JP2009078486A - Engraving stylus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engraving stylus for an image engraving apparatus which performs engraving on paper or a plastic sheet in a scanning form by a relative movement between the engraving stylus and a plate to be engraved, incapable of scraping off the surface to a precise depth without breaking the plate to be engraved. <P>SOLUTION: The engraving stylus is equipped with a cutting edge, at the front edge of the engraving stylus, which has an opening angle of an obtuse angle not less than 120 degrees, a rake angle of an acute angle not more than 5 degrees, and a front clearance angle in the range of 20 to 45 degrees. A difference between the left opening angle and the right opening angle is set within one degree. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  With respect to the engraving needle used in the engraving apparatus that performs engraving in a scanning manner by the relative movement of the engraving needle and the plate to be engraved, accurate engraving can be performed in the depth direction and the width direction when engraving on the plate to be engraved. It relates to engraving needles.

  There is an image engraving apparatus that performs engraving on a thin plate made of paper or plastic by a relative movement of an engraving needle and a plate to be engraved (see Patent Document 1). In this image engraving apparatus, the engraving plate mounted on the base reciprocates in the horizontal direction, and the engraving needle lowered from the vertical direction scrapes off the engraving plate made of paper or plastic from the surface. Do the openwork. The above-mentioned engraved board thus engraved is used as a personal authentication card or a security sheet for important documents (see Patent Documents 2 and 3).

  Conventionally, there has been a diamond stylus used for engraving a gravure cylinder used for printing (see Patent Document 4). This is an engraving needle for making a recess for accumulating ink on a cylinder for performing gravure printing, and using these, a paper or plastic made of paper or plastic is scanned by the relative movement of the engraving needle and the plate to be engraved. Even when used in an image engraving apparatus for engraving a thin plate, the engraved plate could only be recessed, and the surface could not be scraped to an accurate depth.

Japanese Patent Laid-Open No. 05-024394 JP 2007-118395 A JP 2007-130855 A JP 11-291437 A

  The problem to be solved is that an image engraving apparatus that engraves a thin sheet of paper or plastic by scanning with the relative movement of the engraving needle and the plate to be engraved cannot scrape the surface with an accurate depth and width. It is a point.

  The most important feature of the engraving needle of the present invention is that the front surface, which stands substantially perpendicular to the cutting direction, is flat, has a pair of cutting edges at the tip, and has a clearance surface with a predetermined clearance angle on the rear side. Features.

  The most important feature of the engraving needle of the present invention is that the front surface, which stands substantially perpendicular to the cutting direction, is flat, has a pair of cutting edges at the tip, and has a clearance surface with a predetermined clearance angle on the rear side. Due to the features, it has become possible to scrape the surface with an accurate depth and width. At that time, even if the plate to be engraved is a thin plate made of paper or plastic, engraving is possible without breaking them.

  In the engraving needle used in the engraving device that performs engraving in a scanning manner by the relative movement of the engraving needle and the plate to be engraved, there is a problem that the engraving cannot be performed at the correct depth and width, The problem that engraving is not possible without breaking the thin plate is that the opening angle of the cutting edge at the tip of the engraving needle is an obtuse angle of 120 degrees or more, the forward tilt angle is an acute angle of 5 degrees or less, and the front relief angle is 20 degrees to 45 degrees. It was solved by setting the range of degrees.

  FIG. 1 is a three-side view of an engraving needle 10 (including both a tip portion 31 and a support rod portion 11) according to an embodiment of the present invention.

  FIG. 1A is a front view of the engraving needle viewed from the direction of travel of the engraving scanning direction.

  FIG. 1B is a bottom view of the engraving needle viewed from the engraved plate side.

  FIG. 1C is a side view of the engraving needle viewed from the side surface in the scanning direction.

  FIG. 2 is an enlarged view showing the structure of a diamond tip 31 (engraving needle) attached to the tip of the tip.

  FIG. 2A shows an enlarged side view, and FIG. 2B shows an enlarged rear view.

  The engraving needle 10 (including both the tip portion 31 and the support rod portion 11) includes a metal support rod 11 and a diamond tip 31 (engraving needle) attached to the tip of the metal support rod 11. Diamond is the hardest material for engraving needles and has the best performance. It is also possible to use carbide steel as a material other than diamond.

  The metal support bar 11 has a rotation-preventing portion 13 having a cylindrical one side surface made flat. The support rod 11 has a recess 15 at the tip, and a diamond chip 31 having a cross section formed on a flat plate is abutted and supported on a surface 18 processed into a plane along the axial direction of the cylinder. As a support method, in the embodiment, a method of fixing using an adhesive is used, but a method of performing in combination with a shape processing or a method of using a stopper may be used.

  The back surface of the recess 15 of the support bar 11 has a relief surface 17 that is continuous with the relief surfaces 37L and 37R of the diamond tip 31, and has a structure in which chips do not stagnate behind the cutting edges 35L and 35R. .

  As an example of the size of the support rod 11 and the diamond chip 31, the dimensions of each part are shown in FIGS. The support rod 11 has a diameter of 2 mm and a total length of 10 mm with the diamond tip 31 supported. The diamond chip 31 has a width of 1 mm, a height of 1.95 mm, and a thickness of 0.6 mm. Both the support bar 11 and the diamond chip 31 are not limited to the dimensions of the embodiment described here, and may be larger or smaller.

