JPH04223871A - Diamond grinding wheel and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a grinding wheel excellent in a grinding efficiency, by forming a thermal sprayed abrasive grain layer that the diamond abrasive grain subjected to a metal coating is held with its dispersion in a metal binder, excepting the part of holes, on the shoe provided with holes and recesses. CONSTITUTION:A mixing power 8 mixed with the diamond abrasive grain subjected to a metal coating and a metal binding powder is subjected to a plasma spraying, in the state of a separate shoe 6 being superposed at the opposite side, onto the shoe 2 provided with a hole 4 and recess 5. Consequently a thermal spray abrasive grain layer 3 that the diamond abrasive grain subjected to a metal coating is held with its dispersion in a metal binder is formed, excepting the part of the hole 4, and a desired diamond grinding wheel 1 is obtained.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diamond grindstone used for chamfering stones, cutlery tools, lapping machines, etc., and a method for manufacturing the same.

0002

BACKGROUND OF THE INVENTION For example, a disc-type diamond grindstone is used as a grindstone for chamfering stone materials, in which diamond abrasive grains are fixedly held on the surface of a base metal by metal bonding or electrodeposition. Generally, in order to improve the grinding performance of a grindstone for difficult-to-cut materials, it is important to increase the cooling capacity of the grinding surface and promote the escape of grinding debris. For this reason, the presence of pores (chip pockets), which create cooling water pools and escape areas for grinding debris, plays a very important role.

0003

[Problem to be solved by the invention] Therefore, as a measure to actively add chip pockets to a diamond grinding wheel,
It has been proposed to make a punched metal by making holes here and there in advance in the base metal, and to form an abrasive grain layer with holes thereon. In this way, it is expected that the punched hole will serve as a macroscopic chip pocket, and that the edge effect caused by the protrusion of the abrasive grains around the punched hole will increase the grinding efficiency.

However, it is technically difficult to form an abrasive grain layer with a uniform thickness on the surface of such a base metal with holes, and in addition, in order to maintain a certain strength of the base metal, it is necessary to There is also a limit to the aperture ratio of the holes.

[0005] The present invention further increases the aperture ratio of the base metal, which essentially functions as a chip pocket, by providing a recessed hole as well as a punched hole in the base metal, and combining this with a method of forming an abrasive layer by thermal spraying. The present invention aims to provide a new diamond grindstone that can be increased in size, and also provides a suitable manufacturing method thereof.

[0006]

[Means for Solving the Problems] That is, the diamond abrasive wheel according to the present invention has diamond abrasive grains coated with metal on a base metal provided with a punched hole and a recessed hole, except for the punched hole portion. It consists of a layer of sprayed abrasive grains that are dispersed and held in the abrasive grains.

[0007] In addition, as a manufacturing method of this diamond grinding wheel, metal-coated diamond abrasive grains and metal binder powder are stacked on a base metal with punched holes and a separate base metal on the opposite side. A method is adopted in which a mixed powder is plasma sprayed to form a sprayed abrasive grain layer in which metal-coated diamond abrasive grains are dispersed and held in a metal binder, except for the hole area. .

[0008]

[Function] In the diamond grinding wheel according to the present invention, a punched hole and a recessed hole are provided in the base metal, and the recessed hole is uniformly coated with a sprayed abrasive grain layer that disperses and holds diamond abrasive grains following the shape of the recessed hole. Ru. In a grindstone equipped with these recessed holes, each recessed hole serves as a chip pocket that stores cooling water or releases grinding debris, and also produces an edge effect due to the protrusion of the abrasive grains around the recessed hole. Thus, an effect similar to that of substantially doubling the aperture ratio of punched holes while maintaining the strength of the base metal can be obtained.

Furthermore, according to the manufacturing method of the present invention, when a sprayed abrasive grain layer is formed by plasma spraying on a base metal with a punched hole, a layer of thermally sprayed abrasive grains is simultaneously formed on a separate base metal stacked on the opposite side. The sprayed abrasive grain layer is formed through the punched hole part, which avoids wasteful consumption of diamond abrasive grains, and also allows the base metal with the punched hole and the separate base metal to be sprayed using this base metal as a mask. A sprayed abrasive grain layer is formed on the gold at the same time.

0010

[Example] Hereinafter, an example will be explained with reference to the drawings.

FIGS. 1 and 2 show a specific example of a diamond grindstone according to the present invention.

