BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to a communication technique for an elevator system.
Description of the Background Art
[0002] In a conventional elevator system, since various elevator equipments, such as switches
and sensors have been individually connected to a control panel, a large number of
wires have been required.
[0003] Therefore, Japanese Patent Application Publication (translation of PCT Application)
No.
2002-538061 has disclosed a technique in which among various elevator equipments, those relating
to safety control are connected to a bus node, and the bus node is connected to a
safety controller through a safety bus, thereby reducing the number of wires.
[0004] Moreover, Japanese Patent Application Laid-Open No.
2004-48474 has disclosed a technique in which various signals for the elevator equipments are
unwired, thereby reducing the number of wires.
[0005] However, in the elevator system described in Japanese Patent Application Publication
(translation of PCT Application) No.
2002-538061, there is a problem that the reduction of the number of wires is insufficient, since
only the signals relating to safety control are connected through the bus node (serialized).
Moreover, even if the other signals were also connected through the bus node, a problem
would be still raised in that elevator functions are not maintained at the time of
occurrence of a communication error.
[0006] Moreover, in the elevator system described in Japanese Patent Application Laid-Open
No.
2004-48474, in the case of occurrence of a communication error or in the case when a radio communication
becomes incapable because of a blackout or the like, elevator functions are not maintained
since all the communications become incapable.
SUMMARY OF THE INVENTION
[0007] The object of the present invention is to provide an elevator system that reduces
wires and suppresses a loss of functions even in an abnormal state.
(Constitution 1)
[0008] The elevator system of the present invention includes a first communication controller,
a second communication controller and control means. The first communication controller
is installed in an elevator cage, an elevating path or a platform, and connected to
an elevator equipment inside the elevator cage, an elevator equipment inside the elevating
path, or an elevator equipment of the platform. The second communication controller
is connected to the first communication controller through a serial communication
network and an individual communication line so as to perform communication. The control
means is connected to the second communication controller so as to control operations
of the elevator cage. The individual communication line communicates a signal individually
in a manner separated from a signal communicated through the serial communication
network.
(Effects 1)
[0009] With a structure in which a serial communication network is used for connecting between
the first and second communication controllers, it becomes possible to reduce the
number of communication lines in comparison with a structure in which the respective
elevator equipments installed in the cage are respectively connected to the control
panel. Moreover, even in the case of a failure in communication by the serial communication
network, it is possible to suppress a loss of functions in an abnormal state by carrying
out communications using individual communication lines.
[0010] These and other objects, features, aspects and advantages of the present invention
will become more apparent from the following detailed description of the present invention
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
FIG. 1 is a block diagram that shows a configuration of an elevator system in accordance
with a first preferred embodiment;
FIG. 2 is a block diagram that shows a configuration of a communication controller
of the first preferred embodiment;
FIG. 3 is a block diagram that shows a hardware configuration of the communication
controller of the first preferred embodiment;
FIG. 4 is a view that shows a frame configuration of a transmission signal for use
between the communication controllers;
FIG. 5 is a flow chart that shows a transmission process of the communication controller;
FIG. 6 is a flow chart that shows a receiving process of the communication controller;
and
FIG. 7 is a block diagram that shows a configuration of an elevator system in accordance
with a second preferred embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(First Preferred Embodiment)
<A. First Preferred Embodiment>
<A-1. Configuration>
[0012] FIG. 1 is a view that shows a configuration of an elevator system in a first preferred
embodiment of the present invention. The elevator system includes a cage 5 and a control
panel 4 that controls operations of the cage 5. The control panel 4 includes a communication
controller 1a, and the cage 5 has a communication controller 1b connected with the
communication controller 1a through a parallel communication-use network 2 and a serial
communication-use communication line 3 installed therein. Here, although the preferred
embodiment for two communication controllers is shown, the number of the communication
controllers is not necessarily limited thereto, and three or more of them may be used.
[0013] In the cage 5, various elevator equipments are installed, including an interphone
13b through which voice input and output are carried out, a safety switch-sensor 15,
a normal control switch-sensor 16, a monitoring camera 17, a monitor 18, a card reader
19 for a serial communication device for use in providing security functions, a door
controller 20, a door motor 21, a safety shoe 22, etc.
[0014] The safety switch-sensor 15 is a switch-sensor that detects a state of the cage 5
relating to safety control, and outputs the result of detection as a safety signal.
For example, a floor touch sensor, a door switch, or the like corresponds to this
sensor. The normal control switch-sensor 16 is a switch-sensor that detects a state
of the cage 5 not relating to the safety control, and outputs the result of detection
as a normal control signal. For example, a position switch for detecting a positional
plate (not shown) placed inside an elevating path, or the like corresponds to this
sensor.
[0015] The door controller 20 controls the opening/closing of a door (not shown) of the
cage 5 and the safety shoe 22 by driving the door motor 21.
[0016] Moreover, various elevator equipments, such as a managing board 10, a picture recording
device 11, an image distribution device 12, an interphone 13a and the like, are connected
to the control cable through the control panel 4, or directly connected thereto.
[0017] The managing board 10 carries out security managements (for example, a registration
permission, or the like, to a destination floor) in cooperation with the card reader
19. The picture recording device 11 records images picked up by the monitoring camera
17. The image distribution device 12 outputs an image to be displayed on the monitor
18. The interphone 13a carries out voice input and output so as to provide a communication
function with the interphone 13b installed in the cage 5.
[0018] Moreover, in the control panel 4 (or a machine house, or a superintendent room, or
the like), a battery 14 serving as an auxiliary power supply to be used at the time
of a power loss of a main power supply due to a blackout or the like is installed,
and the control device 7 and the safety control device 6 are further installed therein.
These constituent components installed in the control panel 4 or the like are connected
to the communication controller 1a in a completely independent manner. Additionally,
among the various elevator equipments inside the control panel 4, as shown in FIG.
1, the respective constituent components except for the control device may be installed
in the machine house or the superintendent room outside the control panel 4. In the
case where these are installed in the machine house or the superintendent room, they
are connected with the communication controller 1a through the control panel 4.
[0019] The safety control device 6 and the control device 7 are connected to a hoist gear
8 and a brake 9, and by driving them, a movement of the cage 5 is controlled. Based
upon information of various elevator equipments received from the communication controller
1a, the control device 7 controls a driving process of the cage 5 during normal operation.
[0020] On the other hand, based upon information of various elevator equipments received
from the communication controller 1a, the safety control device 6 carries out controls
relating to safety of the cage 5 (such as monitoring of an over speed or prevention
of travelling with the door being open) so that in the case when any abnormal state
is detected in the cage 5, at least one of the power supplies of the hoist gear 8
and the brake 9 is shut off so as to bring the cage 5 to a stop at the nearest floor
or to an emergency stop.
[0021] FIG. 2 is a block diagram showing a configuration of the communication controller
1a. The communication controller 1b also has the same configuration as this. The communication
controller 1a includes a network communication I/F 30, a safety signal I/F 36, a normal
control signal I/F 37, a voice signal I/F 38, an image signal I/F 39 and a serial
signal I/F 40 as interfaces for use in connecting with the various elevator equipments.
Each of the interfaces digital/analog converts a signal from the communication controller
1a to each of the various elevator equipments, and analog/digital converts a signal
from each of the various elevator equipments to the communication controller 1a. Moreover,
it also carries out an encoding process, a decoding process and a protocol conversion
process.
[0022] Moreover, the communication controller 1a includes a transmission unit 31, a receiving
unit 32, a scheduling and systemizing unit 33, a distribution unit 34 and a safety
communication unit 35. The safety communication unit 35 adds error-detection information
to a safety signal received from the safety signal I/F36 in a transmission stage,
and carries out an error detection based upon the error-detection information in a
receiving stage. The scheduling and systemizing unit 33 determines transmission schedules
of respective signals. The transmission unit 31 transmits signals from the network
communication I/F 30 to the other communication controller in accordance with the
transmission schedules determined by the scheduling and systemizing unit 33. The receiving
unit 32 receives signals from the other communication controller through the network
communication I/F 30. The distribution unit 34 distributes the signals received by
the receiving unit 32 to any of the interfaces except for the safety signal I/F 36,
or to the safety communication unit 35.
[0023] FIG. 3 is a view showing a hardware configuration of the communication controller
1a. The communication controller 1b has the same configuration as this. The safety
communication unit 35 includes a CPU (Central Processing Unit) 51, a ROM (Read Only
Memory) 52, a RAM (Random Access Memory) 53 and a WDT (Watch Dog Timer) 54. Each of
various interfaces includes a DAC (Digital to Analog Converter) 55, an ADC (Analog
to Digital Converter) 56, an encoder 57, a decoder 58 and a protocol conversion chip
59.
[0024] The network communication I/F 30 is composed of PHY (PHYsical layer) chips 61. The
transmission unit 31, the receiving unit 32, the distribution unit 34, the scheduling
and systemizing unit 33 are composed of FPGA (Field Programmable Gate Array) 60; however,
CPU and ASIC (Application Specific Integrated Circuit) or CPLD (Complex Programmable
Logic Device) may also be used. The DAC 55, ADC 56, encoder 57, decoder 58 and protocol
conversion chip 59 may be contained in an FPGA 60. The respective parts are connected
with one another through buses 62 and connection lines so that various data and signals
are exchanged with one another.
<A-2. Operations>
[0025] FIG. 4 shows a frame configuration of messages communicated between the communication
controllers 1a and 1b. Each message includes an address 83, a source 84, a length/type
85, a data portion 86 and a frame CRC (Cyclic Redundancy Check) codes 87. In the data
portion 86, a data type 82 and a data main body including serial communication data
81, voice signals 80, image signals 79 and normal control signals 78, are stored.
To a message for use in transmitting a safety signal, a safety message 71 is added
in addition to the above. The safety message 71 includes an address 72, a source 73,
a type 74, a sequential number 75, a safety signal 76 and a safety CRC 77. Additionally,
the data type 82 may be substituted by the length/type 85.
[0026] FIG. 5 is a view that shows a transmitting process from the communication controller
1b to the communication controller 1a. The communication controller 1b receives signals
from various elevator equipments of the cage 5, and transmits the same to the communication
controller 1a.
[0027] The scheduling and systemizing unit 33 sets the degree of preference, reliability
and response of each of the various signals, and based upon these, preliminarily determines
transmission schedules and the number of continuous transmissions of the various signals
(step S1). For example, in the safety message 71, the highest degree of preference
and the number of continuous transmissions are set to comparatively high levels, and
in the normal control signal 78, the number of continuous transmissions is set to
a comparatively low level. Moreover, in the voice signal 80 and image signal 79 having
a low precedence degree, continuous transmissions are not carried out, and in the
case when the bandwidth of a transmission path is insufficient, such a setting as
to carry out a thinning process thereon is prepared.
[0028] The respective elevator equipments installed in the cage 5 are connected to the safety
signal I/F 36, the normal control signal I/F 37, the voice signal I/F 38, the image
signal I/F 39 and the serial signal I/F 40 of the communication controller 1b, and
signals from the respective elevator equipments are inputted to these interfaces.
Thus, the communication controller 1b is allowed to determine the type of an input
signal (step S2). The types of the input signal are classified into a safety signal,
a normal control signal, a voice signal, an image signal, and a serial communication.
The safety signal, which represents a signal showing the state of the safety switch-sensor
15, is inputted to the safety signal I/F 36. The normal control signal, which represents
a signal showing the state of the normal control switch-sensor 16, is inputted to
the normal control signal I/F 37. Moreover, the voice signal, which is a signal from
the interphone 13b, is inputted to the voice signal I/F 38. The image signal, which
is a signal from the monitoring camera 17, is inputted to the image signal I/F 39.
Moreover, the serial signal, which is a signal from the card reader 19, is inputted
to the serial signal I/F 40.
[0029] Upon incorporating an input signal through each of the interfaces, the safety signal
and the normal control signal are subjected to an A/D conversion (steps S3 and S5),
and the voice signal and the image signal are subjected to an encoding process (steps
S6 and S7). Moreover, the serial communication signal is subjected to a protocol conversion
(step S8).
[0030] To the safety signal incorporated through the safety signal I/F 36 is then added
error detection information in the safety communication unit 35 so that a safety message
71 is generated (step S4). For example, a safety CRC 77 and a sequence number 75 are
added thereto as the error detection information so as to generate the safety message
71 (see lower portion of FIG. 3).
[0031] These respective input signals 78 to 81 and the safety message 71 are sent to the
scheduling and systemizing unit 33, and stored in the data unit 86 and formed into
a frame in accordance with the transmission schedule determined in the step S1 (step
S9). Moreover, the frame is duplicated by the number of continuous transmissions determined
in the step S1 and sent to the transmission unit 31 (step S10), and then transmitted
to the network 2 through the network communication I/F 30 (step S11).
[0032] At this time, in the case when the same schedules and numbers of continuous transmissions
are commonly used among a plurality of signals, those may be combined into one message
and then sent. Moreover, even in the case when only the same schedules are commonly
used, by matching to the highest number of continuous transmissions, those may be
combined into one message and then sent.
[0033] The receiving unit 32 monitors communication errors, and counts the number of occurrences
of communication errors per unit time as a communication error occurrence frequency,
and determines the quality of a communication path based upon the communication error
occurrence frequency. It is supposed that the relationship between the communication
quality and the communication error occurrence frequency is preliminarily determined
and held in the communication controller 1b. When the communication quality is varied,
the receiving unit 32 notifies the scheduling and systemizing unit 33 of the information
of communication quality (step S12).
[0034] Upon receipt of the notification, the scheduling and systemizing unit 33 re-determines
the schedule in accordance with the communication quality (step S13). For example,
in the case when the communication quality is lowered, the number of transmissions
(continuous transmissions) of signals having a higher precedence degree is increased.
Moreover, the number of transmissions (continuous transmissions) of signals having
a lower precedence degree is reduced, or a transmission is carried out, with those
signals in which no reliability is required being thinned.
[0035] In contrast, in the case when the communication quality is improved, the number of
transmissions (continuous transmissions) of signals having a higher precedence is
reduced, or the number of transmissions (continuous transmissions) of signals having
a lower precedence is increased, or those signals that have been thinned are refrained
from being thinned, or the number of thinning signals is reduced.
[0036] Next, receiving processes of the communication controller 1a will be described along
a flow chart of FIG. 6. The receiving unit 32 of the communication controller 1a receives
a message from the network 2 through the network communication I/F 30 (step S21).
The distribution unit 34 conducts an inspection for the frame CRC 87, and determines
whether or not any normal frames are present among a plurality of identical messages
continuously transmitted (step S22).
[0037] If none of normal frames are present in step S22, then a determination is made as
to whether or not a specified period of time has been reached (step S34), and if it
has been reached, then the cage 5 is brought to an emergency stop (step S29). In this
case, the communication controller 1a notifies the safety control device 6 of the
fact that the cage 5 needs to be brought to an emergency stop, and the safety control
device 6 shuts off the power supply for the hoist gear 8 and the brake 9 so that the
cage 5 is stopped at once. Alternatively, the communication controller 1a itself may
shuts off the power supply for the hoist gear 8 and the brake 9. After the emergency
stop, the stopped state of the cage 5 is maintained until a restoration work is carried
out by the maintenance worker. In the following description, the process of the emergency
stop is carried out in the same manner.