  FIG. 2 shows an enlarged view of the state in which the diamond chip 31 is in contact with the plate 51 to be engraved. Cutting proceeds in the direction of the arrow shown in FIG. For cutting, a method of moving the engraving needle 10 or a method of moving the plate 51 to be engraved may be used.

  The diamond chip 31 has a front surface 33 (FIG. 2 (A)) that stands substantially perpendicular to the plate to be engraved, and the rake angle α (FIG. 1 (C)) is 5 degrees or less. Cutting is performed accurately. A typical rake angle is 3 degrees and 50 minutes.

  As shown in FIG. 1 (A), the tip of the engraving needle has an opening angle between the left cutting blade 35L and the right cutting blade 35R, that is, an obtuse angle where the sum of δR and δL is 120 degrees or more. Cutting can be performed most accurately when δR is 65 degrees and δL is 64 degrees and 40 minutes, and there is a difference in opening angle within one time.

  The reason why cutting can be performed more accurately when the left and right sides are asymmetric is considered to be as follows. The diamond chip 31 descends from the upper part in the vertical direction, contacts the plate 51 to be engraved, and the engraving needle 10 advances in the direction indicated by the arrow in FIG. However, since there is a difference between the left and right opening angles from the vertical direction, there is a difference between the left and right cutting blades 35L and 35R around the plate 51 to be engraved. If there is no difference and the left and right opening angles are exactly the same, a strong force is applied from both the left and right blades after contacting the tip, and the blade gets caught on the engraved surface and breaks the paper or plastic sheet. However, the problem was solved by providing a difference in the left and right opening angles as in the example.

  Further, with respect to the clearance angle β (FIG. 1C), in order to maintain the strength of the tip, when the angle is 20 degrees to 45 degrees as shown in FIG. 1C, typically 25 degrees. Cutting is possible without chips remaining at the tip. Further, a sufficient cutting edge angle of 61 degrees and 10 minutes was obtained from the rake angle of 3 degrees and 50 minutes and the clearance angle of 25 degrees, and the life of the tip of the diamond tip 31 was extended.

  In the present embodiment, as shown in FIG. 2B, the shape of the tip portion of the diamond tip 31 is formed by sharpening the original processing surfaces 39L and 39R processed by an angle slightly larger than the clearance angle β and the cutting edges 35L and 35R. In order to achieve this, it comprises polishing surfaces 37L and 37R created by polishing the cutting edge side of the original processing surface. Regardless of the method, a method may be used in which all the polished surfaces are provided without leaving the original processed surfaces 39L and 39R. In either case, the polishing surfaces 37L and 37R serve as flank surfaces of the diamond tip 31.

[Effect of Example]
The engraving needle of the embodiment of the present invention has made it possible to:

  With the engraving needle used in the engraving machine that performs engraving in a scanning manner by the relative movement of the engraving needle and the plate to be engraved, it has become possible to cut the engraved plate with an accurate depth and width, especially a thin plate of paper or plastic. .

[Others]
The term engraving needle was used to mean both the case where only the diamond tip 31 portion at the tip of the embodiment is shown and the engraving needle 10 as a whole including both the diamond tip 31 and the support rod 11.

It is a three-view figure of the sculpture needle of the example of the present invention (example 1). (Example 1) which is an enlarged view of the front-end | tip part of the engraving needle of an Example of this invention.

Explanation of symbols

10 Engraving needle (both tip 31 and support bar 11)
11 Support Rod 15 Recess 17 Support Flank 31 Diamond Tip (Engraving Needle)
33 Front 35L, 35R Cutting edge 37L, 37R Polished surface (flank)
39L, 39R Original machining surface α Rake angle β Relief angle δL Cutting blade left opening angle δR Cutting blade right opening angle

Claims (11)

An engraving needle characterized by having a flat front surface erected substantially perpendicular to the cutting direction, having a pair of cutting edges at the tip, and a flank with a predetermined clearance angle on the rear side. The engraving needle of claim 1,
The engraving needle is supported by a tip portion of a support bar that stands up substantially perpendicular to the cutting direction. The engraving needle according to claim 1 or 2,
The support rod has a recess at a tip, and the engraving needle is supported in the recess. The engraving needle according to any one of claims 1 to 3,
The support rod has a detent portion having a part made flat along the axial direction of the cylinder. The engraving needle according to any one of claims 1 to 4,
The support rod has a flank that is continuous with the flank of the engraving needle. The engraving needle according to any one of claims 1 to 5,
The engraving needle characterized in that the opening angle of the cutting blade of the engraving needle is an obtuse angle of 120 degrees or more. The engraving needle according to any one of claims 1 to 6,
The engraving needle characterized in that the rake angle of the engraving needle is an acute angle of 5 degrees or less. The engraving needle according to any one of claims 1 to 7,
The relief angle of the engraving needle is in the range of 20 degrees to 45 degrees. The engraving needle according to any one of claims 1 to 8,
The engraving needle characterized in that the opening angle of the cutting blade of the engraving needle is asymmetric. The engraving needle of claim 9,
The difference between the left and right opening angles of the engraving needle is within 1 degree. The engraving needle according to any one of claims 1 to 10,
The engraving needle is made of diamond or cemented carbide.

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