FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
The Patent Rules, 2003
Provisional Specification
(See section 10 and rule 13)
NOVEL DEVICE AND METHOD OF ILLUMINATION IN REFRIGERATORS.
Whirlpool of India Limited.
A-4 MIDC Ranjangaon, Taluka Shirpur, Pune 419204, Maharashtra State, India
An Indian company registered under the Companies Act, 1956
The following specification describes the invention:

NOVEL DEVICE AND METHOD OF ILLUMINATION IN REFRIGERATORS
FIELD OF INVENTION
The present invention relates to the field of illumination in refrigerators and
particularly to a novel device and method of illumination.
BACKGROUND OF INVENTION
In Customer feedback process it is significantly pointed out that the Customer is
discomforted because of failure of bulb which bulb is most essential to illuminate the objects stored inside the refrigerator. If the bulb does not fuse early, it's good, otherwise it adds to discomfort as the replacement of the bulb usually gets neglected for a length of time at home, and therefore illumination is not available to locate the stored items in the refrigerator.
There are chances of bulb failures during transfer or handling of refrigerator during delivery and transportation from one place to other.
While opening the door of refrigerator, force applied while opening the door leads to vibration of bulb filament, whereas the door switch simultaneously activates the power supply and provides supply of electrical power to the bulb. This develops stress on the filament of the bulb and hence is observed to be one of the failure modes of bulb.
2

The voltage fluctuations in the mains incoming electrical power supply leads to failure of bulb due to fusing of filament.
Manufacturers of the bulbs usually specify the life of bulb to be 2,000 hours of continuous illumination, which would reduce further if the application is an intermittent on / off type as in refrigerators.
While loading the refrigerator with food items during regular day-to-day use, there are chances of hitting the bulb, leading to cracking of glass enclosure of bulb.
Bulb and bulb holder assembly are located in the refrigerator such that they occupy the usable space in the refrigerator.
As the bulb and bulb holder needs to be assembled with a definite torque and this construction mode itself can lead to the breakage of glass envelope during assembly or bulb changing operation taking place at the customer end.
The overall mechanical assembly of the holder and the bulb contact being spring loaded leads to electrical failure of bulb in operation and also during transportation, usage and handling.
During power cut and/or shut down condition the refrigerator loses its electric supply so that there is no illumination inside the refrigerator. Hence it becomes difficult to locate things stored inside the refrigerator.
3

Bulbs consume 15W of electric power and also leads to heat generation inside the refrigerator when illuminated for a long time.
Location of the bulb in the refrigerator is such that there is not a uniform distribution of light inside the refrigerator.
The light intensity of bulb is uncomfortable to the bare eye.
To make the bulb compartment safe from electrical shock and also fire proof as the temperature is more, it incurs more design and manufacture cost for the enclosure to be of fire retardant grade .
The yellow light in freezer and refrigerator compartments looks very traditional and is also very disturbing to the eyes. Light source is concentrated on one side of the refrigerator compartment (RC) and freezer compartment (FC) and leads to non uniform illumination in the refrigerator.
With changing trends of market, customer needs a refrigerator which is not traditional in design and has differentiation factor. Also it should be robust and have a low service incidence rate.
Hence there is a perceived need for providing a novel device and method of illumination for a refrigerator, which will overcome the disadvantage of present illumination system for a refrigerator.
4

OBJECTS & ADVANTAGES OF PRESENT INVENTION
Accordingly the objects and advantages of present invention are described below.
An object of invention is to reduce the customer discomfort occurring due to failure of bulb.
Another object of invention is to reduce chances of bulb failures during transfer or handling of refrigerator during delivery and transportation.
Yet another object of invention is to reduce chances of failure of bulb while opening the door of refrigerator,
Further object of invention is to reduce chances of failure due to voltage fluctuations in the electrical power supply.
Still further object of invention is to increase the life of source of illumination in the refrigerator to much more than 2000 hours.
Yet further object of invention is to reduce chances of failure while loading the refrigerator by reducing chances of hitting the bulb leading to cracking of glass -enclosure of bulb.
Another object of invention is to increase the usable space in the refrigerator.
Yet another object of invention is to reduce chances of failure while assembling bulb and bulb holder.
5

Still another object of invention is to reduce chances of failure due to mechanical assembly of the holder and spring loaded bulb contacts, thereby reducing chances of failure of bulb during transportation, usage and handling of refrigerator.
Further object of invention is to reduce chances of discomfort to customer during power cut and/or shut down condition when the refrigerator loses its supply, so that there is no illumination inside the refrigerator also, thereby making it difficult to locate things inside the refrigerator.
Still further object of invention is to reduce power consumption from 15W to less than 2W of power.
Yet further object of invention is to provide uniform distribution of light in refrigerator and freezer compartments, (RC and FC).
Another object of invention is to provide illumination which will be more comfortable to bare eye.
Yet another object of invention is to reduce design and manufacturing cost of bulb enclosure.
Still another object of invention is to provide suitable light in freezer compartment (FC) and refrigerator compartment (RC) with different color scheme than normal yellow light and the assembly unit being located at a suitable location so that light
6

can be uniformly distributed in the freezer compartment (FC) and the refrigerator compartment (RC).
Further object of invention is to provide a refrigerator with a non traditional design and which has differentiation factor, which is also robust and having a low service incidence rate.
Still further object of invention is to provide the consumer with longer life of illumination source with different improved aesthetic styles.
Another object of invention is to provide an illumination device and system which is always available for use all the time.
Yet another object of the invention is to provide a novel method of illumination in refrigerator and freezer compartments
BRIEF DESCRIPTION OF DRAWINGS
FIGURE 1 - shows board housing which' goes into the liner in the prefoam assembly and gets fixed up after foaming as the liquid takes up the shape of the profile.
FIGURE 2 - shows transparent light-dispersing member which holds the PCB and together gets snap fitted onto the board housing.
FIGURE 3- shows light - emitting diode (LED) with printed circuit board, which
board has the mounting of electronic components as shown in the figure. 4
7

FIGURE 4 - shows the schematic diagram of the circuit used for illumination.
NOMENCLATURE OF PARTS USED IN THE INVENTION
Number of Part Nomenclature of Part
(1) Printed Circuit Board (PCB)
(2) Light Emitting Diodes (LED)
(3) PCB Bracket
(4) Transparent light dispersing member
(5) Direct Current (DC) Power Supply
DESCRIPTION OF INVENTION
In the present invention is provided a novel device and method for illumination in
the refrigerators. The parts and construction of the novel device are explained with respect to the Figure numbers 1 to 4.
In the most preferred embodiment of the present invention, novel device comprises of:
1) Printed Circuit Board (PCB).
2) Plurality of Light Emitting Diodes (LED).
3) PCB Bracket.
4) Transparent light dispersing member.
5) Direct Current (DC) Power Supply.
8

Initially the PCB Bracket (3) is mounted in the liner of refrigerator compartment (RC) during the prefoaming assembly on the refrigerator manufacturing line and gets fixed up after foaming is done, as it forms the shape of the bracket from inside and after curing it behaves as an integral structure thus fixedly holding the PCB bracket (3).
The transparent light dispersing member (4) and printed circuit board (PCB) (1) are assembled outside by sliding the PCB (1) on the bracket guide.
The PCB (1) and bracket are assembled by connecting the connector of wiring to the PCB connector and snapping the whole transparent light dispersing member onto the bracket.
The LED - PCB receives the power supply from a DC source located in the compressor compartment, and which source is preferably ranging from about 5V to about 20V, and more preferably ranging from about 10V to about 20V.
After the door of refrigerator is opened, the door switch gets activated and provides electric supply to the LED-PCB which in turn illuminates the interior with uniform diffused light, after the light passes through the transparent light dispersing member.
This diffused light will comprise of suitable combination of different colours of light as per the preference of the customer. This combination will be preferably a
9

combination of whites & blues in case of white colour of refrigerator's interior or suitable colour as per the background colour and requirement of the customer.
In one embodiment of this invention is provided additionally a back up arrangement of a battery of pencil cells, for power supply to the circuit of LED, as it is operating on a DC source of voltage from 5V and above, which lies in the standard range of commercial pencil cells. The provision of this back up arrangement gives a special advantage in the present invention as compared to the existing refrigerators having filament - light - bulb arrangement. Due to this back up arrangement provided in the present invention, illumination inside the refrigerator is available all the time. In existing refrigerators with usual bulb arrangement, illumination is absent inside and outside the refrigerator when there is power cut or shut down condition, thereby making it very difficult to locate things stored in the refrigerator due to absence of illumination in such cases. As described above, this problem is absent in the present invention wherein the backup arrangement, which comes into play when power cut or shut down condition comes into existence.
A special feature of construction used in the present invention, as shown in Fig. 4, is that the circuit provides a combination of plurality of LEDs which are arranged in parallel. The special advantage of this parallel arrangement is that, even if one LED-line fails, other balance LED-lines from the plurality of LEDs, are available to provide illumination for the inside space of the refrigerator.
10

One special feature of construction of the present invention is that the novel device of this invention is fixed to the roof area of the inside space of refrigerator compartment and other similar novel device in freezer compartment is fixed similarly. This location of fixing the novel illuminating device makes available more usable space inside refrigerator compartment (RC) and freezer compartment (FC).
As only LEDs are used in the present invention, instead of using usual filament-light-bulb, the lighting unit in the RC as well as in FC will have life of 10 to 15 years in contrast with 2000 hours life of filament-light-bulb.
As the novel illumination device of the present invention operates on low voltage DC source, the device reduces chances of failure due to common voltage fluctuations occurring in the electrical power supply.
As the present invention does not use any wire-filament, the chances of discomfort to customers due to the risk of failure of bulb due to fusing of filament is absent.
The reliability of this novel lighting device using LEDs reduces the chances of occurrence of discomfort to the customer as is happening currently in case of failure of light bulbs in the existing refrigerators.
11

Unlike the non-uniform illumination in the RC and FC compartments due to near-point-light-source like a filament-bulb in existing refrigerators, the present invention provides a uniform illumination in RC and FC compartments.
Due to use of LEDs in the novel device of present invention, there is no chance of failure of illumination unit during transfer or handling of refrigerator during delivery and transportation.
Due to location of illumination unit near roof area of FC and RC compartments, the risk of hitting the lighting unit while loading the refrigerator is absent.
There is less power consumption by the illumination device used in the present invention, as it uses low voltage DC source of power supply.
Dated this 30th Day of March, 2006

(Mr. Tase, Sharatchandra Dattatraya) Applicant's patent agent Registration Number IN/PA 879
To,
The Controller of Patents,
Patents Office Branch, Mumbai
Plot No. 352, Baudhik Sampada Bhavan,
Near Antop Hill Post Office, SM Road,
Mumbai 400 037
12