Wiring board unit for disk devices, actuator assembly for disk devices and disk device comprising the same

Abstract

According to one embodiment, a wiring board unit includes a reinforcing board, a flexible printed circuit board includes a joint portion including a first plane and a second plane and attached on the reinforcing board, a relay unit extending from the first plane, a plurality of connection pad groups located on one of the first plane and the second plane and a first IC chip mounted on the first plane, and the joint portion is bent on a boundary between the first plane and the second plane.

What is claimed is: 
     
         1 . A wiring board unit comprising:
 a board;   a flexible printed circuit board comprising a joint portion attached on the board, the joint portion comprising a first plane and a second plane, a relay unit extending from the first plane, and a plurality of connection pad groups located on one of the first plane and the second plane; and   a first IC chip mounted on the first plane, wherein   the joint portion being bent on a boundary between the first plane and the second plane.   
     
     
         2 . The wiring board unit of  claim 1 , further comprising:
 a second IC chip mounted on the second plane,   wherein   the relay unit extending from the joint portion in a direction along the boundary, and   the connection pad groups are located on an opposite side to the relay unit and provided on the first plane.   
     
     
         3 . The wiring board unit of  claim 1 , further comprising:
 a second IC chip mounted on the second plane,   wherein   the relay unit extending in a direction which intersects the boundary, and   the connection pad groups are located between the first IC chip and the boundary in the first plane.   
     
     
         4 . The wiring board unit of  claim 1 , wherein
 the relay unit extends from the joint portion in a direction along the boundary, and   the connection pad groups are located in the second plane.   
     
     
         5 . The wiring board unit of  claim 1 , wherein
 the second plane is folded back along the boundary and overlaid on the first plane, and   the board of a single layer is located between the first plane and the second plane.   
     
     
         6 . The wiring board unit of  claim 1 , wherein
 the second plane is folded back along the boundary and overlaid on the first plane, and   the board comprising two layers is located between the first plane and the second plane.   
     
     
         7 . An actuator assembly comprising:
 a head actuator comprising an actuator block comprising a first surface, and a plurality of suspension assemblies each extending from the actuator block and supporting a magnetic head, and   a wiring board unit being connected to the head actuator and comprising a board, a flexible printed circuit board comprising a joint portion provided on the board, the joint portion comprising a first plane and a second plane, a relay unit extending from the first plane, a plurality of connection pad groups located on one of the first plane and the second plane, and a first IC chip mounted on the first plane,   the joint portion being bent on a boundary between the first plane and the second plane.   
     
     
         8 . The actuator assembly of  claim 7 , wherein
 the actuator block comprises a trench portion in the first surface,   the wiring board unit comprises a second IC chip mounted on the second plane,   the second plane with the second IC chip is in contact with the first surface, and   the second IC chip is accommodated inside the trench portion.   
     
     
         9 . The actuator assembly of  claim 8 , wherein
 the relay unit extends from the joint portion in a direction along the boundary, and   the connection pad groups are located on an opposite side to the relay unit on the first plane.   
     
     
         10 . The actuator assembly of  claim 8 , wherein
 the relay unit extends from the joint portion in a direction which intersects the boundary, and   the connection pad groups are located between the boundary and the first IC chip on the first plane.   
     
     
         11 . The actuator assembly of  claim 7 , wherein
 the relay unit extends from the joint portion in a direction along the boundary, and   the connection pad groups are located in the second plane.   
     
     
         12 . The actuator assembly of  claim 7 , wherein
 the second plane is folded back along the boundary and overlaid on the first plane, and   the board of a single layer is located between the first plane and the second plane.   
     
     
         13 . The actuator assembly of  claim 7 , wherein
 the second plane is folded back along the boundary, and overlaid on the first plane, and   the board comprising two layers is located between the first plane and the second plane.   
     
     
         14 . The actuator assembly of  claim 7 , further comprising:
 a second IC chip mounted on the second plane,   wherein   the actuator block comprises an end surface extending to intersect the first surface,   the first plane is placed on the first surface via the board, and   the second surface is placed on the end surface via the board.   
     
     
         15 . A disk device comprising:
 a disk-shaped recording medium comprising a record layer; and   the actuator assembly of  claim 7 .   
     
     
         16 . A wiring board unit comprising:
 a board;   a flexible printed circuit board comprising a joint portion attached on the board, the joint portion comprising a first plane and a second plane, a relay unit extending from the first plane, a plurality of connection pad groups located on one of the first plane and the second plane; and   a first IC chip mounted on the first plane.