CROSS REFERENCE TO RELATED APPLICATION(S)This application is a Continuation of U.S. patent application Ser. No. 11/102,229 filed on Apr. 7, 2005, now U.S. Pat. No. 7,429,827, which is a Continuation-In-Part of U.S. patent application Ser. No. 10/789,488, filed on Feb. 26, 2004, now U.S. Pat. No. 7,196,477, which claims priority to Australian Patent Application No. 2003271383, filed on Dec. 23, 2003, which are all incorporated herein by reference.
TECHNICAL FIELDThe present invention relates to solar powered lights and more particularly but not exclusively to solar powered lights that produce a light of varying colour.
BACKGROUND OF THE INVENTIONLight devices that employ light emitting diode (LED) systems to produce a variable colour are known. Examples are described in U.S. Pat. Nos. 6,459,919, 6,608,458, 6,150,774 and 6,016,038. It is also known to have “garden lights” that are solar powered. For example such garden lights include a body providing a spike that is driven into a ground surface. At the upper end of the spike there is mounted a diffuser surrounding a lamp, with the lamp being driven by rechargeable batteries and a solar cell.
The abovementioned lighting apparatus have a number of disadvantages including difficulty in adjusting the various lighting functions and not producing a uniform desired colour when required to do so.
OBJECT OF THE INVENTIONIt is the object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages.
SUMMARY OF THE INVENTIONThere is disclosed herein a lighting device to produce light of varying colour, said device including:
a body;
a lens mounted on the body and generally enclosing a chamber having an upper rim surrounding a top opening, and a bottom region;
a reflector mounted in the bottom region;
a cap assembly including securing means to releasably engage the rim so that the cap assembly can be selectively removed from the lens; said assembly including:
a base;
a circuit having at least two lamps of different colours which are activated to produce a desired colour including a varying colour, the lamps being mounted to direct light into said chamber, a solar cell mounted on an exposed surface of the assembly and rechargeable batteries to power the circuit, a light sub-circuit connected to the lamps to deliver electric power thereto so that the lamps produce said desired colour, and a switch operable to deliver electric power from the batteries and cell to said sub-circuit, the switch being exposed to provide for access thereto by a user.
Preferably, said circuit includes a light sensitive switch that renders the circuit operation at low light levels.
Preferably, said switch is on an exposed downwardly facing surface.
Preferably, said circuit includes three lamps, each of a different colour.
Preferably, said lens is a first lens, and said device includes a second lens, said second lens being attached to said base and providing a cavity into which the LEDs direct light, with the light leaving said second lens then passing through said first lens.
Preferably, the first and second lenses diffuse light.
Preferably, said body includes a post having opposite first and second ends, with a spike attached to said first end, and said first lens attached to said second end.
Preferably, said second lens is detachably secured to said post.
Preferably, said switch is a first switch, and second sub-circuit includes an integrated circuit and a second switch connected to said integrated circuit, the second switch being exposed to provide for access thereto by a user.
Preferably, said second switch activates said integrated circuit to select a desired colour.
Preferably, said second switch is on said exposed surface.
There is further disclosed herein a lighting device to produce light of varying colour, said device including:
a body;
a lens mounted on the body and generally enclosing a chamber;
a circuit having at least two lamps of different colours to produce a desired colour including a varying colour, the lamps being mounted to direct light into said chamber, connections for at least one rechargeable battery to power the circuit and a solar cell mounted on an exposed surface of the assembly and operatively associated with the connections to charge the battery, and a switch operated to control delivery of electric power from the battery to operate said circuit, the switch being exposed to provide for access thereto by a user.
Preferably, said circuit includes a light sensitive switch that renders the circuit operative at low light levels.
Preferably, said circuit includes a light sub-circuit connected to the lamps to deliver electric power thereto so that the lamps produce said desired colour, with said switch being an on/off switch to deliver electric power from the batteries to said sub-circuit.
Preferably, said circuit includes a light sub-circuit having an integrated circuit operable to select a desired fixed colour, with said switch being connected to said integrated circuit and operable to select said desired fixed colour.
Preferably, said circuit includes a sub-circuit, said switch is a first switch said first switch being an on/off switch to deliver electric power from the battery to said sub-circuit, and said sub-circuit includes an integrated circuit and a second switch connected to said integrated circuit, the second switch being operable to select a desired fixed colour and exposed to provide for access thereto by a user.
Preferably, said second switch is on said exposed external surface.
There is further disclosed a lighting device to produce light, said device including:
a base;
a lens mounted on the base and generally enclosing a chamber;
a circuit having at least one lamp to produce a light, the lamp being mounted to direct light into said chamber, connections for at least one rechargeable battery to power the circuit and a solar cell exposed to said chamber so as to receive light passing through said lens and operatively associated with the connections to charge the battery, and a primary switch operable to control to operate said circuit;
a battery compartment including a cavity to receive said battery and having said contacts;
a closure member attached to said compartment but movable relative thereto to expose said cavity to provide for insertion of said battery; and wherein
said switch is exposed to said cavity so that upon movement of said closure member to expose said cavity, a user has access to said switch to operate the switch.
Preferably, device has at least two lamps to produce light of a desired colour including a varying colour.
Preferably, said circuit includes a light sensitive switch that renders the circuit operative at low light levels.
Preferably, said circuit includes a light sub-circuit connected to the lamps to deliver electric power thereto so that the lamps produce said desired colour, with said switch being an on/off switch to deliver electric power from the batteries to said sub-circuit.
Preferably, said circuit includes a light sub-circuit having an integrated circuit operable to select a desired fixed colour, with said switch being connected to said integrated circuit and operable to select said desired fixed colour.
Preferably, said circuit includes a sub-circuit, said switch is a first switch said first switch being an on/off switch to deliver electric power from the battery to said sub-circuit, and said sub-circuit includes an integrated circuit and a second switch connected to said integrated circuit, the second switch being operable to select a desired fixed colour and exposed to provide for access thereto by a user.
Preferably, said second switch is on said exposed external surface.
Preferably, said circuit includes a light sub-circuit connected to the lamps to deliver electric power thereto so that the lamps produce said desired colour, with said primary switch being an on/off switch to deliver electric power from the batteries to said sub-circuit.
Preferably, said circuit includes a light sub-circuit having an integrated circuit operable to select a desired fixed colour, with said integrated circuit being connected to a sub-circuit switch, the sub-circuit switch being operable to select said desired fixed colour.
Preferably, said circuit includes a sub-circuit, said primary switch is a first switch said first switch being an on/off switch to deliver electric power from the battery to said sub-circuit, and said sub-circuit includes an integrated circuit and a second switch connected to said integrated circuit, the second switch being operable to select a desired fixed colour and exposed to provide for access thereto by a user.
Preferably, said second switch is exposed to said chamber.
Preferably, said lens is fixed to said battery compartment and said battery compartment threadably engages said closure member so that relative rotation between the closure member and said compartment moves said closure member between an open position exposing said cavity and a closed position closing said cavity.
Preferably, said closure member includes a socket, and said device includes a spike engaged in said socket and projecting therefrom to provide for the spike to be inserted in a ground surface so that the device is supported thereby.
BRIEF DESCRIPTION OF THE DRAWINGSA preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein:
FIG. 1 is a schematic side elevation of a lighting device;
FIG. 2 is a schematic sectioned front elevation of the device ofFIG. 1;
FIG. 3 is a schematic sectioned side elevation of the device ofFIG. 1;
FIG. 4 is a schematic plan view of a moulding employed in the device ofFIG. 1;
FIG. 5 is a schematic plan view of a base member of the device ofFIG. 1;
FIG. 6 is a schematic to plan view of a cap assembly employed in the device ofFIG. 1;
FIG. 7 is a schematic isometric view of a lens employed in the device ofFIG. 1;
FIG. 8 is a schematic isometric view of a second lens employed in the device ofFIG. 1;
FIG. 9 is a circuit diagram of the circuit of the board ofFIG. 4;
FIG. 10 is a schematic perspective view of an ornamental garden light.
