DE2006469A1 - Process to accelerate the defrosting of a normal cooling compartment evaporator and refrigerator to carry out the process - Google Patents

Description

Procedure for accelerating defrosting of a liormalkulilfaeh ~ Verdanipfers and

aur! Carrying out the procedure

The invention relates to a method for Beachleu *. inclination to defrost a wood heater aoh ^ evaporator

* ' ^{v of} a refrigerator or

the like of liquid refrigerant during the for !! temperature control brought about standstill sides of the Chiller »; and a drain tank or the like ! Carrying out this procedure · ■■

Bnter a Norraalkühlfach ^ at iia purposes of the invention $ ia refrigerating compartment understood, in which food or the like can be stored at temperatures "the I above d ^ söefrierpunldies are water _and, the-B0 öaß not food freeze * JSM sufficient cooling of the cooling fan When the temperature is reached, the normal steam is cooled down to below the freezing point of water during the running times of the cold oma-bohine, which results in lltmm E @ if ßiedsr, which defrosts during every downtime of the KlItemuohine must be, "the cooling capacity? eröarapfers would the affect and other ffaohteile has * defrosting can published in a known manner by heating the evaporator or by natural warming (follow because otherwise constitutes an increasingly thicker Bdifeohlcht. When defrosting by natural The procedure is done in such a way that one feels the surface temperature of the terderapftrs and the forced through IClick of KSlteiaittels through the evaporator always will switch on again * if the Obörfläohentemperatür by itself due to the nettirliohsü warming of the evaporator is total rose by dio hühero Vm ftbangetfiapdratur IUF above 0 ° 0, DAB bq the evaporator is defrosted * aimed When natural defrosting of the evaporator see consequently the length of the still »

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stand tent after the time required for natural defrosting. Under unfavorable circumstances, this period of time can become so long that the internal temperature of the: Hqrinalkühlfaohee to un ~ ::; permissible high values rise «Natural defrosting presents particular difficulties if the HOrmallcUhlfaob-TeraampXer is connected to a freezer compartment evaporator * which is connected to the normal refrigerator compartment evaporator via a constantly open connection pipe % \ · let» bo <3aB the refrigerant always flows through the two evaporators m, successively. The temperature of the Tiefy kÜhlfaoheB cannot be controlled by yourself, Instead, the refrigeration machine is kept on and off depending on the surface temperature of the fformalkühlfaoh evaporator. If it is too slow natural defrosting of the normal refrigerator compartment evaporator in this case the temperature of the cold-running cooler is impermissible high rise

Let "Ine object of the invention to avoid the aforementioned Haohteile and to accelerate the defrosting of norroalkühlfaoh evaporators." A particular aim of the invention is here, K is the defrosting capacity for nonoal refrigerator evaporators, which are naturally defrosted, however, it is also an aim of the invention to improve the defrosting conditions in SonraUcÜhlfaoh-Yördampfer, the duroh artificial heating, for example by elec ~ trisohe heating or the like, be defrosted.

The inventive method is characterized in that the evaporator after the start of each still

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the refrigeration machine is quickly emptied »by that at the beginning of the downtime in the evaporator duct ■ The liquid refrigerant located in the evaporator is collected in several siphon-like windings of a channel socket of the evaporator and from here through it by means of one on its input side. Evaporate overpressure generated by refrigerant from the outlet of the Evaporator is led out, at least with each from the lowest point of a siphon-like winding of the 2-channel coil of the evaporator channel to the next one HUhensohwelle from below to above displacement taking place The liquid these 'in the form of liquid locks forming Plüesigkeltspropfen is transported «

Duroh this procedure becomes the evaporator after beginning. each idle period of the lälltemasolaiBe faster than before of 'liquid Sällteaittel "cleans" nobei the emptying by pushing out the in the form of several PlusBigkeitsprofen collected liquid refrigerant through over pressure from the evaporator. Because several Liquid plugs are formed, among other things, the accumulation of the liquid and its emptying from the Evaporator accelerates,

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:, '■ "■: This procedure ensures, among other things, that at the beginning of every standstill only a very small amount of vaporization of liquid refrigerant can take place. Occurs at the beginning, it prevents the evaporator from heating up quickly.

To get the normal & ftlfaah vaporizer from liquid Discharge refrigerant near the start of each downtime.

