← Back to Patent Explorer
US4544829A Expired / Lapsed US ⏱️ 0.0 years remaining

Electric soldering iron having a PTC heating element

Assignee: TDK Corp
•
Filing: 1984-02-10
•
Granted: 1985-10-01
•
Expires: 2004-02-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A soldering iron is heated by electric resistance heating elements comprising barium titanate PTC thermistors. The soldering iron has an elongated copper bit with a cone shaped bit tip and an elongated back body having a generally rectangular cross section coupled to the bit tip. A pair of flat PTC thermistor heater assemblies sandwich the back body of the bit and are in thermal contact therewith. The heater assemblies are pressed against the back body of the bit with spring contact. A hand-grip is coupled with the bit. The total contact area S 1 between the PTC thermistor heater assemblies and the back body is in the range from 1.0 cm 2 to 25 cm 2 and the transverse cross sectional area S 2 of the back body is in the range from 0.1 cm 2 to 3.0 cm 2 .

Inventors

  • 👤 Shichiro Adachi
  • 👤 Sho Kotani

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 17:43
CPC Classifications
B; B23; B23K; B23K3/00; B23K3/02; B23K3/03

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 150 words
A soldering iron comprising: an elongated bit with a cone shaped bit tip and an elongated back body having a generally rectangular cross-section; a pair of heater assemblies sandwiching the back body of the bit so as to be in thermal contact therewith; lead wires coupled to said heater assemblies to supply power to the soldering iron; and a hand-grip coupled with the bit; each of said heater assemblies comprising a PTC thermistor having a positive temperature coefficient of resistance as a heater; means for pressing said heater assemblies against the back body of the bit with spring contact; the total contact area S 1 between said PTC thermistors and said back body being in the range from 1.0 cm 2 to 25 cm 2 and the transverse cross sectional area S 2 of the back body being in the range from 0.1 cm 2 to 3.0 cm 2 .
Claim 2
Dependent Claim 150 words
A soldering iron comprising: an elongated bit with a cone shaped bit tip and an elongated back body having a generally rectangular cross-section; a pair of heater assemblies sandwiching the back body of the bit so as to be in thermal contact therewith; lead wires coupled to said heater assemblies to supply power to the soldering iron; and a hand-grip coupled with the bit; each of said heater assemblies comprising a PTC thermistor having a positive temperature coefficient of resistance as a heater; means for pressing said heater assemblies against the back body of the bit with spring contact; the total contact area S 1 between said PTC thermistors and said back body being in the range from 1.0 cm 2 to 25 cm 2 and the transverse cross sectional area S 2 of the back body being in the range from 0.1 cm 2 to 3.0 cm 2 .
Claim 3
Dependent Claim 14 words
A soldering iron according to claim 1, wherein said bit is made of copper.
Claim 4
Dependent Claim 17 words
A soldering iron according to claim 1, wherein each of said heater assemblies has a flat shape.

References Cited (Backward Citations)

DE385657C Cited
US1106476A Cited
GB191507492A Cited
US1370136A Cited
US1422721A Cited
US1363473A Cited
US3518407A Cited
US3584190A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-09-30 1989-04-01 1989-10-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-09-30 1993-04-01 1993-10-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-09-30 1997-04-01 1997-10-01 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag