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US3573387A Expired / Lapsed US ⏱️ 0.0 years remaining

Screening of misdialed calls in step-by-step local level hunting connectors

Assignee: AT&T Inc
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Filing: 1969-05-06
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Granted: 1971-04-06
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Expires: 1989-05-06
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Abstract

Abstract A circuit is disclosed for screening misdialed calls in a local level hunting connector which may have line appearances both for normal subscribers as well as for a subscriber receiving an especially high volume of calls. The normal subscribers appearing on the connector are assigned directory numbers ending in 1 while the high volume subscriber is assigned a specific ''''tens'''' digit. The connector is prevented from responding directly to any tens digit until the first pulse of the units digit is received. The connector is then ''''unlocked'''' and permitted to hunt as it normally would. However, if a subsequent pulse is received, indicating a units digit other than 1, the normally grounded commutator segment corresponding to the tens digit becomes ungrounded and a commutator segment connected to an intercept position is grounded unless the tens digit is the specific one assigned to the high volume subscriber.

Inventors

  • 👤 Carl R Nebe
  • 👤 James T Switzer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 21:40
CPC Classifications
H; H04; H04Q; H04Q3/00

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 128 words
In a telephone switching system having a local level hunting connector for responding to a predetermined digit of a called telephone number to establish a connection to one of a plurality of telephone lines, said connector having an intercept level for calls which are not to be completed to any of said lines, a circuit comprising: means for storing said predetermined digit; means for preventing the normal response of said connector to said stored digit; means responsive to the first pulse of a subsequent digit of said called number for permitting said connector to respond to said stored digit; and intercept means responsive to a second pulse of said subsequent digit for preventing said connector from responding to said stored digit and for marking said intercept level thereof.
Claim 2
Dependent Claim 128 words
In a telephone switching system having a local level hunting connector for responding to a predetermined digit of a called telephone number to establish a connection to one of a plurality of telephone lines, said connector having an intercept level for calls which are not to be completed to any of said lines, a circuit comprising: means for storing said predetermined digit; means for preventing the normal response of said connector to said stored digit; means responsive to the first pulse of a subsequent digit of said called number for permitting said connector to respond to said stored digit; and intercept means responsive to a second pulse of said subsequent digit for preventing said connector from responding to said stored digit and for marking said intercept level thereof.
Claim 3
Dependent Claim 27 words
A circuit in accordance with claim 1 further including means responsive to the storage of a particular value of said predetermined digit for inhibiting said intercept means.
Claim 4
Dependent Claim 133 words
A local level hunting connector switch for use in a step-by-step switching system, said switch being normally arranged to record one of a sequence of dialed telephone number digits, to mark a segment of its vertical commutator corresponding to said one digit, to automatically step to the level signified by said marked commutator segment and to automatically select an idle line on said level, said switch including a dialed number screening circuit comprising: means for interrupting the normal response of said switch after said one of said sequence of digits is recorded; means responsive to the first pulse of a subsequently dialed digit for continuing said normal response of said switch; and control means responsive to a second pulse of said subsequently dialed digit for again interrupting said normal response of said switch.
Claim 5
Dependent Claim 133 words
A local level hunting connector switch for use in a step-by-step switching system, said switch being normally arranged to record one of a sequence of dialed telephone number digits, to mark a segment of its vertical commutator corresponding to said one digit, to automatically step to the level signified by said marked commutator segment and to automatically select an idle line on said level, said switch including a dialed number screening circuit comprising: means for interrupting the normal response of said switch after said one of said sequence of digits is recorded; means responsive to the first pulse of a subsequently dialed digit for continuing said normal response of said switch; and control means responsive to a second pulse of said subsequently dialed digit for again interrupting said normal response of said switch.
Claim 6
Dependent Claim 64 words
A switch in accordance with claim 3 further including: an intercept position connected to all the lines appearing on a predetermined level of said switch; and wherein said control means includes: means responsive to said second pulse for marking said predetermined switch level and for automatically stepping said switch to said predetermined level, so that said calling party is connected to said intercept position.
Claim 7
Dependent Claim 31 words
A switch in accordance with claim 3 further including means responsive to the recording of a specific value of said one of said sequence of digits for inhibiting said control means.
Claim 8
Dependent Claim 43 words
A switch in accordance with claim 5 wherein said control means includes: relay means energized by said first pulse and operable in response to said second pulse; and wherein said inhibiting means includes: means for shunting said relay means to prevent its operation.
Claim 9
Dependent Claim 140 words
In a telephone switching system, the combination comprising: a calling telephone; an intercept position; switch means having a plurality of levels selectable in accordance with the value of a first digit dialed by said calling telephone, said intercept position appearing at one of said levels of said switch means; selector means responsive to said first digit for selecting the level of said switch means corresponding thereto; screening means responsive to any of a plurality of predetermined second digits dialed by said calling telephone for controlling said seleCtor means to select said one level; and override means responsive to a particular value of said first digit for preventing said screening means from controlling said selector means to select said one level and for permitting said selector means to select said level corresponding to said first digit dialed by said calling telephone.
Claim 10
Dependent Claim 140 words
In a telephone switching system, the combination comprising: a calling telephone; an intercept position; switch means having a plurality of levels selectable in accordance with the value of a first digit dialed by said calling telephone, said intercept position appearing at one of said levels of said switch means; selector means responsive to said first digit for selecting the level of said switch means corresponding thereto; screening means responsive to any of a plurality of predetermined second digits dialed by said calling telephone for controlling said seleCtor means to select said one level; and override means responsive to a particular value of said first digit for preventing said screening means from controlling said selector means to select said one level and for permitting said selector means to select said level corresponding to said first digit dialed by said calling telephone.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-04-05 1974-10-05 1975-04-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-04-05 1978-10-05 1979-04-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-04-05 1982-10-05 1983-04-06 $7700.00 Window Closed / Lapsed

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