The previous approach was to make the evaporator duct in a serpentine shape with a steady gradient so that at the beginning of a downtime in the liquid refrigerant located at the damper can flow evenly across the entire lungs of the channel coil near the bottom. whereby 3edοph constant evaporation and a corresponding cooling of the evaporator takes place »Bas outflow needs a lot of time because of the relatively long length of such a canal bottom, so that the canal snake of the Evaporator is emptied very slowly or, if the refrigerant flowing out is collected at the lowest point of the evaporator, not completely at all Emptying takes place. In both cases, defrosting is made considerably more difficult by the long-term vaporization of the liquid refrigerant.

In contrast, the method according to the invention wijfi the evaporator emptied very quickly, with the emptying practically completely by pushing out the collected liquid refrigerant in the form of Plüssigkeitspfrop-

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and only overlaid with a very small rope does not take place by evaporation of the refrigerant, The? e> steamer can heat up / correspondingly quickly · This has among other things the gate part »that the standstill strings 4 Chiller can be shorter and the temperature ^ konatana is improved in normal cold storage »when kept in rows of the KormalkUhlfachr-Terdampfers with fester TiefkiÜ3lfaob-Yerdampfer with constantly open connection line a good temperature constant of the Siefkühlfaohoe auoh achieved under unfavorable conditions, with only the temperature of the Hormalkuhlfaoh-Terdampfers or the normal cooling compartment by switching the refrigeration machine on and off needs to be regulated.

With natural defrosting of the Terdampfere As a result of the rapid warming, it was necessary to provide for relatively small structural sizes of normal-temperature compartment steamers * so far with HormalkOhlfaoh-Tdrdampfern. more natural Defrosting required to train them very large to deal with relatively high surface temperatures are sufficient To achieve cooling of the normal refrigerator compartment. .

The erfindungsgemäös method also Torteils at normal refrigerating compartment ireräampferr.v that duroh © by 'künstlich® Beheissung "swa example lölctrieche Behslsung or the like can be defrosted because that defrost more quickly and with geringerar heating capacity than previously carried out who" the scan.

The overdrive in
can sv / eolcsäßig auroh evaporation from after the start of the standstill line in $ m ? @ rdampf @ input from the istpil

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warm flue flowing into the refrigeration machine's lar pipe » A similar refrigerant is generated at least to a considerable extent. Such a stream of warm liquid Refrigerant occurs steadily for a short time after the compressor8 has come to a standstill, so that this effect occurs Rapid generation of the sum of pushing out the liquid plug required overpressure can be used.

the emergence of the overpressure Nooh besohleu- ^J nigt are intended or Terdampfereingang nioht ft to the capillary tube is connected, AUOH additionally or alone any other appropriate measures to increase or generation of überdruokes can be taken. For example, an inlet-side channel section of the evaporator channel, in which there is a small amount of fluid refrigerant, can be heated in order to evaporate this refrigerant to reduce the overrun. The heating can be carried out electrically or, if necessary, by means of a capillary tube which is in heat exchange connection with this channel section.

To carry out this novel process 1st

_fc a refrigerator or dergleiohen is provided, which has a normal refrigeration compartment, to which an upright evaporator of a refrigerating machine is assigned, which has a sole-length channel serving for the flow of the refrigerant and extending horizontally, whereby according to the invention it is provided that at least the duct sections of the siphon-like windings of the finnigen duct, which rise in the flow direction of the refrigerant, at an angle to the vertical

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run and with the upstream descending canal pieces are connected in tight arcs.

The inclined to the vertical rising channel pieces of the siphon-like windings ensure that the plugs of liquid that collect at their deepest points after the start of the standstill are pushed upwards by the overpressure _{9 so} that they prevent the overpressure from escaping upwards during the pushing up. Once the siphon-like winding in question is exceeded, the liquid in question either gets into the *; Exit of the evaporator or in a subsequent siphon-like winding. In the latter, it again forms a liquid spf, which, while maintaining its plug-shaped shape, is pushed ^{upwards over the following Böhensohwelle 1} by the excess pressure acting on it · '-ν- \' ·. · _ '.' ■■ _ ■ '

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It is important that every plug of liquid is present when it is pushed from bottom to top, it retains its plug-like shape, so that the one acting on it Difference pressure cannot equalize "

Due to the effect of the displacement of the liquid plug located closest to the inlet of the evaporator, the liquid plug located between it and the outlet, if any, are also underneath Compression of the swisohen the liquid plug located gas columns with shifted. *

The ascending analstüoke of the siphon-like

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Windings can expediently be inclined at an angle Ton 15 ° to 60 ° to the vertical. Their cross sections are of course meet as closely zn that the Plüssigkeitspfropfen leg upward strokes Verso retains its pfropfenähnliohe shape.

© 0 is particularly favorable if the snake-shaped® ea

nal has a maximum of three, preferably two siphon-length turns. * ■

Further features of the invention are in the following Description, the subclaims and the reference described or illustrated., Where e ~ it is understood that The invention in numerous other embodiments can be realized "

See in the drawing?

71g · 1 «domestic refrigerator in lengthwise

Son's side view, the normal TcUhIfa oh-Evaporate after the new Procedure is emptied,

Pig. 2 is an enlarged rear view of the In

Cooling compartment «, arranged evaporator of the refrigerator naoh pig. 1, where the vertical «Mohtung is marked with A. and cut a part of a pipe shown 1st,

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Fig. 5 shows an enlarged partial view through the Evaporator according to Pig, 2, seen along the section line III-III,

Fig. 4 a Sohemaskizae of the refrigeration machine dee Household refrigerated syrup according to Pig.1V

The household refrigerator shown in Pig, 1 is white; ^ a whole with 10 designated, heat-insulating. | Housing, inside of which a HormalMIblfach 11 and a freezer compartment 12 are arranged, which can be closed by separate doors 13, 14.

Daa Normalkühlfaoh 11 has two twin squares 15, 16 , and a Genrtieesohale 17 on ·

The KÜhluiag dee HonnalkUhlfaohss 11 takes place by means of

one lined up at a small distance from its rear wall arranged, e> in «n plate absorber 20, of ^ the in flg. 2 a rear row in an enlarged view is shown. In the freezer compartment 12 is a U-.

shaped sheet metal evaporator 21 arranged ». I.

In Pig, 4 let one, the same sketch of the except for the two Evaporator 20 and 21 in Pig. 1 ÖUteaafQhine this BaushaltskUhleohraakes not shown in detail. You Ealtemaeohlne has a compressor 22, a condenser 23, a capillary tube 24, the two means an etandig open connecting pipe 25 in series connected evaporators 20 and 21 and the suction line 26 leading back from the evaporator 21 and the compressor 22.

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The compressor 22 is used for! Temperature control of the normal ' 'Kühlfaohes by means of a conventional thermostat 27 duroh opening and closing of a switch 28 arranged in the electrical feed line 29 as a function of the sound of a temperature sensor 30 sensed surface temperature of the evaporator 20 on and off.

f In this preferred embodiment of the Verft is, dampers, defrosted 20 during each duroh the thermostat 27 effected standstill time of the compressor 22 and thus duroh natural during the standstill time of the refrigerator heating, ie without artificial heating * Diee carried out in the manner of the compressor DAFL 22 The evaporator 20 is switched on at a certain, preferably adjustable, surface temperature which is slightly above the freezing point of water and can be, for example, 3 ° to 4 °. After the compressor is switched on, the evaporator 20 is cooled by evaporation of the refrigerant that is then inevitably liquid, and then in turn cools the air in the normal refrigeration compartment 11. If Ψ is the perceived surface temperature of the evaporator 20 has reached a certain, preferably adjustable, low temperature value, e.g. - 10 ° 0 to - 20 ° 0 the compressor is automatically switched off by opening the switch 28 by means of the thermostat 27 and a new one Downtime of the refrigeration machine begins, which only occurs after complete defrosting of the evaporator 20 as described by switching on the compressor 22 again is terminated.

In the freezer. 12 * lower temperatures than in the Bormalkühlfaoh 11 are maintained, the awe ο Ic-

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moderate in general. -18 ⁰ C and even less. Since liquid refrigerant flows through the run-cooling compartment ^ vaporizer 21 only at the same time as * the NormaUcUhlfach-Yerdaiiipfer 20, a cooling capacity is dependent on the amount of downtime required for natural defrosting of the vaporizer, 20. Sufficient cooling of the freezer compartment assumes that the downtimes of the refrigeration machine are relatively short, even under unfavorable conditions, so that the freezer compartment cannot heat up excessively during periods of downtime of the refrigeration machine.

In order to achieve such rapid natural defrosting as a plate evaporator trained vaporizer ere * 20 su achieve, He.die explained in more detail with reference to Figures 2 and 3 Peculiarities on -

The one in Pig. The plate evaporator 20 shown in FIG. 2 is flat and made from two aluminum sheets joined together to form an evaporator channel 31. From the fork-shaped outlet 32 of the evaporator channel 31, the connecting pipe 25 inserted in this channel in a pressure-tight manner leads to the one in PIg. 1 shown freezer compartment evaporator 21. The capillary tube 24 is wound around this connecting tube 25 at der.Stelle 34 and then guided at 35 into the interior of the .Verbiudungsrohres 25 and. from here through the upper branch of the bifurcated output 32 by a narrow parts 35'abgedichtet therethrough in the ¹ input 36 of the evaporator channel 31 introduced, the capillary tube Auetrittsmündung wobßi shortly behind the narrow 35'befindet.

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The evaporator leading from entrance 36 to exit 32 " channel 31 has a relatively narrow input side Supply line kaiiRl 39, at 40 in the aickaaok-shaped winding channel 41, which extends in horizontal direction and in which] during the solitary time of the compressor mainly that of the cooling of the normal refrigerator compartment evaporation of the refrigerant takes place «

The sohlangenförmige channel 41 has two V-shaped siphon windings 43 »44, which via the sheet 46 to a" total W-shape are connected "The last in Ströraungsrichtung siphoriartlge winding 44 via a aoharfen _r narrow, upper arch 47 in an obliquely downward naoh aum & üb ~ 32 gang leader Kanalstüok. The two narrow, upper arches 46, 47 of the channel 41 form vertical waves for the upstream siphon-like winding 43 and 44 "

The two egg-shaped windings 43 and 44 are of the same design and each iron a straight, descending channel piece 49, 50 directed obliquely to the vertical A, and an ascending, straight one from the lowest point to the following threshold 46, 47 obliquely to the vertical Channel piece 51 »52 on. The lowest points of the siphpnsrtigen ^ convolutions 43, 44 forming the lower sheets 54, 55 are made as small · r as possible, so that even at very low J form Plüssigkeitssohlösser grafting forming liquids quickly after turning off the compressor at these locations ¹ Ullungsmengen which do not leave any glass bubbles in hindu and are therefore pushed by the upper pressure from the lower arches near the top in the direction of the exit "

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The cross-sectional shape of the evaporator channel 31 is semicircular according to FIG. 3. When using the. the commercial name "IPigen ¹¹ commercially available fluorocarbon refrigerant, the clear cross-section of the zlok-zag-shaped channel 41 can be, for example, approx for example, 0.1 may be om. This Zuleitungekanal 39 is so narrow "that can -verdampfen in him little refrigerant, and that the left in it after switching off the KompreaBors 22 .flüseige refrigerant rapidly by the pressure generated by nächströraendes liquid, warm refrigerant pressure In Sorm, liquid plugs filling its cross-section are pressed into the sole-length canal 4t.

This evaporator is designed in such a way that when the compressor is switched on it contains only a little liquid refrigerant and that, after the compressor has been shut down, the liquid refrigerant is automatically emptied roughly and intensively. For this purpose only awei sipüo ^ -like turns 43, 44 are provided * furthermore, the lower arches 54, b are made as tight as possible , so that in this embodiment, auralontal, short "connecting pieces between the descending and ascending duct sections are so Course as possible are also the inclined canal statues 51, 52 inclined ^ to the tertiary A. In this example, their inclination to the vertical is or the like. 20 °. $ 0 ° inclined.

The leigung and QuerDOhnitt the f4ns ^ eig9näeiß Kanalsttloke 51, 52 is in each case to be taken as m> ^ that the AOH the

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Switching off the compressor 22 from the lower arches 54-, from liquid rising in them their form as a retains a liquid plug that forms a liquid lock.

Daroli the illustrated and described training of the After each time the compressor and thus the refrigeration machine are switched off, the evaporator 20 is at the beginning of the The cold furnace in the evaporation channel comes to a standstill 41 liquid refrigerants located in rapid and practical. completely from the 7er stampf ericanal 41 in the-zum Tieikiüalfaoh · Evaporator 21 leading connecting line 25 shifted automatically, namely duroh the upper pressure caused by the after switching off the evaporator from the KapiHarrohr 24 flowing into the inlet 36 of the evaporator channel 41, warm, liquid refrigerant is produced. What is essential here is ηοoh that an escape of the developing Overdrain as a result of the forming plugs of liquid y is prevented, so that the liquid in the evaporator is practically great duroh the overpressure in the connecting line 25 is pressed and enters the freezer compartment evaporator 21.

It goes without saying that the individual PIUbaigteitspropfen do not consist of pure liquid, but rather lioh there are also vapor bubbles in them or during the transportes can form.

The descending Kanalatüoke of the siphon-like coils of the In some cases, the evaporator 20 can advantageously also be arranged vertically instead of the illustrated arrangement inclined to the vertical, in which case the

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Lowing channel pieces can be appropriately more inclined to the vertical.

In a variant of the ITormalkühlfaah evaporator that is not shown, the clear cross-sections are descending Kanäletüoke of the siphon-like turns larger than that the rising canal sections of these turns.

The cross-sections of the descending channel pieces of the serpentine channel can expediently be so large that the ! Plugs of liquid do not open when flowing down- f solve * In some columns the cross-sections of the descending canal pieces can also be made so that The liquid plugs transported over the previous siphon dissolve as it flows downwards and the liquid only turns into a liquid plug again at the deepest point of the relevant siphon-like winding accumulates

Be the illustrated example where the Horualkühlfaoh evaporator 20 a Siefkühlfaoh terdampfer 21 The main thing is that the refrigerant is siphoned out in a liquid state Emptying of the HormalkUhlfaoh-Yerdampfers also the previous j part that this pushed out refrigerant arrives in the Ti © fkühlfaoh-Terdampfer in a liquid state and therefore does not have to be condensed. through which the XlefkUhlfach-Terdampfer would be heated

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Claims (1)

- 16 - Petentan review 1./Method for accelerating the defrosting of a normal cooling faoh evaporator of a refrigerator or the like of liquid refrigerant during the downtimes of the refrigeration machine brought about for temperature control, daduroh characterized in that the evaporator empties quickly after the start of each downtime of the refrigeration machine is "by the liquid refrigerant in the evaporator channel of the evaporator in several siphon-like windings of a channel" · coil of the evaporator is collected and duroh by moving it by means of a on its inlet Evaporation of refrigerant sucks in overpressures β from the Exit of the evaporator is led out. Whereby at least at each of the deepest point a siphon-like Winding of the channel sole length of the evaporator channel to the subsequent height threshold from bottom to top taking place Displacement of the fluidity this is transported in the form of liquid looseners forming jftigkeltspfropfen. · *. 2. The method according to claim 1, characterized in that at least a considerable rope of the overpressure due to evaporation from after the start of the downtime into the evaporator inlet warm refrigerant flowing in from the capillary tube of the refrigeration machine. 3. The method according to claim 1 or 2, characterized daduroh, defl the evaporator during every downtime -17 * 109837/0638 2Ö06469 2367 - 17 - ■ '■■ the refrigeration machine is only defrosted by natural warming and the refrigeration machine only after completed »defrosting is switched on again. 4. Refrigerator or the like that has a normal freezer compartment has, the one arranged in the upright position Evaporator is assigned to a refrigeration machine, which is used to flow through the refrigerant Has serpentine channel, which extends in the horizontal direction, for implementation dee. Method according to one of the preceding claims, jj characterized in that at least the flow I direction of the refrigerant rising channel pieces (5 ^ t 52) of the siphon-like windings (43,44) of the The serpentine channel (41) of the evaporator (20) runs obliquely only vertically and is narrow with the upstream, descending channel pieces (49, 50) Arcs (54V 55) are connected 5. Refrigerator according to claim 4, characterized in that that there is a rising piece of canal (51 »52) under one Is inclined at an angle of 15 ° to 50 ° to the vertical (A), 6 · Refrigerator according to claim 4 or 5 »characterized by | net that the serpentine channel (41) has a maximum of three, preferably two siphon-like turns (43, 44). _v ■ ■ - »- ■ '_ . · ^: _Λ .- ■ '■ "' 7. Refrigerator according to one of Claims 4 to 6, characterized in that at least one descending channel section of the egg-shaped valleys obliquely to the vertex 109837/0638. _1Q .. «18 - a-12 8. Refrigerator naoh one of claims 4 to 7 »thereby characterized in that at least one descending duct section d «: c siphon-like turns perpendicular Runs. 9. Refrigerator according to one of claims 4 to 7, characterized in that the siphon-like winding (43 <44) has a V -shaped shape. 10. Refrigerator naoh one of claims 4 to 9, thereby characterized in that the evaporator (20) is connected to the capillary tube (24) of the refrigerating machine. 11. Refrigerator naoh one of claims 4 to 10, thereby characterized in that the rising channel piece has at least one siphon-like turn a smaller one Has higher Quersohnltt than the descending Kanalatüok 12. Refrigerator naoh one of claims 4 to 11, thereby characterized in that the evaporator (20) is a "! plate evaporator. 13. Eühlaohranlc according to one of claims 4 to 12, characterized characterized in that the output of the evaporator (20) of the normal refrigerator compartment in series with the input of a an evaporator (21) associated with a freezer compartment of the same Refrigeration machine via a connecting pipe that is always open (25) is connected * 109837/0638 Lee on the back