JP2005288633A - Cutting tool and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting tool in which such part of the cutting edge as always abutting to the side face of a cutting groove of a work is minimized so as to make the load constant with less load variation even if a shake in hand is generated, capable of making unlikely to generate a scratch at the surface of a disc-shaped base board. <P>SOLUTION: The cutting tool 10 is equipped with a cutting edge part 2 on the peripheral surface of the disc-shaped base board 1 in such an arrangement as given a greater thickness than the base board 1, in which a base board protecting material 5 is laid on the obverse and reverse surfaces of the base board 1, wherein the upper surface of the protecting material 5 is set lower than the cutting edge part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cutting tool used for cutting a workpiece such as concrete, stone, or block.

  In general, a cutting tool (also referred to as a grinding tool) has a disk shape and is used when a workpiece such as a stone is cut. Fig.8 (a) is a top view of the cutting tool which is a conventional diamond cutter, (b) is sectional drawing of (a). As shown in FIG. 8A, the conventional cutting tool 20 is provided with a cutting edge portion 22 on the outer peripheral surface of a disk-shaped substrate 21. The cutting edge portion 22 is mixed with diamond particles of a grinding wheel and has sufficient strength against a workpiece to be cut. A plurality of slit grooves 23 are formed in the cutting edge portion 22 (see, for example, Patent Document 1). Furthermore, as shown in FIG. 8B, a mounting hole 21 c is formed in the center of the cutting tool 20.

  The spindle 31 of the disc grinder 30 referred to in FIG. 1C is inserted into the mounting hole 21c of the cutting tool 20, and the disc grinder 30 is formed by a flange 32, a bush 33, a tightening nut 34, and the like as tightening members. The spindle 31 is used by being fixed. When the disc grinder 30 equipped with the conventional cutting tool 20 is activated, the cutting tool 20 rotates, for example, the cutting groove 36 is processed in the concrete 35, and the cutting process is performed.

  However, the cutting tool 20 having such a configuration has the following problems. That is, in the cutting tool 20, when the cutting groove 36 is gradually processed deeper, the surface of the substrate 21 is shaken due to camera shake, and the front surface 21a and the back surface 21b (see FIG. 8B) of the substrate 21 are generated. It contacts the upper surface 36a or the lower surface 36b (see FIG. 1C) of the cutting groove 36. Then, the opposite surface is also contacted by the reaction, and there is a problem that the front surface 21a and the back surface 21b of the substrate 21 can be scratched. As shown in FIGS. 8A and 8B, a so-called neck wear occurs due to such uneven scratches. For this reason, there was a problem that the cutting tool 20 could not be used due to wear under the neck of the substrate 21 even though the cutting edge portion 22 could still be used sufficiently. Further, in the cutter having the slit groove 23, when a scratch is formed in the slit portion, stress concentration occurs in the scratch, which causes the substrate to crack and shortens the life of the cutting tool 20.

Therefore, a blade having a long life and good sharpness that does not cause wear under the neck of the substrate has been conventionally proposed (for example, see Patent Document 2). Fig.9 (a) is a front view of a cutting tool, (b) is sectional drawing of the AA line shown to (a). As shown in FIG. 9A, a superabrasive layer 42 obtained by mixing diamond and CBN abrasive grains with metal powder and sintering is disposed on the outer periphery of the steel substrate 41. The legged tip 42A of the superabrasive layer 42 is a tip (legged tip) having the superabrasive layer 42 extended to the inner peripheral side of the substrate 41 in order to prevent under-neck wear. As shown in FIG. 9B, the thickness b of the legged tip 42 </ b> A is characterized by being extended to be equal to the thickness a of the superabrasive layer 42.
Japanese Patent Laid-Open No. 2003-159656 (FIGS. 1, 4, 5, and 6) JP-A-8-90425 (paragraph numbers 0011 to 0016, FIGS. 3, 4, and 5)

  However, by extending the thickness a of the superabrasive layer 42 to be equal to the thickness b of the legged tip 42A, even if it is possible to prevent under-neck wear of the substrate, the tip (cutting blade) is used in the workpiece cutting process. Since it always hits the side of the cutting groove, there was a problem that the cutting resistance increased. Further, when the cutting resistance is increased, there is a problem that the cutting force is reduced and the sharpness is deteriorated.

  Therefore, the present invention was devised to solve these problems, and the cutting edge that always hits the side of the cutting groove of the workpiece is minimized so that the load is constant and the load fluctuates even if camera shake occurs. It is an object of the present invention to provide a cutting tool that hardly causes scratches on the surface of a disk-shaped substrate.

  The invention of claim 1 devised to solve such a problem is a cutting tool in which a cutting edge portion is provided on the outer peripheral surface of a disk-shaped substrate so as to be thicker than the substrate. A protective material is provided, and the upper surface of the substrate protective material is set lower than the cutting edge portion.

  In this way, the substrate protection material is disposed in the step between the cutting edge portion on the front and back surfaces of the substrate and the substrate, and the upper surface of the substrate protection material is formed lower than the cutting edge portion, so that the substrate protection Constant contact of the material with the workpiece can be avoided. Further, when the workpiece and the substrate are in contact, such as when the substrate is bent due to stress, or when the cutter enters obliquely, the substrate protective material strikes the workpiece before the substrate surface.

  Invention of Claim 2 is the cutting tool which concerns on Claim 1, Comprising: The said board | substrate protection material is comprised from the base material fixed to the said board | substrate, and the abrasive grain provided in the upper surface of this base material It is characterized by that. Thus, by comprising a substrate protective material from a base material and an abrasive grain, the substrate protective material by various combinations of a base material and an abrasive grain can be formed easily.

The invention of claim 3 is a method for manufacturing a cutting tool, the first step of forming the substrate protective material into a desired size and shape, temporarily fixing the substrate protective material on the front and back surfaces of the substrate, A second step of temporarily fastening a cutting blade portion thicker than the thickness of the substrate and the substrate protection material on the outer peripheral surface; and loading the substrate protection material and the cutting blade portion onto the substrate temporarily attached to the mold And a third step of pressing and a fourth step of sintering the mold.
Thus, the manufacturing method of the cutting tool which can arrange | position a board | substrate protective material firmly to a cutting tool by stepping on the 1st process to the 4th process can be provided.

Invention of Claim 4 is a manufacturing method of a cutting tool, Comprising: The 1st process which forms the hollow of a desired size shape in a board | substrate, and the board | substrate protective material produced | generated by adding an abrasive grain to a metal bond to the said hollow A second step of filling and temporarily fastening a cutting blade portion thicker than the thickness of the substrate and the substrate protective material on the outer peripheral surface of the substrate; and the substrate protective material and the cutting blade portion are temporarily attached. The method includes a third step in which a cutting edge portion provided on the substrate is loaded into a die and pressed, and a fourth step in which the die is sintered.
Thus, the manufacturing method of the cutting tool which can arrange | position a board | substrate protective material firmly to the hollow formed in the cutting tool by performing the step of a 1st process to a 4th process can be provided.

According to the invention according to claim 1, since the substrate protective material is disposed on the front and back surfaces of the substrate and the upper surface of the substrate protective material is set lower than the cutting edge portion, it is possible to prevent under-neck wear of the substrate, Moreover, since the cutting edge portion is not extended with the same thickness in the process of cutting the workpiece, the front and back surfaces of the substrate do not always hit the side of the cutting groove of the workpiece, and the cutting resistance is small. Moreover, since cutting resistance does not become large, sharpness can be maintained.
Furthermore, by arranging the substrate protection material on the front and back surfaces of the substrate of the cutting tool, when the workpiece cutting groove is deep, and the hand shake caused by the hand cruciform occurs, the substrate protection material comes into contact with the workpiece side, Since the substrate protective material protects the substrate and the substrate protective material made of fine abrasive grains reduces the friction by performing a small amount of polishing, a cutting tool with less load fluctuation can be provided. Further, since the surface of the substrate can provide a cutting tool that does not wear due to scratches, the life of the cutting tool can be extended.

  According to the invention according to claim 2, since the substrate protective material is composed of the base material and the abrasive grains, the substrate protective material can be easily formed by various combinations of the base material and the abrasive grains. Easy and inexpensive.

  According to the invention which concerns on Claim 3, the cutting tool which fixed the board | substrate protective material to the cutting tool firmly can be provided by stepping on the 1st process to the 4th process.

