JP2659235B2 - Planar polishing apparatus and method for producing polished product with uniform polishing marks - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar polishing apparatus used for polishing an aluminum substrate for a magnetic disk and other objects to be polished, and a method for manufacturing a polished product having a uniform direction of polishing marks.

2. Description of the Related Art As one type of a planar polishing apparatus of this kind, a pair of grindstones rotatably provided, and an object holder to be polished provided revolvably while rotating between these grindstones, are provided. 2. Description of the Related Art There is known a planar polishing apparatus which performs a polishing process on an object to be polished by rotating the grindstone pressed against the object to be polished while rotating and revolving a retainer. According to such a polishing apparatus, the object-to-be-polished retainer itself rotates and revolves, so that the object to be polished can be evenly polished on the entire polished surface of the grindstone, and it is possible to prevent the loss of the grindstone and to improve the processing accuracy. A polished surface can be obtained.

Problems to be Solved by the Invention However, in the above-mentioned planar polishing apparatus, conventionally, the rotation stop of the grindstone and the rotation stop of the holder for the object to be polished are always performed at the same time.

In other words, the polishing direction of the object to be polished is constantly changing during processing due to the rotation and revolution of the holder for the object to be polished, but the grindstone also stops at the same time as the rotation of the holder is stopped. In many cases, the directions of the polishing marks on the polished material are not uniform. For this reason, there is a drawback that it is difficult to manufacture a material such as an Al substrate for a magnetic disk, which requires polishing marks to be aligned in a certain direction as a product quality, with good retention using this polishing apparatus.

The present invention has been made in view of such a technical background, and an object of the present invention is to provide a planar polishing apparatus capable of uniformly aligning the direction of a polishing mark. It is intended to provide a manufacturing method.

Means for Solving the Problems For the above purpose, the present invention, referring to the reference numerals in the drawings, shows a pair of rotatably provided grinding wheels (3).
And (4) a holder for the object to be polished (7) provided so as to be able to revolve while rotating between these whetstones. The holder is pressed against the object to be polished (B) while rotating and revolving the holder. In a planar polishing apparatus configured to perform polishing of an object to be polished by rotating the grindstones (3) and (4), a predetermined time lag is provided after a rotation stop rotation of the object to be polished holder (7). A mechanism for stopping the rotation of the grindstones (3) and (4) is provided. Furthermore, between the pair of rotatably provided grinding wheels (3) and (4), the workpiece holder (7) is revolved while rotating, and is pressed against the workpiece (B). Whetstone (3)
In the method for manufacturing a polished product in which the object (B) is polished by rotating (4), the rotation of the holder (7) is first stopped, and then the grinding wheel is placed at a predetermined time lag. (3) The rotation of (4) is stopped.

Here, the grindstones (3) and (4) are generally attached to the inner surfaces of a pair of rotation facing plates (1) and (2) as shown in FIGS. It is rotatably supported. The most common configuration for enabling the holder (7) to be polished to rotate and revolve is a sun gear in which the holder (7) is arranged at the center of rotation of the grindstones (3) and (4). Both (5) and the internal gear (6) arranged concentrically outside the sun gear (5) have their outer peripheral surfaces meshed with each other, and these sun gear (5) and the internal gear ( And 6) may be rotated. Further, the rotation of the grindstones, that is, the platens (1) and (2), the planetary gears (5) and the internal gear (6) is performed by motors (11) to (13), and the motors are driven by a timer (21). It is generally performed by (22). Accordingly, the mechanism for stopping the rotation of the grindstones (3) and (4) with a predetermined time lag after the stop of the rotation / revolution of the workpiece holder (7) is a timer (2).
1) It is good to incorporate into (22).

After setting the work to be polished (B) in the holder (7), the platens (1) and (2) are brought close to each other, and the grindstone (3) is pressed at a predetermined pressure.
(4) is pressed against the object to be polished (B). Next, the first and second motors for controlling the operations of the first to third motors (11) to (13) for rotating and driving the sun gear (5), the internal gear (6), and the platens (1) and (2). Timers (21) and (22) are turned on at the same time. As a result, as shown in FIG. 3, the speed of the sun gear (5), the internal gear (6), and the surface plates (1) and (2) gradually increases after starting rotation. Due to the rotation of the sun gear (5) and the internal gear (6), the workpiece holder (7) starts revolving with respect to the rotation center of the grinding wheel. After speed increase, sun gear (5), internal gear (6), surface plate (1)
(2) is a constant-speed rotation (N ₁ ) (N ₂ ) (N ₃ ) ( ₄ ), and the grinding of the workpiece (B) is performed by the action of the grindstones (3) and (4). After a lapse of a predetermined time (T ₂ ), first, the second timer (22) is turned off. As a result, the second and third motors (12) and (13) are turned off, but the sun gear (5) and the internal gear (6) gradually decelerate while rotating by inertial force and then stop. First timer (21) is turned OFF at a time lag after OFF of the second timer (22) (T ₁ -T _2). This turns off the first motor (11), but the platens (1) and (2)
Is rotating by inertial force while gradually decelerating. During this time, the object (B) to be polished of the holder (7) that has already stopped is polished. Thus, just before the end of the polishing process,
Since there is a period in which only the grindstones (3) and (4) are rotated and the processing is performed in a state where the retainer (7) is stopped, the polishing direction of the object to be polished (B) becomes a fixed direction, and the resulting polished product Will also be aligned in a certain direction.

Embodiment Next, the configuration of the present invention will be described based on the embodiment shown in FIGS.

In FIGS. 1 and 2, (A) is a flat surface polishing apparatus, which comprises a pair of upper and lower opposing platens (1) and (2), and upper and lower grinding wheels (3) attached to the inner surface of each platen. ), (4), a sun gear (5) arranged at the axis of the grindstone between the grinding wheels (3) and (4), and an internal gear (5) arranged concentrically outside the sun gear (5). 6) and one or two or more thin plate spur-shaped workpiece holders (7) arranged so that the outer peripheral surface is meshed with any of the sun gear (5) and the internal gear (6). And Also, a plurality of holes are formed in each of the retainers (7), and a disk-shaped object to be polished (B) thicker than the retainers is held in these holes. . Further, the upper and lower stools (1) and (2) are connected to a first motor (11) via drive shafts (1a) (2a) and sprockets (1b) (2b), and are rotated by the drive of the motor (11). Is to be done. The platen (1) is supported by a cylinder (not shown) so as to be able to move up and down, and engages with an engaging portion (1a ') at the upper end of the drive shaft (1a) at a lowered position shown in FIG. , A rotational force in a direction opposite to that of the lower platen (2) is applied. On the other hand, the sun gear (5) is connected to the second motor (12) via the drive shaft (5a) and the sprocket (5b), and the internal gear (6) is connected via the drive shaft (6a) and the sprocket (6b). The third motor (13) is connected to the third motor (13), and the motors (12) and (13) are driven to rotate at different rotational speeds, whereby the retainer (7) can revolve while rotating in a planetary gear shape. It has been done. Also, the operation of the first motor (11) is controlled by a first timer (21), OF When the first timer has elapsed time T ₁ after ON
F is set to. On the other hand, the operation of each of the second and third motors (12) and (13) is controlled by a second timer (22), and the second timer (22) is turned off when T ₂ hours elapse after being turned on. ing. And Thus, the operation time T ₁ of the first timer (21) is set to be longer than the operating time T ₂ of the second timer (22). As a result, after the rotation of the sun gear (5) and the internal gear (6) is stopped, a time lag of approximately (T ₁ -T ₂ ) is left, and the upper and lower platens (1)
The rotation of (2) is stopped. here,
A preferable value of (T ₁ −T ₂ ) is preferably set to about 1 to 10 seconds. The rotation speeds of the platens (1) and (2), the sun gear (5), and the internal gear (6) are set to predetermined ratios so that both surfaces of the workpiece (B) can be processed equally. Have been.

Next, the operation of the illustrated planar polishing apparatus will be described with reference to the operation characteristic diagram of FIG.

First, after the object to be polished (B) is set in the object to be polished holder (7), the upper and lower platens (1) and (2) are connected and approached to apply the grindstones (3) and (4) at a predetermined pressure. It is brought into pressure contact with the polishing object (B). Then, the first timer (21) and the second timer (2
2) turns ON at the same time. Then the first to third motors (1
1) (12) and (13) are driven, whereby the upper and lower stools (1) and (2), the sun gear (5), and the internal gear (6) start rotating and then rotate as shown in FIG. Gradually rises. On the other hand, by the rotation of the sun gear (5) and the internal gear (6), the workpiece holder (7) starts revolving around the rotation center of the upper and lower grinding wheels (3) and (4). After speed increase, sun gear (5), internal gear (6), surface plate (1)
(2) becomes constant speed rotation (N ₁ ) (N ₂ ) (N ₃ ) (N ₄ ). First, second first second timer when after ON of the timer time T ₂ has elapsed (22) is turned OFF. As a result, the second and third motors (12) and (13) are turned off, but the sun gear (5) and the internal gear (6) gradually decelerate while rotating by inertia and eventually stop. After a time lag (T ₁ −T ₂ ) after turning off the second timer (22), this time the first timer (21)
Turns off. As a result, the first motor (11) is turned off, but the upper and lower platens (1) and (2) are rotating with inertial force while gradually decelerating. ) Continues to be polished. The polishing direction of the object to be polished (B) is made constant by the processing after the holder of the object to be polished (7) is stopped, and the polishing traces of the obtained polished product are aligned in a certain direction. For comparison, FIG. 4 shows a conventional sun gear (5), internal gear (6), upper and lower stool (1).
The operation characteristic of (2) is shown.

According to the present invention, as described above, the rotation of the grindstone is stopped after a predetermined time lag after the rotation stop rotation of the holder to be polished, so that the holder is stopped just before the end of the polishing process. In this state, there occurs a period in which only the grindstone is rotated and processing is performed. Therefore, the polishing marks on the polished product after the processing can be aligned in a certain direction, and the members whose uniformity of the polishing marks such as the Al substrate for magnetic disk etc. is required as the product quality can be reliably manufactured and provided with high yield. it can.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a planar polishing apparatus, FIG. 2 is a perspective view of a main part, FIG. 3 is an operation characteristic diagram, and FIG. (A) Planar polishing apparatus, (B) Polished object, (1)
... Upper platen, (2) ... Lower platen, (3) ... Upper grindstone, (4) ... Lower grindstone, (5) ... Sun gear, (6)
... internal gear, (7) ... holder to be polished.

Claims (2)

(57) [Claims] An object to be polished is provided with a pair of grindstones rotatably provided, and a holder for an object to be polished, which is rotatable between the grindstones and revolved. In a planar polishing apparatus configured to perform polishing of an object to be polished by rotating the grindstone pressed against the object to be polished, a predetermined time lag is provided after the rotation of the holder to be polished is stopped, and the rotation of the stone is performed. A polishing mechanism provided with a mechanism for stopping the polishing. 2. A workpiece holder is rotated while rotating between a pair of rotatably provided grinding wheels, and the workpiece is polished by rotating the grinding stone pressed against the workpiece. In the method of manufacturing a polished product, after the rotation of the holder for the object to be polished is first stopped, the rotation of the grindstone is stopped after a predetermined time lag, and the polished product in which the direction of the polishing marks is uniform. Manufacturing method.