JPH0659628B2 - Polishing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a non-contact polishing apparatus for finishing a flat surface portion or a curved surface portion of various optical elements, magnetic recording components and the like with high accuracy.

[Conventional technology]

Japanese Patent Laid-Open No. 61-71950 has been proposed as a conventional non-contact polishing apparatus. In this proposal, a surface plate (polishing dish) is rotated, and a workpiece generated with dynamic pressure by a groove provided in the surface plate is polished while being levitated. With such a configuration, it is suitable for polishing a planar work, but is not suitable for non-contact polishing of a curved surface.

[Problems to be solved by the invention]

The above-mentioned conventional technique has a problem that the surface of a work having a curved shape cannot be polished in a non-contact state.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a polishing apparatus capable of efficiently polishing not only a flat surface but also a curved surface shape in a non-contact state.

[Means for solving problems]

The purpose is to polish a polishing tool of a workpiece by ejecting an abrasive liquid pressurized by a pump toward the workpiece from a hole in the center, and between the workpiece and the tool. A motor for adjusting and controlling the gap on the basis of a signal from the gap control device, and the gap control for controlling the gap detected by the pressure detector of the pressure of the abrasive liquid through the motor so that the pressure becomes a predetermined value. And a polishing device provided with the device.

[Action]

For polishing in a non-contact state, it is necessary to supply the abrasive liquid 5 to the surface to be polished at high speed. For this purpose, it is necessary to eject the abrasive grain liquid 5 from the hole 4 of the tool 3 at a constant flow rate while keeping the tool 3 in a minute gap on the surface to be polished. The minute gap can be set by detecting the pressure of the abrasive grain liquid 5 in the tool 3 by the pressure detector 8. Therefore, as described in the description of the embodiments below, the gap between the work 1 and the tool 3 when the work 1 is a flat surface is controlled by the gap control device 9 and is adjusted and polished by the rotation of the motor 11. It When the surface to be polished is a curved surface, the gap 12 is controlled by the inclination control circuit 27 and the gap control circuit 26 of the control device 25 to adjust the pressure of the abrasive liquid 5 for polishing.

〔Example〕

An embodiment of the polishing apparatus of the present invention will be described below with reference to FIGS. FIG. 1 is an explanatory diagram of the overall configuration, and FIG. 2 is a perspective view of FIG. In the figure, 1 is a work, which is placed on a table 2. A tool 3 for polishing the upper surface of the work 1 is provided with a hole 4 for guiding the abrasive grain liquid 5 in the vertical center, and the abrasive grain liquid 5 is supplied from a pump 6 through a pipe 7. A pressure detector 8 for detecting the pressure inside the abrasive grain liquid 5 is attached to the pipe 7, 9 is a clearance control device, 10 is a support base of the tool 3, 11 is a support base according to a signal from the clearance control device 9. It is a motor for moving 10 up and down. Reference numeral 12 denotes a gap between the tool 3 and the work 1, and the abrasive grain liquid 5 pumped from the pump 6 is blown into the gap 12 at a high speed. Reference numeral 13 is a tank for storing the abrasive grain liquid 5, and the fine abrasive grains and the polishing liquid are mixed and stored in the tank 13. FIG. 3 is an explanatory diagram of the relationship between the pressure and the gap, where the gap (12) h is plotted on the horizontal axis and the pressure p is plotted on the vertical axis, and shows changes in pressure when the gap 12 is changed.

In the above structure, when the pump 6 is rotated, the abrasive liquid 5 is discharged through the pipe 7 through the hole 4 of the tool 3 into the gap 12 and then discharged. Since the gap 12 is sufficiently smaller than the inner diameter of the pipe 7 and the cross-sectional area of the hole 4, the abrasive liquid 5 passes through the gap 12 at a high speed of several tens to several hundreds m / min. When the abrasive liquid 5 passes through the gap 12, the surface of the work 1 is scraped off and polished. In polishing in such a non-contact state, the polishing amount varies depending on the magnitude of the flow velocity of the abrasive liquid 5. Therefore, it is important to polish while keeping the gap between the tool 3 and the work 1 small and constant.

