AU2004100938A4 - Solar-Powered Sign - Google Patents

Description

2710/2004 12:13 61-3-9986-7680 MORCOM PERNAT PAGE 05/19 00 0

O

(-N

I

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION INNOVATION PATENT "Solar-Powered Sign" The following statement is a full description of this invention, including the best method of performing it known to me: COMS ID No: SBM1-00972996 Received by IP Australia: Time 12:18 Date 2004-10-27 27/10/2004 12:13 61-3-988-7O8 MORCOM PERNAT PAGE 86/19 o 2 Solar-Powered Sign 0 Background and Summary of the Invention o 5 This invention concerns the use of self-illuminated signs which use electric power en stored from solar collectors using photovoltaic cells. It is particularly useful for signs o which indicate the number a property (eg. a house number) in a street.

OOutdoor signs impose special restrictions on design. They must resist attack by vandals, be maintenance free and economical to install and run. A particular problems exists if one wishes to have a self-illuminated house number display powered solely by electricity generated from solar energy. Orienting an array of photovoltaic cells to optimize energy production requires a large horizontal projection. This is in contrast with the normal desire to have a sign in which horizontal projection is minimized.

Most signs require a vertical front display face and many require positioning in shaded areas or positioning on walls so that they see little or no direct sunlight. It has hitherto proven difficult to provide sufficient solar power electricity generation to satisfactorily illuminate such a sign throughout the night, particularly if there is a string of consecutive days which are heavily overcast and thus provide relatively little insolation. Photovoltaic solar collector panels may be located distant from the sign but wiring these to the sign is inconvenient, time consuming and leaves the assembly open to damage relatively easily.

An aim of the present invention is to provide a sign which overcomes these difficulties.

Accordingly, in one aspect the invention provides a self-illuminatable sign comprising: a generally flat tile-shaped housing having a front face, a window in said front face, COMS ID No: SBMF-00972996 Received by 1P Australia: Time 12:18 Dale 2004-10-27 27/10/2004 12:13 61-3-9f89-7600 MORCOM PERNAT PAGE 07/19 o 3 a sheet of light transparent material covering said window, said sheet o having a pair of planar main faces and having a light receiving edge, I> a planar array of photovoltaic cells mounted within said housing and immediately behind said sheet and extending for at least substantially the 5 full extent of said window, 00 Cfl3 an electric storage battery within the housing and connected to store o electrical energy generated by said array, indicia provided on one face of the sheet such that the indicia obscures oportion of the array, a light source formed of at least one light emitting diode arranged to direct light through said light receiving edge to illuminate the indicia, and means for activating said light source from said battery when electrical output from said array falls below a predetermined level.

IS The means for activating the light source may cause the light source to flash such that it illuminates the indicia no more than 50% of the time. The sign may be a house number display with the indicia being a numeral or numerals removably adhered to the outside face of said sheet.

Preferably the means for activating the light source includes a printed circuit board, the light source is affixed to the printed circuit board, and the printed circuit board and the battery are retained within the housing and generally in the plane of said transparent sheet and said array.

Brief Description of the Drawings In order that the invention may be more fully understood there will now be described, by way of example only, preferred embodiments and other elements of the invention with reference to the accompanying drawings where: Figure 1 is an isometric view from below showing an illuminated sign according to one embodiment of the present invention; COMS JD No: SBMI-00972996 Received by IP Australia: ime 12:18 Date 2004-10-27 27110/2004 12: 13 27/1/200 12:3 -3-92293I-7G00 MORCOM PERNAT PG 91 PAGE Oe/19 o 4 Figure 2 is an exploded view of the sign shown in Figure 1 when viewed from o the front; Figure 3 is an exploded view of the sign shown in Figure 1 when viewed from the rear; and 00 Figure 4 is a circuit diagramn for the electronic components in the sign.

o Description of Examples of the Invention and the Preferred Embodiment o Referring to Figure 1, the sign 10 has a housing 12 moulded in two parts 20 and 22 010 from plastics material. A window 14 in the front of the housing 12 is covered by a transparent polycarbonate sheet 16 which fonns a cover on the window. Adhered to the front of the sheet 16 are three digits which together fonrn a house number 18. The indicia. forming the house number 18 are cut from adhesive white vinyl film and arc firmly but removably adhered to the front of the sheet 16. The numerals may be removed and replaced if the property owner moves and wishes to take the sign with them and display the new number of their new property.

The housing 12 has a front cover portion 20 and a removable solid back panel 22.

The housing 12 has three holes for three screws 46 to be used to hold the sign onto the front of a house or other real estate property. Two of the screws pass through holes which pas through the front cover portion 20 of the housing and the back panel 22 of the housing. One screw passes through a hole 47 through a lug 21 on -the bottom of the front cover portion Immediately behind the transparent sheet 16 a rectangular photovoltaic array 24 is pressed against the rear face 26 of the sheet 16 by the ba ck panel 22. A recess 28 is formed within and at the rear of the front cover 20 and within this is located a battery pack 30 and a small rigid printed circuit board 32 on which is mounted the remaining electronic components.

The printed circuit board 32 is located within the lower portion of the recess 28.

From the centre of the underside of the circuit board 32, a white Light Emitting Diode COMS ID No: SBMI-00972996 Received by IP Australia: lime 12:18 Date 2004-10-27 27/10/2004 12: 13 61-3-9886-7600 MORCOM PERNAT PAGE 09/19 0 ci (LED) 34 protrudes downward into a notch 36 formed into the centre of the top edge 0 of the transparent sheet 16. The notch 36 and LED 34 are obscured from view from the front of the sign by a downward extending tongue 38 on the front face 40 of the front cover portion 00 Mfl The bottom edge 42 of the back panel 22 is located in front of a small lip 44 and the o back panel is glued or otherwise affixed to the front cover portion 20. Sealant is applied around the edge of the transparent sheet 16 to ensure weather sealing of the o sign and the join between the back panel 22 and front cover 20 is likewise sealed by 0 I0 either thermal fusion or by application of a sealant Caps 48 are applied to the heads of the screws 46 for cosmetic purposes.

Referring now to Figure 4, the photovoltaic array 60 is a model SC152152 manufactured by Sinonar of Taiwan and operates at 7.2 volts and 120 mA. The battery 62 consists of four NiMH AAA cells and has an output of 4.8 volt and capacity of 550 mAH.

The preferred embodiment described has a photovoltaic array of 150mm x 150=am and a window maximum height of 147mm and width of 147mm.

The electronics are chosen so that the voltage being produced by the photovoltaic array is monitored and when it drops below a given threshold value (ie when it gets dark enough), the LED illumination is activated. The illumination is deactivated again when the voltage output from the photovoltaic array rises above a chosen set value. The two set values are spaced, and a timing sequence may be introduced, in order to prevent multiple switching of the circuit during periods when the ambient light is varying slightly around the set values during approaching darkness and approaching dawn.

The circuit shown in Figure 4 is for steady light output from the LED 34 but may be readily adapted by a skilled technician to produce a flashing output. In one preferred COMS ID No: SBMI-00972996 Received by IP Australia: Time 12:18 Date 2004-10-27 27/10/2004 12:13 27/&2B4 1:13 61-3-SBOG-7908 MORCOM PERNAT RG 01 PAGE le/19 o 6 farm of the invention, the flashing LED 34 remains on for one second and then off for 0 two seconds.

The sign 10 has the shape of a flat rectangular prism, much like the shape of a flat tile.

00 5 The sign is kept desirably thin by means of mounting the circuit board 32 and the en storage battery 3U in a recess 28 which is generally co-planar with the transparent o sheet 16 and photovoltaic array 24. This also pernits easy location of the LED 34 0 within the notch 36 even though the LED is rigidly attached to the circuit board -32.

o The piano of the circuit board 32 may be parallel to that of the array 24 but, if the 010 circuit board 32 is made sufficiently narrow it may be aligned perpendicular to the plane of the array 24 as shown in Figures 2 and 3.

Although the photovoltaic array 24 is obscured to a significant degrec by the overlying numbers IS, and therefore does not produce its maximum possible output for any given incident radiation, the sizing is sufficient for the unobseured elements in the photovoltaic array 24 to still provide sufficient power for the purpose intended- It has been found that. even in situations where no direct sunlight falls upon the photovoltaic array, such as on the south facing wall of a house in Melbourne Australia or in situations where shaded by tree cover, a sign of this type can operate indefinitely lighting the sign all night.

In situations where the sign is exposed to bright direct sunlight for many hours each day, the user may prefer the light to be illuminated constantly during the night.

However, in lower incident light conditions, the user may prefer the alternative of intermittent activation of the LED in order to reduce the power requirements of the display. A sequence of one second on and two seconds off has been found sufficient and has the additional advantage that the flashing nature of the light attracts attention from those looking to find the house number. A one second period of lighting has been found sufficient for easy visual identification of the house number.

Whilst the above description includes the preferred emhodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions COMS ID No: SBMI-00972996 Received by IP Australia: lime 12:18 Date 2004-10-27 27/11/2004 12:13 61-3-99B6-7681 MORCOM PERNAT PAGE 11/19 o 7 0 may be introduced into the constructions and arrangements of parts previously 0 described without departing from the essential features or the spirit or -ambit of the invention.

ci s It will be also understood that where the word "comprise", and variations such as O0 0"3 "comprises" and "comprising", are used in this specification, unless the context 2 requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge in Australia.

Finally it is to be understood that various alterations, modifications and/or additions may be incorporated into the various constructions and arrangements or parts without departing from the spirit and ambit of the invention, COMS ID No: SBMI-00972996 Received by IP Australia: Time 12:18 Date 2004-10-27

Claims (1)

1. 61-3-9986-7600 MORCOM F'ERMAT PAGE 12/19 0 8 o9 0 (-N SThe claims defining the invention are as follows: 0 l I. A self-illuminatable sign comprising: a generally flat tile-shaped housing having a front face, o0 a window in said front face, n a sheet of light transparent material covering said window, said sheet 2 having a pair of planar main faces and having a light receiving edge, a planar array of photovoltaic cells mounted within said housing and 0immediately behind said sheet and extending for at least substantially the C, 10 full extent of said window, an electric storage battery within the housing and connected to store elctrical energy generated by said array, indicia provided on one face of the sheet such that the indicia obscures portion of the array, a light source formed of at least one light emitting diode arranged to direct light through said light receiving edge to illuminate the indicia, and means for activating said light source from said battery when electrical output from said array falls below a predetermined level. 2 A self-illuminatable sign according to claim 1 wherein said means for activating the light source causes the light source to flash such that it illuminates the indicia no more than 50% of the time. 3. A self-illuminatable house number display according to claim 1 or claim 2 wherein the indicia are a numeral or numerals removably adhered to the outside face of said sheet. 4. A self illumintable sign according to any one of claims 1 to 3 wherein said means for activating the light source includes a printed circuit board, said light source is affixed to the printed circuit board, and said printed circuit board and said battery COMS ID No: SBMI-00972996 Received by IP Australia: Time 12:18 Date 2004-10-27 27/10/204 12:13 61-3-9886-7600 MORCOM PERNAT PAGE 13/19 9 are retained within the housing and generally in the plane of said transparent sheet and said array. A self illumintable sign identifying a real estate property number substantially as hereinbefore described with reference to Figures 1 to 3 of the accompanying drawings. Dated this 27th day of October 2004 Charles Robert Hook by his patent attorneys Morcom Pernat COMS ID No: SBMI-00972996 Received by IP Australia: Time 12:18 Date 2004-10-27