Grinding device using ultrasonic vibration

Abstract

A grinding device ( 30 ) for grinding an object ( 31 ) at high accuracy has a support table ( 32 ) on which the object ( 31 ) is supported and fixed, a vertically movable rotating shaft ( 34 ) arranged above the support table, a drive device ( 35 ) for vertically moving the rotating shaft, a drive device ( 36 ) for rotating the rotating shaft, an elastic body ( 37 ) fixed to a base section of the rotating shaft, an annular grind stone ( 38 ) provided to a bottom of the elastic body, ultrasonic vibrators ( 39 ) arranged on the elastic body, and a transmission unit ( 41 ) for transmitting electric energy to the ultrasonic vibrators, in which the elastic body is an annular elastic body and a connection plate ( 42 ) is provided between the annular elastic body and the base section of the rotating shaft under such condition that the connection plate and the annular elastic body are connected by connection means ( 45 ) having alternately arranged connection sections and space sections and each ultrasonic vibrator is arranged at a predetermined position of the elastic body.

1 . A grinding machine comprising a support table on which an object to be ground is supported and fixed, a vertically movable rotating shaft arranged above the support table, a drive device for vertically moving the rotating shaft, a drive device for rotating the rotating shaft, an elastic body fixed to a base section of the rotating shaft, an annular grind stone provided to a bottom of the elastic body, ultrasonic vibrators arranged on the elastic body, and a transmission unit for transmitting electric energy to the ultrasonic vibrators, wherein
 the elastic body is an annular elastic body, a connection plate having connection means comprising alternately formed connection sections and space sections on a bottom surface thereof is provided between the annular elastic body and the base section of the rotating shaft under the condition that the connection sections are bonded to a top surface of the annular elastic body, and the ultrasonic vibrators are placed on the top surface of the annular elastic body in an area facing the space sections or on an inner or outer side surface of the annular elastic body in a area adjacent to the area facing the space sections, or   the elastic body is an annular elastic body, a connection plate having connection means comprising alternately formed connection sections and space sections on an outer side surface thereof is provided between the annular elastic body and the base section of the rotating shaft under the condition that the connection sections are bonded to an inner side surface of the annular elastic body, and the ultrasonic vibrators are placed on the inner side surface of the annular elastic body in an area facing the space sections or on a top surface or an outer side surface of the annular elastic body in a area adjacent to the area facing the space sections.   
   
   
       2 . The grinding machine of  claim 1 , in which the connection plate and connection sections are made of elastic material. 
   
   
       3 . The grinding machine of  claim 1 , in which the connection plate and connection sections are made of elastic material, and the connection plate, connection sections and annular elastic body are formed as a single unit. 
   
   
       4 . The grinding machine of  claim 1 , in which a ratio of a length of the connection section and a length of the space section is in the range of 1:1 to 1:20, the length being determined along a periphery of the connection plate. 
   
   
       5 . The grinding machine of  claim 1 , in which the transmission unit for transmitting electric energy to the ultrasonic vibrators is a rotary transformer. 
   
   
       6 . The grinding machine of  claim 1 , in which the connection sections are arranged symmetrically around the rotating shaft and the space sections of the connection means are arranged symmetrically around the rotating shaft. 
   
   
       7 . The grinding machine of  claim 1 , in which the ultrasonic vibrators are arranged symmetrically around the rotating shaft. 
   
   
       8 . The grinding machine of  claim 1 , in which the support table is rotatable, and the rotatable support table is equipped with a drive unit driving the support table.