U.S. patent application number 09/836787 was filed with the patent office on 2001-12-27 for charged internal combustion engine.
Invention is credited to Hoecker, Patric, Jaisle, Jens-Wolf, Munz, Stefan.
Application Number | 20010054287 09/836787 |
Document ID | / |
Family ID | 7641615 |
Filed Date | 2001-12-27 |
United States Patent
Application |
20010054287 |
Kind Code |
A1 |
Hoecker, Patric ; et
al. |
December 27, 2001 |
Charged internal combustion engine
Abstract
The invention concerns a charged internal combustion engine with
at least one stage of charging by a turbocharger. The invention is
characterized by the fact that at least one supplemental compressor
is connected parallel to or in series with the turbocharger, where
the supplemental compressor has a drive independent form the
working medium cycle of the internal combustion engine.
Inventors: |
Hoecker, Patric;
(Landau/Pfalz, DE) ; Munz, Stefan; (Ludwigshafen,
DE) ; Jaisle, Jens-Wolf; (Heidelberg, DE) |
Correspondence
Address: |
BorgWarner Inc.
Attn: Patent Docket Administrator - Patent Dept.
3001 W. Big Beaver Road, Ste. 200
P.O. Box 5060
Troy
MI
48007-5060
US
|
Family ID: |
7641615 |
Appl. No.: |
09/836787 |
Filed: |
April 17, 2001 |
Current U.S.
Class: |
60/612 ; 123/562;
123/564; 60/602 |
Current CPC
Class: |
Y02T 10/12 20130101;
F01N 3/32 20130101; F02M 26/08 20160201; F02B 37/04 20130101; F02B
29/0406 20130101; F02M 26/16 20160201; F02B 37/18 20130101; F02B
39/10 20130101 |
Class at
Publication: |
60/612 ; 60/602;
123/562; 123/564 |
International
Class: |
F02B 033/44; F02D
023/00; F02B 033/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 11, 2000 |
DE |
100 23 022.9 |
Claims
1. Charged Internal Combustion Engine 1.1 with at least one-step
charging by a turbocharger, 1.2 identified by the fact that at
least one supplemental compressor is connected to the turbocharger
parallel or in series; 1.3 the supplemental compressor has a drive
independent from the working medium cycle of the internal
combustion engine.
2. Internal combustion engine based on claim 1, identified by the
fact that the additional compressor is powered by an electric
motor.
3. Internal combustion engine based on claim 1 or 2, identified by
the fact that the supplemental compressor is arranged in front of
the turbocharger in the flow direction.
4. Internal combustion engine based on one of the claims 1 to 3,
identified by the fact that there is at least one closing or
switching means between the supplemental compressor and the
turbocharger.
5. Internal combustion engine based on one of the claims 1 to 4,
identified by the fact that the turbocharger has a charge cooler
attached behind it, or with multi-level charging, at least one
charge cooler is connected behind one level.
6. Internal combustion engine based on one of the claims 1 to 5,
identified by the fact that the turbocharger has a charge cooler
attached behind it, or with multi-level charging, at least one
charge cooler is connected behind one level.
7. Internal combustion engine based on one of the claims 1 to 6,
identified by the fact that the supplemental compressor is used as
a secondary air pump to draw air in a catalytic converter.
8. Internal combustion engine based on one of the claims 1 to 7,
identified by the fact that an electric engine which provides power
to the supplemental compressor is present.
9. Internal combustion engine based on one of the claims 1 to 8,
identified by the fact that an electronic control device is present
to power the supplemental compressor and the closing or switching
means.
10. Internal combustion engine based on one of the claims 1 to 9,
identified by the fact that the supplemental compressor aids the
turbocharger in operational conditions in which the power taken
from the exhaust flow is insufficient.
11. Internal combustion engine based on one of the claims 1 to 10,
identified by the fact that the supplemental compressor is turned
off by the turbocharger when the required boost pressure is
attained.
12. Internal combustion engine based on one of the claims 1 to 10,
identified by the fact that the supplemental compressor is used to
deliberately increase the boost pressure.
13. Internal combustion engine based on one of the claims 1 to 12,
identified by the fact that the supplemental compressor and the
turbocharger draw from different intake areas.
14. Internal combustion engine based on one of the claims 1 to 12,
identified by the fact that the supplemental compressor and the
turbocharger draw from the same intake area.
