Curved saw

Abstract

To provide a new curved saw that combines the advantages of the prismatic teeth themselves and the advantages of a curved saw by applying prismatic teeth to a curved saw. This is a curved saw in which the sawtooth is arranged in the longitudinal direction of the saw body 1 and the cutting edge line L of the arranged sawtooth is curved from the base end to the tip end of the saw body 1, and prismatic teeth 3 are used as the arranged sawtooth, with a cutting blade 3b formed at the tip of each prismatic tooth 3 and a cutting blade 3c formed on the side column edge located closest to the base end of the prismatic tooth 3, and all of the arranged prismatic teeth 3 are formed to have the same rise angle A, so that the dimension of the gap S formed between each prismatic tooth 3 is constant in the rise direction of the teeth.

Description

[Technical field]

[0001] The present invention relates to a curved saw having a curved cutting edge line of a saw blade. [Background technology]

[0002] Conventionally, hand saws are generally straight saws, in which the cutting edge of the saw blade is straight, and curved saws, in which the cutting edge of the saw blade is curved, have also been provided. A general drawback of the straight saw is that the actual cutting edge of the tip of the blade region tends to decrease during sawing, and the saw tends to fall off the workpiece. The curved saw is a tool that overcomes the drawbacks of the straight saw. In the case of a curved saw, the cutting edge line is curved, which increases the actual degree to which the tip of the blade region bites into the workpiece, eliminating the risk of the blade falling out due to insufficient penetration. On the other hand, in the case of curved saws, the cutting edge of the blade region may bite into the workpiece excessively, causing the blade to jam. Incidentally, the present inventors have internationally disclosed a new sawtooth shape, so-called "prismatic teeth," such as "triangular prismatic teeth," on December 10, 2015 in WO2015 / 186204 A1. The "prismatic teeth" are a novel saw blade shape that is completely different from the so-called "triangular teeth" that were used earlier. Regarding the technology relating to this "prismatic tooth", there have been no related inventions by anyone other than the present inventor that have been published internationally. Furthermore, as far as the applicant knows, there are no actual saws currently available on the market that are equipped with these "prismatic teeth." The applicant has invented and completed a new curve saw equipped with "prismatic teeth". This product will be sold before any other product in the world after the filing of the patent application. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. WO2015 / 186204 [Patent Document 2] International Publication No. WO2017 / 033305 [Patent Document 3] JP 2005-295945 A Summary of the Invention [Problem to be solved by the invention]

[0004] As mentioned above, the above Patent Document 1 is an invention that was internationally published in 2015. Whereas the sawtooth shape before that was so-called "triangular teeth," the invention of Patent Document 1 uses "prismatic teeth," such as "triangular prism teeth" and "trapezoidal prism teeth" (reference numbers 30, 40, etc.). In addition, "inclined triangular prism teeth" (reference number 50) are also disclosed as triangular prism teeth (Figure 7). However, these "prismatic teeth" in Patent Document 1 are all intended for application to a typical straight saw (a saw with a straight cutting edge line) (FIG. 1 in Patent Document 1). The above-mentioned Patent Document 2 is also an invention previously provided by the present inventor. It discloses a straight saw in which, as saw teeth, in addition to cross-cutting teeth X made of triangular or trapezoidal prismatic teeth, longitudinal cutting teeth Y made of parallelogram prismatic teeth are inserted at various points in the tooth row. In other words, the rectangular prism teeth such as triangular prism teeth, trapezoidal prism teeth, and parallelogram prism teeth in Patent Document 2 are also intended to be applied to straight saws, just like in Patent Document 1 (Figures 1 and 10). The above-mentioned Patent Document 3 discloses a conventional curve saw that uses "triangular teeth" that have been generally used in the past as saw teeth (reference numeral 2). The curved saw of Patent Document 3 discloses that the intersection angle (symbol α) between the cutting edge (symbol 3) and the cutting edge line (symbol 5) is changed so that it is larger on the base end side and smaller on the tip end side. However, as already mentioned, the curved saw of Patent Document 3 has saw teeth that are all arranged as "triangular teeth" (reference numeral 2), and the curved saw is invented on the premise of these "triangular teeth." Patent Document 3 discloses a curved saw in which the triangular shape of the triangular teeth (reference symbol 2) changes successively from the base end to the tip end. However, manufacturing a curved saw in which the shape of each tooth in the tooth row changes successively is disadvantageous in that it is not easy to shape the teeth, and it takes a lot of time and costs money.

[0005] The inventor came up with the idea of ​​applying prismatic teeth such as triangular prism teeth or square prism teeth to a curved saw, instead of the conventional curved saw that uses triangular teeth. The inventor then came up with the idea of ​​applying these prismatic teeth to a curved saw, and after repeated research and trial production to find a new, preferable and effective structure for this application, he was able to complete the present invention. An object of the present invention is to provide a new curved saw that combines the advantages of both the prismatic teeth themselves and the advantages of a curved saw by applying prismatic teeth to a curved saw. [Means for solving the problem]

[0006] In order to achieve the above object, the curved saw of the present invention is a curved saw in which saw teeth are arranged in the longitudinal direction of a saw body 1 and a cutting edge line L formed by the arranged saw teeth is curved from the base end side to the tip end side of the saw body 1, The saw teeth arranged on the curved saw are prismatic teeth 3 consisting of triangular prism teeth or quadrangular prism teeth, Each prismatic tooth 3 is arranged flush with the front and back sides of the saw body 1 while alternating in direction. With sides A rectangular column portion 3a is provided, and a scraping blade 3b having a width extending across the front and back of the saw body 1 is formed at the tip of the rectangular column portion 3a, and a cutting blade 3c is formed on the side column edge located at the most base end side of each side column edge constituting the rectangular column portion 3a. Each of the arranged prismatic teeth 3 is From the longitudinal side edge surface 1c of the blade region Z of the saw body 1By forming the rising angle A to be the same for all teeth, the size of the gap S formed between each prismatic tooth 3 is constant in the tooth rising direction. death, Furthermore Each of the rectangular prism teeth 3 arranged on the saw body 1 is formed as an inclined rectangular prism tooth 32 inclined at the same rising angle A from the saw body 1, and the rising angle A of each of the inclined rectangular prism teeth 32 is configured to match an angle of incidence B of the cutting blade 32C with respect to the cutting edge line L that is preset to an angle less than 90 degrees. No. 1 It is characterized by the following: The curve saw of the present invention is No. 1 In addition to the above features, the inclined columnar tooth 32 has a rise angle A of 70 degrees or more and less than 90 degrees, the inclined columnar tooth 32 has a curvature increase angle C of 20 degrees or more and 40 degrees or less, which is increased by curving the blade region Z from the base end Z1 to the tip end Z2, and the sum angle D of the rise angle A and the curvature increase angle C is 120 degrees or less at the tip end Z2 of the blade region Z. Second It is characterized by the following: The curve saw of the present invention is Second In addition to the above features, two of the three angle conditions consisting of the value of the rising angle A, the value of the curvature increase angle C, and the value of the additional angle D are preset, and one of the two dimensional conditions consisting of the value of the blade length W of the saw body 1 and the value of the curvature radius R of the cutting edge line L is preset, and the remaining one angle condition and one dimensional condition are calculated and set from the two preset angle conditions and one dimensional condition. Third It is characterized by the following: The curve saw of the present invention is Third In addition to the above features, the value of the rising angle A of the inclined columnar teeth 32, the value of the curvature increase angle C, and the blade length W of the saw body 1 are preset, and the value of the addition angle D and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the rising angle A, the value of the curvature increase angle C, and the value of the blade length W. Fourth It is characterized by the following: The curve saw of the present invention is ThirdIn addition to the above features, the value of the rising angle A of the inclined rectangular columnar tooth 32, the value of the additional angle D, and the value of the curvature radius R of the cutting edge line L are preset, and the value of the rising angle A, the value of the additional angle D, and the value of the curvature radius R of the cutting edge line L are calculated based on the value of the rising angle A, the value of the additional angle D, and the value of the curvature radius R of the cutting edge line L. 、 The value of the curved increase angle C and the blade length W of the saw body 1 are calculated and set. Fifth It is characterized by the following: The curve saw of the present invention is Third In addition to the above features, the value of the rising angle A of the inclined columnar teeth 32, the value of the additional angle D, and the value of the blade length W of the saw body 1 are preset, and the value of the rising angle A, the value of the additional angle D, and the value of the blade length W are calculated based on the value of the rising angle A, the value of the additional angle D, and the value of the blade length W. 、 The value of the curvature increase angle C and the value of the curvature radius R of the cutting edge line L are calculated and set. Sixth It is characterized by the following: The curve saw of the present invention is Third In addition to the above features, the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W of the saw blade 1 are preset, and the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W are calculated based on the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W. 、 The value of the rising angle A and the value of the curvature radius R of the cutting edge line L are calculated and set. Seventh It is characterized by the following: The curve saw of the present invention is Third In addition to the above features, the value of the curvature increase angle C, the value of the additional angle D, and the value of the curvature radius R of the cutting edge line L are preset, and the value of the curvature increase angle C, the value of the additional angle D, and the value of the curvature radius R of the cutting edge line L are calculated from the value of the curvature increase angle C, the value of the additional angle D, and the value of the curvature radius R of the cutting edge line L. 、 The rise angle A and the blade length W are calculated and set. Eighth It is characterized by the following: The curve saw of the present invention is 1st~8thIn addition to any one of the above features, the arrangement of the inclined rectangular prismatic teeth 32 is configured to be any one of an arrangement of inclined triangular prismatic teeth 321, an arrangement of inclined trapezoidal prismatic teeth 322, an arrangement of inclined triangular prismatic teeth 321 interspersed with inclined parallelogram prismatic teeth 323, and an arrangement of inclined trapezoidal prismatic teeth 322 interspersed with inclined parallelogram prismatic teeth 323. 9th It is characterized by the following: Effect of the Invention

[0007] According to the curved saw of claim 1, the saw teeth arranged on the saw body 1 are not triangular teeth as in the conventional method, but are prismatic teeth 3 consisting of triangular prism teeth or square prism teeth instead. The arranged prismatic teeth 3 form a scraping blade 3b at the tip of the prismatic portion 3a, the width of which extends across the front and back of the saw body 1. In addition, a cutting blade 3c is formed on the side pillar edge that is located closest to the base end of each side pillar edge that constitutes the prismatic portion 3a, making it a saw (drawing saw). The cutting operation is performed by cutting into the workpiece G with the cutting blade 3c and scraping it with the scraping blade 3b. According to the curved saw of claim 1, the effect of the conventional triangular tooth curved saw is maintained by curving the blade length region Z of the saw body 1, and further, by applying new prismatic teeth 3 in place of the triangular teeth that have been used conventionally, the following new functional effects can be added. That is, according to the curved saw of claim 1, the prismatic teeth 3 are formed with cutting edges 3b having a width that extends across the front and back of the saw body 1, so the cutting edge length of the cutting edges 3b can be made sufficiently larger than that of conventional triangular tooth cutting edges. Hand saw It is possible to provide a curved saw that greatly improves the amount and width of material that can be removed in one stroke, thereby greatly improving its sharpness. Furthermore, according to the curved saw of claim 1, the gaps S between the prismatic teeth 3 are configured to be constant in the direction of the tooth rise. This eliminates the problem of chip clogging caused by V-shaped gaps that occurred with conventional triangular teeth. In other words, it is possible to provide a curved saw that can efficiently discharge chips. Furthermore, according to the curved saw of claim 1, unlike triangular teeth whose tooth bases spread out in the longitudinal direction, the prismatic teeth 3 do not spread out in the longitudinal direction. This makes it possible to arrange many prismatic teeth 3 more densely in the longitudinal direction. This makes it possible to provide a curved saw with improved sharpness and cutting efficiency than ever before, thanks to the densely arranged triangular prism teeth 3.

[0008] In particular, claim 1 According to the curve saw described in ,saw Each of the inclined prismatic teeth 32 arranged on the body 1 is formed as an inclined prismatic tooth 32 that is inclined at the same rising angle A from the saw body 1. In other words, there is no need to individually change or adjust the tooth shape or rising angle A of each inclined prismatic tooth 32. This makes it possible to provide a curved saw with a very simple set of inclination angles. Also Claim 1 According to the curved saw described in the above, if there is a preferred incidence angle B of the cutting blade 3c of the prismatic tooth 3 with respect to the cutting edge line L, the preferred incidence angle B of the cutting blade 3c can be formed as the rising angle A of the inclined prismatic tooth 32, thereby forming a saw with the rising angle A of the inclined prismatic tooth 32 as it is as the preferred incidence angle B of the cutting blade 32c of the inclined prismatic tooth 32. Therefore, the cutting angle at the base end Z1 of the blade region Z of the saw with respect to the workpiece G can be simply and easily adjusted to the incidence angle B of the cutting blade 32c, i.e., the rising angle A of the inclined prismatic tooth 32, to form a curved saw. Also Claim 1 According to the curved saw described in the above, the rise angle A of the inclined prismatic teeth 32 is configured to match a preset angle less than 90 degrees as the incident angle B of the cutting blade 32c with respect to the cutting edge line L. That is, the inclined prismatic teeth 32 are formed so that the rise angle A matches a preset preferred incident angle B. This makes it possible to smoothly start the sawing operation starting from the base end portion Z1 of the blade region Z with a cutting angle less than 90 degrees.

[0009] Claim 2 According to the curve saw described in Claim 1In addition to the effects of the configuration described above, the rise angle A of the inclined columnar teeth 32 from the saw body 1 is set to an angle of 70 degrees or more and less than 90 degrees. By setting the rise angle A to an angle of 70 degrees or more and less than 90 degrees, the incidence angle B of the cutting blade 32c with respect to the cutting edge line L is also set to the same angle of 70 degrees or more and less than 90 degrees. Therefore, in the sawing operation starting from the base end portion Z1 of the blade length region Z of the saw body 1, the cutting angle of the cutting blade 32c into the workpiece G can also be set to an angle of 70 degrees or more and less than 90 degrees. This makes it possible to make it difficult for the cutting blade 32c to get caught in the workpiece G when the cutting operation starts, and allows the sawing operation to start smoothly. If the rise angle A is less than 70 degrees, the angle at which the cutting blade 32c cuts into the workpiece G at the base end Z1 of the blade region Z also tends to be too low, less than 70 degrees. Therefore, although the cutting blade 32c is prevented from biting into the workpiece G at the base end Z1 of the blade region, the cutting by the cutting blade 32c at the base end Z1 of the blade region tends to be insufficient. On the other hand, when the rise angle A is 90 degrees or more, the cutting angle of the cutting blade 32c at the base end Z1 of the blade region into the workpiece G at the beginning of the sawing operation tends to be too high. Therefore, the cutting blade 32c is more likely to bite into the workpiece G at the base end Z1 of the blade region. Also Claim 2 According to the curved saw described in the above, the angle C of curvature of the inclined columnar teeth 32, which increases as the blade region Z curves from the base end Z1 to the tip end Z2, is set to an angle of 20 degrees or more and 40 degrees or less. When the blade region Z is curved, the actual inclination of the cutting blade 32c of each arranged inclined columnar tooth 32 increases from the base end Z1 to the tip end Z2 of the blade region Z. If the increased angle due to this curvature is defined as the curve increase angle C, the larger the curve increase angle C, the larger the cutting angle of the cutting blade 32c at the tip end Z2 into the workpiece G. As the cutting angle increases, the cutting effect improves, but the cutting blade 32c is more likely to bite into the workpiece G. By setting the curvature increase angle C to be greater than or equal to 20 degrees and less than or equal to 40 degrees, the cutting action of the cutting blade 32c, which begins at the base end Z1 of the blade region Z, can be effectively increased toward the tip end Z2 of the blade region Z, and biting due to an excessive increase in the cutting angle of the cutting blade 32c can be effectively prevented. If the curvature increase angle C is less than 20 degrees, a good increase in the cutting action from the base end Z1 to the tip end Z2 of the blade region Z cannot be expected compared to a rise angle at the base end Z1 of the blade region of 70 degrees or more and less than 90 degrees. On the other hand, if the curvature increase angle C exceeds 40 degrees, the cutting edge 32c is more likely to bite at the tip end Z2 of the blade region. Also Claim 2 According to the curve saw described in the above, the sum angle D of the rise angle A and the curvature increase angle C is configured to be an angle of 120 degrees or less at the tip Z2 of the blade region. The sum angle D can be said to be the actual inclination angle of the cutting edge 32c of the inclined columnar tooth 32 at the tip Z2 of the blade region. If the sum angle D of the inclined columnar tooth 32 at the tip Z2 exceeds 120 degrees, the cutting edge 32c is likely to get caught.

[0010] Claim 3 According to the curve saw described in Claim 2 In addition to the effects of the configuration described above, two of the three angle conditions consisting of the value of the rise angle A, the value of the curvature increase angle C, and the value of the additional angle D are preset. Also, one of the two dimensional conditions consisting of the value of the blade length W of the saw body 1 and the value of the curvature radius R of the cutting edge line L is preset. Then, the remaining one angle condition and one dimensional condition are calculated and set from the two angle conditions and one dimensional condition preset. By using the values ​​of the three angle conditions and the two dimensional conditions obtained in this manner, it is possible to provide a curved saw having prismatic teeth 3 with various rise angles A, various blade lengths W, and various radii of curvature R with good cutting action and good jamming prevention action.

[0011] Claim 4 According to the curve saw described in Claim 3In addition to the advantageous effects of the configuration described above, the value of the rise angle A of the inclined columnar teeth 32, the value of the curvature increase angle C, and the blade length W of the saw blade 1 are preset. Then, the value of the addition angle D and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the rise angle A, the value of the curvature increase angle C, and the value of the blade length W. Therefore, by determining in advance the values ​​of the rise angle A, the curvature increase angle C, and the blade length W, it is possible to calculate the value of the added angle D and the value of the curvature radius R of the cutting edge line L. Then, with the obtained values ​​of these five conditions, it is possible to easily provide a curved saw with a specified rise angle A, a specified blade length W, and a specified curvature increase angle C, which has good cutting action and good jamming prevention action.

[0012] Claim 5 According to the curve saw described in Claim 3 In addition to the advantageous effects of the configuration described above, the value of the rise angle A of the inclined columnar tooth 32, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L are preset. Then, the value of the curvature increase angle C and the value of the blade length W are calculated and set from the value of the rise angle A, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L. Therefore, by determining in advance the values ​​of the rise angle A, the addition angle D, and the radius of curvature R of the cutting edge line L, it is possible to calculate the value of the increased curvature angle C and the blade length W. Using the obtained values ​​of these five conditions, it is possible to easily provide a curved saw with a specified rise angle A, a specified addition angle D, and a specified radius of curvature R, which has good cutting performance and good anti-jamming performance.

[0013] Claim 6 According to the curve saw described in Claim 3 In addition to the advantageous effects of the configuration described above, the value of the rise angle A, the value of the additional angle D, and the value of the blade length W of the inclined columnar tooth 32 are preset. Then, the value of the curvature increase angle C and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the rise angle A, the value of the additional angle D, and the value of the blade length W. Therefore, by determining in advance the values ​​of the rise angle A, the addition angle D, and the blade length W, it is possible to calculate the value of the curvature increase angle C and the value of the curvature radius R of the cutting edge line L. Then, with the obtained values ​​of these five conditions, it is possible to easily provide a curved saw with a specified rise angle A, a specified addition angle D, and a specified blade length W, which has good cutting action and good anti-jamming action.

[0014] Claim 7 According to the curve saw described in Claim 3 In addition to the advantageous effects of the configuration described above, the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W are preset. The value of the rise angle A and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W. Therefore, by determining in advance the values ​​of the curvature increase angle C, the addition angle D, and the blade length W, it is possible to calculate the value of the rise angle A and the value of the curvature radius R of the cutting edge line L. Then, with the obtained values ​​of these five conditions, it is possible to easily provide a curved saw having a predetermined curvature increase angle C, a predetermined addition angle D, and a predetermined blade length W, with good cutting performance and good jamming prevention performance.

[0015] Claim 8 According to the curve saw described in Claim 3 In addition to the advantageous effects of the configuration described above, the value of the curvature increase angle C, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L are set in advance. The value of the rise angle A and the value of the blade length W are calculated and set from the value of the curvature increase angle C, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L. Therefore, by determining the values ​​of the additional angle C of the curve, the additional angle D, and the curvature radius R of the cutting edge line L in advance, the value of the rising angle A and Blade length WThe values ​​of can be obtained by calculation. Using the obtained values ​​of these five conditions, a curve saw having a predetermined curve increase angle C, a predetermined addition angle D, and a predetermined curvature radius R can be easily provided with good cutting performance and good jamming prevention performance.

[0016] Claim 9 According to the curve saw described in Claims 1 to 8 In addition to the advantageous effects of any of the configurations described above, the arrangement of the inclined rectangular prismatic teeth 32 is configured to be either an arrangement of inclined triangular prismatic teeth 321, or an arrangement of inclined trapezoidal prismatic teeth 322, or an arrangement in which inclined parallelogram prismatic teeth 323 are mixed in between an arrangement of inclined triangular prismatic teeth 321, or an arrangement in which inclined parallelogram prismatic teeth 323 are mixed in between an arrangement of inclined trapezoidal prismatic teeth 322. When arranging the inclined triangular columnar teeth 321 or the inclined trapezoidal columnar teeth 322 alone, it is only necessary to arrange teeth of the same shape and the same inclination, so that a very simple curved saw can be easily manufactured. Furthermore, when the inclined parallelogram prismatic teeth 323 are mixed in between the array of inclined triangular prismatic teeth 321, or when the inclined parallelogram prismatic teeth 323 are mixed in between the array of inclined trapezoidal prismatic teeth 322, in addition to the preferable cross-cutting action of the inclined triangular prismatic teeth 321 and the inclined trapezoidal prismatic teeth 322, the preferable vertical cutting action and chip discharge action of the inclined parallelogram prismatic teeth 323 can be added. [Brief description of the drawings]

[0017] [Figure 1] 1 is an overall perspective view of a curved saw according to an embodiment of the present invention; [Diagram 2] 2 is an enlarged view of a base end Z1 of a blade region Z of a curved saw according to an embodiment of the present invention. FIG. [Diagram 3] 2 is an enlarged view of a tip Z2 of a blade region Z of a curved saw according to an embodiment of the present invention. FIG. [Figure 4]FIG. 1 is a diagram illustrating a vertical triangular prism tooth 311 used in a curved saw according to an embodiment of the present invention, where (A) is a plan view, (B) is an oblique view from the front, and (C) is a diagram showing the tooth rise angle A. [Diagram 5] FIG. 13 is a diagram illustrating vertical trapezoidal columnar teeth 312 used in a curved saw according to an embodiment of the present invention, where (A) is a plan view, (B) is a perspective view from the front, and (C) is a diagram showing the tooth rise angle A. [Figure 6] FIG. 1 is a diagram illustrating an inclined triangular prism tooth 321 used in a curved saw according to an embodiment of the present invention, where (A) is a plan view, (B) is an oblique view from the front, and (C) is a diagram showing the tooth rise angle A. [Figure 7] FIG. 13 is a diagram illustrating an inclined trapezoidal columnar tooth 322 used in a curved saw according to an embodiment of the present invention, where (A) is a plan view, (B) is an oblique view from the front, and (C) is a diagram showing the tooth rise angle A. [Figure 8] FIG. 13 is a diagram illustrating an example of combining vertical parallelogram columnar teeth 313 with an arrangement of vertical trapezoidal columnar teeth 312 used in a curved saw according to an embodiment of the present invention, where (A) is a plan view, (B) is an oblique view from the front, and (C) is a diagram showing the tooth rise angle A. [Figure 9] FIG. 13 is a diagram illustrating an example of combining inclined parallelogram-shaped tooth 323 with an array of inclined trapezoidal-shaped tooth 322 used in a curved saw according to an embodiment of the present invention, where (A) is a plan view, (B) is an oblique view from the front, and (C) is a diagram showing the tooth rise angle A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A curve saw according to an embodiment of the present invention will be described with reference to the following drawings. First, with reference to FIGS. 1 to 3, the curved saw includes a saw body 1 and a grip body 2. The grip body 2 is not particularly limited in shape, whether it is foldable, etc. However, the grip body 2 is also curved. It is preferable to make the curvature of the grip body 2 equal to or greater than that of the saw body 1, so that cutting work can be easily performed. The saw body 1 is a curved saw having an overall curved shape. The saw blade 1 is provided with a blade region Z that is curved from its base end to its tip end. The blade region Z has a plurality of prismatic teeth 3 arranged from a base end Z1 to a tip end Z2 of the blade region Z. The cutting edge line L of the prismatic teeth 3 arranged in the cutting edge region Z can be configured as a part of the circumference of a circle with a predetermined radius of curvature. Strictly speaking, a curved saw can be defined as a saw in which the cutting edge line L is curved. The shape of the curve of the cutting edge line L of the curved saw is such that the center of curvature K of the curve is on the ventral side of the saw body 1. In accordance with the curvature of the cutting edge line L, the saw body 1 is usually curved over its entire length.

[0019] The first embodiment of the present invention is a curved saw in which prismatic teeth 3 are arranged in a blade region Z provided on the ventral side of the saw body 1, and the cutting edge line L formed by the arranged prismatic teeth 3 is part of a circumference having a predetermined radius of curvature R. The cutting edge region Z is formed as a part of a circumferential region having the same center of curvature K as the center of curvature K of the cutting edge line L.

[0020] 4 to 9, the prismatic teeth 3 may be triangular prism teeth or quadrangular prism teeth. More specifically, the prismatic teeth 3 may be vertical prismatic teeth 31 and inclined prismatic teeth 32 . Furthermore, as the vertical prismatic teeth 31, vertical triangular prismatic teeth 311 shown in FIG. 4, vertical trapezoidal prismatic teeth 312 shown in FIG. 5, and vertical parallelogram prismatic teeth 313 shown in a part of FIG. 8 can be used. As the inclined rectangular columnar teeth 32, inclined triangular columnar teeth 321 shown in FIG. 6, inclined trapezoidal columnar teeth 322 shown in FIG. 7, and inclined parallelogram columnar teeth 323 shown in part of FIG. 9 can be used. Here, "vertical" means that the rising angle A from the saw body 1 is vertical. Moreover, the inclination means that the rising angle A from the saw body 1 is in an inclined state. The vertical parallelogram prismatic teeth 313 can be preferably used as teeth added at various points in the arrangement of the vertical triangular prismatic teeth 311 and the vertical trapezoidal prismatic teeth 312, and the inclined parallelogram prismatic teeth 323 can be preferably used as teeth added at various points in the arrangement of the inclined triangular prismatic teeth 321 and the inclined trapezoidal prismatic teeth 322.

[0021] Each of the prismatic teeth 3 (31, 32, 311, 312, 313, 321, 322, 323) rises flush with the front and back sides 1a and 1b of the saw body 1 while alternating in direction. With sides A rectangular column portion 3a (31a, 32a, 311a, 312a, 313a, 321a, 322a, 323a) is provided, a scraping blade 3b (31b, 32b, 311b, 312b, 313b, 321b, 322b, 323b) having a width extending across the front and back of the saw body 1 is formed at the tip of the rectangular column portion 3a, and a cutting blade 3c (31c, 32c, 311c, 312c, 313c, 321c, 322c, 323c) is formed on the side column side that is located closest to the base end of the saw body 1 among the side column sides that constitute the rectangular column portion 3a, Each of the arranged prismatic teeth 3 has a rise angle A, That is, the rising angle A from the longitudinal side edge surface 1c of the blade region Z of the saw body 1, By forming all of the prismatic teeth 3 at the same angle, the dimensions of the gaps S formed between each of the prismatic teeth 3 are all constant in the direction in which the teeth rise.

[0022] As described above, according to the curved saw of the first embodiment of the present invention, the prismatic teeth 3 are formed with cutting edges 3b that have a width that spans the front and back of the saw body 1, so the cutting edge length of the cutting edges 3b can be made sufficiently larger than that of conventional triangular teeth. This greatly improves the amount and width of cutting that can be achieved in one sawing stroke, and greatly improves the sharpness of the saw. Furthermore, the gaps S between each of the rectangular columnar teeth 3 are configured to be constant in the direction of tooth rise, eliminating the problem of chip clogging caused by the V-shaped gaps of conventional triangular teeth, enabling smooth chip removal. Also, unlike triangular teeth, the base of the prismatic teeth 3 does not spread out in the longitudinal direction, making it possible to arrange the prismatic teeth 3 more closely together for efficient cutting.

[0023] Referring to FIG. 4, the vertical triangular prism teeth 311 rise flush with the front and back side surfaces 1a and 1b of the saw body 1 while alternately changing their orientation. With sides It has a vertical prism portion 311a. At the tip of the vertical prism portion 311a, a scraping blade 311b is formed with a width that spans the front and back of the saw body 1. In addition, of the side pillar sides that make up the vertical prism portion 311a, a cutting blade 311c is formed on the side pillar side that is located closest to the base end of the saw body 1. The arranged vertical triangular prism teeth 311 are all formed so that the rising angle A from the longitudinal side edge surface 1c of the saw body 1 is the same angle of 90 degrees. More precisely, the rising angle A from the longitudinal side edge surface 1c of the saw body 1 is the rising angle A from the longitudinal side edge surface 1c of the cutting edge region Z of the saw body 1.

[0024] 5, the vertical trapezoidal columnar teeth 312 have vertical prismatic portions 312a that rise flush from the front and back side surfaces 1a, 1b of the saw body 1 while alternating in direction. A cutting blade 312b having a width that spans the front and back of the saw body 1 is formed at the tip of the vertical prismatic portion 312a. A cutting blade 312c is formed on the side pillar side that is located closest to the base end of the saw body 1 among the side pillar sides that constitute the vertical prismatic portion 312a. Other than that, it is the same as the vertical triangular columnar teeth 311, and the rise angle A from the longitudinal side edge surface 1c of the saw body 1 is formed at the same angle of 90 degrees, and the size of the gap S between each vertical trapezoidal columnar tooth 312 is constant in the tooth rise direction.

[0025] Referring to FIG. 6, the inclined triangular prism teeth 321 rise flush with the front and back side surfaces 1a and 1b of the saw body 1 while alternately changing their orientation. With sidesThe saw blade 1 has an inclined rectangular column portion 321a. A scraping blade 321b having a width that spans the front and back of the saw body 1 is formed at the tip of the inclined rectangular column portion 321a. In addition, a cutting blade 321c is formed on the side column side that is located closest to the base end of the saw body 1 among the side column sides that make up the inclined rectangular column portion 321a. The arranged inclined triangular prism teeth 321 are all formed to have the same rise angle A less than 90 degrees from the longitudinal side edge surface 1c of the saw body 1. This makes it possible to configure the size of the gaps S formed between the inclined triangular prism teeth 321 to be constant in the tooth rise direction.

[0026] Referring to FIG. 7, the inclined trapezoidal columnar teeth 322 rise flush with the front and back side surfaces 1a and 1b of the saw body 1 while alternately changing their orientation. With sides The saw blade 322 is provided with an inclined rectangular column portion 322a. A scraping blade 322b having a width that spans the front and back of the saw body 1 is formed at the tip of the inclined rectangular column portion 322a. In addition, a cutting blade 322c is formed on the side column side that is located closest to the base end of the saw body 1 among the side column sides that make up the inclined rectangular column portion 322a. The arranged inclined trapezoidal columnar teeth 322 are all formed with the same rise angle A less than 90 degrees from the longitudinal side edge surface 1c of the saw body 1. This makes it possible to configure the size of the gap S formed between each of the inclined trapezoidal columnar teeth 322 to be constant in the tooth rise direction.

