JP2001105201A - Method of manufacture for contact lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To process a contact lens as an object to be manufactured with high accuracy and high efficiency in manufacture of contact lens. SOLUTION: Manufacturing process for a contact lens 4 is divided into two for an internal circumferential part being a base curve part and for an outer circumferential part. When the internal circumferential part is processed, it is processed by revolution of a swiveling table 7. When the outer circumferential part is processed, the swiveling table 7 that loads a tool 5 stops revolving and the outer part is processed by moving of orthogonal X-Y tables 1 and 2 loading a spindle 3 that revolves the contact lens being an object to be manufactured. Consequently, the contact lens can be manufactured with high accuracy and high efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a contact lens.

[0002]

2. Description of the Related Art Conventionally, a contact lens manufacturing apparatus is shown in FIG.
As shown in FIG. 3, a spindle 3 for rotating a contact lens 4 as a workpiece is fixed on a base plate 8, and a turning table 7 for turning a tool 5 to perform spherical processing is provided on the base plate at a position opposed to the spindle 3. 8 was fixed on. Or, as shown in FIG. 3, an X-table 2 and a Y-table 1 which are orthogonally controlled by NC instead of the turning table.
Was fixed on a base plate 8 and the tool 5 was arranged thereon. Alternatively, as shown in FIG. 4, the swivel table 41 is arranged on the X table 2 and the Y table 1 which are orthogonally controlled by the NC.

[0003]

The contact lens has a shape as shown in FIG. 5, and even if the shape of the contact lens is an example of a concave surface side, R1 (hereinafter referred to as a base) which determines the optical characteristics of the lens. Curve 52), R2 (hereinafter referred to as a secondary curve) 52 that promotes the circulation of tears, and outermost portion R3 that controls the feeling of wearing a contact lens.
Curves R4.5 that connect the intersections of these three curves with an inverted R (hereinafter referred to as peripheral curves) 53
4, made of curve R5.55. However, in the prior art described above, in FIG. 2, the shape of the contact lens 4 is not completed only by turning the turning table 7 once,
The base curve, secondary curve, peripheral curve and three turns must be turned. In FIG. 3, in order to obtain a shape accuracy and a surface roughness satisfying the optical characteristics at the center, a very high motion accuracy is required for the XY table controlled by the NC. Further, in FIG. 4, since the height from the base plate 8 to the contact lens 4 is increased, there is a problem that it is difficult to secure the motion accuracy of the tool 5. Therefore, the present invention solves such a problem.
An object of the present invention is to provide a contact lens manufacturing method for processing the contact lens with high accuracy and high efficiency.

[0004]

In order to solve the above-mentioned problems, a contact lens manufacturing method according to the present invention comprises a contact lens manufacturing method in which a contact lens as a workpiece is rotated by a spindle to process the contact lens. A step of processing a base curve portion as an inner peripheral portion, and a step of processing an outer peripheral portion thereof. In the step of processing the base curve portion, a turning table mounted with a tool for processing the contact lens is turned. In the step of processing the outer peripheral portion,
The turning table stops turning, and the orthogonal XY table on which the spindle is disposed moves in the orthogonal XY direction to perform machining.

According to the structure of the present invention, a swivel table for machining a base curve portion requiring spherical accuracy and surface roughness and an NC controlled orthogonal XY for machining an outer peripheral portion having a complicated shape.
Since the processing steps can be divided into the table portion, the contact lens can be efficiently processed by one rotation.
In addition, since the swivel table and the XY table controlled by the NC are separately arranged, the restriction of inferior mechanical accuracy due to an increase in the height of the structure can be reduced, and the structure of the swivel table can be freely adjusted. Since the degree of increase is increased, it is possible to adopt a turning table having good positioning accuracy and movement accuracy, and it is possible to improve the shape accuracy and surface roughness of the contact lens.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, a contact lens 4 which is a workpiece
Is supported by a vacuum chuck 14 by a vacuum introduced from a vacuum source 12 via a rotary seal 13, and the vacuum chuck 14 is attached to the air spindle 3 and can rotate at high speed. Placed on table 2 and Y table 1, NC
It moves under numerical control by the device 15. On the other hand, a tool 5 for processing the contact lens 4 is a vertical moving table 10 for adjusting the height of the contact lens 4.
The vertically moving table 10 is set on the R table 6 for determining the turning radius of the tip of the tool 5, and the entire R table 6 turns on the turning table 7. The block on the turning table 7 side and the block on the Y table 1 side are arranged on the same base board 8.
The turning table 7 is constituted by an air spindle. The air spindle employs a large-volume air spindle for high rigidity, and is completely closed-loop controlled by a rotary encoder 16 for improving positioning accuracy. By forming the turning table 7 by an air spindle, a turning table with good rotational movement accuracy and no vibration can be obtained, and a base curve portion requiring optical characteristics can be finished with a good surface. At this time, the structure of the air spindle is large and high due to the problem of rigidity as described above. However, since the block on the turning table 7 side and the block on the Y table 1 side are separated, from the base plate 8 to the contact lens 4 Height can be reduced, which helps maintain the accuracy of the machine.

[0006]

The contact lens manufacturing apparatus according to the present invention comprises:
As described above, when processing the outer peripheral portion of the contact lens, the turning table stops turning, the spindle is mounted, and the orthogonal XY table that moves the spindle in the orthogonal XY direction moves. By doing processing
In the conventional machining method, the turning table is required to be turned a plurality of times, but it is possible to perform the machining with a single turn.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a manufacturing apparatus according to the present invention.

FIG. 2

FIG. 3

FIG. 4 is a longitudinal sectional view of a conventional manufacturing apparatus.

FIG. 5 is a longitudinal sectional view of an example of the shape of a contact lens.

[Explanation of symbols]

 Reference Signs List 1 Y table 2 X table 3 Spindle 4 Workpiece (contact lens) 5 Tool 6 R table 7 Rotating table 8 Base board 10 Vertical movement table 12 Vacuum source 13 Rotary seal 14 Vacuum chuck 15 NC 16 Rotary encoder

Claims (1)

[Claims] 1. A contact lens manufacturing method for processing a contact lens, which is a workpiece, by rotating the spindle by a spindle. In the step of processing the base curve portion, a turning table mounted with a tool for processing the contact lens is turned to perform processing, and in the step of processing the outer peripheral portion, the turning table is A method of manufacturing a contact lens, comprising: stopping rotation, and moving the orthogonal XY table on which the spindle is disposed in an orthogonal XY direction to perform processing.