JPH0724716A - Lens grinding device - Google Patents

Abstract

PURPOSE:To simplify a device structure and shorten setup time by measuring and calculating the curvature radius and thickness of lens material according to a specified program and, based on the results, instructing the polishing correction of the lens material and the replacement of various grinding wheels. CONSTITUTION:A rough polishing grinding wheel on a mounting table 18 is held and transported by a grinding wheel chuck 16, and installed on a grinding wheel shaft 15. Then it polishes a lens 24 held in a lens holder 10 to a preset curvature radius and thickness by the rough polishing grinding stone which is numerically controlled by a program preset with respect to an ordinate axis 5, a abscissa axis 8, and an oscillating axis 12. It is measured by a simplified spherical surface meter mounted on the mounting stand 18 whether the rough polished lens 24 is polished in a specified shape or not. Then an error from the preset value of spherical surface is calculated to judge whether a corrective polishing is required or not. When the corrective polishing is required, polishing correction is instructed and, when it is not required, change of the rough polishing grinding wheel to a medium polishing one is instructed. In the same manner, the medium polishing grinding stone is also changed to a finishing grinding wheel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus for optical materials.

[0002]

2. Description of the Related Art For example, there is a lens polishing apparatus described in Japanese Patent Publication No. 44-23277. In this conventional example, each of the rough polishing wheel, the medium polishing wheel, and the finishing polishing wheel is attached to a polishing wheel shaft different from each other, and each polishing wheel shaft is moved forward and backward in the direction of the material to be polished with a time lag between The structure is such that the material to be polished is polished to perform rough polishing, middle polishing and finish polishing in sequence.

[0003]

In the conventional structure described above, various types of grindstones such as a rough grindstone are mounted on separate grindstone axes, that is, a rough grindstone axis, a medium grindstone axis and a finish grindstone axis. Therefore, not only the structure becomes complicated, but also there are various problems that it takes time to set up the polishing operation, the maintenance cost of the apparatus increases, and the cost of the equipment increases.

The present invention was devised in view of the drawbacks of the conventional example, and provides a device having a simple device structure, a short setup time, and low device maintenance costs and equipment costs. With the goal.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to an apparatus for polishing a lens material to have a predetermined radius of curvature and a predetermined thickness, in which a lens material is ground according to instructions of a predetermined program. Grinding stone exchanging means for converting various grinding stones for finish polishing, according to instructions of a predetermined program, measuring radius of curvature of the lens material, measuring means for performing arithmetic processing, and based on the measurement calculation result of the measuring means, The polishing correction of the lens material includes a control means for instructing replacement of a grindstone.

[0006]

Embodiment 1 FIGS. 1 to 6 show Embodiment 1 of the present invention. FIG. 1 is a side view, FIG. 2 is a partially enlarged view of a polishing portion of FIG. 1, and FIG. FIG. 4, FIG. 4 is a front view, FIG. 5 is a plan view, and FIG. 6 is a partially cutaway perspective view.

In FIG. 1, reference numeral 24 denotes a lens material or a lens block to be processed (hereinafter simply referred to as a lens),
The lens 24 is held by the lens holder 10 at the lower end. The lens holder 10 is linked to a work rotation motor 11 disposed above the lens holder 10, and is freely rotated by driving the work rotation motor 11, and the number of rotations can be freely changed by a controller (not shown). Is being done.

The lens holder 10 and the work rotation motor 11 together with the attachment / detachment vertical cylinder 17 and the grindstone attachment / detachment chuck 16 constitute a work shaft portion, and the work shaft portion is movable in the Y direction shown in the drawing by a horizontal axis drive servomotor 9. It is fixed to the horizontal axis 8. Further, the horizontal axis 8 is connected to the vertical axis 5 which is movable in the Z direction by the vertical axis drive servomotor 6, and the work shaft section is connected and attached to the column 2 via the vertical axis 5 and the horizontal axis 8. There is.

FIG. 15 shows a grindstone shaft disposed directly under the lens holder 10, and the grindstone shaft 15 is a rough polishing grindstone 19,
The medium grinding wheel 20 and the finishing grinding wheel 21 can be detachably mounted, and are linked with the grinding wheel rotation motor 14 to be freely rotated by the driving of the grinding wheel rotation motor 14 and the number of rotations thereof is not shown. It can be freely changed by the device. Also, the grindstone shaft 15
The portion is connected and fixed to a swing shaft 12 which is movably mounted in a direction A by a swing shaft drive servomotor 13.
The rotation center shaft 23 assembled to the column 2 is used as a center for pivoting along a receiving portion 25 provided on the column 2.

The lens 24 has the vertical axis 5,
The horizontal shaft 8 and the swing shaft 12 are driven by numerical control by a controller (not shown) so that the radius of curvature and the thickness can be freely adjusted.

The rough polishing whetstone 19, the middle polishing whetstone 20 and the finish polishing whetstone 21 are mounted on the mount 18 provided on the column 2.
It is detachably and replaceably attached to the mounting base 18, and a simple spherical meter 22 is mounted on the mounting base 18.

An attachable / detachable vertical cylinder 17 is attached to the work shaft portion, and a grindstone attaching / detaching chuck 16 is movably held on the attachable / detachable upper / lower cylinder 17, by which the abrasive grindstones 19, 20, 21 grindstones It is freely conveyed to the shaft 15, and can be fixed and released by a fixing actuator and a draw bar (not shown).

In the simple sphere meter 22, after the lens 24 is polished by the polishing grindstones 19, 20, and 21, the movement of the lens 24 is controlled by the vertical axis 5 and the horizontal axis 8, and the lens 24 is moved.
The machined surface of can be measured. In addition, as shown in FIG.
Is a pedestal, 3 is an electrical equipment box for controlling the entire apparatus, 4 is an operation box, and 7 is a balance cylinder provided to reduce the load of the vertical axis drive servomotor 6 of the vertical axis 5. The operation of the polishing apparatus of the embodiment will be described below.

The rough polishing grindstone 19 is a grindstone attaching / detaching chuck 16.
It is gripped and conveyed by and is attached to the grindstone shaft 15. The lens 24 held by the lens holder 10 has a radius of curvature set by the rough grinding wheel 19 by a numerically controlled operation of the vertical axis 5, the horizontal axis 8 and the swing axis 12 by a preset program. To be ground. In addition,
The thickness of the lens is created leaving a margin of about 0.03 mm of the finished thickness.

Then, the lens 24 rough-finished according to the program is measured whether or not it has been processed and polished into a predetermined lens shape. Therefore, a simple spherical meter mounted on the mount 18 by the vertical axis 5 and the horizontal axis 8 is measured. The measurement is carried out by moving to 22 measurement points. For the measurement data, the spherical surface created by an arithmetic processing device (not shown) calculates an error from the set value, and if it is outside the intersecting range, the vertical axis 6, the horizontal axis 8 and the swing axis 12 are based on the arithmetic processing data. It moves to the designated place (returns to the original position) and is re-polished to a regular radius of curvature.

Within the intersecting range, the grindstone attaching / detaching chuck 16 is moved by the vertical axis 5 and the horizontal axis 8 to move the grindstone axis 1
The rough grinding wheel 19 is gripped and conveyed from No. 5 and set on the mount 18. Hereinafter, the medium grinding wheel 20 and the finishing grinding wheel 21
The lens 24 is finished to have the set radius of curvature and thickness by similarly performing the polishing operation by.

The stock removal in polishing with a rough polishing grindstone is about 0.03 mm, but 0.01 m with a medium polishing grindstone.
It is created with a margin of about m left. Further, in the embodiment, the measurement with the simple sphere meter is carried out for each polishing by the grindstones 19, 20, 21. However, the sampling measurement can also be carried out. Furthermore, as a measurement unit, a simple spherical meter 2
Although the number 2 is shown, the lens thickness measuring unit may be equipped to control the lens thickness.

The present embodiment shows a two-system type on the drawing, and both the A-side and the B-side of the lens 24 can be processed, but the one-system type can of course be implemented.

[0019]

Second Embodiment FIG. 7 shows a second embodiment of the lens polishing apparatus of the present invention.
Indicates. The polishing apparatus of the second embodiment differs from that of the first embodiment in the arrangement contents of the respective grindstones for rough polishing, middle polishing and finish polishing in the first embodiment. The configuration will be described below. The rest of the configuration is the same as that of the first embodiment, and therefore its explanation is omitted.

In FIG. 7, reference numeral 31 denotes an index table. The index table 31 is rotatable by a cam indexing device (not shown) (in this embodiment, it is divided into 8 parts) and is attached to the column 2 via a mount 18. It is installed. The index table 31 has a pair of rough grinding wheels 32 and 3 for the A side and B side respectively.
5, middle polishing stones 33, 36 and finishing polishing stones 34,
37 is attached in a detachable and replaceable manner, and further, a simple sphere meter 38 and a wall thickness measuring device 39 are attached.

Then, the index table 31 is turned, the necessary grindstone is moved to the transfer position 40, and the grindstone attaching / detaching chuck 16 replaces the grindstone for machining.
When performing the wall thickness or spherical surface measurement operation, similarly, the index table 31 is swiveled to move the wall thickness measuring device 39 or the simple spherical surface meter 38 to the delivery position 40 for measurement, and an arithmetic processing unit (not shown) is used. In the same manner as in Example 1, reworking is performed with the grindstone.

In this embodiment, lenses of different types can be automatically machined continuously, and efficient lens production is possible. Note that the remaining points are the same as those in the first embodiment, so description thereof will be omitted.

[0023]

According to the lens polishing apparatus of the present invention, rough polishing, intermediate polishing, and finish polishing can be automatically performed without attaching or detaching the lens from the apparatus, so that the number of working steps associated with attachment and detachment can be further reduced. Eliminates the deterioration of the thickness of the radius of curvature associated with the attachment and detachment, and a great amount of setup time, which improves the lens accuracy and enables even an unskilled person to perform short-time processing.

[Brief description of drawings]

FIG. 1 is a side view.

FIG. 2 is a partially enlarged view of a polishing portion of FIG.

FIG. 3 is a partially enlarged view of the mounting base portion of FIG.

FIG. 4 is a front view.

FIG. 5 is a plan view.

FIG. 6 is a partially cutaway perspective view.

FIG. 7 is a partially cutaway plan view showing a second embodiment.

[Explanation of symbols]

 4 Operation Box 5 Vertical 6 Vertical Axis Drive Servo Motor 8 Horizontal Axis 9 Horizontal Axis Servo Motor 10 Lens Holder 11 Work Rotation Motor 12 Oscillation Axis 13 Oscillation Axis Drive Servo Motor 14 Grindstone Rotation Motor 15 Grindstone Axis 16 Grindstone Attachment / Detachment Chuck 17 Attachment / Detachment Upper and lower cylinder 24 Lens material

Claims (1)

[Claims] 1. An apparatus for polishing a lens material to have a predetermined radius of curvature and a predetermined thickness, the grindstone exchange for converting various types of grindstones for rough polishing, medium polishing and finish polishing for polishing a lens material according to instructions of a predetermined program. And a measuring means for measuring and calculating the radius of curvature and thickness of the lens material according to means of a predetermined program, and based on the measurement calculation result of the measuring means, polishing correction of the lens material, replacement of a grindstone, etc. And a lens polishing device having control means for instructing.