Patent Description:
Conventional evacuation systems of aircraft generally include an inflatable device, such as an evacuation slide, an aspirator for inflating the inflatable device, and a source of compressed gas (e.g., one or more tank of compressed gas). In response to the evacuation system becoming deployed, the source of compressed gas may release gas through the aspirator, which then also draws air from the environment of the aspirator and inflates the inflatable device using the decompressed gas and the air. However, use of compressed gas storage tanks may be undesirable for various reasons. For example, the storage tanks may undesirably increase a total weight of the aircraft. Additionally, the storage tanks may be difficult to store and transport on board the aircraft.

The document <CIT> discloses a fan according to the preamble of claim <NUM>.

The present invention provides a fan aspirator according to claim <NUM>, hence a fan aspirator that includes a housing, a fan, a pinion gear, and at least one motor. The housing defines a central channel and has a central longitudinal axis, according to various embodiments. The fan is disposed in the central channel and is configured to rotate about a rotational axis that is substantially parallel to the central longitudinal axis. The pinion gear is coupled to the fan and is configured to rotate with the fan, with the pinion gear comprising an annular body with a gear track. The at least one motor comprises a drive gear, with the motor being coupled to the housing and the drive gear being mechanically coupled to the gear track of the annular body of the pinion gear, wherein the fan is configured to be driven via the drive gear and the pinion gear. Further features of the inventive fan aspirator are specified in claim <NUM>.

In various embodiments, the motor is a first motor of a plurality of motors having a respective plurality of drive gears. The plurality of motors may be coupled to the housing and may be distributed circumferentially around the rotational axis such that each drive gear of the respective plurality of drive gears is mechanically coupled to the gear track of the annular body of the pinion gear. In various embodiments, the plurality of motors comprises at least <NUM> motors. In various embodiments, the plurality of motors comprises at least <NUM> motors.

In various embodiments, the gear track is disposed on a radially outward surface of the annular body of the pinion gear such that the plurality of motors are circumferentially distributed around a periphery of the pinion gear. According to the invention, a radially inward surface of the annular body of the pinion gear is radially outward of tips of fan blades of the fan such that a radial gap is defined between the tips of the fan blades and the radially inward surface of the annular body of the pinion gear. In various embodiments, a radially inward surface of the central channel of the housing at an axial location of fan blades of the fan is radially outward of tips of the fan blades such that a radial gap is defined between the tips of the fan blades and the radially inward surface of the central channel of the housing at the axial location of the fan blades. In various embodiments, a radially inward surface of the annular body of the pinion gear is radially outward of a radially inward surface of the central channel of the housing at an axial location of the pinion gear.

The fan aspirator may further include a controller electrically coupled to the plurality of motors. The controller may be configured to synchronize angular speed of the plurality of motors. In various embodiments, a gear ratio of the fan aspirator is between <NUM> and <NUM>. In various embodiments, a gear ratio of the fan aspirator is between <NUM> and <NUM>. In various embodiments, a gear ratio of the fan aspirator is about <NUM>.

Also disclosed herein, according to various embodiments, is a system for inflating an inflatable device. The system may include an inflatable device and a fan aspirator according to claim <NUM>. The fan aspirator may be coupled to the inflatable device, and may include a housing, a fan, a pinion gear, and a plurality of motors. The housing may define a central channel and may have a central longitudinal axis. The fan may be disposed in the central channel and may be configured to rotate about a rotational axis that is substantially parallel to the central longitudinal axis. The pinion gear, according to various embodiments, is coupled to the fan and configured to rotate with the fan, with the pinion gear comprising an annular body comprising a gear track. The plurality of motors may include a respective plurality of drive gears. The plurality of motors are coupled to the housing and are distributed circumferentially around the rotational axis such that each drive gear of the respective plurality of drive gears is mechanically coupled to the gear track of the annular body of the pinion gear, according to various embodiments.

In various embodiments, the system also includes an electrical power source electrically coupled to the motor. In various embodiments, the system further includes a controller electrically coupled to the plurality of motors and configured to synchronize angular speed of the plurality of motors. The plurality of motors may include at least <NUM> motors, and the gear ratio of the driven pinion gear to the drive gears may be between <NUM> and <NUM>.

In the following, the word "embodiment" simply means "example" and does not mean "embodiment of the invention".

