Magnetic recording and reproducing apparatus capable of preventing deterioration of transmission characteristic

#1. Field of the Invention

#The present invention relates to a magnetic recording and reproducing apparatus and specifically, to a flexible substrate structure for transmission and reception of signals, used in a rotating head unit for broadband storage such as a video tape recorder (VTR) and the like.

#2. Description of the Related Art

#The above objects, other objects, features and advantages of the present invention will be better understood from the following description taken in conjunction with the accompanying drawings, in which:

#FIG. 1 is a plan view of rotary transformer to which a flexible substrate according to a first embodiment of the present invention is connected;

#FIG. 2 is a plan view showing a state where the flexible substrate of the present invention is further developed;

#Now, a first embodiment of the present invention will be explained with reference to FIG. 1 through FIG. 7. FIG. 1 is a plan view of rotary transformer to which a flexible substrate according to a first embodiment of the present invention is connected; FIG. 2 is a plan view showing a state where the flexible substrate of the present invention is further developed; FIG. 3 is a plan view showing signal lines and shield layer of the flexible substrate of the present invention; FIG. 4 is a simple explanatory diagram showing an arrangement of the signal lines and the shield layer according to the present invention; FIG. 5 is a simple explanatory diagram showing an arrangement of a pair of balanced signal lines connected to the input terminals of an operational amplifier according to the present invention; FIG. 6 is a simple explanatory diagram showing another arrangement of a pair of balanced signal lines connected to the input terminals of the operational amplifier according to the present invention; and FIG. 7 is a simple circuit diagram showing the relationship between outside electromagnetic interference noise and the output side of the operational amplifier according to the present invention.

#In the drawings, a flexible substrate 1 is made of resin such as polyimide and the like, in form of a film, and comprises a flexible electrically insulating signal substrate la in which a plurality of signal lines 2 and grand lines 3 made of conductive metal material such as a copper foil and the like are formed on a surface thereof and a flexible shield substrate 1b having a shield layer 4 formed with a plurality of openings 4a thereon.

#At one end of the flexible signal substrate 1a, terminals 5 formed parallel to each other are derived from the plurality of signal lines 2 and grand lines 3 and at the same time, are connected to a connector or a substrate of amplifier and the like (not shown). At the opposite end of the flexible signal structure a plurality of connecting pads 7, derived from the plurality of signal lines 2, are connected through connecting lines 6a to coils (not shown) at the fixed side of a rotary transformer 6 for transmission and reception of signals from and to a rotating magnetic head (not shown).