  According to the invention of claim 4, by taking the steps from the first step to the fourth step, the substrate protective material is securely fixed to the recess formed in the cutting tool, and easily corresponds to the thickness of the cutting edge portion. A cutting tool can be provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Fig.1 (a) is a top view of the diamond cutter which is a cutting tool, FIG.1 (b) is sectional drawing of (a). As shown in FIG. 1A, a cutting tool (hereinafter also referred to as a cutter) 10 includes a disk-shaped substrate 1 and a cutting edge portion 2 provided on the outer peripheral surface of the substrate 1.
The substrate 1 is a metal plate such as an iron plate. As an example, the diameter is φ94 and the plate thickness c is 1.4 mm.
The cutting edge portion 2 contains diamond particles as an abrasive, and is formed, for example, by biting the outer periphery of the substrate 1 by 1.5 mm, and the cutting edge portion 2 has a diameter of φ105. Moreover, the thickness a of the cutting edge part 2 is formed to 3.0 mm as an example, and a plurality of slit grooves 3 are formed at predetermined intervals.
Further, as shown in FIG. 1 (b), one or more (four in this case) substrate protective materials 5 formed in a circular shape having a desired shape are disposed on the front surface 1a and the back surface 1b of the substrate 1. ing. When the thickness of the substrate protective material 5 is, for example, 0.1 mm, the thickness b at the position where the substrate 1 and the substrate protective material 5 after the substrate protective material 5 is disposed is 1.6 mm.

  The substrate protective material 5 includes a base material 5 a fixed to the substrate 1 and abrasive grains 5 b disposed on the upper surface of the base material 1. The base material 5a is a metal thin plate, and here, a sheet-like material in which abrasive grains 5b are uniformly coated on one side of the metal thin plate by a metal bond is formed into a circular shape. Moreover, the metal thin plate of the base material 5a used for the substrate protective material 5 may be a copper thin plate, and the abrasive grains 5b may be attached to one surface thereof by plating.

As shown in FIG. 1A, the substrate protective material 5 covers a ring-shaped area having an outer diameter φa and an inner diameter φb on the substrate 1 when the substrate 1 rotates, for example, when the diameter is φd. It will be. In general, the rotational speed of the disc grinder 30 (see FIG. 1C) is commercially available with a specification of 9,000 to 12,000 min ⁻¹ . 9,000 to 12,000 revolutions per minute corresponds to 150 to 200 revolutions per second. For example, assuming that the time of the hand shake caused by the hand knuckles is 0.01 s, the number of the substrate protective materials 5 may be one because the rotation is 1.5 to 2 at the time of the hand shake. That is, at the moment of camera shake, the substrate protective material 5 acts to separate the contact between the surface of the substrate 1 and the workpiece.
Here, the number of the substrate protection members 5 is four, which is four equally distributed. If there are four, more stable camera shake countermeasures are possible. In addition to four, two, three, five, six, etc. may be used. The attachment position of the substrate protection material 5 is preferably in the vicinity of the cutting edge portion 2.

Next, a method for manufacturing the cutting tool 10 will be described. FIG. 2 is a flowchart for explaining the manufacturing method. As shown in FIG. 2, the first step is a step of forming the substrate protective material 5 into a desired size and shape. Since the substrate protective material 5 is in the form of a sheet, it can be easily formed with a blade.
The second step is a step of temporarily fixing the substrate protective material 5 to the front and back surfaces 1 a and 1 b of the substrate 1. Since the back surface of the substrate protective material 5 is a metal plate surface, it can be pasted with glue as a temporary fastening. Alternatively, spot welding may be used instead of gluing. However, when fixing by spot welding, it is desirable to consider conductivity as will be described later in FIG.
The third step is a step in which the substrate 1 temporarily fixed to the substrate protective material 5 is loaded into a mold and pressed. FIG. 3 is a cross-sectional view showing a state in which the substrate 1 is loaded on the lower die 7, the middle die 8, and the upper die 9 made of carbon. As shown in FIG. 3, a positioning pin 6 for positioning is inserted through the center of the mold. The mold is formed of sintered carbon, the substrate 1 temporarily fixed to the substrate protective material 5 is loaded on the lower mold 7, sealed in multiple stages with the middle mold 8, and finally sealed with the upper mold 9, Press from above.
The fourth step is a step of sintering the mold. At this time, the upper surface of the substrate protective material 5 is set to be lower than the upper surface of the cutting edge portion 2.
In this sintering, the sintering temperature is heated to 600 to 1000 ° C., and the cutting edge portion 2 is also sintered at the same time, but the cutting edge portion 2 is set to be thicker than the combined thickness of the substrate 1 and the substrate protective material 5. Has been.
By performing these first to fourth steps, it is possible to provide the cutting tool 10 to which the substrate protective material 5 is firmly fixed.

  FIG.1 (c) is explanatory drawing which shows the use condition. As shown in FIG. 1 (c), when a cutting tool 10 having a plurality of substrate protective materials 5 disposed on a disk grinder 30 is fixed and a cutting groove 36 is cut into the concrete 35, camera shake occurs, resulting in the surface of the substrate 1. Variation occurs. At this time, the front and back surfaces of the substrate 1 are in contact with the cut surfaces of the upper surface 36 a and the lower surface 36 b of the cutting groove 36 of the concrete 35. Since the upper and lower surfaces of the substrate protective material 5 protrude slightly convexly from the front and back surfaces of the substrate 1, the substrate protective material 5 first comes into contact. If it does so, the board | substrate protective material 5 arrange | positioned by the front and back of the board | substrate 1 will contact | abut so that it may slide by reducing a friction by performing a trace amount grinding | polishing. And since the hardness of the abrasive grains which are fine particles coated on the upper surface of the substrate protective material 5 is much higher than the concrete 35, the abrasive grains of the substrate protective material 5 will polish the workpiece as a result. Therefore, the substrate protection material 5 realizes a cutting tool 10 with a small load variation and a constant load. Further, the original surface without scratches can be maintained on the surface of the substrate.

  FIG. 4 is related to the other structure of the cutting tool of this invention, FIG. 4 (a) is a top view of a cutting tool, (b) is sectional drawing of (a). 1 is different from the cutting tool 10 of FIG. 1 in that the placement of the substrate protective material 15 is fixed by spot welding, so that the upper surface of the metal plate as the base material 15a of the substrate protective material 15 is exposed and spot welding is performed. The point is that the abrasive grains 15b provided via metal bonds are formed in an annular shape. As shown in FIG. 4, the substrate protective material 15 is formed by uniformly coating the surface of the metal thin plate, which is the base material 15 a, with abrasive grains 15 b in an annular shape through metal bonds. A location 15c (see FIG. 1 (a)) where no coating is provided is provided, whereby the metal thin plate can be easily fixed for temporary fixing by spot welding without affecting the conductivity. The spot-welded substrate protective material 15 is then fixed to the substrate 1 by sintering.

5A and 5B relate to another embodiment of the cutting tool of the present invention. FIG. 5A is a plan view of the cutting tool, and FIG. 5B is a cross-sectional view of FIG. The difference from the cutting tool 10 of FIG. 1 is that the substrate protective material 25 is filled in the recess 1 d formed in the substrate 1. As shown in FIG. 5, the depressions 1 d are formed in a number that fills the substrate protection material 25. The position of the recess 1d of the cutting tool 12 can prevent the strength of the substrate 1 from being lowered by making the position of the recess 1d on the front surface and the position of the recess 1d on the back surface inconsistent.
In the cutting tool 12, the recess 1d is filled with the metal bond as the base material 25a and the substrate protective material 25 in which the mixed amount of diamond as the abrasive grains 25b is uniformly mixed, and then fixed by sintering. The

A manufacturing method for fixing the substrate protective material 25 by providing the cutting tool 12 with the recess 1d will be described.
FIG. 6 is a flowchart for explaining the manufacturing method. As shown in FIG. 6, the first step is a step of forming a recess 1 d having a desired size and shape on the substrate 1. The processing method of the dent 1d may be, for example, counterbore with a drill or recess forming by press working. Furthermore, it may be a lamination of plates.
The second step is a step of filling the recess 1d with the substrate protective material 25 generated by adding abrasive grains to the metal bond. Here, the substrate protective material 25 is semi-solid and has fluidity. When the substrate protective material 25 is filled in the recess 1d, the upper surface of the substrate protective material 25 is set to be lower than the cutting edge portion 2.
The third step is a step in which the substrate 1 filled with the substrate protective material 25 is placed in a mold and pressed. The method for loading the mold is the same as that described with reference to FIG.
The fourth step is a step of sintering.
By performing these steps, it is possible to provide the cutting tool 12 to which the substrate protective material 25 is more firmly fixed.

