Electromagnetic device, high-voltage generating device, and method for making the electromagnetic device

Abstract

An electromagnetic device and a high-voltage generating device which are thin and improved in the characteristics are provided in which a magnetic core 3 is made of a cylindrical form of a ferrite material having a higher intrinsic resistance. A winding is provided by winding a flat rectangular wire conductor 2 in an edge-wise winding form directly on substantially the entire length of the magnetic core 3 . As any insulator such as a coil bobbin is not needed between the flat rectangular wire conductor 2 and the magnetic core 3 , the winding can be decreased in the overall size or thickness thus contributing to the dimensional reduction of the electromagnetic device. Also, as its flat rectangular wire conductor 2 is wound directly on the magnetic core 3 , the winding can be minimized in the length and thus the overall resistance. Moreover, as there is no gap between the winding and the magnetic core 3 , the self-inductance can be reduced while the size and the number of turns of the winding remain unchanged.

1 . An electromagnetic device comprising a magnetic core having a curved side and a flat rectangular wire conductor wound in an edge-wise winding form directly on the curved side of the magnetic core, the magnetic core having an intrinsic resistance of not smaller than 1000 Ω●m.  
     
     
         2 . The electromagnetic device according to  claim 1 , further comprising a winding provided on the outer surface of the flat rectangular wire conductor.  
     
     
         3 . The electromagnetic device according to  claim 1 , wherein the magnetic core includes a rough finished surface.  
     
     
         4 . The electromagnetic device according to  claim 2 , wherein the flat rectangular wire conductor and the winding are joined to each other by fusing their coatings.  
     
     
         5 . The electromagnetic device according to  claim 2 , wherein the magnetic core of an edge-wise winding form of the flat rectangular wire conductor is located between a group of leads joined together.  
     
     
         6 . The electromagnetic device according to  claim 2 , further comprising a first insulating member of a cylindrical shape to which the magnetic core of the flat rectangular wire conductor is fitted and a secondary insulating material covering the first insulating member and the winding which is made of an electrically conductive resin material and provided on the outer side of the first insulating member.  
     
     
         7 . The electromagnetic device according to  claim 6 , wherein the first insulating member has a groove provided in the outer side thereof and the winding is fabricated by filling the groove with an electrically conductive resin material.  
     
     
         8 . The electromagnetic device according to  claim 2 , wherein the flat rectangular wire conductor serves as a secondary winding and the winding serves as a primary winding.  
     
     
         9 . The electromagnetic device of  claim 1  having a transformer arrangement in which the core includes a bar-like magnetic core and the flat rectangular wire conductor wound on the outer surface of the magnetic core is for generation of a high voltage, the flat rectangular wire conductor being drawn out at both ends from two ends of the magnetic core respectively, wherein a resin outer housing is provided about the transformer by one of filling and molding an insulating resin material and having at least one side thereof configured along a direction substantially parallel with the axial direction of the magnetic core.  
     
     
         10 . The electromagnetic device of  claim 1  having a transformer arrangement which includes the magnetic core, a winding and the flat rectangular wire conductor both provided on the magnetic core, and at least two terminals for connection of the winding and the flat rectangular wire conductor with the outside, wherein the transformer is sealed in an injection molded form of a thermoset resin material.  
     
     
         11 . The electromagnetic device according to  claim 10 , wherein the thermoset resin material is covered with a molded form of a thermoplastic resin material.  
     
     
         12 . The electromagnetic device according to  claim 10 , wherein the winding and the flat rectangular wire conductor are secured, at least at one end with an adhesive, to a side of the magnetic core.  
     
     
         13 . The electromagnetic device according to  claim 10 , wherein while the winding acts as a primary winding, the flat rectangular wire conductor acts as a secondary winding and is insulated by coating and provided in an edge-wise winding form on the magnetic core.  
     
     
         14 . A method for making the electromagnetic device of  claim 1  comprising: 
 winding the flat rectangular wire conductor in the edge-wise winding form on the magnetic core; and    fixedly joining ends of the flat rectangular wire conductor provided in the edge-wise winding form to corresponding terminals that are provided integrally on a single metal strip.    
     
     
         15 . The method for making an electromagnetic device according to  claim 14 , wherein the metal strip is arranged of a linear form to which the ends of the flat rectangular wire conductor are joined as drawn out in one direction towards the metal strip.