JP2013020421A - Traffic signal controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a traffic signal controller that can reduce power consumption required for communication with a central device.SOLUTION: The invention relates to a traffic signal controller 1 for controlling the light color switching timing of a signal light device. The traffic signal controller 1 includes a communication unit 2 that communicates with a central device 6, and a control unit 3 (CPU31) that suppresses or stops power supply to the communication unit 2 except for the communication time Tc required for exchanging predetermined information with the central device 6.

Description

  The present invention relates to a traffic signal controller that controls lighting or extinguishing of a signal lamp. More specifically, the present invention relates to a measure for power saving of the traffic signal controller.

At an intersection or pedestrian crossing, a traffic signal controller is installed to control the lighting or extinguishing of the blue, yellow, red, and blue arrows of the signal lamp at predetermined time intervals.
Such traffic signal controllers include “centralized type” and “point type”. Among these, the centralized traffic signal controller has a function of performing information communication with a central device installed in a traffic control center or the like, and the point type traffic signal controller is connected to the central device. The signal lamp is controlled independently without performing the above communication.

Of the above traffic signal controllers, the centralized traffic signal controller is connected to the central unit via a communication line such as a telephone line and is centrally controlled according to signal control commands from the central unit. There are two types of centralized control, “step control” and “table control”.
Of these, step control uses D-type transmission, T-type transmission, or M-type transmission, and is a control method that advances the floor based on step information transmitted by the central device in a short cycle (for example, every second). .

On the other hand, the table control uses U-type transmission or UD-type transmission, and the traffic signal controller determines the time of each step based on the signal control command transmitted regularly or irregularly from the central unit. It is a control method that decides and advances the floor.
In this case, since the traffic signal controller advances the floor based on the table specified by the central device, the central device determines the cycle length, offset and split, and the traffic signal controller uses these determined parameters. The time of a floor is calculated | required (refer nonpatent literature 1).

FIG. 7 is a sequence diagram of communication frames transmitted and received between the central apparatus and a conventional traffic signal controller in the case of table control.
As shown in FIG. 7, the traffic signal controller transmits “signal control execution information” storing control contents such as offset time executed in the previous cycle to the central unit at the start of this cycle, At a proper time (in the middle of step 1 in the figure), a “signal control command” including a signal control parameter used in the next cycle is received from the central device.

Conventionally, in addition to the exchange of the signal control execution information and the signal control command, the “step information” (K1 to K10) storing the step number i (i = 1 to 10) is advanced by one step (step). Each time, the traffic signal controller transmits to the central device, and notifies the central device of the progress of the floor.
Furthermore, in the past, by sending a “confirmation signal” (virtual line arrow in FIG. 7) with empty data content to the central device between transmissions of the floor information K1 to K10, the connection state with the traffic signal controller The central unit is constantly monitoring.
In addition, in the example of FIG. 7, the case of a standard 10-story is illustrated, but when further including other floors such as “right turn blue”, the floor information transmitted by the traffic signal controller accordingly. Will increase.

"Revised Traffic Signal Guide" Editorial and publication Traffic Engineering Research Group (pages 96-98)

By the way, there is a need to reduce the amount of commercial power used as much as possible in the time zone when the power demand is large, such as in the daytime in summer, for example, against the background of the recent deterioration of the power situation.
In this regard, in the case of a traffic signal controller, since power supply to the signal lamp cannot be stopped from the viewpoint of ensuring traffic safety, the power consumption in the communication unit of the centralized traffic signal controller is reduced. If possible, it is considered that this contributes to power saving for the entire traffic signal control system under the jurisdiction of the central unit.

  However, as described above, in the communication between the conventional central device and the traffic signal controller, the floor information (K1 to K10 in FIG. 7) in the current cycle is transmitted to the central device every time the floor is switched, or the line A confirmation signal for confirmation is sent to the central unit, so it is not possible to secure enough time to rest the communication unit in one cycle, and reduce the power consumption required for traffic signal controller communication I could not.

  That is, in the conventional traffic signal controller, the floor information and the confirmation signal are frequently transmitted to the central device, so that the period during which no signal is transmitted is very short. For this reason, if the power supply to the communication unit is stopped or the operation is shifted to the sleep operation to suppress the power supply, a certain amount of time is required for re-establishing the communication line for the next communication, and the period during which no signal is transmitted is If it is not longer than the time, it is not possible to stop power feeding or to suppress power feeding of the communication unit.

  The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a traffic signal controller capable of reducing power consumption required for communication with a central device.

  (1) The traffic signal controller of the present invention is a traffic signal controller that controls the timing for switching the color of a signal lamp, and exchanges predetermined information between a communication unit that communicates with a central device and the central device. And a control unit that suppresses or stops power supply to the communication unit except for a communication time necessary for the communication.

According to the traffic signal controller of the present invention, the control unit suppresses or stops power supply to the communication unit except for the communication time necessary for exchanging predetermined information with the central device. Power consumption required for communication can be reduced.
For this reason, the plurality of traffic signal controllers constituting the traffic signal control system can reduce the power consumption required for communication, thereby reducing the power consumption of the entire system.

(2) In the traffic signal controller of the present invention, the communication time includes a preparation time required for establishing a line with the central device and an actual operation time after the establishment.
The reason for this is that once the power supply to the communication unit has been suppressed or stopped, it is necessary to send and receive a predetermined communication frame to and from the central unit and establish a line with the central unit. This is because the communication unit cannot transmit the necessary information to the central apparatus or receive the necessary information from the central apparatus.

(3) In the traffic signal controller of the present invention, the predetermined information includes, for example, a signal control command that the central device transmits to the communication unit in order to notify the traffic signal controller of signal control parameters. It is.
This is because the signal control parameters (cycle length, split, and offset) included in the signal control command are indispensable information for the centralized traffic signal controller that performs table control.

(4) In addition, the predetermined information includes signal control execution information that the communication unit transmits to the central device in order to notify the central device of the control content actually performed by the traffic signal controller. It may be.
The signal control execution information includes the control content actually performed by the traffic signal controller (for example, the offset time actually executed, the number of seconds of each floor, and the sensing information). This is because the information is necessary for traffic signal control performed by the central device.

(5) Furthermore, the predetermined information may include emergency information that the communication unit transmits to the central device so that the traffic signal controller notifies the central device of an emergency.
The emergency information is important information for notifying an emergency situation (for example, blue / blue detection or timer abnormality) that has occurred in the traffic signal controller, and such important information is intended to reduce power consumption in the communication unit. This is because the central device should be preferentially notified.

  (6) In the traffic signal controller according to the present invention, for example, the predetermined information is included in a predetermined command (the signal control command or another command may be used) transmitted from the central device to the communication unit. When a region for specifying a reception cycle when the communication unit receives is included, the control unit suppresses or stops power supply to the communication unit according to the value of the reception cycle included in the command. What is necessary is just to determine a belt.

(7) In the traffic signal controller of the present invention, the predetermined command transmitted from the central unit to the communication unit includes an area for designating a transmission cycle when the communication unit transmits the predetermined information. If so, the control unit may determine a time period during which power supply to the communication unit is suppressed or stopped according to the value of the transmission cycle included in the command.
In this case, since the time zone for suppressing or stopping the power supply of the communication unit is determined in accordance with the reception cycle and transmission cycle specified by the central device, the setting of the time zone for the traffic signal controller is controlled centrally from the central device. Can be done by.

(8) Moreover, in the traffic signal controller of the present invention, the predetermined command transmitted from the central unit to the communication unit includes an area for designating an operation mode for the communication unit, and the control unit When the operation mode specified by the command is a power saving mode, it is preferable to perform a power saving operation that repeats the time period during which the power supply to the communication unit is suppressed or stopped and the communication time.
In this way, it is possible to shift the traffic signal controller to the above power saving operation according to an instruction from the central device, and the centralized control from the central device also for each traffic signal controller to shift to the power saving operation. It becomes possible to set by.

  (9) In this case, an area for designating the value of the duration of the power saving operation is included in the command, and the control unit continues the power saving operation according to the value of the duration included in the command. By doing so, the duration of the power saving operation to be performed by each traffic signal controller can also be set by centralized control from the central device.

(10) As described above, in the traffic signal controller of the present invention, the control unit suppresses or stops power supply to the communication unit except for the communication time necessary for exchanging predetermined information with the central device.
When the power control for such a communication unit is expressed from another viewpoint, focusing on the difference from the conventional table control (FIG. 7), the control unit displays the floor information indicating the transition of the floor in one cycle. The transmission to the apparatus is stopped, and the power supply to the communication unit is suppressed or stopped during the period in which the transmission is stopped.

  That is, the traffic signal controller of the present invention viewed from another point of view is a traffic signal controller that controls the timing of switching the color of a signal lamp, and includes a communication unit that communicates with a central device and a floor in one cycle. A control unit for stopping or stopping power supply to the communication unit during a period in which the communication unit stops transmitting all or part of the floor information indicating a transition to the central device, and the transmission is stopped; It is characterized by having.

  According to the traffic signal controller of the present invention viewed from another viewpoint, the control unit stops the communication unit from transmitting all or part of the floor information indicating the transition of the floor in one cycle to the central device. Therefore, it is possible to secure a sufficient time to rest the communication unit, and the control unit suppresses or stops the power supply to the communication unit during the period when the transmission is stopped. Power consumption required for communication can be reduced.

  As described above, according to the present invention, the traffic signal controller can reduce the power consumption necessary for communication with the central device, which can contribute to the power saving of the traffic signal control system managed by the central device.

It is a block diagram which shows the structural example of the traffic signal controller which concerns on this invention. It is a block diagram which shows the structural example of a central apparatus. It is a table | surface which shows the example of the content of the signal control command which a central apparatus produces | generates. It is a table | surface which shows the example of the content of the signal control execution information which a traffic signal controller produces | generates. It is a sequence diagram of the communication frame transmitted / received between a central apparatus and a traffic signal controller. It is another sequence diagram of the communication frame transmitted / received between a central apparatus and a traffic signal controller. It is a sequence diagram of the communication frame transmitted / received between a central apparatus and the conventional traffic signal controller in the case of table control.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Configuration of traffic signal controller]
FIG. 1 is a block diagram showing a configuration example of a traffic signal controller 1 according to the present invention.
The traffic signal controller 1 of the present embodiment is a centralized type and table control type, and includes a communication unit 2, a control unit 3, a power supply unit 4, a blue-blue detection circuit 10, and a lamp drive unit 11. In FIG. 1, only one lamp driving unit 11 that drives the signal lamp 51 is illustrated, but a plurality of actual lamp driving units 11 are provided according to the number of signal lamps 51.

The traffic signal controller 1 includes an ultrasonic sensor interface unit 12, an image sensor interface unit 13, a traffic information board interface unit 14, a push button device as various interface units for exchanging signals with external devices. An interface unit 15 and a traffic signal controller interface unit 16 are provided.
Further, the communication unit 2 includes a transmission / reception unit 21 and a communication control unit 22, and the control unit 3 includes a CPU 31, a security operation circuit 32, and a flash operation circuit 33.

A central device 6 (also referred to as a traffic control device) installed in the traffic control center is connected to the communication unit 2 of the traffic signal controller 1 through a predetermined communication line. The central device 6 may be installed in a building other than the traffic control center.
The central device 6 is connected to a plurality of centralized traffic signal controllers 1 in the jurisdiction area of the own device through a communication line. A traffic signal control system of the form is configured.

The transmission / reception unit 21 of the communication unit 2 includes a communication interface that performs U-type transmission and UD-type transmission, and transmits predetermined information to and from the central device 6 through wired communication using a communication line or wireless communication using the antenna 2a. Communicate.
That is, in addition to the wired communication function with the central apparatus 6, the transmission / reception unit 21 uses the mobile communication network or the ITS communication network for backup when the communication line cannot be used during a disaster or the like. You can communicate with.

The communication control unit 22 is a processing unit for a communication frame transmitted and received by the transmission / reception unit 21, and includes, for example, “signal control including signal control parameters including cycle length, offset, and split necessary for traffic signal control performed by the own device. When the transmission / reception unit 21 receives “command” or traffic information provided to the vehicle side by the traffic information board 54, the information is passed to the CPU 31 of the control unit 3.
The communication control unit 22 also includes “signal control execution information” (hereinafter also simply referred to as “execution information”) including the time when the signal lamp 51 is actually turned on / off, the sensing signal acquired by the vehicle detector 52, and the like. Is received from the CPU 31 of the control unit 3, the information is transmitted to the transmission / reception unit 21.

The communication control unit 22 according to the present embodiment can execute the “sleep mode” according to the control signals Sa and Sb output from the CPU 31 of the control unit 3.
That is, when the communication control unit 22 receives the sleep start control signal Sa from the CPU 31 of the control unit 3, the communication control unit 22 sets the voltage supplied to the transmission / reception unit 21 and itself to a predetermined value equal to or lower than the operable value and enters the sleep state. When the sleep end control signal Sb is received from the CPU 31, the supply voltage is returned to the normal voltage value to return to the awake state.

A commercial power supply 7 (for example, AC 100V AC power supply) is connected to the power supply unit 4 of the traffic signal controller 1.
The lamp driver 11 is connected to a plurality of signal lamps 51 that give the right of traffic to the inflowing vehicles at the intersection. The interface units 12 to 16 of the traffic signal controller 1 are connected to the ultrasonic vehicle detector 52, An image processing type vehicle sensor 53, a traffic information board 54, a push button device 55, and another traffic signal controller 101 are connected to each other.

[Control part of traffic signal controller]
Among the components of the control unit 3, the CPU 31 includes a programmable arithmetic device, and executes a computer program stored in a storage device (not shown) such as a memory or HDD, thereby switching the color of the signal lamp 51. Timing can be generated.
For example, the CPU 31 determines switching timing such as lighting or extinguishing of the signal lamp 51 for each cycle based on the signal control parameter acquired from the central device 6 received by the communication unit 2, and uses the timing signal as the lamp driving unit. 11 is output.

In addition, the CPU 31 autonomously generates a signal control parameter based on the sensing signal acquired by the vehicle detectors 52 and 53, and sets a switching timing for turning on or off the signal lamp 51 based on the generated signal control parameter. It can also be determined for each cycle.
Furthermore, when a predetermined switching pattern set in advance is recorded in the storage device, the CPU 31 can determine the switching timing for turning on or off the signal lamp 51 from the pattern read from the storage device. .

Further, the CPU 31 can exchange data such as traffic information and sensing signals with each of the interface units 12 to 16 connected to the internal bus 5.
When the CPU 31 stops its own operation and operates the operation circuits 32 and 33 in the control unit 3, it outputs a CPU stop signal to the security operation circuit 32 and the flash operation circuit 33.
On the other hand, the security operation circuit 32 and the flash operation circuit 33 are composed of wired logic control circuits, and perform a single operation assumed in advance (in this case, a security operation or a flash operation).

That is, the security operation circuit 32 is composed of, for example, a logic circuit using a small-scale LSI, and generates a timing signal for switching the color of the signal lamp 51 in place of the CPU 31 when receiving a CPU stop signal. A signal is output to the lamp drive unit 11.
More specifically, the safety operation circuit 32 is configured in hardware so that fixed switching is performed so that the red lamp, the blue lamp, and the yellow lamp of the signal lamp 51 are turned on at a predetermined cycle. The security operation circuit 32 does not output a timing signal when the CPU 31 operates.

Further, the flashing operation circuit 33 is composed of, for example, a logic circuit using an LSI smaller than the security operation circuit 32. When the operations of the CPU 31 and the security operation circuit 32 are stopped, a predetermined signal lamp 51 is substituted for them. A timing signal for blinking the lamp color is generated, and the timing signal is output to the lamp drive unit 11.
More specifically, the flash operation circuit 33 is configured in hardware so that a timing signal for blinking the red lamp of the signal lamp 51 or blinking the yellow lamp is generated.

  In this case, for example, the signal light device 51 on the main line side blinks a yellow light, and the signal light device 51 on the non-main line side blinks a red light. The flash operation circuit 33 does not output a timing signal when the CPU 31 or the security operation circuit 32 operates.

[Sleep control by CPU, etc.]
The CPU 31 of the present embodiment has a sleep control function for the communication unit 2 in addition to the various control functions described above.
That is, the CPU 31 determines a time zone in which the communication unit 2 is to sleep according to a predetermined communication frame Sd acquired from the central device 6 (see FIG. 5 and FIG. 6: a signal control command in the present embodiment), and the determined time zone. The control signal Sa for starting sleep is output to the communication control unit 22 at the start of the time period.

Specifically, the signal control command Sd sent by the central device 6 includes fields defining “reception period” and “transmission period” as seen from the traffic signal controller 1 (see FIG. 3). The CPU 31 determines the timing of outputting the sleep start or end control signals Sa and Sb to the communication control unit 22 using the value of the cycle specified by the signal control command Sd.
A more specific method for determining the timing of outputting the sleep start or sleep end control signals Sa and Sb will be described later.

Further, the CPU 31 has a function of detecting a relatively severe abnormality that has occurred in the traffic signal controller 1. This abnormality includes “blue-blue abnormality”, “timer abnormality”, and “manual stepping”.
Among these, the blue-blue anomaly is an abnormal state in which the signal lamp 51 that gives the right to pass to each of the intersecting roads is simultaneously blue. The blue-blue detection circuit 10 in FIG. 1 is a circuit that outputs a signal when the output voltage of the blue light of each lamp driving unit 11 on the crossing road is detected at the same time, and the CPU 31 determines whether or not there is an output signal of this circuit 10. Based on this, a blue-blue anomaly is detected.

The timer abnormality is an abnormal state of a timer built in the control unit 3. For example, when the security operation by the security operation circuit 32 is not performed as desired and the flashing operation is performed because the same step (floor) has been performed for more than 110 seconds, the CPU 31 starts based on the start of the flashing operation. Detect timer error.
Furthermore, in the traffic signal controller 1 according to the present embodiment, the police officer or the worker can manually control the stepping of the lamp driving unit 11 by operating a push button (not shown). Manual operation can be detected when the switch to manual stepping is turned on.

[Traffic signal controller lamp drive unit and interface unit]
The lamp drive unit 11 includes a plurality of semiconductor relays (not shown) inside. When this relay is turned on, the power supply voltage of AV 100 V supplied from the power supply unit 4 is applied to the signal lamp 51, and the signal lamps of the respective colors such as the red lamp, the blue lamp, and the yellow lamp of the signal lamp 51 are turned on.
The on / off operation of the semiconductor relay is performed by a timing signal output from the CPU 31, the security operation circuit 32, or the flash operation circuit 33 in the control unit 3.

The ultrasonic sensor interface unit 12 acquires a sensing signal (for example, an on signal when the vehicle is detected and an off signal when the vehicle is not detected) from the ultrasonic vehicle sensor 52.
The image sensor interface unit 13 transmits and receives data to and from the image processing vehicle sensor 53. For example, the image picked up by the image processing type vehicle sensor 53 is processed and the processed data is received, and a command signal to the image processing type vehicle sensor 53 is transmitted.
The traffic information board interface unit 14 transmits data for displaying various traffic information on the traffic information board 54.

The push button device interface unit 15 receives an operation signal from the push button device 55 operated by the pedestrian to turn on the blue light of the pedestrian signal lamp.
The traffic signal controller interface unit 16 transmits / receives data to / from other traffic signal controllers 101. For example, when the traffic signal controller 1 controls the lighting, extinguishing, and blinking of the signal lamp 51 as a master unit, the traffic light controller 1 is connected to other points separated from each other according to the lighting time or lighting cycle of each signal lamp of the signal lamp 51. By transmitting necessary data to another traffic signal controller (slave unit) that controls the signal lamp, it is possible to realize a smooth traffic flow between other points.

[Power supply for traffic signal controller]
The power supply unit 4 includes an AC / DC conversion circuit inside.
For the lamp drive unit 11 that operates with an AC power source, the power source unit 4 supplies AC 100V AC of the commercial power source 7 as it is, and other devices that operate with a DC power source, that is, the communication unit 2, the CPU 31, and a safety operation circuit. 32, the flash operation circuit 33, and each of the interface units 12 to 16 are supplied with a DC voltage obtained by rectifying AC 100V AC with an AC / DC conversion circuit.

[Configuration of central unit]
FIG. 2 is a block diagram illustrating a configuration example of the central device 6.
As shown in FIG. 2, the central device 6 includes a control unit 61, a display unit 62, a communication unit 63, a storage unit 64, and an operation unit 65.
In this specification, in order to distinguish from the “control unit 3” and the “communication unit 2” of the traffic signal controller 1, the “control unit 61” of the central device 6 is referred to as “central control unit 61”, and the central device 6 of FIG. The “communication unit 63” may be referred to as a “central communication unit 63”.

The central control unit 61 includes a workstation (WS), a personal computer (PC), and the like, and comprehensively collects, processes (calculates) and records various traffic information from the traffic signal controller 1, controls signals, and provides information. To do.
The central control unit 61 is connected to the hardware units via an internal bus, and also controls the operations of these units.

The central control unit 61 extends “system control” for adjusting the color switching timing of the traffic signal group on the same road to the traffic signal controller 1 belonging to its own jurisdiction area, and extends this system control to the road network. "Wide area control (surface control)" can be executed.
That is, the central control unit 61 can perform traffic sensitivity control that sets signal control parameters (cycle length, split, and offset) according to traffic conditions. The traffic sensitive control performed by the central control unit 61 includes a plurality of types including MODERATO control and profile control, for example.

The central communication unit 63 is a communication interface connected to the communication unit 2 of the traffic signal controller 1 via a communication line, but also has a function of performing wireless communication with the communication unit 2 via a mobile communication network or an ITS communication network. Have.
The central communication unit 63 transmits a signal control command Sd including signal control parameters and the like to each traffic signal controller 1. The signal control command Sd is normally transmitted every signal control parameter calculation cycle (for example, 1.0 to 2.5 minutes). In the present embodiment, a preset “reception cycle” (see FIG. 3). : Transmission cycle).

The display unit 62 of the central device 6 is configured by a display screen on which a road map of the jurisdiction area of the own device and positions of various roadside sensors such as all signal lamps 51 and vehicle detectors on the road map are displayed. Inform the central operator of traffic conditions such as traffic jams and accidents.
The operation unit 65 of the central device 6 includes an input interface such as a keyboard and a mouse. The operation unit 65 allows the central operator to perform a display switching operation on the display unit 62.

  The storage unit 64 of the central device 6 includes an HDD, a semiconductor memory, and the like, and stores a control program for the above-described traffic sensitivity control, a calculation program for a traffic index used for the traffic sensitivity control, and the like. It also has a temporary storage area for signal control commands and traffic information generated by the central control unit 61.

[Contents of signal control command]
FIG. 3 is a table showing a content example of the signal control command Sd generated by the central device 6.
As shown in FIG. 3, the signal control command Sd includes fields (storage area) such as “signal control parameter”, “reception period”, “transmission period”, “used line”, “operation mode”, and “duration”. )It is included.
Of the above fields, the “signal control parameter” includes “cycle length”, “split”, and “offset”, the cycle length is a predetermined number of seconds, and the split is determined by the direction of the intersection. A predetermined second value is written in the percentage value and offset.

The “reception period” is a field in which a period when the traffic signal controller 1 receives a signal control command Sd (see FIG. 5 and FIG. 6) transmitted by the central device 6 in the downstream direction is expressed in seconds.
That is, the central device 6 transmits a signal control command Sd to the traffic signal controller 1 for each second value designated by the reception cycle. In the example of FIG. 3, since the reception cycle is 300 seconds, the central device 6 transmits a signal control command Sd every 300 seconds, and the traffic signal controller 1 sends the signal control command Sd every 300 seconds. Receive.

The “transmission cycle” is a field in which the transmission cycle when the traffic signal controller 1 transmits the signal control execution information Su (see FIG. 5 and FIG. 6) in the numerical value in seconds.
That is, the traffic signal controller 1 transmits the execution information Su to the central device 6 for every second numerical value specified by the transmission cycle. In the example of FIG. 3, since the transmission cycle is also 300 seconds, the traffic signal controller 1 transmits the execution information Su every 300 seconds, and the central device 6 receives the execution information Su every 300 seconds. .

The “used line” is a field for designating a line used for communication between the central device 6 and the traffic signal controller 1 for the traffic signal controller 1 corresponding to both wired and wireless. Either wired or wireless is set in this field.
The central device 6 sets the field of the used line to “wired” when performing communication with the traffic signal controller 1 by wired communication, and sets the field of the used line to “wireless” when performing wireless communication. Set to.

The “operation mode” is a field for instructing an operation method for the communication unit 2 for the traffic signal controller 1 capable of executing the power saving operation of the communication unit 2. In this field, either the normal mode or the power saving mode is set.
When the central device 6 causes the communication unit 2 of the traffic signal controller 1 to perform normal operation for supplying power as usual, the field of the operation mode is set to “normal mode” and the traffic signal controller 1 includes the communication unit. When the power saving operation of 2 is performed, the operation mode field is set to “power saving mode”.

The “duration” is a field for designating a time for which the traffic signal controller 1 continues the power saving operation. When the traffic signal controller 1 receives the signal control command Sd instructing the power saving mode, the traffic signal controller 1 transmits only the time value (2 hours in FIG. 3) indicated in the duration field from the reception time. Execute power-saving operation for.
In addition, the description format of the time with respect to the duration field may not be the time itself as shown in FIG. 3 but may be a format in which a time value at which the traffic signal controller 1 ends the power saving operation is written.

Although not shown in FIG. 3, the signal control command Sd generated by the central device 6 includes a field for designating permission / inhibition of terminal sensitivity control (for example, gap sensitivity or dilemma sensitivity) by the traffic signal controller 1. Also good.
The central control unit 61 of the central device 6 determines the data content described in each field shown in FIG. 3 for each traffic signal controller 1 in the jurisdiction area, generates the signal control command Sd, and responds to the generated command Sd. The traffic signal controller 1 is transmitted to the central communication unit 63.

[Contents of signal control execution information]
FIG. 4 is a table showing an example of the content of the signal control execution information Su generated by the traffic signal controller 1.
As shown in FIG. 4, the signal control execution information Su includes fields (storage areas) such as “execution offset”, “number of seconds in the step”, “sensing information”, and “terminal sensitive information”.
Of the above fields, “Execution offset” is a field for describing the second value of the offset executed by the traffic signal controller 1 in the previous cycle, and “Strand second” is the field for the traffic signal controller 1 in the previous cycle. This field describes the second value of each executed step.

The “sensor information” is a field for describing predetermined information acquired from the vehicle detectors 52 and 53 managed by the traffic signal controller 1, and is detected by the ultrasonic vehicle sensor 52 in the example of FIG. The number of vehicles made is noted.
“Terminal sensitivity information” is a field that indicates the seconds value of the changed floor when the traffic signal controller 1 performs predetermined terminal sensitivity control. In the example of FIG. 4, blue extension is performed for 5 seconds. It is written.

  The control unit 3 (specifically, the CPU 31) of the traffic signal controller 1 determines the data value described in each field shown in FIG. 4 for each cycle, generates the signal control execution information Su, and generates the generated information Su. Is transmitted to the communication unit 2 addressed to the central device 6.

[Operation sequence in power saving mode]
FIG. 5 is a sequence diagram of communication frames Sd and Su transmitted / received between the central device 6 and the traffic signal controller 1.
Hereinafter, the contents of the power saving mode for the communication unit 2 of the traffic signal controller 1 executed in cooperation with the central device 6 and the traffic signal controller 1 will be described with reference to FIG.

In FIG. 5, “C” is a cycle length designated by the central device 6 and C = 120 seconds.
In FIG. 5, “Sd” is a “signal control command” transmitted from the central device 6 toward the traffic signal controller 1, and “Su” is directed to the central device 6 by the traffic signal controller 1. "Signal control execution information" to be transmitted upstream. Further, “Sd1” is a signal control command Sd for instructing the start of the power saving mode, and “Sd2” is a signal received by the traffic signal controller 1 during the duration of the power saving mode after the command Sd1. It is assumed that the control command is Sd.

The central device 6 transmits a signal control command Sd1 to a predetermined traffic signal controller 1 belonging to the jurisdiction area of its own device, for example, during a time period when the power demand is large, such as during the daytime in summer. The traffic signal controller 1 is caused to start the power saving mode.
That is, the central device 6 transmits a signal control command Sd1 in which the “driving mode” is switched from the normal mode to the power saving mode to the traffic signal controller 1 that performs the power saving mode. Requests the communication unit 2 to perform power saving operation.

In the signal control command Sd1 instructing the power saving mode, in addition to setting the operation mode to the power saving mode as described above, the “duration” when performing the power saving operation of the communication unit 2 and the duration time Specific values of “reception period” and “transmission period” that are allowed to be transmitted to and received from the central apparatus 6 are described.
For example, in the signal control command Sd1 of FIG. 5, the duration is T0, the reception cycle is T1, and the transmission cycle is T2. These values are T0 = 2 hours, T1 according to the example of FIG. = 300 seconds and T2 = 300 seconds.

When the CPU 31 of the traffic signal controller 1 receives the command Sd1 instructing the power saving mode, the CPU 31 outputs a control signal Sa for starting sleep (see FIG. 1) to the communication control unit 22 almost simultaneously with the reception time t1 to perform communication. The unit 2 is put into a sleep state.
Further, the CPU 31 calculates the end time t2 of the sleep time Ts based on the cycles T1 and T2 described in the signal control command Sd1, and communicates the control signal Sb (see FIG. 1) for ending the sleep at the end time t2. It outputs to the control part 22, and returns the communication part 2 to an awake state.

Specifically, the CPU 31 subtracts the communication time Tc necessary for exchanging the signal control command Sd2 and the execution information Su with the central device 6 from the reception and transmission cycles T1 and T2 (= 300 seconds). The time (= T1-Tc) is set as the sleep time Ts.
Here, during the communication time Tc, the communication unit 2 returns from the sleep state to the awake state, and the preparation time Tr necessary for establishing a line with the central device 6 is actually transmitted and received after the establishment. And the actual working time Te.

For example, when the preparation time Tr is set to 20 seconds and the actual working time Te is set to 10 seconds, the time (270 seconds) obtained by subtracting 30 seconds from the grace time until the next transmission / reception (= 300 seconds) The sleep time Ts is reached.
As described above, the reason for including the preparation time Tr in the necessary communication time Tc is that the communication unit 2 is once in the sleep state, and only after a predetermined communication frame is transmitted and received to establish a line with the central device 6. This is because the transmission / reception unit 21 cannot transmit the execution information Su to the central device 6 and the transmission / reception unit 21 cannot receive the signal control command Sd from the central device 6.

When the communication unit 2 returns to the awake state at the end time t2 of the sleep time Ts, the transmission / reception unit 21 transmits the signal control execution information Su during the working time Te after the preset preparation time Tr has elapsed, The next signal control command Sd2 is received from the device 6.
Thereafter, the CPU 31 of the traffic signal controller 1 outputs a sleep start control signal Sa almost simultaneously with the reception time t3 of the next signal control command Sd2 to cause the communication unit 2 to sleep, and the next sleep time Ts (= 270 seconds). At the same time, a control signal Sb for ending sleep is output to awaken the communication unit 2.

The CPU 31 stores the reception time t1 of the signal control command Sd1 instructing the start of the power saving mode and the duration T0 (= 2 hours) described in the command Sd1 in the storage device.
Then, until the stored duration time elapses or until the duration time is changed in the next and subsequent commands Sd2, the CPU 31 starts sleep when triggered by reception of each signal control command Sd2. The control signal Sa is output, and the sleep end control signal Sb is output at the end time t2 of the sleep time Ts obtained from the cycles T1 and T2 designated by the central device 6.

As a result, the communication unit 2 of the traffic signal controller 1 repeats the sleep state and the awake state at predetermined time intervals during the duration specified by the central device 6.
On the other hand, when changing the duration T0 of the power saving mode, the central device 6 writes another time value in the “duration” field of the second and subsequent signal control commands Sd2, and changes the periods T1 and T2. In this case, another time value is written in the “reception cycle” and “transmission cycle” fields of the second and subsequent signal control commands Sd2.

When there is a change in the duration included in the signal control command Sd2, the CPU 31 of the traffic signal controller 1 updates the stored data of the time value and keeps the sleep state until the updated duration has elapsed. The power saving mode described above that causes the communication unit 2 to repeat the awake state is continued.
Further, when the reception cycle T1 or the transmission time T2 included in the signal control command Sd2 is changed, the CPU 31 newly calculates and updates the sleep time Ts based on the changed cycles T1 and T2, At the end of the sleep time Ts, the sleep end control signal Sb is output.

The central device 6 transmits a signal control command Sd2 for switching the field of the operation mode to the normal mode when the duration T0 notified to the traffic signal controller 1 has elapsed, and the CPU 31 of the traffic signal controller 1 After receiving the command Sd2, the sleep start control signal Sa is not output to the communication control unit 22.
In the present embodiment, since the communication unit 2 of the traffic signal controller 1 supports both wired and wireless, the CPU 31 determines that the “use line” of the signal control command Sd is set to wireless. The sleep mode is performed for the wireless function of the transmission / reception unit 21.

[Another operation sequence in power saving mode]
FIG. 6 is another sequence diagram of the communication frames Sd and Su transmitted / received between the central device 6 and the traffic signal controller 1.
The sequence in FIG. 6 is different from that in FIG. 5 in that the reception cycle T1 and the transmission cycle T2 are set to different time values in the signal control command Sd1 instructing the start of the power saving mode. In the example, it is assumed that the reception cycle T1 = 300 seconds and the transmission cycle T2 = 500 seconds.

In this case, as in the case of FIG. 5, the CPU 31 of the traffic signal controller 1 receives the signal control command Sd <b> 1 instructing the power saving mode, and sends the sleep start control signal Sa (see FIG. 1) to the communication unit 2. It outputs to the communication control part 22, and makes the communication part 2 a sleep state.
Further, the CPU 31 calculates the end time t2 of the sleep time Ts1 based on the reception cycle T1 described in the signal control command Sd1, and performs communication control of the control signal Sb (see FIG. 1) for end of sleep at the end time t2. The data is output to the unit 22, and the communication unit 2 is returned to the awake state.

Specifically, as shown in FIG. 6, the CPU 31 receives the signal control command Sd2 from the central device 6 from the reception cycle T1 (= 300 seconds), which is a delay time from the reception time t1 to the next reception. The time (= T1−Tc1) obtained by subtracting the communication time Tc1 necessary for the above is set as the sleep time Ts1.
Here, also in the communication time Tc1, the preparation time Tr1 (= 20 seconds) required until the communication unit 2 returns from the sleep state to the awake state and establishes a line with the central device 6, and the actual time after the establishment. Includes a working time Te1 (= 10 seconds) for receiving a communication frame.

When the communication unit 2 returns to the awake state at the end time t2 of the sleep time Ts1, the transmission / reception unit 21 performs the next signal control from the central device 6 during the working time Te1 after the preset preparation time Tr1 has elapsed. Command Sd2 is received.
Note that it is only necessary to receive the signal control command Sd2 during the actual working time Te1, so it is not necessary to awaken both functions of the transmission / reception unit 21, and only the reception function may be awakened while the transmission function is in the sleep state. .

  As described above, in the example of FIG. 6, the reception cycle T1 and the transmission cycle T2 are different. Therefore, the CPU 31 calculates the end time t4 of the next sleep time Ts2 based not only on the shorter reception cycle T1 (= 300 seconds) but also on the longer transmission cycle T2 (= 500 seconds). Then, at the end time t4, the control signal Sb for ending the sleep is output, and the communication unit 2 is returned to the awake state.

Specifically, as shown in FIG. 6, it is necessary to further transmit the execution information Su to the central apparatus 6 from the time obtained by subtracting the reception period T1 (= 300 seconds) from the transmission period T2 (= 500 seconds). A time obtained by subtracting the communication time Tc2 (= T2-T1-Tc2) is set as the next sleep time Ts2.
Here, also during the communication time Tc2, the preparation time Tr2 required until the communication unit 2 returns from the sleep state to the awake state and establishes a line with the central apparatus 6, and the communication frame is actually received after the establishment. The actual working time Te2 for performing is included.

When the communication unit 2 returns to the awake state at the end time t4 of the sleep time Ts2, the transmission / reception unit 21 transmits the signal control execution information Su to the central device during the actual operation time Te2 after the preset preparation time Tr2 has elapsed. 6 to send.
It should be noted that since it is sufficient that the execution information Su can be transmitted during the actual working time Te2, it is not necessary to awaken both functions of the transmission / reception unit 21, and only the transmission function may be awakened while the reception function is set to sleep.

[Effect of traffic signal controller]
As described above, according to the traffic signal controller 1 of the present embodiment, the control unit 3 (CPU 31) needs communication for exchanging the signal control command Sd and the signal control execution information Su with the central device 6. Other than the time Tc, the communication unit 2 is set in the sleep state to suppress power feeding. Therefore, the central device 6 is compared with the conventional device that always operates the communication unit 2 for transmission of the floor information K1 to K10 (see FIG. 7). The power consumption required for communication with can be reduced.
For this reason, the several traffic signal controller 1 which comprises a traffic signal control system can aim at the power-saving of the whole system by reducing the power consumption required for communication.

Further, according to the traffic signal controller 1 of the present embodiment, the control unit 3 (CPU 31) includes fields of “reception period” and “transmission period” included in the signal control command Sd received from the central device 6 (FIG. 3). Since the time zone (sleep time Ts) in which the communication unit 2 is in the sleep state is determined according to the value of the reference), the setting of the sleep time Ts for each traffic signal controller 1 belonging to the jurisdiction area is concentrated from the central device. Can be done by control.
For this reason, compared with the case where the sleep time Ts is individually set for each traffic signal controller 1 in the jurisdiction area, the power saving of the entire system can be easily achieved.

  Further, according to the traffic signal controller 1 of the present embodiment, the control unit 3 (CPU 31) determines the sleep time Ts and the communication time according to the designation content of the “operation mode” (see FIG. 3) included in the signal control command Sd. Since the power saving operation is repeated according to the value of the “duration” (see FIG. 3) included in the signal control command Sd, the power saving operation of the traffic signal controller 1 is changed to the power saving operation that repeats Tc. The transition and the duration of power saving operation can also be set by centralized control from the central device.

[First Modification]
In the above-described embodiment, the communication unit 2 is set to sleep except for the communication time Tc necessary for receiving the signal control command Sd and transmitting the signal control execution information Su. When the information is generated, the communication unit 2 may be awakened exceptionally and the emergency information may be transmitted to the central device 6.
Examples of the emergency information include the “blue-blue abnormality”, “timer abnormality”, and “manual stepping” that can be detected by the CPU 31. This is because these important emergency information should be preferentially notified to the central device 6 even if the reduction of power consumption in the communication unit 2 is given up.

In this case, when the CPU 31 determines any of the above abnormalities during the sleep time Ts determined according to the cycles T1 and T2 designated from the central device 6, the CPU 31 immediately outputs the control signal Sb for ending the sleep to the communication control unit 22. The communication unit 2 is awakened and the emergency information is transmitted upstream to the communication unit 2.
In this way, even in the case of the traffic signal controller 1 according to the present embodiment that saves power by putting the communication unit 2 in the sleep state, the normal traffic signal controller 1 that does not perform power saving. Similarly, the central device 6 can be properly notified of the occurrence of important emergency information.

