U.S. patent application number 15/141874 was filed with the patent office on 2017-11-02 for caloric water heater appliance.
The applicant listed for this patent is General Electric Company. Invention is credited to David G. Beers, Michael Alexander Benedict.
Application Number | 20170314814 15/141874 |
Document ID | / |
Family ID | 60157406 |
Filed Date | 2017-11-02 |
United States Patent
Application |
20170314814 |
Kind Code |
A1 |
Benedict; Michael Alexander ;
et al. |
November 2, 2017 |
Caloric Water Heater Appliance
Abstract
A water heater appliance includes a first heat exchanger that is
coupled to a tank. The water heater appliance also includes a
caloric heat pump system that is configured for heating liquid
within the tank via the first heat exchanger. The caloric heat pump
system includes a plurality of caloric material stages. A field
generator is positioned such that the caloric material stages are
moved in and out of a field of the field generator during operation
of the caloric heat pump system.
Inventors: |
Benedict; Michael Alexander;
(Louisville, KY) ; Beers; David G.; (Elizabeth,
IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company |
Schenectady |
NY |
US |
|
|
Family ID: |
60157406 |
Appl. No.: |
15/141874 |
Filed: |
April 29, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F24H 4/04 20130101; F24H
7/04 20130101; F24H 7/002 20130101 |
International
Class: |
F24H 4/04 20060101
F24H004/04; F24H 7/04 20060101 F24H007/04; F24H 7/00 20060101
F24H007/00 |
Claims
1. A water heater appliance, comprising: a tank; a first heat
exchanger coupled to the tank for delivery of heat to liquid within
the tank; a second heat exchanger; and a caloric heat pump system
configured for heating liquid within the tank at the first heat
exchanger, the caloric heat pump system comprising a plurality of
caloric material stages; a field generator positioned proximate the
caloric material stages, the field generator positioned such that
the caloric material stages are sequentially moved in and out of a
field of the field generator during operation of the caloric heat
pump system; and a pump for circulating a heat transfer fluid
between the first and second heat exchangers and the caloric
material stages.
2. The water heater appliance of claim 1, wherein the tank extends
between a top portion and a bottom portion along a vertical
direction, an inlet of the first heat exchanger positioned at the
bottom portion of the tank, an outlet of the first heat exchanger
positioned at the top portion of the tank.
3. The water heater appliance of claim 2, wherein the first heat
exchanger comprises a conduit wound around the tank at an outer
surface of the tank.
4. The water heater appliance of claim 3, wherein the conduit of
the first heat exchanger is wound around the tank between the inlet
and the outlet of the first heat exchanger.
5. The water heater appliance of claim 3, wherein adjacent windings
of the conduit are spaced apart from one another along the vertical
direction on the outer surface of the tank.
6. The water heater appliance of claim 5, wherein the adjacent
windings of the conduit are uniformly spaced apart from one another
along the vertical direction on the outer surface of the tank.
7. The water heater appliance of claim 3, wherein the conduit is
wound onto the outer surface of the tank at a constant rate.
8. The water heater appliance of claim 1, wherein the heat transfer
fluid comprises water.
9. The water heater appliance of claim 1, further comprising an
electric heating element disposed within the tank and operable to
heat liquid within the tank.
10. The water heater appliance of claim 1, further comprising a
casing, the tank, the second heat exchanger and the caloric
material stages all disposed within the casing, the second heat
exchanger and the caloric material stages positioned over the tank
within the casing.
11. A water heater appliance, comprising: a casing; a tank disposed
within the casing; a first heat exchanger disposed within the
casing and coupled to the tank for delivery of heat to liquid
within the tank; a second heat exchanger disposed within the casing
such that the second heat exchanger is spaced apart from the first
heat exchanger; a caloric heat pump system disposed within the
casing and configured for heating liquid within the tank via the
first heat exchanger, the caloric heat pump system comprising a
plurality of caloric material stages; a field generator positioned
proximate the caloric material stages, the field generator
positioned such that the caloric material stages are moved in and
out of a field of the field generator during operation of the
caloric heat pump system; and a pump for circulating an aqueous
heat transfer fluid between the first and second heat exchangers
and the caloric material stages.
12. The water heater appliance of claim 11, wherein the tank
extends between a top portion and a bottom portion along a vertical
direction, an inlet of the first heat exchanger positioned at the
bottom portion of the tank, an outlet of the first heat exchanger
positioned at the top portion of the tank.
13. The water heater appliance of claim 12, wherein the first heat
exchanger comprises a conduit wound around the tank at an outer
surface of the tank.
14. The water heater appliance of claim 13, wherein the conduit of
the first heat exchanger is wound around the tank between the inlet
and the outlet of the first heat exchanger.
15. The water heater appliance of claim 13, wherein adjacent
windings of the conduit are spaced apart from one another along the
vertical direction on the outer surface of the tank.
16. The water heater appliance of claim 15, wherein the adjacent
windings of the conduit are uniformly spaced apart from one another
along the vertical direction on the outer surface of the tank.
17. The water heater appliance of claim 13, wherein the conduit is
wound onto the outer surface of the tank at a constant rate.
18. The water heater appliance of claim 11, further comprising an
electric heating element disposed within the tank and operable to
heat liquid within the tank.
19. The water heater appliance of claim 11, wherein the caloric
material stages and the second heat exchanger are positioned over
the tank within the casing.
Description
FIELD OF THE INVENTION
[0001] The present subject matter relates generally to water heater
appliances, such as heat pump water heater appliances
BACKGROUND OF THE INVENTION
[0002] Heat pump water heaters are gaining broader acceptance as a
more economic and ecologically-friendly alternative to electric
water heaters. Heat pump water heaters include a sealed system for
heating water to the set temperature. Conventional sealed system
technology typically utilizes a heat pump that relies on
compression and expansion of a fluid refrigerant to receive and
reject heat in a cyclic manner so as to effect a desired
temperature change or i.e. transfer heat energy from one location
to another. This cycle can be used to provide e.g., for the
receiving of heat from the environment and the rejecting of such
heat to a tank of water. A variety of different fluid refrigerants
have been developed that can be used with the heat pump in such
systems.
[0003] While improvements have been made to such heat pump systems
that rely on the compression of fluid refrigerant, at best such can
still only operate at about forty-five percent or less of the
maximum theoretical Carnot cycle efficiency. Also, some fluid
refrigerants have been discontinued due to environmental concerns.
The range of ambient temperatures over which certain
refrigerant-based systems can operate may be impractical for
certain locations. Other challenges with heat pumps that use a
fluid refrigerant exist as well.
[0004] Accordingly, a water heater appliance with features for
efficiently heating water within the water heater appliance would
be useful. In particular, a water heater appliance with features
for efficiently heating water without requiring compression of
fluid refrigerant would be useful.
BRIEF DESCRIPTION OF THE INVENTION
[0005] The present subject matter provides a water heater
appliance. A first heat exchanger is coupled to a tank, and a
caloric heat pump system is configured for heating liquid within
the tank via the first heat exchanger. The caloric heat pump system
includes a plurality of caloric material stages. A field generator
is positioned such that the caloric material stages are moved in
and out of a field of the field generator during operation of the
caloric heat pump system. Additional aspects and advantages of the
invention will be set forth in part in the following description,
or may be apparent from the description, or may be learned through
practice of the invention.
[0006] In a first exemplary embodiment, a water heater appliance is
provided. The water heater appliance includes a tank. A first heat
exchanger is coupled to the tank for delivery of heat to liquid
within the tank. The water heater appliance also includes a second
heat exchanger. A caloric heat pump system is configured for
heating liquid within the tank via the first heat exchanger. The
caloric heat pump system includes a plurality of caloric material
stages. A field generator is positioned proximate the caloric
material stages. The field generator is positioned such that the
caloric material stages are sequentially moved in and out of a
field of the field generator during operation of the caloric heat
pump system. The caloric heat pump system further includes a pump
for circulating a heat transfer fluid between the first and second
heat exchangers and the caloric material stages.
[0007] In a second exemplary embodiment, a water heater appliance
is provided. The water heater appliance includes a casing. A tank
is disposed within the casing. A first heat exchanger is disposed
within the casing and is coupled to the tank for delivery of heat
to liquid within the tank. A second heat exchanger is also disposed
within the casing such that the second heat exchanger is spaced
apart from the first heat exchanger. A caloric heat pump system is
disposed within the casing and is configured for heating liquid
within the tank via the first heat exchanger. The caloric heat pump
system includes a plurality of caloric material stages. A field
generator is positioned proximate the caloric material stages. The
field generator is positioned such that the caloric material stages
are moved in and out of a field of the field generator during
operation of the caloric heat pump system. The caloric heat pump
system also includes a pump for circulating an aqueous heat
transfer fluid between the first and second heat exchangers and the
caloric material stages.
[0008] These and other features, aspects and advantages of the
present invention will become better understood with reference to
the following description and appended claims. The accompanying
drawings, which are incorporated in and constitute a part of this
specification, illustrate embodiments of the invention and,
together with the description, serve to explain the principles of
the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A full and enabling disclosure of the present invention,
including the best mode thereof, directed to one of ordinary skill
in the art, is set forth in the specification, which makes
reference to the appended figures.
[0010] FIG. 1 provides a perspective view of a water heater
appliance according to an exemplary embodiment of the present
subject matter.
[0011] FIG. 2 provides a schematic view of certain components of
the exemplary water heater appliance of FIG. 1.
[0012] FIG. 3 provides a perspective view of a heat pump according
to an exemplary embodiment of the present subject matter.
[0013] FIG. 4 provides an exploded view of the exemplary heat pump
of FIG. 3.
[0014] FIG. 5 provides a section view of the exemplary heat pump of
FIG. 3.
[0015] FIG. 6 provides perspective view of the exemplary heat pump
of FIG. 3.
[0016] FIG. 7 provides a schematic representation of various steps
in the use of a stage of the exemplary heat pump of FIG. 3.
DETAILED DESCRIPTION
[0017] Reference now will be made in detail to embodiments of the
invention, one or more examples of which are illustrated in the
drawings. Each example is provided by way of explanation of the
invention, not limitation of the invention. In fact, it will be
apparent to those skilled in the art that various modifications and
variations can be made in the present invention without departing
from the scope or spirit of the invention. For instance, features
illustrated or described as part of one embodiment can be used with
another embodiment to yield a still further embodiment. Thus, it is
intended that the present invention covers such modifications and
variations as come within the scope of the appended claims and
their equivalents.
[0018] The present subject matter is directed to a water heater
appliance with a caloric heat pump system for heating water within
the water heater appliance. While described in greater detail below
in the context of a magneto-caloric heat pump system, one of skill
in the art will recognize that other suitable caloric materials may
be used in a similar manner to heat water within the water heater
appliance, i.e., apply a field, move heat, remove the field, move
heat. For example, electro-caloric material heats up and cools down
within increasing and decreasing electric fields. As another
example, elasto-caloric material heats up and cools down when
exposed to increasing and decreasing mechanical strain. As yet
another example, baro-caloric material heats up and cools down when
exposed to increasing and decreasing pressure. Such materials
another other similar caloric materials may be used in place of or
in addition to the magneto-caloric material described below to heat
water within the water heater appliance. Thus, caloric material is
used broadly herein to encompass materials that undergo heating or
cooling when exposed to a changing field from a field generator,
where the field generator may be an electric field generator, an
actuator for applying mechanical stress or pressure, etc.
[0019] FIG. 1 provides a perspective view of a water heater
appliance 100 according to an exemplary embodiment of the present
subject matter. It should be understood that water heater appliance
100 is provided by way of example only and that the present subject
matter may be used in or with any suitable water heater appliance.
Thus, other configurations for water heater appliance different
from that shown in FIGS. 1 and 2 may be used with the present
subject matter as well.
[0020] Water heater appliance 100 includes a casing 102. A tank 112
(FIG. 2) is mounted within casing 102. Tank 112 defines an interior
volume 114 for heating water therein. Water heater appliance 100
also includes a cold water conduit 104 and a hot water conduit 106
that are both in fluid communication with tank 112 within casing
102. As an example, cold water from a water source, e.g., a
municipal water supply or a well, enters water heater appliance 100
through cold water conduit 104. From cold water conduit 104, such
cold water enters interior volume 114 of tank 112 wherein the water
is heated to generate heated water. Such heated water exits water
heater appliance 100 at hot water conduit 106 and, e.g., is
supplied to a bath, shower, sink or any other suitable feature.
[0021] As may be seen in FIG. 1, water heater appliance 100 extends
between a top portion 108 and a bottom portion 109 along a vertical
direction V. Thus, water heater appliance 100 is generally
vertically oriented. Water heater appliance 100 can be leveled,
e.g., such that casing 102 is plumb in the vertical direction V, in
order to facilitate proper operation of water heater appliance 100.
A drain pan 110 is positioned at bottom portion 109 of water heater
appliance 100 such that water heater appliance 100 sits on drain
pan 110. Drain pan 110 sits beneath water heater appliance 100
along the vertical direction V, e.g., to collect water that leaks
from water heater appliance 100 or water that condenses on a second
heat exchanger 128 of water heater appliance 100.
[0022] FIG. 2 provides a schematic view of certain components of
water heater appliance 100 including an interior volume 114 of a
tank 112 and a machinery compartment 140. Machinery compartment 140
may be positioned above tank 112 within casing 102 (FIG. 1). As
shown in FIG. 2, water heater appliance 100 includes an upper
heating element 118, a lower heating element 119 and a heat pump
system 120 for heating water within interior volume 114 of tank
112. Upper and lower heating elements 118 and 119 can be any
suitable heating elements. For example, upper heating element 118
and/or lower heating element 119 may be an electric resistance
element, a microwave element, an induction element, or any other
suitable heating element or combination thereof. Lower heating
element 119 may also be a gas burner. Upper and lower heating
elements 118 and 119 may be mounted to and positioned within tank
112, as shown in FIG. 2.
[0023] Heat pump system 120 includes a pump 122, a first heat
exchanger 124, a heat pump 126 and a second heat exchanger 128.
Various components of heat pump system 120 may be positioned within
casing 102, including pump 122, first heat exchanger 124, heat pump
126 and second heat exchanger 128. In particular, pump 122, heat
pump 126 and second heat exchanger 128 may be positioned within
machinery compartment 140 above tank 112, while first heat
exchanger 124 is positioned on or at tank 112 below machinery
compartment 140.
[0024] First heat exchanger 124 is assembled in a heat exchange
relationship with tank 112 in order to heat water within interior
volume 114 of tank 112 during operation of heat pump system 120.
Thus, first heat exchanger 124 may be positioned at or adjacent
interior volume 114 of tank 112 for the addition of heat thereto. A
heat transfer fluid such as e.g., an aqueous solution, flowing
within first heat exchanger 124 rejects heat to tank 112 and/or
interior volume 114 of tank 112 thereby heating its contents. As an
example, first heat exchanger 124 may be a conduit, such as copper
or aluminum tubing, wound around tank 112 at an outer surface 180
of tank 112. When first heat exchanger 124 is a conduit wound
around tank 112, first heat exchanger 124 may be brazed, soldered
or otherwise suitably mounted to tank 112 at outer surface 180 of
tank 112.
[0025] First heat exchanger 124 extends between an inlet 170 and an
outlet 172. The heat transfer fluid from heat pump 126 may enter
first heat exchanger 124 at inlet 170 of first heat exchanger 124,
and the heat transfer fluid may exit first heat exchanger 124 at
outlet 172 of first heat exchanger 124. Inlet 170 of first heat
exchanger 124 may be positioned at or proximate bottom portion 109
of tank 112. Conversely, outlet 172 of first heat exchanger 124 may
be positioned at or proximate top portion 108 of tank 112. Thus,
inlet 170 of first heat exchanger 124 may be positioned below
outlet 172 of first heat exchanger 124 along the vertical direction
V on tank 112. In such a manner, the heat transfer fluid within
first heat exchanger 124 may first heat relatively cool water at
bottom portion 109 of tank 112 before flowing upwardly along the
vertical direction V to heat relatively hot water at top portion
108 of tank 112. In such a manner, efficient heat transfer between
the heat transfer fluid within first heat exchanger 124 and water
within interior volume 114 of tank 112 may be facilitated.
[0026] First heat exchanger 124 may be wound around tank 112
between inlet and outlet 170, 172 of first heat exchanger 124. As
an example, first heat exchanger 124 may be wound around tank 112
such that adjacent windings of first heat exchanger 124 are spaced
apart from one another along the vertical direction V on outer
surface 180 of tank 112, as shown in FIG. 2. In particular,
adjacent windings of first heat exchanger 124 may be uniformly
spaced apart from one another along the vertical direction V by a
pitch P on outer surface 180 of tank 112. Thus, first heat
exchanger 124 may be wound onto outer surface 180 of tank 112 at a
constant rate. First heat exchanger 124 may be wound onto outer
surface 180 of tank 112 at any suitable constant rate, such as
e.g., about six windings per foot of tank 112 along the vertical
direction V. By uniformly spacing adjacent windings of first heat
exchanger 124 on outer surface 180 of tank 112, uniform heat
transfer between the heat transfer fluid within first heat
exchanger 124 and water within interior volume 114 of tank 112
along the vertical direction V may be facilitated.
[0027] After heating water within tank 112, the heat transfer fluid
flows out of first heat exchanger 124 by line 160 to heat pump 126.
As will be further described herein, the heat transfer fluid
rejects additional heat to magneto-caloric material (MCM) in heat
pump 126 and then flows by line 162 to second heat exchanger 128,
e.g., that is disposed within machinery compartment 140. The heat
transfer fluid within second heat exchanger 128 is heated by the
environment, machinery compartment 140, and/or another location
external to interior volume 114 of tank 112 via second heat
exchanger 128. A fan 132 may be used to create a flow of air across
second heat exchanger 128 and thereby improve the rate of heat
transfer from the environment.
[0028] From second heat exchanger 128, the heat transfer fluid
returns by line 164 to pump 122 and then to heat pump 126 where, as
will be further described below, the heat transfer fluid receives
heat from the MCM in heat pump 126. The now hotter heat transfer
fluid flows by line 166 to first heat exchanger 124 to reject heat
to tank 112 and/or interior volume 114 of tank 112 and repeat the
cycle as just described. Pump 122 connected into line 164 causes
the heat transfer fluid to circulate in heat pump system 120. Motor
130 is in mechanical communication with heat pump 126 as will
further described. During operation of heat pump system 120, the
heat transfer fluid may not undergo a phase change.
[0029] Heat pump system 120 is provided by way of example only.
Other configurations of heat pump system 120 may be used as well.
For example, lines 160, 162, 164 and 166 provide fluid
communication between the various components of heat pump system
120 but other heat transfer fluid recirculation loops with
different lines and connections may also be employed. For example,
pump 122 can also be positioned at other locations or on other
lines in heat pump system 120. Still other configurations of heat
pump system 120 may be used as well. Heat pump 126 may be any
suitable heat pump with MCM. For example, heat pump 126 may be
constructed or arranged in the manner described in U.S. Patent
Publication No. 2014/0165594 of Michael Alexander Benedict, which
is hereby incorporated by reference in its entirety.
[0030] Water heater appliance 100 also includes a temperature
sensor 116. Temperature sensor 116 is configured for measuring a
temperature of water within interior volume 114 of tank 112.
Temperature sensor 116 can be positioned at any suitable location
within water heater appliance 100. For example, temperature sensor
116 may be positioned within interior volume 114 of tank 112 or may
be mounted to tank 112 outside of interior volume 114 of tank 112.
When mounted to tank 112 outside of interior volume 114 of tank
112, temperature sensor 116 can be configured for indirectly
measuring the temperature of water within interior volume 114 of
tank 112. For example, temperature sensor 116 can measure the
temperature of tank 112 and correlate the temperature of tank 112
to the temperature of water within interior volume 114 of tank 112.
Temperature sensor 116 can be any suitable temperature sensor. For
example, temperature sensor 116 may be a thermocouple or a
thermistor.
[0031] Water heater appliance 100 further includes a controller 150
that is configured for regulating operation of water heater
appliance 100. Controller 150 is in, e.g., operative, communication
with upper and lower heating elements 118 and 119, pump 122, motor
130, fan 132 and temperature sensor 116. Thus, controller 150 can
selectively activate upper and lower heating elements 118 and 119
and/or pump 122 and motor 130 in order to heat water within
interior volume 114 of tank 112.
[0032] Controller 150 includes memory and one or more processing
devices such as microprocessors, CPUs or the like, such as general
or special purpose microprocessors operable to execute programming
instructions or micro-control code associated with operation of
water heater appliance 100. The memory can represent random access
memory such as DRAM, or read only memory such as ROM or FLASH. The
processor executes programming instructions stored in the memory.
The memory can be a separate component from the processor or can be
included onboard within the processor. Alternatively, controller
150 may be constructed without using a microprocessor, e.g., using
a combination of discrete analog and/or digital logic circuitry
(such as switches, amplifiers, integrators, comparators,
flip-flops, AND gates, and the like) to perform control
functionality instead of relying upon software.
[0033] Controller 150 can operate upper heating element 118, lower
heating element 119 and/or pump 122 and motor 130 in order to heat
water within interior volume 114 of tank 112. As an example, a user
can select or establish a set-point temperature for water within
interior volume 114 of tank 112, or the set-point temperature for
water within interior volume 114 of tank 112 may be a default
value. Based upon the set-point temperature for water within
interior volume 114 of tank 112, controller 150 can selectively
activate upper heating element 118, lower heating element 119
and/or compressor 122 and motor 130 in order to heat water within
interior volume 114 of tank 112 to the set-point temperature for
water within interior volume 114 of tank 112. The set-point
temperature for water within interior volume 114 of tank 112 can be
any suitable temperature. For example, the set-point temperature
for water within interior volume 114 of tank 112 may be between
about one hundred degrees Fahrenheit and about one hundred and
eighty-degrees Fahrenheit.
[0034] FIGS. 3 through 6 depict various views of an exemplary heat
pump 200 of as may be used with the present subject matter. Thus,
heat pump 200 may be utilized within water heater appliance 100 as
heat pump 126. Heat pump 200 is provided by way of example only and
is not intended to limit the present subject matter to any
particular heat pump. As will be understood, any other suitable
heat pump, such as a linearly actuating heat pump, may be utilized
within water heater appliance 100 as heat pump 126 in alternative
exemplary embodiments.
[0035] Heat pump 200 includes a regenerator housing 202 that
extends longitudinally along an axial direction between a first end
218 and a second end 220. The axial direction is defined by axis
A-A about which regenerator housing 202 is rotatable. A radial
direction R is defined by a radius extending orthogonally from the
axis of rotation A-A (FIG. 5). A circumferential direction is
indicated by arrows C.
[0036] Regenerator housing 202 defines a plurality of chambers 204
that extend longitudinally along the axial direction defined by
axis A-A. Chambers 204 are positioned proximate or adjacent to each
other along circumferential direction C. Each chamber 204 includes
a pair of openings 206 and 208 positioned at opposing ends 218 and
220 of regenerator housing 202.
[0037] Heat pump 200 also includes a plurality of stages 212 that
include MCM. Each stage 212 is located in one of the chambers 204
and extends along the axial direction. For the exemplary embodiment
shown in the figures, heat pump 200 includes eight stages 212
positioned adjacent to each other along the circumferential
direction as shown and extending longitudinally along the axial
direction. As will be understood by one of skill in the art using
the teachings disclosed herein, a different number of stages 212
other than eight may be used as well.
[0038] A pair of valves 214 and 216 is attached to regenerator
housing 202 and rotates therewith along circumferential direction
C. More particularly, a first valve 214 is attached to first end
218 and a second valve 216 is attached to second end 220. Each
valve 214 and 216 includes a plurality of apertures 222 and 224,
respectively. For this exemplary embodiment, apertures 222 and 224
are configured as circumferentially-extending slots that are spaced
apart along circumferential direction C. Each aperture 222 is
positioned adjacent to a respective opening 206 of a chamber 204.
Each aperture 224 is positioned adjacent to a respective opening
208 of a chamber 204. Accordingly, a heat transfer fluid may flow
into a chamber 204 through a respective aperture 222 and opening
206 so as to flow through the MCM in a respective stage 212 and
then exit through opening 208 and aperture 224. A reverse path can
be used for flow of the heat transfer fluid in the opposite
direction through the stage 212 of a given chamber 204.
[0039] Regenerator housing 202 defines a cavity 228 that is
positioned radially inward of the plurality of chambers 204 and
extends along the axial direction between first end 218 and second
end 220. A magnetic element 226 is positioned within cavity 228
and, for this exemplary embodiment, extends along the axial
direction between first end 218 and second end 220. Magnetic
element 226 provides a magnetic field that is directed radially
outward as indicated by arrows M in FIG. 5.
[0040] The positioning and configuration of magnetic element 226 is
such that only a subset of the plurality of stages 212 is within
magnetic field M at any one time. For example, as shown in FIG. 5,
stages 212a and 212e are partially within the magnetic field while
stages 212b, 212c, and 212d are fully within the magnetic field M
created by magnetic element 226. Conversely, the magnetic element
226 is configured and positioned so that stages 212f, 212g, and
212h are completely or substantially out of the magnetic field
created by magnetic element 226. However, as regenerator housing
202 is continuously rotated along the circumferential direction as
shown by arrow W, the subset of stages 212 within the magnetic
field will continuously change as some stages 212 will enter
magnetic field M and others will exit.
[0041] A pair of seals 236 and 238 is provided with the seals
positioned in an opposing manner at the first end 218 and second
end 220 of regenerator housing 202. First seal 236 has a first
inlet port 240 and a first outlet port 242 and is positioned
adjacent to first valve 214. As shown, ports 240 and 242 are
positioned 180 degrees apart about the circumferential direction C
of first seal 214. However, other configurations may be used. For
example, ports 240 and 242 may be positioned within a range of
about 170 degrees to about 190 degrees about the circumferential
direction C as well. First valve 214 and regenerator housing 202
are rotatable relative to first seal 236. Ports 240 and 242 are
connected with lines 160 and 162 (FIG. 2), respectively. As such,
the rotation of regenerator housing 202 about axis A-A sequentially
places lines 160 and 162 in fluid communication with at least two
stages 212 of MCM at any one time as will be further described.
[0042] Second seal 238 has a second inlet port 244 and a second
outlet port 246 and is positioned adjacent to second valve 216. As
shown, ports 244 and 246 are positioned 180 degrees apart about the
circumferential direction C of second seal 216. However, other
configurations may be used. For example, ports 244 and 246 may be
positioned within a range of about 170 degrees to about 190 degrees
about the circumferential direction C as well. Second valve 216 and
regenerator housing 202 are rotatable relative to second seal 238.
Ports 244 and 246 are connected with lines 166 and 164 (FIG. 2),
respectively. As such, the rotation of regenerator housing 202
about axis A-A sequentially places lines 164 and 166 in fluid
communication with at least two stages 212 of MCM at any one time
as will be further described. Notably, at any one time during
rotation of regenerator housing 202, lines 162 and 166 will each be
in fluid communication with at least one stage 212 while lines 160
and 164 will also be in fluid communication with at least one other
stage 212 located about 180 degrees away along the circumferential
direction.
[0043] FIG. 7 illustrates an exemplary method using a schematic
representation of stage 212 of MCM in regenerator housing 202 as it
rotates in the direction of arrow W between positions 1 through 8
as shown in FIG. 6. As will be understood, other suitable
arrangements of heat pump 126 (e.g., linear motion of stages 212 of
MCM) may be utilized to provide similar heating and cooling of the
heat transfer fluid, e.g., via the magneto-caloric effect in stages
212 of MCM. During step 700, stage 212 is fully within magnetic
field M, which causes the magnetic moments of the material to
orient and the MCM to heat as part of the magneto-caloric effect.
Ordering of the magnetic field is created and maintained as stage
212 is rotated sequentially through positions 2, 3, and then 4
(FIG. 6) as regenerator housing 202 is rotated in the direction of
arrow W. During the time at positions 2, 3, and 4, the heat
transfer fluid dwells in the MCM of stage 212 and, therefore, is
heated. More specifically, the heat transfer fluid does not flow
through stage 212 because the openings 206, 208, 222, and 224
corresponding to stage 212 in positions 2, 3, and 4 are not aligned
with any of the ports 240, 242, 244, or 246.
[0044] In step 702, as regenerator housing 202 continues to rotate
in the direction of arrow W, stage 212 will eventually reach
position 5. As shown in FIGS. 3 and 6, at position 5 the heat
transfer fluid can flow through the material as first inlet port
240 is now aligned with an opening 222 in first valve 214 and an
opening 206 at the first end 218 of stage 212 while second outlet
port 246 is aligned with an opening 224 in second valve 216 at the
second end 220 of stage 212. As indicated by arrow Q.sub.H-OUT,
heat transfer fluid in stage 212, now heated by the MCM, can travel
out of regenerator housing 202 and along line 166 to the first heat
exchanger 124. At the same time, and as indicated by arrow
Q.sub.H-IN, heat transfer fluid from second heat exchanger 128
flows into stage 212 from line 164 when stage 212 is at position 5.
Because heat transfer fluid from the second heat exchanger 128 is
relatively cooler than the MCM in stage 212, the MCM rejects heat
to the heat transfer fluid.
[0045] Referring again to FIG. 7 and step 704, as regenerator
housing 202 continues to rotate in the direction of arrow W, stage
212 is moved sequentially through positions 6, 7, and 8 where stage
212 is completely or substantially out of magnetic field M. The
absence or lessening of the magnetic field is such that the
magnetic moments of the material become disordered and the MCM
absorbs heat as part of the magneto-caloric effect. During the time
in positions 6, 7, and 8, the heat transfer fluid dwells in the MCM
of stage 212 and, therefore, is cooled by losing heat to the MCM as
the magnetic moments disorder. More specifically, the heat transfer
fluid does not flow through stage 212 because the openings 206,
208, 222, and 224 corresponding to stage 212 when in positions 6,
7, and 8 are not aligned with any of the ports 240, 242, 244, or
246.
[0046] Referring to step 706 of FIG. 7, as regenerator housing 202
continues to rotate in the direction of arrow W, stage 212 will
eventually reach position 1. As shown in FIGS. 3 and 6, at position
1 the heat transfer fluid in stage 212 can flow through the
material as second inlet port 244 is now aligned with an opening
224 in second valve 216 and an opening 208 at the second end 220
while first outlet port 242 is aligned with an opening 222 in first
valve 214 and opening 206 at first end 218. As indicated by arrow
Q.sub.C-OUT, heat transfer fluid in stage 212, now cooled by the
MCM, can travel out of regenerator housing 202 and along line 162
to the second heat exchanger 128. At the same time, and as
indicated by arrow Q.sub.C-IN, heat transfer fluid from first heat
exchanger 124 flows into stage 212 from line 160 when stage 212 is
at position 5. Because heat transfer fluid from the first heat
exchanger 124 is relatively warmer than the MCM in stage 212 at
position 5, the MCM will be heated by the heat transfer fluid. The
heat transfer fluid now travels along line 162 to the second heat
exchanger 128 to receive additional heat.
[0047] As regenerator housing 202 is rotated continuously, the
above described process of placing stage 212 in and out of magnetic
field M is repeated. Additionally, the size of magnetic field M and
regenerator housing 202 are such that a subset of the plurality of
stages 212 is within the magnetic field at any given time during
rotation. Similarly, a subset of the plurality of stages 212 are
outside (or substantially outside) of the magnetic field at any
given time during rotation. Additionally, at any given time, there
are at least two stages 212 through which the heat transfer fluid
is flowing while the other stages remain in a dwell mode. More
specifically, while one stage 212 is losing heat through the flow
of heat transfer fluid at position 5, another stage 212 is
receiving heat from the flowing heat transfer fluid at position 1,
while all remaining stages 212 are in dwell mode. As such, the
system can be operated continuously to provide a continuous
recirculation of heat transfer fluid in heat pump system 120 as
stages 212 are each sequentially rotated through positions 1
through 8.
[0048] As will be understood by one of skill in the art using the
teachings disclosed herein, the number of stages for housing 202,
the number of ports in valve 214 and 216, and/or other parameters
can be varied to provide different configurations of heat pump 200
while still providing for continuous operation. For example, each
valve could be provided within two inlet ports and two outlet ports
so that heat transfer fluid flows through at least four stages 212
at any particular point in time. Alternatively, regenerator housing
202, valves 222 and 224, and/or seals 236 and 238 could be
constructed so that e.g., at least two stages are in fluid
communication with an inlet port and outlet port at any one time.
Other configurations may be used as well.
[0049] As stated, stage 212 includes MCM extending along the axial
direction of flow. The MCM may be constructed from a single magneto
caloric material or may include multiple different magneto caloric
materials. By way of example, appliance 10 may be used in an
application where the ambient temperature changes over a
substantial range. However, a specific magneto caloric material may
exhibit the magneto caloric effect over only a much narrower
temperature range. As such, it may be desirable to use a variety of
magneto caloric materials within a given stage to accommodate the
wide range of ambient temperatures over which appliance 10 and/or
heat pump 200 may be used.
[0050] A motor 130 is in mechanical communication with regenerator
housing 202 and provides for rotation of housing 202 about axis
A-A. By way of example, motor 130 may be connected directly with
housing 202 by a shaft or indirectly through a gear box. Other
configurations may be used as well.
[0051] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to practice the invention, including making and
using any devices or systems and performing any incorporated
methods. The patentable scope of the invention is defined by the
claims, and may include other examples that occur to those skilled
in the art. Such other examples are intended to be within the scope
of the claims if they include structural elements that do not
differ from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from
the literal languages of the claims.
* * * * *