U.S. patent application number 14/025851 was filed with the patent office on 2014-01-09 for heat pump circuit for vehicles.
This patent application is currently assigned to Bayerische Motoren Werke Aktiengesellschaft. The applicant listed for this patent is Bayerische Motoren Werke Aktiengesellschaft. Invention is credited to Robert HERBOLZHEIMER, Florian SCHNEIDER.
Application Number | 20140007605 14/025851 |
Document ID | / |
Family ID | 45976337 |
Filed Date | 2014-01-09 |
United States Patent
Application |
20140007605 |
Kind Code |
A1 |
SCHNEIDER; Florian ; et
al. |
January 9, 2014 |
Heat Pump Circuit for Vehicles
Abstract
A heat pump circuit for heating a vehicle passenger compartment
and/or a vehicle component is provided. The heat pump circuit
includes an electrical heating device arranged to heat a
refrigerant flowing through the heat pump circuit.
Inventors: |
SCHNEIDER; Florian;
(Eichenau, DE) ; HERBOLZHEIMER; Robert;
(Groebenzell, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Bayerische Motoren Werke Aktiengesellschaft |
Muenchen |
|
DE |
|
|
Assignee: |
Bayerische Motoren Werke
Aktiengesellschaft
Muenchen
DE
|
Family ID: |
45976337 |
Appl. No.: |
14/025851 |
Filed: |
September 13, 2013 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2012/056172 |
Apr 4, 2012 |
|
|
|
14025851 |
|
|
|
|
Current U.S.
Class: |
62/238.7 |
Current CPC
Class: |
F25B 30/02 20130101;
B60H 2001/00949 20130101; B60H 1/00385 20130101; B60H 1/00921
20130101; F25B 2400/01 20130101 |
Class at
Publication: |
62/238.7 |
International
Class: |
F25B 30/02 20060101
F25B030/02 |
Foreign Application Data
Date |
Code |
Application Number |
May 26, 2011 |
DE |
10 2011 076 507.7 |
Claims
1. A heat pump circuit for a vehicle, comprising: a vehicle; a
circuit in the vehicle through which a heat pump is arranged to
circulate a refrigerant medium provided for transferring heat to at
least one of a passenger cabin of the vehicle and a vehicle
component; and an electric heater device arranged to heat the
refrigerant medium flowing through the heat pump circuit.
2. The heat pump circuit according to claim 1, wherein the heat
pump circuit includes a first refrigerant medium branch and a
second refrigerant medium branch parallel to the first refrigerant
medium branch.
3. The heat pump circuit according to claim 2, wherein the heat
pump is a refrigerant medium compressor, the heat pump circuit
includes a first heat exchanger, the refrigerant medium compressor
includes a pressure output connected to an input of the first heat
exchanger, and the first heat exchanger is configured to directly
or indirectly release heat from the refrigerant medium to the at
least one of the passenger cabin and the vehicle component.
4. The heat pump circuit according to claim 3, wherein a branching
point is provided in the heat pump circuit downstream in a
direction of flow of the refrigerant medium from the first heat
exchanger and upstream of the first and second refrigerant medium
branches.
5. The heat pump circuit according to claim 4, wherein the heat
pump circuit includes a second heat exchanger arranged in the first
refrigerant medium branch, the second heat exchanger being
configured to permit flow of air through the second heat
exchanger.
6. The heat pump circuit according to claim 5, wherein the electric
heater device is arranged in the second refrigerant medium
branch.
7. The heat pump circuit according to claim 6, wherein the second
refrigerant medium branch has a refrigerant medium tube through
which refrigerant medium flows, the refrigerant medium tube being
arranged to be heated by the electric heater device.
8. The heat pump circuit according to claim 7, wherein at least one
expansion element is arranged downstream in the direction of flow
of the refrigerant medium from the first heat exchanger and
upstream of the second heat exchanger and the electric heater
device.
9. The heat pump circuit according to claim 8, wherein a first
expansion element of the at least one expansion element is arranged
in the first refrigerant medium branch upstream of the second heat
exchanger.
10. The heat pump circuit according to claim 9, wherein a second
expansion element of the at least one expansion element is arranged
in the second refrigerant medium branch upstream of the electric
heater device.
11. The heat pump circuit according to claim 10, wherein at least
one shut-off device is included in at least one of the first
refrigerant medium branch and the second refrigerant medium branch,
the at least one shut-off device being configured to permit
selective shut-off of refrigerant medium flow.
12. A heat pump circuit according to claim 11, wherein air does not
directly flow around or through components of the second
refrigerant medium branch.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of PCT International
Application No. PCT/EP2012/056172, filed Apr. 4, 2012, which claims
priority under 35 U.S.C. .sctn.119 from German Patent Application
No. DE 10 2011 076 507.7, filed May 26, 2011, the entire
disclosures of which are expressly incorporated by reference
herein.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] The present invention relates to a heat pump circuit for
heating a passenger cabin of a vehicle, the heat pump circuit
including an electric heater.
[0003] A laundry drying machine having a heat pump circuit is known
from European patent document no. EP 1 983 095 A2, in which a
heater is arranged therein. The heat pump circuit has--when viewed
in the direction of flow of the refrigerant medium flowing through
the heat pump circuit--a compressor, a condenser, an auxiliary heat
exchanger, an evaporator, and a heater. The heater is arranged
between an output of the evaporator and a suction intake of the
compressor, in series in the heat pump circuit. The heater is
included for the purpose of raising the temperature in the heat
pump circuit at the start of the drying process, and/or for the
purpose of maintaining the refrigerant medium in the gaseous phase
during operating modes in which there is a risk of the compressor
taking in liquid refrigerant medium.
[0004] The problem addressed by the invention is that of creating a
heat pump circuit which is also suitable for other technology
fields.
[0005] The invention proceeds from the concept of heating a
vehicle--meaning the passenger cabin of a vehicle, and/or
components of a vehicle which must be kept at temperature, such as
a high-voltage storage device or the like, for example--by a heat
pump arrangement. It is known that the degree of efficiency of a
heat pump arrangement depends on the temperature of the surrounding
air used as the heat source. At low temperatures, such as in winter
for example, the degree of efficiency and/or the coefficient of
performance of a conventional heat pump system is so minimal that
it is relatively uneconomical to use a heat pump system.
[0006] A central concept of the invention is the idea of equipping
a vehicle with a heat pump circuit which, in contrast to
conventional heat pump circuits, has an additional electrical
heater device, by which it is possible to supply heat to the
refrigerant medium flowing through the heat pump circuit. By
"preheating" the refrigerant medium, it is thereby possible to
reach a sufficiently high degree of efficiency and/or a
sufficiently high coefficient of performance, even at low
surrounding air temperatures, to make reasonable the use of the
invention in vehicles.
[0007] According to one implementation of the invention, the heat
pump circuit has two refrigerant medium branches through which
refrigerant medium flows, particularly a first refrigerant medium
branch and a second refrigerant medium branch which is arranged
parallel thereto and/or "connected" in parallel thereto.
[0008] A heat pump circuit according to the invention has a
refrigerant medium compressor with a pressure outlet having a flow
connection to an input of a first heat exchanger. The first heat
exchanger is included for the purpose of releasing heat from the
refrigerant medium to the passenger cabin and/or to the vehicle
components being heated (such as a high-voltage storage device, for
example).
[0009] Viewed in the direction in which the refrigerant medium
flows, a "branching point" is included in the fluid system of the
heat pump circuit after the first heat exchanger. At this point,
the heat pump circuit branches into the two refrigerant medium
branches mentioned above.
[0010] A second heat exchanger can be configured in a first branch
of the two refrigerant medium branches. During heat pump operation,
the second heat exchanger functions as an evaporator. Heat
contained in the surrounding air and/or in the airstream is
released via the second heat exchanger to the cooler refrigerant
medium flowing through the second heat exchanger.
[0011] According to one implementation of the invention, the
electrical heater device is arranged in the second refrigerant
medium branch, the same arranged parallel to the first refrigerant
medium branch, which is a very key difference with respect to the
document EP 1 983 095 A2 mentioned above. By way of example, the
second refrigerant medium branch can have a refrigerant medium tube
through which refrigerant medium flows, or a component embodied in
another manner, through which refrigerant medium flows, wherein
said tube or component can be heated by the electrical heater
device.
[0012] A shut-off device can be functionally assigned to each of
the two refrigerant medium branches, wherein the refrigerant medium
branch can be shut off via the respective shut-off device. At very
low outside temperatures, when it is not possible to produce a
significant heat input via the second heat exchanger, the first
refrigerant medium branch can be shut off via the assigned shut-off
device, such that all of the circulating refrigerant medium flows
through the second refrigerant medium branch.
[0013] As an alternative, refrigerant medium can also flow through
both of the refrigerant medium branches in parallel.
[0014] In a further operating mode, the second refrigerant medium
branch can be shut off via the assigned shut-off device, wherein
the total heat input occurs via the second heat exchanger--meaning
via the heat contained in the surrounding air.
[0015] At least one expansion element is arranged between an output
of the first heat exchanger, on the one hand, and the second heat
exchanger and the heater device on the other hand. An expansion
element is preferably arranged in each of the two refrigerant
medium branches. A first expansion element can be arranged in the
first refrigerant medium branch before the second heat exchanger,
and a second expansion element can be arranged in the second
refrigerant medium branch before the heater device.
[0016] As an alternative thereto, the configuration can have only
one single expansion element which is arranged before the
"branching point" at which the heat pump circuit branches into the
two refrigerant medium branches.
[0017] As already mentioned, the second heat exchanger is arranged
in the vehicle in such a manner that air and/or the airstream flows
around and/or through it. By way of example, an electric fan can be
included which actively blows air through the second heat
exchanger. In contrast thereto, the second refrigerant medium
branch and/or the components thereof can be arranged in a protected
position in the vehicle, particularly in the engine compartment of
the vehicle, rather than having the airstream flow around or
through it and/or them--or at least not directly.
[0018] By a heat pump circuit according to the invention, in
comparison to the conventional heat pump circuits (with no heater
device), with circuit components which are otherwise sized the
same, it is possible to achieve a significant increase in
performance. This enables an economical deployment in vehicles, and
particularly even in the cold seasons--meaning at low surrounding
air temperatures. The arrangement of the electrical heater device
in a bypass to the second heat exchanger can be very simply
implemented in terms of construction--for example as an
electrically heated refrigerant medium tube.
[0019] The invention is also particularly suited for hybrid- or
purely electric vehicles. In these applications, the heat pump
arrangement can be used for heating high-voltage components, such
as a high-voltage storage device or power electronics, for example.
As such, high-voltage components which must be heated can be
arranged at any point in the vehicle, and need not necessarily be
arranged in the vehicle interior.
[0020] Other objects, advantages and novel features of the present
invention will become apparent from the following detailed
description of one or more preferred embodiments when considered in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0021] FIG. 1 is a schematic illustration of an embodiment of the
present invention.
DETAILED DESCRIPTION OF THE DRAWING
[0022] FIG. 1 shows a heat pump circuit 1 having a refrigerant
medium compressor 2 which is connected to an input 4 of a first
heat exchanger 5 via a liquid line 3. Refrigerant medium which is
compressed by the refrigerant medium compressor 2 and accordingly
heated flows through the first heat exchanger 5 and thereby
releases heat to a passenger cabin of a vehicle which is not
illustrated here in greater detail, or to a vehicle component (not
illustrated), of the vehicle, being heated. This is symbolized by
an arrow 6.
[0023] One output 7 of the first heat exchanger 5 is connected to a
branching point 9 via a refrigerant medium conduit 8, wherein the
heat pump circuit 1 branches at said branching point 9 into a first
refrigerant medium branch 10 and a second refrigerant medium branch
11. The first refrigerant medium branch 10 has a first expansion
element 12 in which the refrigerant medium arriving from the first
heat exchanger 5 releases pressure and is cooled.
[0024] The cooled refrigerant medium coming from the first
expansion element 12 flows through a second heat exchanger 13,
which absorbs heat from the surrounding air. This is symbolized by
arrow 14. The second heat exchanger 13 can be arranged in the
vehicle in such a manner that the airstream flows directly around
or through it. An output 15 of the second heat exchanger 13 has a
flow connection to a suction connector of the refrigerant medium
compressor 2, via a liquid line 16 and a collector 17.
[0025] The second refrigerant medium branch 11 is arranged parallel
to the first refrigerant medium branch 10 and has--when viewed in
the direction of flow of the refrigerant medium--a second expansion
element 19, and a component 21 through which refrigerant medium
flows, said component being able to be heated by an electric heater
device 20. The component 21 can be a simple refrigerant medium tube
through which refrigerant medium flows, or also a heat exchanger,
by way of example.
[0026] As an alternative to the embodiment shown in FIG. 1, the
configuration can also have only one single expansion element. This
can be arranged upstream of the branching point 9, when viewed in
the direction of refrigerant medium flow.
[0027] In addition, a shut-off device can be included in each of
the two refrigerant medium branches 10, 11--for example in the
region between the branching point 9 and the first and/or second
expansion element 12, 19. As an alternative, the expansion elements
12, 19 can also be designed as expansion elements which can be shut
off In this manner, three different operating states can be "run"
in principle--namely: [0028] a first operating state in which
refrigerant medium flows through the two refrigerant medium
branches 10, 11 in parallel, [0029] a second operating state in
which the second refrigerant medium branch 11 is shut off and the
entire volume of refrigerant medium flows through the first
refrigerant medium branch 10, which may be practical when the
surrounding air temperature is high, for example (seasonal
transition and/or summer operation), [0030] a third operating state
in which the first refrigerant medium branch 10 is shut off and the
entire volume of refrigerant medium flows through the second
refrigerant medium branch 11, which may be practical at low
surrounding air temperatures (winter operation), for example. In
this case, the refrigerant medium can be (pre-)heated via the
electric heater device 20.
[0031] The foregoing disclosure has been set forth merely to
illustrate the invention and is not intended to be limiting. Since
modifications of the disclosed embodiments incorporating the spirit
and substance of the invention may occur to persons skilled in the
art, the invention should be construed to include everything within
the scope of the appended claims and equivalents thereof.
* * * * *