[Second Modification]
In the above-described embodiment, the communication unit 2 is switched to the sleep state or the awake state by the control signals Sa and Sb output from the CPU 31 that performs traffic signal control, but the communication control unit 22 itself may perform the switching. .
That is, the communication control unit 22 performs the process of entering the sleep state upon reception of the signal control command Sd1 and returning to the awake state at the end of the sleep time Ts obtained from the reception cycle T1 or the transmission cycle T2, based on the timer of its own device. You may make it carry out autonomously.

Moreover, in the above-mentioned embodiment, although the case where the power supply with respect to the communication part 2 was suppressed rather than usual by putting the communication part 2 into a sleep state was illustrated, the power saving which the traffic signal controller 1 performs with respect to the communication part 2 The mode may stop the power supply from the power supply unit 4 to the communication unit 2.
In this case, since the power supply is stopped, there is an advantage that the power saving effect is improved, but the shock to the circuit element when the power supply to the communication control unit 22 is resumed is large. For this reason, it is preferable to perform the power saving operation using the communication control unit 22 corresponding to the sleep as in the above-described embodiment.

[Third Modification]
In the above-described embodiment, the control unit 3 (CPU 31) of the traffic signal controller 1 puts the communication control unit 22 in the sleep state except for the communication time Tc necessary for exchanging the signal control command Sd and the signal control execution information Su. By doing so, all the floor information K1 to K10 (see FIG. 7) transmitted in the conventional machine is not transmitted, but some of the floor information (for example, only the floor information K1 of step 1) ), The communication unit 2 may be returned to the awake state and transmitted to the central device 6.

In this case, the time zone for suppressing or stopping power supply to the communication unit 2 is limited to a predetermined time that is less than or equal to the cycle length. For that predetermined time, the power supply to the communication unit 2 is suppressed or stopped. By doing so, a power saving effect can be obtained.
Therefore, the power consumption required for communication with the central device 6 can be reduced as compared with the conventional machine in which the communication unit 2 is required to always operate in order to transmit all the floor information K1 to K10.

[Other variations]
The embodiment disclosed this time (including the above-described modifications) is illustrative in all respects and not restrictive. The scope of the right of the present invention is not the embodiment described above, but includes all modifications within the scope equivalent to the scope of the claims.
For example, in the above-described embodiment, the signal control command Sd is adopted as a command for notifying the traffic signal controller 1 of the start or time of the power saving mode. However, the signal control command Sd is saved by a communication frame separate from the signal control command Sd. The start of the power mode and the time may be notified.

Further, in the above-described embodiment, the central device 6 transmits the communication frame Sd only to some traffic signal controllers 1 in the jurisdiction area when the power saving mode is carried out in its own jurisdiction area. The power saving mode may be performed.
Further, in the above-described embodiment, when the traffic signal controller 1 is provided with an auxiliary power source (solar cell or the like) and a battery and the amount of power from the commercial power source 7 is insufficient, the power from the auxiliary power source or the battery is supplied to each device. The power supply may be supplemented.

DESCRIPTION OF SYMBOLS 1 Traffic signal controller 2 Communication part 3 Control part 4 Power supply part 6 Central apparatus 21 Transmission / reception part 22 Communication control part 31 CPU
Sd signal control command Su signal control execution information
Ts Sleep time Tc Communication time

Claims (10)

A traffic signal controller for controlling the timing of switching the color of a signal lamp,
A communication unit communicating with the central device;
Other than the communication time required for exchanging predetermined information with the central device, a control unit for suppressing or stopping power feeding to the communication unit,
A traffic signal controller characterized by comprising:   The traffic signal controller according to claim 1, wherein the communication time includes a preparation time required for establishing a line with the central device and an actual operation time after the establishment.   The traffic signal controller according to claim 1 or 2, wherein the predetermined information includes a signal control command that the central device transmits to the communication unit in order to notify the traffic signal controller of a signal control parameter.   4. The predetermined information includes signal control execution information that the communication unit transmits to the central device in order to notify the central device of the control content actually performed by the traffic signal controller. The traffic signal controller according to any one of the above.   5. The emergency information transmitted from the communication unit to the central device in order for the traffic signal controller to notify the central device of an emergency situation is included in the predetermined information. The traffic signal controller described. The predetermined command that the central device transmits to the communication unit includes an area that specifies a reception cycle when the communication unit receives the predetermined information;
The traffic signal controller according to any one of claims 1 to 5, wherein the control unit determines a time zone in which power supply to the communication unit is suppressed or stopped according to the value of the reception cycle included in the command. The predetermined command that the central device transmits to the communication unit includes an area that specifies a transmission cycle when the communication unit transmits the predetermined information;
The traffic signal controller according to any one of claims 1 to 6, wherein the control unit determines a time zone in which power supply to the communication unit is suppressed or stopped according to the value of the transmission cycle included in the command. The predetermined command that the central device transmits to the communication unit includes a region that specifies an operation mode for the communication unit,
The said control part performs the power saving operation which repeats the time slot | zone which suppresses or stops the electric power feeding with respect to the said communication part, and the said communication time, when the said operation mode designated by the said instruction | command is a power saving mode. The traffic signal controller according to any one of? 7. The command includes an area for specifying the duration of the power saving operation,
The traffic signal controller according to claim 8, wherein the control unit continues the power saving operation in accordance with the duration value included in the command. A traffic signal controller for controlling the timing of switching the color of a signal lamp,
A communication unit communicating with the central device;
The communication unit stops transmitting all or part of the floor information indicating the transition of the floor in one cycle to the central device, and power supply to the communication unit is suppressed during the period when the transmission is stopped or A control unit to stop;
A traffic signal controller characterized by comprising:

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