U.S. patent application number 13/094330 was filed with the patent office on 2012-03-15 for suction and discharge mechanisms for an appliance refrigerant compressor.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. Invention is credited to Ravindra Gopaldas Devi, Subhrajit Dey, Hiteshkumar Mistry.
Application Number | 20120063940 13/094330 |
Document ID | / |
Family ID | 45806889 |
Filed Date | 2012-03-15 |
United States Patent
Application |
20120063940 |
Kind Code |
A1 |
Devi; Ravindra Gopaldas ; et
al. |
March 15, 2012 |
SUCTION AND DISCHARGE MECHANISMS FOR AN APPLIANCE REFRIGERANT
COMPRESSOR
Abstract
Suction and discharge mechanisms for the compressor of a
refrigeration cycle are provided. Two discharge ports for the
removal of refrigerant from a compressor are described.
Additionally, the present invention can provide a suction valve
having an aperture for the flow of refrigerant around and through
the suction valve when it is in an open position. As such, the
present invention can provide a refrigerant compressor having an
improved coefficient of discharge and increased efficiency.
Inventors: |
Devi; Ravindra Gopaldas;
(Bangalore, IN) ; Dey; Subhrajit; (Bangalore,
IN) ; Mistry; Hiteshkumar; (Bangalore, IN) |
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
45806889 |
Appl. No.: |
13/094330 |
Filed: |
April 26, 2011 |
Current U.S.
Class: |
417/559 |
Current CPC
Class: |
F04B 39/1073
20130101 |
Class at
Publication: |
417/559 |
International
Class: |
F04B 53/10 20060101
F04B053/10 |
Claims
1. A refrigerant compressor, comprising: a cylinder for receipt of
refrigerant to be compressed; a piston received within said
cylinder and configured for reciprocating movement; a suction port
for the receipt of refrigerant into said cylinder; a suction valve
positioned at said suction port and configured for opening to allow
refrigerant through said suction port and into said cylinder; a
first discharge port for the discharge of refrigerant from said
cylinder; a second discharge port for the discharge of refrigerant
from said cylinder; and at least one discharge valve configured for
opening to allow refrigerant out of said cylinder through said
first and second discharge ports.
2. A refrigerant compressor as in claim 1, wherein said first and
second discharge ports are located on different sides of said
suction valve.
3. A refrigerant compressor as in claim 1, wherein said suction
valve includes an aperture positioned along said suction valve at a
location that is offset from said suction port, whereby refrigerant
is blocked from passing through the aperture when said suction
valve is in a closed position and refrigerant is allowed to pass
through the aperture when said suction valve in an open
position.
4. A refrigerant compressor as in claim 1, wherein at least one
discharge valve further comprises: a first discharge valve
positioned at said first discharge port and configured for opening
to a allow refrigerant out of said cylinder through said first
discharge port when said first discharge valve is an open position
and is configured for blocking refrigerant from discharging from
said cylinder when said first discharge valve is in a closed
position. a second discharge valve positioned at said second
discharge port and configured for opening to a allow refrigerant
out of said cylinder through said second discharge port when said
second discharge valve is an open position and is configured for
blocking refrigerant from discharging from said cylinder when said
second discharge valve is in a closed position.
5. A refrigerant compressor as in claim 1, wherein said suction
valve comprises a metal reed positioned so as to cover said suction
port when said suction valve is in a closed position.
6. A refrigerant compressor as in claim 1, wherein said at least
one discharge valve comprises a metal reed positioned so as to
cover said first and second discharge ports when said discharge
valve is in a closed position.
7. A refrigerant compressor as in claim 1, wherein said suction
valve comprises: a plate portion for blocking said suction port
when said suction valve is in a closed position, said plate portion
defining an aperture for the flow of refrigerant only when said
suction valve is in an open position; and, a stem portion.
8. A refrigerant compressor as in claim 7, wherein said suction
valve further comprises a metal reed.
9. A refrigerant compressor as in claim 1, wherein said first and
second discharge ports are defined by a suction valve plate
received at an opening at one end of said cylinder.
10. A valve mechanism for a refrigerant compressor, the compressor
having a cylinder defining an opening along one end, the valve
mechanism comprising: a suction valve plate for positioning at the
opening of the cylinder, said suction valve plate comprising: a
first discharge port configured for the discharge of refrigerant
from the cylinder; a second discharge port configured for the
discharge of refrigerant from the cylinder; and, a suction valve
for positioning proximate to a suction port and configured for
opening under suction to allow refrigerant through the suction port
and into the cylinder.
11. A valve mechanism for a refrigerant compressor as in claim 10,
wherein said suction valve comprises an aperture for the flow of
refrigerant when said suction valve is in an open position.
12. A valve mechanism for a refrigerant compressor as in claim 11,
wherein said suction valve is positioned between said first and
second discharge ports.
13. A valve mechanism for a refrigerant compressor as in claim 10,
wherein said suction valve comprises a metal reed positioned so as
to block the suction port when said suction valve is in a closed
position.
14. A valve mechanism for a refrigerant compressor as in claim 10,
wherein said suction valve further comprises: a plate portion for
blocking the suction port when said suction valve is in a closed
position, said plate portion defining an aperture for the flow of
refrigerant only when said suction valve is in an open position;
and, a stem portion.
15. A valve mechanism for a refrigerant compressor as in claim 14,
wherein said suction valve further comprises a metal reed.
16. A valve mechanism for a refrigerant compressor as in claim 10,
further comprising a discharge valve plate that comprises: a
discharge valve configured for opening to a allow refrigerant out
of the cylinder through said first and second discharge ports.
17. A valve mechanism for a refrigerant compressor as in claim 10,
wherein said discharge valve further comprises a metal reed.
18. A valve mechanism for a refrigerant compressor as in claim 10,
wherein said discharge valve plate is mounted onto said suction
valve plate.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to suction and discharge
mechanisms for the compressor of an appliance refrigeration
cycle.
BACKGROUND OF THE INVENTION
[0002] Refrigerant compressors are used in a variety of appliances
including refrigerators, freezers, and heat pump dryers.
Conventionally, such refrigerant compressors having a reciprocating
piston or other device for compressing refrigerant vapor to a
higher pressure within a cylinder or other chamber. After the
refrigerant is compressed by the stroke of the piston that reduces
the volume of the refrigerant within the cylinder, the refrigerant
is discharged through a single discharge port that is opened by a
discharge valve. During this compression stroke, a suction valve
for providing refrigerant into the cylinder through a suction port
is closed.
[0003] As the piston is withdrawn so as to increase the volume
available for refrigerant within the cylinder, refrigerant is drawn
through a single suction port that is opened by a suction valve. As
the refrigerant enters into the cylinder, it must flow through the
suction port and around the suction valve. During this intake
stroke, the discharge valve for the flow of refrigerant out of the
cylinder through the discharge port is closed.
[0004] The flow of refrigerant through the suction and discharge
ports as well as around the suction valve creates an undesirable
pressure drop in the refrigerant due to skin friction, shear flow
and expansion-contraction losses. A resultant energy loss occurs
that lowers the overall energy efficiency ratio (EER) of the
refrigerant compressor and, therefore, lowers the performance of
the appliance in which it operates. Stated alternatively,
additional energy is consumed in operating the compressor due to
these inefficiencies in a conventional refrigerant compressor.
[0005] Accordingly, a refrigerant compressor having suction and/or
discharge valves providing improved energy efficiency would be
beneficial. More particularly, suction and discharge valves that
can provide for a reduction in pressure drop owing to reduction in
friction losses and more streamlined flow would be useful. Such
valves that can provide an increased coefficient of discharge and
higher volumetric efficiency would also be particularly
beneficial.
BRIEF DESCRIPTION OF THE INVENTION
[0006] Aspects and advantages of the invention will be set forth in
part in the following description, or may be obvious from the
description, or may be learned through practice of the
invention.
[0007] In one exemplary embodiment, the present invention provides
a refrigerant compressor that includes a cylinder for receipt of
refrigerant to be compressed; a piston received within the cylinder
and configured for reciprocating movement; and a suction port for
the receipt of refrigerant into the cylinder. A suction valve is
positioned at the suction port and configured for opening to allow
refrigerant through the suction port and into the cylinder. A first
discharge port is provided for the discharge of refrigerant from
the cylinder. A second discharge port is also provided for the
discharge of refrigerant from the cylinder. At least one discharge
valve is configured for opening to allow refrigerant out of the
cylinder through the first and second discharge ports. The suction
valve can include an aperture for the flow through of
refrigerant.
[0008] In another exemplary embodiment, the present invention
provides a valve mechanism for a refrigerant compressor. The
compressor has a cylinder defining an opening along one end. The
valve mechanism includes a suction valve plate for positioning at
the opening of the cylinder. The suction valve plate includes a
first discharge port configured for the discharge of refrigerant
from the cylinder; a second discharge port configured for the
discharge of refrigerant from the cylinder; and a suction valve
located proximate to a suction port and configured for opening
under suction to allow refrigerant through the suction port and
into the cylinder. The suction valve can include an aperture for
the flow through of refrigerant.
[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, in which:
[0011] FIG. 1 provides an exemplary embodiment of a refrigerator
appliance as may be used with the present invention.
[0012] FIG. 2 is a schematic of an exemplary refrigeration cycle as
may be used with the present invention.
[0013] FIG. 3 is an exploded view of a refrigerant compressor
having conventional valve plates as will be further described
below.
[0014] FIG. 4 illustrates an exemplary suction valve plate of the
present invention as may be used with the exemplary refrigerant
compressor shown in FIG. 3.
[0015] FIG. 5 illustrates another exemplary suction valve plate of
the present invention as may be used with the exemplary refrigerant
compressor shown in FIG. 3.
[0016] FIG. 6 is a perspective view of the inlet from a suction
muffler providing refrigerant through an exemplary suction valve as
shown in FIG. 5. Also shown is a piston of the refrigerant
compressor.
[0017] FIG. 7 is a cross-sectional view of FIG. 6 taken along lines
7-7. However, a cylinder, rather than its piston, is shown in FIG.
7.
[0018] The use of similar or identical reference numerals in the
figures represents similar or identical features unless otherwise
indicated.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention relates to suction and discharge
mechanisms for the compressor of a refrigeration cycle. More
specifically, the present invention can provide two or more
discharge ports for the removal of refrigerant from a compressor as
opposed to the one port used in conventional compressors.
Additionally, the present invention can provide a suction valve
having an aperture for the flow of refrigerant around and through
the suction valve when it is in an open position. As such, the
present invention can provide a refrigerant compressor having an
improved coefficient of discharge and, therefore, increased
efficiency. In addition, compressor efficiency in conventional art
is further affected by an undesired phenomenon called flutter in
the suction and discharge valves. Flutter is primarily affected by
valve stiffness and damping owing to the valve shape, material,
thickness, valve connection to valve plate, and other factors.
These properties can be improved to reduce or eliminate the
flutter. In certain exemplary embodiments of the present invention,
the opening in the suction valve helps reduce the mass and alters
the stiffness and the damping properties both due to material and
fluid flow through the valve. Also, in certain exemplary
embodiments, the multiple discharge ports and valves help reduce
the flow area per port and hence results in smaller discharge
valves with smaller mass.
[0020] 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.
[0021] FIG. 1 provides a front view of a representative
refrigerator 10 in an exemplary embodiment of the present
invention. More specifically, for illustrative purposes, the
present invention is described with a refrigerator 10 having a
construction as shown and described further below. As used herein,
a refrigerator includes appliances such as a freezer,
refrigerator/freezer combination, compact, and any other style or
model of a refrigerator. Accordingly, other configurations
including multiple and different styled compartments could be used
with refrigerator 10, it being understood that the configuration
shown in FIG. 1 is by way of example only. Additionally, the
refrigerant compressor of the present invention is not limited to
use with a refrigerator appliance and may be used with other
appliances as well including e.g., a heat pump dryer.
[0022] Refrigerator 10 includes a fresh food storage compartment 12
and a freezer storage compartment 14. Freezer compartment 14 and
fresh food compartment 12 are arranged side-by-side within an outer
case 16 and defined by inner liners 18 and 20 therein. A space
between case 16 and liners 18 and 20, and between liners 18 and 20,
is filled with foamed-in-place insulation. Outer case 16 normally
is formed by folding a sheet of a suitable material, such as
pre-painted steel, into an inverted U-shape to form the top and
side walls of case 16. A bottom wall of case 16 normally is formed
separately and attached to the case side walls and to a bottom
frame that provides support for refrigerator 10. Inner liners 18
and 20 are molded from a suitable plastic material to form freezer
compartment 14 and fresh food compartment 12, respectively.
Alternatively, liners 18, 20 may be formed by bending and welding a
sheet of a suitable metal, such as steel. The illustrative
embodiment includes two separate liners 18, 20 as it is a
relatively large capacity unit and separate liners add strength and
are easier to maintain within manufacturing tolerances. In smaller
refrigerators, a single liner is formed and a mullion 24 spans
between opposite sides of the liner to divide it into a freezer
compartment and a fresh food compartment.
[0023] A breaker strip 22 extends between a case front flange and
outer front edges of liners 18, 20. Breaker strip 22 is formed from
a suitable resilient material, such as an extruded
acrylo-butadiene-styrene based material (commonly referred to as
ABS). The insulation in the space between liners 18, 20 is covered
by another strip of suitable resilient material, which also
commonly is referred to as a mullion 24. In one embodiment, mullion
24 is formed of an extruded ABS material. Breaker strip 22 and
mullion 24 form a front face, and extend completely around inner
peripheral edges of case 16 and vertically between liners 18, 20.
Mullion 24, insulation between compartments, and a spaced wall of
liners separating compartments, sometimes are collectively referred
to herein as a center mullion wall 26. In addition, refrigerator 10
includes shelves 28 and slide-out storage drawers 30, sometimes
referred to as storage pans, which normally are provided in fresh
food compartment 12 to support items being stored therein.
[0024] Refrigerator 10 can be controlled by a microprocessor (not
shown) or other processing device according to user preference via
manipulation of a control interface 32 mounted in an upper region
of fresh food storage compartment 12 and coupled to the
microprocessor. A shelf 34 and wire baskets 36 are also provided in
freezer compartment 14. In addition, an ice maker 38 may be
provided in freezer compartment 14.
[0025] A freezer door 42 and a fresh food door 44 close access
openings to freezer and fresh food compartments 14, 12,
respectively. Each door 42, 44 is mounted to rotate about its outer
vertical edge between an open position, as shown in FIG. 1, and a
closed position (not shown) closing the associated storage
compartment. Freezer door 42 includes a plurality of storage
shelves 46, and fresh food door 44 includes a plurality of storage
shelves 48.
[0026] Refrigerator 10 includes a machinery compartment that
incorporates at least part of a refrigeration cycle 50 as shown in
FIG. 2. The components of refrigeration cycle 50 include a
refrigerant compressor unit 52, a condenser 54, valves 56 and 58,
and an evaporator 60--all connected in series and charged with a
refrigerant. Evaporator 60 is also a type of heat exchanger that
transfers heat from air passing over the evaporator 60 to a
refrigerant flowing through evaporator 60, thereby causing the
refrigerant to vaporize. As such, cooled air is produced and
configured to refrigerate compartments 12, 14 of refrigerator
10.
[0027] From evaporator 60, vaporized refrigerant flows to
compressor unit 52, which increases the pressure of the
refrigerant. This compression of the refrigerant raises its
temperature, which is subsequently lowered by passing the gaseous
refrigerant through condenser 54 where heat exchange with ambient
air takes place so as to cool the refrigerant. Valves 56 and 58
further reduce the pressure of refrigerant leaving condenser 54
before being fed as a liquid to evaporator 60. The refrigeration
cycle 50 depicted in FIG. 2 is provided by way of example only. It
is within the scope of the present invention for other
configurations of the refrigeration system 50 to be used as
well.
[0028] FIG. 3 provides an exploded view of an exemplary embodiment
of a refrigerant compressor 52. The present invention is not
limited to use with the compressor shown in FIG. 3 as other
configurations for the compressor may be used as well. As shown,
compressor 52 includes a suction muffler 100 (to help reduce noise
emissions from the intake of refrigerant) that is connected to head
cover 105. A head gasket 110 is positioned between head cover 105
and a discharge valve plate 115.
[0029] Discharge valve plate 115 has a suction port 150 for the
flow of refrigerant into cylinder 135 through an opening 136 at the
end of cylinder 135. Discharge valve plate 115 also includes a
discharge valve 145 that controls the discharge of refrigerant from
cylinder 135 though a discharge port 155 located in suction valve
plate 120. Discharge valve 145 is constructed from a metal reed
that includes a plate portion 146 that closes (i.e. blocks)
discharge port 155 when valve 145 is in a closed position.
Typically, discharge valve 145 is assisted by a compression spring
(not shown). Accordingly, when a piston (not shown) in cylinder 135
compresses refrigerant by decreasing the volume available,
eventually the pressure increases and overcomes discharge valve 145
and its associated compression spring so as to move discharge valve
145 into an open position and allow the discharge of refrigerant
from cylinder 135 through discharge port 155.
[0030] Discharge valve plate 115 is connected to suction valve
plate 120. For purposes of explaining differences between the
present invention and conventional compressor units, suction valve
plate 120 is shown with a conventional suction valve 190 and a
single discharge port 155. Typically, suction valve 190 is
constructed from a metal reed that includes a plate portion 192
that closes or blocks the flow of refrigerant through suction port
150 when in the closed position.
