EYEGLASS LENS PROCESSING APPARATUS

• US 20120083186A1
• Filed: 09/29/2011
• Published: 04/05/2012
• Est. Priority Date: 09/30/2010
• Status: Active Grant

• Current Assignee: Nidek Company Limited
• Original Assignee: Nidek Company Limited
• Inventors: SHIBATA, Ryoji
• Granted Patent: US 9,925,635 B2
• Time in Patent Office: Days
• US Class Current: 451/5
• CPC Class Codes: B24B 47/22 Equipment for exact control of the position of the grinding tool or work at the start of the grinding operation
• CPC Class Codes: B24B 49/02 according to the instantaneous size and required size of the workpiece acted upon, the measuring or gauging being continuous or intermittent B24B49/12 takes precedence
• CPC Class Codes: B24B 51/00 Arrangements for automatic control of a series of individual steps in grinding a workpiece if applicable to other machine tools, G05B takes precedence
• CPC Class Codes: B24B 9/14 of optical work, e.g. lenses, prisms control of the position of the tool for bevelling optical work B24B47/225
• CPC Class Codes: B24B 9/144 the spectacles being used as a template
• CPC Class Codes: B24B 9/148 electrically, e.g. numerically, controlled

Abstract

In an eyeglass lens processing apparatus, if a material selector selects a thermoplastic material for the lens, a control unit performs a first step and then a second step. In the first step, the control unit controls a lens rotating unit to position a lens in a plurality of lens rotation angles and controls an axis-to-axis distance changing unit to cause a roughing tool to cut into the lens up to a roughing path for each of the plurality of lens rotation angles, the lens being not rotated by the lens rotating unit when the roughing tool is cutting into the lens up to the roughing path. In the second step, the control unit controls the lens rotating unit and the axis-to-axis distance changing unit to rough the lens based on the roughing path while the lens rotating unit rotates the lens.

Claims

1. An eyeglass lens processing apparatus comprising:

a lens rotating unit including a lens chuck shaft for holding an eyeglass lens and a motor for rotating the lens chuck shaft;

a processing tool rotating unit including a roughing tool for roughing a periphery of the lens, a processing tool rotating shaft to which the roughing tool is attached, and a motor for rotating the processing tool rotating shaft;

an axis-to-axis distance changing unit including a motor for changing an axis-to-axis distance between the lens chuck shaft and the processing tool rotating shaft;

a control unit configured to obtain roughing path based on a target lens shaft, and control the lens rotating unit and the axis-to-axis distance changing unit based on the obtained roughing path to rough the periphery of the lens by the roughing tool,

wherein the control unit performs a first step and then a second step,

wherein in the first step, the control unit controls the lens rotating unit to position the lens in a plurality of lens rotation angles and controls the axis-to-axis distance changing unit to cause the roughing tool to cut into the lens up to the roughing path for each of the plurality of lens rotation angles, the lens being not rotated by the lens rotating unit when the roughing tool is cutting into the lens up to the roughing path, and

wherein in the second step, the control unit controls the lens rotating unit and the axis-to-axis distance changing unit to rough the lens based on the roughing path while the lens rotating unit rotates the lens.

2. The eyeglass lens processing apparatus according to claim 1, wherein

in the first step, after the roughing tool cuts into the lens up to the roughing path while not rotating the lens, the control unit controls the axis-to-axis distance changing unit to separate the lens from the roughing tool, controls the lens rotating unit to rotate the lens by a predetermined angle, controls the axis-to-axis distance changing unit to cause the roughing tool to cut into the lens up to the roughing path again while not rotating the lens, and repeats these processes in the plurality of lens rotation angle directions until the lens rotates once under these processes.

3. The eyeglass lens processing apparatus according to claim 2, wherein

the predetermined angle is set within a range from 30 degrees to 80 degrees.

4. The eyeglass lens processing apparatus according to claim 3, wherein

the plurality of lens rotation angles are angles obtained by dividing one rotation of the angle by 5 to 12.

5. The eyeglass lens processing apparatus according to claim 3, wherein

the plurality of rotating angles are stored in a memory as predetermined values.

6. The eyeglass lens processing apparatus according to claim 3, wherein

the control unit sets the plurality of rotating angles based on a diameter of the roughing tool, the roughing path or a target lens shape, and a diameter of the unprocessed lens.

7. The eyeglass lens processing apparatus according to claim 6, wherein

the control unit sets the plurality of rotating angles so that the entire periphery of the lens is processed by the roughing tool at the first step.

8. The eyeglass lens processing apparatus according to claim 6, wherein

the control unit sets the plurality of rotating angles so that a distance between a chuck center of the lens chuck shaft and a roughing region where the roughing tool roughs the lens in the first step is equal to or less than a predetermined distance which is smaller than a radius of the lens and at which an axial deviation between the lens and the lens chuck shaft does not occur at the second step.

9. The eyeglass lens processing apparatus according to claim 6, wherein

the plurality of lens rotation angles are angles obtained by dividing one rotation of the angle by 5 to 12, and an interval of the adjacent angles are within a range between 30 degrees and 80 degrees.

10. The eyeglass lens processing apparatus according to claim 1 further comprising a material selector configured to select material of the lens,

wherein if the material selector selects a thermoplastic material for the lens, the control unit performs the first step and then the second step, wherein

in the second step of roughing, the control units controls the lens rotating unit to rotate the lens in the same direction as the rotation direction of the roughing tool.

11. The eyeglass lens processing apparatus according to claim 10, wherein

if the material selector selects a lens of thermoset material, the control unit performs the second step,

in the second step, the control unit controls the lens rotating unit to rotate the lens in a direction opposite to a rotating direction of the roughing tool.

12. The eyeglass lens processing apparatus according to claim 1, wherein

the control unit controls the axis-to-axis distance changing unit so that a cutting-in speed of the roughing tool at the first step is set to equal to or less than a predetermined allowable value.

13. The eyeglass lens processing apparatus according to claim 1 further comprising a processing mode selector configured to select a first mode in which a surface of the lens is slippery and a second mode in which the surface of the lens is normal,

wherein the control unit controls the axis-to-axis distance changing unit so that the cutting-in speed of the roughing tool at the first step in the second mode is faster than that of the first mode, and controls the lens rotating unit so that the rotating speed of the lens at the second step in the second mode is higher than that of the first mode.