Grinder

Abstract

A grinder may include a spindle, a grinding wheel and a mount disk. The spindle may be configured to generate a rotary force. The grinding wheel may be configured to receive the rotary force from the spindle and grind an object. The mount disk may be between the spindle and the grinding wheel and may be configured automatically engage or disengage the grinding wheel based on a rotation direction of the mount disk. Thus, an exchange or replacement of the grinding wheel may be performed in a short time by rotating the spindle so that the grinding wheel is disengaged from the mount disk.

What is claimed is: 
     
         1 . A grinder comprising:
 a spindle configured to generate a rotary force;   a grinding wheel configured to receive the rotary force from the spindle and grind an object based on the rotary force; and   a mount disk arranged between the spindle and the grinding wheel, the mount disk configured to automatically engage or disengage the grinding wheel based on a rotation direction of the mount disk.   
     
     
         2 . The grinder of  claim 1 , wherein the mount disk comprises:
 an inner disk connected to the spindle;   an outer disk connected to the inner disk; and   a plurality of combination shafts configured to engage or disengage the grinding wheel based on a rotation direction of the outer disk.   
     
     
         3 . The grinder of  claim 2 , wherein the outer disk comprises:
 an inner race connected to the inner disk, the inner race including a plurality of first gear teeth on a circumferential surface of the inner race; and   an outer race spaced apart from the inner race, the outer race and inner race defining a receiving space, the outer race including a plurality of second gear teeth on a circumferential surface of the outer race.   
     
     
         4 . The grinder of  claim 3 , wherein each combination shaft of the plurality of combination shafts comprises:
 a geared portion configured to engage the plurality of first gear teeth of the inner race and the plurality of second gear teeth of the outer race; and   a screwed portion extended from the geared portion and configured to engage or disengage the grinding wheel based on a rotation direction of the geared portion.   
     
     
         5 . The grinder of  claim 4 , wherein the screwed portion has a diameter smaller than a diameter of the geared portion. 
     
     
         6 . The grinder of  claim 4 , wherein the receiving space comprises:
 a receiving groove configured to receive the geared portion; and   at least one screwed hole extended from the receiving groove and configured to receive the screwed portion, the screwed hole including at least one groove configured to threadedly engage the screwed portion.   
     
     
         7 . The grinder of  claim 6 , wherein the plurality of first gear teeth and the plurality of second gear teeth define sidewalls of the receiving space. 
     
     
         8 . The grinder of  claim 6 , wherein the screwed hole has a diameter smaller than a diameter of the receiving space. 
     
     
         9 . The grinder of  claim 6 , further comprising:
 a seal arranged between an inner circumferential surface of the screwed hole and the screwed portion.   
     
     
         10 . The grinder of  claim 1 , further comprising:
 an actuator connected to the spindle, the actuator configured to generate the rotary force.   
     
     
         11 . The grinder of  claim 1 , wherein the object comprises a semiconductor wafer. 
     
     
         12 . A grinder comprising:
 a spindle configured to generate a rotary force;   a grinding wheel configured to receive the rotary force from the spindle and grind a surface of a semiconductor wafer based on the rotary force;   an inner disk connected to the spindle;   an outer disk connected to the inner disk; and   a plurality of combination shafts configured to engage or disengage the grinding wheel based on a rotation direction of the outer disk.   
     
     
         13 . The grinder of  claim 12 , wherein the outer disk comprises:
 an inner race connected to the inner disk, the inner race including an inner gear surface; and   an outer race spaced apart from the inner race, the outer race and the inner race defining a receiving space, the outer race including an outer gear surface.   
     
     
         14 . The grinder of  claim 13 , wherein each combination shaft of the combination shafts comprises:
 a geared portion configured to engage with the inner gear surface and the outer gear surface; and   a screwed portion extended from the geared portion and configured to engage or disengage the grinding wheel based on a rotation direction of the geared portion.   
     
     
         15 . The grinder of  claim 14 , wherein the screwed portion has a diameter smaller than a diameter of the geared portion. 
     
     
         16 . The grinder of  claim 14 , wherein the receiving space comprises:
 a receiving groove configured to receive the geared portion; and   at least one screwed hole extended from the receiving groove and configured to receive the screwed portion, the screwed hole including at least one groove configured to threadedly engage the screwed portion.   
     
     
         17 . The grinder of  claim 16 , wherein the inner gear surface and the outer gear surface define sidewalls of the receiving space. 
     
     
         18 . The grinder of  claim 16 , further comprising:
 a seal arranged between an inner circumferential surface of the screwed hole and the screwed portion.   
     
     
         19 . A grinder comprising:
 an actuator configured to generate a rotary force.   a spindle configured to rotate based on the rotary force;   a grinding wheel configured to receive the rotary force from the spindle and grind a surface of a semiconductor wafer based on the rotary force;   an inner disk connected to the spindle;   an outer disk connected to the inner disk; and   a plurality of combination shafts configured to engage or disengage the grinding wheel based on rotation directions of the outer disk;   the outer disk including,
 an inner race connected to the inner disk, the inner race including an inner gear surface, and 
 an outer race spaced apart from the inner race, the outer race and the inner race defining a receiving space, the outer race including an outer gear surface; and 
   each combination shaft of the plurality of combination shafts including,
 a geared portion configured to engage with the inner gear surface and the outer gear surface; and 
 a screwed portion extended from the geared portion and configured to engage or disengage the grinding wheel based on a rotation direction of the geared portion. 
   
     
     
         20 . The grinder of  claim 19 , further comprising:
 a seal arranged between an inner circumferential surface of a screwed hole included in the receiving space and the screwed portion.