AU602984B2 - Absorption-diffusion refrigerator - Google Patents

Description

i^i" COMMONWEALTH OF AUSTRALIA Patent Act 1952 COMPLETE SPECIF

(ORIGINAL)

ICATIO 0 N o602984 Class CInt. Class Application Number Lodged Complete Specification Lodged Accepted This locm-cen-tannis l I7h~is mn Contains the -#lm)dmerits mae uuclje I'-tiojn 49 and is correct 1 oj i rg...

Published Priority :18 May 1987 Related Art Name of Applicant Address of Applicant Actual Inventor/s Address for Service :ASSOCIATION POUR LA RECHERCHE ET LE DEVELOPPEMENT DES METHODES ET PROCESSUS INDUSTRIELS-

A.R.M.I.N.E.S

60, Boulevard Saint-Micael 75272 Paris, Cedex 06. France Denis CLODIC Robert DEHAUSSE F.B. RICE CO., Patent Attorneys, 28A Montague Street, BALMAIN 2041.

Complete Specification for the invention entitled: ABSORPTION-DIFFUSION REFRIGERATOR The following statement is a full description of this invention including the best method of performing it known to us/m:refrigerant, generally ammoniaca, and it comprises a refrigerating unit hing, at the outside and a t the rear of diffusion refrigerator comprising a lower refrigboiler connected by a tube to condenser situated in upper freezing compart of the refrierator and externally thereof The output of this condtype uses ther is cycle of acted 1 to a n evaporator comprisingally aoniaa, antube disposed it wampis of the frefrigerating comparunit having, and in which the low the rear of the refrigerator, a lower boiler connected by a tube to e condenser situated in the upper part of the refrigerator and externally thereof. The output of this condenser is connected to an evaporator comprising a tube disposed in i; wall of the freezing compartment and in which the low temperature refrigerant flows. This upper part of the evaporator is connected to a lower part formed by a tube housed in the wall of the lower refrigeration compartment and in which the refrigerant flows at a higher temperature. The lower part of the evaporator is connected in its turn to an absorber situated at the rear of the apparatus and externally and which is itself connected to a reservoir connected to the boiler.

Some absorption-diffusion refrigerators known up to now one embodiment of which is described in the french patent FR-A- 1 251 816, are formed of an assembly of two parts which can be fitted one in the other, namely a parallelepipedic cabinet having an upper horizontal cross member separating the freezing compartment, open on its rear face, from the refrigeration compartment, and, an assembly which may be fitted sealingly into the cabinet, L..is assembly comprising the refrigerating unit and a vertical plate made from a heat insulating material, fitted over an opening formed in the rear face of the cabinet,for closing this opening. This rear plate is extended forwards, at its upper part, by a box engaged in the volume Bfined between the upper horizontal wall,'the horizontal cross _1_CI~ _Il- i i 2 member and the vertical walls of the cabinet. In such a refrigerator the heat insulation between the upper freezing compartment of the cabinet and the box of the assembly engaged in this compartment requires two insulating materials of different types namely a rigid insulating material such as a foam forming the walls of the freezing compartment of the cabinet and a tearable braided fabrics, made for example from glass wool, which is interposed between the corresponding insulating walls of the cabinet and the box forming part of the assembly and which is fitted unequipped into the compartment of the cabinet. The upper freezing compartment of the cabinet plays in a way the role of an insulating mold core for injecting in situ the polyurethane foam, for example, forming the insulating wall.

The present invention relates to improvements made to this type of refrigerator so as to simplify the manufacture thereof and to obtain a perfect insulation between the two parts without having to use an intermediate tearable insulating layer of the glass fiber mat type.

comprising a lower refrigeration compartment, an upper fr fing compartment and an absorption-diffusion refrigera t g unit the assembly being made from two parts which n be fitted one into the other, namely a parallepipedic inet having an upper horizontal cross member separati the freezing compartment open on its rear face, from refrigeration compartment and an agregat which may sealing by fitted into the cabinet, said agregat prising the refrigerating unit and a vertical ar plate made from an heat insulating material, fitt to enclosing the opening formed in the rear face of the -k4 not, a' I 2a The present invention comprises an absorption-diffusion refrigerator comprisi.- a lower refrigeration compartment, an upper freezing compartment and an absorption-diffusion refrigerating unit, said refrigerator being an assembly of two parts which can be fitted one into the other, namely a parallepipedic cabinet open on a rear face, having an upper horizontal cross member separating the freezing compartment from the refrigeration compartment and an agregat which may be sealingly fitted into the cabinet, said agregat comprising the refrigerating unit and a vertical rear p,.ate made from a heat insulating material, S o fitted to close the rear face of the cabinet, this vertical rear plate including a forwardly extending insulating box engageable in a volume defined between a upper horizontal wall, the horizontal cross member and Svertical side walls of the cabinet, wherein the vertical Srear plate extends substantially over the whole height of the cabinet, the lower refrigeration compartment of the cabinet being closed by a lower part of the insulating vertical rear plate which contains a lower part of an evaporator, and the cabinet and agregat walls of rigid insulating material being directly fitted intimately in each other without the interposition of a tearable insulating fiber fabric.

p 3 In the rest of the description the assembly of the refrigerating unit and its specific insulation and its diffusing plates will be designated by the term "agregat", the whole forming an assembly which may be manufactured separately and assembled together with the cabinet.

Refrigerator is characterized in that the vertical rear plate extends substantially over the whole height of the cabinet, the lower refrigeration compartment of the cabinet, open on its rear face, is closed by the lower part of the insulating vertical rear plate which contains the lower part of the evaporator, and the rigid insulating material walls of the cabinet and of the agregat are fitted intimately in each other directly without the interposition of a tearable insulating fiber fabric.

The refrigerator according to the invention offers the advantage that its two component parts namely the cabinet and the agregat may be manufactured in different 0 places and assembled together at the place of use. The S" agregat which forms the most complex and most expensive part may be mass produced in a given place adapted more particularly for such manufacturing, whereas the cabinet itself may be readily manufactured on the spot, even in a country not having very sophisticated manufacturing means, because its structure is relatively simple.

Although the refrigerator is made from two independent parts assembled together, because of a judicious design of the assembled elements, its provides an excellent thermal ra~L; insulation, by simple fitting together in direct contact of its two parts, without the interposition of a tearable insulating mat of the glass fiber type. With such an insulation, in the freezing compartment, very low temperatures may be obtained, going down to -181C, even in the case of external temperatures reaching or exceeding 40 0 C. Furthermore the agregat is correctly positioned inside the cabinet during the assembly thereof, because of the provision of appropriate guide elements. The refrigerator also provides a good distribution of the cold inside the freezing compartment because the tube of the evaporator is fixed to a rigid lining made from a good heat conducting material forming the internal face of the compartment.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more readily understood on reading the following description with reference to the accompanying drawings, in which Figure 1 is a schematic simplified perspective view of the two main parts of the refrigerator according to the invention, before these two parts are fitted one into the other.

Figure 2 is a partial horizontal section view through line 11-I of figure 1, the refrigerator beit'g assumed assembled.

Figure 3 is a partial horizontal section view through line II-IIl of figure 1, the refrigerator being assumed assembled.

Figure 4 is a vertical section view through lines IV-IV of figure 1, the refrigerator being assumed assembled.

Figure 5 is a pert,ective view of the refrigerating unit assembly, without all its component elements being shown.

Figures 6,7 and 8 are perspective views illustrating different embodiments of the upper part of the evaporator associated to the freezing compartment.

Figure 9 is a perspective view, on a larger scale, showing the connection between the tube in w,.ich the refrigerant flows and the internal wall of the box- defining the freezing compartment.

The absorption-diffusion refrigerator according to the invention is formed of two main parts fitted one into the namely a cabinet 1 having a general parallelepipedic shape, and an agregat 2 which may be fitted into this cabinet, Sfrom the rear thereof. The cabinet 1 comprises a base 3 from which extends two vertical side walls 4 and 5 parallel to each Sother, these two walls being connected together, at thei. upper parts, by an upper horizontal wall 6 and an intermediate horizontal cross member 7. All the walls 3-6 and the cross member 7 are made from a rigid heat insulating material such as a plastic material foam of the same thic:ness a (for example The base 3 and the cross member 7 define a lower refrigeration compartment 8, whereas the cross member 7 and the upper horizontal wall 6 define an upper freezing compartment 9. The cabinet 1 is completed on its front face, by appropriate doors, not shown, for closing respectively the lower refrigeration 8 and upper freezing 9 compartments.

The rear vertical face of the cabinet 1 is left totally opened so that the fitted agregat 2 may be applied thereagainst. This agregat 2 comprises all the elements of the refrigerating Unit 11 which is shown schematically as a whole in figure 5. The agregat 2 comprises a vertical support plate 12, of a rectangular shape, made from a rigid heat insulating material, the shape thereof correspondinj ,to that of the 1 j- 6 opening of the rear face of the cabinet so that it can be fitted in to this opening and completely close it. This insulating support plate 12 is e::tpnted forwardly, at its upper part, by an insulating box 13, open to:,ards the fiont and to the bottom, defined by an upper horizontal wall 14 and two vertical side walls 15 and 16 extending downwardly. The external dimensions of the insulating box 13 are choosen so as to correspond closely to the internal dimensions of the upper freezing compartment 9 of cabinet 1.

Preferably the vertical side walls 15,16 of the box 13 converge slightly forwards towards each other and the upper parts of the internal faces of the vertical side walls 4,5 of cabinet 1 have the same angle of convergence and similarly the upper wall 14 of the box 13 is inclined slightly from top to bottom and from the rear to the front, as well as the internal or lower face of the upper horizontal wall 6 of cabinet 1, so that the box 13 may be fitted with a tight fit into the upper freezing compartment,9 of cabinet 1.

In addition, the lower faces of the vertical side walls 15,10 of box 13 are inclined slightly from bottom to top and f.'om the rear to the front so as to be able to slide over positioning and guide grooves or ramps 17,18 which are formed on the sides of the upper face of the cross member 7, these grooves 17,18 having the same slope as the lower faces of the walls 15,16 of the box 13. These grooves 17,;$8 ake it possible to obtain accurate positioning of the agregat whith respect to the cabinet itself previously set horizontally, for complying with the flow slopes required for the refrigerant.

As it can be seen in figure 2, the vertical side faces 12a of the support plate 12 are slightly convergent inwardly so as to be applied against bearing faces having the same slope 7 such as the bearing face 4a, provided in the rear par;- of the internal faces of the vertical side walls 4,5 of the cabinet.

Similarly the lower horizontal face 12b of the support plate 12 (figure 4) is preferably inclined slightly from bottom to top and from the rear to the front -o as to come to bear on an upper face 19 having the same slope provided in the lower d rear part, forming a shallow bottom 20, of small height of cabinet 1.

The support plate 12, made from a rigid insulating is fixed, on its rear face, to a vertical metal plate 21 which extends over the whole height of the cabinet and which covers the rear vertical wall forming the lower bottom 20 of the cabinet.As it has been said formerly, the refrigerating unit 11 is supported as a whole by the agregat 2. This unit 11 comprises, at the rear of the vertical insulating plate 12, a vertical boiler 22 whose upper end is connected through a tube 23 to a condenser 24 which is fixed to the upper part of the vertical plate 12, externally thereof. The output orifice of condenser 24 is connected by a to an evaporator 25 comprising two parts, namely an upper part 26, housed in the upper box 13, for creating a low temperature in the upper freezing compartment, and a lower part 27 creating a relatively higher temperature in the lower refrigeration compartment. The tube forming the Upper part 26 the evaporator is bent so as to be able to follow a given path inside some or all the insulating walls forming the upper box 13. Over the whole of its path the tube ,orming the evaporator 25 has the same slope so as to provid an even refrigerent flow.

In the embodiment of the invention shown in figures ind 6 the box 13 has a vertical cross section in the form of Ian upturned in other words it is opened at its lower part.

The tvbe forming the upper part 26 of the evapor'ator housed in the box 13 forms successively a loop 28 extending forwardly, inside the upper horizontal wall 14 of the box 13, then a tube s 29 housed in the upper part of the vertical wall J12, ten an hairpin 31 extending horizontally forwards inside the vertical left wall 15, then a tube section 32 housed in the upper part of the vertical wall 12, then a forwardly extending hairpin 33 housed in the vertical right wall 16 of box 13, then a tube section 34 housed in the upper part of the vertical wall 12 and~ connected to the lower part 27 of the evaporator.

This lower part 27 comprises a coiled pipe housed completely in the lower part of the vertical wall 12 forming the bottom of the rpfrigeration compartment, and it is connected, through an absorber ,not shown, to a refrigerant reservoir 35 itself connected to the base of the boiler 22, in the variant of the invention shown in figure 7, .the box 13 is closed, at its lower part, by a lower horizontal wall 36 intended to be positioned just above the cross- member 7 of the cabinet. In this case the cross member 7 and the lower wall 36 of the box 13 each have a reduced thickness so that the sun of their thicknesses corresponds substantially to the LJthickness a of the different insulating walls of the refrigerator.

In this embodiment the lower hor,',zontal wall 36 also contains an additional lovp 37 formed by the L, ~f the upper part of the evaporator, this additional loop extending between the tube 34 and the lower part 27 of the evaporitor. Thk five insulating walls of the box 13 consequently each contain a section of the tube forming the Upper part of the evaporator.

In the variant of the invention shown in figure 8 the box 13 is of the type shown in figur6 6, namely 'opened at its lower part, and the upper part of the evaporator is limited to the two hairpins 31,33 housed respectively in the two walls 15,16 of the box 13, and to the three tubes 29,32,34 housed in the upper part of the vertical wall 12, Figure 9 illustrates the way in which the tube of the evaporator and the inside of the freezing compartment are connected together. This compartment is defined ,inside the insulating walls 14,15,16 And possibly 36 o f 13, by a rigid lining 38, for example pressed, made f r om a good heat conducting material, such as an aluxninium sheet, which is applied to the internal faces of the insulating walls and which may have ribs 39 projecting inwardly which follow the path of the tube 41 of the evaporator. These inwardly projecting ribs 39 form, outwardly, grooves in which the tube 41 is partially housed and fixed, for example, by welding, crimping or bonding.

Thus an intimate connection is provided between the tube 41 and the internal metal sheet 38, which promotes the transfer of negative calories towards the- inside of the freezing compartment.

Claims (11)

1. An absorption-diffusion refrigerator comprising a lower refrigeration compartment, an upper freezing compartmet and an absorption-diffusion refrigerating unit, ;said refrig- .icor being an assembly of two parts which can be fitted one into the other, namely a parallepipedic cabinet open on a rear face, having an upper horizontal cross member separating the freezing compartment from the refrigeration compartment and an agregat which may be sealingly fitted into the cabinet, said agregat comprising the refrqerating unit and a vertical rear plate made from a heat insulating material, fitted to close the rear face of the cabinet, this vertical rear platl including a forwardly extending insulating box engageable in a volume defined between a first upper horizontal wall, the horizontal cross member and vertical side walls of the cabinet, wherein the vertical rear plate extends substantially over the whole height of the cabinet, the lower refrigeration compartment of the cabinet being closed by a lower part of the insulating vertical rear plate which contains a lower part of ai1 evaporator, and the cabinet and agregat walls of rigid insulating material being directly fitted intimately in each other without the interposition of a tearable insulating fiber fabric,

2. Refrigerator accord ig to claim 1 wherein the insulating box, open towards the front, is defined by an upper part of the vertical rear plate, a second upper horizontal wall and two downwardly extending vertical side walls, the external dimensions of the insulating box being chosen to correspond closely to internal dimensions of the upper freezing compartment of the cabinet.

3. Refrigerator according to claim 2 wherein the 1 Ii j if" i~99 11 vertical side walls of the insulating box converge slightly forwards towards each other, the upper parts of the internal faces of the vertical side walls of cabinet having a same angle of convergence, the upper wall of the box being inclined slightly downward from the rear to the front, as well as the internal or lower face of the upper horizontal wall of cabinet, so that the insulating box may be tightly fitted into the upper freezing compartment of cabinet.

4. Refrigerator according to claim 3 wherein the insulating box is open at its lower part and the lower faces of the vertical side walls of box are inclined slightly upward from the rear to the front to slide over positioning and guide grooves or ramps which are formed on the sides of the upper face of the cross member, these S* grooves having a same slope as the lower faces of the O n vertical side walls of the box.

Refrigerator according to any of the preceding claims wherein a tube forming an upper part of the evaporator extends inside the vertical side walls of the box, and the upper part of the insulating vertical rear plate.

6. Refrigerator according to cla-m 5 wherein the tube forming the upper p-rt of the evaporator also extends inside the upper horizontal wall of the box.

7. Refriqerator according to any of the claims 2 to 6 wherein the insulating box is closed at its lower part, by a lower horizontal wall adapted to be positioned just above the cross member of the cabinet, the lower wall of the box and the cross member each having a reduced thickness such that the sum of their thicknesses ccrresponds substantially to the thickness of other insulating walls of the refrigerator. -12

8. Refrigerator according to claim 7 wherein the tube forming the upper part of the evaporator further extends inside the lower horizontal wall of the box.

9. Refrigerato according to any of the preceding claims wherein the vertical side faces of the vertical rear plate are slightly convergent inwardly to be applied against bearing faces having a same slope provided on rear parts of the internal faces of the vertical side walls of the cabinet, the lower horizontal face of the vertical rear plate being inclined slightly upward from the rear to the front so as to bear on an upper face of a lower rear part of the cabinet, the upper face having a same slope as the lower horizontal face of the vertical rear plate, the lower cear part of the cabinet extending a small height from the bottom of the cabinet. o

10. Refrigerator according to any of the preceding claims wherein the freezing compartment is defined, inside the walls of the insulating box by a rigid pressed lining made from a good heat conducting material, such as an aluminium sheet, which is applied to the internal faces of the walls of the insulating box and which has ribs projecting inwardly, the ribs following the path of the tube of the evaporator, said tube being partially housed and fixed in the ribs.

11. A refrigerator substantially as hereinbefore described with reference to the accompanying drawings. Dated this 6th day of April 1990. ASSOCIATION POUR LA RECHERCHE ET LE DEVELOPPEMENT DES METHODES ET PROCESSUS INDUSTRIELS Patent Attorneys for the Applicant F. B. RICE CO.