US20090113906A1

US20090113906A1 - Air Damper Units With Improved Air Flow

Info

Publication number: US20090113906A1
Application number: US11/934,460
Authority: US
Inventors: Tracy Talley
Original assignee: Emerson Electric Co
Current assignee: Emerson Electric Co
Priority date: 2007-11-02
Filing date: 2007-11-02
Publication date: 2009-05-07

Abstract

A sliding door air damper unit for a refrigerator includes a base plate having an aperture, a sliding door slidably mounted on the base plate for controlling air flow through the aperture, and a modular driving assembly for driving the sliding door. The modular driving assembly includes a housing defining an inner space, a cam device suspended from the housing and a motor mounted on the housing. The sliding door is driven by the cam device to move back and forth and can slide through a gap between the cam device and the base plate. The travel distance of the sliding door is increased and thus the aperture can be made larger to allow more air to flow through the aperture. The sliding door air damper unit allows a refrigerator compartment of the refrigerator to quickly reach a predetermined temperature setting.

Description

FIELD

The present disclosure relates generally to air damper units for refrigerators and more particularly to a sliding door air damper unit with improved air flow.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Known refrigerators typically include a freezer compartment and a refrigerator compartment separated by a partition wall. A compressor system of the refrigerator cools the air in the freezer compartment directly, whereas the refrigerator compartment is cooled by the cold air directed from the freezer compartment into the refrigerator compartment through an air passageway disposed in the partition wall. An air damper is generally mounted adjacent to the air passageway to cover and uncover the air passageway, thereby regulating the amount of air flow into the refrigerator compartment and, ultimately, the temperature of the refrigerator compartment.
The air damper may be controlled automatically or manually to cover and uncover the air passageway in response to a thermostat or a temperature sensor indicating whether or not the temperature of the refrigerator compartment has reached a predetermined temperature setting. When the air damper is in a fully-closed position, the cold air from the freezer compartment is completely blocked and no cooling is applied to the refrigerator compartment. When the air damper is in a fully open position, a maximum amount of cold air is allowed to enter the refrigerator compartment to reduce the temperature of the refrigerator compartment.
A first type of air dampers is a flapper door type. The flapper door air damper uses a flapper door and its pivoting action to cover and uncover the air passageway. The flapper door air damper has a disadvantage in that when ice is built up around the periphery of the flapper door, it is relatively difficult to break the ice by the pivoting action of the flapper door.
A second type of air dampers is a sliding door type. The sliding door air damper includes a sliding door which moves on a plane substantially parallel to the partition wall that defines the air passageway to cover and uncover the air passageway. The sliding door air damper is desirable in terms of its relative ease to break the ice by the sliding action of the sliding door when ice is built around the periphery of the sliding door. An issue with the sliding door air damper, however, is the limited air flow that is allowed to flow through the air damper when the air damper is in its fully-open position. In the typical sliding door air damper, the size of an aperture formed in the air damper that communicates with the air passageway of the refrigerator depends on the travel distance of the sliding door. The maximum travel distance of the sliding door is typically small and is approximately the distance between the driving mechanism and the sliding door. With a small aperture, the sliding door air damper does not allow a desired amount of cold air to flow into the refrigerator compartment quickly to reach a desired temperature setting.

SUMMARY

Several embodiments of the present disclosure provide for sliding door type air dampers with improved air flow. In one form, the air damper unit for controlling air flow through an air passageway of a partition wall of a refrigerator includes a sliding door, a support and a cam device. The sliding door is slidably movable on a plane substantially parallel to the partition wall to cover and uncover the aperture. The cam device drives the sliding door to move back and forth and is moveably mounted to the support. The cam device and the sliding door are movable relative to one another to a position such that a portion of the door overlaps a portion of the cam device in a direction substantially perpendicular to the partition wall. In particular, a gap can be formed between the cam device and the partition wall, and the sliding door is movable through the gap.
In another form, an air damper unit for controlling air flow through an air passageway of a partition wall of a refrigerator includes a sliding door, a cam device, and a unidirectional motor for driving the cam device. The sliding door is slidably movable on a plane substantially parallel to the partition wall. The sliding door has a follower slot. The cam device includes a rod received in the follower slot. Rotation of the cam device moves the rod that slidably moves the sliding door between a position covering the air passageway and a position uncovering the air passageway.
In yet another form, a modular driving assembly for an air damper unit having a sliding door includes a cam device for driving the sliding door back and forth, a motor for driving the cam device and a housing. The housing defines an inner space and includes a wall. The cam device is received in the inner space and suspended from the wall.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

FIG. 1 is a perspective view of an exemplary refrigerator including an air damper unit constructed in accordance with the teachings of the present disclosure;

FIG. 2 is an exploded view of an exemplary air damper unit constructed in accordance with a first embodiment of the present disclosure;

FIG. 3 is a cross-sectional view of an exemplary air damper unit constructed in accordance with a first embodiment of the present disclosure, taken along a longitudinal direction thereof;

FIG. 4 is a schematic plan view of an exemplary air damper unit of a first embodiment of the present disclosure, showing the air damper in a fully opened position, wherein some components are removed for clarity;

FIG. 5 is a schematic plan view of the air damper unit of FIG. 4, showing the air damper in a fully closed position;

FIGS. 6 a through 6 g are views illustrating sequential movement of a cam device relative to a follower slot;

FIG. 7 is a schematic plan view of an exemplary air damper unit of a second embodiment of the present disclosure, showing the air damper in a fully closed position;

FIG. 8 is a schematic plan view of an exemplary air damper unit of a third embodiment of the present disclosure, showing the air damper in a fully closed position; and

FIG. 9 is a schematic plan view of an exemplary sliding door of a fourth embodiment of the present disclosure.

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
Referring to FIG. 1, a refrigerator is illustrated and generally indicated by reference numeral 10. The refrigerator 10 includes a block-shaped cabinet 12, a partition wall 14, a freezer compartment 16 and a refrigerator compartment 18 separated by the partition wall 14. The freezer compartment 16 is cooled directly by a compressor unit of the refrigerator 10. The refrigerator compartment 18 is cooled by the cold air flowing from the freezer compartment 16 through an air passageway 20 defined in the partition wall 14 to the refrigerator compartment 18.
Referring to FIGS. 2 through 4, an air damper unit constructed in accordance with a first embodiment of the present disclosure is illustrated and generally indicated by reference number 22. The air damper unit 22 is disposed in the refrigerator compartment 18 and on the partition wall 14. The air damper unit 22 includes a base plate, generally indicated 24, a sliding door 26 slidably mounted on the base plate 24, and a driving assembly 28 for driving the sliding door 26. The driving assembly 28 comprises a cam device, generally indicated 30, a switch device, generally indicated 32, a support housing 34, and a motor assembly 36 including a motor body, generally indicated 38, and a motor cover, generally indicated 40.
The base plate 24 is mounted on the partition wall 14 of the refrigerator 10 and has an aperture 42 for communicating with the air passageway 20 of the partition wall 14. The sliding door 26 moves on a plane substantially parallel to the base plate 24 and the partition wall 14 to cover and uncover the aperture 42 of the base plate 24 and hence the air passageway 20 of the partition wall 14. The base plate 24 has a first side 21 and a second side 23. A plurality of guiding rails 44 are provided adjacent to the first side 21 along two opposing edges that define the aperture 42. The guiding rails 44 guide the sliding door 26 to move on the base plate 24 in a sliding direction X. A plurality of mounting members 46 are provided adjacent to the second side 23 and extend in a direction perpendicular to the base plate 24 for positioning and mounting the support housing 34 on the base plate 24. The mounting members 46 each include a pair of locking legs 48 to be inserted into a plurality of sockets 50 provided at the support housing 34. The support housing 34 is mounted on the base plate 24 through a snap action of the locking legs 48. In one exemplary embodiment, the base plate 24 and the support housing 34 are each made of plastic and integrally formed.
The cam device 30 is received within the support housing 34 and suspended from an upper wall 49 of the support housing 34. A gap G (shown in FIG. 3) is formed between the cam device 30 and the base plate 24 so that the sliding door 26 can freely slide through the gap G toward the second side 23 of the base plate 24 without being obstructed by the cam device 30.
