The present invention is related to providing heating by means of an illuminating lamp, that can be controlled with a serial switch or using a button with two contacts as the button providing the internal illumination according to the position of the door and connecting a diode to one of the said contacts, in a two-door refrigerator having a freezer and a fresh food compartment.
During normal operation of the refrigerator, the compressor is stopped when the inner temperature of the fresh food compartment reaches the required level, as detected by the thermostat; and when the fresh food compartment temperature reaches a certain level, the thermostat changes its position in order to switch in the compressor. This rise in the temperature of the fresh food compartment can occur naturally or additional electrical heaters can be used to accelerate the warming up. The said heaters, also prevent the frost formation etc. due to the condensation in their area.
In the conventional techniques, the lamp is used as the heater and its power is reduced by means of resistive elements so that it can be used both for illuminating and for heating purposes. In the Patent Application No: WO98/49507, the lamp used for both illuminating and heating purposes, by reducing its value using a capacitor, is disclosed. The capacity of the lamp can be modified depending on the value of the capacitor.
The object of the present invention is to use the lamp also as a heater when required, without consuming much energy.
Power reduction by diode in the refrigerators wherein the lamp is used also as a heater, that is realized in order to attain the above mentioned object of the present invention, is illustrated in the attached drawings, wherein:
The components shown in the drawings have been individually enumerated as follows:
In order to enable a two-door refrigerator with freezer and fresh food compartments to operate under low ambient air temperature the lamp (2) in the fresh food compartment is used as a heater when the door is closed, this prevents the inner temperature of the said compartment from falling below a determined level and enables the normal operation of the compressor (6). In this case the lamp (2) functions as an illuminator and a heater.
On one of the two branches connected in parallel to each other, there is a diode (1) connected in series to the heater position switch (4) and on the other branch there is only one illumination position switch (5). This circuit is connected in series to the lamp (2) and is located before the lamp (2). The lamp (2) is used for heating purpose when the refrigerator door is closed and the heater position switch (4) is on. For this purpose, a single contact switch which is normally off, is used as the illumination position switch (5). The position of the contact changes depending on the position of the door. There exists a heater position switch (4) connected in series to the lamp, in order to enable the user to use the lamp (2) as the heater. In case when the lamp (2) is used for heating purposes, if the heat generated by the lamp (2) is higher than that is required, the lamp current, therefore the lamp power, can be reduced to its half value and energy can be saved, by means of a diode (1) connected in series to the heater position switch (4) and to the current path. When the refrigerator door is opened and the switch (5) comes to illumination position, an illumination that is proportional with the nominal power of the lamp can be obtained without any loss in its illuminating efficiency. Furthermore, by preventing the lamp from being illuminated when heating is not needed, by means of the switch (4) connected in series, unnecessary energy consumption is avoided (Figure 1).
In another embodiment, where the lamp (2) is used as a heater, the diode (1) is connected in series to the normal "off" contact of a door button switch (7) with two contacts (7a, 7b). In this case, the lamp (2) stays illuminated and provides a heating with the desired capacity, when the refrigerator door is closed. When heating is not needed, the lamp (2) is prevented from being continuously illuminated, by using the heater position switch (4) connected in series and thus unnecessary energy consumption is avoided. In the "on" position of the said heater position switch (4) connected in series, the lamp (2) will be kept illuminated in low capacity status no matter if the door is open or closed. In this manner heating will be realized and the refrigerator will be able to operate in normal cycle. When the heater position switch (4) is at "off' position, the refrigerator illumination lamp will carry on its normal function (Figure 2).