Patent Application
20180051409
The present subject matter relates generally to fan assemblies for appliances, such as dryer appliances.
Dryer appliances generally include a cabinet with a drum rotatably mounted therein. A motor can selectively rotate the drum during operation of the dryer appliance, e.g., to tumble articles located within a chamber defined by the drum. Dryer appliances also generally include a heater assembly that passes heated air through the chamber of the drum in order to dry moisture laden articles disposed within the chamber.
To circulate heated air, certain dryer appliances include a fan assembly positioned within a housing. During operation of the dryer appliance, an impeller of the fan assembly urges a flow of heated air into the chamber of the drum. Such heated air absorbs moisture from articles disposed within the chamber. The impeller also urges moisture laden air out of the chamber through a vent. The vent can be connected to household ductwork that directs the moisture laden air outdoors.
Performance of a dryer appliance can be affected by the flow of heated air. For example, dryer appliance performance can be improved by generating a large volume of heated air. Conversely, dryer appliance performance can be negatively affected if the heating assembly generates a low volume of heated air.
To improve dryer performance, a size of the impeller can be increased. However, space with a dryer appliance is generally limited or constrained. Thus, increasing a size of the impeller can be difficult. To improve dryer performance, certain dryer appliances include a second motor configured to rotate the impeller. However, motors can be expensive, and adding the second motor to the dryer appliance can increase the cost of the dryer appliance.
Accordingly, a dryer appliance with features for improving air flow through the dryer appliance would be useful. In particular, a dryer appliance with features for improving air flow through the dryer appliance without requiring a relatively large impeller or adding a second motor to the dryer appliance would be useful.
The present subject matter provides a fan assembly for a dryer appliance. The fan assembly includes an inlet duct that fluidly couples a chamber of the dryer appliance to a fan inlet. The inlet duct includes one or more guide vanes that are configured to direct the air in a manner that improves the pressure rise across the fan, thereby improving appliance performance. For example, the guide vanes may be positioned and oriented to generate a negative pre-swirl of the flow of air, such that the flow of air enters the fan inlet rotating in a direction opposite the direction of rotation of an impeller. Additionally, or alternatively, one or more guide vanes may be positioned and oriented to generate a laminar flow of otherwise turbulent air from the chamber of the dryer appliance. 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.
In a first exemplary embodiment, a dryer appliance is provided. The dryer appliance defines a vertical direction. The dryer appliance includes a cabinet defining a vent; a drum rotatably mounted within the cabinet, the drum defining a chamber for receipt of articles for drying; a motor; and a fan assembly defining an axial direction, a radial direction, and a circumferential direction. The fan assembly includes an impeller, the impeller being in mechanical communication with the motor and rotatable about the axial direction to urge a flow of air from the chamber of the drum to the vent of the cabinet. An inlet duct extends between and fluidly couples the chamber and a fan inlet. A guide vane is positioned within the inlet duct and oriented for directing the flow of air within the inlet duct, the guide vane defining an upstream end proximate the chamber and a downstream end proximate the fan inlet, the downstream end of the guide vane defining a tangent line. An exhaust duct extends between and fluidly couples a fan outlet and the vent of the cabinet.
In a second exemplary embodiment, a fan assembly for urging a flow of air from a chamber of a dryer appliance is provided. The dryer appliance defines a vertical direction, a lateral direction, and a transverse direction. The fan assembly includes an impeller being rotatable about an axis of rotation in a direction of rotation, the axis of rotation being substantially parallel to the transverse direction. An inlet duct extends between and fluidly couples the chamber and a fan inlet, the inlet duct being defined by a first side wall and a second side wall separated along the transverse direction and a top wall and a bottom wall separated along the vertical direction. A guide vane extends between the first side wall and the second side wall of the inlet duct, the guide vane defining an upstream end proximate the chamber and a downstream end proximate the fan inlet, the downstream end of the guide vane defining a tangent line that substantially aligns with a primary direction of the flow of air.
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.
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.
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.
As used herein, the term “article” may refer to but need not be limited to fabrics, textiles, garments (or clothing), and linens. Furthermore, the term “load” or “laundry load” refers to the combination of articles that may be washed together in a washing machine or dried together in a laundry dryer (i.e., a clothes dryer) and may include a mixture of different or similar articles of different or similar types and kinds of fabrics, textiles, garments and linens within a particular laundering process.
Dryer appliance 10 generally defines a vertical direction V, a lateral direction L, and a transverse direction T, which are mutually perpendicular with one another, such that an orthogonal coordinate system is generally defined. Dryer appliance 10 includes a cabinet 12 having a front panel 14 and a rear panel 16 spaced apart from each other along the transverse direction T. In addition, cabinet 12 includes a pair of side panels 18 and 20 spaced apart from each other by front and rear panels 14 and 16 along the lateral direction L. A bottom panel 22 and a top cover 24 are also spaced apart along the vertical direction V. Within cabinet 12 is a drum or container 26 mounted for rotation about an axis that is substantially parallel with the transverse direction T. Drum 26 is generally cylindrical and defines a chamber 27 for receipt of damp articles.
Drum 26 also defines an opening 29 for permitting access to the chamber 27 of drum 26. Opening 29 of drum 26, e.g., permits loading and unloading of clothing articles and other fabrics from chamber 27 of drum 26. A door 33 is rotatably mounted at opening 29 and selectively hinders access to chamber 27 of drum 26 through opening 29.
Drum 26 includes a rear wall 25 rotatably supported within cabinet 12 by a suitable fixed bearing. Rear wall 25 can be fixed or can be rotatable. A motor 28 rotates the drum 26 about the transverse direction T through a pulley 30 and a belt 31. Motor 28 is also in mechanical communication with a fan or air handler 42 such that motor 28 rotates an impeller 43, e.g., a centrifugal impeller, of air handler 42. Air handler 42 is configured for drawing air through chamber 27 of drum 26, e.g., in order to dry articles located therein as discussed in greater detail below. In alternative exemplary embodiments, dryer appliance 10 may include an additional motor (not shown) for rotating impeller 43 of air handler 42 independently of drum 26.
Drum 26 is configured to receive heated air that has been heated by a heater assembly 34, e.g., in order to dry damp articles disposed within chamber 27 of drum 26. Heater assembly 34 includes a combustion chamber 36. As discussed above, during operation of dryer appliance 10, motor 28 rotates drum 26 and impeller 43 of air handler 42 such that air handler 42 draws air through chamber 27 of drum 26 when motor 28 rotates impeller 43. In particular, ambient air, shown with arrow Aa, enters combustion chamber 36 via an inlet 38 due to air handler 42 urging such ambient air Aa into inlet 38. Such ambient air Aa is heated within combustion chamber 36 and exits combustion chamber 36 as heated air, shown with arrow Ah. Air handler 42 draws such heated air Ah through a back duct 40 to drum 26. The heated air Ah enters drum 26 through a plurality of holes 32 defined in rear wall 25 of drum 26.
Within chamber 27, the heated air Ah can accumulate moisture, e.g., from damp articles disposed within chamber 27. In turn, air handler 42 draws moisture laden air, shown as arrow Am, through a screen filter 44 which traps lint particles. Such moisture laden air Am then enters a front duct 46 and is passed through air handler 42 to an exhaust duct 48. From exhaust duct 48, such moisture laden air Am passes out of clothes dryer 10 through a vent 49 defined by cabinet 12.
Front duct 46 and exhaust duct 48 form a conduit 47 that extends between and connects chamber 27 of drum 26 and vent 49. Conduit 47 places chamber 27 of drum 26 and vent 49 in fluid communication in order to permit moisture laden air Am to exit dryer appliance 10. Air handler 42 is in fluid communication with conduit 47, and impeller 43 of air handler 42 is positioned within conduit 47.
A cycle selector knob 50 is mounted on a cabinet backsplash 52 and is in communication with a controller 54. Signals generated in controller 54 operate motor 28 and heater assembly 34 in response to a position of selector knob 50. Alternatively, a touch screen type interface may be provided. As used herein, “processing device” or “controller” may refer to one or more microprocessors or semiconductor devices and is not restricted necessarily to a single element. The processing device can be programmed to operate dryer appliance 10. The processing device may include, or be associated with, one or memory elements such as e.g., electrically erasable, programmable read only memory (EEPROM).
Referring now generally to
As shown in
As illustrated, fan housing 104 defines a volute 120 of fan housing 104 that is sized and configured for receiving impeller 118. Impeller 118 includes a base plate 122 and a plurality of blades 124 extending therefrom. More specifically, the plurality of blades 124 extend from base plate 122 toward the fan inlet 110 substantially along the axial direction A. Base plate 122 and blades 124 thereby define a plurality of passages 126 for directing the flow of air F during rotation of impeller 118 about the axial direction A. Blades 124 are spaced apart from each other, e.g., along the circumferential direction C. In particular, blades 124 may be spaced apart from each other such that blades 124 are uniformly dispersed or distributed along the circumferential direction C. Blades 124 may be any size, shape, and orientation suitable for drawing the flow of air F in through fan inlet 110 during rotation of impeller 118 about the axial direction A. For example, as illustrated, each of the plurality of blades 124 define a concave surface 134 oriented toward a direction of rotation (indicated by arrow 132 in
Impeller 118 may be placed in mechanical communication with a motor, such as motor 28, that selectively rotates impeller 118 about an axial direction A within fan housing 104. For example, according to the illustrated embodiment, base plate 122 has a substantially circular shape, e.g., in a plane that is perpendicular to the axial direction A, such that base plate 122 is substantially disk-shaped. Base plate 122 includes a mounting feature 128 for mounting base plate 122 to a motor, such as motor 28. Mounting feature 128 is positioned at a center 130 of base plate 122 and can be any suitable mechanism for mounting impeller 118 to motor 28. For example, mounting feature 128 may include threads for securing impeller 118 to motor 28. In this manner, impeller 118 is rotated about axis of rotation in the direction of rotation 132. In this manner, impeller 118 may draw the flow of air F into impeller 118 along the axial direction A.
During operation of fan assembly 100, impeller 118 may rotate about the axial direction A within volute 120 of fan housing 104 such that impeller 118 draws the flow of air F into fan housing 104 via fan inlet 110. In addition, impeller 118 may urge the flow of air F through fan housing 104 to fan outlet 112 and exhaust duct 106 during operation of fan assembly 100. More specifically, the flow of air F may flow into fan housing 104 flowing along a direction that is substantially parallel to the axial direction A. Within volute 120, the flow of air F may be urged outward along the radial direction R, along directions that are perpendicular to the axial direction A.
Inlet duct 102, fan housing 104, and exhaust duct 106 may be constructed of or with any suitable material. For example, these components may be constructed of or with a single continuous or integral piece of plastic. Alternatively, inlet duct 102, fan housing 104, and exhaust duct 106 may be separate parts that are mechanically joined, e.g., by using mechanical fasteners or by welding. According to alternative exemplary embodiments, these components may also be constructed of a metal, such as steel.
Referring now generally to
As illustrated in
As illustrated in
According to an exemplary embodiment, guide vane 150 is positioned and oriented for directing the flow of air F onto or towards top portion 164 of curved end wall 162. In this manner, as shown in
According to various embodiments of the present subject matter, guide vane 150 may be any suitable size and shape. In addition, one or multiple guide vanes may be positioned and oriented in any suitable manner to achieve the results described. For example, guide vane 150 may define a length along the lateral direction L that is approximately the same as the diameter of impeller 118. Alternatively, the length of guide vane 150 along the lateral direction L may be shorter or longer than the diameter of impeller 118. For example, according to the illustrated embodiment, the length of guide vane 150 along the lateral direction L is approximately two times the diameter of impeller 118.
Guide vane 150 may extend across a depth of inlet duct 110. More specifically, inlet duct 110 may include a first side wall 170 (
According to the illustrated embodiment, guide vane 150 always extends in a plane that is substantially perpendicular to an inner surface of first sidewall 170. In this manner, guide vane 150 generally directs the flow of air F in a plane perpendicular to the axial direction A, but has little effect on the direction of flow along the axial direction A. However, according to alternative embodiments, guide vane 150 may twist or extend along a plane that is not perpendicular to the inner surface of first side wall 170. For example, according to an exemplary embodiment, guide vane 150 may twist about an axis parallel to the radial direction R or may extend from first side wall 150 at an angle of approximately sixty degrees.
Operation of dryer appliance 10 having a fan assembly 100 and guide vane 150 according to exemplary embodiment illustrated in
As illustrated in
Although
Referring now to
According to the illustrated embodiment, guide vanes 190 comprise two vanes that are spaced equidistant between bottom wall 174 and top wall 176. In this manner, guide vanes 190 define passageways 194 that are configured to “straighten” the flow of air F prior to entering inlet chamber 160. More specifically, the flow of air F entering inlet duct 102 from chamber 27 is typically turbulent. This turbulence can result in instable performance of fan assembly 100, particularly in the stall region of the fan curve (see
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.
