← Back to Patent Explorer
US4121277A Expired / Lapsed US ⏱️ 0.0 years remaining

High current protection in a solid electrolytic capacitor

Assignee: Siemens AG
•
Filing: 1976-06-28
•
Granted: 1978-10-17
•
Expires: 1996-06-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract When solid electrolytic capacitors are connected with incorrect polarities to a current source, short circuit currents flow. The capacitors may heat up to such an extent that the capacitor internal portions ignite and the casings of the capacitors, such as plastic casings, begin to burn. By providing a gap between a cathode terminal and a cathode contacting within the capacitor whereby the gap is bridged with a meltable circuit breaker such as solder, burning of the capacitor may be prevented. When internal portions of the capacitor heat due to incorrect polarity connections, the solder will melt and the current will be interrupted.

Inventors

  • 👤 Ferdinand Hilbert

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 09:01
CPC Classifications
H; H01; H01G; H01G2/00; H01G2/14; H01G9/00; H01G9/0003

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 129 words
A solid electrolytic capacitor comprising: (a) an anode; (b) an oxide layer on said anode as a dielectric; (c) a semiconductive electrolyte on said oxide layer as a cathode; (d) a cathode contacting layer on said electrolyte; (e) an anode terminal connected to said anode; (f) a cathode terminal; (g) a plastic case with said anode, said cathode, and said cathode contacting layer mounted therein as a central member, said cathode terminal being spaced from said central member to form a spacing therebetween; (h) a meltable circuit breaker bridged between said cathode terminal and said cathode contacting layer in said spacing; and (i) a diameter of said meltable circuit breaker approximately corresponding to said spacing bridged by said circuit breaker between said cathode terminal and said cathode contacting layer.
Claim 2
Dependent Claim 129 words
A solid electrolytic capacitor comprising: (a) an anode; (b) an oxide layer on said anode as a dielectric; (c) a semiconductive electrolyte on said oxide layer as a cathode; (d) a cathode contacting layer on said electrolyte; (e) an anode terminal connected to said anode; (f) a cathode terminal; (g) a plastic case with said anode, said cathode, and said cathode contacting layer mounted therein as a central member, said cathode terminal being spaced from said central member to form a spacing therebetween; (h) a meltable circuit breaker bridged between said cathode terminal and said cathode contacting layer in said spacing; and (i) a diameter of said meltable circuit breaker approximately corresponding to said spacing bridged by said circuit breaker between said cathode terminal and said cathode contacting layer.
Claim 3
Dependent Claim 16 words
A solid electrolytic capacitor in accordance with claim 1, characterized in that said anode comprises tantalum.
Claim 4
Dependent Claim 18 words
A solid electrolytic capacitor in accordance with claim 1 characterized in that said semiconductive electrolyte is manganese dioxide.
Claim 5
Dependent Claim 25 words
A solid electrolytic capacitor in accordance with claim 1 characterized in that said cathode contacting layer comprises a graphite layer and a conductive silver-lacquer layer.
Claim 6
Dependent Claim 30 words
A solid electrolytic capacitor in accordance with claim 1 characterized in that said meltable circuit breaker consists of a solder metal with a melting point of less than 200° C.
Claim 7
Dependent Claim 32 words
A solid electrolytic capacitor in accordance with claim 1 characterized in that said anode has a diameter of 4.5 mm and said distance bridged by said meltable circuit breaker is 0.5 mm.
Claim 8
Dependent Claim 19 words
A solid electrolytic capacitor of claim 1 in which said circuit breaker comprises silver-lead solder with approximately 60% tin.
Claim 9
Dependent Claim 119 words
A solid electrolytic capacitor comprising: (a) an anode; (b) a cathode comprising a semiconductive electrolyte and a cathode contacting layer; (c) a dielectric between said anode and said cathode; (d) an anode terminal connected to said anode; (e) a cathode terminal; (f) a plastic case with said anode and said cathode mounted therein as a central member, said cathode terminal being spaced alongside of an edge of said central member to form a spacing therebetween; and (g) a meltable circuit breaker bridged between said cathode terminal and said cathode within a portion of said spacing, a diameter of said meltable circuit breaker approximately corresponding to the spacing bridged by the circuit breaker between said cathode terminal and said cathode.
Claim 10
Dependent Claim 119 words
A solid electrolytic capacitor comprising: (a) an anode; (b) a cathode comprising a semiconductive electrolyte and a cathode contacting layer; (c) a dielectric between said anode and said cathode; (d) an anode terminal connected to said anode; (e) a cathode terminal; (f) a plastic case with said anode and said cathode mounted therein as a central member, said cathode terminal being spaced alongside of an edge of said central member to form a spacing therebetween; and (g) a meltable circuit breaker bridged between said cathode terminal and said cathode within a portion of said spacing, a diameter of said meltable circuit breaker approximately corresponding to the spacing bridged by the circuit breaker between said cathode terminal and said cathode.

References Cited (Backward Citations)

US3236976A Cited
US3638083A Cited
US3935516A Cited
US3971970A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-16 1982-04-17 1982-10-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-16 1986-04-17 1986-10-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-16 1990-04-17 1990-10-17 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag