US3760120A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lockout selection circuit
Assignee: AG Communication Systems Corp
•
Filing: 1972-07-27
•
Granted: 1973-09-18
•
Expires: 1992-07-27
Abstract
Abstract In a system in which a number of units operate one at a time with common apparatus, a lockout circuit comprises a set of NAND gates, one for each unit. Each gate has a seize input normally at logical ''''0'''' from its unit and an enable output normally at logical ''''1'''' thereto. The output of each gate is also connected to an input of each of the others, so that only one gate at a time may have a ''''0'''' output to enable its unit for operation with the common apparatus.
Inventors
- 👤 T Moorehead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:40
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/14; G06F13/16; G06F13/18; H; H03; H03K; H03K19/00; H03K19/0175; H03K19/017545; H04; H04Q; H04Q3/00; H04Q3/42; H04Q3/54; H04Q3/545; H04Q3/54541; H04Q3/5455
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
333 words
A lockout selection circuit for use in a system in which a plurality of units may operate in conjunction with common apparatus one at a Time, said lockout circuit comprising a plurality of gate means with an individual gate means for each unit; the gate means being each of a type having a plurality of inputs and an output in which responsive to at least one input of a gate means having a signal at a first level the output signal is at a second level, and responsive to all of the inputs of a gate means having signals at the second level the output signal is at the first level; each gate means has a number of inputs equal to the number of said units, one input being a seize lead connected to its own unit and its output being an enable lead connected to its own unit, the other inputs being connected respectively to the outputs of the other gate means; the seize lead of each idle unit having a signal at the first level so that its enable lead is at the second level whereby with all units idle all of the output signals are at the second level, the seize lead of any unit which is active and desiring to use the common apparatus having a signal at the second level, one gate means having its seize lead signal at the second level producing the first level at its output which inhibits all the other gate means to maintain their output signals at the second level regardless of the signal level on their seize lead, while the gate means having the first level at its output via its enable lead signals its own unit to operate with the common apparatus, and as soon as it finishes its operation and returns its seize lead to the first level, to permit another unit having its seize lead at the second level to change its enable lead signal to the first level.
Claim 2
Dependent Claim
333 words
A lockout selection circuit for use in a system in which a plurality of units may operate in conjunction with common apparatus one at a Time, said lockout circuit comprising a plurality of gate means with an individual gate means for each unit; the gate means being each of a type having a plurality of inputs and an output in which responsive to at least one input of a gate means having a signal at a first level the output signal is at a second level, and responsive to all of the inputs of a gate means having signals at the second level the output signal is at the first level; each gate means has a number of inputs equal to the number of said units, one input being a seize lead connected to its own unit and its output being an enable lead connected to its own unit, the other inputs being connected respectively to the outputs of the other gate means; the seize lead of each idle unit having a signal at the first level so that its enable lead is at the second level whereby with all units idle all of the output signals are at the second level, the seize lead of any unit which is active and desiring to use the common apparatus having a signal at the second level, one gate means having its seize lead signal at the second level producing the first level at its output which inhibits all the other gate means to maintain their output signals at the second level regardless of the signal level on their seize lead, while the gate means having the first level at its output via its enable lead signals its own unit to operate with the common apparatus, and as soon as it finishes its operation and returns its seize lead to the first level, to permit another unit having its seize lead at the second level to change its enable lead signal to the first level.
Claim 3
Dependent Claim
37 words
A lockout circuit as claimed in claim 1, wherein each of said gate means is a NAND gate, the first level is low for a logical ''''0'''', and the second level is high for a logical ''''1''''.
References Cited (Backward Citations)
US2914747A
Cited
US2928008A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |