JPS61279456A - Blade for machining ceramics in center-less grinder - Google Patents

Abstract

PURPOSE:To lessen the wear of a blade face where a workpiece passes, by applying nitrided silicone sinter to the blade edge of a center-less grinder. CONSTITUTION:In a center-less grinder, an adjusting grinding wheel 8 is so arranged as to have its axial line slightly aslant toward a grinding wheel 7, and consequently a workpiece 9 of round bar shape moves on the slant face 5b of a blade 5 for being machined to a round bar of predetermined outer diameter, when one end of the workpiece 9 is fed to said slant face 5b. The blade 5 connected to the slant top of a metal support 5a has an edge 5b of nitrided silicone sinter processed by a hot press. Also, the foot of the blade 5 is fixed by a metal holder 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a ceramic grinding blade for a centerless grinder that prevents crater-like wear on a surface through which a workpiece passes.

[Technical background of the invention and its problems] Conventionally, as shown in FIG. 3, a cylindrical grinding wheel 1 and a cylindrical adjusting wheel 2 have been arranged in parallel with their rotation axes C1 and C2 slightly inclined. , a centerless grinder is known in which a blade 3 made of carbide or W4 is arranged parallel to the grinding wheel 1, and the blade 3 is made of carbide or W4 and has an inclined surface 3a slightly inclined toward the adjusting wheel 2 at the top thereof. .

This centerless grinder has an inclined surface 3 of a blade 3.
When a round bar-shaped workpiece 4 is inserted from one end onto the blade 3, the workpiece 4 is placed on the inclined surface 3a of the blade 3, since the adjusting grindstone 2 is arranged with its axis slightly inclined with respect to the grinding wheel 1. Proceed upward as shown by the arrow in Fig. 4 until the workpiece 4
is ground into a round bar with a specified outer diameter.

However, when the blade 3 in such a conventional centerless grinder grinds a ceramic workpiece, as shown in FIG. There was a problem with this.

[Purpose of the Invention] The present inventors conducted intensive research to solve these conventional difficulties, and found that the degree of wear of materials that rub against each other is affected by the affinity of the two, and that ceramic sintering We found that when two materials with high affinity, such as a body and a metal, are rubbed together, the wear on the soft material side, that is, the metal side, is significantly greater.Also, when two ceramics are rubbed together, the same material It was also found that the amount of wear caused by ceramics of different types was greater than that between ceramics of different types.

The present invention has been made based on such knowledge, and an object of the present invention is to provide a ceramic grinding blade for a centerless grinder that reduces wear on the surface through which the grinder passes.

[Summary of the Invention] The present invention provides a blade for forming a passage for a workpiece installed between a grinding wheel and an adjusting wheel in a centerless grinder, by forming at least the top portion of the blade with a silicon nitride sintered body. This reduces wear on the workpiece passing surface of the blade.

[Embodiments of the invention] Examples of the present invention will be described below.

FIG. 1 is a sectional view of an embodiment of the present invention.

In the blade 5 of this embodiment, the top part of the metal support part 5a is inclined, a chip 5b made of a silicon nitride (Si3N+) sintered body manufactured by hot pressing is bonded thereto, and the base part is attached to a metal gripping member. 6.

7 is a grinding wheel, 8 is an adjustment wheel, and 9 is a workpiece.

Further, the blade 10 shown in FIG. 2 is formed entirely of a hot-pressed silicon nitride sintered body, and its base is gripped by a metal gripping member 11.

Using a blade configured in this way, a diameter of 13 mmφ
, length 140mm, width 9.5mm silicon nitride (3i3N)
+) When a round bar made of a sintered body was ground by the through-feed method, the flatness of the 200th round bar was 2 μm in the length direction, 1 μm in the width direction, and its rigidity was 1 μm.
m/kg.

On the other hand, when grinding a workpiece of the same size and quality under the same conditions using a conventional tool (one in which a carbide tip is brazed to the top of the metal support), the 200th 0 round bar The flatness is 0.8m in the length direction and 0.8m in the width direction.
9 m, and its stiffness was 3 μTrL/8. In addition, a crater-shaped depression with a depth of 0.9 m was formed in the center of the workpiece passing surface due to wear.

[Brief explanation of the drawing]

Fig. 1 is a front view showing one embodiment of the present invention, Fig. 2 is a front view showing another embodiment of the invention, Fig. 3 is a side view showing the configuration of centerless grinding, and Fig. 4 is a front view showing an embodiment of the present invention. FIG. 5 is a perspective view showing the feeding direction of the workpiece on the blade, and FIG. 5 is a perspective view showing wear on the crater formed on the inclined surface of the conventional blade. 5...Blade 5a...Metal support portion 5b...Chip made of silicon nitride sintered body 6.11...・Metal support member 7...Search grindstone 8...Adjustment grindstone 10...Silicon nitride Sintered body blade Applicant Toshiba Corporation Patent attorney Sa Suyama - Figure 1 Figure 2 Figure 3 Figure 4, & Figure 45

Claims (2)

[Claims] (1) In a centerless grinder characterized in that at least the top of the blade for forming a passage for the workpiece installed between the grinding wheel and the adjusting wheel in the centerless grinder is formed of a silicon nitride sintered body. Blade for ceramic grinding. (2) A ceramic grinding blade in a centerless grinder according to claim 1, wherein the silicon nitride sintered body is manufactured by hot press sintering.