JPH01310863A - Static pressure pneumatic bearing structure of rotary grinder cutter - Google Patents

Abstract

PURPOSE:To suppress the instruction of the grinding liquid and grinding mists into a bearing part and keeping the bearing part in the favourable state by holding a spindle having a rotary grinder cutter installed at the top edge, in rotatable manners by a bearing part consisting of a static pressure radial pneumatic bearing and a static pressure thrust bearing and supplying the compressed air into the bearing part. CONSTITUTION:An edge plate 17 is installed on the outer periphery of a spindle 12 set between a rotary grinder cutter 11 and a static pressure radial pneumatic bearing 14, and an air feeding pocket 21 and an air discharge pocket 21b which communicate to a gap between the outer peripheral surface of the spindle and the inner peripheral surface of the edge plate are formed on the edge plate 17. The compressed air for the charge of the air feeding pocket 21a is blown into the static pressure radial pneumatic bearing 14 and a static pressure thrust pneumatic bearing 20 through a small penetration hole 22 and the gap, and the grinding liquid and grinding mists are discharged outside. Further, the residual portion of the grinding liquid which intrudes into the bearing part is discharged outside through the air discharge pocket 21b. Therefore, the bearing part for the spindle 12 having the rotary grinder cutter 11 installed at the top edge is maintained in the favorable state.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a machine equipped with two grinding processes for grooving and cutting of hard and brittle abrasive materials such as ferrite, which is a constituent material of magnetic heads. The present invention relates to a hydrostatic air bearing structure for a rotating grindstone blade.

[Conventional technology]

Conventionally, as shown in Fig. 2, the bearing structure of this type of rotary whetstone blade has conventionally been such that a spindle (2) with a rotary whetstone blade (1) attached to its tip is rotatably mounted on a hydrostatic radial air bearing (3). The rotating whetstone blade (1) is supported by
is formed into a ring plate shape, and a set of two fixed support rings (
4) It is clamped between the flange parts provided on the outer periphery of (5) and is tightened and fixed by a nut (6) screwed onto one fixed support ring (4), and the spindle (2
) is attached to the distal end of the wheel mount (7) by inserting the fixed support ring (4) thereinto and fastening it with a nut (8).

Further, the static pressure radial air bearing (3) is attached to the spindle (
2) and the journal housing (9) that matches this one.
The static pressure air supplied to the annular gap (SO) between the
2. Place the spindle (2) in the journal housing (9).
It is rotatably supported in a state of ￥10. (
10) is an end plate attached to the front end surface of the internal housing (9).

[Problem to be solved by the invention]

However, in the conventional structure as described above, during the grinding process, the grinding liquid supplied to the rotary whetstone blade (1) and the grinding mist generated during the grinding process are transferred to the end plate (10) and the spindle (2). The air enters the hydrostatic radial air bearing (3) through the gap (sl) between the spindle (2) and journal housing (9) that constitute the bearing (3).
There was a risk of burning.

The present invention has been made to solve these conventional problems, and its purpose is to reliably prevent grinding fluid and grinding mist from entering the bearing structure.

[Means for Solving the Problems] - In order to achieve the objective -1, the present invention provides a bearing in which a spindle equipped with a rotating grindstone blade at the tip is composed of a hydrostatic radial air bearing and a hydrostatic thrust air bearing. It is characterized in that it is rotatably held in the bearing part and compressed air is supplied to the bearing part.

Furthermore, the structure for supplying compressed air to the bearing section is as follows:
An end plate is attached to the outer periphery of the spindle between the rotary grindstone blade and the hydrostatic radial air bearing, and the end plate is provided with an air supply pocket and an exhaust pocket that communicate with the gap between the outer circumferential surface of the spindle and the inner circumferential surface of the end plate. In addition, it is preferable that the air supply pocket is provided with a through hole that communicates with the outside, and the compressed air is allowed to flow out through the through hole and the gap.

