US3562596A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noncoded digit detection circuit for electrical combination lock
Assignee: Nortel Networks Ltd
•
Filing: 1968-07-16
•
Granted: 1971-02-09
•
Expires: 1988-07-16
Abstract
Abstract This disclosure relates to an electrical combination lock of the type comprising n key circuits each having a digit key, m digit selecting switches each having n inputs connected to an associated digit key and one wiper output which is positioned to contact one of the inputs in accordance with a preselected code, and a chain of m relays connected to an associated selecting switch, each relay having a contact in the operating path of the following relay and such relays being sequentially operated one by one to open the electrical lock. In accordance with the invention, the above electrical lock is provided with a gate circuit having a first input connected to the wipers of the selecting switches, a second input connected to the key circuits and an output circuit adapted to open the operating path of the chain of relays when a noncoded digit is keyed thus restoring the electrical combination lock to normal.
Inventors
- 👤 Joseph Scheuer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:24
CPC Classifications
G; G07; G07C; G07C9/00; G07C9/00174; G07C9/00658; G07C9/00674; G07C9/0069
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
223 words
A circuit for an electrical combination lock responsive to a preselected m digit code selected from a choice of n digits comprising: a. n key circuits each including a normally open digit key; b. m digit-selecting switches each having n input contacts connected to an associated digit key and a wiper for connection to a prEdetermined contact of each selecting switch in accordance with the preselected code; c. a chain of m relays, each relay being connected to the wiper of an associated selecting switch, each relay when energized conditioning an operating path for the following relay in the chain, the last relay in the chain, when energized, completing an operating path for the clock; d. a source of discrete energy connected to said key circuit to operate said relays one by one upon operation of the digit keys in accordance with the preselected code to establish said operating path for the lock; and e. means connected to all of the input contacts and wipers of said digit-selecting switches for detecting potentials at any of said contacts and wires, said means being responsive to a potential appearing only at the input contact of a selector switch as indicating the keying of a noncoded digit for deenergizing any energized ones of said relays of said chain to return said lock to an unkeyed condition.
Claim 2
Dependent Claim
223 words
A circuit for an electrical combination lock responsive to a preselected m digit code selected from a choice of n digits comprising: a. n key circuits each including a normally open digit key; b. m digit-selecting switches each having n input contacts connected to an associated digit key and a wiper for connection to a prEdetermined contact of each selecting switch in accordance with the preselected code; c. a chain of m relays, each relay being connected to the wiper of an associated selecting switch, each relay when energized conditioning an operating path for the following relay in the chain, the last relay in the chain, when energized, completing an operating path for the clock; d. a source of discrete energy connected to said key circuit to operate said relays one by one upon operation of the digit keys in accordance with the preselected code to establish said operating path for the lock; and e. means connected to all of the input contacts and wipers of said digit-selecting switches for detecting potentials at any of said contacts and wires, said means being responsive to a potential appearing only at the input contact of a selector switch as indicating the keying of a noncoded digit for deenergizing any energized ones of said relays of said chain to return said lock to an unkeyed condition.
Claim 3
Dependent Claim
76 words
A circuit as defined in claim 1 wherein said potential detecting means comprises a gate circuit having a first input connected to each of said wipers, a second input connected to said key circuit, and an output circuit adapted when energized to remove the source of discrete energy from the relays of said chain of m relays, the gate circuit being responsive to a potential appearing only at the second input to energize the output circuit.
Claim 4
Dependent Claim
51 words
A circuit as defined in claim 2 wherein said output circuit includes a release relay having normally closed contacts in the operating path of each of the relays in said chain of m relays, said release relay being energized to open said normally closed contacts when said output circuit is energized.
Claim 5
Dependent Claim
139 words
A circuit as defined in claim 2 wherein said gate circuit includes a first transistor responsive to said first input, a second transistor responsive to said second input, and a third transistor responsive to said first and second transistors, said second and third transistors being connected in the output circuit of said gate circuit, the simultaneous appearance of a potential at said first and second inputs in response to keying of a coded digit rendering said second transistor nonconductive to prevent energization of the output circuit, the appearance of a potential at said second input alone in response to keying of a noncoded digit rendering said second and third transistor conductive to energize the output circuit, and thereby deenergize any energized ones of the relays of said chain of m relays to return said lock to an unkeyed condition.
References Cited (Backward Citations)
US3380024A
Cited
US3441808A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |