JP2024057428A - Automatic power switching type traffic signal controller - Google Patents

Abstract

[Problem] To provide an automatic power supply switching type traffic signal controller that switches between a commercial power supply and an external power supply with a simple structure. [Solution] A traffic signal controller 1 includes a control unit 2, a communication unit 3 that is connected to the control unit 2 and transmits and receives various data, a converter unit 4 that supplies DC power to the control unit 2 and the communication unit 3, and a power supply switching unit 7 that connects to the converter unit 4 and a plurality of power supplies E. The power supply switching unit 7 is composed of a switch unit 7b having a movable contact 7a that can be switched between a first connection state of the converter unit 4 and a commercial power supply E1 or a second connection state of the converter unit 4 and an external power supply E2, and a movable contact control unit 7c that is connected to the commercial power supply E1. Depending on whether or not electricity is applied to the movable contact control unit 7c, the first and second connection states are switched, and only one of the commercial power supply E1 and the external power supply E2 supplies power to the internal devices of the traffic signal controller 1 via the power supply switching unit 7. [Selected Figure] Figure 1

Description

The present invention relates to a traffic signal controller that is connected to traffic signal lights and vehicle detectors installed at intersections, for example, and performs various controls on the traffic signal lights and vehicle detectors.

Patent document 1 discloses an outdoor traffic control terminal device that is powered by a commercial power source and an auxiliary power source such as a battery, detects a commercial power outage, and switches over to operation from the auxiliary power source.

This outdoor traffic control terminal device is powered by an auxiliary power source and has a comparison section consisting of a comparator and a switching section that switches between commercial power and the auxiliary power source based on a signal input from this comparison section.

When the comparison unit determines that the input voltage from the commercial power source drops and that the input voltage from the auxiliary power source is clearly higher, it outputs a signal to the switching unit, which then switches from the commercial power source to the auxiliary power source.

In addition, if the comparison unit determines that the input voltages from the commercial power supply and the auxiliary power supply are equal, it can turn off the signal output to the switching unit, causing the switching unit to switch from the auxiliary power supply to the commercial power supply and return to the original connection state.

Japanese Patent Application Laid-Open No. 6-22474

However, in the outdoor traffic control terminal device of Patent Document 1, in order to switch between commercial power and auxiliary power, it is necessary to measure the input voltage from both the commercial power source and the auxiliary power source. Therefore, wiring is required to measure the voltage from the commercial power source and the external power source, which is time-consuming.

The object of the present invention is to solve the above-mentioned problems and provide an automatic power supply switching type traffic signal controller that switches between commercial power supply and external power supply with a simple configuration.

The automatic power supply switching type traffic signal controller according to the present invention, which is intended to achieve the above object, is an automatic power supply switching type traffic signal controller that includes a control unit that is connected to a signal lamp and controls the lighting of the signal lamp, a converter unit that supplies power to the control unit, and a power supply switching unit that is connected to the converter unit and the first and second AC power sources via power lines. The power supply switching unit includes a switch unit having a movable contact that switches between a first connection state that connects the converter unit and the first AC power source, or a second connection state that connects the converter unit and the second AC power source, and a movable contact control unit that is disposed near the movable contact and attracts the movable contact when energized and releases the attraction of the movable contact when de-energized, and is characterized in that the first and second connection states are switched depending on whether or not current is applied to the movable contact control unit.

The automatic power supply switching type traffic signal controller of the present invention can automatically switch between commercial power and external power with a simple configuration without using complex circuits.

FIG. 2 is a block circuit diagram of an automatic power supply switching type traffic signal controller. FIG. 2 is a block circuit diagram of an automatic power supply switching type traffic signal controller when the power supply is switched. FIG. 1 is a block circuit diagram of a conventional traffic signal controller.

The present invention will now be described in detail with reference to the illustrated embodiments.
FIG. 1 is a block circuit diagram of an automatic power switching type traffic signal controller 1 installed near an intersection. The housing of the traffic signal controller 1 is provided with a sealed door for maintenance purposes.

The traffic signal controller 1 is composed of a control unit 2 that controls the lighting of the traffic signal lamps L via a lamp output unit and inputs vehicle detection signals from vehicle detectors D, a communication unit 3 that is connected to the control unit 2 and transmits and receives various data to the center device C via a wired or wireless network N, a converter unit 4 that is connected to the control unit 2 and communication unit 3 and supplies DC power to the control unit 2 and communication unit 3, a lamp output unit 5 that turns on the traffic signal lamps L in response to an output command from the control unit 2, a power source switching unit 7 that is connected to the converter unit 4 and multiple power sources E, such as a commercial power source via a generator and a breaker 6, via a power line, and first and second light emitting units 8 and 9 that are connected to the power source switching unit 7 and consist of light emitting members such as LEDs.

Each of these devices is housed within the housing of the traffic signal controller 1, and the center device C, which is connected to the traffic signal controller 1 via the network N, performs centralized control and monitoring of the multiple traffic signal controllers 1 and vehicle detectors D under its management.

The control unit 2 outputs output commands to the light output unit 5, which turns on the red, yellow, and blue lights of the vehicle traffic signal lights installed at the intersection, and the red and blue lights of the pedestrian lights, according to the stored traffic signal light L indication table.

The control unit 2 is also connected to the vehicle detector D and the communication unit 3 via signal lines SG, and various data is sent and received via these signal lines SG. The vehicle detector D is connected to an AC 100V power line from the power supply switching unit 7.

The vehicle detector D does not necessarily need to be installed at the intersection, and if the traffic signal controller 1 is operated independently at the intersection, there is no need to provide a communication unit 3 that communicates with the center device C.

The converter unit 4 is an AC/DC converter that outputs, for example, DC 5V in response to an input of, for example, AC 100V. These DC 5V power lines are connected to the control unit 2 and the communication unit 3.

A power supply switching unit 7 is disposed between the converter unit 4 and the commercial power supply E1, which is the first AC power supply, and the external power supply E2, which is the second AC power supply. This power supply switching unit 7 is composed of a switch unit 7b having a movable contact 7a that can be switched to either a first connection state of the converter unit 4 and the commercial power supply E1, or a second connection state of the converter unit 4 and the external power supply E2, and a movable contact control unit 7c that is disposed near the switch unit 7b and is connected to the commercial power supply E1.

In addition, a commercial power source E1 of a predetermined voltage, for example, AC 100V, is connected to the switch unit 7b and movable contact control unit 7c of the power source switching unit 7 via a breaker 6.

This breaker 6 automatically cuts off the power supply from the commercial power source E1 if the circuit of the traffic signal controller 1 shorts out and causes an overcurrent or a power leak.

The external power source E2 is equipped with an inverter and outputs 100V AC like the commercial power source E1. It can be a diesel generator that generates electricity by burning fuel such as diesel, a generator that generates electricity using natural energy such as solar or wind power, or a storage battery that stores electricity in advance.

An electromagnet such as a coil magnet is used in the movable contact control unit 7c, and when power is supplied from the commercial power source E1, that is, when the movable contact control unit 7c is energized, the movable contact 7a made of iron or the like is attracted by magnetic force, resulting in a first connection state that connects the converter unit 4 and the commercial power source E1.

Conversely, when the power supply from the commercial power source E1 is cut off, that is, when the movable contact control unit 7c is not energized, the movable contact control unit 7c releases the magnetic attraction of the movable contact 7a by gravity and spring action, and switches to a second connection state in which the converter unit 4 and the external power source E2 are connected, as shown in FIG. 2.

In other words, the first and second connection states are switched depending on whether the movable contact control unit 7c is energized or de-energized. Therefore, only one of the commercial power source E1 and the external power source E2 can supply power to the internal devices of the traffic signal controller 1 via the power source switching unit 7.

Furthermore, a first light-emitting unit 8 and a second light-emitting unit 9 that emit light when power is being supplied are connected to the commercial power source E1 and the external power source E2, respectively, and these first and second light-emitting units 8 and 9 are, for example, LED elements.

The first light-emitting unit 8 and the movable contact control unit 7c are connected in parallel to the commercial power source E1, and emit light in the first connection state. The second light-emitting unit 9 branches off from the power line between the switch unit 7b and the external power source E2, and emits light in the second connection state. The first light-emitting unit 8 may also be provided by branching off from the power line between the switch unit 7b and the external power source E2.

The first and second light-emitting units 8 and 9 may be light-emitting elements that emit light of different colors, and are visible when the sealed door on the front of the housing of the traffic signal controller 1 is open. Alternatively, a glass window or the like may be provided in the housing, and the light-emitting units may be visible when the sealed door is closed.

The lamp output unit 5 receives an AC 100V power line from the power supply switching unit 7, and based on an output command from the control unit 2 according to the current display table, it connects the received power line to output lines that turn on the red, yellow, and blue lights of the traffic signal lamp L.

Under normal circumstances, the traffic signal controller 1 is operated in the state shown in FIG. 1, and power is constantly supplied to the traffic signal controller 1 from the commercial power source E1. However, in the event of a power outage due to a disaster or other reason that cuts off the power supply from the commercial power source E1, the switch unit 7b automatically switches from the connection state shown in FIG. 1 to the connection state shown in FIG. 2.

As mentioned above, under normal circumstances, power is supplied from the commercial power source E1 to the movable contact control unit 7c, which attracts the movable contact 7a by magnetic force, resulting in the first connection state.

When a power outage occurs, the power supply to the movable contact control unit 7c is cut off, and the movable contact control unit 7c is released from the magnetic attraction of the movable contact 7a and enters the second connection state. By switching to this second connection state, power can be continuously supplied to the internal devices of the traffic signal control device 1 even during a power outage.

In the block circuit diagram shown in FIG. 1, the external power source E2 is connected in advance, but after a power outage occurs in the commercial power source E1, an external power source E2 such as a diesel generator or a storage battery prepared by an operator or the like may be connected to start supplying power to the traffic signal controller 1.

In this way, while power is being supplied to the traffic signal controller 1 from the external power source E2 that was connected after the power outage occurred, if the power outage at the commercial power source E1 is resolved and the power supply is restored, the movable contact control unit 7c, which is automatically energized, will attract the movable contact 7a, and the connection state will be switched from the second connection state to the first connection state.

Then, by checking the light emitted by the first and second light-emitting units 8 and 9, workers can determine whether the commercial power source E1 has been restored, and when the first light-emitting unit 8 is emitting light, they can remove the external power source E2 that is no longer needed.

In another embodiment, an external power source E2 such as a solar power generator can be used as the first AC power source on the side that has the movable contact control unit 7c, and a commercial power source E1 can be used as the second AC power source on the side that does not have the movable contact control unit 7c.

By reversing the arrangement of the commercial power source E1 and the external power source E2 in FIG. 1, for example, during the day, the system will be in a first connection state in which power is supplied from the external power source E2, which is a solar power generator that generates power from sunlight, a natural energy source, and at night, when no power is generated, the system will automatically switch to a second connection state in which power is supplied from the commercial power source E1. In other words, the system will automatically switch from the second connection state to the first connection state in the morning, and from the first connection state to the second connection state in the evening.

Figure 3 is a block circuit diagram of a conventional traffic signal controller 1' installed near an intersection. In the conventional traffic signal controller 1', power is supplied only from the commercial power source E1, and the control unit 2 to the breaker 6 are stored within the housing. Each of these devices is the same as the devices stored within the housing of the automatic power supply switching type traffic signal controller 1 shown in Figures 1 and 2.

Then, by modifying this traffic signal controller 1' by adding a power supply switching unit 7 and first and second light emitting units 8 and 9 that enable connection to an external power supply E2, and by arranging the external power supply E2, it becomes possible to switch the connection state between the commercial power supply E1 and the external power supply E2 as described above. Note that when this modification is made, there is no need to change the software of the control unit 2, etc.

In this way, the automatic power supply switching type traffic signal controller of the present invention can automatically switch between the commercial power supply E1 and the external power supply E2 with a simple structure, without using complex circuits as in conventional switching structures, and only one of the commercial power supply E1 and the external power supply E2 can supply power to various devices via the power supply switching unit 7.

REFERENCE SIGNS LIST 1 Automatic power supply switching type traffic signal controller 2 Control unit 4 Converter unit 7 Power supply switching unit 7a Movable contact 7b Switch unit 7c Movable contact control unit 8 First light emitting unit 9 Second light emitting unit E1 Commercial power supply E2 External power supply

Claims (7)

An automatic power supply switching type traffic signal controller including a control unit that is connected to a signal lamp and controls the lighting of the signal lamp, a converter unit that supplies power to the control unit, and a power supply switching unit that is connected to the converter unit and first and second AC power supplies via power lines,
the power supply switching unit includes a switch unit having a movable contact configured to switch between a first connection state in which the converter unit and the first AC power supply are connected and a second connection state in which the converter unit and the second AC power supply are connected;
a movable contact control unit that is disposed in the vicinity of the movable contact and that attracts the movable contact when energized and releases the attraction of the movable contact when deenergized;
An automatic power supply switching type traffic signal controller, characterized in that the first and second connection states are switched depending on whether electricity is supplied or not to the movable contact control unit. The automatic power supply switching type traffic signal controller according to claim 1, characterized in that when the movable contact control unit is energized, the first connection state is established, and when the movable contact control unit is not energized, the second connection state is established. The automatic power supply switching type traffic signal controller according to claim 1 or 2, characterized in that it comprises a first light-emitting unit disposed between the power supply switching unit and the first AC power supply, which emits light when in a first connection state, and a second light-emitting unit disposed between the power supply switching unit and the second AC power supply, which emits light when in a second connection state. The automatic power supply switching type traffic signal controller according to any one of claims 1 to 3, characterized in that the first AC power supply is a commercial power supply, and the second AC power supply is a generator or a storage battery. The automatic power supply switching type traffic signal controller according to any one of claims 1 to 3, characterized in that the first AC power supply is a generator and the second AC power supply is a commercial power supply. The automatic power supply switching type traffic signal controller according to claim 4, characterized in that the generator generates electricity by burning fuel. The automatic power supply switching type traffic signal controller according to claim 5, characterized in that the generator generates electricity using natural energy.

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