[0027] 8, the vertical parallelogram columnar teeth 313 are used in a state where they are inserted here and there into the tooth rows of the vertical triangular columnar teeth 311 and the vertical trapezoidal columnar teeth 312. In Fig. 8, they are inserted into the tooth row of the vertical trapezoidal columnar teeth 312. The vertical parallelogram columnar teeth 313 have the function of sweeping out chips, so they are configured to be inserted, for example, every 5 to 15 vertical trapezoidal columnar teeth 312, with the front and back facing in an alternating manner. The vertical parallelogram-shaped teeth 313 rise flush with the front and back sides 1a and 1b of the saw body 1. With sidesA vertical prism portion 313a is provided. A scraping blade 313b having a width extending across the front and back of the saw body 1 is formed at the tip of the vertical prism portion 313a. A cutting blade 313c is formed on the side pillar side that is located closest to the base end of the saw body 1 among the side pillar sides that make up the vertical prism portion 313a. All of the rise angles A from the longitudinal side edge surface 1c of the saw body 1 are formed at the same angle of 90 degrees, and the dimension of the gap S between each of the vertical parallelogram columnar teeth 313 is constant in the tooth rise direction.

[0028] 9, the inclined parallelogram prismatic teeth 323 are used in a state where they are inserted here and there into the tooth rows of the inclined triangular prismatic teeth 321 and the inclined trapezoidal prismatic teeth 322. In Fig. 9, they are inserted into the tooth row of the inclined trapezoidal prismatic teeth 322. As with the vertical parallelogram prismatic teeth 313, the inclined parallelogram prismatic teeth 323 also have the function of sweeping out chips, so that they are inserted, for example, every 5 to 15 inclined trapezoidal prismatic teeth 322 with the front and back facing in an alternating manner. The inclined parallelogram-shaped teeth 323 rise flush with the front and back sides 1a and 1b of the saw body 1. With sides An inclined rectangular column portion 323a is provided. A cutting blade 323b having a width extending across the front and back of the saw body 1 is formed at the tip of the inclined rectangular column portion 323a. A cutting blade 323c is formed on the side column side that is located closest to the base end of the saw body 1 among the side column sides that make up the inclined rectangular column portion 323a. The rise angles A from the longitudinal side edge surface 1c of the saw body 1 are all formed to be the same angle less than 90 degrees, and the dimension of the gap S between each inclined parallelogram columnar tooth 323 is constant in the tooth rise direction.

[0029] 1 to 3, the second embodiment of the present invention is configured such that each prismatic tooth 3 arranged in the blade region Z of the saw body 1 is formed as an inclined prismatic tooth 32, all of which have the same rise angle A from the saw body 1. In addition, the incident angle B of the cutting blade 32c relative to the cutting edge line L is set in advance to an angle less than 90 degrees, and the set angle value is set as the inclination angle of the inclined columnar teeth 32, i.e., the rise angle A, to form an array of the inclined columnar teeth 32.

[0030] By inclining all of the inclined columnar teeth 32 arranged in the blade length region Z of the saw body 1 at the same angle, production and manufacturing are extremely simplified, and a saw without shape or size defects can be provided at low cost. In particular, if there is a preferred angle value as the incidence angle value B of the cutting blade 32c with respect to the cutting edge line L, the inclination angle (rise angle A) of the inclined columnar teeth 32 to be formed is the preferred angle value B of the cutting blade 32c with respect to the cutting edge line L. 32c The incidence angle B of the inclined columnar teeth 32 can be set as the rising angle A of the inclined columnar teeth 32. Therefore, the rising angle A of the inclined columnar teeth 32 can be directly used as the preferable incidence angle B of the cutting blade 32c to configure the saw. Moreover, by setting the rise angle A of the inclined columnar teeth 32 to a value less than 90 degrees, the incidence angle B of the cutting blade 32c can also be automatically set to the same value less than 90 degrees. This makes it possible for the saw's cutting action, which starts from the base end Z1 of the blade length region Z, to start from an incidence angle B of less than 90 degrees, which causes less biting.

[0031] As the inclined rectangular prismatic teeth 32, inclined triangular prismatic teeth 321, inclined trapezoidal prismatic teeth 322, and inclined parallelogram prismatic teeth 323 can be used.

[0032] 1 to 3, in a third embodiment of the present invention, a rise angle A of the inclined columnar teeth 32 is set to be equal to or greater than 70 degrees and less than 90 degrees. In addition, the blade region Z is curved from the base end Z1 to the tip end Z2 to increase the curvature of the inclined columnar teeth 32 by an angle C of 20 degrees or more and 40 degrees or less. Furthermore, the sum angle D of the rising angle A and the curve increase angle C is set to an angle of 120 degrees or less at the tip portion Z2 of the blade length region Z.

[0033] By setting the rise angle A at an angle of 70 degrees or more and less than 90 degrees, the incidence angle B of the cutting blade 32c with respect to the cutting edge line L is also the same at least 70 degrees and less than 90 degrees. Therefore, the actual cutting angle into the workpiece G at the base end Z1 of the blade region Z of the saw body 1 at which the cutting operation starts can also be set to the angle of 70 degrees or more and less than 90 degrees. By starting the cutting operation at a cutting angle of less than 90 degrees, biting into the workpiece G at the beginning of the cutting operation can be prevented, and a smooth sawing operation can be achieved. If the rise angle A is less than 70 degrees, the cutting angle into the workpiece G at the base end Z1 of the blade region where the cutting operation is likely to start also tends to be a low angle less than 70 degrees. Therefore, although the biting of the workpiece G by the cutting blade 32c at the base end Z1 of the blade region is suppressed, the cutting by the cutting blade 32c near the base end Z1 of the blade region tends to be insufficient. On the other hand, if the rise angle A is 90 degrees or more, the cutting angle of the cutting blade 32c at the base end Z1 of the blade region into the workpiece G at the beginning of the sawing operation tends to be too high, making jamming more likely to occur.

[0034] By setting the curvature increase angle C to an angle of 20 degrees or more and 40 degrees or less, the cutting action of the cutting blade 32c, which starts at the base end Z1 of the blade region, can be effectively increased toward the tip end Z2 of the blade region. Also, biting due to an excessive increase in the cutting angle of the cutting blade 32c can be effectively prevented. When the blade region Z is curved, the actual inclination of the cutting edge 32c of each of the arranged inclined rectangular columnar teeth 32 increases from the base end Z1 to the tip end Z2 of the blade region Z due to the curve. The increased angle due to this curve is called the curve increase angle C. When the curvature increase angle C is large, the cutting angle of the cutting blade 32c at the tip Z2 of the blade region into the workpiece G increases accordingly. When the cutting angle increases, the cutting effect improves, but the cutting blade 32c is more likely to bite into the workpiece G. If the curvature increase angle C is less than 20 degrees, a good increase in the cutting action from the base end Z1 to the tip end Z2 of the blade region Z cannot be expected compared to a rise angle of 70 degrees or more and less than 90 degrees at the base end Z1 of the blade region Z. On the other hand, if the curvature increase angle C exceeds 40 degrees, the cutting edge 32c is more likely to bite at the tip end Z2 of the blade region.

[0035] By configuring the additional angle D to be an angle of 120 degrees or less at the tip Z2 of the blade region, the actual cutting angle of the cutting blade 32c near the tip Z2 of the blade region can be prevented from becoming too large, thereby ensuring good cutting operation. The additional angle D is the sum of the rising angle A of the inclined rectangular columnar tooth 32 (the incidence angle B of the cutting blade 32c) and the curved increase angle C The angle obtained by adding It is. The added angle D can be said to be the actual inclination angle of the cutting edge 32c at the tip Z2 of the blade region, taking into account the increase in angle (C) of the inclined columnar teeth 32 due to the curvature of the blade region Z. If the additional angle D exceeds 120 degrees, the cutting edge 32c is likely to get caught at the tip portion Z2 of the blade region.

[0036] 1 to 3, in a fourth embodiment of the present invention, two of three angle conditions consisting of the value of the rise angle A, the value of the curvature increase angle C, and the value of the addition angle D are preset, and one of two dimensional conditions consisting of the value of the blade length W of the saw body 1 and the value of the curvature radius R of the cutting edge line L is preset, and the remaining one angle condition and one dimensional condition are calculated and set from the two preset angle conditions and one dimensional condition.

[0037] For example, in Example 1, the rise angle A and the curvature increase angle C are preset as two desired angle conditions out of three angle conditions, and the blade length W is preset as one desired dimensional condition out of two dimensional conditions. In this case, the remaining angle condition, the added angle D, is calculated as D=A+C. The remaining dimensional condition, the radius of curvature R, is calculated as R=360W / 2πC, where π is the constant of the circumference of a circle. As an example 2, the rise angle A and the curve increase angle C are preset as two desired angle conditions out of three angle conditions, and the curvature radius R is preset as one desired dimension condition out of two dimension conditions. The remaining angle condition, the added angle D, is calculated as D=A+C. The remaining dimensional condition, the blade length W, is calculated as W=2πR·C / 360. In Example 3, the rise angle A and the addition angle D are preset as two desired angle conditions out of three angle conditions, and the curvature radius R is preset as one desired dimension condition out of two dimension conditions. The remaining angle condition, the curvature increase angle C, is calculated as C=DA. The remaining dimensional condition, the blade length W, is calculated as W=2πR·C / 360.

[0038] As described above, in the fourth embodiment of the present invention, two desired angle conditions are preset from the three angle conditions consisting of the value of the rise angle A, the value of the curvature increase angle C, and the value of the addition angle D, and two desired conditions are preset from the two dimensional conditions consisting of the value of the blade length W of the saw body 1 and the value of the curvature radius R of the cutting edge line L, thereby making it possible to provide curved saws with a variety of desired angle conditions and desired dimensional conditions, with good cutting action and good anti-jamming action.

[0039] 1 to 3, in the fifth embodiment of the present invention, as described in Example 1 of the fourth embodiment above, the value of the rise angle A of the inclined columnar tooth 32, the value of the curvature increase angle C, and the blade length W of the saw body 1 are preset, and the value of the addition angle D and the value of the radius of curvature R of the cutting edge line L are calculated and set from the value of the rise angle A, the value of the curvature increase angle C, and the blade length W that have been preset. Therefore, by determining in advance the desired rise angle A, desired curvature increase angle C, and desired blade length W, the value of the other added angle D and the value of the radius of curvature R of the cutting edge line L can be calculated. With the values ​​of these five conditions, a curved saw with the desired rise angle A, desired blade length W, and desired curvature increase angle C can be easily provided with good cutting action and good anti-jamming action.

[0040] 1 to 3, in the sixth embodiment of the present invention, as described in Example 3 of the fourth embodiment above, the value of the rise angle A of the inclined columnar tooth 32, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L are preset and determined, and the value of the remaining curvature increase angle C and the blade length W are calculated and set. Therefore, by determining in advance the values ​​of the rise angle A, the addition angle D, and the radius of curvature R of the cutting edge line L, the value of the increased curvature angle C and the blade length W can be calculated. With the values ​​of these five conditions, a curved saw with the desired rise angle A, desired addition angle D, and desired radius of curvature R can be easily provided with good cutting action and good anti-jamming action.

[0041] 1 to 3, in a seventh embodiment of the present invention, the value of the rise angle A of the inclined columnar tooth 32, the value of the addition angle D, and the value of the blade length W of the saw body 1 are preset and determined, and the value of the curvature increase angle C and the value of the radius of curvature R of the cutting edge line L are calculated and set from the value of the rise angle A, the value of the addition angle D, and the value of the blade length W. In this case, the remaining angle condition, the curvature increase angle C, is calculated as C=DA. The remaining dimensional condition, the radius of curvature R, is calculated as R=360W / 2πC. Therefore, by determining in advance the values ​​of the rise angle A, the additional angle D, and the blade length W, it is possible to calculate the value of the curvature increase angle C and the value of the curvature radius R of the cutting edge line L. Then, with the obtained values ​​of these five conditions, it is possible to easily provide a curved saw with the desired rise angle A, desired additional angle D, and desired blade length W, which has good cutting action and good jamming prevention action.

[0042] 1 to 3, in an eighth embodiment of the present invention, the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W of the saw blade 1 are set in advance, and the value of the rise angle A and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the curvature increase angle C, the value of the addition angle D, and the value of the blade length W. In this case, the remaining angle condition, the rising angle A, is calculated as A=DC. The remaining dimensional condition, the radius of curvature R, is calculated as R = 360W / 2πC. Therefore, by determining in advance the values ​​of the curvature increase angle C, the addition angle D, and the blade length W, it is possible to calculate the value of the rise angle A and the value of the curvature radius R of the cutting edge line L. Then, with the obtained values ​​of these five conditions, it is possible to easily provide a curved saw with the desired curvature increase angle C, the desired addition angle D, and the desired blade length W, with good cutting action and good jamming prevention action.

