GB2549112A

GB2549112A - Display system

Info

Publication number: GB2549112A
Application number: GB1605790.3A
Authority: GB
Inventors: James Wood Timothy
Original assignee: M2m Tech Ltd
Current assignee: M2m Tech Ltd
Priority date: 2016-04-05
Filing date: 2016-04-05
Publication date: 2017-10-11
Anticipated expiration: 2036-04-05
Also published as: GB2549112B

Abstract

A display system with an electronic display device (34, 18), and a source (28) of electricity for the electronic display device. The system has a circuit (32) to provide electricity to the electronic display device (34, 18), the circuit (32) being actuated in response to input (20) from a user, such as a button press, and subsequently being arranged to terminate the provision of electricity to the electronic display device after a delay interval, so that the electronic display device is turned off and uses no electricity after a set period of time passes. The circuit (32) may include an optocoupler that operates in response to a control signal from the electronic display device (34). The system may include a rechargeable battery (28) as the source of electricity, and an environmental energy source (24) such as a solar panel to provide electricity to the rechargeable battery. The display system may be part of a bus stop.

Description

Display System

The present invention relates to a system for providing an electronic display, particularly but not exclusively in a context in which mains electricity is not available. A number of systems have been suggested to enable a display to be provided at such a location. It is conventional to provide printed information about bus schedules in a display panel at a bus stop, but at night such a printed display can be read only with an external source of illumination, which may for example be provided by adjacent streetlights. US 2006/0120068 describes a bus stop that includes a solar-powered assembly and which includes LED (light emitting diodes) lighting which a customer can use for illuminating a bus schedule, under the control of a button or switch. The schedule information is printed onto a translucent sheet. This may be satisfactory as a way of providing schedule information, if the schedule remains constant for a prolonged period, but is not adequate to provide real-time information. It has also been proposed to install electronic displays at such locations, as such displays enable the information to be altered to ensure up-to-date information, but the power consumption of such displays is such that it is difficult to ensure continuous operation without a connection to mains electricity; for example GB 2 457 506 describes a bus shelter with an electronic display, in which power is provided partly by a solar panel and partly by mains electricity.

According to the present invention there is provided a display system comprising an electronic display device, and a source of electricity for the electronic display device, wherein the system also comprises a circuit to provide electricity to the electronic display device, the circuit being actuated in response to input from a user, and subsequently being arranged to terminate the provision of electricity to the electronic display device after a delay interval, so that the electronic display device is off and uses no electricity.

In a preferred embodiment the circuit includes an actuating button whereby a user can create an electrical connection, to initiate operation of the electronic display device, and the circuit also including a relay component providing a connection in parallel to that provided by the actuating button, wherein the electronic display device is arranged to provide a control signal to the relay component to actuate the parallel connection, and is subsequently arranged to terminate the control signal to deactivate the parallel connection, so the circuit provides no electricity to the electronic display device.

The relay component is a component which provides an electrical connection in response to a control signal. It may for example be an electromechanical relay, or a transistor. In one preferred embodiment the relay component is an optocoupler, as this can be a low-power device.

In one embodiment the system includes a rechargeable battery as the source of electricity for the electronic display device, and an environmental energy source to provide electricity to the rechargeable battery.

The environmental energy source refers to a source of electricity provided from the environment. It may for example be a wind rotor connected to a generator, or in some situations it may be a small scale hydroelectric generator, but is more commonly a solar panel, more specifically a photovoltaic solar panel. Another option is to combine such sources of electricity, for example a wind rotor and also a solar panel. A common feature of such environmental energy sources is that they do not provide a constant electrical output over a prolonged period. For example a solar panel will provide more electrical power during the middle of the day than during morning or evening, and will not provide electrical power overnight. The electric power is therefore stored in a rechargeable battery, so electric power is available to operate the electronic display device whenever needed.

The electronic display device may for example be a microcomputer connected to a display module. The display module may be integral with the microcomputer, or may be a separate component.

The delay interval, after which the electronic display device is off and uses no electricity, should be long enough to enable the user to view and comprehend what is displayed by the electronic display device, but to minimise energy consumption the delay interval should be no longer than that. Typically what is displayed is information such as bus schedule or train schedule information, or live information about arrival times. By way of example the delay interval may be less than 5 minutes, more preferably less than 2 minutes, for example 60 seconds; but is preferably at least 10 seconds. If the electronic display device is a touch-screen device, the delay interval may restart each time the user touches the screen. A benefit of the present invention is that a user can actuate the electronic display device whenever this is needed; but that after the display device has provided the information required by the user, it is disconnected and draws no current. This is particularly convenient in applications such as a display in a bus stop, because typically there are no bus services and no users during much of the night, so throughout that period the electronic display device of the present invention draws no current. In contrast, some electronic display systems go into a standby mode when not being used; although the standby mode draws little current, the system may be in this mode for many hours, so the reduction in consumption of electricity arising from use of the present invention can be significant.

The reduction in electrical power achieved by the present invention may have a number of further benefits. It may increase the life of the product due to reduced wear, and it may reduce the size, weight and cost of ancillary components such as the rechargeable batteries and the environmental energy source, and consequently may reduce the size and strength required for the supporting structures, while improving the aesthetics of the resulting structure.

Hence, in another aspect, the invention provides a support structure incorporating a system as described above, wherein an environmental energy source is mounted on top of the support structure. Where the environmental energy source includes a solar panel, the solar panel may be mounted in such a way that its inclination from the horizontal can be adjusted at different times of year, for example being set at 45° during the summer but the angle of inclination being increased to for example 73° during the winter. This may enable the energy recovered by the solar panel to be increased; this is a particular concern during winter, day lengths are short and night lengths are long.

Such a support structure may be a bus stop structure, or an information kiosk, for example.

The invention will now be further and more particularly described, by way of example only, and with reference to the accompanying drawings in which:

Figure 1 shows a perspective view of a bus stop structure incorporating a system of the invention;

Figure 2 shows a schematic circuit diagram of the system of the invention;

Figure 3 shows part of the circuit diagram of figure 2 in greater detail; and Figure 4 shows internal details of part of the circuit diagram of figure 3.

Referring now to figure 1, a bus stop structure 10 consists of an extruded aluminium post 12 arranged upright in the ground. Near the top of the post 12 is a projecting placard 14 indicating that this is a bus stop; the placard 14 may also provide information about the numbers of the bus services that serve that bus stop. These features are conventional. At a convenient height on the post 12 is mounted an electronic display module 16 with a display screen 18 and a pushbutton 20 so a user can activate the display screen 18. On top of the post 12 is mounted a box 22 from which projects a photovoltaic solar panel 24. The mounting of the box 22 and the photovoltaic solar panel 24 are such that the solar panel 24 can be arranged to face south, and is inclined from the vertical.

Referring now to figure 2, the solar panel 24 is connected by a short length of high current conductor 25 to a charge controller 26, and the output current from the charge controller 26 is provided to a rechargeable battery 28, both the charge controller 26 and the rechargeable battery 28 being enclosed within the box 22 (represented by a broken line). The rechargeable battery 28 may for example provide a 12 V output voltage. A comparatively low current cable 30, for example a 1A cable, extends down within the extruded aluminium post 12 and is connected to the electronic display module 16 (represented by a broken line). Within the display module 16 the cable 30 is connected through a switching module 32 to an electronic controller 34, which provides signals to the display screen 18. The switching module 32 includes the pushbutton 20. The electronic controller 34 may be a microcomputer, and may include wireless data transmission and reception circuits.

If a user pushes the pushbutton 20 for at least a second, this initiates operation of the electronic controller 34 and so operation of the display screen 18. At the same time, the electronic controller 34 is arranged to provide a control signal through a connection 36 back to the switching module 32, which causes the switching module 32 to maintain a supply of electricity to the electronic controller 34. After a period of time, which may be determined by software within the electronic controller 34, the electronic controller 34 ceases to provide the control signal, and consequently the switching module 32 switches off the supply of electricity to the electronic control 34. No current therefore flows to the electronic display module 16 until a user again operates the pushbutton 20. It will thus be appreciated that in this respect the switching module 32 acts as a relay component. This period of time may be referred to as the delay interval, and may for example be pre-set at 30 seconds or 60 seconds.

Referring now to figure 3, this shows in more detail the circuitry within the switching module 32. The pushbutton 20 closes a switch 40 to connect the cable 30 (i.e. + 12 V dc) directly to the electronic controller 34; but when the user removes his finger from the pushbutton 20, the switch 40 opens. The switching module 32 also includes an optocoupler 42 which has four terminals: terminals 1 and 2 are connected to the cable 30 on either side of the switch 40; terminal 3 is connected to the connection 36 for the control signal, and terminal 4 is connected to the earth or negative line.

Referring now to figure 4, this shows internal circuit features within the optocoupler 42. The terminals 3 and 4 are connected to an input circuit 43 that includes two light emitting diodes 44 in parallel. The terminals 1 and 2 are connected to an output circuit 45 that includes a photodetector 46, and which provides a driving signal to the base of a power transistor 47. Hence as long as the control signal (+ 5 V) is provided by the electronic controller 34 via the connection 36 to the terminal 3, light is emitted by the light emitting diodes 44. Consequently light falls on the photodetector 46, so the output circuit 45 provides the drive signal to the base of the power transistor 47, so current can flow through the optocoupler 42 to provide electricity to the electronic controller 34. When the electronic controller 34 ceases to provide the control signal to the terminal 3, the light emitting diodes 44 cease to emit light, so there is no longer a drive signal provided to the base of the power transistor 47, and so no current can flow through the optocoupler 42 to the electronic controller 34. The electronic controller 34 is consequently off, and draws no current.

