US3575607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement for indicating change of state in one or several bistable elements
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1969-04-23
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Granted: 1971-04-20
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Expires: 1989-04-23
Abstract
Abstract A circuit arrangement for indicating changes of state in one or several bistable elements, e.g. relays in the interval between two successive scannings of the elements. Each bistable element controls two make-and-break contacts, between which a capacitor is connected, a change of state of the element implying that the polarity of the appertaining capacitor is reversed. This reversing changes the state of an indication arrangement which is subject to the scannings, a change of state of the indication arrangement being recorded upon a scanning indicating that one or several bistable elements have changed their states.
Inventors
- 👤 Nils Herbert Edstrom
- 👤 Goran Anders Henrik Hemdal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:13
CPC Classifications
G; G08; G08C; G08C15/00; G08C15/06; G08C15/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
262 words
Arrangement for indicating a change of state in one or several bistable elements between two successive scannings of an indication arrangement common for all said elements, comprising a plurality of rectifiers, a first and a second make-and-break contact associated with each of said bistable elements, said two contacts being in a first or a second position in dependence on the state of the associated bistable element and of which makeand-break contacts the first one is connected to ground in the first state and the second one in the second state, while the first contact in the second state and the second contact in the first state are connected to one electrode of one of said rectifiers associated with the respective bistable element, a capacitor being connected between each of said make-and-break contacts, the second electrode in all rectifiers being connected to a common connection point, said rectifiers being connected and poled in such a manner that a current cannot flow between said capacitors, the connection point having a reference potential as long as no change of state has taken place after a scanning, the change of state of one of said bistable elements resulting in the polarity of the associated capacitor being reversed and the potential of said connection point being changed, said connection point being connected to said indication arrangement, the state of which is changed upon said change of potential, a changed state of the indication arrangement upon scanning indicating said change of state of said bistable elements, and the state of the indication arrangement being restored after the scanning.
Claim 2
Dependent Claim
262 words
Arrangement for indicating a change of state in one or several bistable elements between two successive scannings of an indication arrangement common for all said elements, comprising a plurality of rectifiers, a first and a second make-and-break contact associated with each of said bistable elements, said two contacts being in a first or a second position in dependence on the state of the associated bistable element and of which makeand-break contacts the first one is connected to ground in the first state and the second one in the second state, while the first contact in the second state and the second contact in the first state are connected to one electrode of one of said rectifiers associated with the respective bistable element, a capacitor being connected between each of said make-and-break contacts, the second electrode in all rectifiers being connected to a common connection point, said rectifiers being connected and poled in such a manner that a current cannot flow between said capacitors, the connection point having a reference potential as long as no change of state has taken place after a scanning, the change of state of one of said bistable elements resulting in the polarity of the associated capacitor being reversed and the potential of said connection point being changed, said connection point being connected to said indication arrangement, the state of which is changed upon said change of potential, a changed state of the indication arrangement upon scanning indicating said change of state of said bistable elements, and the state of the indication arrangement being restored after the scanning.
Claim 3
Dependent Claim
89 words
Arrangement according to claim 1, wherein said indication arrangement is a current sensing device connected to a direct current voltage source of said reference potential via a contact which closes for each scanning, a current flowing through said current sensing device when said contact is closed if the potential at said connection point has been changed, and said connection point being given the same reference potential at the same time as an indication is obtained at an output of said current sensing device constituting the output of the arrangement.
Claim 4
Dependent Claim
159 words
Arrangement according to claim 1, wherein said connection point is on the one hand connected to a direct current voltage source of said reference potential via a resistor and on the other hand connected to ground via a series connection of a capacitor and a resistor, a bistable flip-flop circuit, the connection point of said resistor and said capacitor being connected to one trigger input of said bistable flip-flop circuit, so that a pulse, derived from the potential change at said point sets the flip-flop circuit in a first stable state, in which an output of said flip-flop circuit is activated, said output being connected to the output of the arrangement via a contact which closes upon each scanning of a scanning signal, and that upon scanning the scanning signal is also supplied to a second trigger input of said bistable flip-flop circuit via a delay circuit implying that said flip-flop circuit is restored to the second stable state.
References Cited (Backward Citations)
US2800645A
Cited
US3452271A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |