JPH11239976A - Vitrified super abrasive whetstone - Google Patents

Abstract

(57) [Summary] To provide a vitrified superabrasive grindstone that allows an operator to easily determine the time to replace a grindstone with the naked eye without interrupting a grinding operation. SOLUTION: A grindstone segment 2 formed by integrally forming and firing a superabrasive grain layer 4 and an underlayer 5 is fixed to a peripheral surface or an end face of a disc-shaped base 1 by a vitrified superabrasive grindstone. In addition, the shape of the boundary between the superabrasive grain layer 4 and the underlayer 5 in the cross section passing through the axis of the grinding wheel segment 2 is different from the cross sectional shape of the grinding wheel working surface 2a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vitrified superabrasive grindstone in which a grindstone segment comprising a vitrified grindstone layer is fixed to an outer peripheral surface or an end surface of a disk-shaped base, and in particular, it is easy to judge a replacement time thereof. Technology to enable.

[0002]

2. Description of the Related Art As a vitrified superabrasive grinding wheel of this type, the one disclosed in, for example, Japanese Utility Model Laid-Open Publication No. 2-63964 is known as one which can easily determine the replacement time.

[0003] In this method, a super-abrasive layer is formed into a segment shape, fired, and then fixed to the outer peripheral surface of a disk-shaped base. As the wear of the grindstone progresses, the remaining amount display groove becomes shallower, so that the replacement time of the grindstone can be easily determined by checking the depth of the remaining amount display groove.

[0004]

However, in the above-described vitrified superabrasive grindstone based on the remaining amount indicating groove method, the processing for forming the remaining amount indicating groove is difficult because the superabrasive layer is very hard. However, there is a problem that the production cost of the grinding wheel itself rises.

[0005] In addition, there is a possibility that the grinding wheel segments may be damaged like a crack during the operation for forming the remaining amount indicating groove, and therefore, the grinding wheel may be damaged during the grinding operation. There was also.

Further, since the remaining display grooves are provided only at several places at the end of the grinding wheel, the remaining amount cannot be confirmed while the grinding wheel is kept rotating.
Therefore, in order to check the depth of the remaining amount indicating groove, the grinding operation must be interrupted and the rotation of the grinding wheel must be stopped, which is inefficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is a vitrified superabrasive grain that allows an operator to easily determine the time to replace a grinding wheel with the naked eye without interrupting the grinding operation. The purpose is to provide a whetstone.

[0008]

In order to achieve the above object, a vitrified superabrasive grindstone according to claim 1 comprises a whetstone segment formed by integrally forming a superabrasive layer and a base layer and firing the same. In the vitrified superabrasive grindstone fixed to the outer peripheral surface or the end surface of the disk-shaped base, the shape of the boundary line between the superabrasive layer and the underlayer in the cross section passing through the axis of the grindstone segment is It is characterized in that it has a shape different from the cross-sectional shape of the grinding wheel working surface.

That is, when the superabrasive layer and the underlayer are integrally formed, the cross-sectional shape of the boundary between them is formed so as to be different from the cross-sectional shape of the working surface of the grindstone. Bake. After the firing, the grinding wheel segments are arranged in a row on the outer peripheral surface or the end surface of the disk-shaped base, and fixed by a method such as bonding to complete a grinding wheel.

In such a grindstone, if the grindstone is consumed while repeating the grinding operation and the truing operation, an underlayer appears on a part of the work surface of the grindstone. The superabrasive layer is generally black or dark gray, while the underlayer has a distinctly different color from the superabrasive layer, such as white, light brown or pink. For this reason, even while the grinding wheel is rotating, it is possible to determine from the change in the color of the grinding wheel working surface that the operator is close to replacing the grinding wheel with the naked eye.

In the present invention, the shape of the boundary line between the superabrasive layer and the underlayer is not particularly limited, and the shape of the underlayer protruding toward the working surface of the grindstone at an end thereof may be mentioned. Can be.

A vitrified superabrasive grinding wheel according to a third aspect of the present invention is a grinding wheel wider than a workpiece, and passes through an axis in a vitrified superabrasive wheel used for performing plunge grinding. The shape of the boundary line between the superabrasive layer and the underlayer in the cross section is such that the portion that does not act on the processing protrudes toward the grinding wheel working surface.

In such a grindstone, if the grindstone is consumed while repeating the grinding operation and the truing operation, an underlayer appears on a portion of the work surface of the grindstone that is not acting on the processing. The superabrasive layer is generally black or dark gray, while the underlayer has a distinctly different color from the superabrasive layer, such as white, light brown or pink. For this reason, even while the grinding wheel is rotating, it is possible to determine from the change in the color of the grinding wheel working surface that the operator is close to replacing the grinding wheel with the naked eye.

In the present invention, the shape of the portion of the boundary line between the superabrasive grain layer and the underlayer which does not act on the processing is not particularly limited. And a shape protruding from the surface.

[0015]

According to the first and second aspects of the present invention,
The shape of the boundary line between the superabrasive layer and the underlayer in the cross section passing through the axis of the grinding wheel segment was made different from the shape of the working surface of the grinding wheel. This can be easily determined by the operator with the naked eye.

In this case, since the grinding wheel can be identified while being rotated, there is no need to interrupt the grinding operation, and it is possible to efficiently determine the grinding wheel replacement time.

Further, since it is not necessary to perform a processing operation such as forming a groove after firing the grindstone segments, there is no fear of damaging the grindstone segments, and the safety is further improved.

According to the third to fifth aspects of the present invention, in addition to the effects obtained by the first and second aspects of the present invention, the underlayer appears on the working surface of the grinding wheel in a portion that does not act on the processing of the workpiece. By monitoring the time, it is possible to determine the replacement time of the grindstone, so that the replacement time of the grindstone can be determined without adversely affecting the quality of the machined surface.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. First Embodiment FIG. 1 is an overall perspective view showing a first embodiment of a vitrified superabrasive grindstone of the present invention, FIGS. 2 and 3 are cross-sectional views of a whole grindstone showing a modified example of the same embodiment, and FIG. FIG. 5 is a perspective view showing a grinding wheel segment according to the same embodiment, and FIG. 5 is a cross-sectional view showing a process in which a superabrasive layer is consumed with wear of the grinding wheel.

First, the structure of the vitrified superabrasive grindstone of this embodiment will be described. As shown in FIG. 1, a plurality of grindstone segments 2 are formed on the outer peripheral surface of a disc-shaped base 1.
Are arranged and fixed in tandem. In the following description, a grindstone having the shape shown in FIG. 1 is used, but a grindstone for angular grinding as shown in FIG. 2 or a cup-type grindstone as shown in FIG. Good.

As shown in FIG. 4, the grinding wheel segment 2 is made of diamond or CBN (cubic boron nitride).
The superabrasive layer 4 mainly composed of superabrasive grains and vitrified as a binder, and the underlayer 5 mainly composed of abrasive grains such as ceramics are formed integrally and then fired.

The superabrasive layer 4 is generally black or dark gray, whereas the underlayer 5 has a distinctly different color from the superabrasive layer, such as white, light brown or pink. , Both are easily identifiable with the naked eye.

The boundary line Cb between the superabrasive layer 4 and the underlayer 5 has a shape different from the cross-sectional shape Ca of the grinding wheel working surface 2a.

FIG. 5 shows a process in which the superabrasive layer 4 is consumed in such a superabrasive grindstone with the wear of the grindstone.
This will be described with reference to FIG.

In the initial stage of using the grindstone, as shown in FIG. 5A, the superabrasive layer 4 has a sufficient thickness. However, if the grinding work is continued, the wear due to the processing and the wear due to the truing work will eventually cause the problem shown in FIG.
As shown in (b), the thickness of the superabrasive layer 4 decreases,
The grindstone working surface 2a gradually retreats.

When the grinding operation is further continued, the boundary Cb between the superabrasive grain layer 4 and the underlayer 5 is different from the cross-sectional shape Ca of the grinding wheel working surface 2a. As shown in (1), the underlayer 5 finally appears on a part of the grindstone working surface 2a.

Therefore, by monitoring the change in the color of the grinding wheel working surface 2a, it can be confirmed that the thickness of the usable superabrasive layer 4 is reduced and the time for replacement of the grinding wheel is approaching. It is easily determined by the naked eye of the operator.

As described above, in the vitrified superabrasive grindstone of the present embodiment, when the remaining amount of the superabrasive grain layer 4 decreases, the base layer 5 appears on a part of the grindstone working surface 2a. Monitoring by the operator makes it possible to easily determine with the naked eye that the time for replacement of the whetstone is imminent.

Second Embodiment Next, a vitrified superabrasive grindstone according to a second embodiment will be described with reference to FIGS. FIG. 6 is a cross-sectional view of a principal part showing a second embodiment of the vitrified super-abrasive grindstone of the present invention, FIG. 7 is a cross-sectional view showing a state of processing a workpiece with the vitrified super-abrasive grindstone of the same embodiment, and FIG. It is principal part sectional drawing which shows the modification of the same embodiment.

In the grindstone segment used in the vitrified superabrasive grindstone of the present embodiment, the shape of the boundary line Cb between the superabrasive grain layer 4 and the underlayer 5 is different from the cross-sectional shape Ca of the grindstone working surface 2a. It is shaped.

As shown in FIG. 7, the width of the vitrified superabrasive grindstone is wider than the processing surface Wa of the workpiece W to be processed. Further, the boundary line Cb between the superabrasive grain layer 4 and the underlayer 5 is shaped such that the underlayer 5 projects toward the grindstone working surface 2a at both ends where it does not act during processing.

When such a grindstone is used, if the grindstone is worn out by performing the truing operation, the underlayer 5 appears at both end portions of the grindstone work surface 2a as in the first embodiment. Therefore, by monitoring the change in color at both ends of the grinding wheel working surface 2a, the fact that the thickness of the usable superabrasive layer 4 is reduced and the grinding wheel replacement time is approaching, even if the grinding wheel is rotating, It is easily determined by the naked eye of the operator.

As described above, in the vitrified superabrasive grindstone of the present embodiment, when the remaining amount of the superabrasive grain layer 4 decreases, the underlayer 5 appears at both ends of the grindstone working surface 2a. Monitoring by the person makes it possible to easily determine with the naked eye that the time to replace the whetstone is imminent.

Incidentally, in the present embodiment, the shape of the boundary line Cb between the superabrasive grain layer 4 and the underlayer 5 in the cross section passing through the axis of the grinding wheel segment 2 is tapered as shown in FIG. Is also good.

The embodiments described above are described for the purpose of facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

[Brief description of the drawings]

FIG. 1 is an overall perspective view showing a first embodiment of a vitrified superabrasive grindstone of the present invention.

FIG. 2 is a cross-sectional view of the entire grindstone showing a modification of the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the entire grindstone showing another modification of the first embodiment of the present invention.

FIG. 4 is a perspective view showing a grinding wheel segment according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a process in which the superabrasive layer is consumed with wear of the grindstone in the first embodiment of the present invention.

FIG. 6 is a cross-sectional view of a principal part showing a second embodiment of a vitrified superabrasive grindstone of the present invention.

FIG. 7 is a cross-sectional view illustrating a state where a workpiece is machined with a vitrified superabrasive grindstone according to a second embodiment of the present invention.

FIG. 8 is a sectional view of a main part showing a modification of the second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base 2 ... Whetstone segment 2a ... Whetstone work surface 3 ... Adhesive 4 ... Super abrasive layer 5 ... Underlayer W ... Workpiece

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B24D 7/06 B24D 7/06

Claims (5)

[Claims] 1. A vitrified superabrasive grindstone in which a grindstone segment formed by integrally forming and sintering a superabrasive grain layer and a base layer is fixed to an outer peripheral surface or an end face of a disk-shaped base. A vitrified superabrasive grinding wheel, wherein a shape of a boundary line between the superabrasive layer and the underlayer in a section of the segment passing through an axis is different from a sectional shape of a working surface of the grinding wheel. 2. The boundary line between the superabrasive layer and the underlayer has a shape in which the underlayer protrudes toward the working surface of the grinding wheel at an end thereof. Vitrified super abrasive whetstone. 3. A vitrified superabrasive grindstone for plunge grinding formed wider than a workpiece, wherein a boundary line between the superabrasive grain layer and the underlayer in a cross section passing through an axis of the grindstone segment. 2. A vitrified superabrasive grinding wheel according to claim 1, wherein a portion of said shape that does not act on machining is a shape protruding toward the working surface of the grinding wheel. 4. The vitrified super-structure according to claim 3, wherein a portion of the boundary line between the superabrasive layer and the underlayer, which does not act on the processing, has a step-like shape. Abrasive whetstone. 5. The vitrified super-structure according to claim 3, wherein a portion of the boundary line between the superabrasive layer and the underlayer that does not act on the processing has a tapered shape. Abrasive whetstone.