It will be appreciated that the internal circuit features shown in figure 4 are somewhat schematic. In practice the components may differ from those shown. For example on the input side, in a simpler arrangement the terminals 3 and 4 may be connected directly to an LED 44 without any additional circuit components; and on the output side, the power transistor 47 may be a phototransistor, the light from the LED being incident directly on the base of the phototransistor and causing it to conduct.

Thus in use, a potential bus passenger pushes the pushbutton 20, so initiating operation of the electronic controller 34 and so of the display screen 18. The electronic controller 34, which as mentioned above may be a microcomputer, may be arranged to communicate wirelessly with an external data source or base station, for example to provide up-to-date information on the location of buses, and the time when buses can be expected to arrive at the bus stop. The required information is displayed on the display screen 18. Alternatively the electronic controller 34 may display schedule information from its own internal memory, rather than relying on an external source of data. In any event the information is displayed on the display screen 18, until the software controlling the electronic controller 34 reaches the stage at which the control signal is no longer given through the connection 36, at which stage the electronic controller 34 and the display screen 18 are switched off, because no current is supplied to them. There is thus a delay interval before the display screen 18 is switched off, during which the bus passenger can ascertain the required information.

Although being described specifically in relation to a bus stop, and bus schedule information, it will be appreciated that the invention would be equally applicable in a range of other contexts. For example the display screen 18 may instead be utilised at a railway station, to provide passengers with information about train schedules, or in other situations to provide other information to people, for example tourist information.

As indicated above, where a solar panel 24 is used to obtain energy, it is advantageous if the solar panel faces south (in the northern hemisphere), and is inclined from the horizontal. In some time an optimum angle is about 45° from the horizontal, whereas in winter time an optimum angle is about 73° from the horizontal (17° from the vertical). The mounting of the solar panel 24 on the box 22 may therefore be arranged such that the angle can be altered, for example every two or three months, through the year. Alternatively, the angle may be set at an angle suitable for use in winter time, for example at an angle selected between 60° and 75° from the horizontal; during the summer the peak current generated by the solar panel 24 will be reduced (because the sunlight is not incident on the normal) but on the other hand the hours of daylight are longer, and the night time (when electricity is not generated) is shorter, which tend to compensate for the reduction in peak current.

At higher latitudes, for example north of latitude 54° N, it may be advantageous to combine a wind rotor with solar cells. For example a bus stop as shown in figure 1 might include a wind rotor on top of the box 22 (instead of the solar panel 24), and might include several photovoltaic solar cells mounted on sides of the post 12. Alternatively a solar panel may be mounted on one side of the box 22 and a wind rotor mounted on the opposite side. On the other hand, at lower latitudes, for example south of latitude 40° N, the sunlight may be sufficiently bright that provision of a separate inclined solar panel 24 may not be necessary, and instead multiple solar cells may be mounted on the upper part of the post 12. In any event it will be appreciated that the present invention almost always reduces the amount of electricity needed to operate each day, as compared to a display system that merely goes into standby when it is not in active use, and so reduces the size of solar panel or the number of solar cells needed to provide the requisite amount of electricity.

Claims

1. A display system comprising an electronic display device, and a source of electricity for the electronic display device, wherein the system also comprises a circuit to provide electricity to the electronic display device, the circuit being actuated in response to input from a user, and subsequently being arranged to terminate the provision of electricity to the electronic display device after a delay interval, so that the electronic display device is off and uses no electricity.

2. A system as claimed in claim 1 wherein the circuit includes an actuating button whereby a user can create an electrical connection, to initiate operation of the electronic display device, and the circuit also including a relay component providing a connection in parallel to that provided by the actuating button, wherein the electronic display device is arranged to provide a control signal to the relay component to actuate the parallel connection, and is subsequently arranged to terminate the control signal to deactivate the parallel connection, so the circuit provides no electricity to the electronic display device.

3. A system as claimed in claim 2 wherein the relay component is an optocoupler.

4. A system as claimed in any one of the preceding claims wherein the electronic display device is a microcomputer connected to a display module.

5. A system as claimed in any one of the preceding claims which comprises a rechargeable battery as a source of electricity for the electronic display device, and an environmental energy source to provide electricity to the rechargeable battery.

6. A system as claimed in any one of the preceding claims wherein the delay interval, after which the electronic display device is off and uses no electricity, is less than 5 minutes but at least 10 seconds.

7. A system as claimed in any one of the preceding claims wherein the electronic display device is a touch-screen device, and the delay interval is restarted each time a user touches the screen.

8. A structure incorporating a system as claimed in any one of the preceding claims, wherein the system comprises a rechargeable battery as the source of electricity for the electronic display device, and an environmental energy source to provide electricity to the rechargeable battery is mounted on top of the structure.

9. A system substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.