The motor assembly 36 is mounted on the upper wall 49 of the support housing 34. The motor assembly 36 includes a motor 51 and an output shaft 52 extending through an opening 54 of the support housing 34 for engaging a mating portion 56 of the cam device 30 so that the motor 51 drives the cam device 30 to rotate when the motor 51 rotates.
The switch device 32 is received inside the support housing 34 adjacent to the cam device 30. The switch device 32 includes a pair of spring arms 58 and a plurality of connectors 60 for connecting to external electric circuits. The switch device 32 is closed when the spring arms 58 are biased against and in contact with each other and is opened when the spring arms 58 return to their normally separated position. One of the spring arms 58 includes a lateral portion 64 extending laterally for contacting the cam device 30.
The cam device 30 includes the mating portion 56, a first cam surface 74, a second cam surface 76, and an extension arm 68 extending radially from the mating portion 56. The first cam surface 74 has a radius R1 larger than a radius R2 of the second cam surface 76. The extension arm 68 includes a rod 70 suspended from the extension arm 68 and inserted in a follower slot 72 of the sliding door 26.
The follower slot 72 can be configured to have different shapes, depending on specific applications. In the embodiment of FIGS. 2 through 5, the follower slot 72 has approximately an S-shaped configuration. FIG. 7 shows a straight line-shaped follower slot 82 oriented to define an angle relative to an adjacent edge of the sliding door 83. FIG. 8 shows a follower slot 84 having a straight line configuration oriented to be parallel to an adjacent edge of the sliding door 85. FIG. 9 shows a follower slot 114 having two straight portions 116 and 120 and a curved portion 118 connecting the two straight portions 116 and 120.
Referring to FIGS. 4, 5 and 6 a through 6 g, the follower slot 72 includes two parallel segments 61 and 65 and one angled segment 63 connecting the two parallel segments 61 and 65. The three segments 61, 63 and 65 define a first position 77, a second position 78, a third position 79 and a fourth position 80. The follower slot 72 is so configured that when the sliding door air damper 22 is in its fully open position, the rod 70 is at the second position 78 (FIG. 6 a). When the cam device 30 rotates clockwise, the rod 70 moves from the second position 78 (FIG. 6 a), through the third position 79 (FIG. 6 b) to the fourth position 80 (FIG. 6 c) at one of the extremities of the follower slot 72. As the rod 70 moves, the rod 70 pushes the sliding door 26 to move toward the first side 21 of the base plate 24 to gradually cover the aperture 42. When the cam device 30 rotates 180°, the rod 70 moves from the second position 78 (FIG. 6 a) to the third position 79 (FIG. 6 b) to the fourth position 80 (FIG. 6 c) and back to the third position 79 (FIG. 6 d). At this point, the sliding door 26 fully covers the aperture 42 of the base plate 24 as shown in FIG. 5.
As the cam device 30 continues to rotate clockwise, the rod 70 of the cam device 30 continues to move from the third position 79 (FIG. 6 d) toward the second position 78 (FIG. 6 e) to the first position 77 (FIG. 6 f) and back to the second position 78 (FIG. 6 g). The movement of the rod 70 causes the sliding door 26 to move toward the second side 23 of the base plate 24 to gradually uncover the aperture 42. When the cam device 30 rotates 360°, the rod 70 reaches the second position (FIG. 6 g) and pushes the sliding door 26 to the fully open position. The continuous rotation of the motor 51 and the cam device 30 causes the sliding door 26 to move back and forth in the sliding direction X to cover and uncover the aperture 42 of the base plate 24.
The switch device 32 is provided adjacent to the cam device 30 for providing feedback to an external controller system. The spring arms 58 and the lateral portion 64 are configured so that when the lateral portion 64 faces the second cam surface 76, the spring arms 58 are not biased to contact each other. When the lateral portion 64 faces the first cam surface 74 which has a larger radius, the first cam surface 74 pushes the lateral portion 64 and the spring arms to contact each other to close the switch device 32.
The first cam surface 74 and the second cam surface 76 are shown to have an arc of 180°. Therefore, the switch device 32 remains closed when the cam device 30 rotates 180°. The switch device 32 is opened and remains open when the cam device 30 continues to rotate another 180°. The first cam surface 74 and the second cam surface 76 can be properly designed so that the switch device 32 is in contact with the first cam surface 74 when the air damper unit 22 gradually covers or uncovers the aperture 42. Therefore, the closed switch 32 which transmits a signal to the controller system can indicate the sliding direction of the sliding door 26.
Alternatively, while not shown in the figures, the cam device 30 can have a plurality of first peripheral surfaces having a larger radius and a plurality of second peripheral surfaces having a smaller radius. The first and the second peripheral surfaces are arranged alternately. By closing and opening the switch device in smaller increments, the position of the sliding door 26, and thus the location of the rod 70, can be more precisely determined.
FIGS. 7 and 8 show an air damper unit 90 and 100, respectively, having a construction similar to that shown in FIGS. 2 to 5. The air damper units 90 and 100 are different from the air damper unit 22 only in the shape and orientation of the follower slots 82 and 84. Accordingly, the detailed description thereof is omitted herein for clarity.
FIG. 9 shows a sliding door 110 that has a substantially square shape with a curved portion 112 at one edge. The sliding door 110 has a slot 114 composed of two straight portions 116 and 120 and one curved portion 118 between the two straight portions 116 and 120. The operation of the sliding door 110 in this embodiment is similar to what has been described in connection with air damper units 22, 90 and 100. Accordingly, the detailed description thereof is omitted herein for clarity.
Because the cam device 30 is suspended from the support housing 34, the sliding door 26 can freely slide through the gap G between the cam device 30 and the base plate 24 and reach an area close to the second side 23 of the base plate 24. The travel distance of the sliding door 26 is significantly increased. As a result, the aperture 42 of the base plate 24 can be made larger than that of the typical sliding door air damper unit to allow more cold air to pass through in the fully-open position. In the typical sliding door type air damper unit, the driving mechanism is mounted on the base plate and the travel distance is limited to the distance between the driving mechanism and an edge of the sliding door. In the air damper unit of the present disclosure, however, the movement of the sliding door is not restricted by the cam device 30 (e.g., the cam device and the sliding door are movable relative to one another to a position such that a portion of the door overlaps a portion of the cam device in a direction substantially perpendicular to the partition wall). Therefore, the increased travel distance of the sliding door 26 leads to an enlarged aperture 42 of the base plate 24. The air damper unit 22 of the present disclosure allows more cold air to flow from the freezer compartment 16 to the refrigerator compartment 18, thereby allowing the refrigerator compartment 18 to quickly reach the predetermined temperature settings.
Apart from the increased air flow, the sliding door air damper unit has an advantage of easy assembly. In the typical sliding door air damper unit, the driving mechanism may include a motor, a cam and reduction gears, which are individually mounted to the base plate. In contrast, the present air damper unit includes a modular driving assembly in which the motor 51 and the cam device 30 are mounted to the support housing 34 as a unit. The whole assembly can be easily mounted to the base plate 24 through the snap action of the mounting members 46 of the base plate 24 and the sockets 50 of the support housing 34. Therefore, the assembly time is significantly reduced.
While not shown in the Figures, it should be understood and appreciated that the air damper unit may include a printed circuit board on the base plate 24, which includes a position sensor for detecting the position of the sliding door 26, or heating resistors for defrosting the building ice around the periphery of the sliding door 26. Optionally, a fan may be mounted to the base plate 24 and disposed inside the aperture 42 to help draw the cold air from the freezer compartment 16 into the refrigerator compartment 18 to improve air circulation.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