[0043] 1 to 3, in a ninth embodiment of the present invention, the value of the curvature increase angle C, the value of the addition angle D, and the value of the radius of curvature R of the cutting edge line L are set in advance, and the values ​​of the rise angle A and the blade length W are calculated and set from the value of the curvature increase angle C, the value of the addition angle D, and the value of the radius of curvature R of the cutting edge line L. In this case, the remaining angle condition, the rising angle A, is calculated as A=DC. The remaining dimensional condition, the blade length W, is calculated as W = 2πR·C / 360. Therefore, by determining in advance the values ​​of the curvature increase angle C, the addition angle D, and the radius of curvature R of the cutting edge line L, it is possible to calculate the value of the rise angle A and the blade length W. Then, with the obtained values ​​of these five conditions, it is possible to easily provide a curved saw with the desired specified curvature increase angle C, the desired specified addition angle D, and the desired specified radius of curvature R, which has good cutting action and good anti-jamming action. [Industrial Applicability]

[0044] The curved saw of the present invention has industrial applicability as a hand saw. [Explanation of symbols]

[0045] 1 saw blade 1a Front side 1b Back side 1c Longitudinal side edge surface 2 Grip body 3 Prismatic teeth 3a Square column 3b Shaving blade 3c Cutting blade 31 Vertical prismatic teeth 31a Vertical prism section 31b Shaving blade 31c Cutting blade 32 Oblique prismatic teeth 32a Inclined rectangular column 32b Shaving blade 32c cutting blade 311 Vertical triangular prism tooth 311a Vertical prism section 311b Sharpening blade 311c Cutting blade 312 Vertical trapezoidal tooth 312a Vertical prism section 312b Sharpening blade 312c cutting blade 313 Vertical parallelogram-shaped tooth 313a Vertical prism section 313b Sharpening blade 313c Cutting blade 321 Inclined triangular prism teeth 321a Inclined rectangular column 321b Sharpening blade 321c cutting blade 322 Inclined trapezoidal columnar teeth 322a Inclined rectangular column 322b Sharpening blade 322c cutting blade 323 Inclined parallelogram-shaped tooth 323a Inclined rectangular column 323b Sharpening blade 323c cutting blade A Rise Angle B Incident angle C Curvature Increase Angle D Addition angle G Object to be cut K center of curvature L cutting edge line L1: Cutting edge line at the base end Z1 of the cutting edge area L2: Cutting edge line at the tip of the cutting edge area Z2 W Blade length R radius of curvature S Gap Z Blade length area Z1 Base end of blade area Z2 Tip of the cutting edge area

Claims

1. A curved saw in which saw teeth are arranged in the longitudinal direction of a saw body 1 and a cutting edge line L formed by the arranged saw teeth is curved from a base end side to a tip end side of the saw body 1, The saw teeth arranged on the curved saw are prismatic teeth 3 consisting of triangular prism teeth or quadrangular prism teeth, Each of the prismatic teeth 3 has a prismatic portion 3a with side surfaces rising flush from the front and back sides of the saw body 1 while changing the direction alternately, a scraping blade 3b having a width that spans the front and back sides of the saw body 1 is formed at the tip of the prismatic portion 3a, and a cutting blade 3c is formed at the side pillar side that is located closest to the base end side among the side pillar sides that constitute the prismatic portion 3a, Furthermore, the arranged prismatic teeth 3 are all formed with the same rise angle A from the longitudinal side edge surface 1c of the cutting edge region Z of the saw body 1, so that the size of the gap S formed between each of the prismatic teeth 3 is constant in the tooth rise direction. The curved saw is further characterized in that each of the prismatic teeth 3 arranged on the saw body 1 is formed as an inclined prismatic tooth 32 in which the rise angle A from the saw body 1 is inclined at the same angle, and the rise angle A of each of the inclined prismatic teeth 32 is configured to match an angle of less than 90 degrees that is preset as the incident angle B of the cutting blade 32C relative to the cutting edge line L.

2. The curved saw as described in claim 1, characterized in that the rise angle A of the inclined columnar teeth 32 is an angle of 70 degrees or more and less than 90 degrees, the increased curvature angle C of the inclined columnar teeth 32 which increases as the blade length region Z is curved from the base end Z1 to the tip end Z2 is an angle of 20 degrees or more and 40 degrees or less, and the added angle D of the rise angle A and the increased curvature angle C is an angle of 120 degrees or less at the tip end Z2 of the blade length region Z.

3. The curve saw described in claim 2, characterized in that two of the three angle conditions consisting of the value of the rise angle A, the value of the curvature increase angle C, and the value of the additional angle D are set in advance, and one of the two dimensional conditions consisting of the value of the blade length W of the saw body 1 and the value of the curvature radius R of the cutting edge line L is set in advance, and the remaining one angle condition and one dimensional condition are calculated and set from the two angle conditions and one dimensional condition set in advance.

4. The curve saw according to claim 3, characterized in that the value of the rise angle A of the inclined rectangular columnar teeth 32, the value of the curvature increase angle C, and the blade length W of the saw body 1 are preset, and the value of the added angle D and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the rise angle A, the value of the curvature increase angle C, and the value of the blade length W.

5. The curved saw according to claim 3, characterized in that the value of the rise angle A of the inclined rectangular columnar teeth 32, the value of the addition angle D, and the value of the radius of curvature R of the cutting edge line L are set in advance, and the value of the curvature increase angle C and the blade length W of the saw body 1 are calculated and set from the value of the rise angle A, the value of the addition angle D, and the value of the radius of curvature R of the cutting edge line L.

6. 4. The curve saw according to claim 3, wherein the value of the rise angle A of the inclined columnar teeth 32, the value of the addition angle D, and the value of the blade length W of the saw body 1 are preset, and the value of the curvature increase angle C and the value of the curvature radius R of the cutting edge line L are calculated and set from the value of the rise angle A, the value of the addition angle D, and the value of the blade length W.

7. A curved saw as described in claim 3, characterized in that the value of the increased curvature angle C, the value of the added angle D, and the value of the blade length W of the saw body 1 are set in advance, and the value of the rise angle A and the value of the radius of curvature R of the cutting edge line L are calculated and set from the value of the increased curvature angle C, the value of the added angle D, and the value of the blade length W.

8. The curve saw according to claim 3, characterized in that the value of the curvature increase angle C, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L are set in advance, and the values ​​of the rise angle A and the blade length W are calculated and set from the value of the curvature increase angle C, the value of the addition angle D, and the value of the curvature radius R of the cutting edge line L.

9. A curved saw as described in any of claims 1 to 8, characterized in that the arrangement of the inclined rectangular prismatic teeth 32 is configured as either an arrangement of inclined triangular prismatic teeth 321, or an arrangement of inclined trapezoidal prismatic teeth 322, or an arrangement in which inclined parallelogram prismatic teeth 323 are mixed in between an arrangement of inclined triangular prismatic teeth 321, or an arrangement in which inclined parallelogram prismatic teeth 323 are mixed in between an arrangement of inclined trapezoidal prismatic teeth 322.

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