Note: Descriptions are shown in the official language in which they were submitted.
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REFRIGERATOR CRISPER AIR FLOW CONTROL ASSEMBLY
Field of the Invention
The present invention relates to a household refrigerator crisper drawer
assembly wherein there is an arrangement for controlling and adjusting the
level of humidity within the crisper drawers where the assembly of the air
flow
control handle in the crisper cover is simplified.
Background of the Invention
Household refrigerators typically include combination refrigerators, that
is, a refrigerator including a freezer compartment and a fresh food
compartment, with one of the two compartments located above the other and
both of which are cooled via circulating air from the two compartments over an
evaporator employing a fan to accomplish the circulation.
Combination refrigerators, including an evaporator and a fan for
circulating air from the freezer and fresh food compartments over the
evaporator are well known. In the operation of such refrigerators, a major
portion of the refrigerated air from the evaporator is directed into the
freezer
compartment while a smaller portion is directed into the fresh food
compartment. When cold air from the freezer compartment is used to cool the
fresh food compartment, such air, because of its relative dryness, should not
directly contact the fresh foods such as fruits and vegetables as they will
become dried out and lose their freshness. The fresh foods are desirably
isolated from the desicating effect of the cooler air so that they may be kept
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cool, yet moist. Sealed compartments or drawers have been used for this
purpose. It is desirable, however, that such drawers have the humidity inside
the drawer adjustable or controllable by the user to provide the desired
humidity, depending on the type of food load. The food load is the source of
moisture inside the drawer. Certain types of food have more moisture and will
raise the humidity inside the drawer as compared to other types of food.
Moreover, certain types of food, such as green vegetables, should best be
stored at a high relative humidity, while others such as fruit should not.
Also,
different degrees of humidity are desirable according to the amount of food
placed in the drawer. Small loads tend to dry out more so than larger loads.
Various arrangements in the prior art have been used to adjust drawer
ventilation and therefore, the humidity inside the drawer.
One arrangement for adjusting the drawer ventilation and therefore
controlling the humidity within the drawer is disclosed in U.S. Pat. No.
4,013,434 issued March 22, 1977 to Kronenberger et al. In this arrangement
the drawers have guides along the side of the drawer cover that have vents
which are covered by a rotatable damper having a plurality of positions and
rotation thereof controls the ventilation of the drawers.
U.S. Pat. No. 4,557,118 issued December 10, 1985 to Pink et al has an
arrangement wherein there is a passageway all along the rear of the drawer
which is unsealed and therefore continuously open to allow air to enter into
the drawer through that opening. The front of the cover has a passageway
with a slide gate for the user to vary the amount of ventilation of the
drawer.
The assembly requires a slide gate to be held on the rigid frame while a
casing strip is mounted to the frame. The casing strip has a slotted opening
through which the neck of a slide knob must then be inserted for assembly
with the slide gate. This assembly procedure is cumbersome and somewhat
labor intensive.
By this invention there is provided a household refrigerator crisper
drawer assembly that provides a slide gate or shutter for controlling air flow
into the crisper drawer that does not require extraordinary assembly of parts
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through the casing strip or trim cover mounted to the crisper frame and the
extra cost associated therewith. Further the present invention provides a
crisper drawer assembly that permits only for indirect air flow into the
crisper
drawer through the assembly.
Summanr Of The Invention
The present invention relates to a crisper drawer assembly for
providing a controlled humidity storage region in a refrigerator fresh food
compartment. The assembly has a crisper frame adapted for mounting
horizontally near the bottom of said refrigerator compartment. The frame is
adapted to carry the drawer. The frame has a front horizontal support
member that has a front wall with a forward projecting lip. The lip has a
vertically extending forward edge wall portion. A trim cover is secured
between the front wall and the forward edge wall portion to define an air flow
cavity. At least one first port extends along at least one of the lip, forward
edge wall portion and both to provide air flow communication between the air
flow cavity and the refrigerator fresh food compartment. At least one second
port extends along at least one of the front wall, lip and both to provide air
flow
communication between the air flow cavity and the drawer. A flow dividing
wall extends vertically from the lip between the first and second ports. The
flow dividing wall extends from the lip to contact the trim cover to define
separate and distinct forward and rearward channels within the cavity. The
flow dividing wall has at least one notch adjacent the trim cover to redirect
air
flow therethrough between the forward and rearward channels. The provision
of the flow dividing wall creates a redirection in the air flow so that air
does not
flow directly through the cavity between the ports. This provides for better
humidity control within the drawer.
A shutter is provided that is slidable along the forward channel to
selectively open and close the first port to control air flow into the drawer.
In
one embodiment the shutter is formed as one piece and has an actuator arm
that extends through an opening in the forward edge wall portion below the
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trim cover. The trim cover provides an upper boundary for this opening when
the trim cover is secured to the front wall and the forward edge wall portion.
This arrangement has the advantage of not requiring any slots to be cut in the
trim cover and not requiring an additional assembly step of securing a control
knob to the shutter through a slot cut out into the trim cover.
In one embodiment the forward edge portion has a series of notches
spaced along the opening in the forward edge portion for receiving the
actuator arm. These notches provide for graduated controlled sliding of the
shutter by the user.
In accordance with the present invention there is provided a crisper
drawer assembly for providing a controlled humidity storage region in a
refrigerator fresh food compartment. The assembly comprises a drawer
having a bottom wall, side walls, a back wall, and a front wall, and the said
side walls each having an outwardly extending flange. The assembly
comprises a crisper frame adapted for mounting horizontally near the bottom
of said refrigerator compartment. The frame has underside parallel slide
channels for receiving the flanges wherein the drawer is slidably engageable
in the slide channels to a closed position underneath the frame. The frame
has a front horizontal support member having a front wall with a forward
projecting lip. The lip has a vertically extending forward edge wall portion.
The assembly has a trim cover securable between the front wall and the
forward edge wall portion to define an air flow cavity between the trim cover,
front wall, lip and forward edge wall portion. At least one first port extends
along at least one of the lip, forward edge wall portion and both to provide
air
flow communication between the air flow cavity and the refrigerator fresh food
compartment. At least one second port extends along at least one of the front
wall, lip and both to provide air flow communication between the air flow
cavity
and the drawer. A flow dividing wall extends vertically from the lip between
the first and second ports. The flow dividing wall also extends from the lip
to
contact the trim cover to define separate and distinct forward and rearward
channels within the cavity. The flow dividing wall has at least one notch
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adjacent the trim cover to redirect air flow therethrough between the forward
and rearward channels. The assembly has a shutter slidable along the
forward channel to selectively open and close the first port to control air
flow
into the drawer.
Brief Description Of The Drawings
For a better understanding of the nature and objects of the present
invention reference may be had to the following detailed description when
taken in conjunction with the accompanying diagrammatic drawings wherein:
Figure 1 is a front perspective view of a refrigerator having a crisper
assembly;
Figure 2 is an exploded perspective view of the crisper frame and
cover seal;
Figure 3 is a side sectional view of the crisper assembly;
Figure 4 is a front sectional view of a portion of the crisper assembly;
Figure 5 is an enlarged sectional view of the sealing between the
crisper drawers and the crisper frame;
Figure 6 is an enlarged sectional view of showing the air flow into the
front of the crisper assembly;
Figure 7 is a sectional view showing the mounting of the crisper
assembly to the rear wall of the refrigerator;
Figure 8 is an enlarged sectional view showing the mounting of the
crisper assembly to one of the side walls of the refrigerator; and,
Figure 9 is a plan view of the crisper frame showing a shortened guide
rail for the middle support rail of the crisper frame.
Detailed Descriation Of The Invention
The present invention relates to a refrigerator crisper air flow control
handle and, in particular to the assembly of the air flow control handle in
the
crisper cover.
Referring to Figure 1 of the drawings, there is shown one embodiment
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of the present invention in the form of a household refrigerator 10, including
an upper freezer compartment 12 and a lower fresh food compartment 14
separated from the freezer compartment by an insulated mullion partition 16.
While the embodiment of the refrigerator illustrated is for a top mount
refrigerator, it should be understood that the invention is also applicable
for
bottom mount refrigerators where the freezer compartment is located below
the fresh food compartment. The respective compartments 12, 14 are also
separated from the outer cabinet walls 17 and the spaces between the
compartments and these walls are filled with thermal insulation (not shown). A
hinged door 18 permits access to the freezer compartment 12 and a hinged
door 20 permits access to the fresh food compartment 14.
As is common to refrigerators of this design, the compartments 12, 14
are maintained at the desired refrigerating temperatures by means of a single
evaporator (not shown) which operates at a below freezing temperature. Air
cooled by the evaporator is directed into the two compartments 12, 14 by a
forced air circulating system. Most of the air passes into the freezer
compartment 12 while a portion of the cooled air is directed by air duct means
22 located either at the rear of the compartments, or in the mullion 16
separating the compartments, downwardly into the fresh food compartment
14.
In household refrigerators 10, it is desirable to provide a crisper drawer
and in the case of the present invention two side by side crisper drawers 24
in
the fresh food compartment 14 in which fresh fruits and vegetables may be
kept. As shown in Figure 1, the crisper drawers 24 are positioned side by
side and are of the same size. In alternative embodiments, the crisper
drawers 24 may have different widths. In the illustrated embodiment of the
present invention both crisper drawers 24 are supported by a rigid frame 26 in
such a manner that the crisper drawers 24 may slide in and out relative to the
rigid frame 26. As shown in Figures 1 and 7, the rigid frame 26 is attached at
its rear to spaced vertical slotted tracks 28 which are suitably secured to
the
back wall 30 of finer 32 of the fresh food compartment 14. As shown in
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Figures 1 and 8, the rigid frame 26 is supported at the front by means of
support members 34 that are secured to each of the side walls 36 of the fresh
food compartment 14 whereby the front portion of the rigid frame 26 rests on
the support members 34.
Referring to Figures 3 and 4, the crisper drawers 24 are supported by
the rigid frame 26 and have a back wall 38, a front wall 40, side walls 42,
bottom wall 44 (Figure 3) and an open top having a periphery 46. Along the
periphery 46 of the open top at the junction of the side walls 42 there are
outwardly and downwardly depending flanges 48 and 50 that generally extend
along the length of the top portion of the side walls 42. On the front wall 40
of
each of the crisper drawers 24 there is a recess 52 with an outwardly
depending flange 54 to allow the user to grip the crisper drawer 24 for moving
it in and out relative to the rigid frame 26.
The rigid unitary frame 26 is molded from plastic and extends nearly
the entire width of the fresh food compartment 14. As shown in Figures 3 and
6, the molded plastic unitary frame 26 has the front horizontal support
member 56 that has a downwardly depending sealing flange portion 58
extending along the front horizontal support member 56 for sealing
engagement with the front wall 40 of the crisper drawers 24 to restrict air
flow
past the flange 58 and into the crisper drawer 24.
Referring now to Figures 3 and 5, the unitary frame 26 is molded to
have a rear horizontal support member 60 that has a downwardly depending
solid rear wall 62 and one downwardly depending flexible wall portion 64
spaced inwardly of the solid rear wall 62. The flexible wall portion 64 seats
against the back wall 38 of the crisper drawers 24 when the drawer is closed
to restrict air flow past the flexible wall portion 64 and into the crisper
drawer
24. The flexible wall 64 is thinning converging flange wall 64 that abuts
against a rear flange 39 that extends outwardly from the back wall 38 adjacent
open periphery 46.
In Figures 2, 3 and 4, the molded unitary frame 26 is shown to have
two side horizontal support members 66 and a intermediate horizontal support
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member 68. The two side horizontal support members 66 and the
intermediate horizontal support member 68 each span the distance between
the front and rear horizontal support members 56, 60 and each have a
downwardly depending slide carrier 70 having a horizontal channel 72 to
receive the crisper drawer flanges 48, 50 and support the crisper drawers 24
thereon. The intermediate member 68 has a central or intermediate
downwardly depending slide carrier 74 that has horizontal channels 76 on
opposing sides of the carrier 74. Channels 72 and 76 are underside parallel
slide channels.
