Removable food support element in a refrigerator with means for setting the temperature of the compartment in which it is positioned, and a refrigerator containing such a compartment

Information

  • Patent Grant
  • 6698222
  • Patent Number
    6,698,222
  • Date Filed
    Friday, August 9, 2002
    22 years ago
  • Date Issued
    Tuesday, March 2, 2004
    20 years ago
Abstract
A removable food support element in a refrigerator, for example a shelf, drawer or the like, comprising a body to be positioned on supports present on opposing walls of a refrigerator compartment; there being provided, associated with the body of the element, setting means enabling the internal temperature of the refrigerator compartment to be set and the set temperature information to be transferred to control means for the refrigerator refrigeration circuit.The refrigerator provided with such a compartment is also claimed.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a food support element in a refrigerator, in accordance with the introduction to the main claim. The term “refrigerator” used herein means both refrigerated cabinets in which the temperature is normally higher than 0° C., and freezers in which the temperature is maintained below 0° C.




In a refrigerator (static or forced-air) it is very important to correctly determine the temperature of each of its preservation or freezer compartments in order to obtain optimum preservation of the foods contained therein.




2. Description of the Related Art




Various devices are known for enabling said determination, these devices generally measuring said temperature in correspondence with a wall of said compartment or in correspondence with a conduit through which air is fed into the compartment (in the case of a forced-air refrigerator), or indirectly by measuring the evaporator temperature. Although enabling functional monitoring of the temperature in the refrigerator compartment, these devices do not enable the actual temperature within the compartment to be measured or to be maintained at the desired optimum value within the compartment on the basis of the foods present therein. In this respect, this temperature is set by the user by operating an appropriate control associated with a structural part of the refrigerator (compartment wall or door, for example), this setting being maintained by measuring the obtained temperature using the aforesaid known devices, this measurement never however being taken directly at a point in the interior of said compartment, i.e. between its walls where the foods are present, with obvious drawbacks (for example measurement inaccuracies or the need for complex systems for processing the temperature information obtained for example in proximity to a wall in order to define the temperature present within the compartment).




SUMMARY OF THE INVENTION




An object of the present invention is therefore to provide a removable refrigerator element of the aforesaid type which enables a temperature to be set, or enables a class of foods to be set to which a determined temperature range corresponds, and which is to be obtained and possibly maintained within the refrigerator compartment or within a particular region thereof.




Another object is to provide an element which is reliable and easy to use.




A further object is to provide an element which, in a refrigerator or in a forced-air freezer, enables a particular temperature to be maintained within that particular region of the refrigerator compartment in which the element is positioned, on the basis of the type of food positioned on the element.




These and further objects which will be apparent to the expert of the art are attained by an element in accordance with the accompanying claims.











BRIEF DESCRIPTION OF THE DRAWINGS




The present invention will be more apparent from the accompanying drawing, which is provided by way of non-limiting example and in which:





FIG. 1

shows schematically one embodiment of a shelf according to the invention inserted into a refrigerator compartment;





FIG. 2

is a perspective front view of the shelf of

FIG. 1

; and





FIG. 3

is a schematic diagram of an electrical/electronic circuit enabling the temperature to be set within the interior of the compartment of

FIG. 1

in which several shelves according to the invention are present.











DESCRIPTION OF THE PREFERRED EMBODIMENT




With reference to said figures, a refrigerator is shown schematically in

FIG. 1

, where it is indicated by


1


. The refrigerator can be of the known static or forced-air type.




In the example. the refrigerator is an upright refrigerator and comprises an internal compartment


2


having opposing lateral walls


3


,


4


and an end wall or shoulder


5


. Usual supports (not shown) are present on the lateral walls to support a shelf


6


formed in accordance with the invention.




The shelf


6


comprises means


10


to enable the internal temperature of the compartment


2


to be set (or a temperature range corresponding to a determined food category to be set) and possibly to be maintained. These means


10


cooperate with the control means


11


controlling the operation of the refrigerator


1


, in order. to control and regulate, on the basis of the temperature setting obtained by the setting means, the operation of a usual refrigeration circuit schematically shown in FIG.


1


and indicated by


12


.




More specifically, the shelf


6


comprises a body


15


presenting lateral faces


16


and


17


to face the walls


3


and


4


of the compartment


2


, a front face


18


and a rear face


19


. The shelf


6


presents a flat surface


20


for supporting foods. According to the invention, the body


15


contains the setting means


10


associated with operating means


21


positioned preferably on the aforesaid front face


18


. These means for setting the internal temperature of the compartment


2


are an electrical and/or electronic circuit


22


suitably inserted into the body


15


, and can be of active type (i.e. self powered for example by batteries) or of passive type.




In the figures the circuit


22


is an electrical circuit of passive type defined by an RLC resonant circuit and comprising an inductor


23


positioned in correspondence with the lateral face


16


of the body


15


of the shelf


6


and a plurality of capacitors (for example three, as in the figures where they are indicated by


26


,


27


and


28


) of various capacitances. Each capacitor is connected on one side to an electrical line


30


connected to one end of the inductor


23


, and on the other side to a change-over switch (


31


,


32


and


33


respectively) arranged to connect each capacitor to a second electrical line


35


,


36


and


37


respectively, connected to an electrical branch


38


connected to the other end of the inductor


23


.




Using the operating means


21


, a different change-over switch can be activated to connect the corresponding capacitor to the inductor in such a manner as to modify the resonance frequency of the circuit


22


.




The operating means


21


can be defined by a plurality of pushbuttons P


1


, P


2


, P


3


and P


4


(

FIG. 2

) connected to the various capacitors and which, when pressed, result in the selection of a temperature suitable for preserving different foods. For this purpose, each pushbutton carries a symbol corresponding to a particular food. Alternatively, the operating means


21


can be defined by a slidable selector


39


movable along the face


18


of the body


15


of the shelf


6


, or by a slidable reed relay, in which case the selector


39


carries a magnet


40


which on sliding in front of the change-over switch defined by a relay, closes it onto the corresponding electrical line. This results in the selection of a particular capacitance for the circuit


22


and hence the selection of a particular resonance frequency. Hence a respective desired temperature within the compartment


2


can be made to correspond to each frequency variation of the circuit


22


, this temperature being selected for example via the selector


39


.




To enable the circuit


21


to operate, an inductor


41


is positioned in that wall


3


of the compartment


2


which faces the face


16


of the shelf body


15


, and is connected to an oscillating circuit


42


connected to the refrigerator control means


11


, for example a microprocessor circuit. On powering the oscillating circuit


42


, of which the inductor


41


forms part, the circuit


21


is activated, so that each variation in the resonance frequency of said circuit


21


(obtained in the aforesaid manner) is noted as a variation in the resonance of the circuit


42


; this is then determined by the control circuit or means


11


which, on the basis of the variation, act on the refrigeration circuit


12


.




Specific reference will now be made to

FIG. 3

showing a plurality of shelves


6


cooperating with an electrical/electronic circuit which determines their resonance frequency variation and on the basis thereof acts on the refrigeration circuit


12


. If the embodiment of

FIG. 3

is used in a forced-air refrigerator, a particular temperature on each shelf of the refrigerator compartment


2


can be obtained by adjusting in known manner the usual members for modifying the feed of refrigerated air into the various regions of the compartment


2


. In this case the shelves


6


are constructed of thermally insulating material.




The use of the invention will now be described with reference to FIG.


3


.




It will be assumed that the uppermost shelf


6


of

FIG. 3

is to be used. The other shelves will be assumed not to be in use or, if present in the compartment


2


, not to be used for setting a local temperature within the refrigerator compartment


2


.




As shown in

FIG. 3

, the control circuit


11


(for example a microprocessor) is connected to the control voltage generator or sweep generator


50


, connected to the oscillator


42


which operates with controlled voltage. This latter is connected to a switching element


53


which selects the appropriate inductor


41


for interrogating a determined shelf.




On powering the circuit


42


, of which the inductor


41


forms part, and varying the capacitance of the resonant circuit


21


, the resonance frequency of the oscillator undergoes, as stated, a variation which is determined by a usual signal sensor


55


(for example a dip catcher), and is therefore determined by the circuit


11


. On the basis of this determination, corresponding to the selection of a particular temperature within the compartment


2


, the circuit


21


acts on the refrigeration circuit


12


to obtain the desired temperature within the compartment


2


(in correspondence with the shelf


6


).




If several shelves


6


are present and “active” within the refrigerator, for example a forced-air refrigerator, any signal variations of the corresponding inductor


41


are discriminated by the control circuit


11


which, by directly operating the switching element, is always able to recognize which inductor has been the origin of the signal generated by the oscillator


42


. On the basis of this determination, the circuit


11


can vary the temperature of that portion of the compartment


2


comprising the shelf


6


in question.




In a further embodiment of the invention, any deviation in the actual temperature from that set for each shelf


6


of the invention can be determined directly by the circuit


11


, as this temperature variation results in a proportional variation in the capacitance of the capacitor selected by the circuit


21


and hence a variation in the resonance frequency of said circuit (determined by the control circuit


11


). This circuit acts on the refrigeration circuit


12


on the basis of this determination.




Two embodiments of the invention have been described. Others can however be devised in the light of the present invention. For example, as stated, the circuit


22


can be of active type and comprise remote connection means (for example of radio-frequency, or other type) able to dialogue with the control means


11


in order to “inform” these latter of the temperature selected by the user for the shelf


6


. Alternatively, the circuit


22


can be of the described type, but self-powered and cooperating with a device (passive, of inductor type) connected to the means


11


and not comprising the oscillator


42


, the generator


50


or the sensor


55


. Moreover, although the described examples refer to a shelf, the circuit


22


can also be provided on a food containing drawer (for example, as in the case of upright freezers).



Claims
  • 1. A removable food support element in a refrigerator, for example a shelf or drawer, comprising a body to be positioned on supports present on opposing walls of a refrigerator compartment, and, associated with the body of the element, setting means enabling an internal temperature of the refrigerator compartment to be set and the set temperature information to be transferred to a control means for a refrigerator refrigeration circuit, the setting means comprising a resonant circuit arranged to generate a signal which can be modified on the basis of the set temperature, or of a set temperature range, by modifying at least one electrical characteristic of the circuit, the resonant circuit comprising a plurality of capacitors of different capacitances selectively connectable to an inductor cooperating with an induction element associated with the control means and fixed to the refrigerator.
  • 2. An element as claimed in claim 1, wherein the resonant circuit is of passive type, the induction element being connected to an oscillating circuit connected to the control means, and receiving an electrical signal from said circuit.
  • 3. An element as claimed in claim 1, wherein the resonance circuit is self-powered.
  • 4. An element as claimed in claim 1, comprising operating means operationally cooperating with the resonant circuit to select a capacitor of capacitance chosen on the basis of the desired temperature or of the desired temperature range in correspondence with the element.
  • 5. An element as claimed in claim 4, wherein the operating means are a selector movable on a face, preferably the front face, of the element.
  • 6. An element as claimed in claim 4, wherein the operating means are a plurality of pushbuttons operationally connected to the various capacitors.
  • 7. An element as claimed in claim 4, wherein the operating means act on switches arranged to connect different capacitors to the inductor.
  • 8. An element as claimed in claim 1, wherein the electrical circuit comprises radio-frequency signal generating means cooperating with receiving counter-means connected to the control means.
  • 9. A removable food support element in a refrigerator, for example a shelf or drawer, comprising a body to be positioned on supports present on opposing walls of a refrigerator compartment, and, associated with the body of the element, means for measuring the temperature present in the refrigerator compartment, setting means comprising a resonant circuit and configured to enable an internal temperature of the refrigerator compartment to be set and the set temperature information to be transferred to a control means for a refrigerator circuit, the measurement means comprising capacitors of the resonant circuit.
Priority Claims (1)
Number Date Country Kind
MI2001A1798 Aug 2001 IT
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Number Name Date Kind
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6584786 Tavolazzi Jul 2003 B2
20020184906 Faries, Jr. Dec 2002 A1
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Number Date Country
3604759 Aug 1987 DE
19505830 Aug 1995 DE
9417655 Feb 1996 DE