U.S. patent application number 16/543705 was filed with the patent office on 2020-03-05 for thermomagnetic cycle device.
The applicant listed for this patent is DENSO CORPORATION. Invention is credited to Kentaro KISHI, Yasunori NIIYAMA.
Application Number | 20200072509 16/543705 |
Document ID | / |
Family ID | 69640981 |
Filed Date | 2020-03-05 |
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United States Patent
Application |
20200072509 |
Kind Code |
A1 |
KISHI; Kentaro ; et
al. |
March 5, 2020 |
THERMOMAGNETIC CYCLE DEVICE
Abstract
A device comprises an element bed providing a plurality of unit
channels each containing an NICE element. The heat transport device
has a channel switching mechanism and a biasing mechanism. The
channel switching mechanism forms an inlet valve for allowing the
heat transport medium to flow into the unit channel and an outlet
valve for allowing the heat transport medium to flow out of the
unit channel. The biasing mechanism applies different biasing
forces to the inlet valve and the outlet valve. The magnitude
relationship of the biasing force is the same as the magnitude
relationship between the pressure of the heat transport medium
acting on the inlet valve and the pressure of the heat transport
medium acting on the outlet valve.
Inventors: |
KISHI; Kentaro;
(Kariya-city, JP) ; NIIYAMA; Yasunori;
(Kariya-city, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DENSO CORPORATION |
Kariya-city |
|
JP |
|
|
Family ID: |
69640981 |
Appl. No.: |
16/543705 |
Filed: |
August 19, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 21/00 20130101;
F25B 2321/0021 20130101 |
International
Class: |
F25B 21/00 20060101
F25B021/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 30, 2018 |
JP |
2018-161888 |
Claims
1. A thermomagnetic cycle device comprising: an element bed which
provides a plurality of unit channels each containing an MCE
element demonstrating a magneto caloric effect; a magnetic field
modulation device which modulates a magnetic field applied to the
element bed; and a heat transport device for generating a
reciprocating flow of a heat transport medium which exchanges heat
with the MCE element the heat transport device includes: a
unidirectional pump which flows the heat transport medium; a
channel switching mechanism which forms, at one end and/or the
other end of the unit channel, an inlet valve which allows the heat
transport medium to flow into the unit channel and an outlet valve
which allows the heat transport medium to flow out of the unit
channel; and a biasing mechanism for applying different biasing
forces to the inlet valve and the outlet valve, wherein a magnitude
relationship of the biasing forces is the same as the magnitude
relationship between the pressure of the heat transport medium
acting on the inlet valve and the pressure of the heat transport
medium acting on the outlet valve.
2. The thermomagnetic cycle device claimed in claim 1, wherein the
channel switching mechanism is disposed to oppose the plurality of
unit channels, includes a plurality of segments providing the inlet
valve and the outlet valve, and comprises a valve element which
rotates relative to the plurality of unit channels.
3. The thermomagnetic cycle device claimed in claim 2, wherein the
biasing mechanism generates a pressing force that presses the
element bed and the segment.
4. The thermomagnetic cycle device claimed in claim 1, wherein the
channel switching mechanism includes a plurality of on-off valves
each fixedly arranged in one unit channel and providing the inlet
valve and the outlet valve.
5. The thermomagnetic cycle device claimed in claim 4, wherein the
biasing mechanism adjusts a compression amount of a seal member of
the on-off valve.
6. The thermomagnetic cycle device claimed in claim 1, wherein the
biasing mechanism includes a variable element that varies the
biasing force according to the pressure of the heat transport
medium.
7. The thermomagnetic cycle device claimed in claim 6, wherein the
variable element is a pressure sensitive element whose dimension
changes in accordance with the pressure of the heat transport
medium.
8. The thermomagnetic cycle device claimed in claim 1, wherein the
biasing mechanism includes an invariable element that applies the
biasing force independent of the pressure of the heat transport
medium.
9. The thermomagnetic cycle device claimed in claim 1, wherein the
biasing mechanism includes an elastic member.
10. The thermomagnetic cycle device claimed in claim 1, wherein the
biasing mechanism includes an electromagnetic movable mechanism.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present disclosure is based on Japanese Patent
Application No. 2018461888 filed on Aug. 30, 2018, the whole
contents of which are incorporated herein by reference.
FIELD
[0002] Disclosure in this specification relates to a thermomagnetic
cycle device.
BACKGROUND
[0003] A thermomagnetic cycle device or a magneto-thermal cycle
device utilizes the magneto-thermal properties of a magneto-caloric
element. These devices include a magnetic field modulation device
that periodically changes a magnetic field, and a heat transport
device that creates a reciprocating flow of a heat transport
medium. There is a need for further improvements in thermomagnetic
cycle devices.
SUMMARY
[0004] A thermomagnetic cycle device disclosed comprises: an
element bed which provides a plurality of unit channels each
containing an MCE element that demonstrates a magneto caloric
effect; a magnetic field modulation device which modulates a
magnetic field applied to the element bed; and a heat transport
device for generating a reciprocating flow of a heat transport
medium which exchanges heat with the MCE element. The heat
transport device includes: a unidirectional pump which flows the
heat transport medium; a channel switching mechanism which forms,
at one end and/or the other end of the unit channel, an inlet valve
which allows the heat transport medium to flow into the unit
channel and an outlet valve which allows the heat transport medium
to flow out of the unit channel; and a biasing mechanism for
applying different biasing forces to the inlet valve and the outlet
valve, wherein a magnitude relationship of the biasing forces is
the same as the magnitude relationship between the pressure of the
heat transport medium acting on the inlet valve and the pressure of
the heat transport medium acting on the outlet valve.
[0005] According to the disclosed thermomagnetic cycle device,
different biasing forces are applied to the inlet valve and the
outlet valve by the biasing mechanism. The magnitude relation of
the biasing force is the same as the magnitude relation between the
pressure of the heat transport medium acting on the inlet valve and
the pressure of the heat transport medium acting on the outlet
valve. For example, if the biasing force applied to the inlet valve
is greater than the biasing force applied to the outlet valve, the
pressure of the heat transport medium acting on the inlet valve is
greater than the pressure of the heat transport medium acting on
the outlet valve. For example, if the biasing force applied to the
outlet valve is greater than the biasing force applied to the inlet
valve, the pressure of the heat transport medium acting on the
outlet valve is greater than the pressure of the heat transport
medium acting on the inlet valve. This provides a seal that
withstands the pressure of the heat transport medium at the inlet
valve and the outlet valve. Furthermore, the power for exerting the
biasing force at the inlet valve and the outlet valve is
suppressed. As a result, mechanical loss is suppressed.
[0006] The disclosed aspects in this specification adopt different
technical solutions from each other in order to achieve their
respective objectives. Reference numerals in parentheses described
in claims and this section exemplarily show corresponding
relationships with parts of embodiments to be described later and
are not intended to limit technical scopes. The objects, features,
and advantages disclosed in this specification will become apparent
by referring to following detailed descriptions and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a cross-sectional view of a thermal apparatus
according to a first embodiment;
[0008] FIG. 2 is a cross-sectional view taken along a line II-II of
FIG. 1;
[0009] FIG. 3 is a circuit diagram showing pressure distribution of
a heat transport medium;
[0010] FIG. 4 is an exploded perspective view showing a seal
mechanism at a hot end;
[0011] FIG. 5 is a developed view showing the seal mechanism at the
hot end;
[0012] FIG. 6 is an exploded perspective view showing the seal
mechanism at a cold end;
[0013] FIG. 7 is a developed view of the seal mechanism at the cold
end;
[0014] FIG. 8 is a circuit diagram showing a pressure distribution
according to a second embodiment;
[0015] FIG. 9 is a developed view showing a sealing mechanism;
[0016] FIG. 10 is a development view showing a seal mechanism of a
third embodiment;
[0017] FIG. 11 is a developed view showing a sealing mechanism of a
fourth embodiment;
[0018] FIG. 12 is a developed view showing a seal mechanism of a h
embodiment;
[0019] FIG. 13 is a cross-sectional view of a thermal apparatus
according to a sixth embodiment;
[0020] FIG. 14 is a cross-sectional view taken along a line XIV-XIV
of FIG. 13;
[0021] FIG. 15 is a cross-sectional view taken along a line XV-XV
in FIG. 13;
[0022] FIG. 16 is a cross-sectional view showing an operating state
of a high pressure valve; and
[0023] FIG. 17 is a cross-sectional view showing the operating
state of the low pressure valve.
EMBODIMENT
[0024] Hereinafter, a plurality of embodiments will be described
with reference to the drawings. In some embodiments, parts that are
functionally and/or structurally corresponding and/or associated
are given the same reference numerals, or reference numerals with
different hundred digit or more digits. For corresponding parts
and/or associated parts, reference can be made to the description
of other embodiments.
First Embodiment
[0025] FIG. 1 and FIG. 2 show an air conditioner 1 according to a
first embodiment. FIG. 1 shows a cross section taken along a line
I-I of FIG. 2. FIG. 2 shows a cross section taken along a line
II-II of FIG. 1. The air conditioner 1 is one of thermal devices.
The air conditioner 1 includes a magneto caloric heat pump device
2. The magneto caloric heat pump device 2 is also referred to as an
MHP (Magneto-caloric effect Heat Pump) device 2. The MHP device 2
provides a thermomagnetic cycle device.
[0026] In this specification the term "heat pump device" is used in
a broad sense. That is, the term "heat pump device" includes both a
device utilizing cold energy obtained by the heat pump device and a
device utilizing hot energy obtained by the heat pump device.
Devices that utilize cold energy may also be referred to as
refrigeration cycle devices. Hence, in this specification the term
"heat pump device" is used as a concept encompassing a
refrigeration cycle device.
[0027] The air conditioner 1 has a heat exchanger 3 provided on a
high temperature side, i.e., hot side, of the MHP device 2. The
heat exchanger 3 provides heat exchange between a hot end HT of the
MHP device 2 and a medium, e.g., air. The heat exchanger 3 is
mainly used to radiate heat. In the illustrated example, the heat
exchanger 3 provides heat exchange between the heat transport
medium of the MHP device 2 and the air. The heat exchanger 3 is one
of high temperature system devices in the air conditioner 1. The
heat exchanger 3 is installed, for example, in a room of a vehicle
and heats air by heat exchange with air for air conditioning.
[0028] The air conditioner 1 has a heat exchanger 4 provided on a
low temperature side, i.e., cold side, of the MHP device 2. The
heat exchanger 4 provides heat exchange between a cold end LT of
the MHP device 2 and a medium, e.g., air. The heat exchanger 4 is
mainly used to absorb heat. In the illustrated example, the heat
exchanger 4 provides heat exchange between the heat transport
medium of the MHP device 2 and the heat source medium. The heat
exchanger 4 is one of low temperature system devices in the air
conditioner 1. The heat exchanger 4 is installed, for example,
outside the vehicle and exchanges heat with the outside air.
[0029] The MHP device 2 has a rotary shaft 2a for driving the MHP
device 2. The rotary shaft 2a is operatively connected to a power
source 5. Thus, the MHP device 2 is rotationally driven by the
power source 5. The power source 5 provides rotational power to the
MHP device 2. The power source 5 is the only power source of the
MHP device 2. The power source 5 is provided by a rotary device
such as an electric motor or an internal combustion engine. An
example of a power source is a motor driven by a battery mounted on
a vehicle.
[0030] The MHP device 2 comprises a housing 6. The housing 6
supports the rotary shaft 2a in a rotatable manner. The MHP device
2 includes an element bed 7. The element bed 7 is rotatably
supported in the housing 6. The element bed 7 rotates by receiving
a rotational force directly or indirectly from the rotary shaft 2a.
The element bed 7 is a rotary body rotated by the power source 5.
The element bed 7 is a cylindrical member.
[0031] The element bed 7 forms a working chamber 11 in which the
heat transport medium can flow. One work chamber 11 extends in the
axial direction of the element bed 7. One work chamber 11 is open
at both axial ends of the element bed 7. The element bed 7 may
include a plurality of work chambers 11. The plurality of work
chambers 11 are arranged along the rotational direction of the
element bed 7.
[0032] The element bed 7 has a magneto caloric element 12. The
magneto caloric element 12 is also referred to as a MCE
(Magneto-Caloric Effect) element 12. The MHP device 20 utilizes the
magneto caloric effect of the MCE element 32. The MHP device 2
generates the hot end HT and the cold end LT by the MCE element 12.
The MCE element 12 is provided between the hot end HT and the cold
end LT. In the illustrated example, the right side in the drawing
is the cold end LT, and the left end in the drawing is the hot end
HT. The element bed 7 is also called a rotor. The element bed 7
includes a work chamber 11 and the MCE element 12.
[0033] The MCE element 12 is disposed in the work chamber 11 so as
to exchange heat with the heat transport medium. The MCE element 12
is fixed to and held by the element bed 7. The MCE element 12 is
disposed along the flow direction of the heat transport medium. The
MCE element 12 is elongated along the axial direction of the
element bed 7. The element bed 7 may include a plurality of MCE
elements 12. The plurality of MCE elements 12 are disposed apart
from one another along the rotational direction of the element bed
7.
[0034] The MCE element 12 creates heat generation and heat
adsorption in response to a change of strength of an external
magnetic field. The MCE element 32 creates heat generation by
applying the external magnetic field, and absorbs heat by removing
the external magnetic field. When the electron spins become aligned
in the magnetic field direction by the application of the external
magnetic field, the MCE element 32 demonstrates a decreasing of
magnetic entropy and an increasing of a temperature by releasing
heat. When the electron spins become random by the removal of the
external magnetic field, the MCE element 32 demonstrates an
increasing of the magnetic entropy and a decreasing of a
temperature by absorbing heat. The MCE element 32 is made of a
magnetic material that demonstrates a high magneto caloric effect
in a normal temperature range. For example, gadolinium-based
materials or lanthanum-iron-silicon compounds can be used. Also,
mixtures of manganese, iron, phosphorus and germanium can be used.
As the MCE element 12, an element which absorbs heat by application
of an external magnetic field and generates heat by removal of the
external magnetic field may be used.
[0035] The MHP device 2 has a magnetic field module 8 disposed
opposite to the element bed 7. The magnetic field module 8 is also
called a stator. The magnetic field module 8 is provided by part of
the housing 6. The magnetic field module 8 is disposed on a radial
inside and/or on a radial outside of the element bed 7 and has a
portion radially opposed to the element bed 7. These radially
opposed portions are utilized to provide a magnetic field
modulating device. The magnetic field module 8 is disposed at one
axial end and/or the other axial end of the element bed 7 and has a
portion axially opposed to the element bed 7. These axially opposed
portions are utilized to provide a heat transport device,
specifically, a channel switching mechanism.
[0036] The MHP device 2 includes a magnetic field modulation device
14 and a heat transport device 16 for causing the MCE element 12 to
function as an element of an AMR (Active Magnetic Refrigeration)
cycle. The magnetic field modulation device 14 is provided by the
element bed 7 and the magnetic field module 8. The magnetic field
modulation device 14 periodically increases and decreases the
magnetic field by the relative rotational movement of the element
bed 7 with respect to the magnetic field module 8. The magnetic
field modulation device 14 is driven by the rotational power
applied to the rotary shaft 2a. The fluctuation of the magnetic
field can be created by relatively rotating only one or both of the
element bed 7 and the magnetic field module 8. The element bed 7
provides a movable member. The magnetic field module 8 provides a
stationary member.
[0037] The heat transport device 16 has a pump 17 and a channel
switching mechanism 18. The channel switching mechanism 18 is
provided by the element bed 7 and the magnetic field module 8. The
channel switching mechanism 18 functions by the relative rotational
movement of the element bed 7 with respect to the magnetic field
module 8. The channel switching mechanism 18 switches the flow
direction of the heat transport medium to the work chamber 11 and
the MCE element 12 by switching the connection state of the work
chamber 11 to a channel of the heat transport medium, i.e., a flow
path of the heat transport medium.
[0038] The magnetic field modulation device 14 applies an external
magnetic field to the MCE element 12 and increases or decreases the
strength of the external magnetic field. The magnetic field
modulation device 40 periodically switches between a magnetization
state in which the MCE element 32 is in a strong magnetic field and
a demagnetization state in which the MCE element 32 is in a weak
magnetic field or a zero magnetic field. The magnetic field
modulation device 14 modulates the external magnetic field so as to
alternately and periodically perform a magnetization period AMG in
which the MCE element 12 is placed in a strong external magnetic
field, and a demagnetization period DMG in which the MCE element 12
is placed in an external magnetic field weaker than the
magnetization period AMG. The magnetic field modulation device 14
repeats application and removal of the magnetic field to the MCE
element 12 in synchronization with the reciprocal flow of the heat
transport medium described later. The magnetic field modulation
device 40 comprises a magnetic source, such as a permanent magnet
or an electromagnet, for generating an external magnetic field. The
magnetic source 13 includes an inner magnet 13a located on a radial
inside of the element bed 7. The magnetic source 13 includes an
outer magnet 13b located on a radial outside of the element bed
7.
[0039] Specifically, the magnetic field modulation device 14
alternately positions one work chamber 11 and the MCE element 12 at
the first position and the second position. The magnetic field
modulation device 14 positions the MCE element 12 at the first
position in a strong magnetic field. The magnetic field modulation
device 14 positions the MCE element 12 at the second position in a
weak magnetic field or a zero magnetic field.
[0040] When the heat transport medium flows in a first direction
along the MCE element 12, the magnetic field modulation device 14
positions the MCE element 12 at the first position so that the MCE
element 12 is positioned in the strong magnetic field. The first
direction is a direction from the cold end LT toward the hot end
HT. When one end of the work chamber 11 communicates with a suction
port of the pump 17 and the other end of the work chamber 11
communicates with a discharge port of the pump 17, the magnetic
field modulation device 14 positions the MCE element 12 in the work
chamber 11 at the first position so that the MCE element 12 is
positioned in a strong magnetic field.
[0041] When the heat transport medium flows along the MCE element
12 in a second direction opposite to the first direction, the
magnetic field modulation device 14 positions the MCE element 12 in
the work chamber 11 at the second position so that the MCE element
12 is positioned in a weak magnetic field or a zero magnetic field.
The second direction is a direction from the hot end HT to the cold
end LT. When one end of the work chamber 11 communicates with the
discharge port of the pump 17 and the other end of the work chamber
11 communicates with the suction port of the pump 17, the magnetic
field modulation device 14 positions the MCE element 12 at the
second position so that the MCE element 12 is positioned in a weak
magnetic field or a zero magnetic field.
[0042] The heat transport device 16 includes a heat transport
medium for transporting heat released or absorbed by the MCE
element 12 and a fluid device for flowing the heat transport
medium. The heat transport device 16 is a device for flowing the
heat transport medium along the MCE element 12 which performs
heat-exchange with the MCE element 12. The heat transport device 16
causes the heat transport medium to flow back and forth along the
MCE element 12. The heat transport device 16 generates a
reciprocating flow of the heat transport medium in synchronization
with the change of the external magnetic field by the magnetic
field modulation device 14. The heat transport device 16 switches
the flow direction of the heat transport medium in synchronization
with increase and decrease of the magnetic field by the magnetic
field modulation device 14.
[0043] The heat transport medium which exchanges heat with the MCE
element 12 is called a primary medium. The primary medium can be
provided by a fluid such as antifreeze, water, oil and the like.
The heat transport device 16 comprises the pump 17 for flowing the
heat transport medium. The pump 17 is a unidirectional pump that
flows the heat transport medium in one direction. The pump 17 has a
suction port for sucking the heat transport medium and a discharge
port for discharging the heat transport medium. The pump 17 is
disposed above the annular flow path of the heat transport medium.
The pump 17 produces a unidirectional flow of the heat transport
medium in the annular flow path. The pump 17 is driven by the
rotary shaft 2a. The pump 17 is a positive displacement pump.
[0044] The heat transport device 16 includes a channel switching
mechanism 18. The channel switching mechanism 18 switches the
channel of the heat transport medium to the work chamber 11 so as
to reverse the flow direction of the heat transport medium with
respect to one work chamber 11 and one MCE element 12. In other
words, the channel switching mechanism 18 reverses the arrangement
of the working chamber 11 in the unidirectional flow of the heat
transport medium generated by the unidirectional pump 17 with
respect to the flow direction. The channel switching mechanism 18
alternately positions one working chamber 11 in the forward path
and the return path in an annular flow path including the pump 17.
The channel switching mechanism 18 switches a connection
relationship between a pair of one working chamber 11 and one MCE
element 12 and an annular channel including the pump 17 into at
least two states. In the first state, one end of the work chamber
11 communicates with the suction port of the pump 17, and the other
end of the work chamber 11 communicates with the discharge port of
the pump 17. In the second state, one end of the work chamber 11 is
in communication with the discharge port of the pump 17 and the
other end of the work chamber 11 is in communication with the
suction port of the pump 17.
[0045] Specifically, the channel switching mechanism 18 alternately
positions one work chamber 11 and the MCE element 12 at the first
position and the second position. The channel switching mechanism
18 brings the work chamber 11 accommodating the MCE element 12 into
communication with the flow path so that the heat transport medium
flows in the first direction along the MCE element 12 at the first
position. The channel switching mechanism 18 brings the work
chamber 11 accommodating the MCE element 12 into communication with
the flow path so that the heat transport medium flows in the second
direction opposite to the first direction along the MCE element 12
at the second position. The channel switching mechanism 18 switches
the connection state between the flow path of the heat transport
medium including the pump 17 and the MCE element 12, that is, the
work chamber 11 so that the heat transport medium flows back and
forth to the MCE element 12.
[0046] When one NICE element 12 is in the first position, the
channel switching mechanism 18 communicates the work chamber 11
containing the MCE element 12 and the channel (flow path) so that
the heat transport medium flows in the first direction along the
MCE element 12. When one MCE element 12 is in the first position,
the channel switching mechanism 18 communicates one end of the work
chamber 11 accommodating the NICE element 12 with the suction port
of the pump 17, and communicates the other end of the work chamber
11 accommodating the MCE element 12 with the discharge port of the
pump 17.
[0047] When one MCE element 12 is in the second position, the
channel switching mechanism 18 communicates the work chamber 11
containing the MCE element 12 and the channel (flow path) so that
the heat transport medium flows in the second direction opposite to
the first direction along the MCE element 12. When one MCE element
12 is in the second position, the channel switching mechanism 18
communicates one end of the work chamber 11 accommodating the MCE
element 12 with the discharge port of the pump 17, and communicates
the other end of the work chamber 11 accommodating the MCE element
12 with the suction port of the pump 17.
[0048] The MHP device 2 has a hot end inlet 16a for receiving the
heat transport medium from the heat exchanger 3. The hot end inlet
16a can communicate with the suction port of the pump 17. The MHP
device 2 has a hot end outlet 16b for supplying the heat transport
medium to the heat exchanger 3. The hot end outlet 16b can
communicate with one end of the work chamber 11 at the first
position. The MHP device 2 has a cold end inlet 16c for receiving
the heat transport medium from the heat exchanger 4. The cold end
inlet 16c can communicate with the other end of the work chamber 11
at the first position. The MHP device 2 has a cold end outlet 16d
for supplying the heat transport medium to the heat exchanger 4.
The cold end outlet 16d can communicate with the other end of the
work chamber 11 at the second position. One end of the work chamber
11 at the second position can communicate with the discharge port
of the pump 17.
[0049] The MHP device 2 has a central axis AX. The element bed 7
and the magnetic field module 8 are circular columnar shape or
cylindrical shape with respect to the central axis AX.
[0050] The MHP device 2 includes a controller (CNT) 20. The
controller 20 controls at least the power source 5. The controller
20 controls the number of rotations of the power source 5. In
addition, the controller 20 controls functions as the air
conditioner 1. The controller 20 controls, for example, an amount
of air blown to the heat exchanger 3 and/or the heat exchanger
4.
[0051] The controller 20 is an electronic control unit. The
controller 20 provides a control system for the thermomagnetic
cycle system. The controller 20 has at least one arithmetic
processing unit (CPU) and at least one memory device (MMR) as a
storage medium for storing programs and data. The control system is
provided by a microcomputer comprising a computer readable storage
medium. The storage medium is a non-transitional tangible storage
medium that temporarily stores a computer readable program. The
storage medium may be provided as a semiconductor memory, a
magnetic disk, or the like. The control system may be provided by
one computer or a group of computer resources linked via a data
communication device. The program is executed by the control system
to cause the control system to function as a device described in
the present specification and to cause the control system to
function to perform the methods described in the present
specification.
[0052] Software stored in a tangible memory and a computer
executing the software, only the software, only hardware, or
combination of them may be possible to provide a method and/or
function provided by the control system. For example, the control
system can be provided by a logic called if-then-else type, or a
neural network tuned by machine learning. For example, if the
control system is provided by an electronic circuit that is
hardware, the control device may be provided by a digital circuit
or an analog circuit that includes a large number of logic
circuits.
[0053] FIG. 3 shows a pressure distribution of the heat transport
medium. The MHP device 2 provides a circulation path for the heat
transport medium. The pump 17 is disposed in a circulation path.
Furthermore, the channel switching mechanism 18 is disposed in a
flow path extending between the element bed 7 and the magnetic
field module 8, that is, between the movable member and the
stationary member. The channel switching mechanism 18 has a
plurality of valves. A plurality of valves are arranged at the
inlet and the outlet of the plurality of element beds 7. Here, in
order to make the explanation easy to understand, two unit channels
(element bed 7) providing circulation paths and four related valves
will be described. The channel switching mechanism 18 has at least
an inlet valve 18a and an outlet valve 18b at the hot end HT. The
channel switching mechanism 18 has at least the outlet valve 18e
and the inlet valve 18f at the cold end LT.
[0054] The heat exchanger 3 produces a pressure drop PDe. The heat
exchanger 4 also produces a pressure drop PDe. The heat exchanger 3
and the heat exchanger 4 may produce different pressure losses. The
pump 17 sucks the heat transport medium at a suction pressure Ps.
The pump 17 pressurizes the heat transport medium. The pump 17
discharges the heat transport medium of the discharge pressure Pd.
The unit channel (element bed 7) produces a pressure loss PDd.
[0055] The heat transport medium is supplied at a pressure P1
toward one unit channel. At this time, the pressure P1 acts on the
inlet valve 18a. The seal mechanism provided by the inlet valve 18a
provides a seal that can function properly under the pressure P1.
The heat transport medium flows out of one unit channel at a
pressure P2. The pressure P2 acts on the outlet valve 18e. The seal
mechanism provided by the outlet valve 18e provides a seal that can
function properly under the pressure P2.
[0056] The pressure P1 is higher than the pressure P2 (P1>P2).
Therefore, the inlet valve 18a is required to have higher sealing
performance than the outlet valve 18e. On the contrary, the outlet
valve 18e can perform proper function with a sealing property lower
than that of the inlet valve 18a. In other words, even if the
pressing force between the stationary member and the movable member
in the outlet valve 18e is smaller than the pressing force between
the stationary member and the movable member in the inlet valve
18a, the outlet valve 18e can perform proper function. The inlet
valve 18a and the outlet valve 18e provide an inlet and an outlet
for the flow of the heat transport medium in one direction of the
reciprocating flow. One direction is a direction from the hot end
HT to the cold end LT. The inlet valve 18a and the outlet valve 18e
provide an inlet and an outlet associated with the common unit
channel (element bed 7).
[0057] The heat transport medium is supplied at a pressure P3
toward one unit channel. At this time, the pressure P3 acts on the
inlet valve 18f. The seal mechanism provided by the inlet valve 18f
provides a seal that can function properly under the pressure P3.
The heat transport medium flows out of one unit channel at a
pressure P4. The pressure P4 acts on the outlet valve 18b. The
sealing mechanism provided by the outlet valve 18b provides a seal
that can function properly under the pressure P4.
[0058] The pressure P3 is higher than the pressure P4 (P3>P4).
Therefore, the inlet valve 18f is required to have higher sealing
performance than the outlet valve 18b. On the contrary, the outlet
valve 18b can perform proper function with a sealing property lower
than that of the inlet valve 18f. In other words, even if the
pressing force between the stationary member and the movable member
in the outlet valve 18b is smaller than the pressing force between
the stationary member and the movable member in the inlet valve
18f, the outlet valve 18b can perform proper function. The inlet
valve 18f and the outlet valve 18b provide an inlet and an outlet
for the flow of the heat transport medium in the other direction of
the reciprocating flow. The other direction is a direction from the
cold end LT to the hot end HT. The inlet valve 18f and the outlet
valve 18b provide an inlet and an outlet associated with a common
unit channel (element bed 7).
[0059] Focusing on the hot end HT or the cold end LT, at least a
pair of an inlet valve and an outlet valve is disposed between the
stationary member and the movable member. The channel switching
mechanism 18 can include an even number of pairs of inlet and
outlet valves. In this embodiment, two pairs of inlet and outlet
valves are arranged as described below.
[0060] At one end, i.e., the hot end HT, the pressure P1 is higher
than the pressure P4 (P1>P4). Therefore, the inlet valve 18a is
required to have higher sealing performance than the outlet valve
18b. On the contrary, the outlet valve 18b can perform proper
function with lower sealing performance than that of the inlet
valve 18a. In other words, even if the pressing force between the
stationary member and the movable member in the outlet valve 18b is
smaller than the pressing force between the stationary member and
the movable member in the inlet valve 18a, the outlet valve 18b can
perform proper function. In this embodiment, the pressing force F1
at the inlet valve 18a is larger than the pressing force F2 at the
outlet valve 18d (F1>F2). Thereby, the mechanical loss in the
outlet valve 18b is suppressed.
[0061] The inlet valve 18a and the outlet valve 18b provide an
inlet and an outlet for the reciprocating flow at one end, i.e.,
the hot end HT. The inlet valve 18a provides an inlet for the flow
from the hot end HT to the cold end LT. The outlet valve 18b
provides an outlet for the flow from the cold end LT to the hot end
HT. The inlet valve 18a and the outlet valve 18b simultaneously
provide an inlet and an outlet associated with different unit
channels.
[0062] At the other end, i.e., at the cold end LT, the pressure P2
is higher than the pressure P3 (P2>P3). For this reason, the
outlet valve 18e is required to have higher sealing performance
than that of the inlet valve 18f. On the contrary, the inlet valve
18f can perform proper function with a lower sealing performance
than that of the outlet valve 18e. In other words, even if the
pressing force between the stationary member and the movable member
in the inlet valve 18f is smaller than the pressing force between
the stationary member and the movable member in the outlet valve
18e, the inlet valve 18f can perform proper function. In this
embodiment, the pressing force F5 at the outlet valve 18e is larger
than the pressing force F6 at the inlet valve 18f (F5>F6).
Thereby, the mechanical loss in the inlet valve 18f is
suppressed.
[0063] The inlet valve 18f and the outlet valve 18e provide an
inlet and an outlet for the reciprocating flow at the other end,
i.e., the cold end LT. The inlet valve 18 f provides an inlet for
flow from the cold end LT to the hot end HT. The outlet valve 18e
provides an outlet for the flow from the hot end HT to the cold end
LT. The inlet valve 18f and the outlet valve 18e provide an inlet
and an outlet associated with different unit channels.
[0064] FIGS. 4 and 5 show the channel switching mechanism 18 at the
hot end HT and the sealing mechanism associated therewith. The work
chamber 11 provided by the element bed 7 provides a plurality of
axial flow channels. In the drawing, one unit channel is
illustrated by a mass of the MCE element 12. The name "one element
bed 7" may refer to this unit channel.
[0065] The channel switching mechanism 18 includes a valve element
19 disposed opposite to the element bed 7 which is a movable
member. The valve element 19 is a stationary member. The valve
element 19 is disposed opposite to the end of the element bed 7.
The valve element 19 comes in contact with the end face of the
element bed 7 in a sliding manner. The valve element 19 provides a
plurality of ports for providing the inlet valve 18a and the outlet
valve 18b. The valve element 19 comprises a plurality of segments
19a, 19b, 19c and 19d. The plurality of segments 19a, 19b, 19c and
19d are annularly arranged. Each of the plurality of segments 19a,
19b, 19c and 19d occupies a fan-shaped area. The plurality of
segments 19a, 19b, 19c and 19d are held so as to be relatively
movable in the axial direction. The plurality of segments 19a, 19b,
19c and 19d are held immovable in the circumferential
direction.
[0066] The segment 19a provides the inlet valve 18a. The inlet
valve 18a opens to the unit channel when the segment 19a and the
unit channel are opposed to each other. The inlet valve 18a closes
to the unit channel when the segment 19a and the unit channel do
not face each other and are separated. The segment 19b provides an
outlet valve 18b. The outlet valve 18b opens to the unit channel
when the segment 19b and the unit channel are opposed to each
other. The outlet valve 18b closes with respect to the unit channel
when the segment 19b and the unit channel do not face each other
and are separated. As a result, the channel switching mechanism 18
forms the inlet valve 18a and the outlet valve 18b at one end of
one unit channel. In this embodiment, two inlet valves and two
outlet valves are provided by the four segments 19a, 19b, 19c and
19d. Thus, the channel switching mechanism 18 forms two inlet
valves and two outlet valves at one end of one unit channel. The
two inlet valves 18a and 18c and the two outlet valves 18b and 18d
are alternately opened and closed with respect to one unit channel
to provide the reciprocating flow.
[0067] The channel switching mechanism 18 has the biasing mechanism
30 for pressing the valve element 19 toward the element bed 7. The
biasing mechanism 30 provides at least two different biasing
forces. In this embodiment, the biasing force is also called
pressing force. The biasing mechanism 30 has four biasing elements
31, 32, 33 and 34 associated with each of the four segments 19a,
19b, 19c and 19d. In this embodiment, the segments 19a and 19c may
be biased by a common biasing element since they provide the inlet
valves. Similarly, the segments 19b and 19d may be biased by a
common biasing element to provide the outlet valves.
[0068] Each of the biasing elements 31, 32, 33 and 34 has a
variable element 35 and an invariable element 36. The variable
element 35 varies the biasing force according to the pressure of
the heat transport medium. The variable element 35 is provided by a
pressure sensitive element whose dimension, i.e., axial length,
varies in response to the pressure of the heat transport medium.
The variable element 35 is provided by a balloon. The variable
element 35 axially expands under the pressure of the heat transport
medium when the pressure of the heat transport medium exceeds the
predetermined pressure. The variable element 35 contracts in the
axial direction under the pressure of the heat transport medium
when the pressure of the heat transport medium falls below a
predetermined pressure. The predetermined pressure can be set
between the pressure P1 and the pressure P4. The invariable element
36 is an elastic member that provides invariable resiliency. The
invariable element 36 generates a biasing force without depending
on a pressure of the heat transport medium. The invariable element
36 can be provided, for example, by a mechanical coil spring. The
invariable element 36 is a preloaded compression coil spring.
[0069] When the pressure P1 acts on the variable element 35, the
variable element 35 elongates in the axial direction. As a result,
the segment 19a is pressed toward the element bed 7 by the pressing
force F1. The pressing force F1 produces a surface pressure that
provides sealing between the segment 19a and the element bed 7.
When the pressure P4 acts on the variable element 35, the variable
element 35 comes in contract in the axial direction. As a result,
the segment 19b is pressed toward the element bed 7 by the pressing
force F2. The pressing force F2 produces a surface pressure that
provides sealing between the segment 19b and the element bed 7. The
pressing force F1 is larger than the pressing force F2
(F1>F2).
[0070] When the element bed 7, which is a movable member, rotates,
the unit channel sequentially passes over the plurality of segments
19a, 19b, 19c, and 19d. When the unit channel is located above the
segments 19a and 19c, the segments 19a and 19c are pressed toward
the element bed 7 by the pressing force F1. When the unit channel
is located above the segments 19b and 19d, the segments 19b and 19d
are pressed toward the element bed 7 with the pressing force F2. As
a result, compared with the case where the entire valve element 19
is pressed toward the element bed 7 by the pressing force F1, the
pressing force is suppressed in the section of the segments 19b and
19d. As a result, mechanical loss is suppressed.
[0071] FIGS. 6 and 7 show the channel switching mechanism 18 at the
cold end LT and the sealing mechanism associated therewith. The
valve element 19 provides a plurality of ports for providing the
inlet valve 18f and the outlet valve 18e. The valve element 19
comprises a plurality of segments 19e, 19f, 19g and 19h.
[0072] The segment 19e provides the outlet valve 18e. The outlet
valve 18e opens to the unit channel when the segment 19e and the
unit channel are opposed to each other. The outlet valve 18e closes
to the unit channel when the segment 19e and the unit channel do
not face each other and are separated. The segment 19f provides the
inlet valve 18f. The inlet valve 18f opens to the unit channel when
the segment 19f and the unit channel are opposed to each other. The
inlet valve 18f closes to the unit channel when the segment 19f and
the unit channel do not face each other and are separated. As a
result, the channel switching mechanism 18 forms the outlet valve
18e and the inlet valve 18f at the other end of one unit channel.
In this embodiment, two inlet valves 18f and 18h and two outlet
valves 18e and 18g are provided by four segments 19e, 19f, 19g and
19h. Thus, the channel switching mechanism 18 forms two inlet
valves and two outlet valves on the other end of one unit channel.
The two inlet valves and the two outlet valves are alternately
opened and closed with respect to one unit channel to provide the
reciprocating flow. The channel switching mechanism 18 at the hot
end HT and the channel switching mechanism 18 at the cold end LT
are arranged symmetrically to each other.
[0073] At the cold end LT, the predetermined pressure of the
variable element 35 is set between the pressure P2 and the pressure
P3. When the pressure P2 acts on the variable element 35, the
variable element 35 elongates in the axial direction. As a result,
the segments 19e and 19g are pressed toward the element bed 7 by
the pressing force F5. The pressing force F5 produces a surface
pressure that provides sealing between the segments 19e and 19g and
the element bed 7. When the pressure P3 acts on the variable
element 35, the variable element 35 comes contract in the axial
direction. As a result, the segments 19f and 19h are pressed toward
the element bed 7 by the pressing force F6. The pressing force F6
produces a surface pressure that provides sealing between the
segments 19f and 19h and the element bed 7. The pressing force F5
is larger than the pressing force F6 (F5>F6). Even in the cold
end LT, the pressing force is suppressed in a section of the
segments 19f and 19h as compared with the case where the entire
valve element 19 is pressed toward the element bed 7 by the
pressing force F5. As a result, mechanical loss is suppressed.