[For production]

According to the present invention, the grinding side 1-n! The grinding fluid supplied to the rotary grinding wheel blade and the grinding mist emitted during heating are blown away by the compressed air and prevented from entering the bearing, so the bearing is always free from contaminants. It will be maintained in good condition without any intervention.

In addition, the iE compressed air filled in the air supply pocket is blown onto the 1F radial air bearing and the hydrostatic thrust air bearing through the small through holes and gaps, and the air is discharged to the outside together with the grinding fluid and grinding mist.

Further, the remainder of the grinding fluid that has entered the bearing portion is discharged to the outside through the exhaust pocket.

Furthermore, according to the configuration described in ``-'', the compressed air supply passage can be formed using the end plate.

〔Example〕

Embodiments of the present invention will now be described in detail with reference to the drawings. In FIG. 1, (11) is a rotating grindstone blade, (12) is a spindle on which the rotating grindstone blade (II) is attached, (13)
1 is a journal housing into which a spindle (12) is rotatably fitted, and static pressure air supplied to an annular gap between the spindle (12) and the journal housing (13) causes air to flow inside the journal housing (13). A hydrostatic radial air bearing (14) is configured to rotatably support the spindle (12) in a floating state.

The rotary grindstone blade (11) is formed in the shape of an extremely thin ring plate, and is fixed to the spindle (12) in a state where it is fixedly held between two fixed support rings (15a) and (15b). That is, the fixed support ring (+5a) (+5b
) have a flange part on the outer periphery, and one fixed support ring (!5a) has a rotating whetstone blade (11) on the outer periphery.
, and the other fixed support ring (15b), and by screwing the nib (+6) into the threaded part formed on the outer peripheral end of one of the fixed support rings (15a), the rotary whetstone blade ( 11) is fixedly held between the flange portions of both fixed support rings (15a) (+5b).

-, the spindle (12) is connected to the main shaft part (12).
At the tip of a), there is an end plate fitting part (
+2b), the grinding wheel blade attachment taper part (12c) and the tip threaded part (12d) are formed in a stepped shape, and the main shaft part (+2a) is an annular gap where static pressure air is supplied as described above. (go) through the journal housing (
13), and the end plate (17) is rotatably fitted to the end plate fitting portion (+2b) in a state in which the end plate (17) is in full contact with the journal housing (13).

Furthermore, one fixed support ring (15a) that holds the rotary grindstone blade (11) is fitted into the grindstone blade attachment taper part (12c) via a wheel mount (+8), and this fixed support ring ( +5a) is screwed onto the threaded part (+2d') by the Nand (19), which presses the fixed support ring (15a) onto the flange part (18a) provided on the wheel mount (18), and then attaches the fixed support ring (15a) to the grinding wheel blade mounting taper part (12c). ),
This allows the rotary grindstone blade (If) to be attached to the spindle (I2
) is fixed.

The end plate (+7) is connected to the end plate fitting portion (+7) of the spindle (12).
A fitting hole portion (17a) that fits into the spindle (12b), and a grinding wheel blade attachment taper portion (12c) of the spindle (12) that has a larger diameter than this.
) and a ring-shaped recess into which the flange (+8a) of the wheel mount (+8) projects into the open end of the sleeve fitting hole (+7b). (+7c), and this concave part (17c) and the wheel mount (18) create a static gap between the concave part (17c) and the end face of the flange part (18a) of the wheel mount (1st). Gap where compressed air exists (g+
) A hydrostatic thrust air bearing (20) is configured.

The end plate (17) also has the fitting hole (17a).
When opened, an air supply pocket (2+a) and an exhaust pocket (21b) are formed which communicate with the gap (g2) between the inner peripheral surface of the end plate and the end plate fitting portion (+2b) of the spindle (I2). has been done. Among these, there are a plurality of small through holes (22) between the air supply hole (21a) and the recessed part (+7c).
)(22)...(22) are drilled. Furthermore, the end plate (17) is formed with passage holes (23) and (24) extending from the air supply pocket (21a) and the exhaust pocket (21b), and these passage holes (23H24) are formed in the journal housing (13). ) formed in the passage hole (23
a) (24a), and is connected to the air supply side passage hole (24a).
23) is connected to a compressed air supply source via the passage hole (23a), and the exhaust side passage hole (24) is connected to the passage hole (24a).
) to the outside.

