← Back to Patent Explorer
US4149098A Expired / Lapsed US ⏱️ 0.0 years remaining

A. C. Switching system

Assignee: United States Department of the Navy
•
Filing: 1976-05-20
•
Granted: 1979-04-10
•
Expires: 1996-05-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An A.C. power return to provide a path to ground according to predeterminedogic. A potential switch stage is coupled to a phase inverter which is coupled to an output stage. Impressed potentials in the phase inverter stage are selected to assure that a path to ground will only exist when an on logic signal is present. Power transistors in the output stage minimize power dissipation within the switch.

Inventors

  • 👤 Malcolm T. Wright

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 14:06
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/60; H03K17/68; H03K2217/00; H03K2217/0036

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 109 words
An A.C. switch which comprises: (a) a potential switch stage for receiving a control signal; (b) an output stage electrically coupled to an A.C. power supply; and (c) a phase inverter electrically coupled between said potential switch stage and said output stage, said phase inverter including: (i) a first impressed voltage; (ii) a second impressed voltage; (iii) said first impressed voltage being positive and said second impressed voltage being negative; and (iv) said first impressed voltage being greater in positive value than any positive-going cycle of said A.C. power supply and said second impressed voltage being greater in negative value than any negative-going cycle of said A.C. power supply.
Claim 2
Dependent Claim 109 words
An A.C. switch which comprises: (a) a potential switch stage for receiving a control signal; (b) an output stage electrically coupled to an A.C. power supply; and (c) a phase inverter electrically coupled between said potential switch stage and said output stage, said phase inverter including: (i) a first impressed voltage; (ii) a second impressed voltage; (iii) said first impressed voltage being positive and said second impressed voltage being negative; and (iv) said first impressed voltage being greater in positive value than any positive-going cycle of said A.C. power supply and said second impressed voltage being greater in negative value than any negative-going cycle of said A.C. power supply.
Claim 3
Dependent Claim 75 words
An A.C. switch as described in claim 1 wherein said output stage comprises: (a) a first half adapted to respond to cycles of one polarity of said A.C. load; (b) a second half adapted to respond to cycles of the opposite polarity of said A.C. load; and (c) an electrical ground to provide an electrical path for said A.C. load when said control signal is impressed upon said A.C. switch at said potential switch stage.
Claim 4
Dependent Claim 127 words
An A.C. switch as described in claim 2 wherein each of said halves of said output stage comprises: (a) a power transistor in common emitter configuration; (b) the base of said power transistor in series with the collector of a driver transistor; (c) said driver transistor having its base coupled to said near-zero potential output of said phase inverter; (d) the emitter of said driver transistor in electrical connection with the collector of said power transistor; and (e) a protective diode located between the electrical junction of the emitter of said driver transistor and the collector of said power transistor and said A.C. load so that said A.C. load provides the bias voltage for said half of said output stage during the cycles having the proper polarity.
Claim 5
Dependent Claim 40 words
An A.C. switch as recited in claim 3 wherein said potential switch stage comprises a transistor in a common-emitter configuration with said control signal input to the base and with the collector connected to the input of said phase inverter.
Claim 6
Dependent Claim 111 words
An A.C. switch as recited in claim 2 wherein said phase inverter further comprises a transistor with the output of said potential switch stage connected to the base through a resistor to provide a first near-zero voltage output when said control signal is applied, the base being connected to the input of said first half of said output stage, with bias resistors connected between said first impressed voltage and the emitter and between said second impressed voltage and the collector to produce a second near-zero voltage output at the collector when said control signal is applied, the collector being connected to the input of said second half of said output stage.
Claim 7
Dependent Claim 26 words
An A.C. switch as described in claims 4 or 5 wherein said control signal source comprises a D.C. logic input coupled to said potential switch stage.
Claim 8
Dependent Claim 15 words
An A.C. switch as described in claim 6 wherein said logic input comprises TTL logic.

References Cited (Backward Citations)

US3157870A Cited
NL6617000A Cited
US3417292A Cited
US3538353A Cited
US3448395A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-04-09 1982-10-09 1983-04-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-04-09 1986-10-09 1987-04-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-04-09 1990-10-09 1991-04-10 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag