U.S. patent application number 15/237697 was filed with the patent office on 2018-02-22 for compressor with a discharge valve.
The applicant listed for this patent is Haier US Appliance Solutions, Inc.. Invention is credited to Gregory William Hahn.
Application Number | 20180051685 15/237697 |
Document ID | / |
Family ID | 61191407 |
Filed Date | 2018-02-22 |
United States Patent
Application |
20180051685 |
Kind Code |
A1 |
Hahn; Gregory William |
February 22, 2018 |
COMPRESSOR WITH A DISCHARGE VALVE
Abstract
A compressor includes a discharge valve with a first valve head
and a second valve head. The first valve head defines a passage
that extends through the first valve head along an axial direction.
A first spring is coupled to the first valve head. A second valve
head is positioned at the passage of the first valve head. A second
spring urges the second valve head towards the first valve
head.
Inventors: |
Hahn; Gregory William;
(Louisville, KY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Haier US Appliance Solutions, Inc. |
Wilmington |
DE |
US |
|
|
Family ID: |
61191407 |
Appl. No.: |
15/237697 |
Filed: |
August 16, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 39/1073 20130101;
F25B 2400/073 20130101; F04B 53/1032 20130101; F25B 2500/07
20130101; F04B 35/04 20130101; F04B 39/10 20130101; F25B 2500/06
20130101; F04B 39/08 20130101; F25B 1/02 20130101; F04B 35/045
20130101 |
International
Class: |
F04B 39/10 20060101
F04B039/10; F04B 39/08 20060101 F04B039/08; F04B 35/04 20060101
F04B035/04; F25B 1/02 20060101 F25B001/02; F25B 41/04 20060101
F25B041/04 |
Claims
1. A compressor, comprising: a casing defining a chamber; a piston
disposed within the chamber of the casing, the piston reciprocable
within the chamber of the casing along an axial direction; a
discharge valve comprising a housing; a first valve head positioned
adjacent the chamber of the casing, the first valve head having a
width along a radial direction that is perpendicular to the axial
direction, the first valve head also defining a passage that
extends through the first valve head along the axial direction; a
first spring coupled to the housing and the first valve head such
that the first spring urges the first valve head towards the
casing; a second valve head positioned at the passage of the first
valve head, the second valve head having a width along the radial
direction, the width of the second valve head being less than the
width of the first valve head; and a second spring coupled to the
second valve head such that the second spring urges the second
valve head towards the first valve head.
2. The compressor of claim 1, wherein the housing comprises an end
wall and a cylindrical side wall, the cylindrical side wall
extending from the end wall to the casing, the first spring
extending between the end wall of the housing and the first valve
head within the housing.
3. The compressor of claim 2, wherein the discharge valve further
comprises a post that is mounted to the end wall of the housing,
the second spring extending between the post and the second valve
head within the housing.
4. The compressor of claim 2, wherein the discharge valve further
comprises a retainer mounted to the first valve head, the second
spring extending between the retainer and the second valve head
within the housing.
5. The compressor of claim 1, wherein the first and second valve
heads have circular outer perimeters and the widths of the first
and second valve heads are diameters.
6. The compressor of claim 1, wherein the width of the first valve
head no less than twice the width of the second valve head.
7. The compressor of claim 1, wherein the first valve head is
seated on the casing when the first valve head is closed and the
second valve head is seated on the first valve head when the second
valve head is closed.
8. The compressor of claim 1, wherein the first and second springs
are coil springs.
9. The compressor of claim 1, wherein a stiffness of the first
spring is greater than a stiffness of the second spring.
10. The compressor of claim 1, wherein a mass of the first valve
head is greater than a mass of the second valve head.
11. A compressor, comprising: a casing defining a chamber; a piston
disposed within the chamber of the casing, the piston reciprocable
within the chamber of the casing along an axial direction; a
discharge valve comprising a housing; a first valve head positioned
adjacent the chamber of the casing, the first valve head having a
mass, the first valve head also defining a passage that extends
through the first valve head along the axial direction; a first
spring coupled to the housing and the first valve head such that
the first spring urges the first valve head towards the casing, the
first spring having a stiffness; a second valve head positioned at
the passage of the first valve head, the second valve head having a
mass, the mass of the second valve head being less than the mass of
the first valve head; and a second spring coupled to the second
valve head such that the second spring urges the second valve head
towards the first valve head, the second spring having a stiffness,
the stiffness of the second spring being less than the stiffness of
the first spring.
12. The compressor of claim 11, wherein the housing comprises an
end wall and a cylindrical side wall, the cylindrical side wall
extending from the end wall to the casing, the first spring
extending between the end wall of the housing and the first valve
head within the housing.
13. The compressor of claim 12, wherein the discharge valve further
comprises a post that is mounted to the end wall of the housing,
the second spring extending between the post and the second valve
head within the housing.
14. The compressor of claim 12, wherein the discharge valve further
comprises a retainer mounted to the first valve head, the second
spring extending between the retainer and the second valve head
within the housing.
15. The compressor of claim 1, wherein the first valve head is
seated on the casing when the first valve head is closed and the
second valve head is seated on the first valve head when the second
valve head is closed.
16. The compressor of claim 1, wherein a mass of the first valve
head is greater than a mass of the second valve head.
17. A compressor, comprising: a casing defining a chamber; a piston
disposed within the chamber of the casing, the piston reciprocable
within the chamber of the casing along an axial direction; a
discharge valve comprising a housing; a valve head positioned
adjacent the chamber of the casing, the valve head defining a
passage that extends through the valve head along the axial
direction; a spring coupled to the housing and the valve head such
that the spring urges the valve head towards the casing; a reed
positioned at the passage of the valve head, the reed mounted to
the valve head such that the reed is cantilevered over the passage
of the valve head.
18. The compressor of claim 17, wherein the valve head is seated on
the casing when the valve head is closed and the reed is seated on
the valve head when the reed is closed.
19. The compressor of claim 18, wherein the discharge valve further
comprises a valve stop and a shaft mounted to the valve head, the
reed positioned against the valve stop when the reed is open, the
shaft extending across an annular side wall of the valve head, the
valve stop positioned between the reed and the shaft.
20. The compressor of claim 18, wherein the discharge valve further
comprises a damper reed mounted to the valve head and positioned on
the reed, the damper reed opposing movement of the reed away from
the passage of the valve head.
Description
FIELD OF THE INVENTION
[0001] The present subject matter relates generally to compressors
and discharge valves for compressors.
BACKGROUND OF THE INVENTION
[0002] Certain refrigerator appliances include sealed systems for
cooling chilled chambers of the refrigerator appliance. The sealed
systems generally include a compressor that generates compressed
refrigerant during operation of the sealed system. The compressed
refrigerant flows to an evaporator where heat exchange between the
chilled chambers and the refrigerant cools the chilled chambers and
food items located therein.
[0003] Recently, certain refrigerator appliances have included
linear compressors for compressing refrigerant. Linear compressors
generally include a piston and a driving coil. The driving coil
receives a current that generates a force for sliding the piston
forward and backward within a chamber. During motion of the piston
within the chamber, the piston compresses refrigerant. A discharge
valve regulates a flow of pressured refrigerant from the
chamber.
[0004] Over-pressurization of the chamber can negatively affect
performance of the linear compressor, and the discharge valve
design frequently exacerbates the over-pressurization. In
particular, a mass of the discharge valve can require a cylinder
pressure to exceed a discharge muffler pressure by a certain margin
before the discharge valve opens. A high mass discharge valve
responds slowly and increases the amount of work required to open
the discharge valve. However, high mass is generally required to
provide a discharge valve that covers the chamber at an end of the
cylinder and thereby allow the piston to run and "crash" into the
discharge valve without damaging the linear compressor. Thus, a
full cylinder diameter discharge valve is disadvantageously massive
but has other benefits.
[0005] Accordingly, a linear compressor with a discharge valve
having features limits over-pressurization of a chamber while also
permitting crashing of a piston would be useful.
BRIEF DESCRIPTION OF THE INVENTION
[0006] The present subject matter provides a compressor. The
compressor includes a discharge valve with a first valve head and a
second valve head. The first valve head defines a passage that
extends through the first valve head along an axial direction. A
first spring urges the first valve head towards a casing. A second
valve head is positioned at the passage of the first valve head. A
second spring urges the second valve head towards the first valve
head. 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.
[0007] In a first exemplary embodiment, a compressor is provided.
The compressor includes a casing that defines a chamber. A piston
is disposed within the chamber of the casing. The piston is
reciprocable within the chamber of the casing along an axial
direction. A discharge valve includes a housing. A first valve head
is positioned adjacent the chamber of the casing. The first valve
head has a width along a radial direction that is perpendicular to
the axial direction. The first valve head also defines a passage
that extends through the first valve head along the axial
direction. A first spring is coupled to the housing and the first
valve head such that the first spring urges the first valve head
towards the casing. A second valve head is positioned at the
passage of the first valve head. The second valve head has a width
along the radial direction. The width of the second valve head is
less than the width of the first valve head. A second spring is
coupled to the second valve head such that the second spring urges
the second valve head towards the first valve head.
[0008] In a second exemplary embodiment, a compressor is provided.
The compressor includes a casing that defines a chamber. A piston
is disposed within the chamber of the casing. The piston is
reciprocable within the chamber of the casing along an axial
direction. A discharge valve includes a housing. A first valve head
is positioned adjacent the chamber of the casing. The first valve
head has a mass. The first valve head also defines a passage that
extends through the first valve head along the axial direction. A
first spring is coupled to the housing and the first valve head
such that the first spring urges the first valve head towards the
casing. The first spring has a stiffness. A second valve head is
positioned at the passage of the first valve head. The second valve
head has a mass. The mass of the second valve head is less than the
mass of the first valve head. A second spring is coupled to the
second valve head such that the second spring urges the second
valve head towards the first valve head. The second spring has a
stiffness. The stiffness of the second spring is less than the
stiffness of the first spring.
[0009] In a third exemplary embodiment, a compressor is provided.
The compressor includes a casing that defines a chamber. A piston
is disposed within the chamber of the casing. The piston is
reciprocable within the chamber of the casing along an axial
direction. A discharge valve includes a housing. A valve head is
positioned adjacent the chamber of the casing. The valve head
defines a passage that extends through the valve head along the
axial direction. A spring is coupled to the housing and the valve
head such that the spring urges the valve head towards the casing.
A reed is positioned at the passage of the valve head. The reed is
mounted to the valve head such that the reed is cantilevered over
the passage of the valve head.
[0010] 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
[0011] 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.
[0012] FIG. 1 is a front elevation view of a refrigerator appliance
according to an exemplary embodiment of the present subject
matter.
[0013] FIG. 2 is schematic view of certain components of the
exemplary refrigerator appliance of FIG. 1.
[0014] FIG. 3 provides a section view of a linear compressor
according to an exemplary embodiment of the present subject
matter.
[0015] FIG. 4 provides a partial, section view of a discharge valve
on a linear compressor according to an exemplary embodiment of the
present subject matter.
[0016] FIG. 5 provides a section view of a discharge valve
according to an exemplary embodiment of the present subject
matter.
[0017] FIG. 6 provides a section view of a discharge valve
according to another exemplary embodiment of the present subject
matter.
[0018] FIG. 7 provides a perspective view of components of a
discharge valve according to an additional exemplary embodiment of
the present subject matter.
[0019] FIG. 8 provides a section view of the components of the
discharge valve of FIG. 7.
[0020] FIG. 8 provides an exploded view of the components of the
discharge valve of FIG. 7.
DETAILED DESCRIPTION
[0021] 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.
[0022] FIG. 1 depicts a refrigerator appliance 10 that incorporates
a sealed refrigeration system 60 (FIG. 2). It should be appreciated
that the term "refrigerator appliance" is used in a generic sense
herein to encompass any manner of refrigeration appliance, such as
a freezer, refrigerator/freezer combination, and any style or model
of conventional refrigerator. In addition, it should be understood
that the present subject matter is not limited to use in
appliances. Thus, the present subject matter may be used for any
other suitable purpose, such as vapor compression within air
conditioning units or air compression within air compressors.
[0023] In the illustrated exemplary embodiment shown in FIG. 1, the
refrigerator appliance 10 is depicted as an upright refrigerator
having a cabinet or casing 12 that defines a number of internal
chilled storage compartments. In particular, refrigerator appliance
10 includes upper fresh-food compartments 14 having doors 16 and
lower freezer compartment 18 having upper drawer 20 and lower
drawer 22. The drawers 20 and 22 are "pull-out" drawers in that
they can be manually moved into and out of the freezer compartment
18 on suitable slide mechanisms.
[0024] FIG. 2 is a schematic view of certain components of
refrigerator appliance 10, including a sealed refrigeration system
60 of refrigerator appliance 10. A machinery compartment 62
contains components for executing a known vapor compression cycle
for cooling air. The components include a compressor 64, a
condenser 66, an expansion device 68, and an evaporator 70
connected in series and charged with a refrigerant. As will be
understood by those skilled in the art, refrigeration system 60 may
include additional components, e.g., at least one additional
evaporator, compressor, expansion device, and/or condenser. As an
example, refrigeration system 60 may include two evaporators.
[0025] Within refrigeration system 60, refrigerant flows into
compressor 64, which operates to increase the pressure of the
refrigerant. This compression of the refrigerant raises its
temperature, which is lowered by passing the refrigerant through
condenser 66. Within condenser 66, heat exchange with ambient air
takes place so as to cool the refrigerant. A fan 72 is used to pull
air across condenser 66, as illustrated by arrows A.sub.C, so as to
provide forced convection for a more rapid and efficient heat
exchange between the refrigerant within condenser 66 and the
ambient air. Thus, as will be understood by those skilled in the
art, increasing air flow across condenser 66 can, e.g., increase
the efficiency of condenser 66 by improving cooling of the
refrigerant contained therein.
[0026] An expansion device (e.g., a valve, capillary tube, or other
restriction device) 68 receives refrigerant from condenser 66. From
expansion device 68, the refrigerant enters evaporator 70. Upon
exiting expansion device 68 and entering evaporator 70, the
refrigerant drops in pressure. Due to the pressure drop and/or
phase change of the refrigerant, evaporator 70 is cool relative to
compartments 14 and 18 of refrigerator appliance 10. As such,
cooled air is produced and refrigerates compartments 14 and 18 of
refrigerator appliance 10. Thus, evaporator 70 is a type of heat
exchanger which transfers heat from air passing over evaporator 70
to refrigerant flowing through evaporator 70.
[0027] Collectively, the vapor compression cycle components in a
refrigeration circuit, associated fans, and associated compartments
are sometimes referred to as a sealed refrigeration system operable
to force cold air through compartments 14, 18 (FIG. 1). The
refrigeration system 60 depicted in FIG. 2 is provided by way of
example only. Thus, it is within the scope of the present subject
matter for other configurations of the refrigeration system to be
used as well.