In the configuration described above, compressed air is filled from the supply source into the air supply pocket (21a) through the passage hole (23aH23), and is passed through the air supply pocket (21a) to the large 21
' is supplied to the static pressure thrust air bearing (20), and the remaining part branches out from the air supply pocket (21a) 1) No. 11 and flows through the small through holes (22) (22)... (22) into the gap ( By releasing this compressed air, the grinding fluid supplied to the rotary grinding wheel blade (11) and the grinding mist generated during grinding are transferred to the static pressure radial air bearing (
14) and the hydrostatic thrust air bearing (20).

Furthermore, the grinding fluid and grinding mist that have passed through the static pressure thrust air bearing (20) and entered the rear side from the opening of the air supply pocket (21a) are removed from the exhaust pocket (21b) through the passage hole (24).
It is discharged to the outside through H24a). Therefore, during the grinding process, it is possible to reliably prevent the grinding fluid and grinding mist from entering the bearing part, and the static pressure radial air bearing (I4
) can reliably prevent seizure of the spindle (I2) and journal housing (13).

〔Effect of the invention〕

As explained above, when the rotary abrasive blade of the present invention has a hydrostatic air bearing structure, the spindle with the rotary abrasive blade attached to the tip has a bearing portion consisting of a hydrostatic radial air bearing and a hydrostatic thrust air bearing. The grinding fluid supplied to the rotary grindstone blade during grinding and the grinding mist generated during grinding are supplied to the bearing. Since the compressed air is blown away and prevented from entering the bearing, the bearing can always be kept in good condition free of foreign matter, and the risk of seizure can be reliably prevented. Ta.

In addition, as a structure for supplying compressed air to the gap, an end plate is attached to the outer periphery of the spindle between the rotating grindstone blade and the static pressure radial air bearing, and this end plate is attached to the gap between the outer circumferential surface of the spindle and the inner circumferential surface of the end plate. In addition to providing an air supply pocket that communicates with the bearing, a small through hole that communicates with the outside is provided in the air supply pocket, and the compressed air flows outside through this small through hole and the gap, so generally the front surface of the bearing A compressed air supply passage can be formed using the end plate attached to the
In addition, the end plate has a simple structure in which a small through hole, which is a part of the supply passage, is provided in the cylinder to communicate with the gap, and there is no need to separately provide a compressed air supply structure. However, it achieved excellent results.

40 illustrations! 11. Explanation: Fig. 1 does not show an embodiment of the present invention; (2) A cross-sectional view; Fig. 2 is a cross-sectional view of a main part of a conventional example.

(11)...Rotating grindstone blade, (+2)...Spindle, (I4)...Static pressure radial air bearing, (17)...
・End plate, (20)...static thrust air bearing, (2+
a)...Air supply pocket, (21b)...Exhaust pocket, (22)...Through small hole, (g2)...Gap.

=11- CSCN

Claims (2)

[Claims] (1) A spindle with a rotary grindstone blade attached to its tip is rotatably held in a bearing section consisting of a hydrostatic radial air bearing and a static thrust air bearing, and compressed air is supplied to the bearing section. The static pressure air bearing structure of the rotating whetstone blade is characterized by: (2) An end plate is attached to the outer periphery of the spindle between the rotary grindstone blade and the hydrostatic radial air bearing, and this end plate has an air supply pocket and an exhaust pocket that communicate with the gap between the outer circumferential surface of the spindle and the inner circumferential surface of the end plate. The static pressure of the rotary grindstone blade according to claim 1, wherein the air supply pocket is provided with a small through hole that communicates with the outside, and the compressed air is allowed to flow out through the small through hole and the gap. Air bearing structure.