15. Internal combustion engine based on one of the claims 1 to 14,
identified by the fact that the air compressed by the supplemental
compressor can only flow in the direction of the turbocharger.
16. Internal combustion engine based on one of the claims 1 to 15,
identified by the fact that the turbocharger no longer draws from
the supplemental compressor, once the supplemental compressor is
switched off.
17. Internal combustion engine based on one of the claims 1 to 16,
identified by the fact that there is at least one supplemental
compressor with at least one step is connected in series with
turbocharger.
18. Internal combustion engine based on one of the claims 1 to 16,
identified by the fact that there is at least one supplemental
compressor with at least one step is connected parallel with
turbocharger.
19. Internal combustion engine based on claim 2, identified by the
fact that the electric motor is powered by the 12-volt electrical
system.
20. Internal combustion engine based on one of the claims 1 to 19,
identified by the fact that the intake pipe assembly (18) includes
the supplemental compressor.
21. Internal combustion engine based on claim 20, identified by the
fact that the supplemental compressor is integrated in the intake
pipe.
22. Internal combustion engine based on claim 20, identified by the
fact that the supplemental compressor is built is onto the intake
pipe.
23. Internal combustion engine based on one of the claims 1 to 19,
identified by the fact that the cylinder head assembly (23)
includes the supplemental compressor.
24. Internal combustion engine based on claim 23, identified by the
fact that the supplemental compressor (4) is integrated in the
cylinder head or cylinder head cover.
25. Internal combustion engine based on claim 23, identified by the
fact that the supplemental compressor (4) is built onto the
cylinder head or cylinder head cover.
26. Internal combustion engine based on one of the claims 1 to 19,
identified by the fact that the air filter assembly (24) includes
the supplemental compressor (4).
27. Internal combustion engine based on claim 26, identified by the
fact that the supplemental compressor (4) is integrated in the air
filter casing.
28. Internal combustion engine based on claim 26, identified by the
fact that the supplemental compressor (4) is built onto the air
filter casing.
29. Internal combustion engine based on one of the claims 1 to 19,
identified by the fact that the exhaust assembly (25) includes the
supplemental compressor (4).
30. Internal combustion engine based on claim 29, identified by the
fact that the supplemental compressor is integrated in the exhaust
drive.
31. Internal combustion engine based on claim 29, identified by the
fact that the supplemental compressor (4) is built onto the exhaust
drive.
32. Internal combustion engine based on one of the claims 20 to 31,
identified by the fact that the spiral conduction is formed around
the compressor running wheel directly in the component
incorporating the compressor.
33. Internal combustion engine based on one of the claims 20 to 32,
identified by the fact that the drive (5) of the supplemental
compressor (4) is mounted vibration decoupling in the assembly
which incorporates the supplemental compressor (4).
34. Internal combustion engine based on one of the claims 1 to 33,
identified by the fact that the drive (5) of the supplemental
compressor (4) is attached to the coolant circuit of the internal
combustion engine in such a manner that the heat of the drive is
dissipated.
35. Internal combustion engine based on one of the claims 20 to 34,
identified by the fact that the assembly includes the closing or
switching means (20) in front of or behind the supplemental
compressor (4) includes.
36. Internal combustion engine based on one of the claims 20 to 35,
identified by the fact that the assembly (12) includes the
secondary air channels (12).
37. Internal combustion engine based on one of the claims 20 to 36,
identified by the fact that the assembly includes the exhaust
return (16).
38. Internal combustion engine based on one of the claims 20 to 37,
identified by the fact that the assembly includes the engine
ventilation.
39. Internal combustion engine based on one of the claims 20 to 38,
identified by the fact that the assembly includes the on board
diagnostic monitoring and/or the sensors.
40. Internal combustion engine based on one of the claims 20 to 39,
identified by the fact that the assembly includes the
turbocharger.
41. Internal combustion engine based on one of the claims 29 to 40,
identified by the fact that the components in or at the exhaust
area are thermally decoupled.
42. Internal combustion engine based on one of the claims 1 to 41,
identified by the fact that the internal combustion engine includes
a control of the supplemental compressor.
43. Internal combustion engine based on claim 42, identified by the
fact that the control of the supplemental compressor is integrated
into the internal combustion engine control.
44. Internal combustion engine based on claim 42, identified by the
fact that the control of the supplemental compressor is separate
from the internal combustion engine control.
45. Internal combustion engine based on claim 44, identified by the
fact that the parameters of the engine operational condition is an
input quantity of the control electronics.
46. Internal combustion engine based on claim 42, identified by the
fact that the control of the supplemental compressor is a partial
system in the central the internal combustion engine control.
47. Internal combustion engine based on claim 46, identified by the
fact that the partial systems are connected to each other with a
bus system.
48. Internal combustion engine based on claim 42, identified by the
fact that the control of the supplemental compressor a partial
system of the vehicle system.
49. Internal combustion engine based on claim 48, identified by the
fact that the partial systems are connected to each other with a
bus system.
Description
[0001] The invention refers to a charged internal combustion engine
based on the precharacterizing portion of claim 1.
[0002] Internal combustion engines with turbochargers, as commonly
known, use the energy contained in the exhaust and convert it into
mechanical energy in an exhaust turbine to power a turbo
compressor, which increases the pressure of the air supplied to the
internal combustion engine. To accomplish this, turbocharging can
occur in one or more steps.
[0003] In DE 198 37 978 A1, a two step turbocharging is disclosed,
where at least two turbines are attached in the exhaust section,
each of which power a turbo compressor. The exhaust turbines are
connected in series as high and low pressure level. First, the
exhaust flows through the high pressure turbine and then through
the low pressure turbine. The charge air is first compressed by the
low pressure compressor and then by the high pressure compressor
and, in certain cases after cooling by passing through a heat
exchanger, is supplied to the fresh gas side of the internal
combustion engine. As the RPM of the internal combustion engine is
increased, compression is increasingly shifted towards a single
stage which occurs exclusively in the low pressure compressor. In
comparison to one-step compression, charging is already possible at
low engine speeds with such a two-step charging process, but the
turbine operation, and therefore indirectly the compressor
operation, is limited by the energy contained in the exhaust. That
means that the unburned gas conducted into the internal combustion
engine can only be compressed a little, especially with lower
speeds. Without boost the internal combustion engine creates weak
torque, which leads to poor acceleration when used in a motor
vehicle.
[0004] The invention is concerned with the task of improving an
internal combustion engine of the type disclosed in the
precharacterizing portion of claim 1, so that it can generate high
torque even at low RPM, and thus making stationary torque available
more rapidly at partial load. In doing so, a high charge pressure
should build up early on, which can match the requirements of the
internal combustion engine.
[0005] Based on the invention, this task is solved by connecting a
supplemental compressor, which has a drive which is independent
from the working medium cycle of the internal combustion engine,
arranged in parallel or in series with the turbocharger.
[0006] In an especially beneficial embodiment, the supplemental
compressor is driven by an electric motor, and the supplemental
compressor is connected with the turbocharger in series. The
supplemental compressor is beneficially arranged upstream of the
turbocharger, in front of the turbocharger in the direction of
flow.
[0007] In a further developed embodiment, a closing or switching
means is located between the supplemental compressor and the
compressor of the turbocharger. Working with an electronic control
device for the electric motor and the closing or switching means
and power electronics required to support the electric motor, the
supplemental compressor supplements the turbocharger in operational
conditions in which the power taken from the exhaust flow is not
sufficient or not present.
[0008] In a beneficial execution, the supplemental compressor and
the compressor of the turbocharger are matched to each other in
such a manner, that a comparably wide characteristic diagram or
power curve results. The compression ratio of the supplemental
compressor and the compression ratio of the turbocharger compressor
are multiplied at each operating point.
[0009] In a further developed execution, the electric motor is
regulated based on the boost pressure output of the turbocharger in
relation to the prescribed boost pressure curve, so that the
supplemental compressor is switched off when the required boost
pressure is reached by the turbocharger. However, a predetermined
excess or reserve of the boost pressure may be maintained in
unsteady operating phases.
[0010] In a special execution, the supplemental compressor and the
turbocharger take in air via different intake sections, where the
closing-switching means guarantees that the air which is
pre-compressed by the supplemental compressor can only flow in the
direction of the turbocharger, or when the supplemental compressor
of the turbocharger is turned off, cannot conduct air through the
supplemental compressor any more. In an advantageous execution of
the invention, a charge cooler or heat exchanger is provided
between the turbocharger and the internal combustion engine. This
decreases the thermal stress of the components on the one hand, and
on the other decreases the specific volume of the compressed air
which had experienced heating during compression in the
supplemental compressor and turbocharger, thus resulting in an
increase in specific volume. By cooling and densifying the air, the
charged mass of the combustion engine is increased, which results
in a considerable increase in power.
[0011] Because the powering of the supplemental compressor can be
operated independently from the internal combustion engine, a
further advantage of the invention is that the supplemental
compressor also functions as a secondary air pump to conduct the
air in the catalytic converter to increase the conversation rate of
the catalytic converter in a cold condition.
[0012] Through an appropriate design of the turbine, a decrease in
the exhaust gas counterpressure is made possible. The execution of
the invention is obviously possible with various structural shapes
of turbochargers (turbochargers with waste gate or flap or also a
charger with variable turbine geometry). The use of multi-stage
turbochargers is as conceivable as the use of several supplemental
compressors, where the connection could occur not only in series
but also in parallel. Several heat exchangers could also be used
beneficially. If needed, the supplemental compressor and the
turbocharger can intake from the same intake section. A possible
bypass with a switch means makes it possible to detour the exhaust
gas side of the turbocharger. In order to reduce the amount of
nitrogen oxide emission through the exhausts coming from the
internal combustion engine, an exhaust gas recirculation system
(EGR) can be used, which draws in an amount of exhaust gas from a
engine exhaust conduit to a point upstream from the turbine of the
turbocharger, and conducts it into an engine intake conduit (DE 41
20 055 A1).
[0013] In an especially beneficial execution of the invention, the
supplemental compressor can be incorporated in an assembly of the
internal combustion engine. In doing so it is possible to either
incorporate only the supplemental compressor into the assembly or
also additional components or aggregates, such as the switching
and/or closing means in front of and behind the supplemental
compressor, if necessary, required throttle means or even the drive
for the supplemental compressor. When putting the supplemental
compressor in the intake pipe assembly, it is beneficial to
integrate the supplemental compressor in the intake pipe or to
build it onto the intake pipe. In a further developed execution,
the spiral guide around the compressor wheel can be directly formed
on the intake pipe. When mounting the supplemental compressor drive
at the intake pipe (or at the internal combustion engine or the
body), it is beneficial to provide a vibration decoupling fastener
in order to mitigate the vibration loads of the internal combustion
engine's stimulus.
[0014] In another beneficial execution of the invention, the
cylinder head assembly contains the supplemental compressor. For
this, the supplemental compressor can be integrated or mounted in
the cylinder head or in the cylinder head cover. Formation of the
spiral guide around the compressor wheel is possible directly on
the cylinder head. When mounting the supplemental compressor drive
at the cylinder head, vibration decoupling is beneficially
executed.
[0015] Other beneficial executions of the invention provide for
integration or building on the supplemental compressor in/at the
air filter casing or also in/at the exhaust train. Here also, in a
further developed execution, the spiral guide around the compressor
wheel is formed directly at the air filter casing or in the exhaust
train, and the supplemental compressor drive is mounted with
vibration decoupling. In a further developed execution of the
invention, when arranging the components in the exhaust, these are
thermally decoupled, i.e. connecting using a flange with minimal
heat conducting capabilities or shielding using a heat shield to
minimize the temperature stress on the components.
[0016] It is beneficial to connect the heat produced by the drive
using a coolant circuit corresponding with the supplemental
compressor drive to cool the supplemental compressor drive when
necessary.
[0017] In an especially beneficial execution of the invention, the
switching/closing/or throttle means located in front of or behind
the supplemental compressor could also be integrated or built into
the following components: intake pipe/cylinder head cover/air
filter casing/exhaust train. In a further developed execution--if
the supplemental compressor is used as a secondary air pump--the
secondary air conduit can also be integrated into or mounted into
the mentioned components. The same is possible for the exhaust gas
recirculation conduit and the engine ventilation. In the same way,
it is possible to integrate the on board diagnostic (OBD) monitor
and the sensors in the same assemblies. The turbocharger compressor
can also be integrated or build into the components in an
especially preferred execution.
[0018] A very compact and cost-effective construction is achieved
with the mentioned executions where the supplemental compressor is
integrated in the assemblies of the internal combustion engine, so
that, for example, when used in motor vehicles, the supplemental
compressor barely requires additional space compared to the
conventional internal combustion engines. Because especially short
pipes (air, gas and coolant pipes) are used with these integral
constructions, waste and leak risks are minimized.
[0019] In an especially beneficial execution, the invention
includes control of the supplemental compressor. In a first
execution, this control is integrated into the internal combustion
engine's control. In a further developed form of the invention, the
electronic control of the supplemental compressor is separate from
the internal combustion engine's control, where especially
advantageous parameters of the engine performance conditions
represent an input quantity of the control electronics.
[0020] In another beneficial execution of the invention, the
internal combustion engine's control is split into partial or
subcomponent systems, wherein the control of the supplemental
compressor is connected to the entire system as a partial system.
The individual partial systems communicate with each other using a
bus system (CAN-Bus). Benefits of this subdivision are the simple
monitoring and programming of the partial system.
[0021] In an especially beneficial execution of the invention, the
vehicle's entire system is split into partial systems (system
islands). The control of the supplemental compressor is
incorporated in such a partial system; the partial systems
communicate with each other using a bus system (CAN-Bus). An
advantage of this execution is the possibility to match the
individual systems with each other optimally, so that the primary
goal is optimally adjusting the fuel consumption for the power
output as currently or instantaneously necessary for the internal
combustion engine. Additional advantages are the simple monitoring
and programming of the partial systems and the possibility to add
additional components of control without great effort.
[0022] Preferred executions of the invention are explained in
references to the attached drawings. They show in:
[0023] FIG. 1 a schematic representation of an internal combustion
engine with one-step turbocharging and an supplemental compressor
powered by an electric motor in a first execution based on the
invention.
[0024] FIG. 2 a schematic of an internal combustion engine with
simple turbocharging and supplemental compressor with secondary air
channels, turbine bypass and exhaust return.
[0025] FIG. 3 a schematic of an internal combustion engine with
simple turbocharging and supplemental compressor with secondary air
channels, turbine bypass and exhaust return, with the supplemental
compressor integrated into the intake pipe assembly.
[0026] FIG. 4 a schematic of an internal combustion engine with
simple turbocharging and supplemental compressor with secondary air
channels, turbine bypass and exhaust return, with the supplemental
compressor integrated into the cylinder head assembly.
[0027] FIG. 5 a schematic of an internal combustion engine with
simple turbocharging and supplemental compressor with secondary air
channels, turbine bypass and exhaust return, with the supplemental
compressor integrated into the air filter casing assembly.
[0028] FIG. 6 a schematic of an internal combustion engine with
simple turbocharging and supplemental compressor with secondary air
channels, turbine bypass and exhaust return, with the supplemental
compressor integrated into the exhaust train assembly.
[0029] FIG. 7 a schematic of a control for the supplemental
compressor integrated into the engine control.
[0030] FIG. 8 a schematic of a control for the supplemental
compressor separate from the engine control.
[0031] FIG. 9 a schematic of an engine control split into partial
systems, including the control of the supplemental compressor as a
partial system.
[0032] FIG. 10 a schematic of a vehicle entire system split into
partial systems, including the control of the supplemental
compressor as a partial system.
[0033] FIG. 1 shows an internal combustion engine 1, which on the
fresh gas side 2 is connected to the compressor of a turbocharger 3
and a supplemental compressor 4. The supplemental compressor 4 is
connected to the turbocharger compressor 3 in series, and arranged,
in the flow direction, in front of the turbocharger compressor 3.
The supplemental compressor 4 is powered by an electric motor 5.
The turbine 7 of the turbocharger is connected to the internal
combustion engine 1 on the exhaust side 6. A closing or switching
means 8 is arranged between the supplemental compressor 4 and the
turbocharger compressor 3. Using the switch means 8, the
turbocharger compressor 3 can draw from its own intake area 9 as
well as from the supplemental compressor 4. The supplemental
compressor 4 draws from the intake area 10. If necessary, two air
mass measurers or meters as well as two filters are provided.
