초록 ▼

A piezoelectric sound generator includes a piezoelectric device consisting of a metal diaphragm and a piezoelectric porcelain plate affixed to the diaphragm, a pair of connecting members having resistors connected to the piezoelectric device in series, a leakage magnetic flux coil connected in paral

A piezoelectric sound generator includes a piezoelectric device consisting of a metal diaphragm and a piezoelectric porcelain plate affixed to the diaphragm, a pair of connecting members having resistors connected to the piezoelectric device in series, a leakage magnetic flux coil connected in parallel to the piezoelectric device and the resistors in series, and a resin case. The resin case encases the piezoelectric device and containing the resistors, and has a spool for retaining the leakage magnetic flux coil. In addition, the resin case embraces a portion of the connecting members. This piezoelectric sound generator is manufactured by the steps of: soldering the resistors to the connecting members; forming the resin case in an insertion mold into which the connecting members have been placed, whereby a portion of the connecting members is embraced by the resin case; and attaching the piezoelectric device and the coil to the resin case. The sound generator thus obtained is so accommodated by a handset having sound emission holes that a cavity is defined by the piezoelectric device, the resin case and the handset.

대표청구항 ▼

1. A piezoelectric sound generator comprising: a piezoelectric device comprising a metal diaphragm and a piezoelectric porcelain plate affixed to said diaphragm, the piezoelectric device having a first electrode and a second electrode; a first resistor having first and second terminals, said fir

1. A piezoelectric sound generator comprising: a piezoelectric device comprising a metal diaphragm and a piezoelectric porcelain plate affixed to said diaphragm, the piezoelectric device having a first electrode and a second electrode; a first resistor having first and second terminals, said first terminal connected in series to the first electrode of said piezoelectric device; a second resistor having first and second terminals, said first terminal connected in series to the second electrode of the piezoelectric device; and a leakage magnetic flux coil connected in parallel to said piezoelectric device and said second terminal of the first resistor and the second resistor, respectively. 2. A sound generator according to claim 1 further comprising connecting members to which said resistors are attached, for connecting said piezoelectric device with said coil. 3. A sound generator according to claim 2 further comprising a resin case including an encasing portion for retaining said piezoelectric device, a containing portion for containing said resistors, and a spool for retaining said coil. 4. A sound generator according to claim 3, wherein a portion of said connecting members is embraced by said resin case. 5. A piezoelectric sound generator comprising: a piezoelectric device including a metal diaphragm and a piezoelectric porcelain plate affixed to said diaphragm, the piezoelectric device having a first electrode and a second electrode; a first resistor having first and second terminals, said first terminal connected in series to the first electrode of the piezoelectric device; a second resistor having first and second terminals, said first terminal connected in series to the second electrode of the piezoelectric device; a leakage magnetic flux coil connected in parallel to said piezoelectric device and said second terminals of the first resistor and the second resistor, respectively; and a resin case including an encasing portion for retaining said piezoelectric device, a containing portion for containing said resistor, and a spool for retaining said coil. 6. A sound generator according to claim 5 further comprising connecting members to which said resistors are attached, for connecting said piezoelectric device with said coil. 7. A sound generator according to claim 6, wherein a portion of said connecting members is embraced by said resin case. 8. A sound generator according to claim 7, wherein said spool is located along the periphery of said resin case. 9. A piezoelectric sound generator which is contained by a handset of a telephone set comprising: a piezoelectric device including a metal diaphragm and a piezoelectric porcelain plate affixed to said diaphragm, the piezoelectric device having a first electrode and a second electrode; a first case containing said piezoelectric device and defining a first cavity with said piezoelectric device; a second case jointed to said first case and defining a second cavity with said handset and said piezoelectric device, a first resistor having first and second terminals, said first terminal connected in series to the first electrode of the piezoelectric device, a second resistor having first and second terminals, said first terminal connected in series to the second electrode of the piezoelectric device, and a leakage magnetic flux coil connected in parallel to the piezoelectric device and said second terminals of the first resistor and the second resistor, respectively. 10. A sound generator according to claim 9, wherein said first case has an encasing portion for retaining said piezoelectric device containing portion for containing said pair of resistors, and a spool for retaining said coil. 11. A sound generator according to claim 10 further comprising connecting members to which said resistors are attached, for connecting said piezoelectric device with said leakage magnetic flux coil. 12. A sound generator according to claim 11, wherein said second case is made of resin and embraces a portion of said connecting members. 13. A sound generator according to claim 12, wherein said spool portion is located along the periphery of said second case. 14. A sound generator according to claim 9, wherein said second case further has a partition wall extending into said second cavity. 15. A sound generator according to claim 14, wherein said partition wall is adjacent said handset at a first gap and adjacent said piezoelectric device at a second gap. 16. A sound generator according to claim 15, in which the volumes of the divisions of said second cavity by said partition wall are in the ratio of 1:1/2-1/4. 17. A piezoelectric sound generator comprising: a piezoelectric device including a first electrode, a second electrode, a metal diaphragm and a piezoelectric porcelain plate affixed to said diaphragm; a leakage magnetic flux coil; connecting bodies to which electronic components are attached, for connecting said piezoelectric device with said coil; a resin case having an encasing portion for retaining said piezoelectric device, a containing portion for containing said electronic components, and a spool portion for retaining said coil, a first resistor having first and second terminals, said first terminal connected in series to the first electrode of the piezoelectric device, a second resistor having first and second terminals, said first terminal connected in series to the second electrode of the piezoelectric device, and the leakage magnetic flux coil being connected in parallel to the piezoelectric device and said second terminals of the first resistor and the second resistor, respectively. 18. A sound generator according to claim 17, wherein a portion of said connecting bodies is embraced by said resin case. 19. A sound generator according to claim 18, wherein said connecting bodies have spring terminals and external connecting terminals. 20. A sound generator according to claim 19, wherein said spring terminals and said external connecting terminals have indentations for retaining said electronic components. 21. A sound generator according to claim 20, wherein said external connecting terminals have standing pins connected with said coil. 22. A piezoelectric receiver comprising: a piezoelectric device including a first electrode, a second electrode, a metal diaphragm and a piezoelectric porcelain affixed to said diaphragm; a support case containing said piezoelectric device so as to define a first cavity with said piezoelectric device; a handset in which sound-emission holes are formed, containing said support case so as to define a second cavity with said piezoelectric device, a first resistor having first and second terminals, said first terminal connected in series to the first electrode of the piezoelectric device, a second resistor having first and second terminals, said first terminal connected in series to the second electrode of the piezoelectric device, and a leakage magnetic flux coil connected in parallel to the piezoelectric device and said second terminals of the first resistor and the second resistor, respectively. 23. A receiver according to claim 22 further comprising connecting members, connected to said piezoelectric device, to which the first and second resistors are attached. 24. A receiver according to claim 22, wherein said support case has an encasing portion for retaining said piezoelectric device, a containing portion for containing said resistors, and a spool for retaining said coil. 25. A receiver according to claim 24 further comprising connecting members to which said resistors are attached, for connecting said piezoelectric device with said coil. 26. A receiver according to claim 25, wherein said support case is made of resin and embraces a portion of said connecting members. 27. A receiver according to claim 26, wherein said connecting members have spring terminals and external connecting terminals. 28. A receiver according to claim 27, wherein said connecting members have indentations into which said resistors are mounted. 29. A receiver according to claim 28, wherein said connecting members have standing pins for connection with said coil. 30. A receiver according to claim 22, wherein said support case also has a partition wall extending into said second cavity. 31. A receiver according to claim 30, wherein said handset has a portion including said sound emission holes, and an cylindrically extending ring formed integrally around said portion including said sound emission holes. 32. A receiver according to claim 31, wherein said partition wall is adjacent said handset at a first gap and adjacent said piezoelectric device at a second gap. 33. A receiver according to claim 32, in which the volumes of the divisions of said second cavity by said partition wall are in the ratio of 1:1/2-1:1/4. 34. A receiver according to claim 33 further comprising a rubber seat provided between said support case and said portion including said sound emission holes, sealing a space between said support case and said handset. 35. A receiver according to claim 34 further comprising an angular spacer placed between said support case and said rubber sheet.