U.S. patent application number 14/053680 was filed with the patent office on 2015-04-16 for refrigerator appliance and a method for manufacturing the same.
This patent application is currently assigned to General Electric Company. The applicant listed for this patent is General Electric Company. Invention is credited to Todd Duncan Cook.
Application Number | 20150102716 14/053680 |
Document ID | / |
Family ID | 52809116 |
Filed Date | 2015-04-16 |
United States Patent
Application |
20150102716 |
Kind Code |
A1 |
Cook; Todd Duncan |
April 16, 2015 |
REFRIGERATOR APPLIANCE AND A METHOD FOR MANUFACTURING THE SAME
Abstract
The present subject matter provides a refrigerator appliance and
a method for manufacturing the same. The method includes applying a
polyurethane elastomer onto a surface of an inner liner of the
refrigerator appliance and injecting a polyurethane foam into a
cavity defined between an outer case of the refrigerator appliance
and the inner liner. The polyurethane elastomer can limit or
prevent leakage of the polyurethane foam from the cavity.
Inventors: |
Cook; Todd Duncan; (Cecilia,
KY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company |
Schenectady |
NY |
US |
|
|
Assignee: |
General Electric Company
Schenectady
NY
|
Family ID: |
52809116 |
Appl. No.: |
14/053680 |
Filed: |
October 15, 2013 |
Current U.S.
Class: |
312/401 ;
29/428 |
Current CPC
Class: |
Y10T 29/49826 20150115;
F25D 23/066 20130101 |
Class at
Publication: |
312/401 ;
29/428 |
International
Class: |
F25D 23/08 20060101
F25D023/08; F25D 23/06 20060101 F25D023/06 |
Claims
1. A method for assembling a refrigerator appliance, comprising:
providing an outer case of the refrigerator appliance and an inner
liner of the refrigerator appliance; mounting the inner liner to
the outer case such that the inner liner and the outer case define
a cavity therebetween; applying a polyurethane elastomer onto a
surface of the inner liner; and injecting a polyurethane foam into
the cavity between the outer case and the inner liner.
2. The method of claim 1, further comprising heating the outer
case, the inner liner and the polyurethane elastomer prior to said
step of injecting.
3. The method of claim 1, wherein the inner liner comprises a first
portion and a second portion, the first and second portions of the
inner liner mounted to each other such that the first and second
portions of the inner liner define a seam therebetween, wherein
said step of applying comprises applying the polyurethane elastomer
onto the inner liner at the seam of the inner liner.
4. The method of claim 1, wherein the inner liner defines an
opening, wherein said step of applying comprises applying the
polyurethane elastomer onto the inner liner at the opening of the
inner liner.
5. The method of claim 1, further comprising attaching a rear panel
to the outer case after said step of applying and prior to said
step of injecting.
6. The method of claim 1, wherein the polyurethane elastomer has a
temperature between about sixty-five degrees Fahrenheit and about
one-hundred degrees Fahrenheit during said step of applying.
7. The method of claim 1, wherein the inner liner defines an
interior volume of the refrigerator appliance, wherein said step of
applying comprises applying the polyurethane elastomer onto the
surface of the inner liner such that the polyurethane elastomer on
the surface of the inner liner hinders the polyurethane foam from
entering the interior volume of the inner liner during said step of
injecting.
8. The method of claim 1, wherein said step of applying comprises
applying the polyurethane elastomer onto the surface of the inner
liner with a wand having a spray head, the wand having a length
about equal to a depth of the cavity between the inner liner and
the outer case.
9. The method of claim 1, wherein the polyurethane elastomer has a
temperature less than a melting temperature of the inner liner
during said step of applying.
10. The method of claim 1, further comprising curing the
polyurethane foam within the cavity between the outer case and the
inner liner such that the polyurethane foam extends between the
inner liner and the outer case within the cavity after said step of
curing.
11. A refrigerator appliance, comprising: an outer case; an inner
liner spaced apart from the outer case such that the inner liner
and the outer case define a cavity therebetween, the inner liner
defining an interior volume configured for receipt of food items
for storage; a polyurethane elastomer positioned on a surface of
the inner liner; and a polyurethane foam disposed within the cavity
between the outer case and the inner liner, the polyurethane foam
contacting the polyurethane elastomer, the inner liner and the
outer case within the cavity.
12. The appliance of claim 11, wherein the inner liner comprises a
first portion and a second portion, the first and second portions
of the inner liner mounted to each other, the first and second
portions of the inner liner defining a seam therebetween, the
polyurethane elastomer positioned on the inner liner at the seam
between the first and second portions of the inner liner such that
the polyurethane elastomer is disposed between the polyurethane
foam and the seam between the first and second portions of the
inner liner.
13. The appliance of claim 12, wherein the first and second potions
of the inner liner define a fresh food chamber.
14. The appliance of claim 12, wherein the first portion of the
inner liner defines a fresh food chamber and the second potion of
the inner liner defines a freezer chamber.
15. The appliance of claim 11, wherein the inner liner defines an
opening that extends between the interior volume of the inner liner
and the polyurethane elastomer, the polyurethane elastomer
positioned on the inner liner at the opening of the inner liner
such that the polyurethane elastomer is disposed between the
polyurethane foam and the opening of the inner liner.
16. The appliance of claim 11, further comprising a rear panel
mounted to the outer case such that the rear panel and the inner
liner are spaced apart from each other, the inner liner, the outer
case and the rear panel defining the cavity therebetween.
17. The appliance of claim 16, wherein the polyurethane foam
extends between the inner liner, the outer case and the rear panel
within the cavity.
18. The appliance of claim 11, wherein the polyurethane foam is a
rigid closed cell polyurethane foam.
Description
FIELD OF THE INVENTION
[0001] The present subject matter relates generally to refrigerator
appliances and methods for manufacturing the same.
BACKGROUND OF THE INVENTION
[0002] Certain refrigerator appliances include double wall cabinets
with inner liners and outer cases. In such refrigerator appliances,
the inner liner and the outer case are spaced apart and define a
cavity therebetween. An expandable foam material, such as a
polyurethane foam, can be injected into the cavity between the
inner liner and the outer case of the double wall cabinet in order
to provide insulation within the double wall cabinet.
[0003] During expansion of the foam material, the expandable foam
material fills the cavity between the inner liner and the outer
case of the double wall cabinet. However, the expandable foam
material can also leak out of the cavity at a seam between the
inner liner and the outer case or at holes or openings in the inner
liner or outer case, and the leaked foam material can cure on the
inner liner, the outer case or other components of the refrigerator
appliance. Removing such leaked foam material can be difficult and
time consuming. In extreme cases, a refrigerator appliance is
scrapped if removing such leaked foam material is impracticable or
infeasible.
[0004] To limit or prevent leaks of the foam material, certain
refrigerator appliances include an Olefin based thermoplastic
positioned at the seam between the inner liner and the outer case
or at holes or openings in the inner liner or outer case. However,
the Olefin material bonds poorly to the inner liner and the outer
case. Further, the Olefin material is dispensed at relatively high
temperatures and accurately dispensing the Olefin material can be
difficult. In particular, the inner liner can melt if the Olefin
material's dispenser contacts the inner liner or is positioned next
to the inner liner for an extended period of time.
[0005] Accordingly, a refrigerator appliance with features for
limiting or preventing leaking of insulating foam material from a
cavity of the refrigerator appliance would be useful. Further, a
method for manufacturing a refrigerator appliance that avoids
leaking of insulating foam material from a cavity of the
refrigerator appliance would be useful. In particular, a method for
manufacturing a refrigerator appliance that avoids leaking of
insulating foam material from a cavity of the refrigerator
appliance while avoiding the problems discussed above would be
useful.
BRIEF DESCRIPTION OF THE INVENTION
[0006] The present subject matter provides a refrigerator appliance
and a method for manufacturing the same. The method includes
applying a polyurethane elastomer onto a surface of an inner liner
of the refrigerator appliance and injecting a polyurethane foam
into a cavity defined between an outer case of the refrigerator
appliance and the inner liner. The polyurethane elastomer can limit
or prevent leakage of the polyurethane foam from the cavity.
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 method for assembling a
refrigerator appliance is provided. The method includes providing
an outer case of the refrigerator appliance and an inner liner of
the refrigerator appliance, mounting the inner liner to the outer
case such that the inner liner and the outer case define a cavity
therebetween, applying a polyurethane elastomer onto a surface of
the inner liner, and injecting a polyurethane foam into the cavity
between the outer case and the inner liner.
[0008] In a second exemplary embodiment, a refrigerator appliance
is provided. The refrigerator appliance includes an outer case and
an inner liner spaced apart from the outer case such that the inner
liner and the outer case define a cavity therebetween. The inner
liner defines an interior volume configured for receipt of food
items for storage. A polyurethane elastomer is positioned on a
surface of the inner liner. A polyurethane foam is disposed within
the cavity between the outer case and the inner liner. The
polyurethane foam contacts the polyurethane elastomer, the inner
liner and the outer case within the cavity.
[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 a front, elevation view of a refrigerator
appliance according to an exemplary embodiment of the present
subject matter.
[0012] FIG. 2 provides a front, elevation view of the exemplary
refrigerator appliance of FIG. 1 with doors of the exemplary
refrigerator appliance shown in an open position to reveal a fresh
food chamber of the exemplary refrigerator appliance.
[0013] FIGS. 3, 4, 5 and 6 provide bottom perspective views of the
exemplary refrigerator appliance of FIG. 1 with the exemplary
refrigerator appliance shown in various stages of manufacture.
[0014] FIG. 7 illustrates a method for manufacturing a refrigerator
appliance according to an exemplary embodiment of the present
subject matter.
DETAILED DESCRIPTION
[0015] 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.
[0016] FIG. 1 provides a front, elevation view of a refrigerator
appliance 100 according to an exemplary embodiment of the present
subject matter with refrigerator doors 128 of the refrigerator
appliance 100 shown in a closed position. FIG. 2 provides a front
view of refrigerator appliance 100 with refrigerator doors 128
shown in an open position to reveal a fresh food chamber 122 of
refrigerator appliance 100.
[0017] Refrigerator appliance 100 includes a cabinet or housing 120
that extends between a top portion 101 and a bottom portion 102
along a vertical direction V. Housing 120 defines chilled chambers
for receipt of food items for storage. In particular, housing 120
defines fresh food chamber 122 positioned at or adjacent top 101 of
housing 120 and a freezer chamber 124 arranged at or adjacent
bottom 102 of housing 120. As such, refrigerator appliance 100 is
generally referred to as a bottom mount refrigerator. It is
recognized, however, that the benefits of the present disclosure
apply to other types and styles of refrigerator appliances such as,
e.g., a top mount refrigerator appliance or a side-by-side style
refrigerator appliance. Consequently, the description set forth
herein is for illustrative purposes only and is not intended to be
limiting in any aspect to any particular refrigerator chamber
configuration.
[0018] Refrigerator doors 128 are rotatably hinged to an edge of
housing 120 for selectively accessing fresh food chamber 122. In
addition, a freezer door 130 is arranged below refrigerator doors
128 for selectively accessing freezer chamber 124. Freezer door 130
is coupled to a freezer drawer (not shown) slidably mounted within
freezer chamber 124. As discussed above, refrigerator doors 128 and
freezer door 130 are shown in the closed configuration in FIG. 1,
and refrigerator doors 128 are shown in the open position in FIG.
2.
[0019] Turning now to FIG. 2, various storage components are
mounted within fresh food chamber 122 to facilitate storage of food
items therein as will be understood by those skilled in the art. In
particular, the storage components include bins 140, drawers 142,
and shelves 144 that are mounted within fresh food chamber 122.
