CA2027716A1

CA2027716A1 - Process for the production of a plate condenser for a refrigerating machine, especially for a household refrigerator, as well as special plate condensers produced according to theproces

Info

Publication number: CA2027716A1
Application number: CA002027716A
Authority: CA
Inventors: Horst Lingemann
Original assignee: Helmut Lingemann GmbH and Co KG
Current assignee: Helmut Lingemann GmbH and Co KG
Priority date: 1989-10-16
Filing date: 1990-10-16
Publication date: 1991-04-17
Also published as: DE3934479C2; DE3934479A1; DE8912272U1; EP0423500A2; JPH03133566A

Abstract

Abstract Procedure for the manufacture of a plate condenser (1) for a cooling device, in particular a refrigerator for household use, in which a pipe in the shape of a cooling coil is installed and attached to a tin plate (2), especially one made of aluminium, and a black coating (5) is applied to the other side, and which should be developed in such fashion that the improved heat transfer between the pipe (4) and the plate (2) makes it possible to manufacture it in a simple and economic way. This is achieved by using a pipe (4) and/or a tin plate (2) coated with a layer of soldering material (6), i.e. a material based on an aluminium/silicon alloy, on the surface facing the other part (2, 4), and in which the black coating (5) is applied before installing the pipe (4) onto the tin plate (2), and then the pipe is brought in contact with the tin plate (2), and the points of contact are essentially soldered along the entire length of the pipe (4).
The invention refers to a plate condenser (Figure 1).

Description

21)2771~

Code: 3~3-~7 .
PRO OESS FOR ~ PRG~CTION OF
A P~A~E CO~DENSER FOR ~ ~EE~IGERA~ING MaC~I~E, EsPEcT~T~r.Y FOR A ~O~SE~OL~ RE~RI~ERATORr AS WELL AS -SPECIAL PLA~E CON~ENSE~S PRODU~ED AccoRDr~G TO TEE P~OCESS.

~ he invention concerns a process a~d~or a plate condenser acco-ding to ~he char cteristics of Claims 1 and A refrigerator is a stationary or mov~b~e device ~or the ~-~
- refrigera~ion o~ enclosad spaces and the solidr liq~id or gas ~orm obje~s t:herein to a prese~ temperzL~re, ~ha~ is lower than ~at of i~s surroundings. For this purposa, heat; mus~ be .
e~tracted ~rom the o~je~s and dis~harged ~ to ~hP su~roundings.
A ~late condenser:serves ~or the latter p~rpose, in which ~he .
. heat transport is ~aken over by a re~rigera~t ~Frigen~
~he pri ary structu~l elemen~s o~ ~ pla~e ~ondenser are a panel-shaped ~piece o~] me~al or a ~et~l pla~e, onto w~ich a cooling ~oil o~ tubing is posi~ioned and mounte~. ~he .
re~rigeran~ circulates through ~he tu~e. ~he p~rpose o~ ~he pla~e is to increase the heat tran~er be~wee~ ~he ~ e and it~
surrounaings. ~herefore, a satis~c~ory ~ea~ transfer be~ween the tube and the pla~e, ao well as betwee~ the plate ~n~ its surro~ndings, i~ des~e~. ~or.an lmprovement o~ the.hea~
disoharge ~o ~he suxrounain~s ~,~nown process is ~o bl~cken ~he si~e o~ the plate.which is opposite ~he tube. . -A pro~ess $or the pro~u~tion of ~ pla~e condensër has `
re~dy been sugges~ed, in wh~h the tu~e is glued on~ the plate~ In this process the pl~e is ~ut ~o size, the adhesive . ,, . .. .. . .... . . ................... _. .............. .. . ~ .

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~aterial is applie~ to the upper side o~ ~he generally horizontally positione~ pla~e, ~he tube is laia onto ~he ~pper side of the plate ~nd then the adhesive m~erial is h~rdene~ by hea~ application. The pla~e is ~hen t~rned and bla~kened, so ~hat the black layer is applied to the other, now upward :
pointLng, side. This l~yer is ~hen also hardened by heat application.
With a plate cohden~er tha~ w~s p~odu~ed ~oord~ng to this pro~ess, ~he stabili~y o~ t~ ~onhection might present a problem, especially if it is ~onsidered tha~ the ~emperat~re fluctuations ~reate ~er~aln tensions in ~ he conne~tion, so that especiaily suitable and expe~si~e 2dhesive materia~ must be used, ~hic~ ~n turn in~rease the production ~os~s. The sui~able adhesive ma~erials are ~lso not consiaered good heat conductors.
Furthermore, the slze of ~he result~ng conneGtion area is .
rela~ively small, whi~h 1~ turn influences the heat trans~er.
The task o~ the invention i~ to further ~evelop a pro~essr.
accordi~g ~o ClaIm 1, or a plate con~en~er, a~coraing to ~la~m 1~, in s~c~ a way ~hat the simple and inexpens~ve prodDc~lon~
with simultaneous ~ssurance o~ increased hea~ tran~er, is made possible. .
This task is solved by.the charac~eristi~s of Clai 1.
In the process aGGo~ding ~o the ln~e~tlon, a ~ube o~
aluminum and/or a plate o~ aluminum are used, whîch is l~yered or plate~ with solder o~ the s~de tha~ adjoins with the aorrespond~ng par~. The t~be and the plate axe the~.soldered ~ -~oge~he~ This ~eans that an intermediate product in form of a tube ana/or a plate is used, in which ~he bona~ng m~terial.~an ~e applied in an e~sy and ~nexpen~ive ~nner du~ing the p~odu~tion .. . . . . . .. . . . . . . . . . . .

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of ~he tube and~or the plate or be~ore ~he attachment o~ th~ tube onto the plate in ~uch a way that, during the soldering of th~
p~ate condenser, no more such applica~ion h~s ~o be executed.
solder~ng connectlon ~etween the ~e an~L the plate represents a measure that not o~ly result~ in ~ hig~ s~ilit;y of t~e .
connection, bu~ also, for one, becau~e o~ the good he~
conducti~ity of the solder, and, ~or the o~her, ~ecause o~ ~e solder~ng seam wi.h con~ex solde~ accl~mulation, whic~ is automatically ~ause~ by 2~e~ion, res~lts ~ a ~ett~r he~.
trans~er between the ~ube and ~he pl~te. In the process according to ~he l~ven~on~ the blackenlng or kl~ck ~oating o~
the pla~e is also e~ecuted be~ore the soldering~ so that a blac~ened plate or a plate with ~ blaek layer ean be used as intermedia~e prod~ct and a ~12ckenlng or coatlng after the ~
soldering is not necessary~ ~he pro~ess a~cor~ ng ~0 t~e ~:
~nven~ion makes possible the producti~n o$ a pl~te condenser in an easier, aster znd less cos~ly manner possible. A ~la~kening -;
or ~lack coa~ln~ o~ the solder-coa~ed or solder-plat~d pla~
(intermedia~e produGt) should be provided ~or, which c~n ~e exposed to the necessary ~e~p~ratuIes that occur dur~ng . :~
soldering, without impairment o~ the same. ~:
The previous~y desGr~bed ~dv~nt~es are a~so ~a}id ~or the pla~e condenser accordi~g to Claim .16.
Further advan~a~eo~ developmen~s o~-the in~ention, who~e ;~
characteris~ics contrlbute to the solution ~f the task and ~lso .
include a black coati~g th~ is especia~ly suitable for the ~ro~ess or ~he plate conaenser according to the in~ention are .
described in the su~claims. : :

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-~ 2~277 , 4 ~ -In the ~ollowing ~he in~ention is described more c~osely by drawings, which represent pre~erred examples.
Figure I shows a plate ~onden~er according to the inven~ion, wi~h a view o~ ~he ~ace sidet on w~i~h the ~ube is loca~ed;
Figure 2 shows the se~tion a~ross ~e t ine ~ igure 1 in ~larged representation; :
~ igu~es 3-~ show the corresponding sections in Figure: Z in al~ered examples.

~he plate Condehser 1 acCordiAg ~0 the ~vention consists G~
a panel-shaped or plate-shapad ~piece of] metal 2, which pre~erably has a rectan ~ ar or square shape, onto whose one ~ace side is soldered tube 4 of ~out 4 mm to 6 m~ diame~er~ th~t is formed by refrigeration tube 3 in a meander shape. ~he o~her : race side of the me~al plate 2, which opposes the tube ~, is fur~ished wi~h a black coatin~ 5 ~hat induces an increased he~t ' discharge. The ~etal plate.~ and ~he tub~ 4 ccnsist of alilminum or a~ aluminum alloy.
T~e plate condenser 1 is in~ended ~or a hous~hold refri~erator ~appliance~ and is, in mounted position, located on the back side of the refri~erator in vertic~l pos~tlon, where the ~ace side of the plate condenser l whi~h o~ies the tube 4 ~aces the re~rigerator, while the ~ace sid~ w~ich carries the bl~ek coatLng g ~aces ~w~y ~o~m the refrigeratox. During opera~i~n o~
the rerrigerator the heat t~a~ was extracto~ fr~m the cooling .~
objects in5ide the refrigerator is disch ~ged i~to ~he .
~urroundings by the plate condenser 1~ ~ere ~he heat transpo~t i~ ob~ained ~y circula~ion of a re~rigerant ~hrou~h.the tube 4.
The heat which should be discharged by the plate condenser 1 is then discharged by the tube ~ itsel~ and the metal plate!2! w~ere . - -~ .
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a large part o~ ~he heat con~ained in the tube 4 is trans~err~
onto the metal plate i by t~eir ~onnec:~ion. ~he tube 4 is soldered over ~he whole extend in the area of the me~al plate 2 in such a way that a ~ine-s~aped soldere~ connection is obtained.
This r~sults in a large hea~ trans~er profile be~ween ~he -~ube and the me~al plate ~. ~olaering is especially sui~ble ~or ~he connection because it is, . ~or one, relatively solid s~d~ ~or the -~
o~her, a coldered connect1on r~sults ~utom~ically i a ~ :
~elatively large connec~ion pro~ile~ because ~he so~der contracts ~o a relat~vely iarge connection ar~a, caused by the au~o~atically occurring adhesion. ~exe ~he concave rouhded siae sur~ces o~ the Gonnection area result, w~ich con~r~bute to the desired large connection profile.. Any soldering ~aterial whioh is suitable for the soldering of aluminum can be used~
Ac~ordl~g ~o ~he ~ n~en~i~n, ~ least one side o~ ~e ~et~
.....
pla~e 2 and ~he ~ube 4, who~e ~urfaces will ~e connea~ed ~o each other, is layered wit~ the solderi~g material, so that the me~
plaie 2 and/or the tN~e 4 with the solder layer ~orm a prefabrica~e~ i~texmediate.product wi~h a prefer~ rolled lamina~e~ In the examples acco~ding to Figure.l and 2, the ou~side of the tube a is ~urnished with the solde~ Ia~e~ 6. 5~ch .. :
tu~e is ~ormed ~rom an aluminum strip which is solder pla~ed on ~ ~
one side~ in such a way ~ha~ the strip is pulled throug~ a. - ;
forming mold (Formose), whiçh corresponds with the profile.of the tube, #o tha~ the sol~e~ l~yer 6 is located osl the outside and .
the desired ~e pxo~ile w~h a longitudinal joint ~s o~tained.
~he longitudinal edges of t}le join~, which are marked as 7 i~
Ff,gure 2, o~ the strip tha~ was shaped into ~L tub~ are connecled ti~htly with each other, p~eferably by weldin~, ~or which ., " ~
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high-~requency welding is espeoially suitable. ~he ~h~s ~ormed tube ~s bent to a shake cooling coil or meander shape ~efore it is atta~hed to the metal plate ~, ~her~ore it has to be o~serYed that the joint 7 shows a d~stance ~rom the li~e- or st~p-shaped a~oining axea ~ o~ the tube 4. Pre~era~ly the joint 7 ls positioned on the side o~ the tub~ 4 tha~ fa~es away fro~ ~he metal plate 2. ~he ~older l~yer ~ on the ~u~e.4 ~s~r~p) and/or t~e metal plate 2 can be ~ery thin.
Fo~ the soldering process the previously bent ~u~e 4 is ~aid onto the horizo~ally posi~ioned metal plate 2 and p~efe~a~l~
pre-~lxed or pressed agains~ the metal plate 2, whi~h G~n, *0 example, be obtained by a ~eight or point by poin~ fi~ation o~
the refrigexa~ion tubes 3~ .
The pos~tioning o~.the re~rigerat~on tu~es 3 is pre era~ly such that the tu~e 4 begins ~t the ~otto~ and then e~ends upwa~d, where ~he re~riger~tion ~u~es 3 ~orm a horizon~al e~nder shape, ~nd then Goh~inues vert~cally downwar~ again Oh one.si~e with the ~u~e section 3. ~he solder path, wh~ch e~ten~s over the entire length o~ the ~ube 4 ~e~ween ~he lat~er:and the me~al plate 2 and whic~ automatically ~ox~s ~uxing the soldering process, is markea with 11.
- The coa~ing 5 mus~ ha~e s~h a ~emperature resistance that it is not ~ p~ired by the te~pera~ures ne~e~s~r~ fo~ the solaeri~g process, which is, in these e~dmples, abo~ S90'~ T~e co~ting 5 is pre~erably a Yarnish or a la~quer, which is applied n only one layer ~ one - coat varnish) . A roller application is very.suitable ~or ~his purpose, which is preferably ~nple3nented with ~ c:o~l coating appara~us~ The coa~ing 5 can also }~e applied vo~y thin in ~orm o~ a f il~n . Exper~nen~s showed tha~ a ~ry ~il~
... _.... , ........... , , -~ ` : 2 ~ 2 ~
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layer thickness o~ 10 to 20 ~m is espe~i~lly suitable and Gan be produce~ cost-ef~iciently. The hardenin~ o~ ~he coating 5 or t~e :
lacquer~ which was applied Ln liquid for~, is pre~erably executed by heating or baking. ~dvantageous results were obtained wit~ a baking ti~e of at least abou~ 1~0 sec ~nd a baking ~e~pera~ure or ~
about 350~C. A minimum objective temperzture ~ 2~oc sho~d be ~-rea~hed.
O~her experi~ents resulted i~ ~he fact tha~ a coating ~
venyl~ethylpolysiloxane tsic; Phenylmethylpolysilo~ane~ res~h is : ~:
especially sui~a~le, Suc~ ~ la~quer pre~er~bly ~onsists o~
:: . ~ .
Phenylmethylpo~ysi.loxane resin .
~or example S;~ikophen P 50/300 50% in xylene/isobutanol abo~ 50 to 80 espe~ially ~5 parts Splnel Black C~ (cr, Fe~2 04 for examp~e T~ Black 100 about 5 to 11 especially 8 p~rts ~:
' .. :-Soot, for exa~ple Corax L about ~.5 to 3 especially zpartF

