US3885103A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic branch exchange using time division switching
Assignee: TELE RESOURCES Inc
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Filing: 1973-07-02
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Granted: 1975-05-20
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Expires: 1993-07-02
Abstract
Abstract A time division branch exchange for a telephony system includes a constantly recirculating temporary memory in which equipment addresses and other information relating to active time slots is recorded. This information is decoded as the temporary memory recirculates and the output is provided to a time division switch which gates audiopaths to the equipment interconnected through each time slot. The contents of the temporary memory is updated as necessary when a piece of equipment, e.g., a station, which has changed status is scanned by a line counter.
Inventors
- 👤 William Ralph Smith
- 👤 Herman Deutsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:51
CPC Classifications
G; G04; G04F; G04F10/00; G04F10/04; H; H04; H04J; H04J3/00; H04J3/02; H04J3/04; H04J3/047; H04M; H04M3/00; H04M3/42; H04M3/56; H04M3/561; H04M3/58; H04Q; H04Q11/00; H04Q11/04
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
134 words
A time division multiplex automatic branch exchange for a telephony system comprising: a time division switch for gating signals between discrete audio paths during selected periodically recurring time slots; a temporary memory for recording information relating to each recurring time slot defined by the switch; decoder means for reading in sequence from the temporary memory information relating to each time slot of the system and providing inputs to said time division switch identifying the paths to be gated together during that time slot; a permament memory having recorded therein a series of coded operating instructions for establishing connections via the time division switch; and update circuit means responsive to said permanent memory for recording in the temporary memory equipment addresses corresponding to equipment within the system to be interconnected through the time division switch.
Claim 2
Dependent Claim
134 words
A time division multiplex automatic branch exchange for a telephony system comprising: a time division switch for gating signals between discrete audio paths during selected periodically recurring time slots; a temporary memory for recording information relating to each recurring time slot defined by the switch; decoder means for reading in sequence from the temporary memory information relating to each time slot of the system and providing inputs to said time division switch identifying the paths to be gated together during that time slot; a permament memory having recorded therein a series of coded operating instructions for establishing connections via the time division switch; and update circuit means responsive to said permanent memory for recording in the temporary memory equipment addresses corresponding to equipment within the system to be interconnected through the time division switch.
Claim 3
Dependent Claim
36 words
The apparatus of claim 1, wherein said temporary memory comprises a plurality of equal length synchronized recirculating shift registers, each shift register having capacity for at least one information bit pertaining to each recurring time slot.
Claim 4
Dependent Claim
29 words
The apparatus of claim 2, further comprising clock means including a crystal oscillator for advancing the shift registers of the temporary memory and for actuating the time division switch.
Claim 5
Dependent Claim
17 words
The apparatus of claim 1, wherein said permanent memory is a metal oxide semiconductor read only store.
Claim 6
Dependent Claim
31 words
The apparatus of claim 1, wherein said temporary memory includes means for recording therein the identity of at least three equipment addresses to be simultaneously interconnected through one recurring time slot.
Claim 7
Dependent Claim
67 words
The apparatus of claim 1, further comprising at least one class-of-service multiplexer, a plurality of discrete hardwired lines connected to said multiplexer each line being uniquely associated with a particular station to indicate restrictions on the use of that station, and a comparator means for comparing the output of said multiplexer with an output of the permanent memory to determine whether a dialed connection can be established.
Claim 8
Dependent Claim
26 words
The apparatus of claim 1, further comprising line counter means for sequentially accessing equipment addresses for connection with said update means, temporary memory and permanent memory.
Claim 9
Dependent Claim
25 words
The apparatus of claim 1, wherein said line counter means advances to the next sequential address in response to selected inputs from said clock means.
Claim 10
Dependent Claim
94 words
The apparatus of claim 1, further comprising decoder means for determining whether an instruction read out of the permanent memory requires a search of the temporary memory, frame count means for determining when the temporary memory has circulated through a complete cycle, address register means for accessing instructions recorded in the permanent memory, and gate means responsive to the frame count means for inhibiting the address register means from accessing additional instruction until a change in the output of the frame count means indicates that a complete frame of time slots has been searched.
Claim 11
Dependent Claim
18 words
The apparatus of claim 9, wherein the address register means is responsive to selected outputs of the clock.
Claim 12
Dependent Claim
60 words
The apparatus of claim 1, further comprising instruction register means for transitory recording of instructions read out of the permanent memory on a word-by-word basis, decoder means for determining the number of words in an instruction, and instruction counter means responsive to said decoder means for accessing successive portions of said instruction register means for each word of said instruction.
Claim 13
Independent Claim
137 words
A method of operating a telephony system to place a connection in a hold condition and later returning the connection to an active state without dedicating a line attached to the holding station to the held call comprising: recording the addresses of equipment involved in the connection to be held in a temporary memory; recording in said temporary memory in association with said addresses a coded indication that the connection is in a held condition; disestablishing the audio connection between the equipment associated with the addresses recorded in the temporary memory; searching said temporary memory for the information relating to said held connection when it is desired to reestablish the active condition; removing said coded indication from said temporary memory; and re-establishing an audio path between the equipment associated with the addresses recorded in the temporary memory.
Claim 14
Independent Claim
137 words
A method of operating a telephony system to place a connection in a hold condition and later returning the connection to an active state without dedicating a line attached to the holding station to the held call comprising: recording the addresses of equipment involved in the connection to be held in a temporary memory; recording in said temporary memory in association with said addresses a coded indication that the connection is in a held condition; disestablishing the audio connection between the equipment associated with the addresses recorded in the temporary memory; searching said temporary memory for the information relating to said held connection when it is desired to reestablish the active condition; removing said coded indication from said temporary memory; and re-establishing an audio path between the equipment associated with the addresses recorded in the temporary memory.
Claim 15
Dependent Claim
21 words
The method of claim 12, further comprising constantly recirculating the information in said temporary memory through a plurality of shift registers.
Claim 16
Dependent Claim
32 words
The method of claim 12, wherein said audio connection is established by gating audio information through a time division switch to interconnect equipment associated with the addresses recorded in said temporary memory.
Claim 17
Dependent Claim
38 words
The method of claim 12, further comprising indicating that the connection is to be placed in a hold condition by activating a timer to place a station involved in connection in an on-hook condition for a predetermined interval.
Claim 18
Independent Claim
158 words
A method of making time division connections through a branch exchange of a telephony system comprising: entering in a temporary memory in association with each other addresses assigned to parts of the system to be interconnected through the exchange during a recurring time slot; reading information relating to each time slot of the system from the temporary memory in a recurring sequence and thereby continuously identifying the paths to be gated together during a particular time slot; gating together the parts of the system assigned to associAted addresses during a time slot that recurs at a frequency equal to the frequency of recurrance of information in the temporary memory multiplied by a positive integer; sensing changes in the conditions of parts of the system that can be interconnected through common time slots; reading recorded instructions from a permanent memory in response to said conditions; and updating the information contained in the temporary memory in accordance with said instructions.
Claim 19
Independent Claim
158 words
A method of making time division connections through a branch exchange of a telephony system comprising: entering in a temporary memory in association with each other addresses assigned to parts of the system to be interconnected through the exchange during a recurring time slot; reading information relating to each time slot of the system from the temporary memory in a recurring sequence and thereby continuously identifying the paths to be gated together during a particular time slot; gating together the parts of the system assigned to associAted addresses during a time slot that recurs at a frequency equal to the frequency of recurrance of information in the temporary memory multiplied by a positive integer; sensing changes in the conditions of parts of the system that can be interconnected through common time slots; reading recorded instructions from a permanent memory in response to said conditions; and updating the information contained in the temporary memory in accordance with said instructions.
Claim 20
Dependent Claim
37 words
The method of claim 16, further comprising entering in said temporary memory in association with each address an off-hook bit indicating whether the part of the system assigned said address is in an on-hook or off-hook condition.
Claim 21
Dependent Claim
31 words
The method of claim 16, further comprising entering in said temporary memory in association with each time slot an indication of the status of the connection established in that time slot.
Claim 22
Dependent Claim
26 words
The method of claim 16, wherein said changes are sensed by stepping a line counter sequentially through the addresses assigned to said parts of the system.
Claim 23
Dependent Claim
38 words
The method of claim 16, wherein at least three addresses are inserted in association with each other in said temporary memory to establish a connection between at least three parts of the system through a common time slot.
Claim 24
Independent Claim
138 words
A method of making time division connections through a branch exchange of a telephony system comprising: entering in a temporary memory in association with each other addresses assigned to parts of the system to be interconnected during a recurring time slot; constantly causing the information recorded in said temporary memory to recirculate and constantly reading said information out of the temporary memory as it recirculates; gating together the parts of the system assigned to associated addresses during a time slot that recurs at the frequency at which the information in the temporary memory recirculates; sensing changes in the conditions of parts of the system that can be interconnected through common time slots; reading recorded instructions from a permanent memory in response to said conditions; and updating the information contained in the temporary memory in accordance with said instructions.
Claim 25
Independent Claim
138 words
A method of making time division connections through a branch exchange of a telephony system comprising: entering in a temporary memory in association with each other addresses assigned to parts of the system to be interconnected during a recurring time slot; constantly causing the information recorded in said temporary memory to recirculate and constantly reading said information out of the temporary memory as it recirculates; gating together the parts of the system assigned to associated addresses during a time slot that recurs at the frequency at which the information in the temporary memory recirculates; sensing changes in the conditions of parts of the system that can be interconnected through common time slots; reading recorded instructions from a permanent memory in response to said conditions; and updating the information contained in the temporary memory in accordance with said instructions.
Claim 26
Dependent Claim
54 words
The method of claim 21, further comprising determining the number of words in each instruction by decoding the first word of the instruction as it is read out of the permanent memory and entering the words in successive positions of an instruction register as they continue to be read out of the permanent memory.
Claim 27
Dependent Claim
10 words
The method of claim 16, wherein said integer is 1.
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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |