[006]The disclosure provides an automatic-defrost voltage stabilizer for automatically defrosting a refrigerator connected to said voltage stabilizer. Further, the present disclosure, in certain embodiment may also provides an automatic-defrost voltage stabilizer for automatically defrosting a refrigerator and at the same time providing a regulated voltage supply to the refrigerator.[007]In oneembodiment, an automatic defrost voltage stabilizer for use in refrigeratorsis disclosed. The disclosed stabilizercomprisesa controller (101) configured to initiate a timer on detection of active condition of the defrost voltage stabilizer,a relay circuit (105) configured to receive a first signal from the controller (101). In one aspectthe first signal indicates, based on the timer, that a first predetermined time from the activation of the defrost voltage stabilizer is elapsed. Furtherthe relay circuit (105), configured to turn off power supply to a refrigeratorin response to receipt of the first signal.[008]In another embodiment, the stabilizer disclosed herein comprises the controller (101) configured to reset the timer on detection of off condition of power supply,the relay circuit (105) configured to receive a second signal from the controller (101). In an aspect,the second signal indicates, based on the timer, that a second predetermined time from power off condition of the refrigerator is elapsed.The disclosed stabilizer further comprises the relay circuit (105), configured to turn on power supply to the refrigerator in response to the second signal.[009]In another embodiment, the stabilizer disclosed herein comprises the controller (101) configured to reset the timer on detection of off condition of power supply,the relay circuit (105) configured to receivea second signal from the controller (101). In an aspect,the second signal indicates, based on the timer, that a second predetermined time from power off condition of the refrigerator is elapsed.The disclosed stabilizer further comprises the relay circuit (105), configured to turn on power supply to the refrigerator in response to the second signal. [0010]In yet another embodiment the disclosed stabilizer comprises an energy storage element (113), wherein when the utility mains power is not available or is turned off between the
powering on of the auto-defrost voltage stabilizer and the first predetermined time the controller is powered using the stored power in the energy storage element (113). Further, If the duration of non-availability of the utility mains power is greater than a third predetermined time, then the energy storage element is depleted. Thereby, powering off and resetting the controller(101). In other words, the controller is reset if the duration of non-availability of the utility mains power is greater than a third predetermined time.[0011]In another embodiment, the present disclosure provides a method forautomatic defrost in refrigerators using an automatic defrost voltage stabilizer. In an embodiment the disclosed method comprises the steps of initializing, by a controller (101), a timer on detection of active condition of the defrost voltage stabilizer. The method further comprises receiving, by a relay circuit (105) a first signal from the controller (101). In an aspectthe first signal indicates, based on the timer, that a first predetermined time from the activation of the defrost voltage stabilizer is elapsed. Further, the disclosed method comprises turning off, by a relay circuit (105), power supply to a refrigerator, in response to receipt of the first signal. [0012]In another embodimentthe presently disclosed method mayfurthercomprise resetting, by the controller (101), the timer on detecting off condition of power supply,receiving, by the relay circuit (105), a second signal from the controller (101). In an aspectthe second signal indicates, based on the timer, that a second predetermined time from power off condition of the refrigerator is elapsed. The method may further comprise,turning on, by the relay circuit (105), power supply to the refrigerator in response to the second signal.BRIEF DESCRIPTION OF THE DRAWINGS [0013]The foregoing summary, as well as the following detailed description of preferred embodiments, are better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings exemplary constructions of the invention; however, the invention is not limited to the specific methods and system/ devicesdisclosed. In the drawings:
