JP2003170358A - Cutting wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grinding wheel arranging soldering abrasive grains on a base plate in a layer capable of improving sharpness and providing a favorable cutting surface by improving a shape of a base plate outer peripheral part and arrangement of the abrasive grains. <P>SOLUTION: The abrasive grains 2 become less liable to fall as its holding force is increased by chamfering a crest part of an outer periphery of the base plate 1 of a cutting wheel 10 and arranging the abrasive grains 2 on this chamfered part 1c. Additionally, biting of the abrasive grains 2 into a cutting material is improved and sharpness is also improved by arranging the abrasive grains 2 on all steps so that all of them do not simultaneously make contact with the cutting material by diagonally arranging the abrasive grains 2 on each of the steps in a state of developing an outer peripheral surface 1a and the chamfered part 1c with the abrasive grains 2 arranged on them in the base plate peripheral direction or arranging the abrasive grains 2 of an either one of the steps by slipping them aside from the other abrasive grains 2. Furthermore, it is possible to prevent abrasion of a soldering material as the cutting material hardly makes contact with the soldering material by making an arranging interval L in the peripheral direction of the abrasive grains 2 an arranging position of which is slipped aside smaller than an abrasive grain diameter (d). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cutting wheel used for cutting concrete, concrete secondary products, cement-based building materials, ceramic-based building materials, and the like.
The present invention relates to a cutting wheel in which sharpness is improved by improving the arrangement of abrasive grains that are further arranged on a substrate by brazing.

[0002]

2. Description of the Related Art Concrete, secondary concrete products,
For cutting cement-based building materials, ceramic-based building materials and the like, a cutting wheel in which abrasive grains are further arranged by brazing on the outer peripheral portion of a disk-shaped substrate is used. Such a cutting wheel is required to have excellent sharpness and to maintain the sharpness stably for a long period of time. However, the cutting wheel deteriorates in sharpness and life as the cutting work progresses.

The main causes thereof are that the adhered state of the abrasive grains on the substrate is unstable and the abrasive grains are likely to fall off, the chip pocket is small, and the control of the abrasive grain interval is insufficient, so that during cutting work. It is possible that the chips cause clogging. Especially regarding the abrasive grain interval, it is difficult to arrange the abrasive grains in a predetermined arrangement state on the surface of the substrate, and in the portion where the abrasive grains are in close proximity to each other, cutting chips are difficult to be discharged, resulting in a decrease in sharpness. Connect

In manufacturing a cutting wheel by a brazing method, as a measure for uniformly dispersing abrasive grains, Japanese Patent Laid-Open No. 9-19867 discloses a method in which metal-coated diamond abrasive grains are used as a gap between a substrate outer peripheral surface and a die. A method for manufacturing a cutting wheel is disclosed, in which the silver brazing material is infiltrated and the substrate and the mold are heated and the silver solder is infiltrated into the gap. In addition, JP-A-10-118
Japanese Patent No. 937 describes a cutting wheel in which working abrasive grains are formed by a single layer of one or a plurality of superabrasive grains, and the distance between the working abrasive grains in the outer circumferential direction is equal to or larger than the grain size of the working abrasive grains. Has been done.

[0005]

According to the method disclosed in the above publication, a cutting wheel in which abrasive grains are uniformly distributed at a predetermined interval can be obtained. However, JP-A-9-19
In the cutting wheel described in Japanese Patent No. 867, an abrasive grain layer having a constant thickness determined by a gap between a substrate and a mold is formed, and a metal coating component of the abrasive grains and silver solder are filled between the abrasive grains. Since it is in the shape, so-called chip pockets are not formed, and there is a problem that sufficient sharpness and chip discharge cannot be obtained.

Further, the cutting wheel described in Japanese Patent Laid-Open No. 10-118937 has a small holding force for the abrasive grains at the ridges of the outer periphery of the substrate and is apt to fall off, and the gap between the abrasive grains is too large for cutting. There is a problem in that the vibration of the wheel and the chipping of the cut surface become large.

The problem to be solved by the present invention is to improve the sharpness by improving the shape of the outer peripheral portion of the substrate and the arrangement of the abrasive grains in a grinding wheel in which the abrasive grains are further arranged and brazed on the substrate. To get the cut surface. The abrasive grains referred to in the present specification include diamond abrasive grains, cBN abrasive grains, and abrasive grains in which these abrasive grains are metal-coated, a diamond sintered body, and a cBN sintered body, and these are collectively referred to. It is called abrasive grain.

[0008]

A cutting wheel according to the present invention is a cutting wheel in which abrasive grains are arranged in a single layer on an outer peripheral portion of a substrate and brazed, and a ridge portion on the outer peripheral portion of the substrate is chamfered.
Abrasive grains are arranged in the chamfered portion so as to protrude from the side surface of the substrate to form a group of three or more stages in the thickness direction of the substrate. It is characterized in that the disposition position and the disposition position of the abrasive grains of the abrasive grains in the other stages are made different from each other in the circumferential direction of the substrate with an interval equal to or smaller than the average grain size of the abrasive grains.

In the cutting wheel of the present invention, the ridges on the outer periphery of the substrate are chamfered, and the abrasive grains are arranged in the chamfered portions, whereby the holding force of the abrasive grains is increased in the chamfered portions and the abrasive particles are less likely to fall off. . Further, by disposing the abrasive grain groups of each stage having three or more stages in the substrate thickness direction so as not to be aligned in the substrate circumferential direction in the substrate thickness direction, the abrasive grains of all stages are At the same time, the material to be cut does not come into contact with the material to be cut into the material to be cut, and the sharpness is improved. In this case, if the circumferentially-arranged intervals of the abrasive grains, which are arranged at different positions, are larger than the average particle size of the abrasive grains, the material to be cut easily contacts the brazing material, and the abrasion of the brazing material increases.

Further, for the same reason as described above, an abrasive grain group of abrasive grains arranged on the outer peripheral side surface of the substrate at intervals in the radial direction and the circumferential direction of the substrate and an abrasive grain group arranged in the chamfered portion. At least 1 in each step abrasive grain group consisting of
It is also possible to make the abrasive grain arrangement position of the abrasive grain group of the stage and the abrasive grain arrangement position of the abrasive grain group of the other stage different from each other in the circumferential direction of the substrate with an interval not larger than the average grain size of the abrasive grains. it can. In this case, it is appropriate that the abrasive grains arranged on the side surface of the outer peripheral portion of the substrate be a group of two abrasive grains in the radial direction of the substrate. When the number of abrasive grains on the side surface of the outer peripheral portion of the substrate is three or more, chipping of the cut surface by the side surface abrasive grains increases.

Here, it is preferable that the width of the chamfered portion is equal to or larger than the average grain diameter of the abrasive grains and the inclination angle is equal to or larger than 30 degrees with respect to the side surface of the substrate. If the width of the chamfered portion is smaller than the average grain size of the abrasive grains, the abrasive grain holding force of the brazing material becomes insufficient and the abrasive grains are likely to fall off. If the angle of inclination of the chamfered portion is smaller than 30 degrees, the horizontal component of the adhesive surface at the time of cutting becomes large, and the load on the brazing material becomes large, leading to the dropping of abrasive grains. Also,
In brazing all the abrasive grains, it is appropriate that the amount of the abrasive grains embedded is 1/3 or more of the average grain size of the abrasive grains. If the embedding amount is less than 1/3 of the average grain size of the abrasive grains, the retaining force of the abrasive grains becomes insufficient.

The cutting wheel in which the abrasive grains are arranged on each surface of the outer peripheral portion of the substrate under specific conditions as described above can be manufactured as follows. The first method is to use a screen in which holes are regularly formed at predetermined intervals, apply an organic adhesive on each surface of the substrate periphery, and place abrasive grains on the organic adhesive. After the abrasive particles are temporarily fixed by drying in a drying oven, the mixture of the brazing material and the binder is applied only to the adhesive portion, and the particles are arrayed at predetermined intervals by heating and brazing to fix them permanently. Is the way. The second method is a method in which a mixture of a brazing material and a binder is applied using a screen, and heating is performed in a state where abrasive grains are arranged, so that the fixing is performed without temporary fixing. Temporary fixing of the abrasive grains from the standpoints of securely holding the abrasive grains and arranging the abrasive grains under predetermined arrangement conditions and controlling the coating amount of the mixture of the brazing material and the binder for forming the chip pocket. The first method is suitable because it can be surely applied to each abrasive grain later.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1A is a front view of a cutting wheel according to an embodiment of the present invention, and FIG.
FIG. 2 is a sectional view taken along line A, and FIG. 2 is an enlarged sectional view of the outer peripheral portion of the substrate. In the figure, the abrasive grains and the arrangement of the abrasive grains are schematically shown.

The cutting wheel 10 of this embodiment is a wheel for cutting concrete or cement-based building materials. The substrate 1 is a steel substrate having an outer diameter of 100 mm and a thickness of 1.2 mm, the abrasive grains 2 are diamond abrasive grains having an average grain size of 0.35 mm, and the brazing filler metal 3 is an Ag-Cu-Ti based active metal. Let's enter.

Slits 11 for discharging chips are formed on the outer periphery of the substrate 1, and abrasive grains 2 are arranged between the slits 11. As shown in the enlarged view of FIG. 2, the outer peripheral portion of the substrate 1 is chamfered at a ridge portion which is a boundary between the outer peripheral surface 1a and the outer peripheral side surface 1b to form a flat chamfered portion 1c. The width w of the chamfered portion 1c is about 1.7 times the abrasive grain size d, and the inclination angle θ is about 35 degrees.

The abrasive grains 2 are, as shown in FIGS. 1 and 2,
The outer peripheral surface 1a and the chamfered portion 1c of the substrate 1 are arranged in a row in the circumferential direction of the substrate, and the outer peripheral side surface 1b is arranged in two rows at intervals in the radial direction of the substrate. The embedding amount u of the abrasive grains 2 by the brazing material 3 is about 1/2 of the abrasive grain size d.

Next, the arrangement of the abrasive grains 2 will be described. 3 is a development view of a part of the outer peripheral surface 1a and the chamfered portion 1c of the substrate 1 viewed in the substrate circumferential direction, and FIG. 4 is a development view of a part of the outer peripheral surface 1b of the substrate 1 viewed in the substrate circumferential direction. .

In the cutting wheel 10 of this embodiment, the abrasive grains 2 are arranged in the chamfered portion 1c which is obtained by chamfering the ridge of the outer periphery of the substrate 1, so that the abrasive grains 2 arranged in the chamfered portion 1c are brazed. As a result, the holding force is increased, which makes it difficult to fall off. Further, the outer peripheral surface 1a on which the abrasive grains 2 are arranged and the chamfered portion 1c
Are arranged in the substrate circumferential direction in such a manner that the abrasive grain groups in each of the three stages in the substrate thickness direction are not aligned in the substrate circumferential direction in the substrate circumferential direction. Specifically, FIG.
As shown in (a) of the above, the abrasive grains of each step are arranged obliquely, or
Alternatively, as shown in FIG. 3 (b), one of the stages of abrasive grains may be arranged so as to be offset from the other grains so that the grains of all stages do not contact the material to be cut at the same time. Arrange. This improves the bite into the material to be cut and improves the sharpness. Further, the circumferentially arranged intervals L _{1 to} L ₅ of the abrasive grains, which are arranged at different positions, are made smaller than the abrasive grain size d so that the material to be cut is less likely to come into contact with the brazing material, and the brazing material is worn. To prevent.

Similarly, with the outer peripheral side surface 1b having the abrasive grains 2 and the chamfered portion 1c unfolded in the circumferential direction of the substrate, the abrasive grain groups of three stages in the substrate radial direction are arranged in the substrate circumferential direction. The installation positions are arranged so as not to be aligned in the radial direction of the substrate. Specifically, as shown in FIG. 4, one of the abrasive grains of the abrasive grain group arranged in three stages on the outer peripheral side surface 1b and the chamfered portion 1c is arranged so as to be offset from the other abrasive grains, and disposed so as not to abrasive stage contacts the workpiece at the same time, further, the circumferential direction arrangement interval L ₆ of abrasive grains shifting the arrangement _position, L
₇ is smaller than the abrasive grain size d.

The procedure for manufacturing the cutting wheel 10 is as follows. As the substrate 1, a steel substrate having an outer diameter of 100 mm and a thickness of 1.2 mm is prepared. As the abrasive grain 2, a diamond abrasive grain having an average particle size of about 350 μm is prepared. An organic adhesive is applied to the outer peripheral portion of the substrate 1 by using a screen in which holes having a diameter of 0.35 mm are arranged in the shape shown in FIGS. 3 and 4. -Place the abrasive grains 2 on this organic adhesive. In this state, the abrasive grains 2 are arranged on the outer peripheral portion of the substrate 1 in the form shown in FIGS. -This is dried in a drying furnace at 120 ° C for 1 hour to temporarily fix the abrasive grains. -Using a three-dimensionally movable applicator (discharging machine), a mixture of a brazing material and a binder is applied to the adhesion portion at a height of 1/2 of the abrasive grain size. -This is heated in a non-oxidizing atmosphere at 1000 ° C for 1 hour to permanently fix the abrasive grains to the base metal.

[Test Example] A cutting wheel was produced in which abrasive grains 2 were arranged on the outer peripheral portion of the substrate 1 molded as shown in FIG. 2 as shown in FIGS. 3 (a) and 4. Using the same abrasive grains as this cutting wheel (invention product), a cutting wheel (comparative product) in which the ridge of the outer periphery of the substrate is not chamfered was manufactured and a cutting processing test was conducted.

[Test conditions] Cutting machine: Hitachi circular saw C4YA1 Machine rotation speed: 13000 min ^-1 Material to be cut: Extrusion molding cement board Depth of cut: 15 mm / pass Cutting method: Dry cutting Feed rate: Load current 8 A To adjust

Table 1 shows the test results.

[Table 1] The cutting speed and the wheel life of the cutting wheel of the invention product are 100 times those of the cutting wheel of the comparative product.
It shows with the index when. As can be seen from the table, as compared with the cutting wheel of the comparative product in which the adhesion of the abrasive grains to the outer peripheral surface of the substrate is unstable, the abrasive particles are firmly adhered to the outer peripheral surface of the substrate and the chamfered portion, and the arrangement of the abrasive grains is further improved. The cutting wheel of the improved invention has a cutting speed improved by about 1.5 times and a grindstone life increased by about 1.8 times.

[0024]

The present invention has the following effects.

(1) By chamfering the ridges on the outer periphery of the substrate and disposing the abrasive grains in the chamfered portions, the holding force of the abrasive grains in the chamfered portions is increased, and the chamfered portions are less likely to fall off. Further, by disposing the abrasive grain groups of each stage having three or more stages in the substrate thickness direction so as not to be aligned in the substrate circumferential direction in the substrate thickness direction, the abrasive grains of all stages are At the same time, it does not come into contact with the material to be cut, and it becomes easier to cut into the material
Sharpness is improved.

(2) Similarly, in each stage abrasive grain group consisting of the side surface of the outer peripheral portion of the substrate and the abrasive grain group disposed in the chamfered portion, at least one stage of the abrasive grain group, and other positions By making the abrasive grain arrangement position of the abrasive grain group of the stage of the abrasive grains different from each other in the circumferential direction of the substrate at intervals equal to or less than the average grain size of the abrasive grains, the bite into the material to be cut is improved and the sharpness is improved. improves.

(3) By setting the width of the chamfered portion to be equal to or larger than the average grain diameter of the abrasive grains and the inclination angle to be equal to or larger than 30 degrees with respect to the side surface of the substrate, sufficient abrasive grain holding force can be obtained and the abrasive grains fall Hard to do.

[Brief description of drawings]

1A is a front view of a cutting wheel according to an embodiment of the present invention, and FIG. 1B is a sectional view taken along line AA of FIG.

FIG. 2 is an enlarged cross-sectional view of an outer peripheral portion of the substrate of FIG.

3 is a partially developed view of the outer peripheral surface of the substrate outer peripheral portion and the chamfered portion of FIG. 1. FIG.

FIG. 4 is a partial development view of the outer peripheral side surface of the substrate of FIG.

[Explanation of symbols]

Reference Signs List 1 substrate 1a outer peripheral surface 1b outer peripheral side surface 1c chamfered portion 2 abrasive grains 3 brazing material 10 cutting wheel 11 slit d abrasive grain diameter w chamfered portion width u abrasive grain embedding amount θ chamfered inclination angle L _{1 to} L ₇ grinding Grain spacing

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Seiya Ogata             210 Takeno, Odaiba, Ukiha-gun, Fukuoka             Noritake Diamond Co., Ltd. F-term (reference) 3C063 AA02 AB03 BB02 BB23 BB24                       BC02 BG03 BG07 CC09 EE16                       FF22 FF23

Claims (3)

[Claims] 1. A cutting wheel in which abrasive grains are further arranged and brazed on an outer peripheral portion of a substrate, and a ridge portion on the outer periphery of the substrate is chamfered, and the chamfered portion is provided with abrasive grains so as to protrude from a side surface of the substrate. Arranged to form a group of three or more abrasive grains in the thickness direction of the substrate, and at least one stage of each stage has at least one stage of abrasive grains arranged and the grains of another stage. A cutting wheel characterized in that the disposition position is different in the circumferential direction of the substrate with an interval of not more than the average grain size of abrasive grains. 2. A stepped abrasive comprising an abrasive grain group of abrasive grains disposed on the outer peripheral side surface of the substrate at intervals in the radial direction and the circumferential direction of the substrate and an abrasive grain group disposed in the chamfered portion. Among the particle groups, at least one stage of the abrasive grain group and the other stage of the abrasive grain group are arranged at different positions in the circumferential direction of the substrate at intervals less than or equal to the average grain size of the abrasive grains. The cutting wheel according to claim 1, 3. The cutting wheel according to claim 1, wherein a width of the chamfered portion is equal to or larger than an average grain diameter of abrasive grains, and an inclination angle is equal to or larger than 30 degrees with respect to a side surface of the substrate.