U.S. patent application number 14/509303 was filed with the patent office on 2016-04-14 for capillary tube for a packaged terminal air conditioner unit.
The applicant listed for this patent is General Electric Company. Invention is credited to Joel Erik Hitzelberger, Brent Alden Junge, Michael John Kempiak.
Application Number | 20160102898 14/509303 |
Document ID | / |
Family ID | 55655207 |
Filed Date | 2016-04-14 |
United States Patent
Application |
20160102898 |
Kind Code |
A1 |
Junge; Brent Alden ; et
al. |
April 14, 2016 |
CAPILLARY TUBE FOR A PACKAGED TERMINAL AIR CONDITIONER UNIT
Abstract
A capillary tube for a heat pump system, such as a packaged
terminal air conditioner unit, includes features for adjusting a
restriction on a flow of refrigerant through the capillary tube
depending upon a direction of the flow of refrigerant through the
capillary tube. A related packaged terminal air conditioner unit is
also provided.
Inventors: |
Junge; Brent Alden;
(Evansville, IN) ; Kempiak; Michael John;
(Osceola, IN) ; Hitzelberger; Joel Erik;
(Louisville, KY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company |
Schenectady |
NY |
US |
|
|
Family ID: |
55655207 |
Appl. No.: |
14/509303 |
Filed: |
October 8, 2014 |
Current U.S.
Class: |
62/528 ;
62/324.6 |
Current CPC
Class: |
F25B 41/067 20130101;
F25B 2341/061 20130101; F25B 2341/062 20130101 |
International
Class: |
F25B 41/06 20060101
F25B041/06; F25B 41/04 20060101 F25B041/04 |
Claims
1. A packaged terminal air conditioner unit, comprising: a casing
extending between an exterior side portion and an interior side
portion; a compressor positioned within the casing, the compressor
operable to compress a refrigerant; an interior coil positioned
within the casing at the interior side portion of the casing; an
exterior coil positioned within the casing at the exterior side
portion of the casing; a reversing valve in fluid communication
with the compressor in order to receive compressed refrigerant from
the compressor, the reversing valve configured for selectively
directing the compressed refrigerant from the compressor to either
the interior coil or the exterior coil; a capillary tube extending
between the interior coil and the exterior coil in order to direct
refrigerant between the interior coil and the exterior coil, the
capillary tube comprising means for adjusting a restriction on a
flow of refrigerant through the capillary tube depending upon a
direction of the flow of refrigerant through the capillary
tube.
2. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the capillary tube
defining an interior volume for directing the flow of refrigerant
through the capillary tube, the means for adjusting the restriction
comprising a wire positioned within the interior volume of the
capillary tube at the first end portion of the capillary tube.
3. The packaged terminal air conditioner unit of claim 2, wherein
the wire is mounted to the capillary tube at the first end portion
of the capillary tube.
4. The packaged terminal air conditioner unit of claim 2, wherein
the capillary tube and the wire are bent at the first end portion
of the capillary tube in order to hinder movement of the wire
within the interior volume of the capillary tube.
5. The packaged terminal air conditioner unit of claim 2, wherein
the capillary tube and the wire are constructed of copper.
6. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the means for adjusting
the restriction comprising a crimp defined by the capillary tube at
the first end portion of the capillary tube.
7. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the means for adjusting
the restriction comprising a fixed restriction orifice positioned
at the first end portion of the capillary tube.
8. The packaged terminal air conditioner unit of claim 7, wherein
the fixed restriction orifice is brazed or interference fit onto
the capillary tube at the first end portion of the capillary
tube.
9. The packaged terminal air conditioner unit of claim 7, wherein
the fixed restriction orifice is brazed or interference fit onto a
jumper tube of the exterior coil.
10. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the means for adjusting
the restriction comprising a plurality of coils defined by the
capillary tube at the first end portion of the capillary tube.
11. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the capillary tube
defining an interior volume for directing the flow of refrigerant
through the capillary tube, the means for adjusting the restriction
comprising a flow washer positioned within the interior volume of
the capillary tube at the first end portion of the capillary
tube.
12. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the capillary tube
defining an interior volume for directing the flow of refrigerant
through the capillary tube, the means for adjusting the restriction
comprising a plurality of conical segments defined by an inner
surface of the capillary tube proximate at the first end portion of
the capillary tube.
13. The packaged terminal air conditioner unit of claim 12, wherein
each conical segment of the plurality of conical segments expands
along an axial direction defined between the first and second end
portions of the capillary tube.
14. The packaged terminal air conditioner unit of claim 1, wherein
the capillary tube extends between a first end portion and a second
end portion, the first end portion of the capillary tube positioned
adjacent the exterior coil, the second end portion of the capillary
tube positioned adjacent the interior coil, the capillary tube
defining an interior volume for directing the flow of refrigerant
through the capillary tube, the means for adjusting the restriction
comprising a piston disposed within the interior volume of the
capillary tube at the first end portion of the capillary tube, the
piston slidable within the interior volume between a first position
and a second position, the piston obstructing more refrigerant flow
through the interior volume of the capillary tube in the first
position than in the second position.
15. A packaged terminal air conditioner unit, comprising: a casing;
a compressor positioned within the casing, the compressor operable
to increase a pressure of a refrigerant; a reversing valve
positioned within the casing, the reversing valve in fluid
communication with the compressor in order to receive compressed
refrigerant from the compressor; an interior coil positioned within
the casing; an exterior coil positioned within the casing opposite
the interior coil, the interior coil and the exterior coil in fluid
communication with the reversing valve such that either the
interior coil or the exterior coil receive the compressed
refrigerant from the reversing valve; and a capillary tube
extending between the interior coil and the exterior coil in order
to direct refrigerant between the interior coil and the exterior
coil, the capillary tube extending between a first end portion and
a second end portion, the first end portion of the capillary tube
positioned adjacent the exterior coil, the second end portion of
the capillary tube positioned adjacent the interior coil, the
capillary tube defining an interior volume for directing the flow
of refrigerant through the capillary tube; and a block positioned
within the interior volume of the capillary tube at the first end
portion of the capillary tube such that the block occupies a
portion of the interior volume of the tubular body at the first end
portion of the tubular body.
16. The packaged terminal air conditioner unit of claim 15, wherein
the block is mounted to the capillary tube at the first end portion
of the capillary tube.
17. The packaged terminal air conditioner unit of claim 15, wherein
the capillary tube and the block are bent at the first end portion
of the capillary tube in order to hinder movement of the block
within the interior volume of the capillary tube.
18. The packaged terminal air conditioner unit of claim 15, wherein
the capillary tube and the block are constructed of copper.
19. The packaged terminal air conditioner unit of claim 15, wherein
the capillary tube is constructed of a first material and the block
is constructed of a second material, the first and second material
being different.
20. A capillary tube for a heat pump system, comprising: a tubular
body extending between a first end portion and a second end
portion, the tubular body defining an interior volume for directing
a flow of refrigerant through the tubular body, cross-sections of
the interior volume of the tubular body being substantially
constant between the first and second end portions of the tubular
body; a block positioned within the interior volume of the tubular
body at the first end portion of the tubular body such that the
block occupies a portion of the interior volume of the tubular body
at the first end portion of the tubular body.
Description
FIELD OF THE INVENTION
[0001] The present subject matter relates generally to heat pump
systems, such as packaged terminal air conditioner units, and
capillary tubes for the same.
BACKGROUND OF THE INVENTION
[0002] Certain heat pump systems include a sealed system for
chilling and/or heating air with refrigerant. The sealed systems
generally include a throttling device for restricting a flow of
refrigerant between an outdoor coil and an indoor coil of the
sealed system. Various throttling devices are available, including
capillary tubes, J-T valves, electronic expansion valves, etc.
Electronic expansion valves can offer functional advantages over
other throttling devices. In particular, electronic expansion
valves can be adjusted to vary the restriction on refrigerant
flowing through the electronic expansion valves.
[0003] Packaged terminal air conditioner units generally include a
casing and a sealed system. Due to space constraints within the
casing, selection of sealed system components for packaged terminal
air conditioner units can be limited. For example, electronic
expansion valves can be bulky and occupy a large volume within the
casing. Thus, utilizing electronic expansion valves within packaged
terminal air conditioner units can be difficult despite functional
advantages provided by electronic expansion valves. Electronic
expansion valves can also be costly.
[0004] Accordingly, a packaged terminal air conditioner unit with
features for providing variable restriction on refrigerant flowing
through a throttling device of the packaged terminal air
conditioner unit would be useful. In particular, a packaged
terminal air conditioner unit with a throttling device that
includes features for providing variable restriction on refrigerant
flowing through the throttling device that also occupies little
space within a casing of the packaged terminal air conditioner unit
would be useful.
BRIEF DESCRIPTION OF THE INVENTION
[0005] The present subject matter provides a capillary tube for a
heat pump system, such as a packaged terminal air conditioner unit.
The capillary tube includes features for adjusting a restriction on
a flow of refrigerant through the capillary tube depending upon a
direction of the flow of refrigerant through the capillary tube. A
related packaged terminal air conditioner unit is also provided.
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 packaged terminal air
conditioner unit is provided. The packaged terminal air conditioner
unit includes a casing that extends between an exterior side
portion and an interior side portion. A compressor is positioned
within the casing. The compressor is operable to increase a
pressure of a refrigerant. An interior coil is positioned within
the casing at the interior side portion of the casing. An exterior
coil is positioned within the casing at the exterior side portion
of the casing. A reversing valve is in fluid communication with the
compressor in order to receive compressed refrigerant from the
compressor. The reversing valve is configured for selectively
directing the compressed refrigerant from the compressor to either
the interior coil or the exterior coil. A capillary tube extends
between the interior coil and the exterior coil in order to direct
refrigerant between the interior coil and the exterior coil. The
capillary tube includes means for adjusting a restriction on a flow
of refrigerant through the capillary tube depending upon a
direction of the flow of refrigerant through the capillary
tube.
[0007] In a second exemplary embodiment, a packaged terminal air
conditioner unit is provided. The packaged terminal air conditioner
unit includes a casing. A compressor is positioned within the
casing. The compressor is operable to increase a pressure of a
refrigerant. A reversing valve is positioned within the casing. The
reversing valve is in fluid communication with the compressor in
order to receive compressed refrigerant from the compressor. An
interior coil is positioned within the casing. An exterior coil is
positioned within the casing opposite the interior coil. The
interior coil and the exterior coil are in fluid communication with
the reversing valve such that either the interior coil or the
exterior coil receives the compressed refrigerant from the
reversing valve. A capillary tube extends between the interior coil
and the exterior coil in order to direct refrigerant between the
interior coil and the exterior coil. The capillary tube extends
between a first end portion and a second end portion. The first end
portion of the capillary tube is positioned adjacent the exterior
coil. The second end portion of the capillary tube is positioned
adjacent the interior coil. The capillary tube defines an interior
volume for directing the flow of refrigerant through the capillary
tube. A block is positioned within the interior volume of the
capillary tube at the first end portion of the capillary tube such
that the block occupies a portion of the interior volume of the
tubular body at the first end portion of the tubular body.
[0008] In a third exemplary embodiment, a capillary tube for a heat
pump system is provided. The capillary tube includes a tubular body
extending between a first end portion and a second end portion. The
tubular body defines an interior volume for directing a flow of
refrigerant through the tubular body. Cross-sections of the
interior volume of the tubular body are substantially constant
between the first and second end portions of the tubular body. A
block is positioned within the interior volume of the tubular body
at the first end portion of the tubular body such that the block
occupies a portion of the interior volume of the tubular body at
the first end portion of the tubular body.
[0009] 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
[0010] 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.
[0011] FIG. 1 provides an exploded perspective view of a packaged
terminal air conditioner unit according to an exemplary embodiment
of the present subject matter.
[0012] FIG. 2 provides a schematic view of certain components of
the exemplary packaged terminal air conditioner unit of FIG. 1.
[0013] FIG. 3 provides a perspective view of a capillary tube
according to an exemplary embodiment of the present subject
matter.
[0014] FIG. 4 provides a perspective view of a capillary tube
according to an additional exemplary embodiment of the present
subject matter.
[0015] FIG. 5 provides an exploded perspective view of a capillary
tube according another exemplary embodiment of the present subject
matter.
[0016] FIG. 6 provides a perspective view of a capillary tube
according still another exemplary embodiment of the present subject
matter.
[0017] FIG. 7 provides a perspective view of a capillary tube
according yet another exemplary embodiment of the present subject
matter.
[0018] FIGS. 8 and 9 provide partial section views of the exemplary
capillary tube of FIG. 7 and a flow washer of the exemplary
capillary tube.
[0019] FIG. 10 provides a section view of a capillary tube
according yet another additional exemplary embodiment of the
present subject matter.
[0020] FIGS. 11 and 12 provide schematic views of a capillary tube
according still another additional exemplary embodiment of the
present subject matter.
[0021] FIG. 13 provides a perspective view of a capillary tube
according an additional exemplary embodiment of the present subject
matter.
[0022] FIGS. 14 and 15 provide section views of the exemplary
capillary tube of FIG. 13.
[0023] FIGS. 16 and 17 provide section views of the exemplary
capillary tube of FIG. 13 in another exemplary embodiment.
DETAILED DESCRIPTION
[0024] 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.
[0025] FIG. 1 provides an exploded perspective view of a packaged
terminal air conditioner unit 100 according to an exemplary
embodiment of the present subject matter. Packaged terminal air
conditioner unit 100 is operable to generate chilled and/or heated
air in order to regulate the temperature of an associated room or
building. As will be understood by those skilled in the art,
packaged terminal air conditioner unit 100 may be utilized in
installations where split heat pump systems are inconvenient or
impractical. As discussed in greater detail below, a sealed system
120 of packaged terminal air conditioner unit 100 is disposed
within a casing 110. Thus, packaged terminal air conditioner unit
100 may be a self-contained or autonomous system for heating and/or
cooling air.
[0026] As may be seen in FIG. 1, casing 110 extends between an
interior side portion 112 and an exterior side portion 114.
Interior side portion 112 of casing 110 and exterior side portion
114 of casing 110 are spaced apart from each other. Thus, interior
side portion 112 of casing 110 may be positioned at or contiguous
with an interior atmosphere, and exterior side portion 114 of
casing 110 may be positioned at or contiguous with an exterior
atmosphere. Sealed system 120 includes components for transferring
heat between the exterior atmosphere and the interior atmosphere,
as discussed in greater detail below.
[0027] Casing 110 defines a mechanical compartment 116. Sealed
system 120 is disposed or positioned within mechanical compartment
116 of casing 110. A front panel 118 and a rear grill or screen 119
are mounted to casing 110 and hinder or limit access to mechanical
compartment 116 of casing 110. Front panel 118 is mounted to casing
110 at interior side portion 112 of casing 110, and rear screen 119
is mounted to casing 110 at exterior side portion 114 of casing
110. Front panel 118 and rear screen 119 each define a plurality of
holes that permit air to flow through front panel 118 and rear
screen 119, with the holes sized for preventing foreign objects
from passing through front panel 118 and rear screen 119 into
mechanical compartment 116 of casing 110.
[0028] Packaged terminal air conditioner unit 100 also includes a
drain pan or bottom tray 138 and an inner wall 140 positioned
within mechanical compartment 116 of casing 110. Sealed system 120
is positioned on bottom tray 138. Thus, liquid runoff from sealed
system 120 may flow into and collect within bottom tray 138. Inner
wall 140 may be mounted to bottom tray 138 and extend upwardly from
bottom tray 138 to a top wall of casing 110. Inner wall 140 limits
or prevents air flow between interior side portion 112 of casing
110 and exterior side portion 114 of casing 110 within mechanical
compartment 116 of casing 110. Thus, inner wall 140 may divide
mechanical compartment 116 of casing 110.
[0029] Packaged terminal air conditioner unit 100 further includes
a controller 146 with user inputs, such as buttons, switches and/or
dials. Controller 146 regulates operation of packaged terminal air
conditioner unit 100. Thus, controller 146 is in operative
communication with various components of packaged terminal air
conditioner unit 100, such as components of sealed system 120
and/or a temperature sensor, such as a thermistor or thermocouple,
for measuring the temperature of the interior atmosphere. In
particular, controller 146 may selectively activate sealed system
120 in order to chill or heat air within sealed system 120, e.g.,
in response to temperature measurements from the temperature
sensor.
[0030] Controller 146 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
packaged terminal air conditioner unit 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 146 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.
[0031] FIG. 2 provides a schematic view of certain components of
packaged terminal air conditioner unit 100, including sealed system
120. Sealed system 120 generally operates in a heat pump cycle.
Sealed system 120 includes a compressor 122, an interior heat
exchanger or coil 124 and an exterior heat exchanger or coil 126.
As is generally understood, various conduits may be utilized to
flow refrigerant between the various components of sealed system
120. Thus, e.g., interior coil 124 and exterior coil 126 may be
between and in fluid communication with each other and compressor
122.
[0032] As may be seen in FIG. 2, sealed system 120 also includes a
reversing valve 132. Reversing valve 132 selectively directs
compressed refrigerant from compressor 122 to either interior coil
124 or exterior coil 126. For example, in a cooling mode, reversing
valve 132 is arranged or configured to direct compressed
refrigerant from compressor 122 to exterior coil 126. Conversely,
in a heating mode, reversing valve 132 is arranged or configured to
direct compressed refrigerant from compressor 122 to interior coil
124. Thus, reversing valve 132 permits sealed system 120 to adjust
between the heating mode and the cooling mode, as will be
understood by those skilled in the art.
[0033] During operation of sealed system 120 in the cooling mode,
refrigerant flows from interior coil 124 flows through compressor
122. For example, refrigerant may exit interior coil 124 as a fluid
in the form of a superheated vapor. Upon exiting interior coil 124,
the refrigerant may enter compressor 122. Compressor 122 is
operable to compress the refrigerant. Accordingly, the pressure and
temperature of the refrigerant may be increased in compressor 122
such that the refrigerant becomes a more superheated vapor.
[0034] Exterior coil 126 is disposed downstream of compressor 122
in the cooling mode and acts as a condenser. Thus, exterior coil
126 is operable to reject heat into the exterior atmosphere at
exterior side portion 114 of casing 110 when sealed system 120 is
operating in the cooling mode. For example, the superheated vapor
from compressor 122 may enter exterior coil 126 via a first
distribution conduit 134 that extends between and fluidly connects
reversing valve 132 and exterior coil 126. Within exterior coil
126, the refrigerant from compressor 122 transfers energy to the
exterior atmosphere and condenses into a saturated liquid and/or
liquid vapor mixture. An exterior air handler or fan 150 is
positioned adjacent exterior coil 126 may facilitate or urge a flow
of air from the exterior atmosphere across exterior coil 126 in
order to facilitate heat transfer.
[0035] Sealed system 120 also includes a capillary tube 128
disposed between interior coil 124 and exterior coil 126, e.g.,
such that capillary tube 128 extends between and fluidly couples
interior coil 124 and exterior coil 126. Refrigerant, which may be
in the form of high liquid quality/saturated liquid vapor mixture,
may exit exterior coil 126 and travel through capillary tube 128
before flowing through interior coil 124. Capillary tube 128 may
generally expand the refrigerant, lowering the pressure and
temperature thereof. The refrigerant may then be flowed through
interior coil 124.
[0036] Interior coil 124 is disposed downstream of capillary tube
128 in the cooling mode and acts as an evaporator. Thus, interior
coil 124 is operable to heat refrigerant within interior coil 124
with energy from the interior atmosphere at interior side portion
112 of casing 110 when sealed system 120 is operating in the
cooling mode. For example, the liquid or liquid vapor mixture
refrigerant from capillary tube 128 may enter interior coil 124 via
a second distribution conduit 136 that extends between and fluidly
connects interior coil 124 and reversing valve 132. Within interior
coil 124, the refrigerant from capillary tube 128 receives energy
from the interior atmosphere and vaporizes into superheated vapor
and/or high quality vapor mixture. An interior air handler or fan
148 is positioned adjacent interior coil 124 may facilitate or urge
a flow of air from the interior atmosphere across interior coil 124
in order to facilitate heat transfer.
[0037] During operation of sealed system 120 in the heating mode,
reversing valve 132 reverses the direction of refrigerant flow
through sealed system 120. Thus, in the heating mode, interior coil
124 is disposed downstream of compressor 122 and acts as a
condenser, e.g., such that interior coil 124 is operable to reject
heat into the interior atmosphere at interior side portion 112 of
casing 110. In addition, exterior coil 126 is disposed downstream
of capillary tube 128 in the heating mode and acts as an
evaporator, e.g., such that exterior coil 126 is operable to heat
refrigerant within exterior coil 126 with energy from the exterior
atmosphere at exterior side portion 114 of casing 110.
[0038] Appropriate restriction of refrigerant within capillary tube
128 may assist with efficiently operating sealed system 120.
However, the appropriate restriction may change depending upon
whether sealed system 120 is operating in the cooling mode or the
heating mode and the direction of refrigerant flow through
capillary tube 128. As discussed in greater detail below, various
features of capillary tube 128 may vary the restriction on
refrigerant flowing through capillary tube 128 depending upon the
direction of refrigerant flow through capillary tube 128.
[0039] As discussed above, when the refrigerant enters capillary
tube 128, refrigerant is mostly or all liquid and is typically
subcooled below the saturation temperature. The restriction of
capillary tube 128 can directly correspond to the amount of vapor
phase refrigerant within the flow of refrigerant through capillary
tube 128 and/or the amount of subcooled liquid phase refrigerant
within the flow of refrigerant through capillary tube 128. As the
refrigerant flows through capillary tube 128, the refrigerant
pressure decreases and refrigerant vapor bubbles form. Without
wishing to be bound to any particular theory, the refrigerant vapor
bubbles are of a much lower density than the liquid refrigerant and
the refrigerant vapor bubbles displace liquid refrigerant and
restrict mass flow. The present subject matter may assist with
decreasing refrigerant mass flow in one direction, e.g., by
increasing restriction of the refrigerant when the refrigerant is a
vapor without having much of an effect when the refrigerant is a
liquid flowing in the opposite direction.
[0040] It should be understood that sealed system 120 may include
more capillary tubes between interior coil 124 and exterior coil
126 in alternative exemplary embodiments. For example, 120 sealed
system 120 may include a pair of capillary tubes 128 plumbed in
parallel between interior coil 124 and exterior coil 126. The pair
of capillary tubes 128 may assist with more easily receiving
refrigerant from when exterior coil 126 has two outlets and
interior coil 124 has two inlets, in the cooling mode. In such
exemplary embodiments, each capillary tube may have a different
restriction in order to optimize or improve flow within interior
coil 124 and/or exterior coil 126.
[0041] FIG. 3 provides a perspective view of a capillary tube 200
according to an exemplary embodiment of the present subject matter.
Capillary tube 200 may be used in any suitable heat pump system.
For example, capillary tube 200 may be used in packaged terminal
air conditioner unit 100 as capillary tube 128 of sealed system 120
(FIG. 2). As discussed in greater detail below, capillary tube 200
includes features for adjusting a restriction on a flow of
refrigerant through capillary tube 200 depending upon a direction
of the flow of refrigerant through capillary tube 200.
[0042] As may be seen in FIG. 3, capillary tube 200 is a generally
tubular body, such as a copper or aluminum pipe. Capillary tube 200
extends between a first end portion 202 and a second end portion
204. First end portion 202 of capillary tube 200 may be positioned
adjacent and/or mounted to exterior coil 126 of sealed system 120.
Second end portion 204 of capillary tube 200 may be positioned
adjacent and/or mounted to interior coil 124 of sealed system 120.
Capillary tube 200 also defines an interior volume 206, e.g., that
extends between first and second end portions 202, 206 of capillary
tube 200, for directing the flow of refrigerant through capillary
tube 200.
[0043] Capillary tube 200 also includes a wire or block 210
positioned within interior volume 206 of capillary tube 200 at or
adjacent first end portion 202 of capillary tube 200. Block 210
occupies a portion of interior volume 206 of capillary tube 200 at
first end portion 202 of capillary tube 200. As may be seen in FIG.
3, interior volume 206 of capillary tube 200 may have a generally
constant cross-sectional area between first and second end portions
202, 206 of capillary tube 200. By occupying the portion of
interior volume 206 of capillary tube 200 at first end portion 202
of capillary tube 200, block 210 can adjust the restriction on the
flow of refrigerant through capillary tube 200 depending upon a
direction of the flow of refrigerant through capillary tube 200.
For example, by occupying the portion of interior volume 206 of
capillary tube 200 at first end portion 202 of capillary tube 200,
the restriction on the flow of refrigerant when sealed system 120
is operating in the heating mode is greater than when sealed system
120 is operating in the cooling mode. In particular, refrigerant
enters capillary tube 200 as a liquid and at least a portion of the
refrigerant transforms to a vapor while passing through capillary
tube 200. When vapor phase refrigerant passes through first end
portion 202 of capillary tube 200, block 210 restricts refrigerant
flow to a greater degree than when liquid phase refrigerant passes
through first end portion 202 of capillary tube 200, e.g., due to
the lower density of vapor phase refrigerant which can increase the
velocity of the flow of refrigerant through capillary tube 200.
[0044] Block 210 may be constructed of or with any suitable
material, e.g., that does not react with or corrode in the presence
of the refrigerant within capillary tube 200. For example,
capillary tube 200 and block 210 may be constructed with common
materials, such as copper or aluminum. In alternative exemplary
embodiments, capillary tube 200 and block 210 may be constructed
with different materials.
[0045] Block 210 may be mounted to capillary tube 200 at first end
portion 202 of capillary tube 200 in certain exemplary embodiments.
Thus, block 210 may be static or fixed within capillary tube 200.
For example, capillary tube 200 and/or block 210 may be bent at
first end portion 202 of capillary tube 200 in order to hinder or
limit movement of block 210 within interior volume 206 of capillary
tube 200. As another example, block 210 may be brazed, glued or
fastened to capillary tube 200 at first end portion 202 of
capillary tube 200.
[0046] As may be seen in FIG. 3, capillary tube 200 defines a
length L between first and second end portions 202, 204 of
capillary tube 200. Block 210 may also define a length within
interior volume 206 of capillary tube 200. The length of block 210
may be less than the length L of capillary tube 200. For example,
the length of block 210 may be no greater than half the length L of
capillary tube 200. As another example, the length of block 210 may
be no greater than a quarter of the length L of capillary tube 200.
As yet another example, the length of block 210 may be no greater
than a tenth of the length L of capillary tube 200.
[0047] FIG. 4 provides a perspective view of a capillary tube 300
according to an additional exemplary embodiment of the present
subject matter. Capillary tube 300 may be used in any suitable heat
pump system. For example, capillary tube 300 may be used in
packaged terminal air conditioner unit 100 as capillary tube 128 of
sealed system 120 (FIG. 2). As discussed in greater detail below,
capillary tube 300 includes features for adjusting a restriction on
a flow of refrigerant through capillary tube 300 depending upon a
direction of the flow of refrigerant through capillary tube
300.
[0048] Capillary tube 300 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 300 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 300 extends between a first end portion 302 and a
second end portion 304 and defines an interior volume 306 for
directing the flow of refrigerant through capillary tube 300.
[0049] Capillary tube 300 also includes a crimp 310 defined by
capillary tube 300 at or adjacent first end portion 302 of
capillary tube 300. Crimp 310 is formed by capillary tube 300 such
that crimp 310 reduces the cross-sectional area of interior volume
306 of capillary tube 300 at crimp 310. As may be seen in FIG. 4,
interior volume 306 of capillary tube 300 may have a generally
constant cross-sectional area between first and second end portions
302, 304 of capillary tube 300 except for crimp 310.
[0050] By reducing the cross-sectional area of interior volume 306
of capillary tube 300 at first end portion 302 of capillary tube
300, crimp 310 can adjust the restriction on the flow of
refrigerant through capillary tube 300 depending upon a direction
of the flow of refrigerant through capillary tube 300, e.g., in the
same or similar manner to block 210 (FIG. 3) described above. For
example, by reducing the cross-sectional area of interior volume
306 of capillary tube 300 at first end portion 302 of capillary
tube 300, the restriction on the flow of refrigerant when sealed
system 120 is operating in the heating mode is greater than when
sealed system 120 is operating in the cooling mode.
[0051] Crimp 310 may be formed in any suitable manner on capillary
tube 300. For example, a clamp or roller may plastically deform
capillary tube 300 in order to form crimp 310 at first end portion
302 of capillary tube 300. Crimp 310 may be formed on capillary
tube 300 such that crimp 310 extends uniformly about capillary tube
300 in certain exemplary embodiments.
[0052] As may be seen in FIG. 4, capillary tube 300 defines a
length L between first and second end portions 302, 304 of
capillary tube 300. Crimp 310 also defines a length CL on capillary
tube 300. The length CL of crimp 310 may be less than the length L
of capillary tube 300. For example, the length CL of crimp 310 may
be no greater than a tenth of the length L of capillary tube
300.
[0053] FIG. 5 provides an exploded perspective view of a capillary
tube 400 according another exemplary embodiment of the present
subject matter. Capillary tube 400 may be used in any suitable heat
pump system. For example, capillary tube 400 may be used in
packaged terminal air conditioner unit 100 as capillary tube 128 of
sealed system 120 (FIG. 2). As discussed in greater detail below,
capillary tube 400 includes features for adjusting a restriction on
a flow of refrigerant through capillary tube 400 depending upon a
direction of the flow of refrigerant through capillary tube
400.
[0054] Capillary tube 400 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 400 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 400 extends between a first end portion 402 and a
second end portion 404 and defines an interior volume 406 for
directing the flow of refrigerant through capillary tube 400.
[0055] Capillary tube 400 also includes a fixed restriction orifice
410 positioned at or adjacent first end portion 402 of capillary
tube 400. Fixed restriction orifice 410 may be a cylindrical disk
that defines an opening 412 having a smaller cross-sectional area
than an adjacent or contiguous cross-sectional area of interior
volume 406 of capillary tube 400. As may be seen in FIG. 4,
interior volume 406 of capillary tube 400 may have a generally
constant cross-sectional area between first and second end portions
402, 404 of capillary tube 400.
[0056] By providing fixed restriction orifice 410 with opening 412
at first end portion 402 of capillary tube 400, fixed restriction
orifice 410 can adjust the restriction on the flow of refrigerant
through capillary tube 400 depending upon a direction of the flow
of refrigerant through capillary tube 400, e.g., in the same or
similar manner to block 210 (FIG. 3) described above. For example,
because opening 412 of fixed restriction orifice 410 has a smaller
cross-sectional area than the cross-sectional area of interior
volume 406 of capillary tube 400 at first end portion 402 of
capillary tube 400, the restriction on the flow of refrigerant when
sealed system 120 is operating in the heating mode is greater than
when sealed system 120 is operating in the cooling mode.
[0057] Fixed restriction orifice 410 may be formed of or within any
suitable material. For example, fixed restriction orifice 410 may
be formed of a common material as capillary tube 400, such as
copper or aluminum. Fixed restriction orifice 410 may also be
mounted to capillary tube 400 and/or exterior coil 126 (FIG. 2). As
an example, fixed restriction orifice 410 may be brazed or
interference fit onto capillary tube 400 at first end portion 402
of capillary tube 400. As another example, fixed restriction
orifice 410 may be brazed or interference fit onto a jumper tube of
exterior coil 126.
[0058] FIG. 6 provides a perspective view of a capillary tube 500
according still another exemplary embodiment of the present subject
matter. Capillary tube 500 may be used in any suitable heat pump
system. For example, capillary tube 500 may be used in packaged
terminal air conditioner unit 100 as capillary tube 128 of sealed
system 120 (FIG. 2). As discussed in greater detail below,
capillary tube 500 includes features for adjusting a restriction on
a flow of refrigerant through capillary tube 500 depending upon a
direction of the flow of refrigerant through capillary tube
500.
[0059] Capillary tube 500 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 500 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 500 extends between a first end portion 502 and a
second end portion 504 and defines an interior volume (not shown)
for directing the flow of refrigerant through capillary tube
500.
[0060] Capillary tube 500 also includes a plurality of coils 510
defined by capillary tube 500 at or adjacent first end portion 502
of capillary tube 500. Coils 510 are formed by or with capillary
tube 500. The interior volume of capillary tube 500 may have a
generally constant cross-sectional area between first and second
end portions 502, 504 of capillary tube 500 including coils
510.
[0061] By changing the direction of refrigerant within capillary
tube 500, coils 510 can adjust the restriction on the flow of
refrigerant through capillary tube 500 depending upon a direction
of the flow of refrigerant through capillary tube 500, e.g., in the
same or similar manner to block 210 (FIG. 3) described above. For
example, due to the flow path for refrigerant provided by coils
510, the restriction on the flow of refrigerant when sealed system
120 is operating in the heating mode is greater than when sealed
system 120 is operating in the cooling mode.
[0062] Coils 510 may be formed in any suitable manner on capillary
tube 500. For example, a clamp or roller may plastically deform
capillary tube 500 in order to form coils 510 at first end portion
502 of capillary tube 500. Coils 510 may include any suitable
number of coils. For example, coils 510 may include at least two
coils, at least three coils, at least five coils, at least ten
coils, etc.
[0063] As may be seen in FIG. 4, capillary tube 500 defines a
length L between first and second end portions 502, 504 of
capillary tube 500. Coils 510 also define a length OL on capillary
tube 500. The length OL of coils 510 may be less than the length L
of capillary tube 500. For example, the length OL of coils 510 may
be no greater than a quarter of the length L of capillary tube 500.
As another example, the length OL of coils 510 may be no greater
than a tenth of the length L of capillary tube 500.
[0064] FIG. 7 provides a perspective view of a capillary tube 600
according yet another exemplary embodiment of the present subject
matter. FIGS. 8 and 9 provide partial section views capillary tube
600 and a flow washer 610 of capillary tube 600. Capillary tube 600
may be used in any suitable heat pump system. For example,
capillary tube 600 may be used in packaged terminal air conditioner
unit 100 as capillary tube 128 of sealed system 120 (FIG. 2). As
discussed in greater detail below, capillary tube 600 includes
features for adjusting a restriction on a flow of refrigerant
through capillary tube 600 depending upon a direction of the flow
of refrigerant through capillary tube 600.
[0065] Capillary tube 600 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 600 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 600 extends between a first end portion 602 and a
second end portion 604 and defines an interior volume 606 for
directing the flow of refrigerant through capillary tube 600.
[0066] Capillary tube 600 also includes a flow washer 610
positioned within interior volume 606 of capillary tube 600 at or
adjacent first end portion 602 of capillary tube 600. Flow washer
610 is deformable or moveable between various configurations that
adjust a size of an opening 612 of flow washer 610. For example, as
shown in FIG. 8, opening 612 of flow washer 610 has a first size
when refrigerant is flowing in a first direction through interior
volume 606 of capillary tube 600. As another example, as shown in
FIG. 9, opening 612 of flow washer 610 has a second size when
refrigerant is flowing in a second direction through interior
volume 606 of capillary tube 600. The first size is different than
the second size. For example, the first size may be larger than the
second size. Thus, the size of opening 612 of flow washer 610
changes depending upon the direction of refrigerant flow through
capillary tube 600. Flow washer 610 may elastically deform or
actuate in any other suitable manner in order to adjust the size of
opening 612 of flow washer 610 when the direction of refrigerant
flow through capillary tube 600 changes.
[0067] By changing the size of opening 612 of flow washer 610, flow
washer 610 can adjust the restriction on the flow of refrigerant
through capillary tube 600 depending upon a direction of the flow
of refrigerant through capillary tube 600, e.g., in the same or
similar manner to block 210 (FIG. 3) described above. For example,
by changing the size of opening 612 of flow washer 610, the
restriction on the flow of refrigerant when sealed system 120 is
operating in the heating mode is greater than when sealed system
120 is operating in the cooling mode. Flow washer 610 may be formed
of any suitable material. For example, flow washer 610 may be
formed with an elastically deformable material, such as rubber.
[0068] FIG. 10 provides a section view of a capillary tube 700
according yet another additional exemplary embodiment of the
present subject matter. Capillary tube 700 may be used in any
suitable heat pump system. For example, capillary tube 700 may be
used in packaged terminal air conditioner unit 100 as capillary
tube 128 of sealed system 120 (FIG. 2). As discussed in greater
detail below, capillary tube 700 includes features for adjusting a
restriction on a flow of refrigerant through capillary tube 700
depending upon a direction of the flow of refrigerant through
capillary tube 700.
[0069] Capillary tube 700 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 700 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 700 extends between a first end portion 702 and a
second end portion 704 and defines an interior volume 706 for
directing the flow of refrigerant through capillary tube 700.
[0070] Capillary tube 700 also includes a plurality of conical
segments 710 defined by an inner surface 708 at or adjacent first
end portion 702 of capillary tube 700. Conical segments 710 are
formed by capillary tube 700 such that each conical segment of
conical segments 710 successively reduces the cross-sectional area
of interior volume 706 of capillary tube 700 at conical segments
710. Thus, each conical segment of conical segments 3710 may expand
along an axial direction A defined between first and second end
portions 702, 704 of capillary tube 700. As may be seen in FIG. 4,
interior volume 706 of capillary tube 700 may have a generally
constant cross-sectional area between first and second end portions
702, 704 of capillary tube 700 except for conical segments 710.
[0071] By sequentially reducing the cross-sectional area of
interior volume 706 of capillary tube 700 at first end portion 702
of capillary tube 700, conical segments 710 can adjust the
restriction on the flow of refrigerant through capillary tube 700
depending upon a direction of the flow of refrigerant through
capillary tube 700, e.g., in the same or similar manner to block
210 (FIG. 3) described above. For example, by sequentially reducing
the cross-sectional area of interior volume 706 of capillary tube
700 at first end portion 702 of capillary tube 700, the restriction
on the flow of refrigerant when sealed system 120 is operating in
the heating mode is greater than when sealed system 120 is
operating in the cooling mode.
[0072] Conical segments 710 may include any suitable number of
conical segments. For example, conical segments 710 may include at
least two conical segments, at least three conical segments, at
least five conical segments, at least ten conical segments, etc. It
should be understood that segments 710 may have any other suitable
expanding cross-sectional shape in alternative exemplary
embodiments. For example, segments 710 may have a frustoconical
shape.
[0073] As may be seen in FIG. 10, capillary tube 700 defines a
length L between first and second end portions 702, 704 of
capillary tube 700. Conical segments 710 also define a length SL on
capillary tube 700. The length SL of conical segments 710 may be
less than the length L of capillary tube 700. For example, the
length SL of conical segments 710 may be no greater than a quarter
of the length L of capillary tube 700. As another example, the
length SL of conical segments 710 may be no greater than a tenth of
the length L of capillary tube 700.
[0074] FIGS. 11 and 12 provide schematic views of a capillary tube
800 according still yet another additional exemplary embodiment of
the present subject matter. Capillary tube 800 may be used in any
suitable heat pump system. For example, capillary tube 800 may be
used in packaged terminal air conditioner unit 100 as capillary
tube 128 of sealed system 120 (FIG. 2). As discussed in greater
detail below, capillary tube 800 includes features for adjusting a
restriction on a flow of refrigerant through capillary tube 800
depending upon a direction of the flow of refrigerant through
capillary tube 800.
[0075] Capillary tube 800 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 800 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 800 extends between a first end portion 802 and a
second end portion 804 and defines an interior volume 806 for
directing the flow of refrigerant through capillary tube 800.
[0076] Capillary tube 800 also includes a piston 810 slidably or
movably disposed within interior volume 806 of capillary tube 800
at first end portion 802 of capillary tube 800. In particular,
piston 810 is slidable within interior volume 806 between a first
position (FIG. 11) and a second position (FIG. 12). Piston 810
obstructs more refrigerant flow through interior volume 806 of
capillary tube 800 in the first position than in the second
position. For example, piston 810 may define a plurality of
channels 812 therein. When piston 810 is in the first position as
shown in FIG. 11, refrigerant may flow through all of channels 812.
Conversely, at least one of channels 812 is blocked or obstructed
when piston 810 is in the second position as shown in FIG. 12.
[0077] By moving between the first and second positions, piston 810
can adjust the restriction on the flow of refrigerant through
capillary tube 800 depending upon a direction of the flow of
refrigerant through capillary tube 800, e.g., in the same or
similar manner to block 210 (FIG. 3) described above. For example,
by moving between the first and second positions, the restriction
on the flow of refrigerant when sealed system 120 is operating in
the heating mode is greater than when sealed system 120 is
operating in the cooling mode.
[0078] FIG. 13 provides a perspective view of a capillary tube 900
according an additional exemplary embodiment of the present subject
matter. FIGS. 14 and 15 provide section views of capillary tube
900. Capillary tube 900 may be used in any suitable heat pump
system. For example, capillary tube 900 may be used in packaged
terminal air conditioner unit 100 as capillary tube 128 of sealed
system 120 (FIG. 2). As discussed in greater detail below,
capillary tube 900 includes features for adjusting a restriction on
a flow of refrigerant through capillary tube 900 depending upon a
direction of the flow of refrigerant through capillary tube
900.
[0079] Capillary tube 900 includes a generally tubular body, such
as a copper or aluminum pipe. Capillary tube 900 may be constructed
in the same or similar manner to capillary tube 200 (FIG. 4). Thus,
capillary tube 900 extends between a first end portion 902 and a
second end portion 904 and defines an interior volume 906 for
directing the flow of refrigerant through capillary tube 900.
[0080] As may be seen in FIGS. 14 and 15, interior volume 906 of
capillary tube 900 may have a varying or expanding cross-sectional
area between first and second end portions 902, 904 of capillary
tube 900. As shown in FIG. 15, capillary tube 900 may also define a
chamber 910 at or adjacent first end portion 902 of capillary tube
900. Thus, the cross-sectional area of interior volume 906 of
capillary tube 900 may uniformly vary or expand along a length L of
capillary tube 900.
[0081] By varying the cross-sectional area of interior volume 906
of capillary tube 900 between first and second end portions 902,
904 of capillary tube 900, conical segments 910 can adjust the
restriction on the flow of refrigerant through capillary tube 900
depending upon a direction of the flow of refrigerant through
capillary tube 900, e.g., in the same or similar manner to block
210 (FIG. 3) described above. For example, by varying the
cross-sectional area of interior volume 906 of capillary tube 900
between first and second end portions 902, 904 of capillary tube
900, the restriction on the flow of refrigerant when sealed system
120 is operating in the heating mode is greater than when sealed
system 120 is operating in the cooling mode.
[0082] FIGS. 16 and 17 provide section views of capillary tube 900
with another internal configuration for adjusting the restriction
on the flow of refrigerant through capillary tube 900 depending
upon a direction of the flow of refrigerant through capillary tube
900. As may be seen in FIGS. 16 and 7, capillary tube 900 may
define a plurality of channels 920 therein, e.g., that extend
between first and second end portions 902, 904 of capillary tube
900. A plug or bung 922 is movably disposed within chamber 910.
Bung 922 is rollable within interior volume 806 between a first
position (FIG. 16) and a second position (FIG. 17). Bung 922
obstructs at least one of passages 920 when bung 922 is in the
first position. Conversely, bung 922 not block any of passages 920
or block the one of passages to a less degree when bung 922 is in
the second position.
[0083] By moving between the first and second positions, bung 922
can adjust the restriction on the flow of refrigerant through
capillary tube 900 depending upon a direction of the flow of
refrigerant through capillary tube 900, e.g., in the same or
similar manner to block 210 (FIG. 3) described above. For example,
by moving between the first and second positions, the restriction
on the flow of refrigerant when sealed system 120 is operating in
the heating mode is greater than when sealed system 120 is
operating in the cooling mode.
[0084] Any suitable methods may be used to form capillary tube 900.
For example, capillary tube 900 may be fabricated as a unitary
capillary tube, e.g., such that capillary tube 900 is formed of a
single continuous piece of metal, plastic or other suitable
material. More particularly, capillary tube 900 may be manufactured
or formed using an additive process, such as Fused Deposition
Modeling (FDM), Selective Laser Sintering (SLS), Stereolithography
(SLA), Digital Light Processing (DLP) and other known processes. An
additive process fabricates metal or plastic components using
three-dimensional information, for example a three-dimensional
computer model, of the component. The three-dimensional information
is converted into a plurality of slices, each slice defining a
cross section of the component for a predetermined height of the
slice. The component is then "built-up" slice by slice, or layer by
layer, until finished.
[0085] Accordingly, three-dimensional information of capillary tube
900 may be determined. As an example, a model or prototype of
capillary tube 900 may be scanned to determine the
three-dimensional information of capillary tube 900. As another
example, a model of capillary tube 900 may be constructed using a
suitable CAD program to determine the three-dimensional information
of capillary tube 900. The three-dimensional information may then
be converted into a plurality of slices that each defines a
cross-sectional layer of capillary tube 900. As an example, the
three-dimensional information may be divided into equal sections or
segments, e.g., along a central axis of capillary tube 900 or any
other suitable axis. Thus, the three-dimensional information may be
discretized in order to provide planar cross-sectional layers of
capillary tube 900.
[0086] Capillary tube 900 may then be fabricated using the additive
process, or more specifically each layer is successively formed,
e.g., by fusing or polymerizing a metal or plastic using laser
energy or heat. The layers may have any suitable size. For example,
each layer may have a size between about five ten-thousandths of an
inch and about one thousandths of an inch. Capillary tube 900 may
be fabricated using any suitable additive manufacturing machine.
For example, any suitable laser sintering machine, inkjet printer
or laserjet printer may be used.
[0087] Utilizing additive manufacturing, capillary tube 900 may
have fewer components and/or joints than known capillary tubes.
Specifically, capillary tube 900 may require fewer components
because capillary tube 900 may be a single piece of continuous
metal or plastic, e.g., rather than multiple pieces of metal or
plastic joined or connected together. Also, the shape, contour and
features of capillary tube 900 described above may be formed using
such methods. As a result, capillary tube 900 may provide improved
efficiency for a heat pump system, such as sealed system 120, by
adjusting the restriction on the flow of refrigerant through
capillary tube 900 depending upon a direction of the flow of
refrigerant through capillary tube 900. Also, capillary tube 900
may be less prone to leaks and/or be stronger when formed with
additive processes. It should be understood that other capillary
tubes, such as capillary tube 200 (FIG. 3), capillary tube 300
(FIG. 4), capillary tube 400 (FIG. 5), capillary tube 500 (FIG. 6),
capillary tube 600 (FIG. 7), capillary tube 700 (FIG. 10) and/or
capillary tube 800 (FIG. 11), may also be manufactured or formed
using the addictive processes described above.
[0088] 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.
* * * * *