GB2225514A - A switching apparatus for data and audiocommunication - Google Patents
A switching apparatus for data and audiocommunication Download PDFInfo
- Publication number
- GB2225514A GB2225514A GB8923976A GB8923976A GB2225514A GB 2225514 A GB2225514 A GB 2225514A GB 8923976 A GB8923976 A GB 8923976A GB 8923976 A GB8923976 A GB 8923976A GB 2225514 A GB2225514 A GB 2225514A
- Authority
- GB
- United Kingdom
- Prior art keywords
- switching apparatus
- data
- base station
- audio
- output
- 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- Withdrawn
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
- B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators
- B66B5/0006—Monitoring devices or performance analysers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/60—Systems for communication between relatively movable stations, e.g. for communication with lift
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
- H04M11/04—Telephonic communication systems specially adapted for combination with other electrical systems with alarm systems, e.g. fire, police or burglar alarm systems
Abstract
A switching apparatus is provided having input terminals which are arranged to be connected to a lift monitor (24, 25, 26) and a telephone (27, 28, 29) in a lift, and an output 20 which is arranged to be connected with a communication line to a central base station through a receiver modem. The switching apparatus comprises an audiotransfer means (31) and data transfer means (33). A data processing means (30) connected with the audio transfer means and data transfer means is arranged to transfer either an audio or data signal to the base station based on a preprogrammed priority system or a command signal from the base station. <IMAGE>
Description
A SWITCHING APPARATUS FOR DATA AND AUDIOCOMMUNICATION
TECHNICAL FIELD
The present invention relates to e switching apparatus which permits transmission of data and voice signals between remote sites and a central base station.
BACXROUND OF INVENTION The present invention is particularly applicable to elevator car monitoring systems such as those in which elevator cars in a number of buildings are monitored by the utilization of sensors located in each elevator car which transmit sensed information to a monitor in each building.
The parameters selected for monitoring are chosen according to their importance in evaluating the operational condition of the elevator system. Typical sensors include an alarm button sensor, a door fully opened sensor, a floor tone sensor and a brake safety circuit complete sensor.
These sensors produce signals which may be multiplexed into a transmitter for transmittal to a local office, a central service center or other information terminals which monitor the status of the sensed parameters.
Upon receiving a signal indicating an abnormal condition, control personnel at the local office or central service centre may diagnose the operational condition of the system by noting the presence or absence of abnormal conditions. The accuracy of the diagnosis depends upon the amount of information received.
The presence of an abnormal condition in some instances may also result in an emergency condition in which a person is trapped within an inoperative elevator car.
In such circumstances, the owner of the building in which the inoperative elevator car is located must telephone a service man and report his version of whatever information he may have received concerning the nature of the inoperative condition. Such a situation is undesirable and an inefficient form of receiving the necessary information to correct the problem causing the inoperative condition.
Some elevator systems provide a back up to the monitoring of the sensed parameters by incorporating an emergency phone within the elevator car. A person trapped within the elevator car is able to speak directly with the central service center or local office by provision of an exclusive communication line between the telephone in the elevator care and the central service center or local office as the case may be. Such a system is deficient in that it requires separate communication lines for data and voice communication with resultant additional costs.
SUMMARY OF THE ZNTI0N According to the present invention, there is provided a switching apparatus for a communication system comprising: an output arranged to be connected with an external communication line connected with a base station; an audio transfer means arranged to receive an audio signal sent from a source remote from the switching apparatus and when in use operable to transfer the audio signal through the output for transmission to the base station; a data transfer means arranged to receive a data signal sent from a source remote from the switching apparatus and when in use operable to transfer the data signal through the output for transmission to the base station; a data processing means connected with the audio transfer means and data transfer means and when in use operable to connect either the audio transfer means or the data transfer means with the output; a line status means which is arranged to be connected with the output for indicating whether a data or audio signal is being transferred to the output; a receiver status means arranged to be connected with the output òr indicating if the base station receiver is engaged; a receiver access means connectable with the output for dialling the base station receiver.
Preferably, the data processing means is arranged to receive the data signal from a source remote from the switching apparatus and transfer the data signal to the data transfer moans.
The data processing means preferably is arranged to be operable by a signal sent from the base station to connect either the audio transfer means or the data transfer means to the output.
Preferably, the line status means is cnnn*ntfl with the data processing means.
The receiver status means is also preferably connected with the data processing means.
The receiver access means preferably is also connected to the data processing means.
According tO a preferred form of the present invention, the line status means comprises a looped line detector.