[0031] When a piston (not shown) in cylinder 135 draws a suction by
increasing the volume available in cylinder 135, the vacuum
eventually overcomes suction valve 190 (and any associated spring)
so that valve 190 moves to an open position whereby refrigerant is
allowed through suction port 150, around plate portion 192 of valve
190, through opening 136, and into cylinder 135 where the
refrigerant will be subsequently compressed to discharge as
described above. Suction valve plate 120 is sealed with compressor
pump 140 by gasket 125. A plurality of mounting apertures 101 are
shown in each of the parts described above whereby fasteners (e.g.,
threaded bolts) may be used to connect the same to pump unit
140.
[0032] FIG. 4 provides an exemplary embodiment of a suction valve
plate 220 of the present invention. Plate 220 includes mounting
apertures 201 whereby plate 220 may be substituted for the
conventional plate 120 shown with the compressor unit 52 of FIG. 3.
Unlike suction valve plate 120 of FIG. 3, however, suction valve
plate 220 includes two discharge ports. More specifically, plate
220 includes a first discharge port 255 and a second discharge port
256. As such, compared to plate 120, suction valve plate 220 can
increase (e.g., double) the cross-sectional area available for the
discharge of refrigerant from cylinder 135. Such increased
discharge space provides for decreased pressure drop and improves
the coefficient of discharge of the compressor 52, increases its
volumetric efficiency, and provides higher energy efficiency as
compared to plate 120. A single discharge valve 145 may be used for
both first and second discharge ports 255 and 256. Alternatively,
discharge valve plate 115 may be equipped with separate discharge
valves for each of ports 255 and 256.
[0033] The present invention is not limited to only two discharge
ports 255 and 256 as shown in FIG. 4. Additional ports may be also
be utilized depending upon, e.g., the structural strength of the
material used for the construction of suction valve plate 220.
Furthermore, although shown as two, equally-sized circular ports
255 and 256 located on both sides of a suction valve 290, other
configurations, shapes and sizes may be used as well.
[0034] FIG. 5 illustrates another exemplary embodiment of a suction
valve plate 320 of the present invention. Plate 320 includes
mounting apertures 301 whereby plate 320 may be substituted for
conventional plate 120 shown with the compressor 52 of FIG. 3. Like
the suction valve plate 120 of FIG. 3, plate 320 includes a single
discharge port 355 along one side of a suction valve 390. However,
unlike plate 120, suction valve plate 320 includes an aperture 391
in suction valve 320 whereby refrigerant may flow through suction
valve 320, in addition to the conventional path around the suction
valve, when it is in an open position to allow refrigerant into
cylinder 135. As shown in FIG. 5, suction valve 390 includes a
plate portion 392 and a stem portion 363. Plate portion 392 blocks
suction port 150 when suction valve 390 is in a closed position.
However, when in an open position, refrigerant can flow through
aperture 391 as well as around suction valve 390 so as to provide
improved efficiency.
[0035] More specifically, and by way of further description, FIGS.
6 and 7 provide an illustration of the flow of refrigerant (arrows
I) through the inlet 370 of suction muffler 100, through suction
port 150, and into cylinder 135. Refrigerant is drawn into cylinder
135 when piston 130 moves in the direction of arrow D so as to
reduce the pressure by expanding the space available for
refrigerant in cylinder 135. As refrigerant flows into cylinder
135, refrigerant can flow both around suction valve 390 (arrow A)
as well as through aperture 391 (arrow T) when valve 390 is in an
open position. Note that with suction valve 190, refrigerant can
only flow around and not through valve 190. Accordingly, suction
valve 390 increases the cross-sectional area available for the
suction of refrigerant into cylinder 135. Such increased suction
capability can provide for a decreased pressure drop due to lower
friction losses and better streamlined flow to improve the
coefficient of discharge of the compressor 52, increase its
volumetric efficiency, and provide a higher energy efficiency as
compared to suction valve plate 120.
[0036] As with plate 220, the present invention is not limited to
suction valve plate 320 having a valve 390 and aperture 391 shaped
and positioned only as shown in FIG. 6. Other configurations and
shapes may be used as well.
[0037] Additionally, for purposes of clarity in describing the
present invention, two suction plates 220 and 320 have been shown
separately. However, using the teachings disclosed herein, it will
be understood by one of skill in the art that a suction valve plate
having both an improved suction valve 390 (with aperture 391) as
well as multiple discharge ports 255 and 256 may be provided as
well.
[0038] 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.
* * * * *