In the figure, reference numeral 1 indicates a disc-shaped diamond grinding wheel, and a metal base 2 made of iron, aluminum alloy, etc.
A sprayed abrasive grain layer 3 is formed thereon with a substantially uniform thickness. In the case of a typical product, the wall thickness of the base metal 2 is B2; 1 to 2
mm, and the build-up thickness B3 of the abrasive grain layer 3 is formed to be 0.5 to 1 mm.

The base metal 2 is pre-drilled with punch holes 4 distributed radially on the circumference by press working or the like at an appropriate aperture ratio, and holes 4 are formed between adjacent punch holes 4. Spherical recessed holes 5 are provided in a staggered manner at the positions shown in FIG. 1 by machining using a ball end mill or the like.

[0014] As for the hole 4, of course, the abrasive layer 3
is missing. On the other hand, in the area of the recessed hole 5, the abrasive grain layer 3 is formed to have a thickness substantially equal to that of the surface of the base metal 2, following the shape of the recess. In the case of a typical product, the punched hole diameter is φ4; 3.5 mm, and the recessed hole diameter is φ5; 3.
．． They are provided with the same diameter size of 5mm. However, after forming the sprayed abrasive layer 3, the edge of each recessed hole 5 is also coated with the abrasive layer 3, so the size of the recessed hole 5 is slightly smaller than the size of the punched hole 4 in terms of appearance. It will appear.

The sprayed abrasive grain layer 3, which is formed almost uniformly on the surface of the base metal 2 except for the punched holes 4, is made of diamond abrasive grains (not shown) coated with a metal such as Ni or Cu.
is dispersed in a metal binder such as Ni, Co, Cu, Cu-Sn, or W (or may contain aggregate abrasive grains of carbide such as WC or SiC or oxide powder such as alumina as necessary). The metal bond of the sprayed abrasive grain layer has good wettability (retention force) with respect to the diamond abrasive grains, and the adhesion of the sprayed abrasive grain layer to the base metal is high. It has the characteristic that it can be coated uniformly by following the shape of the recess.

The means for forming this sprayed abrasive grain layer will be described in detail in Japanese Patent Application No. 2-274414 and later in Examples relating to the manufacturing method.

Thermal sprayed abrasive grains are formed by holding metal-coated diamond abrasive grains dispersed in a metal binder on the base metal 2 provided with the punched holes 4 and the recessed holes 5, except for the punched holes 4. In the diamond grinding wheel 1 on which the layer 3 is formed, the chip pocket forming effect of the recessed hole 5 is superimposed on the chip pocket forming effect of the punched hole 4, and thereby the function of collecting cooling water and discharging grinding debris, and further In addition to the surface pressure reinforcement effect due to the edge effect around the punched hole 4 and the recessed hole 5, characteristics with extremely excellent grinding efficiency are exhibited. Moreover, by providing the punch hole 4 and the recessed hole 5, the punch hole 4
It is possible to provide a high aperture ratio over almost the entire surface of the base metal 2, which is not possible with the base metal 2 alone.

Next, an embodiment of the method for manufacturing the above-mentioned diamond grindstone will be described.

When forming a sprayed abrasive grain layer on a base metal with punched holes, if the aperture ratio is large, the diamond abrasive grains sprayed from the thermal spray gun onto the base metal as a mixed powder with metal binder powder will be removed. It is recognized that there is a problem in which a large amount of loss is wastefully dissipated through the hole. Therefore, we stacked a separate base metal on the opposite side of the base metal with the punched hole, masked it with the base metal with the punched hole, and simultaneously formed a sprayed abrasive grain layer on the other base metal. A method is proposed.

FIG. 3 shows an outline of this manufacturing method, and shows the base metal 2 (recessed hole 5
), a separate base metal 6 is stacked on the side opposite to the surface on which the abrasive grain layer is formed, and in this state the abrasive grain layer 3 is deposited by plasma spraying from a thermal spray gun 7. .

The abrasive layer forming surfaces of the superimposed base metal 2 and base metal 6 are subjected to a surface treatment such as blasting in advance, and a thermal spray gun 7 is applied as disclosed in Japanese Patent Application No. 2-274414. Then, a mixed powder 8 of metal-coated diamond abrasive grains, metal binder powder, etc. is plasma sprayed. At this time, the thermal spraying gun 7 is moved back and forth as shown by the arrow in the figure to uniformly form the thermal spraying abrasive grain layer 3 on the base metal 2.

[0022] With this, the punch hole 4 is formed on the base metal 2.
A sprayed abrasive grain layer 3 in which diamond abrasive grains are dispersed and held in a metal binder is formed to a substantially uniform thickness over the entire area including the recessed hole 5 part, except for the part shown in FIG. Mask spraying using the base metal 2 as a mask is also performed on the base metal 6 that has been coated. That is, the sprayed abrasive grain layer 9 is similarly formed in a dispersed state corresponding to the hole 4 of the base metal 2.

FIGS. 4 and 5 show the correspondence between the sprayed abrasive layer 3 formed on the base metal 2 and the sprayed abrasive layer 9 formed on the base metal 6 by masking the base metal 2. It shows.

That is, the base metal 2 on the front side which also serves as a mask
The sprayed abrasive grain layer 3 is formed with a desired thickness over the entire area including the recessed hole 5 (not shown) except for the punched hole 4, and on the other hand, the punched hole 4 of the base metal 2 is formed on the base metal 6 on the back side. The sprayed abrasive grain layer 9 of the mixed powder 8 that passes through and is laminated is formed in a dispersed state corresponding to the distribution of the punch holes 4 of the mask base metal 2.

Therefore, according to this manufacturing method, the punch hole 4
Punch holes 4 when forming the sprayed abrasive grain layer 3 on the base metal 2 provided with
There is no wastage of diamond abrasive grains passing through the diamond abrasive grains, and the diamond abrasive grain layer 3 is formed entirely on the base metal 2 having punched holes 4. It is possible to manufacture the diamond grindstone at the same time as the diamond grindstone.

[0026] Regarding the latter grindstone obtained by the above manufacturing method, each abrasive grain layer 9 is independently dispersed, so it is recognized that the edge effect is particularly large, and it is suitable for heavy grinding with high surface pressure, for example. It has been confirmed that it exhibits extremely excellent grinding performance for various purposes.

FIG. 6 shows an applied product of this new type of grindstone, in which the gaps between the sprayed abrasive grain layer 9, which is dispersed and formed on the base metal 6, are filled with, for example, GC abrasive grains (green carbon) and resin. The dressing layer 10 made of a mixed layer is embedded almost flush with the dressing layer 10 . In this way, it is possible to create a new diamond grindstone with a dressing material that has high grinding efficiency.

[0028]

[Effects of the Invention] As described above, in the diamond grinding wheel of the present invention, metal-coated diamond abrasive grains are dispersed in a metal binder in the base metal having punched holes and recessed holes, except for the punched hole portions. Since a sprayed abrasive grain layer is formed and held, the effect of forming chip pockets by the punched holes and the recessed holes is synergistically expressed, and a grindstone with extremely excellent grinding efficiency is realized.

Further, according to the manufacturing method of the present invention, a mask thermal spraying method is adopted in which a separate base metal is superimposed on the opposite side of the base metal with a punched hole and then thermally sprayed. Therefore, the sprayed abrasive grain layer can be formed on the base metal with punched holes without loss of expensive diamond abrasive grains, and the sprayed abrasive grain layer is dispersed and formed on the base metal together with this diamond grindstone with punched holes. Another new and useful diamond grinding wheel can be manufactured at the same time.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the invention.

FIG. 1 is a plan view of a diamond grindstone provided with punched holes and recessed holes.

FIG. 2 is a sectional view taken along the line AA in FIG. 1;

FIG. 3 is a cross-sectional view showing an example of the manufacturing method.

FIG. 4 is a partial cross-sectional view and a plan view of a diamond grindstone provided with punched holes.

FIG. 5 is a partial cross section and a plan view of a diamond grindstone manufactured by mask spraying.

FIG. 6 is a sectional view showing an applied product of a diamond grinding wheel manufactured by mask spraying.

[Explanation of symbols]

1 Diamond whetstone 2 Base money 3 Sprayed abrasive layer 4 Punch hole 5 Recessed hole 6 Base money 7 Thermal spray gun 8 Thermal spray mixed powder 9 Sprayed abrasive layer 10 Dressing layer

Claims (2)

[Claims] [Claim 1] A sprayed abrasive grain layer in which metal-coated diamond abrasive grains are dispersed and held in a metal binder is formed on a base metal having punched holes and recessed holes, except for the punched hole portions. A diamond whetstone characterized by: [Claim 2] A mixed powder of metal-coated diamond abrasive grains and metal binder powder is heated using plasma on a base metal with punched holes and a separate base metal stacked on the opposite side. A method for manufacturing a diamond whetstone, which comprises thermal spraying to form a sprayed abrasive grain layer in which metal-coated diamond abrasive grains are dispersed and held in a metal binder except for the punched hole portions.