According to an embodiment of the present invention, the receiver status means comprises a ring detector.
According to a further embodiment of the present invention, the receiver access means comprises a gyrator circuit.
According to e further preferred embodiment, the data transfer means comprises a modem and a dial tone modulator frequency stage (DTMF).
It is proferr: that the data transfer means be coupled with the receiver access means4
The audio transfer apparatus preferably is arranged to receive the audio signal from one or more remote telephones located in one or more respective elevator cars.
The audio transfer apparatus may comprise one or more internal telephone lines connected in parallel.
The ur eacn telephone preferably is arranged to be connected to connection terminals corresponding to the or each respective internal telephone line.
The audio transfer apparatus may comprise audio switching means which is arranged to connect an internal telephone line to the output.
The data processing means referably ii connected to the audio switching means.
Xt is preferred that the audio switching means comprise one or more telephone select relays depending on the number of telephones, and a fall back relay.
The output preferably comprises an internal communication line.
It is preferred that the fall back relay be arranged to connect one or more internal telephone lines in parallel to the internal communication line.
The data processing means is preferably arranged to be able to be connected with a diagnostic monitor for testing purposes.
The data processing means prerably in Arrtned to receive a control audio signal from the or each remote telephone.
The data processing means preferably comprises display switches indicating the status of predetermined parameters of the switching apparatus.
The data processing means may be a mlcroprocessor.
According to the present invention the is also provided a remote monitoring system comprising a monitor and a telephone, both connected to a switching apparatus at a remote site, the switching apparatus being arranged to be connected with a communication line to a central base station through a receiver modem, the switching apparatus being arranged to communicate either a data signal received from the monitor or an audio signal received from the telephone, along the communication line to the receiver modem for processing by a central computer at the base station.
Preferably the base station central computer is arranged to operate the switching apparatus to transfer either the data signal or the audio signal to the receiver modem.
The switching apparatus may be the same as described in any preceding embodiment.
According to a preferred embodiment of the present invention, the remote site is o building and the monitor is used to sense predetermined parameters relating to the status of an elevator car and the telephone is located in the elevator car.
Preferably, the telephone is en auto-dialling telephone.
Preferably, an alarm switch is located in the elevator car and is connected with the switching apparatus through the monitor.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which:
Figure 1 which shows a remote elevator monitoring system; and
Figure 2 shows the switching apparatus of Figure 1.
DETATLEb DESCRIPTION OF THE PREFERRED EMBODIMENTS
The system shown in Figure 1 shows a typical remote site 1, which may be a building having one or more elevator cars, 8 base station 2 normally located in another building and an interconnecting public switched telephone network 3 comprising a single communication line.
At the remote site, each elevator car has data sensors 14 and auto-dial telephones 15. Each data sensor 14 is connected by communication cabling to a monitor 16 which is connected in turn to 8 switching apparatus 17.
The telephones 15 are connected directly to the switching apparatus 17 through individual telephone lines.
The switching apparatus 17 is connected to the public switched telephone network through a single communication line and by a command sequence originating from the central base station computer 18 ie arranged to switch either data signals originating from data sensor 14 or audio signals originating from telephones 15 for transmission through the single communication line of the public switched telephone network to one of a series of modems 19 at the central base station 12.
The modems 19 are connected with the central base station computer 18, a base phone 20 and an after hours switch 21.
The monitor 16 of the above described system is arranged to continuously monitor the sensors 14 for requests to send data. A comparison is made in the monitor between received and stored data and if an abnormal condition is determined, tho switching apparatus is arranged to transfer data relating to the abnormal condition through the public switched telephone network to the central base station.
In addition, persons trapped within an inoperative elevator car by operation of a switch associated with the relevant auto-dialling telephone, may initiate a voice connection with the switching apparatus which will then provide a voice communication connection with the central base station through the public switched telephone network.
The switching apparatus can be made to do this automatically, by giving voice transmission priority over data transmission, or can do this once data transmission has ceased.
The central base station is also able to control the switching operation of the switching apparatus by the transmission of a control signal to the switching apparatus, thus switching between data and voice transmission can be made as frequently and as often as required without the switching apparatus havtng to disengage and re-engage the communication line and the central base station modem connected thereto. The system described also provides unrestricted length calls between the auto-dialling telephones and the central base station.
SWITCHING APPARATUS
The switching apparatus 17 will now be described in more detail with reference to Figure 2.
The switching apparatus consists of a number of input terminals and an output terminal 20 which is arranged to be connected with a communication line which may be part of a public switched telephone network referred to above.