Calcium-mag~esium silica~e ~or example Plastorit 0000 about ~ ~o 8 espeaially 6 par~s Zinc ~ho~phate Zn3(PO4)~
~or example ~eucophos ZP0 about 4 ~o ~ e~pecially ~ part~

Mon~morillon~te layer silicate ~or example Betone 38, 15% ~out 0.5 to 3.5 especi~lly 2 p~rts .

, .. ... , ............ _ ,_ . . . . ....... .

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2027~ ~

Cy~lohe~anone ~bou~ 9 to 13 especially 11 par~s 100 parts Figure 3 show~ ~ se~tion through a pla~e condenser 1, accord~hg to Figure 2, in which no~ ~he ~u~e 4, ~ut the m~l plate Z is solder pl~ted, ~his means *urnished with a solder layer 6.
. Figure 4 shows a se~tion through a pla~e ~ondense~ l,.in ~hich ~he metal plate 2 ~hd the tu~e 4 are sol~er p~ated or furnished wit~ a solder layer. . :
In order ~o ~rea~ a solder p~th 11 with the largest possible pro~ile or the la~ges~ poss~ble w~h, a tu~e shou~d ~e used that adjoins the me~al plate 2 two-dimensionally. 'A lat ~:~
presse~ tube, according to Eigure 5, or a square tube, ~c~ording to Figure 6, are very suitable for this purpose. Good results, :
however~ ~ere also ob~ained with a ~ircul~r tube, ac~ordin~ ~o ~:
Figure 2~ .
~ he applica~lon o~ the solder l~yer ~ onto the me~al plate 2 or the ~ube or ~he ~lat strip which will la~er ~orm the tu~e can be c~cuted ~n one o~ the ~ollowing processes;
~ac~u~ so~dering process ~wi~hout flu~
~lux soldering process ~wi~h ~lux) or Nocolok soldering p~o~ess ~with ~lu~) ; ~ "

202'7'7~ :
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-, , In ~he ~se in w~ic~ the metal pla~e Z is coated with the . solder layer ~ on the side that opposes ~he black co~ting ~, a -:
metal plate with two-sided ~lack coating can be used in the ~orm o~ an intermediate p~oduct, which simpli~ies the produc~ion and lowers the production cos~s.
The material ~or the solder or the solder layer ~ can be a ; ~aterial on the ~ase o~ ~n.alum~num~silicon alloy~
~ n the mass produ~ion o~ ~he met~l plate~ the metal plates 2 are prefera~ly cut from a ~et~l band whiGk has, as an in~ermediate produc~, a blaak ~oating ~ on o~e si~e and, in :.
cer~ain cases, the sol~er l~yer ~ on the o~her side. It is, ; there~ore, coated on one side or on both sides. This furthermore s~mpli~ies and economizes the production.
~n the ~ollowing ~e different steps ~or the pro~uc~ion of a i. plate condenser 1 are described.
Supply o~ a ~piece3 metal, especi~lly a m~l ba~ wi~h a so~der laye~ on one ~ace side ~hd a black coating 5 on the other *a~e si~e, especial~y in a pasi~ion in w~ic~ t~e ~lack coating S
is pointed downward.
~ ~pp~ication o~ ~he ~}ack c~a~ing 5.
; Cu~ting Of ~he met~l plate ~ ~e~ore or after the applica~ion ~ :
o~ th~ black coatLn~ 5r or e~eh ~fter the soldering process. ~ -}~ent of ~ pxe~riaz~ted me~er-sh~ped tu:~e ~ ~nt~ he m~tal plate 2, in which the correspondihg f~e side of the ~e~
plate 2 and~or ~he sur~ace o~ the t~e 4 c~n be solder p7ated~ -If ~ecessary~ pre- ixation of the tu~e A with the metal plate Z and hea~ing to ~oldering ~emperature~ ~nd preferabiy simultaneous soldering of the uni~
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It is also possi3:)1e to use metal pla~es 2 or ~e~al. bands ; t~at were furni~hed with a black coating ~ dl~ring 'che p:cef~:ri~ation process (inter~ediate produc~ 7i~L the use o~ a met~l b~nd or a ~u~e 'ch~t c~n ~e dr~ from ~ roll, i~ might ~e necessary to adjust t:h~ band or t~e ~u~e ~ er the drawing process. . .

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Claims

1. Process for the production of a plate condenser for a refrigeration machine, especially a household refrigerator, in which a meander-shaped bent tube of aluminum is positioned and mounted on one side of a metal plate, which preferably consists of aluminum and a black coating is applied to the other side of the metal plate, characterized by the fact that a tube (4) and/or a metal plate (2) is used, onto whose surface that faces the corresponding other part (2, 4) a solder layer (6), for example on the base of an aluminum/silicon alloy, is applied and on which the black coating (5) was applied before the the attachment of the tube (4) onto the metal plate (2) and then the tube is laid on the metal plate (2) and soldered over the entire length of the tube (4).

2. Process according to Claim 1, charaterized by the fact that a solder-plated tube (4) and/or metal plate (2) are used.

3. Process according to Claim 1 or 2, characterized by the fact that the black coating (5) is applied onto a metal band in a size that corresponds with the measurements of the metal plate (2) and that the metal plate (2) is cut and separated before or preferably after the soldering process.

4. Process according to one or more of Claims 1 through 3, characterized by the fact that a band, which is coiled around a roll, is drawn from the roll and the black coating (5) is applied before or after the cutting or separation process.

