Patent Application
20220349411
The present invention is related to air-moving appliances. More specifically, it is related to window fans. Even more specifically, it is related to dual window fans.
Window fans are well known. Such fans of the prior art are placed in an open or partially open window, and in the case of a sliding or casement window the window is then partially closed against the fan. The fan is then energized to either blow fresh air into the room or to blow stale air out of the room.
Dual window fans are also known and include two side-by-side fans which are intended to provide increased airflow.
Dual window fans are also known in which one or both of the fans are electrically reversible to allow for a selected one of inflow or outflow.
A drawback in such arrangements is that the airflow into the room creates positive air pressure within the room which then impedes further inflow, and the airflow out of the room creates negative air pressure within the room which then impedes further outflow.
Dual window fans are also known in which the fans are each independently electrically reversible to allow for simultaneous inflow and outflow to thereby reduce such impedance.
Among the drawbacks in such arrangement are that reversible motors are more complex and expensive to manufacture, that fan blades are most efficient and effective when designed to move air in a single direction and when moving air in that direction, and that motors are most efficient and effective when coupled with a single-direction fan blade operating in its intended direction
There exists a need for, and it is an object of the invention to provide, a window fan which allows air exchange between the room and outdoors without requiring reversible motors or 2-way fan blades.
There also exists a need for, and it is an object of the invention to provide, such a window fan which allows for directional adjustment of the incoming airflow.
There also exists a need for, and it is an object of the invention to provide, such a window fan which allows for the directional adjustment to be into a plurality of incoming airflow directions.
Further needs and objects exist which are addressed by the present invention, as may become apparent upon review of the included disclosure of exemplary embodiments thereof.
The invention may be embodied in or practiced using an electrical window fan having two pivotable fan heads which are each arranged to blow air therethrough and which each may be pivoted independently of the other both leftwardly or rightwardly to direct incoming airflow in a selected direction, or which each may be pivoted independently of the other to face outdoors and cause an outflow, and which may be pivoted relative to each other so that one causes inflow while the other causes outflow.
The invention may also be embodied in or practiced using a window fan having a rectangular body adapted to engage a window within an opening thereof and a plurality of fan heads pivotably engaging the body independently of each other each adapted to cause airflow through the body either inwardly when pivoted inwardly and outwardly when pivoted outwardly. The fan heads may each be pivotable relative to the body about a vertical pivot axis. The fan heads may each be pivotable from aiming directly outwardly normal to the body to aiming inwardly through a pivot angle of at least 225 angular degrees. Each fan head may include a non-reversible motor coupled to a fan blade and adapted to rotate the fan blade only in a single rotational direction to cause an airflow through the associated fan head only in one axial direction relative to the associated fan head. Each fan head may have intake and exhaust openings and each fan blade may have five fan vanes equally-spaced about the blade and shaped with a concave downwind face and convex upwind face for optimal airflow from the intake opening to the exhaust opening. Each fan head may have spirally-curved intake and exhaust vanes and cylindrical duct surrounding its associated fan blade, the intake and exhaust vanes curved in the single rotational direction, such that the rotating fan blade, duct, and vanes cooperate to cause helical collimation of the airflow. The window fan may have expandible side panels adapted for extension from the body to cover any portion of the opening that the body does not. The window fan may have bug screens adapted for selective affixation to the body over the intake opening of each fan head and dome shaped to allow pivoting of the fan head.
Further features and aspects of the invention are disclosed with more specificity in the Detailed Description and accompanying drawings of an exemplary embodiment provided herein.
Many aspects of the invention can be better understood with reference to the included Drawings showing an exemplary embodiment for practicing the invention which corresponds to the accompanying Detailed Description. The components in the Drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the invention. Moreover, like reference numerals in the Drawings designate corresponding parts throughout the several views.
A window fan 100 is shown in
The vertical pivot axis enables an axial incoming airflow to be aimed at any of a wide angle of directions withing the room to cool persons regardless of their position in the room, whereas an alternative horizontal pivot angle would only allow upward and downward pivoting which could only cool persons directly in front of the fan.
The rectangular body is adapted for placement into the opening of a partially or fully-opened window. In the case where the opening is wider than the body, the expandible side panels may be extended from the sides of the body as needed to cover any portion of the opening that the body does not.
Each fan head includes a motor 112 and a fan blade 114. While these are identical in each fan head in both shape and direction, it is anticipated that one blade/motor could be configured to rotate opposite the other, with one fan blade being the mirror image of the other, if desired for symmetry. The blade rotates clockwise when viewed from the front as of
The fan blade is shaped for optimal, most efficient, and fastest airflow from the motor side through the blade. In other words, it is a “one-way” blade. This is accomplished by the concavity R1 of the forward (downwind) face 116 and the convexity R2 or rear (upwind) face 117 of the fan blade vanes 118 as best seen in
Each fan includes five fan blade vanes equally spaced around the blade, which is found superior in achieving proper balance of the blade during rotation because slight unintended inequalities between the blades are more easily forgiven be such an uneven and pentagonally-disposed arrangement.
The pivoting of the head to aim either inward or outward as desired while the motor/blade rotates in the same direction at all times is thereby superior to the alternative of reversing motor/blade rotation because a more expensive and less reliable reversible motor and a less efficient two-way blade are not needed.
The intake face 122 and exhaust face 124 of each fan head include spirally-curved vanes 126 which curve in the direction of the motor/blade rotation and the fan blade is positioned within cylindrical duct 128. This causes a helical collimation of the exhausted airflow 130, which enables it to reach further into the room at a higher velocity during inward operation than would the turbulent airflow from a common free-flow fan. Such a collimated airflow is quieter than a common turbulent airflow. And this is accomplished without sacrificing the air volume, which is important for ventilation.
Various changes in form and detail may be made without departing from the spirit and scope of the invention, so the invention should therefore only be considered according to the following claims, including all equivalent interpretation to which they are entitled.
| Number | Date | Country | |
|---|---|---|---|
| 63182041 | Apr 2021 | US |