The input terminals comprise AC and DC inputs 21 and 22, a monitor link terminal 24, diagnostic monitor terminal.
25, telephone Connect line terminals 26 and telephone terminals 27, 28 and 29 for connection to three telephones (in this particular embodiment).
The 12 volt AC and DC terminals 21 and 22 are connected with an internal power supply 23 which provides power to the microprocessor 30.
Input terminals 24, 25 and 26 are also connected as inputs to the microprocessor circuits while the telephone inputs 27, 28 and 29 are connected through internal switching circuitry 31 which for convenience will generically be called an "audio transfer circuit".
The audio transfer circuit is connected in parallel across an output line 32 and dependlnq on which relays in the audio transfer are operated one or more telephones will be connected across the output line 32.
With regard to the microprocessor 30, this is connected to a modem and DTMF stage (dial tone modulation frequency stave) 33 which enables data to be sent through the output line 32 and the public switched telephone network through the central base station.
The microprocessor 30 is also connected to display switches 34 to permit the status of the predetermined parameters to be established by a visual inspection of the switching apparatus.
The modem and DTXs stage 23 is coupled with circuitry 35 which for convenience has been called "receiver access circuitry". This incorporates a gyrator circuit 36 and assooiatea data relay 37 and fl P.iR rAlay 3R.
The receiver access circuit is connected to the output line 32 when the seize relay circuit 3B is activated.
A ring detector and looped line detector 39 is connected across the output line 32 and its function and the function of all the other components of the switching apparatus previously mentioned will now be described when in operation.
During normal elevator car operation, each elevator car telephone is disconnected from the public switched telephone network, by a separate relay in each telephone. When an alarm condition occurs, if a person is trapped in an lzvator car, the alarm button can be depressed to send a data signal to the associated monitor which reports the event to the switching apparatus through terminal 24. The pressing of the alarm button also prompts the phone in the lift to attempt an automatic dial out as in fall back mode, which is described later. When the alarm signal is received by the mleroprocessor 30, via terminal 24, the microprocessor 30 interrogates the ring detector and loop line detector 39 in order to establish whether the alarm signal can be sent to the central base station.
The microprocessor 30, through the line detector 39, checks the status of the line between the switching apparatus and the base station to see if it is already busy. If it is not busy, the receiver access circuit is activated to dial the number of a modem at the base station.
The microprocessor then interrogates the ring detector and looped line detector 39 to see if a ring is indicated.
Once the modem 33 senses a carrier from the free modem at the base station, the nicroprocessor 30 sends the alarm signal to the modem and DtMF stage 33 before transmission through the output line 32 through the communication network to the modem at the base station.
The base station interrogates the switch and having elicited the alarm signal, including the unique identity of the relevant lift and lift site, sends the signal to the microprocessor 30 to order the switching apparatus to make a voice connection to the relevant lift telephone.
The switching apparatus then returns a |connect' signal to the relevant telephone via a relay indicating that it should seite the (disconnected line) keeping the sieze relay circuit 38 closed and that it should behave as though a connection had been made. The microprocessor 30 also closes the appropriats telephone line relay 41, 42 or 43 and in addition closes the fall back relay 40.
The switching apparatus continues to monitor the communication line of the public switched telephone line network for the establishment of a carrier i,e. a signal to the microprocessor 30 indicating that more data is to be sent to the central base station or until the expiry of preprogrammed timeouts or a phone hangup at the central base station. When either of these conditions occur, the microprocessor 30 will lift the relevant phone relays.
Whilst the 'connect line is asserted for the relevant telephone's line the microprocessor 30 monitors for answer or keep alive tone sequences from the central base station.
Upon detection of a modem carrier, the switching apparatus disconnects the lift phone and re-establishes data communications with the central base station which may then request a voice connection for transmission of audio signals or continue to receive data in the form of data signals.
FALL BACK MODE
Fall back mode is assumed to be a very rare occurence which is due to equipment faults, emergency power supply failures or similar. In a fall back mode, the switching apparatus is forced to switch off any data communication with the base station and all lift phones are connected in parallel (in the on hook state) to the communication line of the public switched telephone network.
A lift occupant may initiate 'call out' by pressing the lift alarm button.
The relevant telephone will thsn test for a fro line and will then proceed to dial a pre-programmed base station number once the line is available.
Once a successful connection is made with the central base station, the lift phone receives a positive DTMF acknowledgement from the central base station resulting in cancellation of the rat@@ sequence. The poroon in the lift ia then free to talk to a person in the central base station until a disconnect tone is received from the base station or until after 60 seconds unless a keep alive tone is received. This latter tone resets the time out for a further and successive period of 60 seconds.