[0028] FIG. 3 provides a section view of a linear compressor 100
according to an exemplary embodiment of the present subject matter.
As discussed in greater detail below, linear compressor 100 is
operable to increase a pressure of fluid within a chamber 112 of
linear compressor 100. Linear compressor 100 may be used to
compress any suitable fluid, such as refrigerant or air. In
particular, linear compressor 100 may be used in a refrigerator
appliance, such as refrigerator appliance 10 (FIG. 1) in which
linear compressor 100 may be used as compressor 64 (FIG. 2). As may
be seen in FIG. 3, linear compressor 100 defines an axial direction
A, a radial direction R and a circumferential direction C. Linear
compressor 100 may be enclosed within a hermetic or air-tight shell
(not shown). The hermetic shell can, e.g., hinder or prevent
refrigerant from leaking or escaping from refrigeration system
60.
[0029] Turning now to FIG. 3, linear compressor 100 includes a
casing 110 that extends between a first end portion 102 and a
second end portion 104, e.g., along the axial direction A. Casing
110 includes various static or non-moving structural components of
linear compressor 100. In particular, casing 110 includes a
cylinder assembly 111 that defines a chamber 112. Cylinder assembly
111 is positioned at or adjacent second end portion 104 of casing
110. Chamber 112 extends longitudinally along the axial direction
A. Casing 110 also includes a motor mount mid-section 113 and an
end cap 115 positioned opposite each other about a motor. A stator,
e.g., including an outer back iron 150 and a driving coil 152, of
the motor is mounted or secured to casing 110, e.g., such that the
stator is sandwiched between motor mount mid-section 113 and end
cap 115 of casing 110. Linear compressor 100 also includes valves
(such as a discharge valve assembly 117 at an end of chamber 112)
that permit refrigerant to enter and exit chamber 112 during
operation of linear compressor 100.
[0030] A piston assembly 114 with a piston head 116 is slidably
received within chamber 112 of cylinder assembly 111. In
particular, piston assembly 114 is slidable along the axial
direction A. During sliding of piston head 116 within chamber 112,
piston head 116 compresses refrigerant within chamber 112. As an
example, from a top dead center position, piston head 116 can slide
within chamber 112 towards a bottom dead center position along the
axial direction A, i.e., an expansion stroke of piston head 116.
When piston head 116 reaches the bottom dead center position,
piston head 116 changes directions and slides in chamber 112 back
towards the top dead center position, i.e., a compression stroke of
piston head 116. It should be understood that linear compressor 100
may include an additional piston head and/or additional chamber at
an opposite end of linear compressor 100. Thus, linear compressor
100 may have multiple piston heads in alternative exemplary
embodiments.
[0031] As may be seen in FIG. 3, linear compressor 100 also
includes an inner back iron assembly 130. Inner back iron assembly
130 is positioned in the stator of the motor. In particular, outer
back iron 150 and/or driving coil 152 may extend about inner back
iron assembly 130, e.g., along the circumferential direction C.
Inner back iron assembly 130 also has an outer surface 137. At
least one driving magnet 140 is mounted to inner back iron assembly
130, e.g., at outer surface 137 of inner back iron assembly 130.
Driving magnet 140 may face and/or be exposed to driving coil 152.
In particular, driving magnet 140 may be spaced apart from driving
coil 152, e.g., along the radial direction R by an air gap. Thus,
the air gap may be defined between opposing surfaces of driving
magnet 140 and driving coil 152. Driving magnet 140 may also be
mounted or fixed to inner back iron assembly 130 such that an outer
surface of driving magnet 140 is substantially flush with outer
surface 137 of inner back iron assembly 130. Thus, driving magnet
140 may be inset within inner back iron assembly 130. In such a
manner, the magnetic field from driving coil 152 may have to pass
through only a single air gap between outer back iron 150 and inner
back iron assembly 130 during operation of linear compressor 100,
and linear compressor 100 may be more efficient relative to linear
compressors with air gaps on both sides of a driving magnet.
[0032] As may be seen in FIG. 3, driving coil 152 extends about
inner back iron assembly 130, e.g., along the circumferential
direction C. Driving coil 152 is operable to move the inner back
iron assembly 130 along the axial direction A during operation of
driving coil 152. As an example, a current may be induced within
driving coil 152 by a current source (not shown) to generate a
magnetic field that engages driving magnet 140 and urges piston
assembly 114 to move along the axial direction A in order to
compress refrigerant within chamber 112 as described above and will
be understood by those skilled in the art. In particular, the
magnetic field of driving coil 152 may engage driving magnet 140 in
order to move inner back iron assembly 130 and piston head 116
along the axial direction A during operation of driving coil 152.
Thus, driving coil 152 may slide piston assembly 114 between the
top dead center position and the bottom dead center position, e.g.,
by moving inner back iron assembly 130 along the axial direction A,
during operation of driving coil 152.
[0033] Linear compressor 100 may include various components for
permitting and/or regulating operation of linear compressor 100. In
particular, linear compressor 100 includes a controller (not shown)
that is configured for regulating operation of linear compressor
100. The controller is in, e.g., operative, communication with the
motor, e.g., driving coil 152 of the motor. Thus, the controller
may selectively activate driving coil 152, e.g., by inducing
current in driving coil 152, in order to compress refrigerant with
piston assembly 114 as described above.
[0034] The controller 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
linear compressor 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, the
controller 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.
[0035] Linear compressor 100 also includes a spring 120. Spring 120
is positioned in inner back iron assembly 130. In particular, inner
back iron assembly 130 may extend about spring 120, e.g., along the
circumferential direction C. Spring 120 also extends between first
and second end portions 102 and 104 of casing 110, e.g., along the
axial direction A. Spring 120 assists with coupling inner back iron
assembly 130 to casing 110, e.g., cylinder assembly 111 of casing
110. In particular, inner back iron assembly 130 is fixed to spring
120 at a middle portion of spring 120 as discussed in greater
detail below.
[0036] During operation of driving coil 152, spring 120 supports
inner back iron assembly 130. In particular, inner back iron
assembly 130 is suspended by spring 120 within the stator or the
motor of linear compressor 100 such that motion of inner back iron
assembly 130 along the radial direction R is hindered or limited
while motion along the axial direction A is relatively unimpeded.
Thus, spring 120 may be substantially stiffer along the radial
direction R than along the axial direction A. In such a manner,
spring 120 can assist with maintaining a uniformity of the air gap
between driving magnet 140 and driving coil 152, e.g., along the
radial direction R, during operation of the motor and movement of
inner back iron assembly 130 on the axial direction A. Spring 120
can also assist with hindering side pull forces of the motor from
transmitting to piston assembly 114 and being reacted in cylinder
assembly 111 as a friction loss.
[0037] Inner back iron assembly 130 includes an outer cylinder 136
and a sleeve 139. Outer cylinder 136 defines outer surface 137 of
inner back iron assembly 130 and also has an inner surface 138
positioned opposite outer surface 137 of outer cylinder 136. Sleeve
139 is positioned on or at inner surface 138 of outer cylinder 136.
A first interference fit between outer cylinder 136 and sleeve 139
may couple or secure outer cylinder 136 and sleeve 139 together. In
alternative exemplary embodiments, sleeve 139 may be welded, glued,
fastened, or connected via any other suitable mechanism or method
to outer cylinder 136.
[0038] Sleeve 139 extends about spring 120, e.g., along the
circumferential direction C. In addition, a middle portion of
spring 120 is mounted or fixed to inner back iron assembly 130 with
sleeve 139. Sleeve 139 extends between inner surface 138 of outer
cylinder 136 and the middle portion of spring 120, e.g., along the
radial direction R. A second interference fit between sleeve 139
and the middle portion of spring 120 may couple or secure sleeve
139 and the middle portion of spring 120 together. In alternative
exemplary embodiments, sleeve 139 may be welded, glued, fastened,
or connected via any other suitable mechanism or method to the
middle portion of spring 120.
[0039] Outer cylinder 136 may be constructed of or with any
suitable material. For example, outer cylinder 136 may be
constructed of or with a plurality of (e.g., ferromagnetic)
laminations. The laminations are distributed along the
circumferential direction C in order to form outer cylinder 136 and
are mounted to one another or secured together, e.g., with rings
pressed onto ends of the laminations. Outer cylinder 136 defines a
recess that extends inwardly from outer surface 137 of outer
cylinder 136, e.g., along the radial direction R. Driving magnet
140 is positioned in the recess on outer cylinder 136, e.g., such
that driving magnet 140 is inset within outer cylinder 136.
[0040] A piston flex mount 160 is mounted to and extends through
inner back iron assembly 130. In particular, piston flex mount 160
is mounted to inner back iron assembly 130 via sleeve 139 and
spring 120. Thus, piston flex mount 160 may be coupled (e.g.,
threaded) to spring 120 at the middle portion of spring 120 in
order to mount or fix piston flex mount 160 to inner back iron
assembly 130. A coupling 170 extends between piston flex mount 160
and piston assembly 114, e.g., along the axial direction A. Thus,
coupling 170 connects inner back iron assembly 130 and piston
assembly 114 such that motion of inner back iron assembly 130,
e.g., along the axial direction A, is transferred to piston
assembly 114. Coupling 170 may extend through driving coil 152,
e.g., along the axial direction A.
[0041] Coupling 170 may be a compliant coupling that is compliant
or flexible along the radial direction R. In particular, coupling
170 may be sufficiently compliant along the radial direction R such
that little or no motion of inner back iron assembly 130 along the
radial direction R is transferred to piston assembly 114 by
coupling 170. In such a manner, side pull forces of the motor are
decoupled from piston assembly 114 and/or cylinder assembly 111 and
friction between piston assembly 114 and cylinder assembly 111 may
be reduced.
[0042] Piston flex mount 160 defines at least one suction gas inlet
162. Suction gas inlet 162 of piston flex mount 160 extends, e.g.,
along the axial direction A, through piston flex mount 160. Thus, a
flow of fluid, such as air or refrigerant, may pass through piston
flex mount 160 via suction gas inlet 162 of piston flex mount 160
during operation of linear compressor 100.