Bins 140, drawers 142, and shelves 144 are configured for receipt
of food items (e.g., beverages and/or solid food items) and may
assist with organizing such food items. As an example, drawers 142
can receive fresh food items (e.g., vegetables, fruits, and/or
cheeses) and increase the useful life of such fresh food items.
[0020] FIGS. 3, 4, 5 and 6 provide bottom perspective views of
refrigerator appliance 100 with refrigerator appliance 100 shown in
various stages of manufacture. As may be seen in FIGS. 3, 4 and 5,
refrigerator appliance 100 includes an inner liner 160 and an outer
case 150. Inner liner 160 and outer case 150 are components of
housing 120 and are assembled together to form housing 120 as
discussed in greater detail below. As may be seen in FIGS. 3-6,
outer case 150 is exposed such that outer case 150 can correspond
to an outermost layer of housing 120. Outer case 150 may be formed
by folding a sheet of a suitable material, such as pre-painted
steel, into an inverted U-shape to form top and side walls of outer
case 150.
[0021] Inner liner 160 is positioned within outer case 150 and
defines the chilled chambers of housing 120. In particular, inner
liner 160 defines fresh food chamber 122 and freezer chamber 124 of
housing 120. Inner liner 160 can be formed from any suitable
material, such as molded plastic. In certain exemplary embodiments,
inner liner 160 is a single, integral component that defines both
fresh food chamber 122 and freezer chamber 124. In alternative
exemplary embodiments, inner liner 160 is constructed with multiple
components (e.g., at least two components) that are connected or
mounted to one another to define fresh food chamber 122 and freezer
chamber 124 as discussed in greater detail below.
[0022] Inner liner 160 is mounted or secured to outer case 150. In
particular, inner liner 160 may be mounted to outer case 150 such
that inner liner 160 and outer case 150 are spaced apart from each
other and inner liner 160 and outer case 150 define a cavity 170
therebetween. Inner liner 160 may be mounted to outer case 150
using any suitable mechanism. For example, fasteners can be
extended through flanges of inner liner 160 and outer case 150 at a
front portion 104 of refrigerator appliance 100. In alternative
exemplary embodiments, heat staking, ultrasonic welding, snap fit,
or any other suitable mechanism may be used to mount inner liner
160 to outer case 150.
[0023] As may be seen in FIG. 3, inner liner 160 may include a
first portion 162 and a second portion 164. The first and second
portions 162 and 164 of inner liner 160 can cooperate to define
chilled chambers of housing 120. As an example, first and second
portions 162 and 164 of inner liner 160 may cooperate to define
fresh food chamber 122 of housing 120. As another example, first
portion 162 of inner liner 160 may define fresh food chamber 122,
and second potion 164 of inner liner 160 may define freezer chamber
124. First and second portions 162 and 164 of inner liner 160 are
mounted to each other such that first and second portions 162 and
164 of inner liner 160 define a seam 166 therebetween, e.g., where
first and second portions 162 and 164 of inner liner 160 meet and
engage each other.
[0024] Inner liner 160 defines an interior volume 169 (FIG. 2),
such as fresh food chamber 122 or freezer chamber 124, configured
for receipt of food items for storage. Inner liner 160 also defines
at least one hole or opening 168. Openings 168 extend through inner
liner 160, e.g., from a surface 161 of inner liner 160 to interior
volume 169 defined by inner casing 160. Various components of
refrigerator appliance 100 can extend from cavity 170 through
openings 168 and other holes in inner liner 160 in order to
position such components in interior volume 169 of inner liner 160.
For example, a light emitter 172 is mounted to inner liner 160 at
one of openings 168 of inner liner 160. Light emitter 172 is
configured for directing light into interior volume 169 of inner
liner 160. Similarly, a temperature sensor 173 is mounted to inner
liner 160 at one of openings 168 of inner liner 160 and is
configured for measuring a temperature of interior volume 169. As
another example, a drain pipe 174 is mounted to inner liner 160 and
may extend through one of openings 168 of inner liner 160. Drain
pipe 172 is configured for directing liquids, such as liquid water
from a defrost cycle, out of interior volume 169 of inner liner
160. As yet another example, mounting brackets 176 for storage
components within fresh food chamber 122 are mounted to inner liner
160 and can include fasteners that extend through inner liner 160
at one of openings 168 of inner liner 160.
[0025] As may be seen in FIG. 6, refrigerator appliance 100 also
includes a rear panel 180. Rear panel 180 is mounted to outer case
150. In particular, rear panel 180 is mounted to outer case 150
such that rear panel 180 is spaced apart from inner liner 160. With
rear panel 180 mounted to outer case 150, rear panel 180 assists
with defining cavity 170. In particular, inner liner 160, outer
case 150 and rear panel 180 can cooperate to define cavity 170
therebetween.
[0026] Refrigerator appliance 100 also includes a machinery
compartment 151. A sealed system (not shown) for cooling air within
chilled chambers of housing 120 may be positioned within machinery
compartment 151. The sealed system includes components for
executing a known vapor compression cycle for cooling air. The
components include a compressor, a condenser, an expansion device,
and an evaporator connected in series as a loop and charged with a
refrigerant. The evaporator is a type of heat exchanger which
transfers heat from air passing over the evaporator to the
refrigerant flowing through the evaporator, thereby causing the
refrigerant to vaporize. The cooled air is used to refrigerate one
or more of the chilled chambers via fans. The construction and
operation of the sealed system are well known to those skilled in
the art.
[0027] To insulate chilled chambers of housing 120, such as fresh
food chamber 122 and freezer chamber 124, polyurethane foam 192 is
disposed within cavity 170. A portion of rear panel 180 is removed
in FIG. 6 to show polyurethane foam 192 within cavity 170.
Polyurethane foam 192 within cavity 170 can extend between and
adhere to outer case 150, inner liner 160 and/or rear panel 180.
Polyurethane foam 192 can hinder heat transfer to the chilled
chambers of housing 120. In addition, polyurethane foam 192 can be
a rigid, e.g., closed cell, polyurethane foam such that
polyurethane foam 192 also enhances a structural rigidity of
housing 120. For example, polyurethane foam 192 can hinder racking
or other movement of housing 120 by extending between and/or
adhering to at least one of outer case 150, inner liner 160 and
rear panel 180.
[0028] As discussed above, inner liner 160 include seam 166 and
openings 168. During curing of polyurethane foam 192, polyurethane
foam 192 expands and can flow through seam 166 and/or openings 168
into interior volume 169 of inner liner 160. Removing excess
polyurethane foam 192 from inner liner 160 within interior volume
169 can be difficult and/or time consuming. Thus, refrigerator
appliance 100 includes features for limiting or preventing
polyurethane foam 192 from leaking into unwanted areas, such as
machinery compartment 151 or interior volume 169 of inner liner
160. In particular, refrigerator appliance 100 includes features
for limiting or preventing polyurethane foam 192 from leaking
through seam 166 and/or openings 168.
[0029] As may be seen in FIGS. 4 and 5, refrigerator appliance 100
includes a polyurethane elastomer 190 positioned on a surface 161
of inner liner 160. Polyurethane elastomer 190 is applied at
various locations on surface 161 of inner liner 160 in order to
hinder or prevent leakage of polyurethane foam 192, e.g., out of
cavity 170. In particular, polyurethane elastomer 190 may be
applied at seam 166 of inner liner 160 to hinder or prevent leakage
of polyurethane foam 192 at seam 166, e.g., during injection or
curing of polyurethane foam 192. For example, polyurethane
elastomer 190 may be positioned on inner liner 160 at seam 166 such
that polyurethane elastomer 190 is disposed between polyurethane
foam 192 and seam 166 of inner liner 160. Similarly, polyurethane
elastomer 190 may be applied at openings 168 of inner liner 160 to
hinder or prevent leakage of polyurethane foam 192 at openings 168,
e.g., during injection or curing of polyurethane foam 192. For
example, polyurethane elastomer 190 may be positioned on inner
liner 160 at openings 168 such that polyurethane elastomer 190 is
disposed between polyurethane foam 192 and openings 168. In such a
manner, polyurethane foam 192 can contact or impact polyurethane
elastomer 190 such that polyurethane elastomer 190 blocks
polyurethane foam 192 from leaking out of cavity 170 during curing
of polyurethane foam 192. In a similar manner, polyurethane
elastomer 190 can also limit or prevent leaking of polyurethane
foam 192 out of cavity 170 into machinery compartment 151.
