JPS6117626B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a small-sized apparatus for simultaneously polishing both sides of a plurality of ultra-thin plates into parallel planes with high accuracy.

Conventional polishing devices of this type include those in which a carrier holding a workpiece is driven by an eccentric pin, and those in which a carrier is driven by a differential gear. This will be explained using drawings.

Fig. 1 shows an eccentric pin drive type polishing device, in which a hole is provided on an annular lower polishing plate 1 to fit with an eccentric pin 3 provided on a drive shaft 2, and the hole has the same diameter as the average diameter of the lower polishing plate 1. A carrier 5 having a plurality of workpiece holes 4 on the circumference is arranged, and after mounting the workpieces in the workpiece holes 4, an upper polishing plate 7 is placed on the top, and an abrasive is dripped onto the carrier 5. When the drive shaft 2 is rotated, the workpiece 6 held by the carrier 5 swings in a circle via the eccentric pin 3. This allows both surfaces to be polished at the same time.

Figures 2a and 2b are a plan view and a front cross-sectional view of the main parts of a differential gear drive type polishing device, and in these figures, 8 is a center gear, and 9 is an internal gear. 1, and parts with the same reference numerals as in other FIG. 1 indicate the same parts.

A plurality of carriers 5 having a plurality of workpiece holes 4 and a gear-shaped outer periphery are engaged with a center gear 8 and an internal gear 9, and are arranged evenly on the lower polishing plate 1. After installing the workpiece 6 in the workpiece hole 4 of the carrier 5, place the upper polishing plate 7 on the top and rotate the center gear 8 and internal gear 9 while dropping the abrasive. 5
rotates and revolves around center gear 8,
Along with this, a predetermined machining motion is applied to the workpiece 6, and both surfaces are simultaneously polished.

According to the conventional polishing apparatus shown in FIGS. 1 and 2, when lapping uses coarse abrasive grains as the abrasive, the carrier 5 can be processed without being damaged because the processing resistance is relatively small, but fine abrasive grains In polishing using a processing agent, when the workpiece 6 becomes a mirror surface, the polished surface comes into close contact with the polishing plate, increasing the processing resistance. For example, when processing a workpiece 6 with a thickness of 10 μm, the processing resistance is 5, the carrier 5 is damaged and the workpiece 6 is destroyed, making it impossible to process the workpiece.

In order to solve these drawbacks, this invention holds a carrier that holds the workpiece in a rotary manner and polishes it while swinging, thereby polishing both sides of an ultra-thin plate that requires highly accurate parallel planes. This allows for simultaneous polishing. This invention will be explained above.

FIGS. 3a and 3b show an embodiment of the present invention, and are a partially cutaway plan view and a front sectional view.

A carrier 5 is installed on the surface of a ring-shaped lower polishing plate 1 whose rotation is transmitted by a drive shaft 2b.
To install the carrier 5, use the upper and lower ring bodies 10 and 11.
In the meantime, the carrier 5 is fixed with the screw 12, and then the male thread on the outer periphery of the ring-shaped fixture 13 is screwed into the male thread formed inside the ring body 11. Gradually push the so-called carrier 5 up. Thereafter, the carrier 5 is formed with a hole 4 for the workpiece and a relief hole 14 in the center thereof through which the drive shaft 2b is inserted. Reference numeral 15 denotes a base, to which a ring-shaped fixing member 16 is attached, and a ring-shaped rotating member 17 is screwed into a male thread formed on the inner surface of the base.
The upper surface of the rotating member 17 is a sliding surface 18,
The height of this sliding surface 18 is adjusted by rotating the rotating member 17. A carrier holder 19 is mounted on the sliding surface 18 via a sliding ball bearing.
is placed thereon, and the fixture 13 is fitted into the recess formed on the upper surface of the carrier holder 19 via the ball 191. The ball 191 is provided to facilitate the relative rotation of the recessed portions of the attachment 13 and the carrier holder 19, and as long as it has this function, it does not necessarily have to be a ball; If the friction between the carrier support 19 and the carrier support 19 is formed to be small, the ball can be removed without using the ball.
It may remain as a relatively easy slip surface. Thus, by adjusting the height of the sliding surface 18, the relative position of the upper surface of the lower polishing plate 1 and the carrier 5 raised from the outer periphery can be aligned. A connector 20 is attached to the carrier holder 19.
The connector 20 is connected via a fulcrum pin 21 to an eccentric pin 3 with variable eccentricity attached to the drive shaft 2c. A large number of workpieces 6 are arranged in the workpiece holes 4 of the carrier 5 installed in this manner, and an upper polishing plate having the same shape as the lower polishing plate 1 is placed on the rotating body 22 which is key-driven by the drive shaft 2a. The plates 7 are connected and placed on the workpiece 6.

