JPS6225333Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement in a grinding wheel suitable for use when a large amount of machining is required in precision grinding.

As shown in Fig. 1, a grinding wheel 1 generally used for precision grinding is disc-shaped, and its outer peripheral surface forms a grinding surface 2, and this grinding surface 2 has the required accuracy over its entire axial length. It is made up of a finishing whetstone 3 with a grain size necessary to produce the desired results, and is formed into a cylindrical surface with a constant diameter. Now, using this grinding wheel 1, as shown in FIG.
A case in which surface grinding is performed will be described. FIG. 3 is a diagram in which crossfeeding has been performed once, and shows the remaining cutting amount R11 due to wear of the grindstone. Figure 4 is the same twice, Figure 5 is the same 3 times.
These are diagrams when crossfeeding is performed twice, and S1, S2, and S3 in these diagrams represent the ground surfaces created by superimposing one crossfeed S, and these grinding surfaces S1, S2, and
3 moves relative to the workpiece W each time the crossfeed is repeated, as a model divided by dashed-dotted lines. These third
In FIGS. 5 to 5, a11, a12 and a
13 is the effective depth of cut of the workpiece W by the grinding surface S1, and a21 and a22 are also the grinding surface S
2, the effective depth of cut a31 is also the effective depth of cut due to the grinding surface S3, and by further repeating the crossfeed, the total effective depth of cut (a1
1+a21+a31+...) reaches the set depth of cut a, and the workpiece W is machined to the required dimensions. The reason for this type of machining is that the grinding surface 2 is worn out as described above. Thus, grinding wheel 1
The shape of the grinding wheel 1 when the feed is performed reciprocatingly is 6th because the outer surface bears a larger amount of grinding.
As shown in the figure, the central part is convex. In the figure, the grinding wheel 1 is modeled to wear out in a stepwise manner, but in many cases, due to feed errors in the crossfeed, etc., the central part becomes a convex curved surface, and the workpiece W will be finished off by the top of the curved surface which is finally convex. However,
The grinding wheel 1 can process the workpiece W with higher precision if the top thereof is flat and not sharp.

The present invention has been made based on the above-mentioned circumstances.
The second wheel for rough finishing has better wear resistance than the grinding wheel part of
The grinding wheel portions of the grinding wheel are integrally connected, and the first grinding wheel is formed into a truncated conical shape with a portion adjacent to the second grinding wheel having a large-diameter bottom surface, thereby creating a grinding wheel that can achieve accuracy even when the amount of grinding is increased. It is something.

Hereinafter, the present invention will be described based on examples with reference to the drawings.

As shown in FIG. 7, the grinding wheel 10 includes a first grinding wheel portion 11 for finishing in the shape of a disk, and grinding wheels having the same shape integrally connected to both sides of the first grinding wheel portion 11. Second grindstone section 12, 12 for finishing
These first and second grindstone parts 11, 12,
The outer peripheral surface of 12 forms a grinding surface 13. The first grindstone section 11 is composed of a diamond grindstone, a CBN grindstone, a normal finishing grindstone (Al ₂ O ₃ , SiC), etc. suitable for finishing. 2nd above
The whetstone parts 12, 12 are diamond whetstones or
It is a CBN grindstone, which has a coarser grain size than the first grindstone part 11, has excellent wear resistance, and is suitable for rough finishing. Further, the second grinding wheel parts 12, 12 have an inclined outer circumferential surface having an inclination angle of θ, θ by making the diameter of the outer surface sides 14, 14 smaller than the diameter of the parts 15, 15 connected to the first grinding wheel part 11. 16,
16 is formed. That is, the rough finishing whetstone 12 is formed into a truncated conical shape with a large-diameter bottom surface adjacent to the finishing whetstone 11. This inclination angle θ is the grindstone width B,
The value is determined by the workpiece width C, the set depth of cut a, and one crossfeed S (indicated by a dashed line). Note that S1, S2, and S3 represent the grinding surfaces created by one superimposition of the crossfeed S, and the figure shows the case where the grinding wheel 10 is fed back and forth in the left and right direction. . Further, the width of the second grindstone portions 12, 12 in the feeding direction is set to be larger than the value of the cross feed S described above.

In the above-described configuration, when surface grinding is performed on the workpiece W with a set depth of cut a and a crossfeed S, the grinding surface 1 of the second grinding wheel portions 12, 12
3 is formed with inclined outer circumferential surfaces 16, 16 having an inclination angle θ, the portion of the set cutting depth a that is borne by the grinding surface S1 decreases, and the grinding surface S1
The amount of grinding decreases, and this decrease is borne by the ground surface S2 and below, making it possible to increase the set depth of cut a accordingly. In addition, since the second whetstone parts 12, 12 are made of abrasive grains that are suitable for rough finishing with excellent wear resistance and a large amount of coarse grinding than the first whetstone part 11, the second whetstone parts The amount of grinding by the parts 12, 12 is greater than the amount of grinding by the first grindstone part 11, so that the amount of grinding borne by the first grindstone part 11 can be reduced. moreover,
an inclined outer circumferential surface 16 that is not stepped but a continuous inclined surface;
16 has the effect that the crossfeed can be set arbitrarily. In addition, for the grinding wheel 1 used for processing in which the feeding of the grinding wheel 1 is not carried out reciprocally but only in one direction, the second grinding wheel section 12 is not necessarily connected to both sides of the first grinding wheel section 11, but only on one side. You can.

As detailed above, the present invention integrates a finishing whetstone and a rough finishing whetstone, which has better wear resistance than the finishing whetstone, so that the rough finishing whetstone is applied to the workpiece before the finishing whetstone. High efficiency grinding (heavy grinding) and precision finishing grinding can be performed simultaneously with the same grinding wheel by continuously contacting the finishing whetstone. Due to the large-diameter slope, the amount of grinding at the beginning of contact is reduced, and this combined with the fact that the rough-finishing wheel, which has excellent wear resistance, comes into contact first, results in a greater amount of grinding resulting in lower accuracy. I was able to use it as a grinding wheel.

Furthermore, there is an effect that any crossfeed can be taken.

Note that the grinding wheel of the present invention can be used not only for surface grinding but also for other grinding methods such as cylindrical grinding. Furthermore, it goes without saying that the grinding wheel of the present invention is not limited to the embodiments, and that various changes in its structure, composition, etc. can be made without departing from the spirit of the invention.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway sectional view of a conventional grinding wheel;
6 to 6 are explanatory diagrams of a surface grinding process using a conventional grinding wheel, and FIG. 7 is a partially cutaway sectional view of an embodiment of the grinding wheel of the present invention. 10... Grinding wheel, 11... First grinding wheel part (finishing whetstone), 12... Second grinding wheel part (rough finishing whetstone), 1
3...Grinded surface, 14...Outer side, 15...
...Portion connected to the first grindstone portion, 16... Inclined outer circumferential surface, W... Workpiece.

Claims (1)

[Scope of utility model registration request] In a grinding wheel consisting of a plurality of grinding wheels whose outer circumferential surface is a grinding surface, a finishing grinding wheel and a rough finishing grinding wheel having better wear resistance than the finishing grinding wheel are integrally provided, and the rough finishing grinding wheel is adjacent to the finishing grinding wheel. A grinding wheel characterized by having a truncated conical shape with a large-diameter bottom surface.