JPS61284370A - High-speed grinding method for internal surface of ceramics - Google Patents

Abstract

PURPOSE:To make finish processing of the internal surface of a work quickly and accurately by flushing high-pressure cooling water to a diamond grinder for removal of dust as product of grinding and for cooling, thereby preventing the cutting edge of diamond grinder from heat damage and defoliation and meantime CNC controlling the grinder depth feed table and machining spindle table. CONSTITUTION:An object to be processed 1 and a diamond grinder 3 are rotated at a high speed in opposite directions to each other, and high-pressure cooling water is flushed to the diamond grinder 3 from a coolant jetting tube 5. Thereby the grinder 3 is prevented from dullification and also from heat damage and defoliation of the cutting edge with its cooling action, and a plunge cuts in radial direction are repeated superposed until the depth feed attains a specified dimension. Then traverse cuts are made 2-3 times as finish processing. This provides high-speed grinding of the internal surface of a ceramic work stably and precisely.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for high-speed grinding of the inner surface of ceramics for finishing the inner diameter of a ceramic workpiece at high speed and precision.

(Prior art and technical issues) Conventionally, high hardness and high density ceramic materials such as silicon nitride, 5N4S zirconia ZRO□, Mesis carbide, and alumina Al2O3 have been grinded using the same method as the conventional metal grinding method. If this were to be done, it would take an extremely long time, and it would be almost impossible to grind, making it impractical. In particular, when grinding the inner surface of the ceramic workpiece mentioned above, the arc of contact between the grinding wheel and the workpiece is long, and the grinding wheel shaft lacks rigidity, so many attempts have been made using diamond grinding wheels and various independent processing methods. However, the current trend in this field is that no sufficient effect can be obtained, and high-speed grinding of the inner surface of ceramics is considered almost impossible.

Therefore, the technical object of the present invention is to provide a processing method that can grind and finish the inner surface of a workpiece made of Hashi ceramic materials at high speed and precision, which has been thought to be impossible in the past.

(Technical means) The high-speed internal grinding method for ceramics of the present invention involves injecting high-pressure cooling water onto a diamond grinding wheel to remove grinding powder that causes clogging of the grinding wheel and cooling it at the same time. This prevents burnout and peeling of the diamond cutting edge due to high heat, and controls the grindstone cutting head and work headstock using CNO control, and superimposes the plunge curve to quickly cut the inner surface of the workpiece hole of various ceramic materials to the specified size. It is characterized by making a notch, then adding a traverse cut to finish.

Next, this invention will be explained with reference to the drawings.

First, / is a workpiece having a hole inner surface 2, which is chucked to the main spindle of a work headstock. 3 is a diamond grindstone attached to a grindstone spindle, and 3 is a cooling water injection pipe. In addition, since the grinding wheel spindle Hiroshi requires high rigidity,
The grindstone tiles are made of tungsten alloy heavy metal, and an oil-air type is used to increase the diameter of the spindle. Further, a diamond grinding wheel 3 made by electrodeposition is used as a grinding wheel, and the diamond grinding wheel 3 is used without grinding.

That is, the workpiece/and the diamond grinding wheel 3 are rotated at high speed in opposite directions, and high-pressure cooling water is injected to the diamond grinding wheel 3 from the cooling water injection pipe j, and the diamond grinding wheel 3 is cut and cooled. 3.5 mm per minute while preventing burnout and peeling of the cutting edge. ! ; Plunge cuts were superimposed in the radial direction at a cutting speed of mm and repeated 9 times;
After cutting to the specified dimensions, make 2 traverse cuts.
Finishing is completed by repeating ~3 times.

In particular, high-speed internal grinding of ceramic materials cannot be expected without plunge grinding.

Furthermore, since there is no suitable method for economically dressing a diamond grinding wheel, high-pressure (75 to 9/e11) cooling water is injected onto the diamond grinding wheel during grinding to prevent clogging of the grinding wheel. High speed (peripheral speed/roo~ro
This prevents abrasive grains from being burnt out, peeled off, or fallen off due to the high heat generated during heavy grinding.

(Effect of the invention) Next, the effects of this invention will be described with reference to Examples.

Example ceramic material (silicon nitride, Vickers hardness/60
0 to 9/rr M)゛ hole diameter sofP1mIx grinding length 10O#n, and diamond lower grinding wheel diameter≠j;m
ml x width 2Qmm, after 6 plunge cuts,
Traverse cut 2 to 3 times and grind to a radius of 7mm
In this case, the processing time was 3 minutes and 10 seconds, which was about 7 seconds using the conventional processing method.
It was 750 hours.

As described above, the present invention uses a diamond grinding wheel made by non-dressing electrodeposition on a highly rigid grinding wheel spindle, injects high pressure cooling water to the diamond grinding wheel during grinding operation, and performs plunge superposition grinding. By adopting a combined grinding method of grinding and traverse grinding, it has become possible to stably and accurately grind the internal surface of ceramic materials at high speed, which was previously considered almost impossible.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an explanatory diagram of the processing state, and FIG. 2 is a diagram of the stroke of the grindstone. /0. Processed product, 26. Inner surface of hole, 30. Diamond whetstone, 10. Grinding wheel spindle, 50. Cooling water injection pipe patent applicant Taisei Kikai Co., Ltd. 6115 people: 0 Koichi No. 11 Liquor 1174 Mi Figure 1 Figure 2 Figure 21. Hole inner surface 31. Diamond whetstone ≠ 0. Grindstone spindle 2. cooling water injection pipe

Claims (1)

[Claims] High-pressure cooling water is injected onto the diamond grinding wheel to remove grinding powder that causes clogging of the grinding wheel, while also preventing burnout and peeling of the diamond cutting edge due to high heat. control the stand,
A high-speed grinding method for the internal surface of ceramics, which is characterized by superimposing plunge cuts to cut the inner surface of the workpiece hole of various ceramic materials to a predetermined dimension at high speed, and then finishing by adding a traverse cut.