The swinging shape of the workpiece 6 held by the carrier 5 and swinging is determined by the distance from the rotation center of the eccentric pin 3 to the fulcrum pin 21 and the distance from the fulcrum pin 21 to the carrier 5.
It is determined by the distance to the center of the hole 4, and if both are the same, it will be a circular swing, and if they are different, it will be an elliptical swing.
Further, by changing the amount of eccentricity of the eccentric pin 3, the swing range can be changed. In FIG. 3, the relationship between the distance from the rotation center of the eccentric pin 3 to the fulcrum pin 21 and the distance from the fulcrum pin 21 to the center of the hole 4', which is the center of the three holes shown in the carrier 5, is shown. Since this is a case where the ratio is 1:2, the eccentric pin 3 traces a circular locus 3', and the center point of the workpiece 6 held by the carrier 5 traces an elliptical locus 6'.

In operation, a prime mover (not shown) connected to each drive shaft 2a, 2b, 2c supplies the abrasive.
When power is applied, the upper and lower polishing plates 7 and 1 rotate at the same speed and in reverse to each other, while the workpiece 6 held by the carrier 5 swings, and both sides of the workpiece 6 are simultaneously polished. Moreover, since the carrier 5 is supported by a rolling bearing via the fixture 13, it rotates in response to slight differences in the abrasive resistance applied to both sides of the workpiece 6, and the abrasive resistance on both sides of the workpiece 6 is balanced. is maintained. Therefore, even if the carrier 5 is made of a thin film, there will be little damage, and even extremely thin plates can be polished.

Actually, diameter 8 to 12 is used as piezoelectric filter.
We were able to obtain a hard and brittle parallel plane ultrathin plate of lithium tantalate with a thickness of approximately 20 μm.

Note that the workpieces 6 do not necessarily have to be installed in all of the workpiece holes 4 as long as they are arranged so as to be balanced in the workpiece holes 4.

As described above in detail, the present invention includes a carrier in which a thin plate holding an ultra-thin plate-shaped workpiece is stretched up in a drum shape is rotatably held in a carrier holder, and the carrier holder is made to swing. Therefore, even if there is a difference in polishing resistance between the upper and lower polishing plates, the carrier rotates and automatically balances the polishing resistance, so that no undue force is applied to the carrier. Never. Furthermore, since it has an extremely simple configuration, there is no need for complicated control, and it has the advantage of being low cost and easy to maintain and operate.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway front view of a conventional eccentric pin drive type polishing device, and Figures 2a and b are a plan view and front cross section of a conventional differential gear drive type polishing device with main parts cut away. 3A and 3B are a partially broken plan view and a front sectional view showing an embodiment of the present invention. In the figure, 1 is the lower polishing plate, 2a, 2b, 2c are the drive shafts, 3 is the eccentric pin, 4 is the hole for the workpiece, 5 is the carrier, 6 is the workpiece, 7 is the upper polishing plate, 13 is the mounting 18 is a sliding surface, 19 is a carrier receiver, 20 is a connecting tool, 21 is a fulcrum pin, 22 is a rotating body, 191
is a bearing ball.

Claims (1)

[Claims] 1. An upper polishing plate and a lower polishing plate that face each other and rotate at a constant speed in opposite directions, and a plurality of extremely thin plate-shaped workpieces are held between the polishing plates, and the workpiece is slightly thinner than the thickness of the workpiece. The present invention comprises a carrier made of a drum-shaped sheet stretched up, a carrier holder that rotatably supports the carrier via a plurality of balls or easy sliding surfaces, and means for swinging the carrier holder. A device for simultaneously polishing both sides of an ultra-thin plate.