[0030] It should be understood that both polyurethane elastomer 190
and polyurethane foam 192 can be thermoset resins. Thus, once
cured, polyurethane elastomer 190 and polyurethane foam 192 may not
be melted. However, polyurethane foam 192 can include a foaming
agent, such as cyclopentane or another suitable material. The
foaming agent can boil at a polymerization temperature of reactants
used to create polyurethane foam 192, and the foaming agent can
create leavening within polyurethane foam 192 such that
polyurethane foam 192 includes gaseous phase material disposed
therein. Conversely, polyurethane elastomer 190 may not contain a
volatile component such that nothing boils at a polymerization
temperature of reactants used to create polyurethane elastomer 190.
Accordingly, polyurethane elastomer 190 can be significantly denser
than polyurethane foam 192. Further, polyurethane elastomer 190 is
an elastomer. Conversely, polyurethane foam 192 can be a rigid
foam. Thus, a Young's modulus of polyurethane elastomer 190 can be
significantly less than a Young's modulus of polyurethane foam 192,
and polyurethane elastomer 190 can be significantly more flexible
than polyurethane foam 192.
[0031] FIG. 7 illustrates a method 700 for manufacturing a
refrigerator appliance according to an exemplary embodiment of the
present subject matter. Method 700 can be used manufacture any
suitable refrigeration appliance. As an example, method 700 may be
used to manufacture or assemble refrigerator appliance 100. Thus,
method 700 is discussed in greater detail below in the context of
FIGS. 3, 4, 5 and 6. Utilizing method 700, leakage of polyurethane
foam 192 within refrigerator appliance 100 can be limited or
prevented as discussed in greater detail below.
[0032] At step 710, outer case 150 of refrigerator appliance 100
and inner liner 160 of refrigerator appliance 100 are provided. As
discussed above, inner liner 160 and outer case 150 are components
of housing 120, and inner liner 160 and outer case 150 are
assembled together to form housing 120. At step 720, inner liner
160 is mounted to outer case 150. In particular, inner liner 160
may be mounted to outer case 150 such that inner liner 160 and
outer case 150 are spaced apart from each other and inner liner 160
and outer case 150 define cavity 170 therebetween.
[0033] At step 730, polyurethane elastomer 190 is applied onto
surface 161 of inner liner 160. For example, as shown in FIG. 4,
polyurethane elastomer 190 may be applied onto inner liner 160 at
seam 166 of inner liner 160 at step 730. In such a manner,
polyurethane elastomer 190 can seal seam 166 of inner liner 160 at
step 730. As another example, polyurethane elastomer 190 may be
applied onto inner liner 160 at openings 168 of inner liner 160 at
step 730. In such a manner, polyurethane elastomer 190 can seal
openings 168 of inner liner 160 at step 730. In a similar manner,
polyurethane elastomer 190 can be applied onto surface 161 of inner
liner 160 such that polyurethane elastomer 190 on surface 161 of
inner liner 160 hinders or prevents polyurethane foam 192 from
leaking into machinery compartment 151 at step 730.
[0034] Polyurethane elastomer 190 can be applied onto surface 161
of inner liner 160 using any suitable method or mechanism at step
730. For example, polyurethane elastomer 190 may be applied onto
surface 161 of inner liner 160 manually or with a manually operated
spray gun, or polyurethane elastomer 190 may extruded onto surface
161 of inner liner 160. As another example, an automated spray
assembly 200 (FIG. 4) may be used to apply polyurethane elastomer
190 onto surface 161 of inner liner 160 at step 730. Automated
spray assembly 200 can programmed or configured to apply
polyurethane elastomer 190 at any suitable location on inner liner
160, e.g., according to a predefined application pattern. For
example, as shown in FIG. 4, automated spray assembly 200 may
programmed or configured to apply polyurethane elastomer 190 onto
seam 166 of inner liner 160.
[0035] Automated spray assembly 200 includes a wand 202 and a spray
head 204. Spray head 204 is mounted at a distal end 206 of wand
202. Polyurethane elastomer 190 exits automated spray assembly 200
at spray head 204 during application of polyurethane elastomer 190
with automated spray assembly 200 at step 730. To assist with
applying polyurethane elastomer 190, wand 202 is sized for
extending into cavity 170. In particular, as shown in FIG. 4, wand
202 has a length L that is greater than or about equal to a depth D
of cavity 170. Thus, wand 202 can be positioned within cavity 170,
and spray head 204 can apply polyurethane elastomer 190 at all or
almost all locations within cavity 170. In particular, wand 202 can
extend through cavity 170 to apply polyurethane elastomer 190 at or
adjacent front portion 104 of housing 120, e.g., where outer case
150 and inner liner 160 are mounted to each other.
[0036] During step 730, polyurethane elastomer 190 can have any
suitable temperature. For example, polyurethane elastomer 190 may
have a temperature less than a melting temperature of inner liner
160 during step 730. In such a manner, damage to inner liner 160
due to application of polyurethane elastomer 190 can be avoided or
limited. In certain exemplary embodiments, polyurethane elastomer
190 has a temperature that is about equal to room temperature,
e.g., between about sixty-five degrees Fahrenheit and about
one-hundred degrees Fahrenheit, during step 730. Relatively low
temperature application of polyurethane elastomer 190 also permits
placement of spray head 204 adjacent inner liner 160 within cavity
170 during application of polyurethane elastomer 190 at step 730
because at such temperatures spray head 204 is unlikely to damage
inner liner 160, e.g., by melting inner liner 160.
[0037] At step 740, rear panel 180 is attached to outer case 150.
In such a manner, cavity 170 can be sealed or fully defined with
rear panel 180. At step 750, outer case 150 and inner liner 160
(e.g., and rear panel 180) are heated. During step 750,
polyurethane elastomer 190 is also heated. Such elements are heated
at step 750 in order to prepare such elements for application or
injection of polyurethane foam 192. In addition, heating of
polyurethane elastomer 190 at step 750 can also assist with curing
polyurethane elastomer 190 prior to subsequent steps of method
700.
[0038] At step 760, polyurethane foam 192 is injected into cavity
170 between outer case 150 and inner liner 160. At step 770,
polyurethane foam 192 within cavity 170 is cured. During step 770,
polyurethane foam 192 expands such that polyurethane foam 192
extends between and adheres to inner liner 160 and outer case 150
(e.g., and rear panel 180) within cavity 170. Polyurethane
elastomer 190 can limit or prevent leakage of polyurethane foam 192
out of cavity 170 during step 770. For example, polyurethane
elastomer 190 can block polyurethane foam 192 at seam 166 and/or
openings 168 and limit or prevent leakage of polyurethane foam 192
into interior volume 169 of inner liner 160 through such elements
during step 770. Similarly, polyurethane elastomer 190 can also
limit or prevent leakage of polyurethane foam 192 into machinery
compartment 151 at step 770.
[0039] During step 770, the polyurethane foam 192 can also adhere
to polyurethane elastomer 190 within cavity 170. In turn,
polyurethane elastomer 190 can adhere to inner liner 160, outer
case 150 or other components of refrigerator appliance 100. In such
a manner, polyurethane elastomer 190 and polyurethane foam 192 can
enhance a structural rigidity of housing 120 during step 770. In
particular, after step 770, polyurethane foam 192 can hinder
racking or other movement of housing 120 by extending between and
adhering to outer case 150, inner liner 160, rear panel 180 and
polyurethane elastomer 190.
[0040] 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.
* * * * *