5. Process according to one or more of Claims 1 through 4, charaterized by the fact that a tube duct band, which is coiled around a roll, is drawn from the roll preferably parallel to the metal band and bent before or after the cutting process.

6. Process according to one or more of Claims 1 through 5, characterized by the fact that the metal band is conveyed to the cutting process in horizontal position with the black coating (5) on the underside.

7. Process according to one or more of Claims 1 through 6, characterized by the fact that the metal plate (2) is conveyed to the attachment of the tube (4) in horizontal position with the black coating (5) on the underside.

8. Process according to one or more of Claims 1 through 7, characterized by the fact that the tube (4) is pre-fixed during positioning or during or after laying onto the metal plate (2).

9. Process according to one or more of Claims 1 through 8, characterized by the fact that the black coating (5) is obtained by application of a special material.

10. Process according to Claim 9, characterized by the fact that the black coating (5) is applied in a liquid paste manner.

11. Process according to one or more of Claims 9 and 10 characterized by the fact that a lacquer is used for the black coating (5).

12. Process according to one or more of Claims 9 through 11 characterized by the fact that the black coating (5) is applied in one layer.

13. Process according to one or more of Claims 10 through 12, charaterized by the fact that the black coating is dried and baked by heat application.

14. Process according to Claim 13, charaterized by the fact that the black coating (5) is dried or baked at a minimum objective temperature of about 200 to 320°C, especially 260°C.

15. Process according to Claim 13 or 14, characterized by the fact that the black coating (5) is dried or baked over a duration of about 60 sec to about 180 sec, especially about 120 sec, at a temperature of about 200°C to 300°C, especially about 350°C [sic].

16. Plate condenser, which is produced according to one or more of Claims 1 through 15, with a metal plate, which preferably consists of aluminum, on whose one side a tube of aluminum is positioned and mounted in a meander shape and on whose other side a black coating is applied, characterized by the fact that the tube (4) and/or the metal plate (2) are coated with a solder layer (6), for example on the base of aluminum/silicon alloy, on the surface which faces the corresponding other part (2, 4) and that the tube (4) is continuously soldered with the metal plate (2) along the tube (4).

17. Plate condenser according to Claim 16, charaterized by the fact that the tube (4) and the metal plate (2) are solder plated.

18. Plate condenser according to Claim 16, or 17 characterized by the fact that the black coating (5) is temperature resistant to about 590°C. preferably to about 650°C.

19. Plate condenser according to one or more of Calims 16 through 18, charaterized by the fact that the black coating (5) is a layer which is formed by application of a separate material.

20. Plate condenser according to one of Claims 16 through 20, characterized by the fact that the black coating (5) is a layer which was applied in a liquid or paste manner and then hardened.

21. Plate condenser according to Claim 20, characterized by the fact that the black coating (5) is dried or baked by heat application.

22. Plate condenser according to one or more of Claims 16 through 21, charaterized by the fact that the black coating (5) is applied in one layer.

23. Plate condenser according to one or more of Claims 16 through 22, characterized by the fact that the profile of the tube (4) is round or flat, preferably rectangular, square, oval or flat pressed, on its adjoining side.

24. Process or plate condenser according to one or more of Claims 1 through 19, characterized by the use of a lacquer for the black coating (5).

25. Process or plate condenser according to Claim 24, characterized by the use of a lacquer on a phenylmethylpolsiloxane resin base with the following preferred contents Phenylmethylpolysiloxane resin for example Silikophen P 50/300 50%, in xylene/isobutanol about 50 to 80 especially 65 parts Spinel Black Cu (Cr, Fe)2 04 for example True Black 100 about 5 to 11 especially 8 parts Soot, for example Corax L about 0.5 to 3 especially 2 parts Calcium-magnesium silicate for example Plastorit 0000 about 4 to 8 especially 6 parts Zinc phosphate Zn3(PO4)2 for example Heucophos ZPO about 4 to 8 especially 6 parts Montmorillonite layer silicate for example Betone 38, 15%, about 0.5 to 3.5 especially 2 parts Cyclohexanone about 9 to 13 especially 11 parts 100 parts .