Technical Field
[0001] The present invention relates to an elevator apparatus which employs an electronic
safety controller for detecting abnormality of an elevator based on a detection signal
from a sensor.
Background Art
[0002] In conventional elevator safety systems, sensors or the like are connected to bus
nodes provided to a hoistway, a machine room, and a car, allowing information from
the sensors or the like to be sent through the bus nodes and a communication network
bus to a safety controller (see, for example, Patent Document 1).
Disclosure of the Invention
Problems to be solved by the Invention
[0004] In a conventional elevator apparatus constructed as described above, a large number
of communication cables need to be wired within the hoistway, which makes it rather
troublesome to install the elevator apparatus. Further, spaces need to be ensured
within the hoistway for the wiring, which causes an increase in an area of the hoistway.
[0005] The present invention has been made to solve the problems as discussed above, and
it is therefore an object of the invention to obtain an elevator apparatus capable
of alleviating troubles during installation and reducing the spaces within the hoistway.
Means for solving the Problems
[0006] An elevator apparatus according to the present invention includes: a sensor for generating
detection signal for detecting a state of an elevator; and an electronic safety controller
for detecting abnormality of the elevator based on the detection signal from the sensor
and outputting a command signal for shifting the elevator to a safe state, and in
the elevator apparatus, at least part of the detection signal and the command signal
is transmitted through radio communication.
Brief Description of the Drawings
[0007]
[Fig. 1] A structural diagram of an elevator apparatus according to Embodiment 1 of
the present invention.
[Fig. 2] A graph of patterns of overspeed set in speed governor and an ETS circuit
portion of the electronic safety controller of Fig. 1.
[Fig. 3] A block diagram of a device configuration of a main part of the electronic
safety controller of Fig. 1.
[Fig. 4] An explanatory diagram of a method of executing calculation processing by
a microprocessor of Fig. 3.
[Fig. 5] A structural diagram schematically showing an elevator apparatus according
to Embodiment 2 of the present invention.
Best Mode for carrying out the Invention
[0008] Preferred embodiments of the present invention will be hereinafter described with
reference to the drawings.
Embodiment 1
[0009] Fig. 1 is a structural diagram of an elevator apparatus according to Embodiment 1
of the invention. In the drawing, a hoistway 1 includes a pair of car guide rails
(not shown) and a pair of counterweight guide rail (not shown). A car 3 is raised
and lowered in the hoistway 1 while being guided by the car guide rails. A counterweight
4 is raised and lowered in the hoistway 1 while being guided by the counterweight
guide rail.
[0010] Provided in a lower part of the car 3 is a safety device 5 that engages with the
car guide rails to stop the car 3 in case of an emergency. The safety device 5 has
a pair of braking pieces that are moved by mechanical operation to be pushed against
the car guide rails 2.
[0011] In the lower part of the hoistway 1, a driving apparatus (traction machine) 7 that
raises and lowers the car 3 and the counterweight 4 via a main rope 6 is provided.
The driving apparatus 7 has: a drive sheave 8; a motor portion 9 that rotates the
drive sheave 8; a brake portion 10 that brakes the rotation of the drive sheave 8;
and a motor encoder 11 that generates a detection signal according to the rotation
of the drive sheave 8.
[0012] The brake portion 10 is, for example, an electromagnetic brake apparatus. In the
electromagnetic brake apparatus, a spring,force of a braking spring is used to push
a brake shoe against a braking surface to brake the rotation of the drive sheave 8
and an electromagnetic magnet is excited to separate the brake shoe from the braking
surface to cancel the braking.
[0013] An elevator control portion 12 is provided, for example, in a lower part of the hoistway
1. The elevator control portion 12 includes: an operation control portion that controls
operation of the driving apparatus 7; and a safety circuit portion (relay circuit
portion) that suddenly stops the car 3 when the elevator has abnormality. The operation
control portion is input with a detection signal from the motor encoder 11. Based
on the detection signal from the motor encoder 11, the operation control portion calculates
the position and speed of the car 3 to control the driving apparatus 7.
[0014] When the relay circuit of the safety circuit portion is opened, an electric current
to the motor portion of the driving apparatus 7 is blocked and an electric current
to the electromagnetic magnet of the brake portion 10 is also blocked, whereby the
drive sheave 8 is braked.
[0015] In the upper part of the hoistway 1, a speed governor (mechanical speed governor)
14 is provided. The speed governor 14 includes: a speed governor sheave, an overspeed
detection switch, a rope catch, and a speed governor encoder 15 serving as a sensor.
The speed governor sheave is wound at a speed governor rope 16. Both ends of the speed
governor rope 16 are connected to an operational mechanism of the safety device 5.
The lower end of the speed governor rope 16 is wound around a tightening pulley 17
provided in the lower part of the hoistway 1.
[0016] When the car 3 is raised or lowered, the speed governor rope 16 is moved in circulation
and the speed governor sheave is rotated at a rotation speed corresponding to a traveling
speed of the car 3. The speed governor 14 mechanically detects that the traveling
speed of the car 3 reaches an overspeed. Set as overspeeds to be detected are a first
overspeed (OS speed) that is higher than a rated speed and a second overspeed (Trip
speed) that is higher than the first overspeed.
[0017] When the traveling speed of the car 3 reaches the first overspeed, the overspeed
detection switch of the speed governor 14 is operated. When the overspeed detection
switch is operated, the relay circuit of the safety circuit portion of the elevator
control portion 12 is opened. When the traveling speed of the car 3 reaches the second
overspeed, the rope catch of the speed governor 14 grips the speed governor rope 16
to stop the circulation of the speed governor rope 16. When the circulation of the
speed governor rope 16 is stopped; the safety device 5 provides a braking operation.
[0018] The speed governor encoder 15 generates a detection signal according to the rotation
of the speed governor sheave. The speed governor encoder 15 employs a dual sense type
encoder that simultaneously outputs two types of detection signals, i . e. , a first
detection signal and a second detection signal.
[0019] The first detection signal and the second detection signal from the speed governor
encoder 15 are input to an ETS circuit portion of an Emergency Terminal Slowdown apparatus
(ETS apparatus) provided at an electronic safety controller 21. The ETS circuit portion
detects, based on a detection signal from the speed governor encoder 15, abnormality
of an elevator and outputs a command signal for shifting the elevator to a safe state.
More specifically, the ETS circuit portion calculates, independently from the elevator
control portion 12, a traveling speed and a position of the car 3 based on the signal
from the speed governor encoder 15, and monitors whether the traveling speed of the
car 3 in the vicinity of a terminal landing reaches an ETS monitoring overspeed.
[0020] The ETS circuit portion also converts the signal from the speed governor encoder
15 to a digital signal to perform a digital calculation processing and determine whether
the traveling speed of the car 3 reaches an ETS monitoring overspeed. When the ETS
circuit portion determines that the traveling speed of the car 3 has reached the ETS
monitoring overspeed, the relay circuit of safety circuit portion is opened.
[0021] The ETS circuit portion can also detect abnormality of the ETS circuit portion itself
and abnormality of the speed governor encoder 15. When the ETS circuit portion detects
abnormality of the ETS circuit portion itself or abnormality of the speed governor
encoder 15, a nearest floor stop command signal is output from the ETS circuit unit
to the operation control portion as a command signal for shifting the elevator to
a safe state. Interactive communication is also possible between the ETS circuit portion
and the operation control portion.
[0022] In predetermined positions in the hoistway 1, there are provided a first reference
location sensor 23 and a second reference location sensor 24 for detecting that the
car 3 is located at a reference position in the hoistway. Top and bottom terminal
landing switches can be used for the reference location sensors 23 and 24. Detection
signals from the reference location sensors 23 and 24 are input to the ETS circuit
portion of the electronic safety controller 21. Based on the detection signals from
the reference location sensors 23 and 24, the ETS circuit portion corrects information
for the position of the car 3 calculated in the ETS circuit portion.
[0023] Between a bottom face of the hoistway 1 and lower faces of the car 3 and the counterweight
4, a car buffer 27 and a counterweight buffer 28 are provided. Here, the car buffer
27 and the counterweight buffer 28 are provided in the lower part in the hoistway
1. The car buffer 27 is provided just below the car 3 and reduces an impact caused
when the car 3 collides with a bottom part of the hoistway 1. The counterweight buffer
28 is provided just below the counterweight 4 and reduces an impact caused when the
counterweight 4 collides with a bottom part of the hoistway 1. These buffers 27 and
28 may be, for example, an oil-filled-type or spring-type buffer.
[0024] A pair of car suspending pulleys 41a and 41b are provided in a lower part of the
car 3. A counterweight suspending pulley 42 is provided in an upper part of the counterweight
4. Car-side return pulleys 43a and 43b and a counterweight-side return pulley 44 are
disposed in the upper part of the hoistway 1. The main rope 6 has a first end 6a and
a second end 6b, which are connected to a top portion of the hoistway 1 via rope stop
portions.
[0025] The main rope 6 is wound, sequentially from the first end 6a side, around the car
suspending pulleys 41a and 41b, the car-side return pulleys 43a and 43b, the drive
sheave 8, the counterweight-side return pulley 44, and the counterweight suspending
pulley 42. That is, in this example, the car 3 and the counterweight 4 are suspended
within the hoistway 1 according to a 2:1 roping method.
[0026] The motor encoder 11, the elevator control portion 12, the speed governor encoder
15, the electronic safety controller 21, and the reference location sensors 23 and
24 are each provided with a communication portion (an antenna portion) for transmitting
a signal through radio communication (e.g., locale area wireless network communication)
. Arrows of broken lines in Fig. 1 indicate radio communication.
[0027] More specifically, a detection signal of the motor encoder 11 is sent to the elevator
control portion 12 through radio communication. Information transmission between the
electronic safety controller 21 and the elevator control portion 12 is performed through
radio communication. A nearest floor stop command issued from the electronic safety
controller 21 to the elevator control portion 12 is transmitted through radio communication.
However, an emergency stop command issued from the electronic safety controller 21
to the safety circuit portion of the elevator control portion 12 is transmitted through
a communication cable (an arrow of a solid line in Fig. 1). Although not shown, an
emergency stop command issued from the speed governor 14 to the safety circuit portion
is also transmitted through a communication cable. A detection signal of the speed
governor encoder 15 and detection signals from the reference location sensors 23 and
24 are sent to the electronic safety controller 21 through radio communication.
[0028] In this example, one signal is transmitted using a plurality of different carrier
frequencies. In other words, the adoption of multiplex communication enhances reliability.
[0029] Furthermore, operation modes of the electronic safety controller 21 include a plurality
of modes such as, for example, a normal operation mode, a maintenance operation mode,
an emergency operation mode, and the like. Mode information in the electronic safety
controller 21 is transmitted to the elevator control portion 12 through radio communication.
[0030] Fig. 2 is a graph of overspeed patterns set in the speed governor 14 and the ETS
circuit portion of the electronic safety controller 21 of Fig. 1. In the drawing,
when the car 3 travels at a normal speed (rated speed) from a bottom terminal landing
to a top terminal landing, the car 3 draws a normal speed pattern V0. A first overspeed
pattern V1 and a second overspeed pattern V2 are set in the speed governor 14 by a
mechanical position adjustment. An ETS monitoring overspeed pattern VE is set in the
ETS circuit portion.
[0031] The ETS monitoring overspeed pattern VE is set to be higher than the normal speed
pattern V0. The ETS monitoring overspeed pattern VE is also set to have equal intervals
from the normal speed pattern V0 in the entire raising/lowering process. In other
words, the ETS monitoring overspeed pattern VE changes according to a car position.
More specifically, the ETS monitoring overspeed pattern VE is set to be held constant
in the vicinity of an intermediate floor, and is set to continuously and smoothly
decline in the vicinity of a terminal landing, as ends (upper end and lower end) of
the hoistway 1 become closer. In this manner, the ETS circuit portion monitors the
traveling speed of the car 3 not only in the vicinity of a terminal landing but also
in the vicinity of an intermediate floor (a fixed speed traveling zone in the normal
speed pattern V0). However, the ETS circuit portion does not always have tomonitor
the traveling speed of the car 3 in the vicinity of the intermediate floor.
[0032] The first overspeed pattern V1 is set to be higher than the ETS monitoring overspeed
pattern VE. The second overspeed pattern V2 is set to be further higher than the first
overspeed pattern V1. The first overspeed pattern V1 and the second overspeed pattern
V2 are fixed at all heights in the hoistway 1.
[0033] Fig. 3 is a block diagram of a device configuration of a main part of the electronic
safety controller 21 of Fig. 1. The electronic safety controller 21 includes: a first
microprocessor 31 that performs calculation.processing for detecting abnormality of
the elevator based on a first safety program; and a second microprocessor 32 that
performs calculation processing for detecting abnormality of the elevator based on
a second safety program.
[0034] The first safety program is a program that has the same content as that of the second
safety program. The first microprocessor 31 and the second microprocessor 32 are capable
of mutual communication via an interprocessor bus and a dual port RAM 33. The first
microprocessor 31 and the second microprocessor 32 can also check the soundness of
the first microprocessor 31 and the second microprocessor 32 themselves by mutually
comparing the results of the calculation processing. In other words, the soundness
of the first microprocessor 31 and the second microprocessor 32 is checked by causing
the first microprocessor 31 and the second microprocessor 32 to perform identical
processing, and communicating and comparing the processing results via the dual port
RAM 33 or the like.
[0035] In addition to the abnormality of the microprocessors 31 and 32 themselves, the microprocessors
31 and 32 can also detect abnormality of the electronic-safety controller 21 by calculation
processing.
[0036] Fig. 4 is an explanatory diagram of a method of performing calculation processing
by the microprocessors 31 and 32 of Fig. 3. The microprocessors 31 and 32 repeatedly
perform calculation processing with a predetermined computation cycle (e.g., 50 msec)
based on a signal from a fixed-cycle timer and according to a program stored in a
ROM. A program executed in one cycle includes a safety program for detecting abnormality
of an elevator and a failure/abnormality check program for detecting the failure/abnormality
of the electronic safety controller 21 itself and various sensors. The failure/abnormality
check program can be set to be executed only when predetermined states are satisfied.
[0037] In the failure/abnormality check program, for example, detection of clock abnormality,
detection of abnormality in a stack region of the RAM, detection of abnormality in
a sequence of calculation processings, detection of abnormality in a relay contact,
detection of abnormality in power supply voltage, and the like are carried out.
[0038] In the elevator apparatus, the electronic safety controller 21 can detect abnormality
of the electronic safety controller 21 itself and outputs a command signal for shifting
the elevator to a safe state even when abnormality of the electronic safety controller
21 itself is detected. Thus, a relatively simple structure can be used to improve
the reliability of a safety system while improving a speed to detect abnormality of
an elevator and a speed of the processing for the abnormality.
[0039] The electronic safety controller 21 can also detect abnormality of various sensors
and can output a command signal for shifting the elevator to a safe state even when
abnormality of the sensor is detected. Thus, the safety system can have a further
improved reliability.
[0040] Furthermore, the electronic safety controller 21 includes first microprocessor 31
and the second microprocessor 32. The first microprocessor 31 and the second microprocessor
32 can check the soundness of the first microprocessor 31 and the second microprocessor
32 themselves by mutually comparing results of calculation processing. Thus, the safety
system can have a further improved reliability.
[0041] Still further, in this elevator apparatus, transmission of at least part of the detection
signals from sensors for detecting a state of the elevator (the speed governor encoder
15 and the reference location sensors 23 and 24 in this case) and command signals
from the electronic safety controller 21 for shifting the elevator to a safe state
is performed through radio communication. Thus, there is no need to dispose a large
number of communication cables within the hoistway 1 in a complicated manner, making
it possible to alleviate troubles during installation and reduce spaces within the
hoistway 1. Especially in the case of an electronic safety monitoring system, where
many and various signals are transmitted and transmission paths are complicated, transmission
of signals regarding the electronic safety controller 21 through radio communication
is effective.
[0042] Further, in this elevator apparatus, detection signals from the motor encoder 11
and signals between the elevator control portion 12 and the electronic safety controller
21 are also transmitted through radio communication. Accordingly, it is possible to
further alleviate the troubles during installation and further reduce the spaces within
the hoistway 1.
[0043] In addition, the electronic safety controller 21 transmits a command signal for stopping
the car 3 at a nearest floor through radio communication and transmits a command signal
through cable communication to bring the car 3 to an emergency stop, thereby making
it possible to ensure higher reliability.
[0044] Although the single elevator apparatus has been described in the foregoing example,
signals from sensors of a plurality of elevator apparatuses located in the same building
may be managed by a common electronic safety controller. Also in this case, the same
effect as in the foregoing example can be achieved by transmitting detection signals
and command signals through radio communication.
Although the speed governor encoder 15 and the reference location sensors 23 and 24
are mentioned as the sensors for sending detection signals to the electronic safety
controller 21 in the foregoing example, the sensors should not be limited to the aforementioned
ones. For instance, detection signals from various sensors such as a temperature sensor,
a speed sensor, an acceleration sensor, a vibration sensor, and the like can be transmitted
through radio communication.
