Suspension for disc drive and manufacturing method therefor

Abstract

A suspension for disc drive comprises a base plate, a load beam attached to the base plate, and a flexure attached to the load beam. The load beam includes a rigid body portion, formed of a thick plate independent of the base plate, and a spring portion, formed of a spring member in the form of a thin sheet independent of the rigid body portion. The spring member connects the rigid body portion and the base plate. The spring member is thinner than the rigid body portion and has a lower spring constant. The spring portion is more flexible than the rigid body portion.

What is claimed is:  
     
         1 . A suspension for disc drive, comprising: 
 a base plate;    a load beam attached to the base plate; and    a flexure attached to the load beam and adapted to be fitted with a head portion,    the load beam including: a rigid body portion which is formed as a separate member from the base plate and to which the flexure is fixed; and a spring portion formed of a spring member which connects the rigid body portion and the base plate together and which has a spring constant lower than that of the body portion.    
     
     
         2 . A suspension for disc drive according to    claim 1   , wherein said rigid body portion of said load beam is formed of a light metal or synthetic resin.  
     
     
         3 . A suspension for disc drive according to    claim 1   , wherein said load beam is a laminated member that is made up of at least two kinds of materials including a light metal.  
     
     
         4 . A suspension for disc drive according to    claim 3   , wherein said load beam is a laminated member that is made up of an aluminum-based metal plate and a stainless steel plate.  
     
     
         5 . A suspension for disc drive according to    claim 1   , wherein said load beam is a laminated member that is made up of an aluminum-based metal plate and a stainless steel plate, said base plate is a laminated member that is made up of an aluminum-based metal plate and a stainless steel plate, and said spring member is formed of stainless steel and laser-welded to both the stainless steel plate of the load beam and the stainless steel plate of the base plate.  
     
     
         6 . A suspension for disc drive according to    claim 1   , wherein said base plate is an arm-type long base plate and is made as a laminated member that is made up of at least two kinds of materials including a light metal.  
     
     
         7 . A suspension for disc drive according to    claim 1   , wherein said flexure and said spring portion are formed of one integral sheet.  
     
     
         8 . A method for manufacturing a suspension for disc drive, comprising: 
 a process for manufacturing a semi-finished suspension product integrally including a base plate, a rigid body portion of a load beam, and a pair of connecting portions connecting the base plate and the rigid body portion;    a process for fixing a spring member, formed independently of the semi-finished suspension product, to the base plate and the rigid body portion of the semi-finished product; and    a process for cutting off the connecting portions, projecting individually from the opposite sides of the spring member, from the base plate and the rigid body portion after the spring member is fixed to the semi-finished suspension product.    
     
     
         9 . A method for manufacturing a suspension according to    claim 8   , wherein the distance between said pair of connecting portions is greater than the width of the spring member.