[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

EP0252969A1 - Dispositif d'intercommunications telephoniques - Google Patents

Dispositif d'intercommunications telephoniques

Info

Publication number
EP0252969A1
EP0252969A1 EP87900842A EP87900842A EP0252969A1 EP 0252969 A1 EP0252969 A1 EP 0252969A1 EP 87900842 A EP87900842 A EP 87900842A EP 87900842 A EP87900842 A EP 87900842A EP 0252969 A1 EP0252969 A1 EP 0252969A1
Authority
EP
European Patent Office
Prior art keywords
switch
conductors
pair
condition
telephone
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP87900842A
Other languages
German (de)
English (en)
Inventor
William Albert Kirby
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ACHIEVERS Co Inc
Original Assignee
ACHIEVERS Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ACHIEVERS Co Inc filed Critical ACHIEVERS Co Inc
Publication of EP0252969A1 publication Critical patent/EP0252969A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/02—Arrangements for interconnection not involving centralised switching involving a common line for all parties
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/71—Substation extension arrangements
    • H04M1/715—Substation extension arrangements using two or more extensions per line

Definitions

  • This invention relates to a telephone intercom apparatus.
  • Telephone systems installed in domestic households are usually provided with four wires, looped around the house to the various outlet locations. These wires are conventionally termed and referred to in this specification as the M, N, P and Q wires. Only two of these wires, M and N, are connected to the external telephone wires. Normally, the other two P, Q are redundant.
  • Bartelink U.S. Patent 4,485,273 an intercom system is shown which uses a manual switch to change from the external to the intercom wires. This arrangement, however, prevents normal use of the telephone if the switch is left in the intercom position. Bartelink proposes to avoid this by providing a relay to connect the handset to the external wires when the handset of the telephone is replaced but this arrangement has the disadvantage that as soon as the handset is picked up in response to the ringing of an external call, the switch
  • SUBSTITUTESHEET reverts to the intercom position, thereby interrupting the incoming call.
  • an intercom device for use with a telephone system having a plurality of telephones interconnected to one another and to an external line by a multiple conductor cable, each of said telephones having a first switch associated therewith to control enabling of said telephone, said device comprising a first pair of conductors to be connected to the conductors of said cable connected to said external line, a second pair of conductors to be connected with a pair of conductors of said cable not connected to said external line, and a third pair of conductors to be connected to a respective one of said telephones and to opposite sides of said first switch, a mode selection switch operable in either a first or second condition to connect said third pair of conductors with said first and second pair of conductors respectively, biasing means to bias said switch to said first condition, switch operating means to condition said mode selection switch to said second condition and holding means associated with said second pair of conductors to maintain said mode selection switch in said second condition, said holding means being disabled upon disablement of said telephone by said first switch to permit
  • figure 1 is a schematic representation of a domestic installation equipped with an intercom
  • figure 2 is an alternative embodiment of the intercom device shown in figure 1
  • figure 3 is yet a further embodiment of the intercom device shown in figure 1.
  • the cable (16) is formed from a first pair of conductors (18), (20), and a second pair of conductors (22), (24).
  • the cable (16) is looped through the building in which the telephone system is to be installed to terminate at jacks (26) located at convenient locations.
  • Each of the jacks (26) is of conventional structure having a socket (28).
  • An intercom control circuit box (32) is connected by a plug 30 to each of the jacks at which an intercom facility is required.
  • the box (32) also has a socket (34) of similar configuration to the socket (28) to receive a plug (36) associated with a telephone handset (38).
  • Each telephone handset (38) is connected to the box (32) through a two-conductor cable (40) that terminates at the plug (36).
  • the telephone (38) has a handset (42) containing a mouthpiece (44) and earpiece (46) and engages a cradle switch (48) whenever the handset (42) is replaced on the telephone.
  • the switch (48) therefore controls enabling of the telephone.
  • the control circuit (50) includes a pair of conductors (52), (54) that are connected through the jack (26) to the conductors (18), (20) of the cable (16).
  • the conductors (54) terminate at terminals (56), (58) respectively, of a two-pole relay (60) that selects the mode of operation of the control intercom circuit 50.
  • Contacts (62), (64) in the relay (60) are connected to a pair of conductors (66), (68) which terminate at the socket (34) to be connected to the conductors of cable (40).
  • Relay (60) is biased to the position shown in figure 1 so that whenever the relay operating circuit is open, the conductors (66), (68) are connected to the external line through the conductors (52), (54).
  • the circuit (50) includes a second pair of conductors (70), (72) that are connected through the jack (26) to the conductors (22), (24) of cable (16) and extend to a second pair of poles (74), (76) respectively, of the relay (60).
  • Relay (60) is operated by a coil (80) in the conductor (72).
  • a capacitor (78) is incorporated into the conductor (78) prior to the coil (80) and a second capacitor (82) is connected in parallel to the coil (80).
  • Power for the relay (80) is provided by a battery (84) connected between the conductors (70), (72) and control for the relay is provided by a switch (86) also connected across the conductors (72), (74) in parallel to the relay (60) .
  • a signalling function is provided in the intercom circuit (50) by a power source (88) connected in series with a pushbutton switch (90) which is connected across the conductors (70), (72) on the opposite side of the capacitor (78) to the relay coil (80).
  • a DC buzzer (92) is also connected across the conductors (70, (72) so that a DC voltage applied across those conductors will activate the buzzer.
  • the pushbutton (86) In operation with the handset (42) at rest on the cradle, the pushbutton (86) is normally open, as is the pushbutton (90).
  • the cradle switch (48) is also open so that the circuit to the relay coil (80) is interrupted and the relay reverts to the position shown in which it connects the conductors (40) to the conductors (58), (56) and thus to the external lines (12), (14). In this position the telephone can be used in the normal manner as lifting the handset (42) from the cradle will not complete a circuit that will energize the coil (80). In this way, external calls can be made or received.
  • the handset is lifted to close the switch (48) and the switch (86) is closed so that the circuit from the battery (84) through the coil (80) is completed.
  • This causes the relay (60) to move to a position in which the contacts (62), (64) make with the conductors (74), (76) to connect the conductors (40) with the conductors (22), (24).
  • the switch (86) is released, the relay is held in the intercom position by the closed circuit provided by the switch (48).
  • the DC voltage applied by the battery (84) is effective to hold the relay closed until the circuit is once again opened by opening of the cradle switch (48).
  • the pushbutton (90) is depressed to complete the circuit from the battery (88) across the conductors (70), (72). This impresses a DC voltage onto the coductors (70), (72) which is also impressed on the corresponding conductors of the other circuits (50). Thus, the buzzer (92) in each of the intercom boxes (32) will sound.
  • the respective handset is lifted to close the cradle switch (48) and the pushbutton (86) depressed so that the relay (60) connects the cable (40) to the conductors (22), (24). In this way conversation can be carried out amongst the handsets.
  • the switch upon replacement of a handset, the switch is opened which breaks the circuit through the coil (80) and so causes the relay to revert to the position shown in figure 1 at which the conductors (40) are connected through conductors (56), (58) to the external conductors (12), (14).
  • the telephone system upon return of the handset (42) to the telephone, or indeed simple depression of the switch (48), the telephone system is returned to a condition in which it can be used in a conventional manner to receive incoming or make outgoing calls.
  • the circuit In the event that an incoming call is received and the call is to be transferred to another handset, the circuit provides for a ring signal to be generated in the other handsets whilst the external call is being received. This is because the capacitor (78) effectively isolates the signalling circuit from the relay operating circuit so that closing of the switch (90) will not operate the relay. Thus, with the handset (42) removed from the cradle to receive an external call, the switch (90) may be depressed to complete the circuit through the buzzer (92) in the other handsets and thereby attract the attention of another party. The provision of the capacitor (78) ensures that the depression of the button (90) will not activate the relay and interrupt the external call.
  • the circuit is always reconditioned to receive incoming calls upon completion of the use of the intercom. This is achieved by placing the relay hold circuit in series with the switch (48) with a second switch (86) in parallel. Moreover, as noted above, a signal can be generated on the other handsets even when the normal external call is being received. The signal used is a DC signal as opposed to an AC signal. This results in considerable simplification and at the same time does not interfere with the normal voice communications between adjacent handsets.
  • FIG. 1 A further embodiment of the circuit shown figure 1 is shown in figure 2.
  • an opto-coupler (100) is used to control current flow through the coil (80) to avoid the need to match the impedence of the coil (80) with that of the telephone handset (42).
  • the switch (86) when the switch (86) is depressed, current flows from the battery (84) to switch on the opto-coupler (100) and turn on a transistor (102).
  • the relay coil (80) is placed in series with the transistor (102) so that upon the transister being turned on, the relay coil (80) is operated to move the relay to the intercom position.
  • the relay (60a) returns to the position in which the conductors (40a) are connected to the conductors (70), (72).
  • the capacitor (82a) and a similar capacitor (104) included in the conductor (70a) permit transmission of the voice frequency voltages to pass along the conductors (70), (72) without rectification by the opto-coupler (100).
  • the capacitors (82a) and (104) also isolate the relay operating circuit from the signalling circuit to ensure tht the relay (60a) does not operate when buzzers (90a) are operated.
  • a current-limiting resistor (106) is included in the feed from the conductor (70).
  • a light (108) is included in parallel with the relay coil (80a) to indicate when the intercom is in use.
  • FIG 3 The arrangement shown in figure 3 is similar to that of figure 2 with like components identified by the same reference numeral as in figure 1 but a suffix 'b' added for clarity.
  • the DC buzzer (92b) is inhibited when the call is initiated from the associated intercom device (32b).
  • the single pole switch (90) in figure 1 is replaced by a double pole switch (92b) that, in its normal position, makes the circuit that includes the buzzer (92b).
  • the branch of the circuit including the buzzer in the intercom station is isolated, although a DC voltage is still applied across the conductors (70), (72).
  • a ring detector (110) is included in the conductors (54), (52) to generate a voice frequency tone in the conductors (70), (72) when a ring tone is received on the lines (52), (54). In this way the user of the handset in the intercom mode will be aware of an incoming call on the external lines (12) and (14).

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)

Abstract

Le dispositif utilise une paire de conducteurs connectés entre des téléphones (38) mais non à une ligne extérieure (12, 14). Le dispositif d'intercommunication raccorde le téléphone (38) à la ligne extérieure (12, 14) ou aux autres téléphones par un sélecteur de mode (60) commandé par un relais (60). Ce dernier est excité par un commutateur manuel (86) relié en parallèle au téléphone pour aboutir au mode d'intercommunication et est maintenu en mode d'intercommunication par un circuit de maintien qui comporte le commutateur (48) associé au combiné téléphonique. La remise en place du combiné (42) ouvre le circuit de maintien et provoque le retour du sélecteur de mode (60) aux lignes extérieures (12, 14). Le circuit de maintien ne fonctionne qu'à partir du moment où le sélecteur de mode a été à nouveau remis sur la position d'intercommunication par l'actionnement du commutateur manuel (86).
EP87900842A 1986-01-13 1987-01-13 Dispositif d'intercommunications telephoniques Withdrawn EP0252969A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8600712 1986-01-13
GB868600712A GB8600712D0 (en) 1986-01-13 1986-01-13 Telephone intercom device

Publications (1)

Publication Number Publication Date
EP0252969A1 true EP0252969A1 (fr) 1988-01-20

Family

ID=10591294

Family Applications (2)

Application Number Title Priority Date Filing Date
EP87900842A Withdrawn EP0252969A1 (fr) 1986-01-13 1987-01-13 Dispositif d'intercommunications telephoniques
EP87300267A Withdrawn EP0235883A1 (fr) 1986-01-13 1987-01-13 Dispositif d'intercommunication téléphonique

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP87300267A Withdrawn EP0235883A1 (fr) 1986-01-13 1987-01-13 Dispositif d'intercommunication téléphonique

Country Status (4)

Country Link
EP (2) EP0252969A1 (fr)
CA (1) CA1307602C (fr)
GB (1) GB8600712D0 (fr)
WO (1) WO1987004312A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1226312B (it) * 1988-07-26 1990-12-27 Italtel Telematica Sistema di telefoni intercomunicanti su linea bifilare.
FR2679401B1 (fr) * 1991-07-16 1993-11-05 Paul Bloch Systeme d'intercommunication residentiel.
IL104668A (en) * 1993-02-09 1996-03-31 Avish Jacob Weiner Telephone system and connector for it

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4196317A (en) * 1978-01-20 1980-04-01 Bartelink E H B Telephone intercom system
US4485273A (en) * 1982-09-23 1984-11-27 Bartelink E H B Intercom adapter for telephones
US4588861A (en) * 1984-07-25 1986-05-13 Teich Rudor M Telephone intercom system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8704312A1 *

Also Published As

Publication number Publication date
EP0235883A1 (fr) 1987-09-09
GB8600712D0 (en) 1986-02-19
CA1307602C (fr) 1992-09-15
WO1987004312A1 (fr) 1987-07-16

Similar Documents

Publication Publication Date Title
US6744786B1 (en) Method and apparatus for using telephone house wiring for voice/data network
US4850012A (en) Automated access facilities for use with key telephone systems
US4408102A (en) Two-wire exchange telephone system
US5321742A (en) Entry door answering telephone system
US4754476A (en) Premises page/intercom system utilizing telephone set component
US4588864A (en) Small key telephone system
EP0252969A1 (fr) Dispositif d'intercommunications telephoniques
US4868847A (en) Telephone intercom device
JPH01276988A (ja) 構内電話交換機
US3435151A (en) Arrangement of branched telephone subsets
US4175216A (en) Intercom calling apparatus in a key telephone system
JP2961849B2 (ja) 構内交換システム
US4819262A (en) Electronic gating control for manual telephone switchboard
JPS62200852A (ja) ボタン電話装置の停電電話機
JP2731527B2 (ja) 電話交換システムの増設用子器
JP2637086B2 (ja) 電話システム
US6272210B1 (en) Communication system between local area network stations
JP2793202B2 (ja) 電話機
JPS6328554B2 (fr)
JP2947476B2 (ja) 電話交換システム
JPH046315Y2 (fr)
CA2019166A1 (fr) Appareil telephonique pouvant etre connecte a plusieurs lignes telephoniques
JPH0313798B2 (fr)
KR850002664Y1 (ko) 외부전원 공급장치가 필요없는 온 후크 다이얼막 전화장치
KR840002134B1 (ko) 자동식 전화기 증설장치

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19871015

RIN1 Information on inventor provided before grant (corrected)

Inventor name: KIRBY, WILLIAM, ALBERT