[0074] With regard to the MHP device 2, the description of
JP2016-1101A may be referred to. The entire contents of
JP2016-1101A are incorporated by reference. Further, with regard to
the element bed 7 and the unit channel, U.S. Pat. No. 8,844,453 may
be referred to. The entire contents of U.S. Pat. No. 8,444,453 are
incorporated by reference. According to the embodiment described
above, the channel switching mechanism 18 forms the inlet valve 18a
and the outlet valve 18b at one end (the hot end HT) of one unit
channel. The biasing mechanism 30 provides biasing force for
maintaining the inlet valve 18a and the outlet valve 18b in the
closed state. Moreover, the biasing mechanism 30 applies different
biasing forces F1 and F2 to the inlet valve 18a and the outlet
valve 18b. The magnitude relationship (F1>F2) of the two biasing
forces is the same as the magnitude relationship (P1>P4) between
the pressure P1 of the heat transport medium acting on the inlet
valve 18a and the pressure P4 of the heat transport medium acting
on the outlet valve 18b.
[0075] Furthermore, the absolute value of the biasing force is
adjusted by the variable element 35. Moreover, the biasing force is
set in proportion to the pressure. For this reason, the
valve-closing performance which withstands the pressure of the heat
transport medium, i.e., sealing performance, is obtained.
[0076] The channel switching mechanism 18 forms the inlet valve 18f
and the outlet valve 18e at the other end (the cold end LT) of one
unit channel. The biasing mechanism 30 provides a biasing force for
maintaining the inlet valve 18f and the outlet valve 18e in a
closed state. Moreover, the biasing mechanism 30 applies different
biasing forces F5 and F6 to the inlet valve 18f and the outlet
valve 18e. The magnitude relationship (F5>F6) of the two biasing
forces is the same as the magnitude relationship (P2>P3) between
the pressure P3 of the heat transport medium acting on the inlet
valve 18f and the pressure P2 of the heat transport medium acting
on the outlet valve 18e.
[0077] As a result, mechanical loss can be suppressed. Moreover,
the valve element 19 comprises a plurality of segments. The
multiple segments allow different pressing forces and reliably
suppress mechanical losses.
Second Embodiment
[0078] This embodiment is a modification in which the preceding
embodiment is a fundamental form. In the above embodiment, the MHP
device 2 has a single pump 17. Alternatively, the MHP device 2 may
be provided with a plurality of pumps 17 and 217a. The pump 17 is
provided at one end of the unit channel. The pump 217a is provided
at the other end of the unit channel.
[0079] FIG. 8 shows pressure distribution in this embodiment. The
MHP device 2 also has a pump 217a in a path on a side to the cold
end LT. The pump 17 and the pump 217a are the same pump. The pump
217a applies a pressure P2a to the outlet valve 18e. The pump 217a
applies a pressure P3a to the inlet valve 18f.
[0080] In this case, the pressure P2a acting on the outlet valve
18e is higher than the pressure P3a acting on the inlet valve 18f.
For this reason, the inlet valve 18f is required to have higher
sealing performance than that of the outlet valve 18e. On the
contrary, the outlet valve 18e can perform proper function with a
sealing property lower than that of the inlet valve 18f. In other
words, even if the pressing force between the stationary member and
the movable member in the outlet valve 18e is smaller than the
pressing force between the stationary member and the movable member
in the inlet valve 18f, the outlet valve 18e can perform proper
function. In this embodiment, the pressing force F6a at the inlet
valve 18f is larger than the pressing force F5a at the outlet valve
18e (F5a<F6a). Thereby, the mechanical loss in the outlet valve
18e is suppressed. The inlet valve 18f and the outlet valve 18e
provide an inlet and an outlet for the reciprocating flow at the
other end, i.e, the cold end LT. The inlet valve 18f provides an
inlet for flow from the cold end LT to the hot end HT. The outlet
valve 18e provides an outlet for the flow from the hot end HT to
the cold end LT. The inlet valve 18f and the outlet valve 18e are
positioned opposite to different element beds 7.
[0081] FIG. 9 shows the channel switching mechanism 18 at the cold
end LT and the sealing mechanism associated therewith. A difference
from the preceding embodiments is the shape of the variable element
35 and the pressing forces F5a and F6a produced thereby. When the
biasing mechanism 30 includes the variable element 35, a difference
in pressing force occurs. The segments 19e and 19g are pressed
toward the element bed 7 by the pressing force F5a. The segments
19f and 19h are pressed toward the element bed 7 by the pressing
force F6a. The pressing force F6a is larger than the pressing force
F5a (F5a<F6a).
[0082] According to this embodiment, the channel switching
mechanism 18 forms the inlet valve 18f and the outlet valve 18e at
the other end (the cold end LT) of one unit channel. The biasing
mechanism 30 provides a biasing force for maintaining the inlet
valve 18f and the outlet valve 18e in a closed state. Moreover, the
biasing mechanism 30 applies different biasing forces F5 and F6 to
the inlet valve 18f and the outlet valve 18e. The magnitude
relationship (F5a<F6a) of the two biasing forces is the same as
the magnitude relationship (P2a<P3a) between the pressure P3a of
the heat transport medium acting on the inlet valve 18f and the
pressure P2a of the heat transport medium acting on the outlet
valve 18e. As a result, even if the pump 217a is provided,
mechanical loss is suppressed.
Third Embodiment
[0083] This embodiment is a modification in which the preceding
embodiment is a fundamental form. In the above embodiment, the
biasing elements 31, 32, 33, 34 comprise both the variable element
35 and the invariable element 36. Alternatively, the biasing
elements 31, 32, 33, 34 may comprise only the invariable element
36.
[0084] In FIG. 10, the functions of the plurality of segments 19a,
19b, 19c and 19d are fixed at the inlet or outlet. For example, the
segment 19a continuously provides an inlet. The segment 19b
continuously provides an exit. For this reason, the pressing force
to be applied to the plurality of segments may be fixed. The
biasing elements 31, 32, 33 and 34 then comprise only the
invariable element 36. The invariable element 36 includes a first
elastic member 336a for generating a pressing force F1 and a second
elastic member 336b for generating a pressing force F2. The first
elastic member 336a and the second elastic member 336b can be
provided by coil springs having different spring constants or
compression amounts. The first elastic member 336a and the second
elastic member 336b are compression coil springs which are
preloaded differently to generate the pressing forces F1 and F2.
The first elastic member 336a applies the pressing force F1
stronger than the pressing force F2 to the segments 19a and 19c.
The second elastic member 336b applies the pressing force F2 weaker
than the pressing force F1 to the segments 19b and 19d. The biasing
elements 31 and 33 each comprises a first resilient member 336a.
The biasing elements 32 and 34 each comprises a second resilient
member 336b. In this embodiment as well, similar to the previous
embodiments, mechanical losses can be suppressed. The structure of
this embodiment can be adopted for the hot end HT and/or the cold
end LT.
Fourth Embodiment
[0085] This embodiment is a modification in which the preceding
embodiment is a fundamental form. In the above embodiment, a coil
spring is used as the invariable element 36. Alternatively, the
invariable element may be provided by a variety of elastic members.
For example, a resin material such as rubber or elastomer may be
used as the invariable element.
[0086] In FIG. 11, the invariable element 36 includes a first
elastic member 436a for generating a pressing force F1 and a second
elastic member 436b for generating a pressing force F2. The first
elastic member 436a and the second elastic member 436b can be
provided by rubber masses different in elasticity. In this
embodiment as well, similar to the previous embodiments, mechanical
losses can be suppressed.
Fifth Embodiment
[0087] This embodiment is a modification in which the preceding
embodiment is a fundamental form. In the above embodiment, the
variable element 35 is provided by a mechanical element.
Alternatively, the variable element 35 may be provided by a variety
of variable mechanisms. For example, an electromagnetic movable
mechanism can be used as a variable element.
[0088] In FIG. 12, the variable element 35 is provided by an
electromagnetic solenoid. The electromagnetic solenoid includes a
stator 537 that includes an electromagnetic coil. The
electromagnetic solenoid includes an armature 538 that contracts
when it is attracted by the electromagnetic force generated by
exiting the stator 537, and extends when it is freed by a spring
force by de-energizing the stator 537. The armature 538 is
connected to the invariable element 36. The electromagnetic
solenoid can be controlled by the controller 20. In this embodiment
as well, similar to the previous embodiments, mechanical losses can
be suppressed.
Sixth Embodiment
[0089] This embodiment is a modification in which the preceding
embodiment is a fundamental form. In the above embodiment, the
movable member is provided by the element bed 7, and the stationary
member is provided by the magnetic field module 8. Alternatively,
the element bed 7 may provide a stationary member, and the magnetic
field module 8 may provide a movable member.
[0090] FIG. 13, FIG. 14 and FIG. 15 show the air conditioner 1 and
the MHP device 2 of this embodiment. FIG. 13 shows a cross section
taken along a line XIII-XIII in FIG. 14 and FIG. 15. FIG. 14 shows
a cross section taken along a line XIV-XIV of FIG. 13. FIG. 15
shows a cross section taken along a line XV-XV in FIG. 13.
[0091] In FIG. 13, the MHP device 2 includes the element bed 7, the
magnetic field modulation device 14, and the heat transport device
16. The element bed 7 accommodates the MCE element 12. The element
bed 7 provides a plurality of unit channels. The magnetic field
modulation device 14 supplies an external magnetic field to the
element bed 7. The magnetic field modulation device 14 modulates an
intensity of the external magnetic field so that the MCE element 12
alternately demonstrates heat generation and heat absorption by the
magneto caloric effect. The heat transport device 16 provides a
reciprocating flow of the heat transport medium to perform a heat
exchange with the MCE element 12. The magnetic field modulation
device 14 and the heat transport device 16 are synchronized with
each other. The MHP device 2 is operated to provide an AMR
cycle.
[0092] The magnetic field modulation device 14 is provided by the
element bed 7 and the magnetic field module 8. The element bed 7 is
a stationary member. The element bed 7 is also called a stator. The
magnetic field module 8 is a movable member. The magnetic field
module 8 is also called a rotor. The magnetic field module 8 has an
inner magnet 613a and an outer magnet 613b as the magnetic source
13. The inner magnet 613a is fixed to an inner yoke 608a that
rotates with the rotary shaft 2a. The outer magnet 613b is fixed to
an outer yoke 608b that rotates with the rotary shaft 2a.
[0093] The channel switching mechanism 18 includes a switching
valve. The switching valve is disposed in the body 618k fixed to
the element bed 7. The body 618k is a part of a stationary member.
The switching valve is provided by a plurality of on-off valves.
The switching valve includes two sets of on-off valves disposed at
both ends of one unit channel. One set of on-off valves includes an
inlet valve 618a and an outlet valve 618b. In FIG. 13, two unit
channels are exemplarily illustrated, and four sets of eight on-off
valves are illustrated.
[0094] FIG. 14 shows a plurality of unit channels provided by the
element bed 7. The plurality of unit channels are illustrated as a
first channel #1 to an eighth channel #8. The number of unit
channels illustrated is merely an example, and is not limited to
eight.
[0095] In this embodiment, the channels from the first channel #1
to the eighth channel #8 are stationary. The magnetic source 613
rotationally moves. With the movement of the magnetic source 613,
the magnetization period AMG and the demagnetization period DMG
move. As a result, one unit channel is alternately placed in the
magnetization period AMG and the demagnetization period DMG. For
example, at the time of illustration, the first channel #1 is
positioned in the magnetization period AMG, and the second channel
#2 is positioned in the demagnetization period DMG. When the
magnetic source 13 rotates by n/2 from the time shown, the first
channel #1 is positioned in the demagnetization period DMG, and the
second channel #2 is positioned in the magnetization period
AMG.
[0096] FIG. 15 shows a plurality of sets of on-off valves
associated with a plurality of unit channels at the hot end HT. The
symbol "=" indicates the close state. The symbol " " and the symbol
"X" indicate the open state. The symbol " " indicates the direction
of flow from the paper surface. The symbol "X" indicates the
direction of flow toward the paper surface.
[0097] In this embodiment, the element bed 7 provides eight unit
channels. The channel switching mechanism 18 has eight sets of
on-off valves. For example, the inlet valve 618a and the outlet
valve 618b are associated with the hot end HT of the first channel
#1. Similarly, the inlet valve 618a and the outlet valve 618b are
associated with the hot end HT of the second channel #2.
[0098] The plurality of sets of on-off valves are driven to open
and close so as to supply a reciprocating flow in the plurality of
unit channels. Switching between valve opening and valve closing is
synchronized with switching between the magnetization period AMG
and the demagnetization period DMG. The plurality of on-off valves
are driven by the plurality of cam mechanisms 618m and 618n. The
switching of the flow direction of the reciprocating flow and the
switching of the magnetization period AMG and the demagnetization
period DMG may be adjusted in phase by the phase adjuster.
[0099] One set of two on-off valves, i.e., the inlet valve 618a and
the outlet valve 618b, are alternately opened and closed. For
example, the outlet valve 618b is closed while the inlet valve 618a
of the first channel #1 is open. While the inlet valve 618a of the
first channel #1 is closed, the outlet valve 618b is opened.
Further, the open/close states of the inlet valve 618a and the
outlet valve 618b are alternately switched. For example, at the
time shown, the inlet valve 618a of the first channel #1 positioned
in the magnetization period AMG is opened and the outlet valve 618b
is closed. Thus, the channel switching mechanism 18 supplies the
flow of the heat transport medium in the first direction to the
first channel #1. When the magnetic source 13 rotates by .pi./2
from the illustrated time point, the inlet valve 618a of the first
flow path #1 positioned in the demagnetization period DMG is closed
and the outlet valve 618b is opened. Thus, the channel switching
mechanism 18 supplies the flow of the heat transport medium in the
second direction opposite to the first direction to the first
channel #1.
[0100] Returning to FIG. 13, the channel switching mechanism 18
includes a mechanical link mechanism for driving the switching
valve by the rotary shaft 2a. The mechanical link mechanism has a
plurality of cam mechanisms 618m and 618n. The plurality of cam
mechanisms 618m and 618n drive four on-off valves arranged on both
sides of one unit channel so as to alternately switch the flow
direction of the heat transport medium.
[0101] The plurality of cam mechanisms 618m and 618n drive the
plurality of on-off valves alternately and complementarily. The
term "alternating" refers to the inlet valve 618a and the outlet
valve 618b being alternately opened and closed. The term
"complementary" refers to the relative relationship between the
on-off valve at the hot end HT and the on-off valve at the cold end
LT. That is, the term "complementary" indicates switching between
the following state (1) and the following state (2). In the state
of (1), the inlet valve 618a of the hot end HT and the outlet valve
618b of the cold end LT are simultaneously opened, and the inlet
valve 618a of the cold end LT and the outlet valve 618b of the hot
end HT are simultaneously closed. In the state of (2), the inlet
valve 618a of the cold end LT and the outlet valve 618b of the hot
end HT are simultaneously opened, and the inlet valve 618a of the
hot end HT and the outlet valve 618b of the cold end LT are
simultaneously closed.
[0102] The cam mechanism 618m produces a first stroke ST1. The cam
mechanism 618m drives the inlet valve 618a. The inlet valve 618a is
switched between the open state and the closed state by the first
stroke ST1. The cam mechanism 618n produces a second stroke ST2.
The cam mechanism 618n drives the outlet valve 618b. The outlet
valve 618b is switched between the open state and the closed state
by the second stroke ST2. The first stroke ST1 is larger than the
second stroke ST2 (ST1>ST2). The difference between the first
stroke ST1 and the second stroke ST2 is used as the difference in
the compression amount of the seal member described later.
[0103] Also in this embodiment, pressure distribution occurs in the
flow path due to the position of the pump 17 and the pressure loss
of each part. The pressure P1 acts on the inlet valve 618a of the
hot end HT. On the other hand, the pressure P4 acts on the outlet
valve 618b of the hot end HT. The pressure P1 is higher than the
pressure P4. The force for the outlet valve 618b to maintain the
closed state against the pressure P4 is smaller than the force for
the inlet valve 618a to maintain the closed state against the
pressure P1. Thus, by adjusting the force applied to the outlet
valve 618b to be smaller than the force applied to the inlet valve
618a, mechanical losses are suppressed.
[0104] FIG. 16 shows the on-off valve as the inlet valve 618a at
the hot end HT. FIG. 17 shows the on-off valve as the outlet valve
618b at the hot end HT. In FIGS. 16 and 17, the inlet valve 618a
and the outlet valve 618b have a housing 641, ports 642 and 643,
seal members 644a and 644b, a plunger 645, a cam follower 646, a
rod 647, and a movable flange 648. The housing 641 provides ports
642 and 643 used as an inlet and an outlet. The housing 641
accommodates the seal members 644a and 644b and the plunger 645.
The seal members 644a and 644b are fixed in the housing 641. The
plunger 645 is relatively movable within the housing 641. The cam
follower 646 comes in contact with the cam surfaces of the cam
mechanisms 618m and 618n. The rod 647 transmits the movement of the
cam follower 646 to the plunger 645. The movable flange 648 seals
between the housing 641 and the rod 647. The movable flange 648 is
provided by a bellows or a diaphragm.
[0105] In FIG. 16, the inlet valve 618a at the hot end HT provides
an open state OPN and a close state CLSa. The inlet valve 618a
provides the open state OPN by the plunger 645 moving away from the
seal member 644a. The seal member 644a in the open state OPN has an
initial length L1. The inlet valve 618a provides a closed state
CLSa by the plunger 645 contacting the seal member 644a and the
plunger 645 compressing the seal member 644a. The compression
amount CA1 of the seal member 644a in the close state CLSa is
defined by the initial length L1 and the first stroke ST1. The
amount of compression CA1 is the amount of compression necessary
for the inlet valve 618a at the hot end HT to maintain a closed
state under the pressure P1 of the heat transport medium. The close
state CLSa is also referred to as a first close state CLSa. The
compression amount CA1 is also referred to as a first compression
amount CAL
[0106] In FIG. 17, the outlet valve 618b at the hot end HT provides
an open state OPN and a close state CLSb. The outlet valve 618b
provides the open state OPN by the plunger 645 separating from the
seal member 644b. The seal member 644b in the open state OPN has an
initial length L2. The initial length L2 is smaller than the
initial length L1 (L1>L2). In the outlet valve 618b, the plunger
645 comes in contact with the seal member 644b, and the plunger 645
compresses the seal member 644b to provide the close state CLSb.
The compression amount CA2 of the seal member 644b in the close
state CLSb is defined by the initial length L2 and the second
stroke ST2. The compression amount CA2 is a compression amount
required for the outlet valve 618b at the hot end HT to maintain a
closed state under the pressure P4 of the heat transport medium.
The close state CLSb is also referred to as a second close state
CLSb. The compression amount CA2 is also referred to as a second
compression amount CA2.
[0107] In FIGS. 16 and 17, the first compression amount CA1 is
larger than the second compression amount CA2 (CA1>CA2). As a
result, the inlet valve 618a withstands the pressure P1, and the
outlet valve 618b withstands the pressure P4. At the same time, the
power for compressing the seal member 644b at the outlet valve 618b
is suppressed. In this embodiment, the biasing mechanism 30 is
provided by the initial lengths L1 and L2 of the sealing members
644a and 644b and the strokes ST1 and ST2 of the cam mechanisms
618m and 618n. This suppresses mechanical losses.
[0108] In this embodiment, the plurality of on-off valves and the
biasing mechanism 30 at the hot end HT have been described in
detail. This description may also be applied to the plurality of
on-off valves and the biasing mechanism 30 at the cold end LT.
[0109] In FIG. 13, the MHP device 2 also has a channel switching
mechanism 18 at the cold end LT. The channel switching mechanism 18
of the hot end HT and the channel switching mechanism 18 of the
cold end LT are arranged symmetrically. For example, the outlet
valve 618e and the inlet valve 618f are associated with the cold
end LT of the first channel #1. Similarly, the outlet valve 618e
and the inlet valve 618f are associated with the cold end LT of the
second channel #2.
[0110] The plurality of pressure distributions described in the
first and second embodiments are also applicable to this
embodiment. That is, also in this embodiment, the pump can be
disposed at the cold end LT. When the pump is not disposed at the
cold end LT, the inlet valve 618f of the cold end LT can be
provided based on FIG. 17, and the outlet valve 618e of the cold
end LT can be provided based on FIG. 16. When the pump is disposed
at the cold end LT, the inlet valve 618f of the cold end LT can be
provided based on FIG. 16, and the outlet valve 618e of the cold
end LT can be provided based on FIG. 17.
[0111] In the sixth embodiment, the biasing mechanism 30 creates
the difference (CA1-CA2) of the compression amount of the seal
members 644a and 644b by the difference of the initial length
(L1-L2), and the difference between the strokes (ST1-ST2).
Alternatively, the biasing mechanism 30 may create the difference
in the amount of compression only by the difference in the initial
length. Furthermore, the biasing mechanism 30 may create the
difference in the amount of compression only by the difference in
the stroke.
[0112] Also in this embodiment, the channel switching mechanism 18
forms an inlet valve 618a and an outlet valve 618b at one end of
one unit channel. The biasing mechanism 30 provides biasing force
for maintaining the inlet valve 18a and the outlet valve 18b in the
close state. Moreover, the biasing mechanism 30 applies different
biasing forces F1 and F2 to the inlet valve 18a and the outlet
valve 18b. The magnitude relationship (F1>F2) of the two biasing
forces is the same as the magnitude relationship (P1>P4) between
the pressure P1 of the heat transport medium acting on the inlet
valve 18a and the pressure P4 of the heat transport medium acting
on the outlet valve 18b.
[0113] Patent Documents JP2012-229634A, JP2016-1101A, and U.S. Pat.
No. 8,448,453 discloses prior art arrangements. In those
arrangements, a sealing mechanism is required to suppress leakage
of the heat transport medium. However, the sealing mechanism
produces mechanical losses. The mechanical loss appears as a loss
of power to drive the movable member. For this reason, the
thermomagnetic cycle device with small mechanical loss is required.
In one form, for example, the heat transport medium may flow
through both the movable member and the stationary member. In this
case, the sealing mechanism between the movable member and the
stationary member creates a mechanical loss. In another form, for
example, an on-off valve that controls the flow of the heat
transport medium may be disposed in the movable member or the
stationary member. In this case, the sealing mechanism of the
on-off valve produces mechanical losses. Furthermore, when the
pressure of the heat transport medium in the sealing mechanism
fluctuates, a period in which the pressure difference to be sealed
is large and a period in which the pressure difference to be sealed
is small occur. In this case, the sealing mechanism is designed to
withstand periods of high pressure differential to seal. However,
in this design, it is difficult to suppress mechanical loss
throughout the unit cycle.
[0114] The disclosed embodiments in this specification provide a
thermomagnetic cycling device with low mechanical loss. The
disclosed embodiments in this specification also provide a
thermomagnetic cycle device in which mechanical loss in the heat
transport device is suppressed.
OTHER EMBODIMENTS
[0115] The disclosure in this specification, the drawings, and the
like is not limited to the illustrated embodiments. The disclosure
encompasses the illustrated embodiments and variations thereof by
those skilled in the art. For example, the disclosure is not
limited to the parts and/or combinations of elements shown in the
embodiments. The disclosure can be implemented in various
combinations. The disclosure may have additional parts that may be
added to the embodiment. The disclosure encompasses omissions of
parts and/or elements of the embodiments. The disclosure
encompasses replacement or combination of parts and/or elements
between one embodiment and another. The disclosed technical scope
is not limited to the description of the embodiment. Several
technical scopes disclosed are indicated by descriptions in the
claims and should be understood to include all modifications within
the meaning and scope equivalent to the descriptions in the
claims.
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