Patent US3818247A successfully refreshed from Google Patents.
US3818247A
Expired / Lapsed
US
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Two-lead electrical control apparatus
Assignee: Robertshaw Controls Co
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Filing: 1972-04-03
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Granted: 1974-06-18
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Expires: 1992-04-03
Abstract
Abstract Two-lead electrical control apparatus including a pair of gate controlled switches that form a control switch and a triggering switch, the control switch being connected across a power source and through a load by means of a pair of run leads. A voltage divider circuit is connected with the gate of the triggering switch and includes sensing means responsive to a pre-selected condition to impose a recurring triggering signal on the triggering switch to render such triggering switch conductive to supply a triggering signal to the control switch to thereby trigger the control switch and provide full source voltage across the load.
Inventors
- 👤 W Chambers
- 👤 C Olander
- 👤 J Brooks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:26
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/72; H03K17/725
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
247 words
Two-lead electrical control apparatus comprising: load means including a one end and an other end adapted to receive at one end thereof an electrical A.C. sgnal, said load means including a first and second load connected in parallel between said one and other ends, first and second one way opposed current blocking means connected in series with said respective first and second loads; gate controlled control switch means connected in circuit with the other end of said load means and including a gate terminal for controlling the conduction thereof; a triggering circuit connected to the gate terminal of said control switch means including triggering switch means responsive to a selected electrical signal difference to be rendered conductive and impose a triggering signal on said gate terminal; voltage divider circuit means connected to said triggering switch means and including sensing means responsive to a predetermined condition to impose a first electrical signal on the gate terminal of said triggering switch means; and circuit means adapted to be connected across the A.C. signal and connected to said load means including compensation means for regulating a second electrical signal to be compared with said first electrical signal to produce said signal difference whereby when said sensing means senses said predetermined condition, said electrical signal difference will be imposed on said triggering switch means to render said triggering switch means conductive to impose said triggering signal on said control switch means to electrically couple said load means across said power source.
Claim 2
Dependent Claim
247 words
Two-lead electrical control apparatus comprising: load means including a one end and an other end adapted to receive at one end thereof an electrical A.C. sgnal, said load means including a first and second load connected in parallel between said one and other ends, first and second one way opposed current blocking means connected in series with said respective first and second loads; gate controlled control switch means connected in circuit with the other end of said load means and including a gate terminal for controlling the conduction thereof; a triggering circuit connected to the gate terminal of said control switch means including triggering switch means responsive to a selected electrical signal difference to be rendered conductive and impose a triggering signal on said gate terminal; voltage divider circuit means connected to said triggering switch means and including sensing means responsive to a predetermined condition to impose a first electrical signal on the gate terminal of said triggering switch means; and circuit means adapted to be connected across the A.C. signal and connected to said load means including compensation means for regulating a second electrical signal to be compared with said first electrical signal to produce said signal difference whereby when said sensing means senses said predetermined condition, said electrical signal difference will be imposed on said triggering switch means to render said triggering switch means conductive to impose said triggering signal on said control switch means to electrically couple said load means across said power source.
Claim 3
Dependent Claim
56 words
Two-lead electrical control apparatus as set forth in claim 1 further comprising: two position switch means connected across said control switch means and operative to be switched to one position to direct current in one direction through said first load and to a second position to direct current in the opposite direction through said second load.
Claim 4
Dependent Claim
61 words
Two-lead electrical control apparatus as set forth in claim 1 wherein: said control switch means is a silicon controlled rectifier having the anode to cathode circuit thereof connected across said voltage divider Circuit means; and said triggering switch means is a programmable unijunction transistor having the anode to cathode circuit thereof connected with the gate terminal of said silicon controlled rectifier.
Claim 5
Dependent Claim
89 words
Two-lead electrical control apparatus as set forth in claim 1 wherein: said voltage divider circuit means includes first, second, third and fourth legs formed by respective first voltage divider resistance means, temperature responsive resistor means and second and third voltage divider resistance means and circuit means connecting said first and second legs in series and forming a first node therebetween and said third and fourth legs in series to form a second node, said circuit means further connecting said first and second nodes with the said triggering switch means.
Claim 6
Dependent Claim
111 words
Two-lead electrical control apparatus as set forth in claim 1 wherein: at least one of sid switch means is forward biased and said apparatus includes selector switch means connected across said control switch means and across said voltage divider circuit means; and said load means including first and second loads connected in parallel with one another and in series with said selector switch means and oppositely directed circuit blocking means connected in series with said respective first and second loads whereby said selector switch means may be switched to reverse the polarity across said loads and said one switch means when the polarity of said voltage divider circuit means is reversed.
Claim 7
Dependent Claim
89 words
Two-lead electrical control apparatus as set forth in claim 1 that includes: said compensation means including a compensator circuit connected in parallel with one side of said triggering switch means and including a current limiting resistor and compensating switch means responsive to predetermined voltage of said second electrical signal thereacross to be rendered conductive and initiate current flow through said compensating resistor and one leg of said triggering switch means at a rate proportional to the amount by which said predetermined voltage of said second electrical signal is exceeded.
Claim 8
Dependent Claim
56 words
Two-lead electrical control apparatus as set forth in claim 1 for use with an A.C. source and that includes: discrimination means connectd with said load means and said voltage divider circuit means for responding to the unbalance of said voltage divider circuit means in one direction to direct current in one direction through said load means.
Claim 9
Dependent Claim
42 words
Two-lead electrical control apparatus as set forth in claim 7 wherein: said load means includes first and second loads; and said discriminator means includes rectifier means and oppositely directed one-way current blocking means connected in series with said first and second loads.
Claim 10
Dependent Claim
90 words
Two-lead electrical control apparatus as set forth in claim 8 that includes: two position selector switch means connected on one side with said discriminator means; and circuit means connected with the side of said selector switch means opposite said one side having said first load connected with a first contact of said selector switch means and providing for two-way current flow and said second load including one-way current blocking means for providing a current path from one of said loads but blocking current flow from the other of said loads.
Claim 11
Dependent Claim
169 words
Two-lead electrical control apparatus comprising: load means adapted to receive at one end thereof an electrical A.C. signal; gate controlled control switch means connected in circuit with the other end of said load means; a first voltage divider circuit means connected across said A.C. signal and including sensing means responsive to a predetermined condition to produce a first electrical signal of an amplitude corresponding to the amplitude of said sensed condition; a second voltage divider circuit comprising an upper resistive leg and a lower resistive leg connected in common at respective one ends thereof to provide a second electrical signal tHereat; triggering circuit means connected to receive said first and second electrical signals to produce a gating signal to said gate controlled control switch means upon a predetermined combination of said first and second electrical signals for rendering said gate controlled control switch means conductive; and rectifying means respectively connected in series to said upper and lower resistive legs for selectively imposing alternate halves of said A.C. signal thereon.
Claim 12
Dependent Claim
169 words
Two-lead electrical control apparatus comprising: load means adapted to receive at one end thereof an electrical A.C. signal; gate controlled control switch means connected in circuit with the other end of said load means; a first voltage divider circuit means connected across said A.C. signal and including sensing means responsive to a predetermined condition to produce a first electrical signal of an amplitude corresponding to the amplitude of said sensed condition; a second voltage divider circuit comprising an upper resistive leg and a lower resistive leg connected in common at respective one ends thereof to provide a second electrical signal tHereat; triggering circuit means connected to receive said first and second electrical signals to produce a gating signal to said gate controlled control switch means upon a predetermined combination of said first and second electrical signals for rendering said gate controlled control switch means conductive; and rectifying means respectively connected in series to said upper and lower resistive legs for selectively imposing alternate halves of said A.C. signal thereon.
Claim 13
Dependent Claim
54 words
Two-lead electrical control apparatus according to claim 10 wherein: said load means including a first and second load respectively connected to receive at one end thereof said A.C. signal, and first and second rectifying means disposed respectively in parallel with said first and second loads for shunting opposite halves of said A.C. signal thereacross.
Claim 14
Dependent Claim
57 words
Two-lead electrical control apparatus according to claim 10 wherein: said control switch means is a silicon controlled rectifier having the anode to cathode circuit thereof operatively connected across said A.C. signal; and said triggering circuit means is a programmable unijunction transistor having the anode to cathode circuit thereof connected with the gate of said silicon controlled rectifier.
Claim 15
Dependent Claim
39 words
Two-lead electrical control apparatus according to claim 11 further comprising: semiconductor means interposed between said triggering circuit means and said gate controlled control switch means for being rendered conductive when said triggering circuit means is producing said gating signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |