Cylinder structure

Abstract

A cylinder structure including a plastic cylinder, a metal cylinder, and a metal layer is provided. The plastic cylinder has a first flat on the top thereof. The metal cylinder has a second flat on the top thereof, and is partly inserted into the top of the plastic cylinder, wherein the second flat is higher than the first flat relative to the top of the plastic cylinder. The metal layer covers the exposed surface of the plastic cylinder and the exposed surface of the metal cylinder.

1 . A cylinder structure, comprising:
 a plastic cylinder having a first flat on the top thereof;   a metal cylinder partly inserted into the top of the plastic cylinder, and having a second flat on the top of the metal cylinder, wherein the second flat is higher than the first flat relative to the top of the plastic cylinder; and   a metal layer covering the exposed surface of the plastic cylinder and the exposed surface of the metal cylinder.   
   
   
       2 . The cylinder structure according to  claim 1 , wherein the plastic cylinder has a first hole having a first shoulder on the inner surface of the first hole, and the metal cylinder has a second shoulder supported by the first shoulder. 
   
   
       3 . The cylinder structure according to  claim 2 , wherein the metal cylinder has a second hole having an internal thread on the inner surface of the second hole. 
   
   
       4 . The cylinder structure according to  claim 2 , wherein the metal cylinder has a first segment and a second segment, and the joint between the first segment and the second segment forms the second shoulder. 
   
   
       5 . The cylinder structure according to  claim 4 , wherein a part of the first segment protrudes from the first flat, and the part of the first segment has the second flat, and the first segment has a plurality of concaves spread on the outer surface thereof. 
   
   
       6 . The cylinder structure according to  claim 1 , wherein the plastic cylinder has a burr formed on the outermost edge of the first flat. 
   
   
       7 . The cylinder structure according to  claim 1 , wherein the plastic cylinder has a plurality of reinforcing ribs distributed on the outer side of the plastic cylinder. 
   
   
       8 . An electronic device housing, comprising:
 a wall;   at least one plastic cylinder, having a first flat on the top thereof, and the bottom of the plastic cylinder attached to an inner surface of the wall;   at least one metal cylinder, partly inserted into the top of the plastic cylinder, and having a second flat on the top of the metal cylinder, wherein the second flat is higher than the first flat relative to the top of the plastic cylinder; and   a metal layer, covering the exposed portion of the inner surface of the wall, the exposed surface of the plastic cylinder, and the exposed surface of the metal cylinder.   
   
   
       9 . The electronic device housing according to  claim 8 , wherein the plastic cylinder has a first hole having a first shoulder on the inner surface of the first hole, and the metal cylinder has a second shoulder supported by the first shoulder. 
   
   
       10 . The electronic device housing according to  claim 9 , wherein the metal cylinder has a second hole having internal thread on the inner surface of the second hole. 
   
   
       11 . The electronic device housing according to  claim 9 , wherein the metal cylinder has a first segment and a second segment, and the joint between the first segment and the second segment forms the second shoulder. 
   
   
       12 . The electronic device housing according to  claim 11 , wherein a part of the first segment protrudes from the first flat, and the part of the first segment has the second flat, and the outer surface of the first segment has a plurality of concaves spread on the outer surface thereof. 
   
   
       13 . The electronic device housing according to  claim 8 , wherein the plastic cylinder has a burr formed on the outermost edge of the first flat. 
   
   
       14 . The electronic device housing according to  claim 8 , wherein the plastic cylinder has a plurality of reinforcing ribs distributed on the outer side of the plastic cylinder. 
   
   
       15 . The electronic device housing according to  claim 8 , wherein the wall and the plastic cylinder are integrally formed.