Multi-station telephone switching system

Abstract

A multi-station telephone communication system in which there is designated a master station and several other stations. Each of the stations is capable of communicating with any of a large number of standard telephone lines and non-locking pushbuttons are utilized to select the lines connected to each station. Each station is capable of monitoring the active line on which any of the other stations is communicating. Additionally, the master station is capable of supervising the conversation in any of the other stations by an ASSIST LOOP connection, in which the master station can overhear the conversation, but communicate one way with only one of the parties in the two-way communication. Each station is provided with a turret having panels in which are mounted their respective displays for indicating the active lines which are in communication with the respective turret as well as the lines in active communication with the other stations.

I claim: 
     
       1. For a telephone system in which telephone communication is capable of being established for each telephone station of a plurality of telephone stations over a standard telephone line by directly connecting each telephone station to a selected standard telephone line of a plurality of standard telephone lines, each of said plurality of standard telephone lines capable of being directly connected to each of said plurality of telephone stations, an improvement comprising: a plurality of pairs of contacts, with respective pairs of said contacts being connected with respective ones of said standard telephone lines for allowing said communication;   a plurality of relay coils, with respective ones of said relay coils controlling respective pairs of said contacts to be opened or closed;   a plurality of sets of .Iadd.non-locking .Iaddend.pushbutton .[.switch means.]. .Iadd.switches .Iaddend.with each set of pushbutton .[.switch means .]. .Iadd.switches.Iaddend.connected to respective ones of said telephone stations with respective ones of said pushbutton .[.switch means.]. .Iadd.switches .Iaddend.of said sets of pushbutton .[.switch means.]. .Iadd.switches .Iaddend.corresponding to respective ones of said standard telephone lines and being connected with a respective ones of said relay coils and being depressed for energizing a selected one of said relay coils for closing a corresponding pair of contacts to allow said telephone communication; .[.and.]..Iadd.   an electronic holding circuit for each of said relay coils, said holding circuits being operative to establish a held state after initial energization of the associated relay coil by momentarily depressing the associated pushbutton switch, and   to maintain said corresponding pair of contacts closed while in the held state;     a logic circuit for each station connected to said holding circuits to detect conditions for releasing the held state; .Iaddend.   each of said stations comprising .[.first light display means.]. .Iadd.a set of status lights.Iaddend., connection means connecting corresponding pushbuttons of said sets of pushbutton .[.switch means.]. .Iadd.switches .Iaddend.in each of said stations and to said .[.first light display means.]. .Iadd.status lights .Iaddend.for energizing said .[.first light display means.]. .Iadd.status lights .Iaddend.in each station to display the status of each of said plurality of standard telephone lines in each of said stations,    said station further comprising .[.second light display means.]. .Iadd.an active line indicator separate from said status lights .Iaddend.connected to said pushbutton .[.switch means.]. .Iadd.switches .Iaddend.for identifying the standard telephone line .Iadd.of said plurality of standard telephone lines .Iaddend.that the telephone station is using for said telephone communication. .[.   
     
     
       2.  A system as set forth in claim 1, wherein each of said pushbutton switch means comprises a non-locking depressible pushbutton..]. .[.3. A system as set forth in claim 1, further comprising coder means connected between each pushbutton switch means of each set of said pushbutton means and said second light display means at each station for generating a unique electrical signal corresponding to the selected pushbutton switch 
     
     
        means depressed..]. 4. A system as set forth in claim 1, wherein said .[.second light display means.]. .Iadd.active line indicator .Iaddend.comprises a display area and means connected to said pushbutton .[.switch means.]. .Iadd.switches .Iaddend.for producing a numeral on said display area indicating the standard telephone line which is in active communication. .[.5. A system as set forth in claim 4, further comprising coder means connected to said pushbutton switch means for generating a unique electrical signal corresponding to the selected pushbutton switch means depressed, the output of said coder means being connected to said 
     
     
        second light display means..]. 6. A system as set forth in claim 1, comprising a turret housing a respective set of said plurality of sets of said pushbutton .[.means and said first and second display means.]. .Iadd.switches and status lights, said active line indicator, .Iaddend.said plurality of pairs of contacts and .Iadd.wherein .Iaddend.said plurality of relay coils .[.being.]. .Iadd.is .Iaddend.located remotely from said turret and .Iadd.further comprising .Iaddend.electrical cable means connecting said turret to said plurality of relay coils for carrying electrical signals to control said relay 
     
     
        coils. .[.7.  A turret located at each telephone station of a plurality of telephone stations for use with a switching system, said switching system establishing telephone communication for each telephone station over a standard telephone line by directly connecting each telephone station to a selected standard telephone line of a plurality of standard telephone lines, said switching system comprising a plurality of pairs of contacts being connected with respective ones of said standard telephone lines for allowing said communication; and a plurality of relay coils, with respective ones of said relay coils controlling respective pairs of said contacts to be opened or closed; said turret comprising   a plurality of pushbutton switch means for producing an electrical control signal with respective ones of said pushbutton switch means being connected with a respective one of said relay coils for energizing a selected one of said relay coils for closing a corresponding contact pair to allow said telephone communication along said selected telephone line,   panel means for mounting said plurality of pushbutton switch means, and   first light display means, connection means connected between corresponding pushbutton switch means in each of said turrets and said first light display means for displaying in each turret the status of each of said plurality of standard telephone lines, said turret further comprising second light display means connected to said pushbutton switch means for identifying the standard telephone line that the telephone station is   
     
     
        using during said telephone communication..]. .[.8.  A turret as set forth in claim 7, wherein said turret further comprises a telephone line panel area for housing said pushbutton switch means and said first light display means, a display panel area for housing said second light display means, and a functional panel are for housing functional pushbutton switch means, all of said panel areas being formed in the same plane..]. .[.9. A turret as set forth in claim 7, wherein said plurality of standard telephone lines, said plurality of pairs of contacts and said plurality of relay coils are remotely located from said turret, further comprising cable means connected between said turret and said relay coils for controlling the closing of selected pairs of contacts..]. .[.10. In combination a plurality of telephone stations;   a plurality of standard telephone lines each being connectable to each of said plurality of telephone stations;   a plurality of pairs of contacts, with respective pairs of said contacts being connected with respective ones of said standard telephone lines for allowing telephone communication with said telephone stations;   a plurality of relay coils, with respective ones of said relay coils controlling respective pairs of said contacts to be opened or closed; and   each of said stations comprising a plurality of pushbutton switch means for producing electrical control signals, with each of said pushbutton switch means being connected with a respective one of said relay coils for energizing a selected one of said relay coils for closing a selected contact pair to allow telephone communication along a selected standard telephone line of said plurality of standard telephone lines;   each of said telephone stations comprising display means connected to said pushbutton switch means in each of said telephone stations for identifying which of said other telephone stations are in active telephone communication..]. .[.11. A system as set forth in claim 10, wherein each of said stations comprises a turret, each of said turrets comprising a panel for said plurality of pushbuttons at said station, said panel further comprising a display panel area for said display means..]. .[.12. A system as set forth in claim 11, wherein said display panel area comprises a plurality of turret display areas, each of said turret display areas corresponding to a respective one of said turrets..]. .[.13. A system as set forth in claim 12, wherein said plurality of turret display areas comprises a plurality of windows, each of said window locations corresponding to a respective one of said turrets..]. .[.14. A system as set forth in claim 12, wherein each of said turret display areas comprises means for displaying the telephone line of said plurality of standard telephone lines to which each of said respective turrets is actively connected..]. .[.15. A system as set forth in claim 14, wherein each of said turrets comprises driver means for driving said display means, each of said driver means being controlled by a respective one of said stations to display in each station the status of all other stations, said driver means, controlling said display means to produce an alphanumeric symbol representing the telephone line of said plurality of standard telephone lines to which said respective turret is actively connected..]. .[.16. a system as set forth in claim 15, wherein said alphanumeric symbol   
     
     
        comprises a two-digit decimal base number..]. .[.17.  a system as set forth in claim 16, wherein each station comprises code means connected to respective driver means located in each of said plurality of stations, said code means driving said driver means at each of said stations to simultaneously display at all stations the telephone line of said plurality of standard telephone lines to which said respective turret is actively connected..]. .[.18. A system as set forth in claim 17, wherein said code means comprises a coder, said coder connected to said plurality of pushbutton switch means to produce a two-digit unique code to drive said driver means at each of said stations, said unique code representative of the specific pushbutton switch means and corresponding telephone line selected..]. .[.19. A system as set forth in claim 10, wherein said display means identifies the telephone line of said plurality of standard telephone lines to which each of said other stations is actively connected..]. .[.20. A system as set forth in claim 19, wherein each of said stations comprises a plurality of drive means connected to said pushbutton switch means for driving said display means, each of said driver means being controlled by a respective one of said stations to display in each station the status of said respective one of said stations, said drive means controlling said display means to produce an alphanumeric symbol representing the telephone line of said plurality of standard telephone lines to which each of said respective stations is actively connected..]. .[.21. A system as set forth in claim 20, wherein said alphanumeric symbol comprises a two-digit decimal base number..]. .[.22. A system as set forth in claim 21, wherein each station comprises coder means having a plurality of inputs, with each of said inputs connected to a respective one of said plurality of pushbutton switch means and output means connected to each of said plurality of stations, said coder means driving said driver means at each of said stations to simultaneously display at all stations the telephone line of said plurality of standard telephone lines to which each of said stations is actively connected..]. .[.23. For use with a plurality of standard telephone lines and a plurality of telephone stations; a master telephone station;   each of said plurality of standard telephone lines connectable to each of said plurality of telephone stations and to said master telephone station;   a plurality of pairs of contacts, with respective pairs of said contacts being connected with respective ones of said standard telephone lines for allowing telephone communication with all of said telephone stations;   a plurality of relay coils, with respective ones of said relay coils controlling respective pairs of said contacts to be opened or closed;   each of said telephone stations and said master station comprising a plurality of pushbutton switch means for producing an electrical control signal with each of said pushbutton switch means being connected with a respective one of said relay coils for energizing a selected one of said relay coils for closing a selected contact pair to allow telephone communication along a selected telephone line of said standard telephone lines;   said master station comprising a plurality of display means with respective ones of said plurality of said display means connected to respective ones of said telephone stations for identifying which of said telephone stations are in active telephone communication; and   signaling means connected to each of said telephone stations for providing a request signal displayed on respective display means at said master   
     
     
        telephone station..]. .[.24.  For a telephone system in which telephone communication is capable of being established for each telephone station of a plurality of telephone stations over a standard telephone line by directly connecting each telephone station to a selected standard telephone line of a plurality of standard telephone lines, an improvement comprising each of said telephone stations comprising a network being capable of establishing two-way telephone communication through said network over said standard telephone line;   a master telephone station; said master station comprising an additional network connectable to each of said plurality of telephone stations enabling said master station to have two-way communication with any of said plurality of telephone stations, said master station being connected to hear the communication at any of said telephone stations;   each of said telephone stations comprising blocking means to block the communication received from said master station from being transmitted to said standard telephone line..]. .[.25. The system of claim 24, wherein each of said plurality of telephone stations comprises a transmitter and a receiver, said blocking means being connected to said receiver, and shunt means connected across said receiver, said shunt means normally being operative permitting standard two-way telephone communication through said network at said telephone station over said standard telephone lines..]. .[.26. The system of claim 24, wherein each of said telephone stations comprise a request switch being closed to connect said additional network to a respective telephone station, said master station comprising an answer switch being closed to connect said master station to said additional network..]. .[.27. In combination   a plurality of telephone stations;   a plurality of standard telephone lines being connectable to each of said plurality of telephone stations;   switching means for selectively directly connecting each telephone station to any one of said plurality of telephone lines to permit said communication;   each telephone station comprising a respective plurality of pushbutton switch means connected to said switching means, each of said respective pushbutton means operating said switching means to connect a corresponding selected telephone line to the corresponding telephone station for active communication; and   each of said stations comprising display means connected to said pushbutton switch means in each of said telephone stations for identifying which of the other stations are in active telephone communication..]. .[.28. A system as set forth in claim 22, wherein each of said stations comprises a turret comprising said respective plurality of pushbutton switch means, each of said turrets comprising panel means including a panel for said respective plurality of pushbuttons, said panel means further comprising a display panel area for said display means..]. .[.29. A system as set forth in claim 28, wherein said display panel area comprises a plurality of turret display areas, each of said turret display areas corresponding to a respective one of said turrets..]. .[.30. A system as set forth in claim 29, wherein said plurality of turret display areas comprises a plurality of windows, each of said window locations corresponding to a respective one of said turrets..]. .[.31. A system as set forth in claim 29, wherein each of said turret display areas comprises means for displaying the telephone line of said plurality of standard telephone lines to which each   
     
     
        of said respective turrets is actively connected..]. .[.32.  A system as set forth in claim 31, wherein each of said stations comprises driver means for driving said display means, each of said driver means being controlled by a respective one of said stations to display in each station the status of said respective one of said stations, said driver means controlling said display means to produce an alphanumeric symbol representing the telephone line of said plurality of standard telephone lines to which said respective station is actively connected..]. .[.33. A system as set forth in claim 32, wherein said alphanumeric symbol comprises a two-digit decimal base number..]. .[.34. A system as set forth in claim 33, wherein each station comprises code means connected to respective drivers in each of said plurality of stations, said code means driving said driver means at each of said stations to simultaneously display at all stations the telephone line of said plurality of standard telephone lines to which said respective turret is actively connected..]. .[.35. A system as set forth in claim 34, wherein said code means comprises a coder, said coder connected to said plurality of pushbutton switch means to produce a two-digit unique code to drive said driver means at each of said stations, said unique code representative of the specific pushbutton switch means and corresponding standard telephone line selected..]. .[.36. A system as set forth in claim 27, wherein said display means identifies the telephone line of said plurality of standard telephone lines to which each of said respective stations is actively connected..]. .[.37. A system as set forth in claim 36, wherein each of said stations comprises driver means connected to said pushbutton switch means for driving said display means, each of said driver means being controlled by a respective one of said stations to display in each station the status of said respective one of said stations, said driver means controlling said display means to produce an alphanumeric symbol representing the telephone line of said plurality of standard telephone lines to which said stations are actively connected..]. .[.38. A system as set forth in claim 37, wherein said alphanumeric symbol comprises a two-digit decimal base number..]. .[.39. A system as set forth in claim 38, wherein each station comprises coder means having a plurality of inputs with each of said plurality of inputs connected to a respective one of said plurality of respective pushbutton switch means and output means connected to each of said plurality of stations, said coder means driving said driver means at each of said stations to simultaneously display at all stations the telephone line of said plurality of standard telephone lines to which said station is actively connected..]. .[.40. A system as set forth in claim 27, wherein said display means comprises light generation means for identifying which of said telephone stations is in 
     
     
        active communication..]. .[.41.  For use with a plurality of standard telephone lines, a plurality of telephone stations;   a master telephone station;   each of said plurality of standard telephone lines connectable to each of said plurality of stations and to said master telephone station;   switching means for selectively directly connecting each telephone station to any of said plurality of telephone lines to permit said communications;   each of said stations and said master station comprising a respective plurality of pushbutton switch means connected to said switching means, each of said respective pushbutton means operating said switching means to connect a corresponding selected telephone line to the corresponding telephone station for active communication;   said master station comprising display means connected to said pushbutton switch means in each of said stations for identifying which of said other stations is actively connected to any of said standard telephone lines; and   signaling means connected to each of said stations for providing a request signal displayed at said master station..]. .[.42. A system as set forth in claim 41, wherein said display means of said master station comprises separate display areas corresponding to each of said stations, said request signal being displayed in said display area corresponding to said station providing said request..]. .[.43. A system as set forth in claim 42, wherein said display means comprises means to display a representative code corresponding to the active telephone line to which each of said stations is actively connected, said station providing said request producing a signal to periodically turn the displayed code on and off for signaling the request..]. .[.44. A system as set forth in claim 43, wherein said master station comprises means for establishing a connection between said master station and the station providing the request signal..]. .[.45. A system as set forth in claim 44, wherein the operator as said station providing the request signal is in telephone two-way communication over a standard telephone line with another operator at another telephone location, said master station comprising means connected to said station providing the request signal to establish connection to said two-way communication, said station providing the request signal comprising switching means for enabling said master station to communicate directly with said station providing the request signal and blocking means to prevent the operator at said other location from hearing the communication between said master station and said station providing the   
     
     
        request signal..]. 46. A turret located at each telephone station of a plurality of telephone stations for use with a switching system, said switching system establishing telephone communication for a telephone station over each standard telephone line by directly connecting each telephone station to a selected standard telephone line of a plurality of standard telephone lines, said switching system comprising .Iadd.a holding circuit for each standard telephone line of said plurality of standard telephone lines to establish a held state after momentary actuation, .Iaddend.switching means for selectively directly connecting each telephone station to any one of said plurality of standard telephone lines .Iadd.according to said held state .Iaddend.to permit said communication; .Iadd.and a logic circuit for each station connected to said holding circuits to detect conditions for releasing said held state; .Iaddend. said turret comprising   a plurality of non-locking pushbutton .[.switch means.]. .Iadd.switches .Iaddend.connected to said switching .[.means.]. .Iadd.system.Iaddend., each of said non-locking pushbutton .[.means.]. .Iadd.switches being connected to momentarily actuate one of said holding circuits when depressed for .Iaddend.operating said switching means to connect a corresponding selected standard telephone line to the telephone station corresponding to said turret for active communication;   panel means for mounting said plurality of pushbutton .[.switch means.]. .Iadd.switches.Iaddend.,   .[.first light display means.]. .Iadd.status indicator lights.Iaddend., connection means connected between corresponding pushbutton .[.switch means.]. .Iadd.switches .Iaddend.in each of said turrets and said .[.first light display means.]. .Iadd.status lights .Iaddend.for displaying the status of each of said plurality of standard telephone lines, .[.said turret further comprising second light display means.]. .Iadd. an active line indicator .Iaddend.connected to said non-locking pushbutton .[.switch means.]. .Iadd.switches .Iaddend.for identifying the standard telephone line .Iadd.of said plurality of standard telephone lines .Iaddend.that the   
     
     
        telephone station is using during said telephone communication. 47. A turret as set forth in claim 46, wherein said plurality of standard telephone lines.[., said plurality of pairs of contacts.]. and said switching .[.means.]. .Iadd.system .Iaddend.are remotely located from said turret.[., further comprising cable means connected between said turret 
     
     
        and said switching means.].. .[.48.  For a telephone system in which telephone communication is established for each telephone station of a pluraity of telephone stations over a standard telephone line by directly connecting each telephone station to a selected standard telephone line of a plurality of standard telephone lines, each of said plurality of standard telephone lines capable of being directly connected to each of said plurality of telephone stations, an improvement comprising switching means for selectively directly connecting said one telephone station to any one of said plurality of standard telephone lines to permit said communication;   each of said telephone stations comprising a plurality of pushbutton switch means connected to said switching means, each of said pushbutton means operating said switching means to connect a corresponding selected telephone line to said one station for active communication;   said plurality of standard telephone lines and said switching means being remotely located from said plurality of stations;   each of said telephone stations comprising display means connected to said pushbutton switch means in all of said telephone stations for identifying which of said separate telephone lines is connected with which of said stations for active communication; and   electrical cable means connected between each of said stations and said   
     
     
        switching means..]. 49. For a telephone system in which each telephone station of a plurality of telephone stations can communicate over a standard telephone line by directly connecting each telephone station to a selected standard telephone line of a plurality of standard telephone lines, each of said plurality of standard telephone lines capable of being directly connected to each of said plurality of telephone stations, an improvement comprising, switching means for selectively directly connecting each telephone station to any one of said plurality of telephone lines to permit said communication;   each of said stations comprising a plurality of nonlocking .Iadd.momentary contact .Iaddend.pushbutton .[.switch means.]. .Iadd.switches .Iaddend.connected to said switching means to connect a corresponding selected telephone line to each of said stations, for active communication; .Iadd.   said switching means including a holding circuit for each standard telephone line of said plurality of standard telephone lines, said holding circuits being coupled to said pushbutton switches,   being operative to establish a held state after momentary actuation of a pushbutton switch to indicate which pushbutton at which station was actuated, and   being operative to connect a selected station to a selected one of said standard telephone lines according to said held state;   each of said stations comprising .[.first light display means.]. .Iadd.status indicator lights.Iaddend., connection means for connecting corresponding ones of said push button switch means in each of said stations to said .[.first light display means.]. .Iadd.status indicator lights .Iaddend.for displaying the status of each of said plurality of standard telephone lines .[.and second light display means.]. .Iadd.an active line indicator for each of said stations separate from said status lights and .Iaddend.connected to said nonlocking .[.pushbuttons.]. .Iadd.pushbutton switches and said holding circuits .Iaddend.for identifying which telephone line .Iadd.of the plurality of lines .Iaddend.the station is using for active telephone communication .Iadd.according to a held state of said holding circuits; and   a logic circuit for each station connected to said holding circuits to   
     
     
        detect conditions releasing the held state.Iaddend.. .Iadd. 50.  The combination according to claim 1, 46 or 49 further including a conference pushbutton and line release pushbutton and wherein said logic circuit releases any holding circuit having a held state associated with a particular station whenever another pushbutton at said associated station is momentarily depressed unless done in combination with actuation of said conference pushbutton or   whenever said release pushbutton at said associated station is actuated.   
     
     
        .Iaddend..Iadd. 51.  The combination according to claim 46 or 49 further including active line indicators at each station for each other station in the system, and wherein said active line indicators at each station indicate the active line to which each telephone in the system is connected. .Iaddend..Iadd. 52. The combination according to claim 51 wherein said active line indicators are illuminated numeric indicators. .Iaddend.