Therefore, as shown in FIG. 3, by using the relationship between the value of the gap h and the pressure p, the tool 3 is adjusted so that the gap h is constant during polishing.
The position of is controlled in-process. In this method, when it is desired to set the gap h ₁ , the corresponding pressure p ₁
Is input to the gap control device 9 as a voltage value. In the gap control device 9, if the actual gap h is larger than h ₁ by the internal comparison circuit, the motor 11 is driven and the support base 10 of the tool 3 is lowered to match the gap h ₁ . Even when the table 2 is displaced and the work 1 is fed in one direction and polished, non-contact polishing can be efficiently performed by keeping the gap and pressure constant. The above embodiment is the work 1
An example of the case where the surface of the workpiece 1 is close to a planar shape is shown. Next, an embodiment in which the workpiece 1 is a curved surface will be described with reference to FIGS. 4 to 8.

FIG. 4 is an explanatory diagram of the overall configuration of an apparatus having a function of controlling the inclination of the work 1. In the figure, 14 is a driving motor for horizontally moving a table 15 on which the work 1 is placed in a moving section Δ formed to be larger than a section between the limit switches 21 and 22 of the tilting table 17. Reference numeral 16 is a crankshaft in which a moving section Δ can be set. Reference numeral 17 is a tilting table on which the table 15 is placed, which is the center of rotation
It has a mechanism that can be tilted around 18 as described later.
In addition, the dog 20 is fixed to the side surface of the table 15,
When the workpiece 20 moves in the tilt direction of the work 1, two limit switches 21 and 22 located at both ends of the tilt direction and abutting are fixed to the side surface of the tilt table 17, and the limit switches 21 and 22 are the dog 20. Is formed to emit a signal when abutting. The tilt table 17 is provided with a rotation center 18 at the center position in the tilt direction, and the rotation center 18
A spring 19 is arranged on one side of the tilt table 17 sandwiching 18 and a screw 23 driven by a tilt control motor 24 is screwed on a part of the other side. Reference numeral 25 is a control device for controlling the inclination of the gap 12 and the workpiece 1, and a circuit 26 for receiving a signal from the pressure detector 8 and controlling the gap amount inside, and a circuit 26.
And work 1 receiving signals from limit switches 21 and 22
Circuit 27 for controlling the movement of the inclination table 17 by determining the inclination of the
And are built in.

In the structure of FIG. 4, when the motor 14 is rotated, the table 15 is displaced left and right in the moving section Δ. Therefore, in FIG.
As shown in (a) and (b), the relative relationship between the polishing tool 3 and the work 1 changes. As shown in (a), when the work 1 is shifted to the right with respect to the tool 3 in the solid line position as shown by the arrow B, the time t is plotted on the horizontal axis and the operation timing of the limit switches 21 and 22 (R is the limit switch 22, L is a limit switch 21), and the gap 12 is narrowed as shown by a curve A in FIG. 6 in which the detected pressure p is plotted on the vertical axis, so that the pressure detected by the pressure detector 8 increases. On the other hand, when the work 1 is moved to the left as shown by the arrow C as shown in (B), the gap 12 is widened and the pressure shows a low value, which is repeated.

The relationship between the pressure p and the operation timing of the limit switches 21 and 22 when the work 1 is simply moved but the inclination of the work 1 is not changed in FIG. 5 is as shown in FIG. On the other hand, when the work 1 is horizontally displaced, whether or not the surface of the work 1 is inclined with respect to the surface of the tool 3
It can be detected by fluctuations in pressure. Moreover, the work 1 can be performed by the signals from the limit switches 21 and 22 provided on the left and right sides.
It can be determined in which direction the surface of the is inclined. Fifth
In the case of the figure, the detected pressure is high when the work 1 operates the right limit switch 22, and in this case, the surface of the work 1 facing the tool 3 is inclined downward to the right. Therefore, the motor 24 for tilt control is driven by the gap control circuit 26 and the tilt control circuit 27 on the basis of the detected pressure and the signals from the limit switches 21 and 22, and the tilt table 17 is moved to the position shown in FIG. Tilt in the direction of arrow D.
The state of the tool 3 and the work 1 after tilting is shown in FIG.

The tilt control is performed so that the fluctuation of the detected pressure becomes small, and this state is shown in FIG. 8 in which the horizontal axis and the vertical axis are the same as in FIG. 6, the dotted line E is before the tilt control, and the solid line F is the tilt control. The detected pressure after that is shown. In addition, when the tilt is controlled, the amount of gap changes, and therefore, as shown in FIG.
11 (not shown in FIG. 4) is operated to control the position of the tool 3. Therefore, the pressure of the gap 12 between the tool 3 and the work 1 is constantly detected and adjusted to a predetermined gap, and the tool 3 is attached to the work 1 via the support base 10 so that the predetermined pressure is maintained.
Adjust the position of automatically. Therefore, when the surface to be polished of the work 1 is a curved surface, an efficient polishing operation can be performed within a fluctuation range in which the pressure of the abrasive liquid 5 ejected is extremely small.

Thus, the polishing apparatus of the present embodiment, when the surface to be polished is a flat surface, the gap between the tool and the work is detected by controlling the pressure of the abrasive liquid and controlled to perform more polishing at a predetermined pressure, When the surface to be polished is a curved surface, the gap between the workpiece and the tool is also detected through pressure, and the inclination of the curved surface is detected to control the inclination and control the posture of the workpiece so that it always has a predetermined clearance. And efficient polishing is possible.

〔The invention's effect〕

As described above, the polishing apparatus of the present invention has the effect of efficiently polishing not only a flat surface but also a curved surface in a non-contact state.

[Brief description of drawings]

FIG. 1 is an explanatory view of the overall configuration of an embodiment of a polishing apparatus of the present invention, FIG. 2 is a perspective view of FIG. 1, and FIG. 3 is a relation between a gap between a tool and a work of the apparatus of FIG. 1 and pressure. Explanatory drawing, FIG. 4 is a general structural explanatory view of another embodiment of the polishing apparatus of the present invention, and FIG.
Figures (a) and (b) are explanatory views of the gap change between the work and tool of the device in FIG. 4, respectively, and FIG. 6 is an explanation of the relationship between the detected pressure and the limit switch signal in the case where the clearance is not adjusted in FIG. FIGS. 7 and 7 are explanatory views after the inclination control of the work of FIG. 4, and FIG. 8 is an explanatory view of the relationship between the detected pressure and the limit switch signal in the case of the inclination control of FIG. 1 ... worm, 3 ... tool, 4 ... hole, 5 ... abrasive liquid, 6 ... pump, 8 ... pressure detector, 9 ... gap control device, 11 ... motor, 12 ... gap , 15 …… table, 17 …… tilt table, 18 …… rotation center, 19 …… spring, 20 …… dog, 21,22 …… limit switch, 23 …… screw, 24 …… motor, 25 …… control Device, 26, 27 ... Circuit.

Claims (2)

[Claims] 1. A polishing tool formed so as to process a polishing surface of a work by ejecting an abrasive liquid pressurized by a pump toward a work from a central hole, and the work and the space between the tools. A motor for adjusting and controlling the gap of the gap based on a signal from a gap controller, and the gap for controlling the gap through the motor so that the pressure of the abrasive liquid is detected by a pressure detector and the gap becomes a predetermined value. A polishing device provided with a control device. 2. A tilt table is provided which slidably mounts on the upper surface of a table for fixing the work, which is formed by an inclined curved surface, to the upper surface via a driving member in the tilt direction. The tilt table is provided with two limit switches fixed at the two ends of the dock fixed to the side surface of the table by moving in the tilt direction. A spring is provided on one side of the tilt table sandwiching the center of rotation in the tilt direction, and a screw driven by a motor for tilt control is screwed into a part of the other side of the tilt table to drive the center of rotation by driving the motor. Based on the signals from the pressure detector and the limit switch, the rotation of the motor for tilt control, the direction of rotation, and the gap are set to be swingable around the center. Polishing apparatus for circuit and scope Claim 1 wherein the formation has been have claimed to control by a control device having a circuit for controlling the tilt of the tilting table to control the amount of.