[0034] FIG. 2 shows an internal combustion engine with simple
turbocharging and an electrically powered supplemental compressor,
where the main design corresponds with FIG. 1. A closing means 11
is arranged in flow direction behind the supplemental compressor 4,
parallel to the closing or switching means 8, with which the mass
flow in the secondary air channels 12 can be controlled. A charge
cooler 13 is arranged in flow direction behind the turbocharger
compressor 3, which cools the fresh compressed gas before entry
into the internal combustion engine 1. Operation without
turbocharging is possible with a bypass 14, which diverts exhaust
gas to the exhaust side of the turbine 7 of the turbocharger. The
switching means 15 controls the mass flow, which is conducted on
the fresh gas side using the exhaust return 16.
[0035] FIG. 3 shows an internal combustion engine with all
components from FIG. 2. In this execution, the intake pipe assembly
18 includes the intake pipe 17, a throttle valve 19 and a
supplemental compressor 4, arranged sequentially going in the
upstream direction. In addition, drive 5 of the supplemental
compressor 4 and the switching or throttling means 20 are arranged
in front of and behind the supplemental compressor 4 in the intake
pipe assembly 18. Supplemental compressor 4 and turbocharger
compressor 3 draw raw air from the same intake area 9, in which the
air mass meter 21 and air filter 22 are connected.
[0036] FIG. 4 shows the schematic of an internal combustion engine
in which the cylinder head assembly 23 includes the supplemental
compressor 4, its drive 5 and the closing or switching means.
Integrating the supplemental compressor 4 and mounting the drive 5
in the or at the cylinder head cover 1.1 is beneficial.
[0037] FIG. 5 shows the schematic of an internal combustion engine,
in which the air filter casing assembly 24 incorporates the
supplemental compressor, its drive 5, the closing or switching
means 20 which are arranged in front of the supplemental compressor
4 in flow direction, the air mass measurer 21 and the air filter
22.
[0038] FIG. 6 shows the schematic of an internal combustion engine,
in which the exhaust train assembly 25 incorporates the
supplemental compressor 4, its drive 5, compressor 3 and turbine 7
of the turbocharger, the charge cooler 13 and the closing or
switching means 20.
[0039] FIG. 7 shows the schematic of an internal combustion engine,
in which the control 40 of the supplemental compressor is
integrated into the engine control 41.
[0040] FIG. 8 shows an internal combustion engine with a control 40
of the supplemental compressor which is separately executed from
the engine control 41, where the parameters of the engine
operational condition are input quality of the control electronics
of the supplemental compressor.
[0041] FIG. 9 shows the schematic of an engine control split into
partial systems, where, for example, the partial system of control
40 of the supplemental compressor, the control of the partial
system 42 of the intake pipe, of the partial system 43 of the
injection and the partial system 44 of the air filter are
represented. Additional partial systems are indicated. The partial
systems communicate with each other using the bus system 45
(CAN-bus).
[0042] FIG. 10 shows the schematic of a vehicle entire system split
into partial systems, where, for example the partial system 40 of
the control of the supplemental compressor, the partial system 46
(drive train), the partial system 47 (ABS), the partial system 48
(chassis), the partial system 49 (passenger compartment) and the
partial system 50 for heating are represented. The partial systems
communicate with each other using the bus system 45 (CAN-bus).
Reference Number List
[0043] 1 internal combustion engine
[0044] 2 fresh gas side
[0045] 3 turbocharger compressor
[0046] 4 supplemental compressor
[0047] 5 electric motor
[0048] 6 exhaust gas side
[0049] 7 turbine
[0050] 8 switch means
[0051] 9 intake area
[0052] 10 intake area
[0053] 11 closing means
[0054] 12 secondary air channels
[0055] 13 charge cooler
[0056] 14 bypass
[0057] 15 adjusting means
[0058] 16 exhaust return
[0059] 17 intake pipe
[0060] 18 intake pipe assembly
[0061] 19 throttle valve
[0062] 20 switching means
[0063] 21 air mass measurer
[0064] 22 air filter
[0065] 23 cylinder head assembly
[0066] 24 air filter casing assembly
[0067] 25 exhaust train assembly
[0068] 40 controller
[0069] 41 engine control
[0070] 42 partial system for the intake pipe
[0071] 43 partial system for the injection
[0072] 44 partial system for the air filter
[0073] 45 bus system
[0074] 46 partial system for the drive train
[0075] 47 ABS
[0076] 48 partial system for the chassis
[0077] 49 partial system for the passenger compartment
[0078] 50 partial system for the heating
* * * * *