[0038] If there are any normal frames in step S22, the distribution unit 34 takes out one
of those frames, and distributes data for each of signal types (step S23). Next, in
step S24, the type of an input signal is determined. In the case when no safety signal
has been received, the notification is given to the safety communication unit 35,
and the safety communication unit 35 determines whether or not a specified period
of time has been reached (step S34), and if it has been reached, then the cage 5 is
brought to an emergency stop (step S29). Additionally, if the specified period of
time has not been reached, a process may be carried out in which the cage 5 is made
to stop at the nearest floor (step S28). In this case, the safety communication unit
35 notifies the control device 7 so as to stop the cage 5 at the nearest floor so
that the control device 7 stops the cage 5 at the nearest floor. Thereafter, reactivation
is carried out to attempt restoration of operations of the network 2 and the cage
5. In the case when, however, no restoration is made even after carrying out a predetermined
number of times or more of reactivations, the stopped state of the cage 5 is maintained
so as to wait for its restoration by the maintenance worker. In the following description,
the process for stopping at the nearest floor is carried out in the same manner. In
the case when a safety signal has been received, the safety message 71 is transferred
to the safety communication unit 35, and in the safety communication unit 35, by using
error detection information in the safety message 71, an error detection (inspection
for the safety CRC 77 and the sequence number 75) is carried out (step S25). In the
case when no error is detected in step S25, the safety signal is outputted to the
safety control device 6 and the control device 7 through the safety signal I/F 36
(step S26), and the sequence returns to step S21 to receive the next message.
[0039] If any error is detected in step S25, a determination is made as to whether or not
the number of error detections has reached a predetermined number of times (step S27),
and if the predetermined number has not been reached, the cage 5 is made to stop at
the nearest floor (step S28).
[0040] Moreover, when the number of error detections has reached a specified number of times
in step S27, the cage 5 is brought to an emergency stop (step S29).
[0041] In the case of a signal other than the safety signal, the corresponding signal is
outputted to various elevator equipments through the interfaces 37 to 40 for various
signals. For example, a normal control signal is D/A converted in the normal control
signal I/F 37 (step S30), and then outputted to the control device 7. Moreover, a
voice signal is decoded in the voice signal I/F 38 (step S31), and then outputted
to the interphone 13a or the like. Furthermore, an image signal is decoded in the
image signal I/F 39 (step S32), and then outputted to the picture recording device
11 or the like. A serial signal is protocol-converted in the serial signal I/F 40
(step S33), and then outputted to various elevator equipments, such as the managing
board 10.
[0042] The safety communication unit 35 has also self-diagnosis functions, such as an inspection
for CPU 51 by a self-testing program, a time monitoring process during execution by
the WDT 54, a read/write inspection of the RAM 53, a CRC inspection of the ROM 52,
comparisons of input/output signals of a double system and a monitoring process of
an input/output signal by back reading of an output signal, and ensures high reliability
in dealing with information relating to safety control. Additionally, the safety communication
unit 35 may be provided with redundancy.
[0043] Upon detection of a failure of its own by the self-diagnosis functions, the safety
communication unit 35 notifies the safety control device 6 or the like of the failure.
In the case when the failure of the safety communication unit 35 is a temporary minor
failure caused by a garbled bit or the like, the safety control device 6 brings the
cage 5 to a stop at the nearest floor, while in the case when the failure is a serious
failure such as fixation of an output signal or the like, it brings the cage 5 to
an emergency stop.
[0044] The present specification has given explanations by exemplifying the structure in
which information of the elevator equipments installed in the cage 5 is transmitted
from the communication controller 1b to the communication controller 1a and then outputted
to elevator equipments connected to the control panel 4. However, in the case when
communication is carried out in a reversed direction, such as a transmission of a
control signal from the control device 7 to the door controller 20 or a transmission
of an image signal from the image distribution device 12 to the monitor 18, the processes
in the both of the communication controllers 1a and 1b can be simply reversed. In
this case, an occurrence of a communication error is informed to the communication
controller 1a on the control panel 4 side from the communication controller 1b by
using an individual communication line 3, and based upon the contents thereof, the
cage 5 may be continuously operated, or brought to a stop at the nearest floor, or
brought to an emergency stop by the safety control device 6 and the control device
7 (or an instruction may be given to the safety control device 6 and the control device
7 so as to continue the operation, or make a stop at the nearest floor, or make an
emergency stop by using the individual communication line 3). Alternatively, in the
case when the safety control device and the control device are connected to the communication
controller 1b and installed in the cage 5 as control means on the cage side for controlling
the operations of the cage 5, based upon the contents of a communication error in
the communication controller 1b and the kinds of communication information, the cage
5 can be brought to a stop at the nearest floor, or brought to an emergency stop,
by the safety control device and the control device of the cage 5.
[0045] Moreover, communications between the communication controllers 1 were carried out
through the network 2. However, in the case when the communication of the network
2 is impossible because of a failure or the like of the communication circuit, it
is possible to carry out communication of a minimum required signal for a normal operation
of the elevator, such as a part of the safety signal or the like, by using a one-to-one
communication by the use of the communication line 3. Of course, in the case when
the communication carried out by the network 2 is normal, the one-to-one communication
by the communication line 3 may be used in combination.
[0046] Conventionally, with respect to the communication lines that connect various devices
with one another in an elevator system, a total number of 70 lines were required.
Those lines are classified into about 20 lines for the safety switch-sensor 15, about
20 lines for the normal control switch-sensor 16, about 5 lines each for the card
reader 19 for use in providing security functions, for the managing board 10, for
the interphones 13a and 13b, for the monitoring camera 17 and for the monitor 18,
and about 10 lines for the door controller 20.
[0047] In accordance with the elevator system of the present preferred embodiment, the number
of communication lines can be reduced to a total of 24 lines, that is, 4 lines required
for the network 2 (the twist pair entire double communication), and about 20 communication
lines that are minimum required for the operations of an elevator. Additionally, the
number is not limited thereto, depending on the structures of the elevator.
[0048] Moreover, in the elevator system of the present preferred embodiment, the battery
14 serving as an auxiliary power supply is installed in the control panel 4 (or in
the machine house, the superintendent room, or the like); therefore, even in the case
of a power loss of the main power supply at a blackout or the like, the communication
can be continued by making a switch to the auxiliary power supply. At this time, only
the communication that is minimum required for maintaining functions of the elevator
at the time of the blackout is continuously maintained, such as communications for
signal or the like required for rescuing passengers trapped therein, that is, the
signal or the like from, for example, the interphone 13 and the emergency notifying
device, or the like. With respect to functions relating to communications except for
this, power supplies are shut off, or brought to a power-saving mode. In the case
when the main power supply is restored, a switching is made to the main power supply,
and all the communications are restored. Additionally, the battery 14 may be installed
in each of the communication controllers 1a and 1b, or a common battery 14 may be
utilized, with a power supply line being connected between the communication controllers
1a and 1b.
<A-3. Effects>
[0049] The elevator system of the present preferred embodiment includes a first communication
controller (communication controller 1b) that is installed in an elevator cage (cage
5) or at an elevating path or a platform, and is connected to elevator equipments
in the cage 5, the elevating path or the platform; a second communication controller
(communication controller 1a) that is connected to the communication controller 1b
by a serial communication network (network 2) and an individual communication line
(communication line 3) and carries out communications; and control means (safety control
device 6, control device 7) that is connected to the communication controller 1a,
and controls operations of the cage 5 in which the communication line 3 communicates
a signal individually in a separate manner from a signal that is communicated through
the network 2. With the structure in which the network 2 is used for connecting between
the communication controllers 1a and 1b, it becomes possible to reduce the number
of communication lines in comparison with a structure in which the respective elevator
equipments installed in the cage or the like are respectively connected to the control
panel. Moreover, even in the case of a failure in communication by the network 2,
communications having a high degree of importance, such as, for example, a safety
signal or the like, can be positively carried out by carrying out communications using
individual communication lines. That is, in accordance with the elevator system of
the present preferred embodiment, the number of wires can be reduced, while preventing
the loss of functions upon occurrence of an abnormal state.
[0050] Moreover, based upon a transmission schedule in accordance with the degree of precedence
of a transmission signal in the network 2, the communication controllers 1a and 1b
transmit the transmission signal; therefore, communications for a signal having a
higher precedence degree, such as a signal relating to safety control, can be positively
carried out.
[0051] Moreover, since the communication controllers 1a and 1b monitor a communication error
in the network 2 and determine the schedule for the transmission signal based upon
a frequency of the communication error, it is possible to carry out a network communication
in accordance with the communication quality.
[0052] Furthermore, since the communication controllers 1a and 1b determine the schedule
for a transmission signal depending on a usable bandwidth of the communication path
in the network 2, network communications can be carried out in accordance with communication
quality.
[0053] In the case when information relating to safety control is communicated, the communication
controllers 1a and 1b add error detection information to the information relating
to safety control at the time of transmitting, and carry out an error detection by
using the error detection information at the time of receiving so that it is possible
to ensure reliability of communications required for safety control.
[0054] Upon occurrence of a communication error, the communication controller 1a determines
the contents of the communication error and the kinds of communication information,
and the safety control device 6 and the control device 7 allow the cage 5 to continue
operations, or bring the cage to a stop at the nearest floor, or to an emergency stop
based upon the determination of the communication controller 1a, so that even at the
time of a communication error, the safety of the elevator cage 5 can be ensured.
[0055] Moreover, the occurrence of a communication error is informed to the communication
controller 1a on the control panel 4 side from the communication controller 1b by
using the individual communication line 3, and based upon the contents thereof, the
cage 5 is continuously operated, or brought to a stop at the nearest floor, or brought
to an emergency stop by the safety control device 6 and the control device 7 (or an
instruction is given to the safety control device 6 and the control device 7 so as
to continue the operation, or make a stop at the nearest floor, or make an emergency
stop by using the individual communication line 3). Alternatively, in the case when
the safety control device and the control device are connected to the communication
controller 1b and installed in the cage 5 as control means on the cage side for controlling
the operations of the cage 5, upon occurrence of a communication error, the communication
controller 1b determines the contents of the communication error and the kinds of
communication information, and the safety control device and the control device allow
the cage 5 to continue the operations, or bring the cage 5 to a stop at the nearest
floor or to an emergency stop based upon the determination of the communication controller
1b. With the above-mentioned operations, it becomes possible to ensure the safety
of the elevator cage 5 even at the time of a communication error.
[0056] Moreover, since the elevator system in accordance with the present preferred embodiment
further includes an auxiliary power supply for supplying power at the time of power
loss of the main power supply, it is possible to ensure reliability that is minimum
required for the elevator communication by carrying out communications having a high
precedence degree by using the auxiliary power supply.
<B. Second Preferred Embodiment>
[0057] FIG. 7 is a block diagram that shows a configuration of an elevator system in accordance
with a second preferred embodiment of the present invention. The elevator system of
the second preferred embodiment further includes a communication controller 1c installed
in an elevating path 23, an elevating path switch 25, a door switch 24 at the platform
and a safety control device 6c in addition to the configuration of the elevator system
2 of the first preferred embodiment.
[0058] In the elevator system of the present preferred embodiment, a communication controller
and a safety control device are installed in each of the control panel 4, the cage
5 and the elevating path 23, and these safety control devices individually carry out
safety controls. At this time, the respective communication controllers 1a, 1b and
1c mutually communicate information of elevator equipments that are respectively connected
thereto so that safety control devices 6a, 6b and 6c that are respectively connected
with the communication controllers 1a, 1b and 1c are allowed to carry out safety controls
while sharing pieces of information of the elevator equipments.
[0059] For example, results of detections from the door switch 24 at a platform and the
elevating path switch 25 are transmitted from the communication controller 1 c installed
at the elevating path, and by allowing these to be received by the communication controller
1b of the cage 5, it is possible to provide such a safety control that an emergency
stop 26 installed in the cage 5 is activated upon detection of an unintended movement
of the cage 5.
[0060] Moreover, by allowing the safety control devices 6a, 6b and 6c to exchange data among
them, mutual monitoring processes are available so that upon occurrence of a failure
in any one of the safety control devices, the movement of the cage 5 can be stopped
by using another safety control device so that a backup operation of safety control
can be executed. That is, in accordance with the present preferred embodiment, it
is possible to further improve the functions of the safety control device upon occurrence
of an abnormal state, while reducing the number of wires of the elevator.
[0061] Additionally, in any of the preferred embodiments, the safety communication unit
35 and the safety signal interface 36 of each of the communication controllers 1a,
1b and 1c may be included in each of the safety control devices 6, 6a, 6b and 6c.