FIG. 7 relates to another embodiment of the cutting tool of the present invention, and FIG. 7A is a plan view of the cutting tool 13. (B) is the sectional view, and (c) is an explanatory view showing the use situation.
As shown in FIG. 7 (a), the substrate protection member 35 is provided with a metal plate serving as a ring-shaped base formed corresponding to the shape of the slit groove 3, and a metal bond on the surface of the metal plate. And abrasive grains. The outer diameter φa indicating the outermost peripheral position of the substrate protective material 35 is determined by the inner diameter of the cutting edge portion 2, and the inner diameter φb indicating the innermost peripheral position of the substrate protective material 35 is determined by the disc grinder 30 shown in FIG. It depends on the position of the top 30a. The ring-shaped substrate protective material 35 is provided with relief according to the groove shape of the slit 3.

  The present invention can be variously modified and changed within the scope of the technical idea. For example, the shape of the substrate protection material 5 shown in FIG. 1 is not limited to a circle, and may be cut into a desired size, for example, a semicircle, an ellipse, a rectangle, a ring, and other various shapes. . Further, the shape of the recess formed in the substrate of the cutting tool may be various other shapes such as a semicircle, an ellipse, a quadrangle, a ring shape and the like.

(A) is a top view of the cutting tool which concerns on this invention, (b) is sectional drawing of (a), (c) is explanatory drawing which shows the usage form. It is a flowchart explaining the manufacturing method of the cutting tool which concerns on this invention. It is sectional drawing which shows the state which loaded the board | substrate to the carbon lower mold | type used when manufacturing the cutting tool which concerns on this invention, a middle mold | type, and an upper mold | type. (A) is a top view of the cutting tool which shows the other form which concerns on this invention, (b) is sectional drawing of (a). (A) is a top view of the cutting tool which shows the other form which concerns on this invention, (b) is sectional drawing of (a). It is a flowchart explaining the manufacturing method of the cutting tool which concerns on this invention. (A) is a top view which concerns on the cutting tool which shows the other form which concerns on this invention, (b) is the sectional drawing, (c) is explanatory drawing which shows the use condition. The conventional cutting tool is shown, (a) is a top view of a cutting tool, (b) is sectional drawing of (a). The conventional cutting tool is shown, (a) is a front view of a cutting tool, (b) is sectional drawing of the AA line shown to (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 1a Front surface 1b Back surface 1c Mounting hole 1d Depression 2 Cutting edge part 3 Slit groove 5, 15, 25, 35 Substrate protection material 5a, 15a, 25a Base material 5b, 15b, 25b Abrasive grain 6 Positioning pin 7 Lower mold 8 Medium mold 9 Upper mold 10, 11, 12, 13 Cutting tool (diamond cutter)
20 Cutting tool (diamond cutter)
21 Substrate 22 Cutting edge

Claims (4)

In a cutting tool provided with a cutting edge portion thicker than the substrate on the outer peripheral surface of the disk-shaped substrate,
A cutting tool characterized in that a substrate protective material is disposed on the front and back surfaces of the substrate, and the upper surface of the substrate protective material is set lower than the upper surface of the cutting blade portion.   2. The cutting tool according to claim 1, wherein the substrate protective material is composed of a base material fixed to the substrate and abrasive grains provided on an upper surface of the base material. A first step of forming a substrate protective material into a desired size and shape;
A second step of temporarily fixing the substrate protective material on the front and back surfaces of the substrate, and temporarily fixing a thicker cutting edge than the thickness of the substrate and the substrate protective material on the outer peripheral surface of the substrate;
A third step of loading the substrate protective material and the cutting edge portion into a substrate temporarily fixed and applying a press;
A fourth step of sintering the mold;
A cutting tool manufacturing method comprising: A first step of forming a recess of a desired size and shape on a substrate;
The substrate protective material generated by adding abrasive grains to the metal bond is filled in the recess, and a cutting edge portion having a thickness larger than the thickness of the substrate and the substrate protective material is temporarily fixed to the outer peripheral surface of the substrate. A second step of
A third step of loading the substrate with the cutting blade portion provided on the substrate on which the substrate protection material and the cutting blade portion are temporarily fixed, and applying a press;
A fourth step of sintering the mold;
A cutting tool manufacturing method comprising:

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