EP0258915A1

EP0258915A1 - Device for remote control of conditions, processes and breakdowns on lifts, elevators, escalators and the like by means of transmission on local and trunk telephone lines

Info

Publication number: EP0258915A1
Application number: EP87201405A
Authority: EP
Inventors: Paolo Celentano
Original assignee: LIFT SECURITY SYSTEM Srl
Current assignee: LIFT SECURITY SYSTEM Srl
Priority date: 1986-08-04
Filing date: 1987-07-22
Publication date: 1988-03-09

Abstract

Device for remote control of conditions, processes and breakdowns on lifts, elevators, escalators and the like by means of transmissions on local and trunk telephone lines, in which a peripheral unit (11) is comprised in cooperation with the usage means to be controlled or with part thereof and can be connected to a central operating unit (10) positioned at a distance by means of a telephone line, the peripheral unit (11) including at least:

a telephonic interface (13),
an acquisition and transmission interface (14),
a microprocessor with resident storage (19),
a unit to organise readings (21),
a unit (23) to read the situation existing in detectors (24), a self-diagnosis unit (20),
a unit (22) to identify its own code, and
a unit (22) to identify the telephone number for connection to the central operating unit (10).

Description

This invention concerns a device for remote control of conditions, processes and breakdowns existing on lifts, elevators, escalators and the like by means of transmissions on local and trunk telephone lines.
To be more exact, this invention concerns a device able to transmit from a distance a plurality of signals concerning the situation existing in various parts of transport means such as lifts, escalators, etc.
Transmission of the signals takes place by normal telephone lines with signals on the network, the band of frequency of the signals being comprised in the audio band of local telephone lines.
Some lift equipment is controlled at present by a computer positioned at a distance. Such computer is connected to the specific usage means by a telephone line intended for the purpose and served by a modulator/detector working at frequencies above the audio band. The employment of a modulator/detector working at frequencies above the audio band is made necessary by a plurality of factors such as disturbances on the line, transmission anomalies,the great number of messages to be transmitted, etc.
The employment of modulators/detectors entails costs of instalment, equipment and maintenance and makes such a system unsuitable for the control of small units.
Various disclosures envisaging this method of a solution of the problem are known in the art.
US 3,973,648 discloses a system for the remote control of conditions in lifts by the use of the telephone network. Signals for such remote control are sent by means of a modem.
US 3,801,743 discloses a device which transmits automatically a signal corresponding to the telephone number required.
US 4,056,684 discloses a remote control system but does not indicate clearly the methods employed in the transmission of signals nor the nature and conformation of such signals.
US 4,493,948 discloses a system which transmits by means of a modem and which is connected to a serial input/output of a computer. This device can work only on particular telephone lines such as those of the USA since the coupling is capacitive, namely with condensers, and not inductive, namely with a transformer.
US 4,491,198 discloses a device analogous to that of US 4,493,948.
To overcome the drawbacks of the known art and to be able to control and remote-control transport equipment such as lifts, elevators, escalators and the like the present applicant has designed, tested and embodied the present invention.
The structure of a possible device suitable to embody the invention consists of a central acquisition unit or central operating unit and various peripheral units connected to the central operating unit by normal telephone lines.
The peripheral units acquire data regarding the operating conditions existing in the transport equipment connected to those units and send such data to the central operating unit, which monitors the existing situation, processes it, displays it and prints and stores it.
The device can also perform diagnostic tests of the controlled system by simulating given sequences of operation and testing the accuracy of performance within given limits.
Any anomalous condition detected at any time causes the start-up of the procedure for notification of a malfunction with the transmission to the central operating unit of suitable information indicating the source and type of malfunction or anomaly.
The conversation by telephone line between the central operating unit and the peripheral unit in question is ended with a reply from the central unit to the effect that the message has been received.
The configuration of the system provides for the employment of a central computer envisaged as a control and reference receiver unit for the peripheral units, the computer comprising a file in which the notification calls insert all the events to be processed.
The range of tests which each peripheral unit can carry out can be varied as required.
According to the invention the transmission of data takes place by despatch of at least one train of signals of a high- low type, each train being organized with a plurality of bytes.
Each train of signals contains all the information needed to define the situation existing in the equipment controlled by the peripheral unit.
According to a minimum formulation the train of signals is organized as follows:

- a first group of bytes serves to identify the peripheral unit which is being controlled or which has called;
- a second group of bytes serves to identify, position by position, the state of the equipment being controlled; the invention arranges to characterize each bit with a specific valence in relation to a specific function being controlled;
- a third group comprises the summation of the preceding groups forming the train; this summation takes place by giving a weight to each byte transmitted, adding the various weights together and comparing such sum broken down into the factors available in the summation byte.

Each byte can provide eight or more bits, which are advantageously multiples of eight so as to assist the packing of the information.
As said above, the central operating unit receives a given number "N" of bytes containing the required information, stores provisionally the last byte containing the summation data and proceeds to verify its equality with the preceding "N minus 1" bytes.
If such equality is found, the central operating unit stores definitively the data contained in the train of bytes received.
So as to transmit in the audio band over a normal telephone line and to be at the same time substantially immune from changes due to line disturbances during transmission, the invention provides for the employment of a low speed of transmission of the individual signals.
According to the invention the time allowed for each individual signal forming the train of bytes is between 10 and 500 microseconds but is advantageously about 200 microseconds.
To determine the "zero" and "one" signals, the invention employs two different frequencies, which have a difference of between 50 Hz and 2000 Hz, a difference between about 800 and 1000 Hz being advantageous.
The "zero" value or low signal value, the lowest value of frequency being taken as the "zero" value here as an example, is determined according to the invention by a frequency between 600 and 2500 Hz, a frequency value of about 1000 _Hz being advantageous.
According to the invention a third frequency is provided with the function of reciprocal confirmation between the peripheral unit and the central operating unit. This frequency lies within the audio band and may be located at any position within that band provided that it is differentiated from the other two frequencies and provided that the differentiation is at least 50 Hz and advantageously 800-1000 Hz.
The invention is therefore embodied with a device for remote control of conditions, processes and breakdowns on lifts, elevators, escalators and the like by means of transmissions on local and trunk telephone lines, in which a peripheral unit is comprised in cooperation with the usage means to be controlled or with part thereof and can be connected to a central operating unit positioned at a distance by means of a telephone line, the device being characterized according to the content of Claim 1 and the dependent claims.
The attached figures, which are given as a non-restrictive example, show the following:-

Fig.l shows a block diagram of an embodiment according to the invention;
Fig.2 shows a functional block diagram of a peripheral unit and a central operating unit;
Fig.3 shows a preferred train of bytes.

In the figures the same parts or parts performing the same functions bear the same reference numbers.
Figs.l and 2 show two block diagrams of a plant as an example. Fig.l shows the plant in a summarized form, whereas Fig.2 gives a more detailed diagram of the plant.
In the plant a central operating unit 10 is connected to a peripheral unit 11 by a normal telephone line 12. Each peripheral unit 11 controls an equipment or part thereof.
In one diagram of a lay-out the central operating unit 10 comprises a telephonic interface 13, an acquisition and transmission interface 14, a normal computer 15, a monitor 16, a printer 17 and a storage unit 18.
The peripheral unit 11 comprises diagrammatically a telephonic interface 13, an acquisition and transmission interface 14, a microprocessor 19 with a relative resident storage, a programmer unit 20 with self-diagnosis capability, a unit 21 to organise readings, a unit 22 to identify its own code and the telephone number for connection to the central operating unit 10, a unit 23 to read situations existing in detectors 24 located at the points to be controlled, a unit 25 to monitor measurements and an isolation unit 26.
The telephonic interface 13 connects the computer 15 to a telephone line 12. An equal telephonic interface 13 is also comprised in the peripheral unit 11 and serves to isolate the telephone line electrically from the remaining apparatus.
Moreover, the interface 13 amplifies and optimises the incoming and outgoing signals.
Furthermore, the telephonic interface 13 forms the telephone number required,
The acquisition and transmission interface 14 supplies to the telephonic interface 13 the commands for formation of the telephone number and receives the incoming information from the telephonic interface 13.
The acquisition and transmission interface 14 receives and sends information to the computer 15 or microprocessor 19 respectively.
The computer 15 handles the acquired information, encodes information which can be converted into trains of bytes, stores information in the storage unit 18, prints it on the printer 17 and displays it on the monitor 16.
In this example the function of the peripheral units 11 is to notify the central operating unit 10 about a breakdown or anomaly, the type and source of a breakdown and the presence or otherwise of the service technician and also to supply all other programmed information to the central operating unit 10.
The peripheral unit 11 can control various detector devices 24, handle telephone messages, form a telephone number, send its own code, indicate existing anomalies, wait for verification and repeat the call and transmission cycle in the event of faulty or non-existent reception or an engaged line.
Besides the telephonic interface 13 and acquisition and transmission interface 14, the peripheral unit comprises, as we said earlier, a plurality of components, among which the microprocessor 19 with relative resident storage organises the storage, the digital acquisitions and their processing and conditioned output functions.
The self-diagnosis programmer unit 20 has the task of determining a self-test of the peripheral unit 11 so as to ascertain the proper functioning thereof.
The unit 21 which organises the readings organises the acquisitions from 22 and 23 and converts them into digital information for the microprocessor 19 with resident storage.
Fig.3 shows a preferred train of bytes functioning in harmony with the device of the invention. This train provides for bytes of eight bits.
In the case in question arrangements have been made for up to 999 controlled peripheral units.
The outgoing signal is always high or low; in the example shown it is high and the START signal (corresponding to a low signal in this case) is the first bit preceding each byte.
A double STOP bit is provided at the end of each byte so as to enable the computer to acquire the byte just received. This STOP signal is a high signal in this example.
Identification of the peripheral units and therefore of the equipment or part of the equipment takes place by using the binary code to indicate the hundreds (A), tens (B) and units (C) respectively.
The successive bytes are organised as follows; the fourth byte (D) and fifth byte (E) serve to provide information about the functions controlled.
The sixth byte (F) acts as a reserve and, for instance, serves to identify the presence er absence of the maintenance fitter.
The seventh byte (G) serves to determine the summation of the individual weights of each preceding byte.
Each bit in bytes D, E and F provides its own specific information regarding the specific correlated function.
Thus, according to the symbols employed a high signal may be intended to say that the function represented and therefore controlled is in working order, whereas a low signal means that the function controlled is out of order.
As an example, the eight bits in byte D may indicate:

- alarm with person shut in,
- vibration of the lift car,
- motive power of electrical supply line,
- power of lighting,
- voltage in the operations (servocontrols),
- safety checks,
- excessive absorption by the motor,
- free.