The crisper assembly 23 has a cover 78 for the crisper drawer
assembly is a removable cover which is made from tempered glass or plastic
and is supported by the rigid frame 26. This removable cover 78 also acts as
a shelf in the fresh food compartment 14 so that items to be refrigerated may
be placed on top of the cover 78.
The rigid frame 26 has integrally formed from the rear horizontal
support member 60 three spaced apart post projections 80 which engage the
slots 184 in the tracks 28 (Figure 7) to thereby retain the frame 26 and the
crisper drawers 24 with the rear of the fresh food compartment 14. The rear
horizontal member 60 has footings 82 for spacing the rear horizontal member
60 from the vertical tracks 28. One post 80 extends from each the footings 82
into slotted openings in the vertical tracks 28. The posts 80 are rectangular
in
cross-section. Alternatively, the posts 80 may be of another shape such as a
square shape.
The rigid frame 26 is illustrated in Figures 6, 7 and 8 to be supported at
the front by means of support members 34 that are secured to the side walls
36 of the fresh food compartment 14. The front horizontal support member 56
of the rigid frame 26 rests on the support members 34. The front horizontal
support member 56 has an elongated slotted aperture 84 for receiving a
reinforcing bar 86 that extends along the length of the front horizontal
support
member 56. The elongated slotted aperture 84 of the front horizontal member
56 has two side walls 88 with hook shaped locking tabs 90 (Figure 6)
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extending into the slotted aperture 84 for holding or grasping the reinforcing
support bar 86 when snap fitted into the slotted aperture 84 past tabs 90. End
portions 92 (Figure 8) of the reinforcing bar 86 are supported or rest on the
protruding side members 34. The front horizontal support member 56 has
rounded walls 94 located below the slotted aperture 84 at the end portions 92
of the front horizontal member 56 for receiving the protruding support
members 34 to hold the unitary rigid frame 26 within the fresh food
compartment 14 thereby preventing forward and rearward movement of the
crisper assembly 23 relative to the fresh food compartment 14. Alternatively,
walls 94 may be square or rectangular in shape.
The crisper assembly 23 has a feature that facilitates the removal of
the crisper drawers 24, and in particular, the crisper drawer 24 positioned in
the fresh food compartment 14 closest to the door 20. This feature relates to
the slide carriers 70 for supporting the crisper drawers 24. As shown in
Figure 9, the two side horizontal support members 66 and the intermediate
horizontal support member 68 each span the distance between the front and
rear horizontal support members 56, 60. The two side horizontal support
members 66 each have a downwardly depending slide carrier 70 having a
side end horizontal channel 72 extending between the front and rear support
members 56, 60 to receive the crisper drawer flanges 48, 50. The
intermediate slide carrier 68 has a side carrier 74 with opposing center
located horizontal channels 76 that also receive the crisper drawer flanges.
The opposing center located horizontal channels 70 extend from the rear
horizontal support member 60 and terminate a first predetermined distance 98
from the front horizontal support member 56. This predetermined distance 98
is chosen to permit the drawer 24 closest to the door 20 to be pulled forward
and at the same time rotated towards the center of the fresh food
compartment 14 for removal from the slide carriers 70, 74 when the door
cannot be opened beyond a 90 degree angle.
To prevent the crisper drawers 23 from being inadvertently pulled from
the frame 26, the side end horizontal channels 72 and the opposing channels
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74 each include a downwardly depending projection 102 (see Figures 2 and
3} spaced the same second predetermined distance 104 from the rear support
member 60. This second predetermined distance 104 is slightly more than
half way towards the front support member 56 from the rear support member
60. Each of the crisper drawers 24 carry upwardly extending stops 106 (see
Figures 3 and 4} located on the flange 48 adjacent the back wall 38 of the
crisper drawer 24. The stops 106 engage the depending projections 102 and
limit forward sliding of the crisper drawers 24 along the two side and
intermediate slide carriers 70, 74. The crisper drawers 24 can be removed
from the slide carriers 70, 74 by advancing the drawers 24 forward until the
stops 106 engages the depending projections 102 and then temporarily lifting
up the front of the drawer 24 and pulling the drawer 24 forward until the
stops
106 pass under the projections 102.
Each of the crisper drawers 24 in the crisper drawer assembly 23
provides a controlled humidity storage region in a refrigerator fresh food
compartment 14. Air flow into the closed drawers 24 is provided through the
front horizontal support member 56 of the rigid frame 26 as shown by arrows
111 in Figure 6. The front horizontal support member 56 has a front wall 108
that has a raised flange portion 110 and a forward horizontally projecting lip
112. The lip 112 has a vertically extending forward edge wall portion 114
provided with a hook shaped barb 116. Front sealing flange 58 depends
downwardly from the lip 112.
Referring to Figures 2 and 6, a plastic trim cover 118 is secure
between the front wall 108 and the forward edge wall portion 114. The trim
cover 118 has curved ends 120 that fasten or grasp the raised flange 110 of
the front wall portion 108 and the hook shaped barb 116 of the forward edge
wall portion 114. When the trim cover 118 is secured to the front horizontal
support member 56 there is defined an air flow cavity 122 between the trim
cover 118, front wall 108, lip 112, and forward edge wall portion 114.
The forward edge wall portion 114 has a plurality of spaced apart first
ports 124 cut out from the corner where the lip 112 and forward edge wall
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portion 114 meet to provide air flow communication between the air flow
cavity 122 and the refrigerator fresh food compartment 14. The front wall 108
has a plurality of spaced apart second ports 126 cut out from the corner
where the front wall 108 and lip 112 meet to provide air flow communication
between the air flow cavity 122 and the drawer 24.
A flow dividing wall 128 extends vertically into cavity 122 from the lip
112 between the first and second ports 124, 126. The flow dividing wall 128
extends from the lip 112 to contact the trim cover 118 to define separate and
distinct forward and rearward channels 130, 132 within the cavity 122. The
flow dividing wall 128 has a plurality of spaced apart notches 134 each
located adjacent the trim cover 118 to redirect air flow therethrough between
the forward and rearward channels 130, 132. This indirect air flow limits the
air flow between the fresh food compartment 14 and the drawer 24 to better
control humidity within the drawer 24.
A vertically extending single piece shutter 136 is slidable along the
forward channel 130 to selectively open and close the first ports 124 to
control
air flow into the drawer 24. The shutter 136 is formed as one piece having an
actuator arm 138 that extends through an opening 140 (see Figure 2) in the
forward edge wall portion 114 below the trim cover 118. The trim cover 118
provides an upper boundary for the opening 140 in the forward edge portion
114 when the trim cover 118 is secured to the front wall 108 and the forward
edge wall portion 114. This permits for ease of assembly whereby the shutter
136 can simply be placed in the forward channel 130 with the actuator 138
extending forward of the assembly. Next the trim cover 118 is secured on the
front horizontal support member 56. The trim cover 118 does not require a
slot to be cut out therein for the actuator 138. Also, the actuator 138 is
formed
of a single piece eliminating the need to glue on the actuator to the shutter
after the trim cover 118 is secured.
The forward edge wall portion 114 has a series of notches 144 (see
Figure 2) spaced along the opening 140 for receiving the actuator arm 138.
The shutter 136 extends along the forward channel 130 vertically adjacent the
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flow dividing wall 128. Shutter 136 is movable horizontally along the forward
channel 130 by a user moving actuator arm 138. The horizontal displacement
of the shutter is limited by the side walls 150 of opening 140 engaging
actuator 138. The shutter 136 has an angled top portion 146 adapted to close
the top of the first port openings 124.
While the invention has been described in terms of very specific
embodiments, those skilled in the art will recognize that the invention can be
practiced with modification within the spirit and scope of the claims.
