Structure for Casehardening a Fixture of a Guide Plate of a Chain Saw

Abstract

A structure for casehardening a fixture of a guide plate of a chain saw is disclosed and comprises: a metal member being larger than the guide plate and having a slot, the dimension between the two edges of the slot being a sum of the dimension of the outer figure of the guide plate and the dimension of a tolerance, the tolerance being defined as an allowable electrode discharging distance; and at least one cooling structure being disposed around one of the edges utmostly and only having one inlet and one outlet, other useless opens being sealed by sealing structures.

1 . A structure for casehardening a fixture of a guide plate of a chain saw comprising:
 a metal member being larger than the guide plate and having a slot, the dimension between the two edges of the slot being a sum of the dimension of the outer figure of the guide plate and the dimension of a tolerance, the tolerance being defined as an allowable electrode discharging distance; and   at least one cooling structure being disposed around one of the edges utmostly and only having one inlet and one outlet, other useless opens being sealed by sealing structures.   
   
   
       2 . The structure for casehardening the fixture of the guide plate of the chain saw according to  claim 1 , wherein the cooling structure has a groove close to one of the edges of the slot of the metal member, the groove has the inlet, the outlet and a useless open, which is on the surface of the metal member and sealed and welded by a metal plate. 
   
   
       3 . The structure for casehardening the fixture of the guide plate of the chain saw according to  claim 1 , wherein the cooling structure can be shaped as a long tube with a plurality of holes and connected to other cooling structures, each cooling structure is utmostly disposed around one of the edges of the slot so as to let each cooling structure be adjacent to one of the edges of the slot, each cooling structure only has the inlet and the outlet, other useless opens are all sealed. 
   
   
       4 . The structure for casehardening the fixture of the guide plate of the chain saw according to  claim 1 , wherein the inlet and the outlet are for ice water or lower temperature gas coming in and going out. 
   
   
       5 . The structure for casehardening the fixture of the guide plate of the chain saw according to  claim 1 , wherein the metal member is for high frequency induction operations. 
   
   
       6 . The structure for casehardening the fixture of the guide plate of the chain saw according to  claim 1 , wherein the allowable electrode discharging distance is 0.5 mm.