As another example, the eight bits in byte E may indicate:

- closure of outside doors working,
- door lock closures working,
- photoelectric cell or auxiliary safety enclosures working,
- peripheral anti-tampering unit,
- fire-warning sensors,
- lift car light working,
- detection of breakdowns by microprocessor controls,
- free.

Each byte forming the train can be interpreted as a binary value in which each position takes up a value in the scale 1, 2, 4, 8, 16, 32, 64 and 128 in the case of eight bits.
By performing a summation of the weights of each single bit having,for instance, a high signal (or viceversa a low signal) in each single byte of the six bytes preceding the last one, the summation value expressed in binary code is obtained.
This summation value is filtered, and only the last eight figures read in the last byte (G) are considered.
If this summation corresponds with the summation calculated by the computer 10, then the information received is confirmed as valid.
Therefore, each train of bytes contains information characterized in three different ways.
A first set of information, which is necessary in the case of the inclusion of a plurality of peripheral units and serves to identify alphanumeric characters that identify the peripheral unit in question, is contained in the bytes, so that each byte represents one single alphanumeric character.
A second set of information, which serves to identify the existing conditions of the various functions controlled by the specific peripheral unit, is provided by one or more bytes,in which each component bit is devoted to one specific function alone.
A third set of information, which serves to control the correctness and integrity of the bytes containing the relevant information,is contained in a byte in which the byte indicates the figure obtained by the summation of the individual weights of the single bytes containing the relevant information.

Claims

1 - Device for remote control of conditions, processes and breakdowns on lifts, elevators, escalators and the like by means of transmissions on local and trunk telephone lines, in which a peripheral unit (11) is comprised in cooperation with the usage means to be controlled or with part thereof and can be connected to a central operating unit (10) positioned at a distance by means of a telephone line,the device being characterized in that the peripheral unit (11) includes at least:

- a telephonic interface (13),

- an acquisition and transmission interface (14),

- a microprocessor with resident storage (19),

- a unit to organise readings (21),

- a unit (23) to read the situation existing in detectors (24),

- a self-diagnosis unit (20),

- a unit (22) to identify its own code, and

- a unit (22) to identify the telephone number for connection to the central operating unit (10).

2 - Device as claimed in Claim l,in which the central operating unit (10) includes:

- a telephonic interface (13),

- an acquisition and transmission interface (14), and

- a computer (15).

3 - Device as claimed in any claim hereinbefore, in which the telephonic interfaces (13) converse in the audio band with signals (BITS) cooperating with two characteristic frequency bands, the individual signals (BITS) being organised in sequences (BYTES) which can be programmed.

4 - Device as claimed in any claim hereinbefore, in which the characteristic frequencies are used for the telephonic interfaces (13) to give the signal (BIT) a high or low value, there being between the two frequencies a difference of between 50 and 2000 Hz, a difference of about 800-1000 Hz being advantageous.

5 - Device as claimed in any claim hereinbefore, in which the characteristic frequency employed for the low value is between 600 and 2500 Hz, a value of about 1000 Hz being advantageous. 6 - Device as claimed in any claim hereinbefore, in which each single bit (BIT) lasts from 10 to 500 microseconds, a duration of about 200 microseconds being advantageous.

7 - Device as claimed in any claim hereinbefore, in which a reciprocal confirmation signal is also provided in the audio band and is differentiated from the other two characteristic frequencies, the differentiation being by at least 50 Hz and advantageously 800-1000 Hz.

8 - Device as claimed in any claim hereinbefore, in which the information is organised in a defined train of "N" bytes, one byte (G) being employed for control and verification purposes.

9 - Device as claimed in any claim hereinbefore, in which, if there are several peripheral units (11), "n" bytes (A-B-C) of alphanumeric recognition of the specific peripheral unit (11) concerned are included in the train of "N" bytes.

10 - Device as claimed in any claim hereinbefore, in which the train of "N" bytes includes at least one byte (D-E-F) containing specific bits each of which indicates the physical state of one individual, specific, controlled function.

11 - Device as claimed in any claim hereinbefore, in which the control and verification byte (G) indicates in a binary number the value of the summation of the weights of the other bytes (A-B-C-D-E-F).

12 - Device as claimed in any claim hereinbefore, in which the bytes (A-B-C) of alphanumeric recognition of the specific peripheral unit (11) indicate one character with each byte.