Pneumatic grinder

Abstract

The present invention provides a pneumatic grinder connected to a driving gear or spindle at the tip end of the coupling shaft, in which a bearing is set upon the front portion for anti-eccentric-shaking, improving the concentricity of the grinder, in order to suit higher running speed smoothly and higher gearing accuracy; the coupling mechanism of the tilting head and the main body is simplified into a single component—retaining cover having two counter revolving oriental threads for securing, meanwhile the sizes of said main body and the driving gear are shortcut; the rotor and the shoots on it are formed in a single process in the injection casting simultaneously, in order to improve manufacturing speed and reduce cost.

I claim:  
     
         1 . A pneumatic grinder, comprised of a main body housing a pneumatic motor at the inside from the front end, by fitting the locating shaft of the rotor into the back bearing at the inside of the main body, and a space ring put on the coupling shaft at the front end of said rotor, and a front cover holding said space ring at the inside, and the retaining cover securing on the front tip end of said main body; wherein, said retaining cover has an inner housing for holding said front cover in and pushing and locating said pneumatic motor in place, the coupling shaft has a thread portion built on the tip end for securing the driving gear, which is located at the inside of said front bearing with the small end for clamping and locating the bearing, said front bearing is located the inside of the tilting head with the outer surface for keeping the concentricity with said coupling shaft, and said tilting head is secured on the inner threaded hole of said retaining cover with the outer thread portion, thereby as screwing said retaining cover into the main body to retain the front cover, simultaneously to fasten the tilting head and to gear the driving gear to the spindle gear located on the spindle for driving the spindle in high speed simultaneous spinning.  
     
     
         2 . A pneumatic grinder as claimed in  claim 1 , wherein said main body has a shaft tube with a bearing housing at the back end for holding in a bearing in.  
     
     
         3 . A pneumatic grinder as claimed in  claim 1 , wherein said retaining cover has an inner thread at the inside hole and an outer thread at the external surface, the said both threads have different revolving orient each other.  
     
     
         4 . A pneumatic grinder as claimed in  claim 1 , wherein, the main body has an external thread built on the outer terminal end, the retaining cover has two counter revolving oriental inner threads for securing on the external threads of said main body and said tilting head to get locking function as above-mentioned structure in  claim 3 .  
     
     
         5 . A pneumatic grinder as claimed in  claim 1 , wherein, said rotor including shoots is shaped by molding in injection casting directly.  
     
     
         6 . A pneumatic grinder as claimed in  claim 1 , wherein, the forcing slots on the surface of said rotor are molded in injection casting directly.  
     
     
         7 . A pneumatic grinder as claimed in  claim 1 , wherein, the coupling shaft, the space ring, and the locating shaft of said rotor can be obtained by turning in a whole piece, the segment between the space ring and the locating shaft may be cut into polygon bar, the shoot shaft and shoots are obtained by molding in injection casting directly.  
     
     
         8 . A pneumatic grinder as claimed in  claim 1 , wherein, said rotor including the shoot shaft and shoots is molded in plastic injection mold.  
     
     
         9 . A pneumatic grinder as claimed in  claim 7 , wherein, said rotor including the shoot shaft and shoots is molded in plastic injection mold.