Processing device and processing method suitable for processing multiple lens blanks into finely ground products

Abstract

A processing device suitable for processing multiple lens blanks into a finely ground product, the processing device including two processing fixtures, each including a fixture body with a curved surface. There are three grooves having centers disposed on the same circumferential surface. One of the processing fixtures corresponds to the inner surface of the groove as a flat surface, and the other processing fixture corresponds to the concave surface of the groove as a curved surface. The invention also discloses a method for processing a plurality of lens blanks into a finely ground product by using the processing device. The invention can directly perform the fine grinding processing of multiple cylindrical lens blanks, thereby eliminating a milling process and reducing the production cost while meeting the required thickness, radius of curvature and appearance of the finished product.

What is claimed herein is: 
     
         1 . A processing device for processing a plurality of lens blanks into finely ground products, said processing device comprising two processing fixtures, each of said two processing fixtures comprises a fixture body comprising a curved surface, three grooves each comprising a center, said three grooves are configured such that said centers are disposed on said curved surface of each said processing fixture, wherein a first of said two processing fixtures comprises a surface of each of said three grooves that is a flat surface and a second of said two processing fixtures comprises a surface of each of said three grooves that is a curved surface. 
     
     
         2 . The processing device according to  claim 1 , wherein each said groove of said first and second of said two processing fixtures comprises a plastic annular ring fixed on an inner side wall of each said groove by a glue. 
     
     
         3 . The processing device according to  claim 1 , wherein the depths of said three grooves of are the same for each said processing fixtures and the depths of said three grooves are based on an arc-shaped curved surface of each said processing fixtures. 
     
     
         4 . The processing device according to  claim 1 , further comprising a fine grinding mold comprising an arc-shaped groove with an opening at one end and a handle configured to be fixedly connected to an external rotating shaft. 
     
     
         5 . The processing device according to  claim 4 , wherein the curvature of an arc working surface of said fine grinding mold is consistent with the curvature of a corresponding surface of finished products of the finely ground products. 
     
     
         6 . A method for processing a plurality of lens blanks into finely ground products by using the processing device of  claim 1 , said method comprising:
 (a) inversely deducing requirements for the lens center thickness and curvature radius of the finely ground products based on the requirements for finished lens products for the lens center thickness and curvature radius, designing said two processing fixtures based on the requirements of the finished lens products for the center thickness and curvature radius of the finished lens products, wherein the lens center thickness and curvature radius comprise surface dimensional parameters comprising the curvature of the arc surface of said two processing fixtures, the size of the three grooves of each said processing fixtures and the arrangement of the three grooves of each said processing fixtures;   (b) disposing a resistance cloth in each said groove of said first of said two processing fixtures, wherein the curvature radius of the arc surface of the fixture body of said first of said two processing fixtures plus the thickness of the resistance cloth is equal to the curvature radius of a corresponding surface of a lens fine grinding product, the inner diameter of the groove is the sum of the diameter of the lens and the thicknesses of an annular ring, the three grooves of each said processing fixture are evenly distributed on the arc surface of each said processing fixture and the included angles between the center lines of the three grooves of each said processing fixture and the center line of the fixture body of each said processing fixture are equal;   (c) performing a first surface processing act on the lens blank and placing the three lens blanks in the three grooves of said first of said two processing fixtures, pressing said first of said two processing fixtures on the fine grinding mold by the pressure head of the center-of-ball machine, adjusting the curvature of the arc-shaped working surface of the fine grinding mold based on the curvature requirements of the corresponding surface of the fine grinding products and passively rotating said first of said two processing fixtures at high speed under the fine grinding mold to process one surface of the lens blanks to yield semi-finished products; and   (d) placing the semi-finished products in said three grooves of said second of said two processing fixtures, pressing said second of said two processing fixtures on the fine grinding mold by the pressure head of the center-of-ball machine, adjusting the curvature of the arc working surface of the fine grinding mold based on the curvature requirements of the corresponding surface of the fine grinding product and passively rotating said second of said two processing fixtures at high speed under the find grinding mold to process the semi-finished products to yield finished products.   
     
     
         7 . The method according to  claim 6 , wherein in step (c) and step (d), the pressure on the processing fixture is 0.5-10 kg and the speed of the fine grinding mold is 800˜3500 rpm. 
     
     
         8 . The method according to  claim 6 , wherein in step (c) and step (d), the ratio of the diameter of the fine grinding mold to the diameter of one of said processing fixtures is 1.5:1. 
     
     
         9 . The method according to  claim 6 , wherein in step (c) and step (d), the curvature of the arc working surface in the fine grinding mold is based on the curvature of the corresponding surface of the finished products and upon processing 3˜5 s with the fine grinding mold corresponding to the curvature of the arc working surface, said processing is stopped, the plurality of semi-finished products are taken out to be measured for the curvature of the processed surfaces, wherein said plurality of semi-finished products are processed until the curvatures of the plurality of semi-finished products meet the curvatures of the finished products. 
     
     
         10 . The method according to  claim 6 , wherein in step (c) and step (d), the curvature of the arc working surface in the fine grinding mold is based on the curvature of the corresponding surface of the finished products and upon processing 3˜5 s with the fine grinding mold corresponding to the curvature of the arc working surface, said processing is stopped, the plurality of lens blanks are taken out to be measured for the curvature of the processed surfaces, wherein said plurality of lens blanks are processed until the curvatures of the plurality of lens blanks meet the curvatures of the finished products.