Claims

1. An air damper unit for controlling air flow through an air passageway of a partition wall of a refrigerator, comprising:

a sliding door slidably movable in a plane substantially parallel to the partition wall to substantially cover and uncover the air passageway;

a support; and

a cam device for driving the sliding door to move back and forth, the cam device moveably mounted to the support,

wherein the cam device and the sliding door are movable relative to one another to a position such that a portion of the door overlaps a portion of the cam device in a direction substantially perpendicular to the partition wall.

2. The air damper unit of claim 1 wherein a gap is formed between the cam device and the partition wall, and the sliding door is movable through the gap.

3. The air damper unit of claim 1, further comprising one of a unidirectional motor or a bidirectional motor for driving the cam device.

4. The air damper unit of claim 3 wherein the cam device is driven by the motor through an angle of rotation of 360°.

5. The air damper unit of claim 3, wherein the motor is mounted on the support.

6. The air damper unit of claim 3, wherein the cam device, the motor and the support form a modular unit.

7. The air damper unit of claim 1, wherein the support includes a support housing defining an inner space, the cam device received in the inner space.

8. The air damper unit of claim 7, wherein a motor is mounted on and outside the support housing.

9. The air damper unit of claim 8, wherein the motor drivingly engages the cam device through an opening of the support housing.

10. The air damper unit of claim 7, further comprising a base plate to be mounted to the partition wall of the refrigerator, the base plate having an aperture communicating with the air passageway, the support housing mounted to the base plate.

11. The air damper unit of claim 10, wherein the support housing and the base plate include mating features for connecting the support housing and the base plate.

12. The air damper unit of claim 1, further comprising a follower slot provided on the sliding door for engaging the cam device.

13. The air damper unit of claim 12, wherein the follower slot approximately defines a shape selected from a group consisting of an S-shape, a straight line, and a curved shape.

14. The air damper unit of claim 1, further comprising a switch device provided adjacent to the cam device for providing feedback of movement of the cam device.

15. An air damper unit for controlling air flow through an air passageway of a partition wall of a refrigerator, comprising:

a sliding door slidably movable on a plane substantially parallel to the partition wall, the sliding door having a follower slot;

a cam device including a rod received in the follower slot, whereby rotation of the cam device moves the rod that slidably moves the sliding door between a position substantially covering the air passageway and a position substantially uncovering the air passageway; and

a motor for driving the cam device.

16. The air damper unit of claim 15, further comprising a base plate having an aperture communicating with the air passageway, a housing mounted to the base plate, wherein the housing defines an inner space and the cam device is suspended in the inner space.

17. The air damper unit of claim 16, wherein the motor includes an output shaft extending through an opening of the housing for engaging the cam device.

18. The air damper unit of claim 15, wherein the motor is one of a unidirectional motor or a bidirectional motor.

19. The air damper unit of claim 18 wherein the cam device is driven by the motor through an angle of rotation of 360°.

20. A modular driving assembly for an air damper unit having a sliding door, comprising:

a cam device for driving the sliding door back and forth;

a motor for driving the cam device; and

a housing defining an inner space and having a wall, the cam device received in the inner space and suspended from the wall.

21. The driving assembly of claim 20, wherein the motor is mounted on the wall and outside the housing; the motor includes an output shaft extending through an opening of the wall; and the motor drivingly engages the cam device through the opening of the wall.

22. The driving assembly of claim 20, wherein the modular driving assembly is mounted to an adjacent component by connecting the housing to the adjacent component.

23. An air damper unit of the type comprising a motor driven cam that rotates about an axis and engages a door to drive the door back and forth in a direction perpendicular to the axis to open and close an aperture, the air damper unit comprising:

a support housing comprising a first wall a least partially lying in a plane generally perpendicular to the axis;

a planar base generally parallel to and offset from the first wall, the aperture extending through the base;

the support housing and the base combining to define an interior space of the unit to which an inner surface of the first wall and an inner surface of the base are adjacent;

the door disposed on the inner surface of the base and cooperable with the base for sliding movement thereon such that in a first position the door covers the aperture and in a second position the door uncovers the aperture; and wherein

the cam is mounted on the inner surface of the first wall such that it is disposed within the interior space and spaced apart from the door in a direction along the axis so as to create a gap.

24. The air damper unit of claim 23 wherein the door travels through the gap as it moves from one of the first position or the second position to the other of the first position or the second position.

25. The air damper unit of claim 24 wherein the motor is one of a unidirectional motor or a bidirectional motor; and

wherein the cam is driven by the motor through an angle of rotation of 360°.