JPS61159377A - Grinding device - Google Patents

Abstract

PURPOSE:To prevent the temperature rise of a whetstone foundation metal and ensure steady high precision processing by forming fluid passages from the internal space of a main spindle to that of a whetstone. CONSTITUTION:A whetstone 7 rotates monolithically with a main spindle 1 and processes a workpiece (a) with its peripheral whetstone layer 10. At this time, a cooling fluid common to a grinding fluid is forcibly supplied in turn from and introducing inlet 18 to the through-hole 16 of the said main spindle 1. The cooling fluid overflows from the surface of the whetstone layer 10, pass ing through each branch passage 19, a concave groove 17, each guide passage 20 and each through-hole 15 of the whetstone 7 in order, starting from the said through-hole 16. The constant flow of the cooling fluid from the main spindle 1 to the whetstone 7 absorbs heat, if generated at the slidable connection between the main spindle 1 and an oil seal 4, thereby preventing the temperature rise of a whetstone foundation metal 9, controlling the thermal expansion of the said foundation metal 9 and stabilizing the precision of processing the work piece (a).

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a grinding device for grinding ceramic sintered bodies and the like.

[Technical background of the invention and its problems]

This type of grinding device attaches a cylindrical grindstone (such as a diamond grindstone) to a main shaft that is linked to a motor, and rotates this grindstone together with the main shaft. It grinds the workpiece.

The main shaft is rotatably supported via a bearing, and lubricating oil is sequentially supplied and circulated between the bearing and the main shaft. The main shaft passes through the side wall of the bearing case, and the penetrating portion is sealed by an oil seal, and this seal prevents lubricating oil from leaking.

However, when the main shaft rotates at high speed, a large amount of heat is generated due to friction at the sliding contact area between the main shaft and the oil seal, and this heat is transmitted to the grindstone through the main shaft. A whetstone consists of a whetstone layer made of diamond particles on the outer circumferential surface of a whetstone base metal made of metal such as aluminum. When heat is transferred to this whetstone, the whetstone base metal expands thermally, causing the external dimensions of the whetstone to change. Discrepancies occur, and as a result, the accuracy of grinding the workpiece decreases, making it difficult to perform highly precise machining.

[Purpose of the invention]

This invention was made with attention to these points, and its purpose is to prevent the temperature rise of the grinding wheel base metal and to constantly perform highly precise grinding. The goal is to provide equipment.

[Summary of the invention]

That is, in this invention, a through hole is formed extending from the inside of the spindle to the inside of the grinding wheel, a cooling liquid is made to flow through this through hole, and this cooling liquid prevents the temperature of the grinding wheel base metal from rising.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 1 is the main shaft of a centerless grinding device. One end of the main shaft 1 is rotatably supported by a bearing 2, and in this supported state, it rotates at high speed in conjunction with a motor (not shown) as a drive source. be.

The bearing 2 is covered with a bearing case 3, and this bearing case 3 is further covered with an outer case 3a. And an oil hole 2 formed across the outer case 3a, the bearing case 3, and the bearing 2.
Lubricating oil is sequentially supplied to the bearing surface of the bearing 2 through the shaft a and is circulated. The main shaft 1 passes through a side wall of a bearing case 3, and the penetrating portion is sealed by an oil seal 4.

The tip of the main shaft 1 protruding from the bearing case 3 is formed into a tapered shape, a flange 6 is attached to the tapered portion 5, and a grindstone 7 is attached to the outer periphery of the flange 6. 7 The flange 6 has an inner circumferential surface formed in a tapered shape corresponding to the tapered portion 5, and is tightly joined to the tapered portion 5, and is attached to the main shaft 1 by a nut 8 screwed onto the tip of the main shaft 1. It is firmly fixed against the The whetstone 7 is formed by applying a grindstone 1f110 made of diamond particles to the outer peripheral surface of a cylindrical whetstone base metal 9 made of aluminum, and the whetstone base metal 9 is fitted onto the outer circumference of the flange 6. An engaging protrusion 11 is integrally formed on the outer peripheral edge of one end of the flange 6, and one end surface of the grindstone base metal 9 is in contact with this engaging protrusion 11. Further, on the other end side of the flange 6, a ring-shaped presser 12 is provided.
is attached, and this holding tool 12 is fixed to the flange 6 via bolts 13 so as to come into contact with the other end surface of the 7 flange 6, whereby the grinding wheel base metal 9 is connected to the engagement protrusion 11 and the holding tool 12. is sandwiched between.

The grinding wheel 7 is divided into a plurality of parts in the axial direction, for example, as shown in the figure, into horizontal divided pieces 7a..., and grooves 14 are formed radially on the end surfaces of the pieces that come into contact with each other.
Through these grooves 14, through holes 15, which penetrate from the inner peripheral surface of the whetstone base metal 9 to the surface of the whetstone layer 10, are formed between the divided pieces 7a.

Each divided piece 7a... is a long bolt 2)...
and nuts 2)a... are integrally connected. A through hole 16 is formed in the center of the tip of the main shaft 1 along its axial direction, and a groove 17 is formed in the inner peripheral surface of the seven flange 6 along its circumferential direction. One end of the through hole 16 is open to the end face of the tip of the main shaft 1 as an introduction port 18, and the other end communicates with a groove 17 via a radial branch path 19. The passages 2o communicate with the through holes 15 of the grindstone 7, respectively.

Next, we will discuss the effect.

The whetstone 7 rotates together with the main shaft 1, and the whetstone layer 10 on its outer periphery
Grind the workpiece a. At this time, a cooling liquid which also serves as a grinding liquid is sequentially pumped from the inlet 18 to the through hole 16 of the main shaft 1.

This coolant flows from the through hole 16 to each branch path 19..., to the concave groove 1.
7, it flows out from the surface of the grindstone layer 10 through each guide path 20... and each through hole 15... In this way, the coolant constantly flows from the main spindle 1 to the grinding wheel 7, so even if heat is generated at the sliding contact area between the main spindle 1 and the oil seal 4, it is absorbed by the coolant, and therefore the heat is absorbed by the coolant. is not transmitted to the grinding wheel base metal 9, which means that the temperature rise of the grinding wheel base metal 9 can be prevented, thereby suppressing the thermal expansion of the grinding wheel base metal 9, and stabilizing the machining accuracy for the workpiece a. A high degree of precision machining can be achieved. The above-mentioned cooling liquid also serves as a grinding liquid, but a part of it diffuses into the grinding surface of the workpiece a, so that the grinding operation can be smoothly performed using the cooling liquid without using a separate grinding liquid. , frictional heat can be suppressed.

In addition, in the above embodiment, the through hole 15 of the grindstone base metal 9 is
... were opened to the surface of the whetstone layer 10, but as shown in FIG. It may be made to open to the side, and in such a case, the through hole 15a...
- Since the length is extended inside the grinding wheel base metal 9, it is advantageous in that the grinding wheel base metal 9 can be cooled even more efficiently. However, in this case, since the cooling liquid flows out to the end face side of the grinding wheel base metal 9, the grinding liquid is radiated onto the grinding surface of the workpiece a by a separate means.

〔Effect of the invention〕

As explained above, according to the present invention, a through hole is formed from the inside of the spindle to the inside of the grinding wheel, and the coolant is allowed to flow through this hole, thereby preventing the temperature rise of the grinding wheel base metal. However, the present invention has the effect of stabilizing the machining accuracy of the workpiece and constantly achieving high precision machining.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the invention, FIG. 2 is a perspective view showing divided pieces of a grindstone in the same embodiment, and FIG. 3 is a sectional view showing another embodiment of the invention. 1...Main shaft, 7...Whetstone, 9...Whetstone base metal, 10
...Whetstone layer, 15.16...Through hole. Applicant's agent Patent attorney Takehiko Suzue Figure 1a Figure 2

Claims (5)

[Claims] (1) A grindstone made of a grindstone layer on the outer circumferential surface of a grindstone base metal is attached to the main shaft that rotates in conjunction with the drive source, and this grindstone is rotated together with the main shaft, and the workpiece is processed using the grindstone layer on the outer periphery. What is claimed is: 1. A grinding device for grinding, characterized in that a through hole is formed extending from the inside of the main spindle to the inside of the grindstone, and a cooling liquid is allowed to flow through the through hole. (2) The grinding device according to claim 1, wherein the through hole is open to the surface of the grinding wheel layer, and a cooling liquid which also serves as a grinding liquid flows through the through hole. (3) The grinding device according to claim 1, wherein the through hole is open to an end face of the grindstone base metal. (4) Grinding according to claim 1, 2, or 3, characterized in that the grindstone is divided into a plurality of parts in the axial direction, and through holes are formed in the divided surfaces. Device. (5) The grinding device according to claim 1, 2, 3, or 4, wherein the grindstone layer is made of diamond particles.