The subject matter of the present invention is defined by the appended claims. present disclosure, however, may best be obtained by referring to the detailed description when considered in connection with the drawing figures.

The detailed description of exemplary embodiments herein makes reference to the accompanying drawings, which show exemplary embodiments by way of illustration. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, it should be understood that other embodiments may be realized and that logical changes and adaptations in design and construction may be made in accordance with this disclosure and the teachings herein.

Disclosed herein, according to various embodiments, is a fan aspirator, and related systems and methods, which utilizes one or more motors to drive a fan of the aspirator to deliver inflation fluid to an inflatable device. Generally, the fan aspirator includes a plurality of motors and a respective plurality of drive gears configured to drive a pinion gear coupled to a fan disposed within the housing of the fan aspirator. Although numerous details and examples are included herein pertaining to utilizing these concepts in conjunction with inflatable devices of aircraft evacuation systems, the present disclosure is not necessarily so limited, and thus aspects of the disclosed embodiments may be adapted for performance in a variety of other industries. As such, numerous applications of the present disclosure may be realized.

Referring now to <FIG>, an aircraft <NUM> is shown. The aircraft <NUM> may include a fuselage <NUM> having a plurality of exit doors including an exit door <NUM>. The aircraft <NUM> may include one or more evacuation systems positioned near a corresponding exit door or located anywhere in or on the fuselage <NUM>. For example, the aircraft <NUM> includes an evacuation system <NUM> positioned near the exit door <NUM>, and may include another evacuation system positioned in the fuselage <NUM> and designed to inflate outside of the fuselage to provide at least one of egress or flotation. The evacuation system <NUM> may be removably coupled to the fuselage <NUM>. In the event of an emergency, the exit door <NUM> may be opened by a passenger or crew member of the aircraft <NUM>. In various embodiments, the evacuation system <NUM> may deploy in response to the exit door <NUM> being opened and, in various embodiments, the evacuation system <NUM> may deploy in response to another action taken by a passenger or crew member such as depression of a button or actuation of a lever.

Turning to <FIG>, additional details of the evacuation system <NUM> are illustrated. In particular, the evacuation system <NUM> includes an inflatable device <NUM>. The evacuation system <NUM> further includes a fan aspirator <NUM>, a controller <NUM>, a pressure sensor <NUM>, and a power source <NUM>. The inflatable device <NUM> may be coupled to the fuselage <NUM> of <FIG>, and may be decoupled from the fuselage <NUM> in response to being fully inflated or to being manually detached in order to allow passengers and/or crew members to safely float away from the aircraft <NUM> of <FIG>. In various embodiments, the inflatable device <NUM> may be permanently coupled to the fuselage <NUM>. In various embodiments, the inflatable device <NUM> may function as a slide from the fuselage <NUM> to a ground surface upon which the aircraft <NUM> is resting. In various embodiments, the inflatable device <NUM> may be entirely decoupled from the fuselage <NUM> at all times, may be removed from a cabin by a passenger or crew member, and may be inflated away from the fuselage.

Details regarding the fan aspirator <NUM> (which may be a ducted fan aspirator) will be discussed in more detail below. The controller <NUM> may include one or more processors and one or more tangible, non-transitory memories and be capable of implementing logic. The processor can be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The pressure sensor <NUM> may include any sensor capable of detecting data corresponding to a pressure within the inflatable device <NUM> (the air within the inflatable device <NUM> may be referred to as "device air"). The controller <NUM> may be coupled to the fan aspirator <NUM> and may control the aspirator <NUM>. In various embodiments, the controller <NUM> may further be coupled to the pressure sensor <NUM>, may determine the pressure within the inflatable device <NUM> based on the detected pressure data, and may control the fan aspirator <NUM> based on the determined pressure. The power source <NUM> may include any power storage device such as one or more of a battery (e.g., a lithium polymer battery), a flywheel, or a capacitor. In various embodiments, the power source <NUM> may include any power generation device such as a generator. The power source <NUM> may provide electrical energy to the motor(s) of the fan aspirator <NUM>, the controller <NUM>, and/or the pressure sensor <NUM> to facilitate operation of these elements. In various embodiments, fan aspirator may be coupled to an electrical power line to receive electrical energy.

Referring to <FIG>, the inflatable device <NUM> is illustrated as fully inflated and separated from the fuselage <NUM> of <FIG>. In particular, the fan aspirators <NUM>, the controller <NUM>, the pressure sensor <NUM>, and the power source <NUM> may remain coupled to the inflatable device <NUM>. In various embodiments, one or more of these elements of the evacuation system <NUM> may become detached from the inflatable device <NUM> before, during, or after inflation.

Referring briefly to <FIG>, another inflatable device <NUM> is shown as inflated. The inflatable device <NUM> may provide egress from an aircraft in various situations. In various embodiments, the inflatable device <NUM> may include similar features as the inflatable device <NUM> of <FIG>. In that regard, the inflatable device <NUM> may include a fan aspirator <NUM>. The inflatable device <NUM> may further include a controller <NUM>, a pressure sensor <NUM>, and a power source <NUM>. The inflatable device <NUM> may be coupled to a fuselage of an aircraft, and may be decoupled from the fuselage in response to being fully inflated or to being manually detached in order to allow passengers and/or crew members to safely float away from the aircraft. In various embodiments, the inflatable device <NUM> may be permanently coupled to the fuselage. In various embodiments, the inflatable device <NUM> may function as a slide from the fuselage to a ground surface upon which the aircraft is resting.

Referring now to <FIG>, <FIG>, and <FIG>, details of the fan aspirator are provided. With specific reference to <FIG>, the fan aspirator <NUM> generally includes a housing <NUM> defining a central channel within which a fan is disposed. The housing <NUM> generally extends from an inlet end <NUM> to an outlet end <NUM>, according to various embodiments, and thus the fan aspirator may be referred to herein as a ducted fan aspirator. The housing <NUM> may extend from the inlet end <NUM> that is disposed outside <NUM> of the inflatable device <NUM> to the outlet end <NUM> disposed within an internal volume <NUM> of the inflatable device <NUM>. The fan aspirator <NUM> may also include an attachment flange <NUM> that facilitates connecting the fan aspirator <NUM> to the inflatable device <NUM>. As described in greater detail below, the fan aspirator <NUM> includes a pinion gear <NUM> coupled to the fan and at least one motor <NUM> with a drive gear <NUM>. The motor(s) <NUM> may drive the drive gear(s) <NUM>, and the drive gears(s) <NUM> are mechanically coupled to the pinion gear <NUM> to drive rotation of the fan, thereby inducing airflow from the inlet end <NUM> to the outlet end <NUM> to cause the inflatable device <NUM> to inflate.

The motor(s) may receive electrical energy and convert the electrical energy into mechanical power to drive the fan via the drive gear(s) and the pinion gear. The fan aspirator may further include a fan flap located proximate the fan inlet <NUM>. The fan flap may allow airflow to flow downstream (i.e., from the inlet <NUM> towards the outlet <NUM>) and may reduce the likelihood of air flowing upstream (i.e., from the outlet <NUM> to towards the inlet <NUM>).

In various embodiments, and with reference to <FIG> and <FIG>, the fan <NUM> may be disposed within the central channel defined by the housing <NUM>. The pinion gear <NUM>, which may comprise an annular body <NUM>, may be mounted to the fan <NUM> such that the fan <NUM> and the pinion gear corotate. The rotational axis <NUM> of the fan <NUM> may be parallel with (and may be coaxial with) the central longitudinal axis of the housing <NUM>. In various embodiments, the fan aspirator <NUM> includes a plurality of motors <NUM> with a respective plurality of drive gears <NUM>. The plurality of motors <NUM> may be coupled and/or mounted to the housing <NUM> and may be generally distributed circumferentially around the rotational axis <NUM> of the fan <NUM>. Each of the drive gears <NUM> may be mechanically coupled to a gear track of the pinion gear <NUM>, thus collectively driving rotation of the pinion gear <NUM> and the fan <NUM> mounted thereto.

In various embodiments, the fan aspirator <NUM> includes <NUM> or more motors and respective drive gears. In various embodiments, the fan aspirator includes between <NUM> and <NUM> motors and respective drive gears. In various embodiments, the fan aspirator includes <NUM> motors. In various embodiments, the fan aspirator includes <NUM> motors. By having a plurality of motors <NUM> driving the central pinion gear <NUM> to which the fan <NUM> is mounted, the fan <NUM> may be driven to reach speeds sufficient to drive enough air into the inflatable device. Further, various other benefits may be realized by using a plurality of circumferentially distributed motors, such as efficiency, power consumption, and weight savings over conventional aspirators that rely on a source of compressed gas, according to various embodiments.

In various embodiments, and with continued reference to <FIG>, the central channel <NUM> defined by the housing <NUM> may have a radial dimension that remains constant along a length of the fan aspirator (e.g., at least along a section of the housing <NUM> at an axial location of the fan blades <NUM>). In various embodiments, the radial dimension of the central channel <NUM> may vary along the length of the fan aspirator <NUM>. In various embodiments, the fan blades <NUM> may have a radial span that is less than the radial dimension of the central channel, and thus a radial gap may exist between the outer edge of the fan blades <NUM> and the radially inward surface of the central channel <NUM>. Thus, as the fan <NUM> directs air through the central channel <NUM>, additional air (i.e., induced air) may flow through the gap, thus increasing a total airflow through the fan aspirator <NUM> beyond that provided solely by the fan <NUM>.

In various embodiments, the gear track of the pinion gear <NUM> is disposed on a radially outward surface of the annular body <NUM> of the pinion gear <NUM>. Said differently, the pinion gear <NUM> may have an annular structure, thus allowing the air/fluid to flow through the central aperture of the pinion gear. However, the pinion gear <NUM> may include one or more structural spokes <NUM> extending radially between the central region of the pinion gear where it connects to the fan and the annular body <NUM>. With the gear track of the pinion gear <NUM> disposed on the radially outward surface of the annular body <NUM>, the respective drive gears <NUM> may be disposed and distributed around the periphery of the pinion gear.

In various embodiments, as mentioned above, the fan aspirator may include a controller electrically coupled to the plurality of motors. The controller may be an electronic speed controller configured to synchronize angular speed of the plurality of motors to efficiently drive rotation of the pinion gear and fan. In various embodiments, a gear ratio of the driven pinion gear relative to the drive gears is between <NUM> and <NUM>. In various embodiments, the gear ratio is between <NUM> and <NUM>. In various embodiments, the gear ratio is about <NUM>.

Regarding relative radial dimension of the assembly, a radially inward surface of the annular body <NUM> of the pinion gear <NUM> is radially outward of tips of fan blades <NUM> of the fan such that a radial gap is defined between the tips of the fan blades <NUM> and the radially inward surface of the annular body <NUM>. In various embodiments, a radially inward surface of the central channel <NUM> of the housing <NUM> (at least at an axial location of the fan blades <NUM>) is radially outward of tips of the fan blades <NUM> such that a radial gap is defined between the tips of the fan blades <NUM> and the radially inward surface of the central channel <NUM> of the housing <NUM> at this location. In various embodiments, a radially inward surface of the annular body <NUM> of the pinion gear <NUM> is radially outward of a radially inward surface of the central channel <NUM> of the housing <NUM> at an axial location of the pinion gear <NUM>. By configuring the relative radial dimensions in one or more of these manners, flow stagnation from the pinion gear is inhibited, thus facilitating increased and improved airflow.

Moreover, where a phrase similar to "at least one of A, B, or C" is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.

In the detailed description herein, references to "one embodiment", "an embodiment", "various embodiments", etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic.

Claim 1:
A fan aspirator (<NUM>, <NUM>, <NUM>) comprising:
a housing (<NUM>, <NUM>) defining a central channel and having a central longitudinal axis;
a fan (<NUM>) disposed in the central channel and configured to rotate about a rotational axis that is substantially parallel to the central longitudinal axis;
a pinion gear (<NUM>, <NUM>) coupled to the fan (<NUM>) and configured to rotate with the fan (<NUM>), wherein the pinion gear (<NUM>, <NUM>) comprises an annular body (<NUM>) comprising a gear track; and
a motor comprising a drive gear, wherein the motor is coupled to the housing (<NUM>, <NUM>) and the drive gear is mechanically coupled to the gear track of the annular body of the pinion gear (<NUM>, <NUM>), wherein the motor is configured to drive the fan (<NUM>) via the drive gear and the pinion gear (<NUM>, <NUM>),
characterised in that
a radially inward surface of the annular body (<NUM>) of the pinion gear (<NUM>) is radially outward of a plurality of tips of fan blades (<NUM>) of the fan (<NUM>) such that a radial gap is defined between the tips of the fan blades (<NUM>) and the radially inward surface of the annular body (<NUM>) of the pinion gear to inhibit flow stagnation from the pinion gear (<NUM>).