FIELD OF THE INVENTION

The present invention relates to LED based lighting system in the form of a DC / Solar operated tube light device suitable for office/rural home lighting. More particularly, the present invention relates to a DC (Battery) / solar powered LED tube light device, wherein a plurality of LEDs as light sources is arranged in the form of a one line array. This device can be produced in standard lengths of 2 ft and / or 2.5 ft with a Poly methyl methacrylate (PMMA) diffuser or a clear transparent casing. The number of LEDs in a device depends on the light output specifications such as 51 numbers of LEDs are used in a lighting device to produce 500 lumen light output in an example case. Advantageously, this LED tube light device requires no lighting fixture or starter / choke (ballast) as of conventional fluorescent tubes. Only one connector pin at one end is used to connect the device to the battery or a source for DC power. The tube light can be mounted easily at any suitable location on the wall or roof with a couple of clamps or tube holders. The LED tube light consumes low power and has a long life compared to the conventional lights. This DC/solar powered LED tube light device is thus having prospects of wide scale application and use in rural lighting and standby lights in homes / office complexes and particularly in places where grid power is not available but plenty of sun light is available such as in the rural households.

BACKGROUND OF THE INVENTION
Use of fluorescent tube lights is quite common in lighting application in home/offices for brighter and wider spread of uniform illumination. Conventional Tube lighting devices are available in 4 ft or 2 ft lengths which comprise of a fixture, choke, starter and a fluorescent tube light which operates on the application of 230V AC from mains power supply of the Grid. The power consumption is of the order of 36W/40W for 4ft and 18W for 2ft tube lights.

It is well known that such conventional tube lights operate on the principles of electric discharge and take time to turn on. There is always flicker associated with the starting process for this tubes when put on. These lights have limited life and are entirely dependent on the availability of mains power for their operation. There is also pollution from the mercury used in the tubes. The initial cost of conventional tube lights also includes cost of the fixture, starter and the choke.

There has been thus a continuous need for low cost low powered standby /emergency lighting for homes and offices substituting the conventional tube lights powered by grid power (230V) while ensuring the desired illumination and all round wider area coverage. More specifically, the need existed for lighting household in rural areas where grid power is not available or has not reached. There has been a requirement in the art to developing a tube light which would consume low power from a battery or a DC source or a solar panel, provide instant lighting free of any flickering, produce no pollution due to mercury etc., and on the other hand would ensure easy installation, longer life, bright and larger area of illumination.

OBJECTS OF THE INVENTION
The basic object of the present invention is thus directed to developing a LED lighting system in the form of a tube light device for application in office/rural home lighting which would be powered by DC(Battery)/solar power, substituting conventional grid supply power based tube lights and also to provide light in rural areas in simple and cost effective manner with longer life.

Another object of the present invention is directed to providing a DC/Solar powered LED lighting system as a tube light device for home/offices as well as rural population without grid supply which would provide instant light free of any flickering whenever switched on, avoiding turn on delay.

A further object of the present invention is directed to providing a DC/Solar powered LED tube light device/lighting system in various sizes and configurations for a variety of applications extending from home or office lighting to emergency lighting to home lighting to the rural households, which would consume low power yet provide sufficiently bright illumination over wider area to carry out any kind of household or official work.

A Still further object of the present invention is directed to providing a DC/Solar powered LED tube light device/lighting system for home/offices as well as rural population which would not require any fixture, starter, choke etc. and thus save on costs.
A still further object of the present invention is directed to providing a DC/Solar powered LED tube light device/ lighting system for home/offices as well as rural population adapted to ensure longer operating life with less/no maintenance for both domestic or office application.

A still further object of the present invention is directed to providing a DC/Solar powered LED tube light device/ lighting system for home/offices as well as rural population which would ensure environment friendly operation free of any pollution due to mercury or carbon emissions during power generation or the like.

A still further object of the present invention is directed to providing a DC/Solar powered LED tube light device/ lighting system for home/offices as well as rural population adapted to providing emergency lighting and standby office lighting.

A still further object of the present invention is directed to providing a DC/Solar powered LED tube light device/ lighting system for home/offices as well as rural population which would ensure longer battery backup times due to low power consumption.

SUMMARY OF THE INVENTION
The basic aspect of the present invention is directed to a LED based lighting system comprising

an aluminium base supporting an assembly of LEDs on a PCB and adapted to serve as a heat sink, a cooperative LED driver electronics and an operating cable connecting to the power source.

Another aspect of the present invention is directed to said LED based lighting system comprising a DC (Battery) / Solar operated 2ft LED tube light comprising of said aluminium extruded base, said LED assembly on a PCB, said LED driver electronics, end caps and said operating cable connecting to the power source selected from (i) DC power source (ii) a battery and (iii) a solar panel through a charge control unit (CCU) and battery.

A further aspect of the present invention is directed to said LED based lighting system wherein said aluminium extruded base acts as a support for placing PCB containing the LED assembly with suitable glue or adhesive.

A still further aspect of the present invention is directed to said LED based lighting system wherein a driver PCB provides necessary power to drive the LEDs with constant current sources to produce desired light output.

A still further aspect of the present invention is directed to said LED based lighting system wherein a PMMA diffuser or a PMMA clear transparent tube provides a casing for the assembly enabling the light output from the LEDs to be dispersed uniformly.

Importantly in said LED based lighting system, the number and type of LEDs is based on the light output needed for an application.

According to an advantageous aspect of the present invention directed to said LED based lighting system wherein the length of the tube can be increased from 2ft up to accommodate more LEDs for more power and light output.

A still further aspect of the present invention is directed to said LED based lighting system wherein a SPV panel and a charge control electronics facilitate charging of the battery during the sunny hours to support the autonomy - the duration of lighting requirements during the non sunny hours.

According to an aspect of the LED based lighting system of the present invention, a clear transparent tube is used in place of the diffuser for more light on the target areas.

A still further aspect of the present invention directed to said LED based lighting system which is adaptable in various sizes and configurations for variety of applications extending from home or office lighting to emergency lighting to home lighting to the rural households. Advantageously, the LED based lighting system of the invention is extendable and configurable as per the desired end application and use in a very simple and convenient manner and very cost-effectively.

According to yet another aspect of the present invention directed to said LED based lighting system wherein the tube light can be used either with a DC source or a battery only or with a solar panel and battery.

According to a further advantageous aspect of the present invention directed to LED based lighting system adapted such that the same can be fitted to the ceiling or wall preferably with a couple of clamps dispensing with the need for fixture, choke and starter. Advantageously these lighting systems can be developed in various alternative combinations of flexible arrangements to serve any desired lighting requirements.
A still further aspect of the present invention is directed to said LED based lighting system wherein two such 2ft tube lights are operated with one set of SPV / CCU / Battery combination in a typical rural, home lighting application. It is also possible to connect more such tube lights with proper selection of higher capacities for SPV panel, CCU and battery.

The present invention and its objects and advantages are described in greater detail with reference to the following accompanying non limiting illustrative drawings:

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Figure 1: is the schematic block diagram showing the arrangement of various components of DC/Solar powered LED tube lights according to the invention.

Figure 2: is the schematic diagram showing the complete assembly of the DC/solar operated tube light according to the present invention.

Figure 3: is the schematic illustration of the exploded view of the DC/Solar powered tube light according to the present invention showing the different components used in the assembly of such lights.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING FIGURES
The present invention is directed to providing suitable DC(Battery)/solar powered 2ft LED tube light device for office/rural home lighting, wherein a plurality of LEDs as light sources are arranged in the form of a one line array.

Reference is first invited to the accompanying Figure 1 that illustrates the schematic block diagram showing the schematic connection arrangement of the basic components used in such a lighting system.

Reference is now invited to the accompanying Figure 2 that schematically shows the complete assembly of a DC(Battery)/Solar Panel operated LED tube light according to the invention. The typical length of such a tube light is either 2ft (60cm) or 2.5ft(75cm) according to the lighting need for any particular application.

Reference is next invited to the accompanying Figure 3 which shows the exploded view of the assembled LED tube light wherein individual components used in the assembly are clearly identified. The complete unit of a LED tube light comprising of an aluminium extruded base, an LED assembly on a PCB, LED driver electronics, end caps and a cable connecting to the DC power source or a battery or solar panel through a charge control unit (CCU) and battery.

The tube light according to the present invention has an aluminium extrusion(l) which works as base on to which the MCPCB(2) containing the LEDs (SMT / leaded) is fitted or glued using adhesive. The aluminium body acts as heat sink to drive away the heat dissipated inside the tube. The DC power supply or battery is connected from one end to the LED driver assembly by means of a cable. The casing(3) which covers the LED PCB and driver PCB(4) is made of either a diffuser of PMMA material or a fully transparent clear tube of PMMA material. The driver PCB provides necessary power to drive the LEDs with constant current sources to produce desired light output. The number and type of LEDs used in a PCB of LED tube light depends on the light output for a particular application. The use of a diffuser eliminates the glare and disperses the light output evenly for comfort of viewing. A clear transparent casing may also be used in place of a diffuser in which case the LEDs are visible with associated glare, but the light intensity will be better than that using a diffuser. The LED based lighting systems of the present invention are adaptable in various sizes and configurations for variety of applications extending from home or office lighting to emergency lighting to home lighting to the rural households.

The LED tube light according to the present invention can be used either with a DC source or a battery only or with a solar panel and battery. For use of the LED tube light device in conjunction with a solar panel, reference is made to the block schematic of Figure 1, wherein it is shown that the SPV module is connected to Charge Control electronics Unit (CCU) which enables and controls the charging of the battery from the solar panel. Protections for overcharging, undercharging and indications of charging / battery status etc. are provided in the CCU. Tube light is connected as load to the CCU and gets the battery power for operation. SPV panel and charge control electronics facilitate charging of the battery during the sunny hours to support the autonomy - the duration of lighting requirements during the non sunny hours.

In a typical rural household application, up to 2 tube lights of 2ft or 2.5ft length can be supported on a single SPV panel / CCU / Battery combination. This however cannot be construed as a limitation as by selecting proper higher capacities of the SPV panel, CCU and battery, any number of 2ft tube lights can be driven.

According to a preferred embodiment of the present invention the DC/Solar power operated LED tube lights are having the specification as given in following Table I:

It is thus possible by way of the present invention to providing a DC(Battery)/Solar operated LED tube light of suitable length, such as 2ft or 2.5 ft, and also of various sizes and configurations for various applications for home or office or decorative lighting, particularly beneficial in rural areas where grid power supply may not be available, so as to provide illumination of desired brightness and covering wider area to replace use of conventional tube light with higher power rating. Such LED based tube lights shall be low power consuming, simple to install and ensure longer life with minimum maintenance. LED tube lights of the present invention would on one hand be eco-friendly cost effective energy efficient light sources free of pollution and on the other hand ensure lighting in areas where no grid power is available to thereby ensuring better living/ working conditions and thus having prospects of wide scale application in households as well as offices for a variety of purposes.

We Claim:

1. LED based lighting system comprising
an aluminium base supporting an assembly of LEDs on a PCB and adapted to serve as a heat sink, a cooperative LED driver electronics and an operating cable connecting to the DC power source.

2. LED based lighting system as claimed in claim 1 comprising a DC (Battery) / Solar operated 2ft LED tube light comprising of said aluminium extruded base, said LED assembly on a PCB, said LED driver electronics, end caps and said operating cable connecting to the power source selected from (i) DC power source (ii) a battery (iii) a solar panel through a charge control unit (CCU) and battery.

3. LED based lighting system as claimed in anyone of claims 1 or 2 wherein said aluminium extruded base acts as a support for placing PCB containing the LED assembly with suitable glue or adhesive.

4. LED based lighting system as claimed in anyone of claims 1 to 3 wherein a driver PCB provides necessary power to drive the LEDs with constant current sources to produce desired light output.

5. LED based lighting system as claimed in anyone of claims 1 to 4 wherein a PMMA diffuser or a PMMA clear transparent tube provides a casing for the assembly enabling the light output from the LEDs to be dispersed uniformly.

6. LED based lighting system as claimed in anyone of claims 1 to 5 wherein the number and type of LEDs is based on the light output needed for an application.

7. LED based lighting system as claimed in anyone of claims 1 to 6 wherein the length of the tube can be increased to 2.5ft to accommodate more LEDs for more power and light output.

8. LED based lighting system as claimed in anyone of claims 1 to 7 wherein a SPV panel and charge control electronics facilitate charging of the battery during the sunny hours to support the autonomy - the duration of lighting requirements during the non sunny hours.

9. LED based lighting system as claimed in anyone of claims 1 to 8 wherein a clear transparent tube is used in place of the diffuser for more light on the target areas.

10. LED based lighting system as claimed in anyone of claims 1 to 9 which is adaptable in various sizes and configurations for variety of applications extending from home or office lighting to emergency lighting to home lighting to the rural households.

11. LED based lighting system as claimed in anyone of claims 1 to 10 wherein the tube light can be used either with a DC source or a battery only or with a solar panel and battery.

12. LED based lighting system as claimed in anyone of claims 1 to 11 adapted such that the same can be fitted to the ceiling or wall preferably with a couple of clamps dispensing with the need for fixture, choke and starter.

13. LED based lighting system as claimed in anyone of claims 1 to 12 wherein two such tube lights are operated with one set of SPV / CCU / Battery combination in a typical rural, home lighting application.

14. LED based lighting system as claimed in anyone of claims 1 to 13 which is extendable and configurable as per the end application.

15. LED based lighting system substantially as hereindescribed and illustrated with reference to the accompanying figures.