Method of fabricating an electroacoustic transducer

Abstract

The present invention provides a fabrication method of an electroacoustic transducer capable of simplifying an assembling process on a lead frame and realizing an automatic assembly. The method comprises steps of forming pole piece portions, forming a lead frame having a plurality of base forming areas thereon, each of the areas having lead terminals formed therein, forming bases of a synthetic resin on the lead frame by molding so that the pole piece portions are embedded in the bases, mounting a coil on the pole piece portions embedded in the bases, disposing a support ring and a magnet so as to surround the coil, and placing a diaphragm on the support ring to be held thereby, connecting opposite ends of the coil to the lead terminals, cutting off the lead terminals from the lead frame, putting cases on and fixedly joining the same to the bases, and subjecting the cut lead terminals to a forming process.

What is claimed is: 
     
       1. A method of fabricating an electroacoustic transducer for converting electric input signals into sound, said method comprising steps of: forming pole piece portions;   forming a lead frame having a plurality of base forming areas thereon, each of said areas having lead terminals formed therein;   forming bases of a synthetic resin on said lead frame by molding so that said pole piece portions are embedded in said bases;   mounting a coil on each of said pole piece portions embedded in said bases, surrounding said coil with support ring and magnet sections, and placing a diaphragm on said support ring section to be held thereby;   connecting opposite ends of said coil to said lead terminals;   cutting off said lead terminals from said lead frame;   putting cases on and fixedly joining the same to said bases; and   subjecting said cut lead terminals to a forming process.   
     
     
       2. A method of fabricating an electroacoustic transducer for converting electric input signals into sound, said method comprising steps of: forming pole piece portions;   forming a lead frame having a plurality of base forming areas thereon, each of said areas having lead terminals formed therein;   forming bases of a synthetic resin on said lead frame by molding so that said pole piece portions are embedded in said bases;   mounting a coil on each of said pole piece portions embedded in said bases, surrounding said coil with support ring and magnet sections, and placing a diaphragm on said support ring section to be held thereby;   connecting opposite ends of said coil to said lead terminals;   putting cases on and fixedly joining the same to said bases, said putting being carried out on said lead frame;   cutting off said lead terminals from said lead frame; and   subjecting said cut lead terminals to a forming process.   
     
     
       3. A method of fabricating an electroacoustic transducer according to claim 1 or 2, wherein said coil is formed by winding a wire as an individual air-core coil or by directly winding a wire around a core of one of said pole piece portions embedded in said bases on said lead frame. 
     
     
       4. A method of fabricating an electroacoustic transducer according to claim 1 or 2, wherein said support ring and magnet sections are integrally formed from a single magnetic member. 
     
     
       5. A method of fabricating an electroacoustic transducer according to claim 1 or 2, wherein said support ring and magnet sections are separate units. .Iadd. 
     
     
       6.  A method of fabricating an electroacoustic transducer comprising the steps of: forming pole piece portions;   forming a lead frame having a plurality of base forming areas thereon, each of said areas having lead terminals formed therein;   forming bases of a synthetic resin on said lead frame so that said lead terminals and pole piece portions are embedded in said bases;   mounting a coil on each of said pole piece portions embedded in said bases;   disposing a diaphragm with a given interval between itself and said pole piece portions;   connecting opposite ends of said coil to said lead terminals; and   cutting off said lead terminals from said lead frame. .Iaddend..Iadd.   
     
     
       7.  A method of fabricating an electroacoustic transducer comprising the steps of: forming pole piece portions;   forming a lead frame having a plurality of base forming areas thereon, each of said areas having lead terminals formed therein;   forming bases of a synthetic resin on said lead frame so that said lead terminals and pole piece portions are embedded in said bases;   mounting a coil on each of said pole piece portions embedded in said bases;   disposing a diaphragm with a given interval between itself and said pole piece portions;   connecting opposite ends of said coil to said lead terminals;   putting cases on said bases formed on said lead frame; and   cutting off said lead terminals from said lead frame. .Iaddend..Iadd.8. A method of fabricating an electroacoustic transducer according to claim 6, wherein said mounting of a coil is performed by mounting a wound coil or directly winding a wire around each of said pole piece portions on said lead frame. .Iaddend..Iadd.9. A method of fabricating an electroacoustic transducer according to claim 7, wherein said mounting of a coil is performed by mounting a wound coil or directly winding a wire around each of said pole piece portions on said lead frame. .Iaddend..Iadd.10. A method of fabricating an electroacoustic transducer according to claim 6, wherein a magnet is disposed around the periphery of the coil and the   
     
     
        magnet supports the diaphragm. .Iaddend..Iadd.11.  A method of fabricating an electroacoustic transducer according to claim 7, wherein a magnet is disposed around the periphery of the coil and the magnet supports the diaphragm. .Iaddend..Iadd.12. A method of fabricating an electroacoustic transducer according to claim 6, wherein a support ring is disposed around the periphery of the coil and the support ring supports the diaphragm. .Iaddend..Iadd.13. A method of fabricating an electroacoustic transducer according to claim 7, wherein a support ring is disposed around the periphery of the coil and the support ring supports the diaphragm. .Iaddend.