[0014]Figure 1:illustrates a block diagram of the auto-defrost voltage stabilizer, according to one embodiment of the present disclosure;[0015]Figure 2: illustrates the method of working of the auto-defrost voltage stabilizeraccording to one embodiment of the present disclosure; [0016]Figure3:shows a schematic diagram of the auto-defrost stabilizer circuit,according to one embodiment of the present invention;[0017]Fig 3A: shows a part of the schematic diagram of FIG. 3 showing the controller and itsassociated components,according to oneembodiment of the present invention;[0018]FIG. 3B shows a part of the schematic diagram of FIG. 3 showing the power supply circuit and the energy storage element, according to one embodiment of the present invention; [0019]FIG. 3C shows a part of the schematic diagram of FIG. 3 showing the input/output voltage sensing circuit, according to one embodiment of the present invention; and[0020]FIG. 3D shows a part of the schematic diagram of FIG. 3 showing the relay circuitry, according to one embodiment of the present invention.DETAILED DESCRIPTION OF THE INVENTION[0021]Some embodiments of this invention, illustrating all its features, will now be discussed in detail. [0022]The words "comprising," "having," "containing," and "including," and other forms thereof, are intended tobe equivalent in meaning and be open ended in that an item or items
following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items.[0023]It must also be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, the preferred, systems and methods are now described. [0024]The disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms.[0025]The elements illustrated in the figures inter-operate as explained in more detail below. Before setting forth the detailed explanation, however, it is noted that all of the discussion below, regardless of the particular implementation being described, is exemplary in nature, rather than limiting.[0026]The present invention is directed to an automatic-defrost voltage stabilizer for automatically defrosting a refrigerator connected to said voltage stabilizer and at the same time providing a regulated voltage supply to the refrigerator. The automatic-defrost voltage stabilizer comprises a controller (101), an energy storage element (113), a power supply circuit (103), an input/output voltage sensing circuit (109), relay circuit (105), a multi-tap transformer (107) and a display circuit (111).[0027]In accordance with the present disclosure the controller (101) receives power from the power supply circuit when the utility mains power is available and the controller (101) receives power from the energy storage element (113) when utility mains power is not available. The controller is coupled to the input/output voltage sensing circuit (109) to sense the input and output voltage and based on the sensed input and output voltage sends a signal to the relay circuitry (105) to provide regulated voltage supply to therefrigerator. The relay circuit based on
the signal received from the controller selects a tapping from the multi-tap transformer to output an optimum regulated voltage to the refrigerator. Further, the multi-tap transformer supplies power to the power supply circuit. The controller is further coupled to the display circuit (111) to display the current auto-defrosting status.[0028]Referring now to Fig 1 a block diagram of the auto-defrost voltage stabilizeris shown. The automatic-defrost voltage stabilizer comprises a controller (101), an energy storage element (113), a power supply circuit (103), an input/output voltage sensing circuit (109), relay circuit (105), a multi-tap transformer (107) and a display circuit (111).[0029]The controller (101) receives power from the power supply circuit when the utility mains power is available and the controller (101) receives power from the energy storage element (113) when utility mains power is not available. The controller is coupled to the input/output voltage sensingcircuit (109) to sense the input and output voltage and based on the sensed input and output voltage,sends a signal to the relay circuitry (105) to provide regulated voltage supply to the refrigerator. The relay circuit based on the signal received from the controller selects a tapping from the multi-tap transformer to output an optimum regulated voltage to the refrigerator. Further, the multi-tap transformer supplies power to the power supply circuit. The controller is further coupled to the display circuit (111) to display the current auto-defrosting status.[0030]FIG. 2 illustrates the method of working of the auto-defrost voltage stabilizer. The output of the auto-defrost voltage stabilizer is coupled to a refrigerator. The auto-defrost stabilizer thus turns off the output of the stabilizer,to turn off the refrigerator after first predetermined timeintervals.For example,after every 70hoursand 30 minutesof running of the refrigerator the refrigerator is turned off by the auto-defrost stabilizer for asecondpredeterminedtimeinterval e.g. 90 minutes.Further, it may be noted that these time intervals may adjustable. In an embodiment theseabove mentioned first and secondtime intervals may be adjustableat the time of production of the stabilizerin afactory. Further, during the turning off of the refrigerator for saidsecondpredetermined time interval melts the frost into water and the water is drained off,
thereby, defrosting the refrigerator.In an embodiment,the second predetermined time may be configurable. For example,a user of refrigerator/ stabilizer, using a user interface, may set the second predetermined time.Auser in a warm location/ season may set a low second predetermined time, whereas a user in a cold location/ season may set a longersecond predetermined time.Further, in another embodiment a user may be provided options to select the second predetermined time using a user interface coupled to the stabilizer.[0031]In case there is a power failure during the said regular interval, and if the duration of the power failure is greater than athirdpredetermined timee.g. for 90 minutesthen the auto-defrost stabilizer gets reset and upon restoration of power starts monitoring the runtime of the refrigerator afresh. In other words, in case of a power failure of a predetermined amount of time, the auto-defrost stabilizer skips the originally scheduled turning off of the refrigerator, since the refrigerator has already been defrosted naturally during the power failure.[0032]In an embodiment, theauto-defrost stabilizer starts a timer initially when powered on and the timer starts counting the time for which the refrigerator has been running. Once the timer reaches 70hoursand 30 minutes, the refrigerator is turned off for 90 minutesfor allowingthe refrigerator to naturally defrost. Then the refrigerator is turned back on for normal operation for the next 70hoursand 30 minutes. However, if there is a power failure which lasts for 90minutes or more, within 72 hours(i.e. the 70 hours 30 minutes plus 90 minutes), then the auto-defrost stabilizer gets reset. Further,when the power to the auto-defrost stabilizer is restored, the auto-defrost stabilizer restarts the timer and starts counting from “zero” again. Hence, the auto-defrost stabilizer does not carry out the scheduled turning off of the refrigerator as the refrigerator must have already been defrosted during the power failure.[0033]The auto-defrost stabilizer performs the above functions by initializing a timer, by the controller (101) and turning “ON” the output power of the auto-defrost stabilizer by sending a signal to the relay circuit (105) by the controller (101). In case there is no power failure, the controller (101) determines the time elapsed since the turning “ON” of the output powerof the auto-defrost stabilizer. If the controller (101) determines that a first predetermined time has
elapsed, the controller (101) sends a signal to the relay circuit (105) to turn “OFF” the output power of the auto-defrost stabilizer. Hence, the refrigerator turns off and starts to defrost naturally. The controller (101) then determines if a second predetermined time has elapsed from the time of turning “OFF” the output power of the auto-defrost stabilizer. Once the controller (101) detects that the second predetermined time has elapsed, the controller (101) turns “ON” the output power of the auto-defrost stabilizer. [0034]In case when a power failure occurs during the first predetermined time. The controller (101) continues to operate as it receives therequired power from the energy storage element (113). The energy storage element can only power the controller for a third predetermined amount of time and the energy storage begins to discharge on occurrence of said power failure. Hence, if the power failure extends beyond the third predetermined time, then the energy storage element gets depleted thereby turning off the controller (101). Once, the power supply is restored, the controller (101) is turned back on again the controller (101) resets the timeri.e. reinitializes the timer. Therefore, the process starts again as mentioned from paragraph [033]above. Further, when the power is restored, the energy storage element is replenished (charged) to its capacity.[0035]However, when the duration of the power failure is less than the third predetermined time, the energy storage element is not completely depleted, hence the controller (101) does not get turned off. In other words, in this case, the power supply is restored before the energy storageelement gets depleted and hence the controller (101) keeps on running uninterrupted. Accordingly, the scheduled defrosting cycle continues. The controller further signals the defrosting status of the auto-defrost stabilizer to the display circuit (111) for displaying the status of the current defrost operation.[0036]In an embodiment, the controller (101) monitors the input and output voltages of the auto-defrost stabilizer and signals the relay circuit (105) to select a tapping from the multi-tap transformer (107) to producean optimum output voltage to the refrigerator.
[0037]Referring now to Fig 3, a schematic diagram of circuit of voltage stabilizer as disclosed herein, is shown. Further Fig 3A, 3B, 3C and 3D illustrate specific circuits of the disclosed voltage stabilizer. Forexample, Fig 3A shows the controller and itsassociated components,according to one embodiment of the present invention. Fig 3B shows the power supply circuit and the energy storage element, according to one embodiment of the present invention. Fig 3C shows the input/output voltage sensing circuit, according to one embodiment of the present inventionand Fig 3D showsa part of the schematic diagram of FIG. 3 showing the relay circuitry, according to one embodiment of the present invention[0038]The disclosed invention is thus attained in an economical, practical, and facile manner. It is to be understood that various further modifications and additional configurations will be apparent to those skilled in the art. It is intended that the specific embodiments, configurations and calculations herein disclosed are illustrative and should not be interpreted as limitations on the scope of the invention

WE CLAIM:
1. An automatic defrost voltage stabilizerfor use in refrigerators, comprising:a controller (101) configuredto initiate a timer on activation of the defrost voltage stabilizer;a relay circuit (105) configured to receive a first signal from the controller (101),wherein the first signal indicates,based on the timer, that a first predetermined time fromthe activation of the defrost voltage stabilizer is elapsed;the relay circuit(105) configured toturn off power supply to a refrigeratorin response to receipt of the first signal.2. The automatic defrost stabilizer as claimed in claim 1, wherein:the controller (101)is configured to resetthetimer on detection of offcondition of power supply; the relay circuit (105) configured to receive asecond signal from the controller (101), wherein the second signal indicates, based on the timer, that a second predetermined time from power off condition of the refrigerator is elapsed;the relay circuit (105), configured to turn on power supply to the refrigeratorin response to the second signal.3. The automatic defrost stabilizer as claimed in any one of claim 1 or claim 2, further comprising an energy storage element (113) wherein the controller (101) is powered using the energy storage element during unavailability ofautility power supply. 4. The automatic defrost stabilizer as claimed in claim 3,wherein the energy storage element (113) powers the controller (101) for a third predetermined time and wherein the controller (101) is powered off after the third predetermined time period.5. The automatic defrost stabilizer as claimed in claim 4, wherein the power stored in the energy storage element (113) depletes once the third predetermined time period elapses.
6. The automatic defrost stabilizer as claimed in claim 4, wherein the controller (101) is powered on once the utility power supply is restored and wherein the timer is reset once the controller (113) is powered on.7. The automatic defrost stabilizer as claimed in claim 5, wherein power of theenergy storage element (113) is recharged by the utility power supply.8. The automatic defrost stabilizer as claimed in claim 1 further comprising a display circuit (111) configured to display a current auto-defrost status. 9. A method for automatic defrost in refrigerators using an automatic defrost voltage stabilizer, themethod comprising:initializing, by a controller (101),a timer on activationof the defrost voltage stabilizer;receiving, by a relay circuit (105)a first signalfrom the controller (101), wherein the first signal indicates, based on the timer, that a first predetermined time from the activation of the defrost voltage stabilizer is elapsed;turning off,by a relay circuit (105),power supply to a refrigerator, in response to receipt of the first signal.10. The method as claimed in claim 9, further comprising:resetting, by the controller (101),the timer on detectingoff condition of power supply; receiving, by the relay circuit (105),a second signalfrom the controller (101), wherein the second signal indicates, based on the timer, that a second predetermined timefrom power off condition of the refrigerator is elapsed;turning on, by the relay circuit (105), power supply to the refrigeratorin response to the second signal.11. The method as claimed in any one of claim 9or claim 10, wherein the controller (101) is powered using aenergy storage element(113)during unavailability of a utility power supply.
12. The method as claimed in claim 11, wherein the power stored in the energy storage element (113) depletes once the third predetermined time period elapses. 13. The method as claimed in claim 12, wherein the energy storage element (113) powers the controller (101) for a third predetermined time and wherein the controller (101) is powered off after the third predetermined time period. 14. The method as claimed in claim 13, wherein the controller (101) is powered on, once the utility power supply is restored and wherein the timer is reset once the controller (113) is powered on. 15. The method as claimed in claim 12, wherein power of the energy storage element (113) is recharged by the utility power supply once the utility power supply is activated.