Method for manufacturing a rail for use in a linear motion rolling contact guide unit

Abstract

A method for manufacturing a rail for use in a linear motion rolling contact guide unit is provided. A rail intermediate product having a top surface, a pair of side surfaces, each formed with a guide groove portion, and a bottom surface is provided by drawing from an alloy steel material. Then the guide groove portion is hardened by induction hardening. The side surface is then ground by a profiled grinder having a grinding shape complementary to the shape of a side surface of a finished rail.

What is claimed is: 
     
       1. A method for manufacturing a rail for use in a linear motion rolling contact guide unit, comprising the steps of: providing a rail intermediate product having a top surface, a pair of side surfaces and a bottom surface by drawing a metal material, such that each of said side surfaces is formed with a guide groove portion extending in parallel with a longitudinal axis of said rail intermediate product;   first hardening said guide groove portion; and   then grinding each of said side surfaces in its entirety using a profiled grinder having a grinding shape complementary to a shape of a finished side surface of said rail, which includes a tapered relief trench at a bottom thereof.   
     
     
       2. The method of claim 1, wherein said side surface of said rail also includes a side recess separated away from said guide groove. 
     
     
       3. The method of claim 1, wherein each of said side surfaces of said rail intermediate product is formed with a relief trench portion when drawn. 
     
     
       4. The method of claim 1, wherein said hardening step is carried out by an induction hardening process.