Moreover, information to be added to a safety signal by the safety communication unit
35 may be any information other than CRC codes, and even when parity bits, BCH codes,
Reed-Solomon codes, error-correction codes or the like are used, the same effects
can be obtained.
[0062] While the invention has been shown and described in detail, the foregoing description
is in all aspects illustrative and not restrictive. It is therefore understood that
numerous modifications and variations can be devised without departing from the scope
of the invention.
1. An elevator system comprising:
a first communication controller (1b) that is installed in an elevator cage (5), an
elevating path or a platform, and connected to an elevator equipment inside said elevator
cage (5), an elevator equipment inside said elevating path or an elevator equipment
of said platform;
a second communication controller (1a) that is connected to said first communication
controller (1b) through a serial communication network (2) and an individual communication
line (3) so as to perform communication; and
control means (6, 7) that is connected to said second communication controller (1a)
so as to control operations of said elevator cage (5),
wherein said individual communication line (3) communicates a signal individually
in a manner separated from a signal communicated through said serial communication
network (2).
2. The elevator system according to claim 1, wherein said first and second communication
controllers (1a, 1b) transmit the transmission signal based upon a transmission schedule
in accordance with a precedence degree of a transmission signal in said serial communication
network (2).
3. The elevator system according to claim 1 or 2, wherein said first and second communication
controllers (1a, 1b) perform communication by using said individual communication
line (3) when communication by said serial communication network (2) is impossible.
4. The elevator system according to any one of claims 1 to 3, wherein said first and
second communication controllers (1a, 1b) monitor a communication error of said serial
communication network (2) and determine a schedule for a transmission signal based
upon a frequency of the communication error.
5. The elevator system according to any one of claims 1 to 4, wherein said first and
second communication controllers (1a, 1b) determine a schedule for a transmission
signal based upon a usable bandwidth of a communication path in said serial communication
network (2).
6. The elevator system according to any one of claims 1 to 5, wherein upon communicating
information relating to safety control, said first and second communication controllers
(1a, 1b) add error detection information to the information relating to safety control
at the time of transmitting, and carry out an error detection by using said error
detection information at the time of receiving.
7. The elevator system according to any one of claims 1 to 6, wherein said second communication
controller (1a) determines contents of a communication error and kinds of communication
information upon occurrence of the communication error, and
said control means (6, 7) allows said elevator cage (5) to continue operations, or
brings said elevator cage (5) to a stop at the nearest floor, or to an emergency stop
based upon the determination of said second communication controller (1a).
8. The elevator system according to claim 7, wherein said first communication controller
(1b) transmits contents of a communication error and kinds of communication information
to said second communication controller (1a) by using said individual communication
line (3) upon occurrence of the communication error in said serial communication network
(2).
9. The elevator system according to any one of claims 1 to 6, wherein said first communication
controller (1b) determines contents of a communication error and kinds of communication
information upon occurrence of the communication error in said serial communication
network (2), and based upon the determination, gives an instruction to said second
communication controller (1a) by using said individual communication line (3) so as
to allow said elevator cage (5) to continue operations, or bring said elevator cage
(5) to a stop at the nearest floor, or to an emergency stop, and
said control means (6, 7) allows said elevator cage (5) to continue operations, or
brings said elevator cage (5) to a stop at the nearest floor, or to an emergency stop
based upon said instruction received by said second communication controller (1a)
from said first communication controller (1b).
10. The elevator system according to any one of claims 1 to 7, further comprising:
second control means (6b) that is connected to said first communication controller
(1b) so as to control operations of said elevator cage (5),
wherein said first communication controller (1b) determines contents of a communication
error and kinds of communication information upon occurrence of the communication
error, and
said second control means (6b) allows said elevator cage (5) to continue operations,
or brings said elevator cage (5) to a stop at the nearest floor, or to an emergency
stop based upon the determination of said first communication controller (1b).
11. The elevator system according to any one of claims 1 to 10, further comprising:
an auxiliary power supply (14) for supplying electric power at the time of a power
loss of a main power supply.