FIG. 11 is a schematic side elevation of a further lighting device;
FIG. 12 is a schematic side elevation of the lens portion of the device ofFIG. 11; and
FIG. 13 is a schematic sectioned side elevation of portion of the device ofFIG. 11.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSInFIGS. 1 to 9 of the accompanying drawings there is schematically depicted alighting device10. Thedevice10 of this embodiment is configured as a “garden light”. Thedevice10 includes abody11 including apost12 from the lower end from which there extends aspike13. Thespike13 is driven into a ground surface so that thepost12 is exposed above the ground surface.
Attached to the upper end of thepost12 is alens assembly14. Thelens assembly14 includes alens15 that encompasses achamber16. The lower end of thelens15 has fixed to it a “bayonet” fitting17 that engages ashaft18 fixed to the upper end of thepost12. The fitting17 includes an “L” shapedslot19 through which theshaft18 passes to secure thelens assembly14 to the upper end of thepost12.
Thechamber16 includes alower portion20 within which there is mounted anarcuate reflector21 that is concave.
Thelens15 has arim22 surrounding theupper opening23 of thelens15.
Removably attached to therim22 is acap assembly24. Theassembly24 includes acover25 fixed to abase26. Thebase26 is located beneath thecover25 and is shielded thereby. Thebase26 and cover25 encompass achamber27 within which there is a mountedmoulding28. Themoulding28 is provided with battery compartments32. The components of thecircuit29 are located within thechamber27, while the upper surface of theassembly27 is provided with thesolar cell30. Thecell30 is exposed through a centralrectangular aperture31 of thecap25.
Mounted within thechamber27 via battery compartments32 arerechargeable batteries33 which are used to energise threeLEDs34. TheLEDs34 when illuminated produce red, green and blue light.
Thecap assembly24 is generally circular in configuration so as to provide thedevice10 with a generally verticallongitudinal axis35.
Thebase26 has radially inward projectingflange segments36 that engage with radially outward extendingflange segments37 of therim22 to be secured thereto. By angular movement of thecap assembly24 about theaxis35, thesegments36 and37 engage or disengage to secure or to release theassembly24 with respect to thelens15. As can be noted fromFIG. 5, theflange segments37 haveend abutment portions38 against which thesesegments36 engage when theassembly24 is secured to thelens15.
As can be noted fromFIG. 6, mounted on the under surface of thebase26 is asecond lens38. Accordingly, theLEDs34 when activated have their light preferably diffused by thelens38 and then further diffused by thelens15. This in particular aids in producing a more evenly coloured light when theLEDs34 are activated.
Thecircuit29 powers and controls thelighting device10 in accordance with an embodiment of this invention. Thecircuit29 consists of a number of interconnected sub-circuits, including a power supply circuit, a light operated circuit, a boost-up circuit, a rectifier circuit, and a light circuit.
The power supply circuit comprises asolar cell30 connected in series to a forwardbiased diode39, which is in turn connected to a positive terminal of abattery33. A negative terminal of thebattery33 is then connected to thesolar cell X30 to complete the power supply circuit. In this example, thediode39 is a model number IN5817 Schottky diode and the battery comprises two rechargeable 1.2 volt battery cells. It will be apparent to a person skilled in the art that other diode and battery configurations may be utilised without departing from the spirit and scope of the invention.
When thesolar cell30 is exposed to sufficient light, the solar cell converts some of the solar energy to electrical energy and creates a current that passes through thediode39 to charge thebattery33. Thus, during the day thesolar cell30 converts energy from the sun to charge thebattery33. Thediode39 prevents thebattery33 from expending any power on thesolar cell30.
The power supply circuit is connected in parallel to the light operated circuit, which is connected across the terminals of thebattery33. The positive terminal of thebattery33 is connected to aswitch40, which is in turn connected to a 100 kΩfirst resistor41. Thefirst resistor41 is connected in series with a second, light-dependent resistor42. Thesecond resistor42 connects to the negative terminal of thebatteries33 to complete the light operated circuit. The value of resistance of thesecond resistor42 depends on the amount of light to which thesecond resistor42 is exposed. When there is not much light, such as occurs during the night, the value of thesecond resistor42 increases. During the daytime, when there is sufficient light, the value of thesecond resistor42 decreases. Accordingly theresistor42 allows the lighting device to operate only when there is insufficient light, ie night.
The boost-up circuit is connected to the light operated circuit, in parallel with thefirst resistor41 and the second, light-dependent resistor42. Afirst circuit node43 is defined between theswitch40 and thefirst resistor41. Connected to thenode43, is an emitter terminal of afirst triode44. A collector terminal of thefirst triode44 is connected in series with a 100 kΩ third resistor45. The third resistor45 is then connected to a point between thefirst resistor41 and thesecond resistor42.
A 220 kΩfourth resistor46 is connected tonode43 across the emitter and base terminals of thefirst triode44. In parallel with thefourth resistor46, and also connected across the emitter and base terminals of thefirst triode44, is a 4.7 nFfirst capacitor48. Further connected tonode43, across the emitter and base terminals of thefirst triode44 and in parallel with each of thefourth resistor46 and thefirst capacitor48, is a 100μH inductor49 in series with a 1 nFsecond capacitor50. The second capacitor is then connected to the base terminal of thefirst triode44.
A 20 kΩfifth resistor51 is connected across the base and collector terminals of thefirst triode44. Connected across the terminals of the third resistor45 are the collector and base terminals, respectively, of asecond triode52. The emitter terminal of thesecond triode52 is connected to the negative terminal of thebatteries33.
Connected between theinductor49 and thesecond capacitor50 is the collector terminal of athird triode53. The base terminal of thethird triode53 is connected via an intermediary circuit to the collector terminal of thesecond triode52. The intermediary circuit consists of a 2.4 kΩfourth resistor54 in parallel with a 1 nFthird capacitor55. The emitter terminal of thethird triode53 is connected to the negative terminal of thebattery33.
Also connected between theinductor49 and thesecond capacitor50 is the rectifier circuit. A forward biasedsecond diode56 is connected to a point between theinductor49 and thesecond capacitor50, and then to a positive terminal of a 33 μFfourth capacitor57. The negative terminal of thefourth capacitor57 is connected to the negative terminal of thebattery33. Asecond circuit node58 is defined between thesecond diode56 and thefourth capacitor57. Connected in parallel with thefourth capacitor57, between thesecond node58 and the negative terminal of thebattery33 is a reverse biased 4.5Vthird diode59. Thesecond diode56, thefourth capacitor57 and thethird diode59 comprise the rectifier circuit. Further connected to thesecond circuit node58, in parallel with each of thecapacitor57 and thereverse diode59, is alight circuit60.
Thelight circuit60 contains an integrated circuit (IC)61 for controlling lighting effects provided by thelighting device10. In the embodiments shown, theIC61 is a 16-pin, three colour LED IC for controlling first, second and third light emitting diodes (LEDs)34A,34B and34C. Each ofpins1,15 and16 is connected in series torespective switches69,70,71. Each of theswitches69,70 and71 is then connected to the negative terminal of thebattery33. In one embodiment, theswitches69,70,71 correspond to theLEDs34A,34B, and34C to enable or disable a particular colour range. In another embodiment, theswitches69,70,71 determine the frequency of a colour changing effect. In a further embodiment, theswitches69,70,71 determine the intensity of light emitted by each of theLEDs34A,34B, and34C. Various combinations of the frequency and intensity of light are also possible. Theswitches69,70,71 can be made accessible to a user to create custom lighting effects. Alternatively, theswitches69,70,71 are set according to a predetermined configuration and are not readily accessible by a user.
Pin4 of theIC61 enables an optional pause function. In this embodiment, pin4 connects to apush button65 that is, in turn, connected to the negative terminal of thebatteries33. Pin3 of theIC61 connects to thesecond circuit node58.
Connected to thesecond circuit node58, and in parallel with one another, are the first second and third forward biased light emitting diodes (LEDs)34A,34B and34C. Thefirst LED34A is connected in series with asixth resistor66 that is connected to pin13 of theIC61. Thesecond LED34B is connected in series with aseventh resistor67 that is connected to pin12 of theIC61. Thethird LED34C is connected in series with aneighth resistor68 that is connected to pin11 of theIC61. In this example, thefirst LED34A is blue, thesecond LED34B is green and thethird LED34C is red.
Pins6 and8 of theIC61 are tied to one another via aninth resistor72, which in the embodiment shown is a 20 kΩ resistor. The valve of theninth resistor72 determines the frequency of a colour change created by theIC61. Accordingly, using different resistor valves for theninth resistor72 produces colour changes of different frequencies. Pin9 of theIC61 is tied to the negative terminal of thebattery33.
During the day, thesolar cell30 charges thebattery33. The value of thesecond resistor42 is low and, consequently, small amounts of current flow through the boost-up circuit, rectifier circuit and light circuit. As night falls, the amount of energy converted by thesolar cell30 decreases. The resistance of thesecond resistor42 increases and more current flows into the boost-up circuit, rectifier circuit and light circuit. This activates theLEDs34A,34B, and34C in the light circuit and thelight device10 produces a changing light effect.
Theintegrated circuit61 controls each of the first, second andthird LEDs34A,34B, and34C to produce a changing light effect for thelight device10. The integrated circuit varies the frequency and intensity of light emitted by theLEDs34A,34B, and34C to produce a constantly changing kaleidoscopic effect. Thelight device10 displays a constantly changing lighting effect that cycles through the light spectrum by ramping up and ramping down the intensity of light displayed by theLEDs34A,34B, and34C.
Connecting the optional pause function of pin4 of theIC61 to thepush button65 enables a user to stop the changing light effect and maintain a constant colour. In this manner, a user can select a preferred colour for a lighting effect. The user observes the changing colour effect and when a desired colour is displayed, the user depresses thepause button65.
The colour displayed at the time that the button is pressed then remains on. Preferably, the circuit retains sufficient charge such that a user selected colour is retained during the day and is displayed again when the light is reactivated the following evening. In this manner, the user does not have to reselect a desired colour each night. To reinstate the changing light effect, the user presses thepush button65 again and the changing light effect resumes.
In the embodiment shown inFIG. 9, thebattery33 powers thelight circuit60 during the night to produce light of varying colours and the user can optionally select a desired colour by pushing thepush button65. A selected colour is retained by memory in theIC61. The memory may be a switch. Whilst the battery is powering thelight circuit60, thefourth capacitor57 stores charge. As stated above, it is desirable for a selected colour to be retained and displayed on successive nights. As thebattery33 discharges, the output voltage of thebattery33 decreases. When the output voltage of thebattery33 is less than the stored voltage of thecapacitor57, thecapacitor57 discharges. Due to the presence and arrangement of thediodes56 and59, thecapacitor57 discharges through thelight circuit60.
TheIC61 preferably includes a cut-off circuit that is voltage dependent. As thecapacitor57 discharges, the voltage across the cut-off circuit decreases. Once the voltage across the cut-off circuit reaches a predetermined threshold value, the cut-off circuit prevents further power being consumed by the LEDs. As no power is being consumed by thelight circuit60, thecapacitor57 retains a residual charge. The residual charge maintains a voltage across theIC61, which enables the selected colour to be retained by the memory in theIC61.
During the next day, thesolar cell30 recharges thebattery33. As night falls, the resistance ofresistor42 again increases and thebattery33 provides sufficient power to thelight circuit60 to increase the voltage across the cut-off circuit above the predetermined threshold value. The LEDs are activated and the selected colour, as retained in the memory of theIC61, is displayed. The voltage provided by thebattery33 is more than the stored charge of thefourth capacitor57, so thecapacitor57 again begins to store charge.
It will be readily apparent to a person skilled in the art that there are many circuit variations possible for enabling and controlling the lighting display, without departing from the spirit and scope of the invention.
Theswitch40 and/or switch65 is/are mounted on the base26 so as to be on a downwardly facing external surface of thebase26. This enables a user to control the device via readily accessible switches, without needing to remove thecap assembly24. Theswitches40 and65 are each operable to control delivery of electric power from the batteries to theLEDs34A,34B and34C. Thecircuit29 is only rendered operative when there is insufficient light, that is, by operation of a light sensitive switch, ie thediode43.
The embodiment ofFIG. 10 includes anornamental garden light73 having a body orbase74. The base74 would be at least partly hollow so as to contain the circuitry ofFIG. 9, except for thesolar cell30. Thesolar cell30 would be mounted so as to be exposed to sunlight. Theswitches40 and65 would be mounted at an external surface of thebase74.
Theswitch40 and/or switch65 would be mounted on an external surface of thebase74, while thediode42 would be exposed to sunlight.
Thebase74 includes aspherical lens75 secured to ahorizontal portion76 of thebase74. Thehorizontal portion76 would have mounted in it theLEDs34A,34B and34C so as to deliver light to the interior of thelens75.
InFIGS. 11 to 13 there is schematically depicted a lighting device100 that is a modification of the previously described lighting devices.
The lighting device100 employs the circuit ofFIG. 9.
In this embodiment, the lighting device100 includes alens101 of generally spherical form consisting of alower portion102 fixed to anupper portion103. Askirt104 abuts thelower portion102.
Thebase106 includes abattery compartment110 providing acavity111 within which abattery holder112 is located and supports thebatteries33. Thebattery compartment110 is closed by aclosure member109 that acts as a cap or lid closing thecavity111. Themember109 includes apad113 that abuts thebatteries33 to aid in retaining them in position.
Aspike105 extending from theclosure member109 and is provided to penetrate an earth surface to secure the device100 in position.
Themember109 has asocket107 within which the upper portion of thespike105 is slidably received. Thespike105 engages theskirt104 and holds theskirt104 abutting thelower portion102.
Flanges108 extend from thesocket107 and are fixed to anupper flange120 of theclosure member109 to reinforce thesocket107.
Thelens101 encloses achamber114 to which thesolar cell30 is exposed so that thesolar cell30 receives light through thelens101. Located adjacent thesolar cell30 but not illustrated is a circuit board having thecircuit29.
Mounted on thebattery compartment110 are the LEDs34a,34band34cthat are protected by means of atranslucent diffuser115.
Mounted on thebattery compartment110 is theswitch40 and/or switch65 of thecircuit29.
Thebattery compartment110 includes a generally circular internally threadedflange116 that threadably engages acircular flange117 of thebase106.
In respect of the above preferred embodiment, thebattery compartment110 is integrally formed with thelower portion102 and engages the base106 by means of anannular seal118 to sealingly connect the base106 to thebattery compartment110.
To provide access to thebatteries33 and switches40 and65, thelens101 is rotated about theaxis119 relative to the base106 so there is relative movement between theflanges116 and117. This relative movement removes the base106 from thelens101. Accordingly a user may then manipulate theswitches40 and65.
In the above embodiment, themember109 is moved relative to the base106 from a closed position, relative to thecavity111, to at least a partly open position providing access to theswitches40 and65.