polished by an existing technique using a grindstone so as to be symmetric with respect to a cross section in the thickness direction, and left blade surfaces 9a and 13a and a right blade surface 9b. , 13b was formed.

  Thereafter, a TiN film having a thickness of 2 μm was formed on one side from the tip of the blade tip to a position of about 1 mm by sputtering under the same conditions as in Example 1.

Next, as a solid material used for cutting edge processing, Chubu Denki Kogyo Co., Ltd. oil clay poppy, F3 grade titanium oxide powder made by Showa Denko Co., Ltd. in a mortar with a weight ratio of 100: 50 What was mixed so that it might become uniform was prepared. This mixture was molded to a thickness of 1 mm at a press pressure of 10 kg / cm ² .

Here, the specific surface area BET (Brunauer, Emmet and Teller) value of titanium oxide is 36 m ² / g, and the primary particles are observed by scanning electron microscope observation using Hitachi High-Technologies Field Emission Scanning Electron Microscope S-420. Was less than 0.1 μm.

  With this solid material to be cut, a flat blade-shaped cutting blade 1 was incorporated into a cutting apparatus as shown in FIG. 1, and the cutting blade was continuously cut at a descending speed of 5 mm / second. Here, when cutting continuously, each time the flat blade-shaped cutting blade 1 is raised, the workpiece can be moved in the horizontal direction so that the workpiece is not cut twice at the same horizontal position (see FIG. 8). . The cutting edge number 11 was adjusted to adjust the blade tip 11 to the shape shown in Table 2.

  Here, the connection part 15 of FIG. 4 was a curve.

  Next, with the obtained flat blade-shaped cutting blade 1, the same material as in Example 1 was cut in the same way, and as in Example 1, the presence or absence of chipping of the blade edge, the degree of wear of the blade edge, the object to be cut The state of the cut surface and the presence or absence of oblique cutting were evaluated.

The results are shown in Table 2.

  As is apparent from Table 2, samples with the shortest distance X of 1 to 10 μm and the absolute value of Y1-Y2 of 1 μm or more and 20 μm or less (sample Nos. Examples 9 to 24) are subject to the presence or absence of chipping of the blade edge and wear of the blade edge. The degree, the state of the cut surface of the workpiece, and the oblique cutting were all evaluated as “◯” or more, and the same result as in Example 1 was obtained.

(Example 3)
Sample No. 1 of Example 1 The flat blade-shaped cutting blade 1 similar to 1-8 was produced, and the cutting test was performed with the size in the width direction of the workpiece being 0.5 mm.

The results are shown in Table 3.

  As can be seen from Table 3, even with the same blade as in Example 1, it can be seen that the evaluation of oblique cutting tends to be slightly worse when the product size is smaller. From this result, it was found that small-size products are more likely to be obliquely cut.

  As mentioned above, although this invention was demonstrated based on embodiment and an Example, this invention is not limited to above-described embodiment.

  It is natural for those skilled in the art to come up with various modifications and improvements within the scope of the present invention, and it is understood that these also belong to the scope of the present invention.

1: Flat blade-shaped cutting blade 3: Cutting device fixing portion 5: Base portion 5a: Fixed portion 5b: Connection portion 7: Blade edge portion 9a: Left blade surface 9b: Right blade surface 11: Cutting edge tip 15: Connection portion 21: Center Line 31: Film 100: Object 201: Solution 203: Container 205: Solid X: Shortest distance Y1: Distance Y2: Distance θ: Interior angle

Claims (6)

A flat base, and
Left and right blade surfaces inclined so as to approach each other from both surfaces of the base, and
A cutting edge tip formed to connect the left and right blade surfaces, and having a convex curved surface;
Have
In the cross-sectional shape in the plate thickness direction, the shortest distance between the intersection of two straight lines along the left and right blade surfaces and the tip of the blade edge is 1 μm or more and 10 μm or less,
And the length of the tip is different on the left and right with respect to the center line of the base, and the difference is 1 μm or more and 20 μm or less,
Further, the flat blade-shaped cutting blade is characterized in that an inner angle of an intersection angle between two straight lines along the left and right blade surfaces is 4 degrees or more and 60 degrees or less.   2. The flat blade-shaped cutting blade according to claim 1, wherein the length of the tip of the cutting edge is different on the left and right blade surfaces with respect to the center line of the base, and the difference is 2 μm or more and 10 μm or less.   The flat blade-shaped cutting blade according to claim 1 or 2, wherein at least the cross-sectional shape of the connection portion between the left and right blade surfaces and the tip of the blade edge is a curve.   The flat blade according to any one of claims 1 to 3, wherein a shortest distance between an intersection of two straight lines along the left and right blade surfaces and a tip of the blade tip is 1.5 µm or more and 5 µm or less. Cutting blade.   The flat blade-shaped cutting blade according to any one of claims 1 to 4, wherein an internal angle of an intersection angle between two straight lines along the left and right blade surfaces is 10 degrees or more and 30 degrees or less. .   A green sheet cutting blade comprising the flat blade-shaped cutting blade according to any one of claims 1 to 5.

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