[0043] Piston head 116 also defines at least one opening 118.
Opening 118 of piston head 116 extends, e.g., along the axial
direction A, through piston head 116. Thus, the flow of fluid may
pass through piston head 116 via opening 118 of piston head 116
into chamber 112 during operation of linear compressor 100. In such
a manner, the flow of fluid (that is compressed by piston head 116
within chamber 112) may flow through piston flex mount 160 and
inner back iron assembly 130 to piston assembly 114 during
operation of linear compressor 100.
[0044] FIG. 4 provides a partial, section view of a discharge valve
200 according to an exemplary embodiment of the present subject
matter. Discharge valve 200 is described in greater detail below in
the context of linear compressor 100. Thus, discharge valve 200 may
be used as discharge valve assembly 117. However, it should be
understood that discharge valve 200 may be used in or with any
suitable compressor in alternative exemplary embodiments, e.g., to
regulate pressurized fluid flow from a chamber. As discussed in
greater detail below, discharge valve 200 includes features for
limiting over-pressurization of chamber 112 and thereby increasing
an efficiency of linear compressor 100, e.g., by requiring less
work to open discharge valve 200 relative to other discharge
valves. As may be seen in FIG. 4, discharge valve 200 includes a
housing 210, a first valve head 220, a first spring 230, a second
valve head 240 and a second spring 250.
[0045] Housing 210 may include an end wall 212 and a cylindrical
side wall 214. Cylindrical side wall 214 is mounted to end wall
212, and cylindrical side wall 214 extends from end wall 212, e.g.,
along the axial direction A, to cylinder assembly 111 of casing
110. Housing 210 may be mounted or fixed to casing 110, and other
components of discharge valve 200 may be disposed within housing
210. For example, a plate 218 of housing 210 at a distal end of
cylindrical side wall 214 may be positioned at or on cylinder
assembly 111, and a seal 219 may extend between cylinder assembly
111 and plate 218 of housing 210, e.g., along the axial direction
A, in order to limit fluid leakage at an axial gap between casing
110 and housing 210. Fasteners (not shown) may extend through plate
218 into casing 110 to mount housing 210 to casing 110. First valve
head 220, first spring 230, second valve head 240 and/or second
spring 250 may be disposed within housing 210 when housing 210 is
mounted to casing 110.
[0046] First valve head 220 is positioned at or adjacent chamber
112 of cylinder assembly 111. First valve head 220 defines a
passage 222 that extends through first valve head 220, e.g., along
the axial direction A. Passage 222 may be contiguous with chamber
112. First spring 230 is coupled to housing 210 and first valve
head 220, and first spring 230 is configured to urge first valve
head 220 towards or against cylinder assembly 111, e.g., along the
axial direction A. As shown in FIG. 4, one end of first spring 230
may be mounted to end wall 212 of housing 210 at a bracket 216 of
end wall 212, and another end of first spring 230 may be mounted to
an outer diameter of a support 224 of first valve head 220. Thus,
first spring 230 may be compressed between end wall 212 (e.g.,
bracket 216 of end wall 212) and first valve head 220 within
housing 210. First spring 230 may be a coil or helical spring in
certain exemplary embodiments.
[0047] Second valve head 240 is positioned at passage 222 of first
valve head 220, e.g., on first valve head 220. Second spring 250 is
coupled to second valve head 240, and second spring 250 is
configured for urging second valve head 240 towards or against
first valve head 220. As shown in FIG. 4, discharge valve 200 may
include a retainer 260 with a post 262. Retainer 260 is mounted to
first valve head 220. For example, retainer 260 may be snap-fit,
press-fit, ultra-sonically welded, fastened, adhered or otherwise
suitable mounted to support 224 of first valve head 220 at an inner
diameter of support 224. Post 262 is positioned at a central
portion of retainer 260 and extends, e.g., along the axial
direction A, towards second valve head 240. Second spring 250 may
be compressed between post 262 and second valve head 240. Second
spring 250 may be a coil or helical spring in certain exemplary
embodiments.
[0048] First valve head 220 and second valve head 240 are each
adjustable between an open position (not shown) and a closed
position (FIG. 4). Thus, first valve head 220 and second valve head
240 may be moveable, e.g., along the axial direction A, relative to
casing 110. In particular, during operation of linear compressor,
piston assembly 114 reciprocates within chamber 112 and pressurizes
fluid, and first and second valve heads 220, 240 shift between the
open and closed positions. For example, first and second springs
230, 250 bias first and second valve heads 220, 240 towards the
closed position, respectively. Thus, first and second valve heads
220, 240 are normally closed. When first valve head 220 is in the
closed position, first valve head 220 may be seated against
cylinder assembly 111 and thus assist with sealing chamber 112.
Similarly, second valve head 240 may be seated against first valve
head 220, e.g., opposite chamber 112, when second valve head 240 is
in the closed position. Thus, when first and second valve heads
220, 240 are both closed, discharge valve 200 may seal chamber 112
and thereby assist with pressurization of fluid due to motion of
piston assembly 114 within chamber 112.
[0049] When the fluid in chamber 112 reaches a first threshold
pressure, second valve head 240 may open. For example, fluid within
chamber 112 may apply a force onto second valve head 240 that
overcomes the force applied to second valve head 240 by second
spring 250 such that second valve head 240 moves, e.g., along the
axial direction A, away from first valve head 220 to the open
position. When second valve head 240 is in the open position, fluid
from chamber 112 may flow through passage 222 out of chamber 112
and into housing 210.
[0050] First valve head 220 may open when the fluid in chamber 112
reaches a second threshold pressure, e.g., that is greater than the
first threshold pressure. For example, fluid within chamber 112 may
apply a force onto first valve head 220 that overcomes the force
applied to first valve head 220 by first spring 230 such that first
valve head 220 moves, e.g., along the axial direction A, away from
cylinder assembly 111 to the open position. When first valve head
220 is in the open position, fluid from chamber 112 may flow
through out of chamber 112 through an axial gap between first valve
head 220 and cylinder assembly 111 into housing 210.
[0051] First valve head 220 may also move from the closed position
to the open position when piston assembly 114 strikes or impacts
first valve head 220. Thus, second valve head 240 may correspond to
a flow path for pressurized fluid from chamber 112 during normal
operation of linear compressor 100, and first valve head 220 may
correspond to a movable end wall of cylinder assembly 111 that
seals chamber 112 during normal operation of linear compressor 100
but is movable, e.g., along the axial direction A, to limit damage
to piston assembly 114 when piston assembly 114 strikes or impacts
first valve head 220.
[0052] As may be seen from the above, discharge valve 200 may have
a valve-on-valve design that includes at least two mechanisms for
releasing pressurized fluid from chamber 112. In particular, second
valve head 240 may be piggybacked onto first valve head 220. First
valve head 220 may be larger and less responsive while second valve
head 240 is smaller and more responsive. For example, second valve
head 240 may react and open under normal operating conditions and
thereby improve compressor efficiency relative to utilizing only
first valve head 220.
[0053] Various parameters of first valve head 220 and second valve
head 240 may be varied to allow second valve head 240 to be smaller
and more responsive relative to first valve head 220. For example,
a mass of first valve head 220 may be greater than a mass of second
valve head 240. As a particular example, the mass of first valve
head 220 may be no less than twice the mass of second valve head
240. First valve head 220 may also have a width W1, e.g., along the
radial direction R, and second valve head 240 may have a width W2,
e.g., along the radial direction R. The width W2 of second valve
head 240 may be less than the width W1 of first valve head 220. As
a particular example, the width W1 of first valve head 220 may be
no less than twice the width W2 of second valve head 240. First and
second valve heads 220, 240 may have circular outer perimeters, and
the widths W1, W2 of first and second valve heads 220, 240 may be
diameters. Parameters of first spring 230 and second spring 250 may
also be varied to allow second valve head 240 to be more responsive
relative to first valve head 220. For example, a stiffness of first
spring 230 may be greater than a stiffness of second spring 250. As
a particular example, the stiffness of first spring 230 may be no
less than twice the stiffness of second spring 250. Such relative
sizing of first and second valve heads 220, 240 and/or first and
second springs 230, 250 assists with providing the efficiency
increase in linear compressor 100 noted above.
[0054] As may be seen in FIG. 4, first spring 230 may assist with
seating first valve head 220 on casing 110 at chamber 112. In
particular, first valve head 220 may extend radially over chamber
112. Thus, the width W1 of first valve head 220 may be greater than
a width of chamber 112, e.g., along the radial direction R. Such
sizing of first valve head 220 relative to chamber 112 provides
that first valve head 220 may be wider than piston assembly 114,
e.g., along the radial direction R. Thus, first valve head 220 may
be sized to seal chamber 112 while also allowing crashing of piston
assembly 114 against first valve head 220 rather than other fixed
components of cylinder assembly 111.
[0055] Second spring 250 may assist with seating second valve head
240 on first valve head 220 at passage 222. In particular, second
valve head 240 may extend radially over passage 222. Thus, the
width W2 of second valve head 240 may be greater than a width of
passage 222, e.g., along the radial direction R.
[0056] FIG. 5 provides a section view of a discharge valve 300
according to an exemplary embodiment of the present subject matter.
Discharge valve 300 is constructed in a similar manner to discharge
valve 200 (FIG. 4) and includes numerous common components, as
shown with common reference numerals. However, first and second
springs 230, 250 are mounted in a different manner in discharge
valve 300.
[0057] As shown in FIG. 5, first spring 230 is coupled to housing
210 and first valve head 220. In particular, one end of first
spring 230 may be mounted to end wall 212 of housing 210 at a
bracket 216 of end wall 212, and another end of first spring 230
may be received within a retainer 310 mounted on first valve head
220. Thus, first spring 230 may extend between end wall 212 (e.g.,
bracket 216 of end wall 212) and retainer 310 within housing 210.
Retainer 310 may be snap-fit, press-fit, ultra-sonically welded,
fastened, adhered or otherwise suitable mounted to support 224 of
first valve head 220 at an outer diameter of support 224. Retainer
310 includes a post 312. Post 312 is positioned at a central
portion of retainer 310 and extends, e.g., along the axial
direction A, towards second valve head 240. Second spring 250 may
extend between post 312 and second valve head 240.
[0058] FIG. 6 provides a section view of a discharge valve 400
according to another exemplary embodiment of the present subject
matter. Discharge valve 400 is constructed in a similar manner to
discharge valve 200 (FIG. 4) and includes numerous common
components, as shown with common reference numerals. However,
second spring 250 is mounted in a different manner in discharge
valve 400.
[0059] As shown in FIG. 6, discharge valve 400 includes a post 410.
Post 410 is mounted to end wall 212 of housing 210. For example,
post 410 may be mounted to or formed with bracket 216 of end wall
212. Post 410 extends, e.g., along the axial direction A, from end
wall 212 towards second valve head 240. Second spring 250 extends
between post 410 and second valve head 240 within housing 210.
[0060] FIG. 7 provides a perspective view of components of a
discharge valve 500 according to an additional exemplary embodiment
of the present subject matter. FIG. 8 provides a second view of the
components of discharge valve 500. FIG. 9 provides an exploded view
of the components of discharge valve 500. Discharge valve 500 may
be used in or with any suitable compressor, such as linear
compressor 100. As an example, the components of discharge valve
500 may be used with linear compressor 100 in a similar manner to
that shown in FIG. 4 for discharge valve 200.
[0061] As may be seen in FIG. 7, discharge valve 500 includes a
valve head 510. Valve head 510 may be used and positioned in the
same or similar manner to that shown in FIG. 4 for first valve head
220. Thus, valve head 510 may be coupled to first spring 230 and
positioned at or adjacent chamber 112. Valve head 510 defines a
passage 512 that extends through valve head 510, e.g., along the
axial direction A.
[0062] A reed 520 is positioned at passage 512 of valve head 510.
Reed 520 may be mounted to valve head 510 such that reed 520 is
cantilevered over passage 512 of valve head 510. Reed 520 may
adjust between an open position (not shown) and a closed position
(FIG. 8). A distal end of reed 520 is seated on valve head 510 when
reed 520 is closed. Conversely, the distal end of reed 520 is
spaced apart from valve head 510 when reed 520 is open. Thus, reed
520 limits or blocks fluid flow through passage 512 when reed 520
is in the closed position while reed 520 permits fluid flow through
passage 512 when reed 520 is in the open position.
[0063] A reed damper or additional reed 525 may be disposed on or
over reed valve 520. Thus, reed valve 520 may be positioned between
passage 512 and additional reed 525. Additional reed 525 may be
stiffer than reed valve 520, e.g., along the axial direction A, in
certain exemplary embodiments. Additional reed 525 may dampen
opening or deformation of reed 520. For example, additional reed
525 may limit or prevent reed 520 from impacting a valve stop 528
as reed 520 shifts open. Valve stop 528 restricts movement of reed
520 and additional reed 525 during the discharge process, e.g.,
thereby preventing excess stress in reed 520 and additional reed
525. Thus, valve stop 528 may limit displacement or deformation of
reed 520 and/or additional reed 525, e.g., along the axial
direction A, away from passage 512. As an example, the distal end
of reed 520 and/or additional reed 525 may be positioned against
valve stop 528 when reed 520 is open, and the distal end of reed
520 and/or additional reed 525 may be spaced apart from valve stop
528 when reed 520 is closed. Discharge valve 500 may also include a
shaft 530 mounted to valve head 510, e.g., above reed 520. Shaft
530 may assist with mounting reed 520, additional reed 525 and/or
valve stop 528 to valve head 510.
[0064] In a similar manner to that described above for discharge
valve 200, discharge valve 500 may have a valve-on-valve design
that includes at least two mechanisms for releasing pressurized
fluid from chamber 112. In particular, reed 520 may be piggybacked
onto valve head 510. Valve head 510 may be larger and less
responsive while reed 520 is smaller and more responsive. For
example, reed 520 may react and open under normal operating
conditions and thereby improve compressor efficiency relative to
utilizing only valve head 510. Thus, e.g., a mass of reed 520 may
be less than a mass of valve head 510.
[0065] Discharge valve 200 (FIG. 4), discharge valve 300 (FIG. 5),
discharge valve 400 (FIG. 6) and discharge valve 500 (FIG. 7) may
be used in or with any suitable compressor. For example, discharge
valve 200, discharge valve 300, discharge valve 400 and discharge
valve 500 may be used in or with linear compressor 100, as
discharge valve assembly 117. As another example, discharge valve
200, discharge valve 300, discharge valve 400 and discharge valve
500 may be used in or with the linear compressor described in U.S.
Patent Publication No. 2015/0226197 of Gregory William Hahn et al.,
which is hereby incorporated by reference in its entirety for all
purposes. Thus, e.g., discharge valve 200, discharge valve 300,
discharge valve 400 and discharge valve 500 may be used in or with
linear compressors with planar springs rather than a machined
spring.
[0066] 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.
* * * * *