DIAL STRATEGY
The switching apparatus potentially supports three pairs of phone numbers stored in the microprocessor 30. The first number in the pair is used to establish a data link to the central base station (with digital switch over to voice). The second number is used when the call to the f, st number fails after c attempts It provides a voice only link.
The primary pair is stored in non-volatile memory and it is the normal first choice of the data as defined by the 'window' parameter.
This is a time window that allows selection of the secondary set of numbers during a configurable daily time window.
The secondary pair is stored in non volatile memory and is the second choice of the dialer aa determined by the window definitions.
The tertiary pair is stored in the volatile memory, It is passed to the switching apparatus by the central base station during a digital call and may only be used for a single dial out session before being discarded. This allows dynamic call re-routing as a last resort.
The order of priority is
1. tertiary set when down loaded
2. secondary set when secondary window open
3. primary set when secondery window not open.
The preferred embodiment of the present invention as previously described relates to a monitoring system for elevator cars. The present invention however is not limited to this application alone and may be applied to any system which requires monitoring such as a security system.
Claims (26)
1. A switching apparatus for a communication system comprising: an output (20), (32) arranged to be connected with an external communication line connected with a base station; an audio transfer means (31) arranged to receive an audio signal sent from a source remote from the switching apparatus and when in use operable to transfer the audio signal through the output (20), (32) for transmission to the base station; a data transfer means (33) arranged to receive a data signal sent from a source remote from the switching apparatus and when in use operable to transfer the data signal through the output (20), (32) for transmission to the base station; a data processing means (30) connected with the audio transfer means (31) and data transfer means (33) and when in use operable to connect either the audio transfer means (31) or the data transfer means (33) with the output (20), (32); a line status means (39) which is arranged to be connected with the output for indicating whether a data or audio signal is being transferrea to the output (20), (32); a receiver status means (39) arranged to be connected with the output (20), (32) for indicating if the base station receiver is engagedi a receiver access means (35) connectable with the output for dialling the base station receiver.
2, A switching apparatus according to claim ls wherein the data processing means (30) is arranged to receive the data signal from a source remote from the switching apparatus and transfer the data signal to the data transfer means (33).
3. A switching apparatus according to either claim 1 or 2, wherein the data processing means (30) is arranged to be operable by a signal scot from the base station to connect either the audio transfer means (31) or the data transfer means (33) to the output.
4. A switching apparatus according to any preceding claim, wherein the line status means (39) is connected with the data processing means (30),
5. A switching apparatus according to any preceding claim, wherein the receiver status means (39) is connected with the data processing means (30).
6. A switching apparatus according to any preceding claim, wherein the receiver access means (35) is connected to the data processing means (30).
7. A switching apparatus according to any preceding claim, wherein the line status means (39) comprises a looped line detector.
8. A switching apparatus according to any preceding claim, wherein the receiver status means (39) comprises a ring detector.
9. A switching apparatus according to any preceding claim, wherein the receivor access :ans (35) comprlRbs d gyrator circuit (36), (37), (38).
1O, A switching apparatus according to any preceding claim, wherein the data transfer means (33) comprises a modem and a dial tone modulator fequency stage.
11. A switching apparatus according to any preceding claim, wherein the data transfer means (33) is coupled with the receiver access means (35).
12. A switching apparatus according to any preceding claim, wherein the audio transfer means (31) is arranged to receive the audio signal from one or more remote telephones located in one or more respective elevator car,
13 A switching apparatus according to any preceding claim, wherein the audio transfer means (31) oomprigos one or more internal telephone lines connected in parallel.
14. A switching apparatus according to claim 13, wherein the or each telephone preferrably is arranged to be connected to connection terminals (27), (28), (29) corresponding to the or each respective internal telephone line.
15. A sswttCning apparatus according to claim 14, wherein the audio transfer means comprises audio switching means (40), (41), (42), (43) which is arranged to connect an internal telephone line to the output.
16. A switching apparatus according to claim 15, wherein the data processing means (30) is connected to the audio switching means (40), (41), (42), (43).
17. A switching apparatus according to claim 15, wherein the audio switching means (40), (41), (42), (43) comprises one or more telephone select relays (41), (42), (43) depending on the number of telephones, and a fall back relay (40).
18. A switching apparatus according to any preceding claim, wherein the output (20), (32) comprises an internal communication line (32).
19. A switching apparatus according to claim 18, when appended to claim 17, wherein the fall back relay (40) is arranged to be connected to one or more internal telephone lines in parallel to the internal communication line.
20. A switching apparatus according to any preceding claim, wherein the data processing means (30) is arranged to be able to be connected with a diagnostic monitor for testing purposes.
21. A switching apparatus according to any preceding claim, wherein the data processing means (30) is arranged to receive a control audio signal from the or each remote telephony.
22. A switching apparatus according to any preceding claim, wherein the data processing means (30) comprises display switches (34) indicating the status of predetermined parameters of the switching apparatus.
23. A remote monitoring system comprising a monitor (17) and a telephone (15), both connected to a switching apparatus (13) at a remote site (11), the switching apparatus (13) being arranged to be connected with a communication line to a central base station (12) through a receiver modem (19), the switching apparatus (13) being arranged to communicate either a data signal received from the monitor (17) of an audio signal received fcrn the telephone (15), along the communication line to the receiver modem (19) for processing by a central computer (18) at the base station (12),
24. A remote monitoring system according to claim 23, wherein the base station central computer (18) is arranged to operate the switching apparatus (13) to transfer either the data signal or the audio signal to the receiver modem (19).
25. A switching apparatus constructed and arranged substantially as herein described as shown in the drawings.
26. A remote monitoring system constructed and arranged substantially as herein described as shown in the drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AUPJ114888 | 1988-10-25 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8923976D0 GB8923976D0 (en) | 1989-12-13 |
| GB2225514A true GB2225514A (en) | 1990-05-30 |
Family
ID=3773468
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8923976A Withdrawn GB2225514A (en) | 1988-10-25 | 1989-10-25 | A switching apparatus for data and audiocommunication |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2225514A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2242100A (en) * | 1990-03-14 | 1991-09-18 | Tunstall Security Limited | Alarm communication controller |
| US5345046A (en) * | 1991-07-23 | 1994-09-06 | Otis Elevator Company | Voice communication for elevator |
| EP1092668A1 (en) * | 1999-10-11 | 2001-04-18 | Mac Puar S.A. | Emergency telephone for elevators and programming procedure |
| WO2001065825A2 (en) * | 2000-03-01 | 2001-09-07 | Midi Constructions Metalliques Micome | Device for monitoring premises comprising an emergency telephone |
| FR2816606A1 (en) * | 2000-11-16 | 2002-05-17 | Otis Elevator Co | Lift supervisor system having controller and anomaly/breakdown supervision system detected breakdown information/persons trapped passed and operator successive list passed reestablishing lift function |
| WO2018065740A1 (en) * | 2016-10-06 | 2018-04-12 | Sodimas | Communication between a lift installation and a remote server |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0236878A2 (en) * | 1986-03-08 | 1987-09-16 | Telenorma Gmbh | Small private telephone exchange, especially a key telephone exchange |
-
1989
- 1989-10-25 GB GB8923976A patent/GB2225514A/en not_active Withdrawn
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0236878A2 (en) * | 1986-03-08 | 1987-09-16 | Telenorma Gmbh | Small private telephone exchange, especially a key telephone exchange |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2242100A (en) * | 1990-03-14 | 1991-09-18 | Tunstall Security Limited | Alarm communication controller |
| US5345046A (en) * | 1991-07-23 | 1994-09-06 | Otis Elevator Company | Voice communication for elevator |
| EP1092668A1 (en) * | 1999-10-11 | 2001-04-18 | Mac Puar S.A. | Emergency telephone for elevators and programming procedure |
| WO2001065825A2 (en) * | 2000-03-01 | 2001-09-07 | Midi Constructions Metalliques Micome | Device for monitoring premises comprising an emergency telephone |
| FR2805951A1 (en) * | 2000-03-01 | 2001-09-07 | Midi Const Metalliques Micome | Monitoring device for premises, e.g. lifts, using emergency telephone connected to public telephone network |
| WO2001065825A3 (en) * | 2000-03-01 | 2002-03-28 | Midi Const Metalliques Micome | Device for monitoring premises comprising an emergency telephone |
| FR2816606A1 (en) * | 2000-11-16 | 2002-05-17 | Otis Elevator Co | Lift supervisor system having controller and anomaly/breakdown supervision system detected breakdown information/persons trapped passed and operator successive list passed reestablishing lift function |
| WO2018065740A1 (en) * | 2016-10-06 | 2018-04-12 | Sodimas | Communication between a lift installation and a remote server |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8923976D0 (en) | 1989-12-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |