U.S. patent application number 10/517347 was filed with the patent office on 2005-10-20 for refrigerant circuit and a refrigerating system.
This patent application is currently assigned to BEHR GmbH & CO. KG. Invention is credited to Burk, Roland, Geskes, Peter, Pfender, Conrad.
Application Number | 20050229629 10/517347 |
Document ID | / |
Family ID | 32519016 |
Filed Date | 2005-10-20 |
United States Patent
Application |
20050229629 |
Kind Code |
A1 |
Burk, Roland ; et
al. |
October 20, 2005 |
Refrigerant circuit and a refrigerating system
Abstract
The invention relates to a refrigerant circuit comprising at
least one heat absorption element and at least one heat dissipation
element. According to the invention, heat transfer elements
carrying out the same function can be operational in the
refrigerant circuit at different pressure levels of the refrigerant
A refrigerating system provided with the inventive refrigerant
circuit is also disclosed.
Inventors: |
Burk, Roland; (Stuttgart,
DE) ; Geskes, Peter; (Stuttgart, DE) ;
Pfender, Conrad; (Besigheim, DE) |
Correspondence
Address: |
FOLEY AND LARDNER
SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
BEHR GmbH & CO. KG
|
Family ID: |
32519016 |
Appl. No.: |
10/517347 |
Filed: |
December 9, 2004 |
PCT Filed: |
December 15, 2003 |
PCT NO: |
PCT/EP03/14232 |
Current U.S.
Class: |
62/498 ;
62/500 |
Current CPC
Class: |
B60H 2001/00949
20130101; B60H 2001/00928 20130101; B60H 1/00921 20130101; F25B
6/00 20130101; F25B 2339/0444 20130101; F25B 2500/01 20130101; B60H
2001/3298 20130101; B60H 1/00885 20130101; F25B 6/04 20130101; F25B
2339/0445 20130101; B60H 1/00878 20130101; F25B 2341/0012 20130101;
F25B 5/00 20130101; F25B 2341/0014 20130101 |
Class at
Publication: |
062/498 ;
062/500 |
International
Class: |
F25B 001/00; F25B
001/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 16, 2002 |
DE |
102 58 966.6 |
Claims
1. A refrigerant circuit with at least one heat receiver and with
at least one heat emitter, characterized in that a plurality of
functionally identical heat exchangers can be operated
simultaneously at a different refrigerant pressure.
2. The refrigerant circuit as claimed in claim 1, characterized in
that each refrigerant connection between two heat exchangers
operable at a different pressure contains at least one compression
element and/or at least one expansion element.
3. The refrigerant circuit as claimed in claim 2, characterized in
that at least one compression element and/or at least one expansion
element forms with a heat exchanger a structural unit.
4. The refrigerant circuit as claimed in claim 1, characterized in
that a first heat receiver, a second heat receiver and a heat
emitter can be operated at three different pressure levels.
5. The refrigerant circuit as claimed in claim 1, characterized in
that a first heat receiver and a heat emitter can be operated at a
common or similar pressure level.
6. The refrigerant circuit as claimed in claim 5, characterized in
that a compensation element, in which, in particular, the
refrigerant can be filtered and/or water can be extracted from the
refrigerant, is arranged downstream of the first heat receiver.
7. The refrigerant circuit as claimed in claim 5, characterized in
that the first heat receiver is arranged hydraulically between two
portions of the heat emitter.
8. The refrigerant circuit as claimed in claim 7, characterized in
that the two portions communicate with one another via a bypass
connection, the bypass connection comprising, in particular, a
third portion of the heat emitter.
9. The refrigerant circuit as claimed in claim 5, characterized in
that the first heat receiver forms, with a portion of the heat
emitter, a closed subcircuit, in particular within one pressure
level.
10. The refrigerant circuit as claimed in claim 9, characterized in
that the first heat receiver is arranged so as to be geodetically
lower than the heat emitter portion.
11. The refrigerant circuit as claimed in claim 9, characterized in
that the first heat receiver communicates with a main circuit via a
suck-off element, the suck-off element, in particular, being
integratable into a heat emitter.
12. The refrigerant circuit as claimed in claim 1, characterized in
that at least one heat receiver forms, with at least one heat
emitter, a structural unit.
13. The refrigerant circuit as claimed in claim 1, characterized in
that at least one heat receiver can additionally be cooled, in
particular by means of air flowing past.
14. The refrigerant circuit as claimed in claim 1, characterized in
that heat energy from a secondary circuit, in particular a cooling
circuit, can be received by at least one heat receiver.
15. The refrigerant circuit as claimed in claim 1, characterized in
that a first heat receiver is a cooler for electronic components,
and, in particular, a second heat receiver is a cold generator of
an air conditioning system.
16. A refrigerating system, in particular an air conditioning
system for a motor vehicle, with a refrigerant circuit which is
designed as claimed in claim 1.
Description
[0001] The invention relates to a refrigerant circuit with heat
receivers and with heat emitters and to a refrigerating system with
a refrigerant circuit.
[0002] Refrigerant circuits of this type are used in refrigerating
systems, such as, for example, air conditioning systems, in order
to transport heat from at least one first spatial region into at
least one second spatial region, in particular with a temperature
level equal to or higher than that of the first spatial region. The
refrigerant in this case receives heat in a heat exchanger,
operated as a heat receiver, in the first spatial region, and is
conducted to a heat exchanger, operated as a heat emitter, in the
second spatial region, in order to emit heat there.
[0003] In order to allow the transport of heat from a relatively
colder to a relatively warmer spatial region, the refrigerant is
conventionally conducted in an expanded state, that is to say at a
lowered temperature, through the heat receiver and in a compressed
state, that is to say at an increased temperature, through the heat
emitter. For this purpose, the refrigerant circuit comprises a
compression element, such as, for example, a compressor, and an
expansion element, such as, for example, an expansion valve, so
that the refrigerant flows through the circuit in the sequence:
compression element--heat emitter--expansion element--heat
receiver.
[0004] Condensers, in which the refrigerant condenses, with heat
energy being emitted, are often used as heat emitters, the
temperature of the refrigerant changing only insignificantly during
the condensation phase transition. Similarly, what are known as
refrigerant evaporators, in which the refrigerant is evaporated,
are frequently used as heat receivers, the temperature of the
refrigerant likewise changing only insignificantly during the
evaporation phase transition. However, since refrigerant circuits
are sometimes also operated without phase transitions of the
refrigerant, the terms "condenser" and "evaporator" are, in part,
misleading and, apart from special examples, will not be used
here.
[0005] In the case of a given refrigerant, the temperature levels
of a refrigerant circuit depend mainly on the pressure levels,
basically higher temperatures prevailing on the high-pressure side
of the circuit, that is to say in the direction of flow of the
refrigerant downstream of the compression element, than on the
low-pressure side downstream of the expansion element. If, then, a
plurality of heat receivers are to be used in a refrigerant
circuit, the pressure conditions on the low-pressure side of the
circuit have to be adapted to the heat receiver having the lowest
desired operating temperature, since, at higher temperatures, this
heat receiver could not receive sufficient heat energy. If, in the
case of a further heat receiver, a higher temperature is desired or
is sufficient, it is thermodynamically inefficient to operate this
further heat receiver at a low temperature. The corresponding
consideration also applies in a similar way to heat emitters.
[0006] The object of the invention is, therefore, to provide a
refrigerant circuit and/or a refrigerating system, in which a
plurality of heat receivers and/or a plurality of heat emitters can
be operated in each case at different temperatures.
[0007] This object is achieved by means of a refrigerant circuit
having the features of claim 1 and by means of a refrigerating
system having the features of claim 16.
[0008] According to claim 1, a refrigerant circuit has at least one
heat receiver, in which heat can be received from a refrigerant,
and at least one heat emitter, in which heat can be emitted by the
refrigerant. The object of the invention is advantageously achieved
in that a plurality of functionally identical heat exchangers, that
is to say a plurality of heat receivers or a plurality of heat
emitters, can be operated at a different refrigerant pressure. As a
result, the basic idea of the invention, to be precise to adapt the
operating temperatures of a plurality of functionally identical
heat exchangers to different requirements, can be implemented in a
simple way.
[0009] Within the scope of the present invention, those heat
exchangers are to be considered as functionally identical heat
exchangers which, while the refrigerant circuit is in operation,
simultaneously fulfill the same function, that is to say either a
heat transfer from a medium to the refrigerant or from the
refrigerant to a medium. What may be considered as a medium in this
case is, for example, a liquid, gaseous, supercritical or any other
fluid, just as well as, for example, a solid or an in particular
heat-generating device or even combinations of these. The
functional identity of two heat exchangers is not affected by
possibly different functions, which two or more heat exchangers
fulfill at different time points, for example in different
operating modes of the refrigerant circuit.
[0010] Within the scope of the present invention, two refrigerant
pressure levels are different from one another when the difference
between the pressure amounts of the individual levels is greater
than a pressure drop which normally occurs, for example, along
refrigerant lines or heat exchangers. In particular, two heat
exchangers directly connected in series hydraulically cannot be
operated at different refrigerant pressure levels, insofar as no
conveying or throttling means for the refrigerant are provided in
or between the two heat exchangers. By contrast, a pressure
difference caused by a compression element or by an expansion
element is highly suitable for generating two different refrigerant
pressure levels within the scope of the invention.
[0011] What is designated as a compression element is any device
which is suitable for conveying refrigerant from one location of a
circuit to another location of the circuit having a higher
pressure, that is to say for the compression of refrigerant.
Compressors and pumps are examples of compression elements.
[0012] What is designated as an expansion element is any device
which is suitable for generating a pressure drop between one
location of a refrigerant circuit and another location of the
circuit, that is to say for the expansion of refrigerant.
Externally activatable and nonactivatable expansion valves and also
throttles are examples of expansion elements, any contraction in
the refrigerant circuit, for example a tube of small diameter
between two heat exchangers, being suitable, where appropriate, as
a throttle. Under some circumstances, a flow diameter reduced to
half is sufficient for a desired contraction, that is to say a
contraction which is suitable in this sense as a throttle.
[0013] In order to achieve a compact type of construction, it is
advantageous to combine a compression element and/or an expansion
element structurally with a heat exchanger. For example, a throttle
can be integrated into a heat exchanger in a simple way. If a heat
exchanger has a plurality of flow paths connected in series
hydraulically, then a throttle integrated into the heat exchanger
can also be implemented by means of a reduced number of flow ducts
which, in particular, form the first or last flow path of the heat
exchanger and are hydraulically parallel to one another.
[0014] According to an advantageous refinement, a first heat
receiver, a second heat receiver and a heat emitter can be operated
at three different pressure levels, the first heat receiver being
operable at a higher pressure than the second heat receiver. This
ensures two different cooling temperature levels, with a heat
emission temperature independent of these. In particular the first
and the second heat receivers are connected hydraulically in
parallel, each of the two heat receivers being preceded and/or
followed by its own expansion element, so that the heat receivers
can be acted upon with refrigerant at different pressure levels.
Under some circumstances, it is sufficient if only the first or
only the second heat receiver is preceded or followed by an
expansion element. In another version, a first and a second heat
receiver are connected hydraulically in series, in which case a
pressure difference can be implemented by means of an interposed
expansion element.
[0015] According to a preferred embodiment, a first heat receiver
and a heat emitter can be operated at a common pressure level. This
avoids the need for additional compression and/or expansion
elements and for a resulting outlay in terms of manufacture, of
assembly and of cost. The operating temperature of the first heat
receiver corresponds at least approximately to the operating
temperature of the heat emitter.
[0016] Particularly preferably, a compensation element for the
refrigerant, such as, for example, a collecting container, in
which, if appropriate, a filter element and/or a drier can be
received, is arranged downstream of the first heat receiver. The
compensation element is in this case constructed essentially in the
same way as a compensation element conventionally following a heat
emitter and serves for the collection and, if appropriate, phase
separation of the refrigerant, so that only liquid refrigerant is
supplied to an expansion element.
[0017] According to a preferred development of the refrigerant
circuit, the first heat receiver is arranged hydraulically between
two portions of the heat emitter. This means that refrigerant,
after flowing through a first portion of the heat emitter, is
conducted through the first heat receiver and is subsequently
returned into the heat emitter where it flows thereafter through a
second portion.
[0018] In one embodiment, the entire refrigerant stream is in this
case routed through the first heat receiver. In a further version,
only part of the refrigerant stream is routed through the first
heat receiver, while another part of the refrigerant stream is
conducted through a bypass connection from the first to the second
portion of the heat emitter. Particularly preferably, the bypass
connection comprises a third portion of the heat emitter, so that,
after the first portion, the refrigerant flows either through the
first heat receiver or the third portion of the heat emitter and,
finally, through the second portion.
[0019] According to a preferred refinement, the first heat receiver
forms, with a portion of the heat emitter, a closed subcircuit. The
refrigerant is then extracted from a main circuit, downstream of
the heat emitter portion, routed through the first heat receiver
and supplied to the main circuit again, upstream of the heat
emitter portion. In particular, the subcircuit contains a
compression element and an expansion element, for example the
compression element also serving as a compression element of the
main circuit. Preferably, however, the closed subcircuit is located
within a pressure level, that is to say no compression or expansion
elements are contained in the subcircuit.
[0020] According to an advantageous development, the first heat
receiver is arranged so as to be geodetically lower than the heat
emitter portion of the subcircuit. Refrigerant which receives heat
in the first heat receiver, that is to say is heated, rises upward
and enters the heat emitter portion, in order to emit heat there,
that is to say be cooled, and to fall downward again to the first
heat receiver. No compression element is required for such a
natural circulation, as it is known, and therefore this heat
transport takes place even when a compression element is either
switched off or is not present at all. Under some circumstances,
therefore, heating or cooling may be carried out with an energy
saving. In order to assist the natural circulation with regard to a
flow resistance of the subcircuit, particularly preferably an
additional refrigerant conveying device, such as, for example, a
liquid pump, is provided, by means of which a pressure drop along
the refrigerant subcircuit can be compensated.
[0021] Another advantageous development makes use, to maintain a
refrigerant stream in the subcircuit, of a suck-off element, via
which the first heat receiver communicates with the main circuit.
The suck-off element, which is designed, for example, as what is
known as a Venturi tube or the like, in this case sucks off
refrigerant from the first heat receiver and supplies it to the
main circuit. A pressure drop along the refrigerant subcircuit is
thereby likewise compensated or overcompensated. The suck-off
element can advantageously be integrated into a heat emitter.
[0022] According to a preferred embodiment of the refrigerant
circuit according to the invention, at least one heat receiver
forms, with at least one heat emitter, a structural unit.
Particularly in the case of identical or similar refrigerant
pressure levels, and consequently identical or similar operating
temperature levels, simplified mounting in a predetermined
construction space can be implemented by means of such a combined
component.
[0023] According to a further embodiment, at least one heat
receiver can additionally be cooled. This means that only part of
the heat energy received is transferred to the refrigerant and
transported away and part is emitted directly to a cooling medium,
such as, for example, air flowing past.
[0024] According to an advantageous embodiment, heat energy from a
medium of a secondary circuit is received by at least one heat
receiver which, particularly in the case of a higher refrigerant
pressure, can be operated as at least one further heat receiver,
the secondary circuit being particularly preferably a cooling
circuit. Indirect cooling of one or more heat-generating components
thereby becomes possible.
[0025] According to a preferred version, a first heat receiver is
designed as a cooler for electronic components. Particularly
preferably, a second heat receiver is designed as cold generator of
an air conditioning system, in particular for motor vehicles. The
idea of the invention becomes noticeable particularly clearly here,
since cold generators of air conditioning systems are
conventionally operated at markedly lower temperatures than coolers
of electronic components. It is therefore particularly
advantageous, in this case, to operate two heat receivers at
different pressure levels.
[0026] According to a preferred development, the refrigerant
circuit according to the invention is inserted into a refrigerating
system, in order to cool or to heat a plurality of components at
different temperature levels.
[0027] The invention is explained in more detail below by means of
exemplary embodiments, with reference to the drawings in which:
[0028] FIG. 1 shows a diagrammatic view of a refrigerant circuit
according to the present invention,
[0029] FIGS. 2-8 show in each case a diagrammatic view of a
refrigerant circuit, and
[0030] FIG. 9 shows a diagrammatic view of a secondary circuit.
[0031] FIG. 1 illustrates a diagrammatic view of a refrigerant
circuit 10. A compression element 20 and an expansion element 30
delimit a high-pressure side 40 and a low-pressure side 50 of the
circuit 10. Consequently, starting from the compression element 20,
the refrigerant flows counterclockwise through the circuit 10. As a
result of compression in the compression element 20, which is
designed, for example, as a compressor, the temperature of the
refrigerant increases, whereupon heat from the refrigerant is
emitted in a heat emitter 60 to air, indicated by arrows 70, which
is flowing past.
[0032] The refrigerant subsequently flows through a first heat
receiver 80, in which it receives heat from a component to be
cooled, not shown, such as, for example, an electronic control
device or the like. The refrigerant is thereafter intercepted in a
compensating or collecting container 90 and supplied to the
expansion element 30 where it enters the low-pressure side 50.
[0033] As a result of expansion in the expansion element, the
temperature of the refrigerant decreases markedly, so that, in a
second heat receiver 100, a further component, not illustrated,
such as, for example, an air stream or the like, can be cooled,
with heat energy being received. The cooling temperature of the
component cooled by the heat receiver 100 located on the
low-pressure side is in this case markedly lower than the cooling
temperature of the component cooled by the heat receiver 80 located
on the high-pressure side, since the heat receiver can be operated
at the pressure level of the heat emitter. By the refrigerant being
conducted further on to the compression element 20, the refrigerant
circuit 10 is closed.
[0034] If the refrigerant circuit 10 is operated with a two-phase
refrigerant, such as, for example, R134a, the difference in the
temperature levels on the high-pressure side 40 and on the
low-pressure side 50 is particularly pronounced. In a design of the
circuit 10 for conventional air conditioning systems, the
temperature of the two-phase range of the refrigerant is, as a
rule, in the region of 40.degree. C. to 70.degree. C. on the
high-pressure side, but in the region of 0.degree. C. on the
low-pressure side. The heat receiver 100, then operated as an
evaporator, on the low-pressure side is suitable for the cooling of
air for the air conditioning of a space, for example of an interior
of a motor vehicle, and the heat receiver 80 on the high-pressure
side is adapted to a preferred cooling temperature of electronic
components, such as control units and the like. The refrigerant
expanded in the expansion element 30 is therefore evaporated in the
evaporator 100, compressed in the compressor 20, condensed in the
heat emitter 60, then active as a condenser, at least partially
evaporated again and/or heated in the heat receiver 80 and,
finally, intercepted in the compensating element 90 where the
gaseous fraction is separated.
[0035] FIG. 2 shows a refrigerant circuit 110 with a compression
element 120, a heat emitter 130, a first heat receiver 140, a
compensating element 150, an expansion element 160 and a second
heat receiver 170. Here, refrigerant flows through a first portion
180 of the heat emitter 130, subsequently through the first heat
receiver 170 and thereafter through a second portion 190 of the
heat emitter 130. The entire refrigerant in this case flows through
the first heat receiver 170.
[0036] If the desired cooling temperature of the first heat
receiver 140 is lower than the operating temperature of the heat
emitter 130, the pressure level of the first heat receiver and
consequently also of the second portion 190 of the heat emitter 130
is lowered, if appropriate, with the aid of an expansion element
200. In the simplest instance, the expansion element 200 is formed
as a throttle by means of a small orifice through which the
refrigerant must pass, in which case the orifice may be arranged,
for example, in a partition of a collecting box of the heat emitter
130. In the case of a heat emitter with heat exchanger tubes
interconnected in a serpentine-like manner, it is possible to
implement the throttle action by means of a reduced number of tubes
or ducts of multichamber tubes, that is to say by means of a
reduced flow cross section, in a serpentine segment, in particular
in the last serpentine segment of the first heat emitter portion
180. It is likewise possible to use an externally controllable
expansion valve as an expansion element 200, with the result that
the operating temperature of the first heat receiver 140 can be
adapted to requirements varying in time.
[0037] In a similar exemplary embodiment, which is not pictured,
the compensating element, for example designed as a collecting
container and, if appropriate, equipped with a filter unit and/or
drier unit, forms, with the heat emitter, a structural unit, the
refrigerant, after flowing through the compensating element, being
routed through what is known as a supercooling portion of the heat
emitter. This variation, which is also basically possible in the
other exemplary embodiments listed, without departing from the
scope of the present invention, makes it possible here to connect
the first heat receiver and the compensating element in succession,
so that the second portion 190 of the heat emitter 130 from the
preceding example (FIG. 2) forms the supercooling portion of the
unit consisting of heat emitter and of compensating element.
[0038] In the refrigerant circuit 210 in FIG. 3, a first heat
receiver 220 is covered by only one part 230 of the refrigerant
stream, whereas another part 240 of the refrigerant stream flows
through a third portion 250 of the heat emitter 260, the third
portion 250 being arranged between a first portion 270 and a second
portion 280 of the heat emitter 260. Refrigerant coming from the
compression element 290 therefore flows through the first portion
270 of the heat emitter 260, is then apportioned to the third
portion 250 and the first heat receiver 220 and is subsequently
combined again in the third portion 280 of the heat emitter 260.
The refrigerant is subsequently again intercepted in a compensating
element 300, so that, if appropriate, a gaseous fraction of the
refrigerant can be separated.
[0039] The refrigerant circuit 310 in FIG. 4 differs from the
circuit 210 known from FIG. 3 basically in that the first heat
receiver 320 is arranged so as to be geodetically lower than the
heat emitter 360, in particular than its middle portion 350 with
which the first heat receiver forms a closed subcircuit. As a
result, as illustrated in the refrigerant circuit 410 in FIG. 5,
heat transport from the first heat receiver 420 to the heat emitter
460 or the middle portion 450 of the latter becomes possible, even
with the compression element 490 switched off.
[0040] Such natural circulation cooling proceeds automatically,
since the refrigerant is heated and/or, if appropriate, partially
evaporated as a result of heat being received in the first heat
receiver 420, rises upward and is cooled again and/or, if
appropriate, condensed in the middle portion 450 of the heat
emitter 460, after which the refrigerant falls again and arrives at
the first heat receiver. The transported heat energy is in this
case emitted, for example, to an airstream 470. A cooling action of
the first heat receiver 420 is thus maintained, even with the
compression element 490 switched off, as, for example, when an air
conditioning system is operated in winter. The associated saving of
energy is in this case obvious. As compared with operation of the
refrigerant circuit 310 (FIG. 4) in summer, with the compression
element 390 switched on, however, the direction of flow of the
refrigerant through the first heat receiver 420 has been
reversed.
[0041] In a further exemplary embodiment, not shown, the natural
circulation is assisted by a small refrigerant conveying device,
such as, for example, a liquid pump, in which case the refrigerant
conveying device may be arranged either upstream or downstream of
the first heat receiver.
[0042] FIG. 6 illustrates a further refrigerant circuit 510 with a
heat emitter 540 consisting of a first portion 520 and of a second
portion 530, in which refrigerant circuit a first heat receiver 550
forms, with the second portion 530 of the heat emitter 540, a
closed circuit. In order to promote a return of the refrigerant
from the first heat receiver 550, the first heat receiver 550
communicates with the heat emitter 540 via a suck-off element 560,
the suck-off element 560 being designed, for example, as what is
known as a Venturi tube, in which the pressure in the line 570
coming from the first heat receiver 550 is lowered within the heat
emitter 540 by means of refrigerant flowing past.
[0043] FIG. 7 shows a refrigerant circuit 610 with a suck-off
element 660. In contrast to the circuit 510 in FIG. 6, in which the
suck-off element 560 is integrated into the heat emitter 540
between the two portions 520 and 530, the suck-off element 660 is
arranged between the compression element 680 and the heat emitter
640. As in FIG. 6, the direction of flow of the refrigerant is also
indicated in FIG. 7 by arrows.
[0044] FIG. 8 illustrates, as a further variant, a refrigerant
circuit 710, in which a high-pressure side 720 and a low-pressure
side 730 are separated from one another by a compression element
740 and two expansion elements 750, 760. A subcircuit 800 formed by
a first heat receiver 770 and a portion 780 of a heat emitter 790
extends in this case onto both sides 720, 730. In the subcircuit
800, the refrigerant is discharged from the first heat receiver 770
by means of the expansion element 750, designed, for example, as a
throttle, into the low-pressure side 730, in order, finally, to be
compressed by the compression element 740 and supplied to the heat
emitter 790. In the heat emitter 790, the refrigerant is
apportioned to the subcircuit 800 and a main circuit 810 of the
refrigerant circuit 710. A second portion 820 of the heat emitter
790, a compensating element 830, the expansion element 760 and a
second heat receiver 840 on the lower-pressure side 730 are located
in the main circuit 810.
[0045] In a similar exemplary embodiment, a further expansion
element is located in the subcircuit 800 within the heat emitter
790 and the first heat receiver 770, so that the pressure and/or
the temperature of the heat receiver 770 can, if necessary, be
brought to a reduced level, as compared with the heat emitter
790.
[0046] In another exemplary embodiment, the second portion 820 of
the heat emitter 790 is dispensed with, so that the vanishing-off
point of the subcircuit 800 from the main circuit 810 is arranged
hydraulically between the heat emitter 790 and the expansion
element 760 and upstream or downstream of the compensating element
830.
[0047] FIG. 9 illustrates a detail of a refrigerant circuit 910
according to the present invention. A heat receiver 920 is arranged
on a high-pressure side of the refrigerant circuit 910 in order to
receive heat energy from a secondary cooling circuit 930. The
secondary cooling circuit 930 serves in this case for heat
transport from a plurality of components 940, 950 and 960 connected
in series with or in parallel to one another to the heat exchanger
920 which, in terms of the cooling circuit 930, is a heat emitter.
Coolant circulation through the cooling circuit 930 is ensured by a
compression element 970 which is designed, for example, as coolant
pump. The components 940, 950 and 960 to be cooled are, for
example, electronic subassemblies or controls or other
heat-generating devices.
* * * * *