Further, it is not necessary to transmit detection signals from all the sensors through
radio communication. It is also appropriate to transmitdetectionsignalsfrom onlyselectedsensors
through radio communication.
Still further, it is not necessary either to transmit all the command signals from
the electronic safety controller 21 through radio communication. On the contrary,
it is also appropriate to transmit all the command signals including emergency stop
commands through radio communication.
Embodiment 2
[0045] Next, Fig. 5 is a schematic diagram showing an elevator apparatus according to Embodiment
2 of the present invention. A first car 3a and a second car 3b are provided within
the hoistway 1. The first car 3a and the second car 3b, which are arranged in a vertically
aligned manner, are raised/lowered within the common hoistway 1 independently from
each other. In other words, this elevator apparatus is a one-shaft multi-car type
elevator. Accordingly, the first car 3a is raised/lowered by a first drive device
(not shown), and the second car 3b is raised/lowered by a second drive device (not
shown). A main rope and the like for suspending the first car 3a and the second car
3b are not illustrated.
[0046] The first car 3a and the second car 3b are each provided with a communication portion
(an antenna portion) for transmitting signals (a request signal for a call registration,
a confirmation signal for a call registration, and the like) to/from the elevator
control portion 12 (Fig. 1) through radio communication. Other components are identical
to those of Embodiment 1.
[0047] In the elevator apparatus constructed as described above, signals between the cars
3a and 3b and the elevator control portion 12 as well as signals regarding the electronic
safety controller 21 (Fig. 1) are transmitted through radio communication. It is therefore
possible to alleviate troubles during installation and reduce the spaces within the
hoistway 1. That is, in a conventional one-shaft multi-car type elevator, two communication
cables need to be connected to two cars respectively in such a manner as not to interfere
with each other, which leads to a difficulty in layout and an increase in the spaces
within a hoistway. However, according to Embodiment 2, it is possible to reduce the
space of the hoistway 1.
[0048] Although Embodiment 2 deals with a one-shaft multi-car type elevator, the car 3 of
the elevator apparatus according to Embodiment 1 of the present invention may be provided
with a communication portion so that signals are transmitted between the car 3 and
the elevator control portion 12 through radio communication.
Although an emergency stop command from the electronic safety controller 21 is input
to the safety circuit portion of the elevator control portion 12 in the foregoing
example, a safety circuit portion for the electronic safety controller 21 may be provided
separately from the safety circuit portion of the elevator control portion 12 so that
an emergency stop command from the electronic safety controller 21 is input to the
safety circuit portion for the electronic safety controller 21.
1. An elevator apparatus, comprising:
a sensor for generating detection signal for detecting a state of an elevator; and
an electronic safety controller for detecting abnormality of the elevator based on
the detection signal from the sensor and outputting a command signal for shifting
the elevator to a safe state,
wherein, at least part of the detection signal and the command signal is transmitted
through radio communication.
2. The elevator apparatus according to Claim 1, further comprising an elevator control
portion for controlling operation of a car,
wherein, the sensor, the electronic safety controller, and the elevator control portion
are provided respectively with communication portions for transmitting signals thereamong
through radio communication.
3. The elevator apparatus according to Claim 1, wherein the electronic safety controller
transmits a command signal for stopping the car at a nearest floor through radio communication
and transmits a command signal for bringing the car to an emergency stop through cable
communication.
4. The elevator apparatus according to Claim 1, wherein the electronic safety controller
can detect abnormality in the electronic safety controller itself and outputs a command
signal for shifting the elevator to a safe state also when detecting the abnormality
in the electronic safety controller itself.
5. The elevator apparatus according to Claim 1, wherein the electronic safety controller
can detect abnormality in the sensor and outputs a command signal for shifting the
elevator to a safe state also when detecting abnormality in the sensor.
6. The elevator apparatus according to Claim 1, wherein:
the electronic safety controller includes a first microprocessor for performing a
calculation processing for detecting abnormality in the elevator based on a first
safety program, and a second microprocessor for performing a calculation processing
for detecting abnormality in the elevator based on a second safety program; and
the first microprocessor and the second microprocessor, which are capable of mutual
communication via an interprocessor bus, and capable of checking soundness of the
first microprocessor and the second microprocessor themselves by mutually comparing
results of the calculation processing.
7. The elevator apparatus according to Claim 1, further comprising an elevator control
portion for controlling operation of the car,
wherein, the car and the elevator control portion also transmit signals to each other
through radio communication.