Patent Description:
Disclosed is an aircraft including ductwork, as claimed in claim <NUM>. The ductwork includes a fresh air intake disposed to draw air from offboard the aircraft. The ductwork includes a cabin recirculation vent disposed to draw air from an aircraft cabin. The ductwork includes a riser defining a return conduit disposed to convey air from the cabin recirculation vent and join the fresh air intake. The ductwork includes an overhead outlet vent connected to the riser and disposed to expel air into the cabin, the overhead outlet vent being connected to the riser downstream of where the riser joins the fresh air intake. The aircraft includes a thermoelectric heat pump having a first side and a second side, the first side in thermal contact with the return conduit that transfers heat to the second side upon application of an electrical input.

The aircraft further includes an exhaust defining an exhaust conduit joined with the ductwork and disposed to expel air from the aircraft cabin offboard the aircraft, and the second side is in thermal contact with the exhaust conduit and transfers heat to the exhaust conduit.

In addition to the features described above, further embodiments may include that the cabin recirculation vent is divided by the thermoelectric heat pump defining a riser vent portion associated with the riser and an exhaust vent portion associated with the exhaust.

In addition to one or more of the features described above, further embodiments may include a switch operable to complete a circuit associated with the thermoelectric heat pump. In addition to one or more of the features described above, or as an alternative, further embodiments may include an operations controller having stored instructions operable upon execution to operate the switch to complete the circuit such that the electrical input causes the first side to transfers heat to the second side.

In addition to one or more of the features described above, further embodiments may include that the switch is operated responsive to a temperature sensor indication falling below a selected temperature threshold corresponding to an environmental temperature associated with the cabin recirculation vent.

In addition to one or more of the features described above, further embodiments may include that an operations controller having stored instructions operable upon execution to operate a current controller associated with the thermoelectric heat pump such that current output from the operations controller is increased based on a temperature sensor indication increase corresponding to an environmental temperature associated with the cabin recirculation vent.

An aircraft may be configured to provide fresh air to the passenger cabin by displacing existing air in the cabin. The existing cabin air may be filtered and recirculated or exhausted out of the aircraft. As an example, half of the cabin air may be filtered and recirculated to the cabin, while the other half is discharged offboard the aircraft.

Fresh air may be mixed with the recirculated air to maintain proper quantities of air mass within the cabin and to provide sufficient supply of fresh air to maintain cabin atmosphere and comply with ventilation specifications. The mixed air may be temperature adjusted based on temperature settings of occupants near vents discharging the mixed air or sensors that detect the temperature of the cabin air. A thermoelectric heat pump may be configured to change a temperature of air within ductwork associated with the recirculated air and discharge the corresponding thermal energy to the exhaust ductwork.

Referring to <FIG>, an aircraft <NUM> is shown. The aircraft <NUM> includes an aircraft cabin <NUM>. The aircraft cabin <NUM> may include any accessible area of the aircraft, including, as an example, the cockpit. The aircraft <NUM> includes ductwork <NUM> for handling air between ingress and egress points. The ductwork <NUM> includes a cabin recirculation vent <NUM>. The cabin recirculation vent <NUM> may include an orifice <NUM> and associated ducting <NUM> for connecting with the ductwork <NUM>. The ducting <NUM> may be divided by a thermoelectric heat pump <NUM> into a riser vent portion <NUM> and an exhaust vent portion <NUM>. The cabin recirculation vent <NUM> is situated to draw air from the aircraft cabin <NUM>. As an example, the cabin recirculation vent <NUM> may be situated near the dado panels <NUM> of the aircraft cabin <NUM>. The dado panel <NUM> may be a lower portion of a sidewall of the aircraft cabin <NUM>, as shown in <FIG>. The cabin recirculation vent <NUM> is attached to a riser <NUM>. The riser <NUM> directs air from the cabin recirculation vent <NUM> to junction or mixer <NUM>. The mixer <NUM> combines fresh air from a fresh air intake <NUM> with the air from riser <NUM>. The fresh air intake <NUM> draws air from offboard the aircraft <NUM>.

It should be appreciated that any number of dampers, fans, or other air controllers may be used to alter the flow of air through the ductwork. An ejector or Venturi effect configuration may force air through one of the riser <NUM>, fresh air intake <NUM>, or exhaust <NUM>. The air controllers may control air within the mixer such that <NUM>% of the output air is recirculated air from the riser <NUM> and <NUM>% of the output air is fresh air from the fresh air intake <NUM>. The exhaust <NUM> air stream may be propelled by a positive pressure difference between the cabin and the outside environment. Air from the mixer <NUM> is directed to the overhead outlet vent <NUM> through riser <NUM> and recirculated throughout cabin <NUM>.

It should be appreciated that the fresh air intake <NUM> or exhaust <NUM> may be disposed above, below, or among the cabin walls, floor, and ceiling. The fresh air intake <NUM> or exhaust <NUM> may be disposed beneath the cabin floor. The fresh air intake <NUM> or exhaust <NUM> may be disposed above the cabin.

The cabin recirculation vent <NUM> also dispenses air to an exhaust <NUM> that defines an exhaust conduit <NUM>. Air controllers may be used to control flow among the riser <NUM> and the exhaust conduit <NUM>. The riser <NUM> may define a return conduit <NUM>, or portion thereof, for recirculation to the aircraft cabin <NUM>. The air controllers may control air between the riser <NUM> and the exhaust conduit <NUM> such that <NUM>% of mass flow from the cabin recirculation vent <NUM> travels through the return conduit <NUM> and <NUM>% of mass flow from the cabin recirculation vent <NUM> travels through the exhaust conduit <NUM>.

A thermoelectric heat pump <NUM> is provided and may be disposed near the cabin recirculation vent <NUM>. The thermoelectric heat pump <NUM> may include any thermoelectric material. That is, any material that causes recognizable voltage based on a temperature differential. For example, the thermoelectric heat pump <NUM> may include semiconductor portion <NUM>. The semiconductor portion <NUM> may be any type of semiconductor material. For example, the semiconductor portion <NUM> may include disparately doped silicon. The semiconductor portion <NUM> may be sandwiched by a first side <NUM> and a second side <NUM>. The first side <NUM> is in thermal contact with the return conduit <NUM> such that heat energy is conducted between the first side <NUM> and the return conduit <NUM> or air within the return conduit <NUM>. The second side <NUM> is in thermal contact with the exhaust conduit <NUM> such that heat energy is conducted between the second side <NUM> and the exhaust conduit <NUM> or air within the exhaust conduit <NUM>. The riser <NUM> or exhaust <NUM> may be configured to provide counter flow to one another. That is, the riser <NUM> or the exhaust <NUM> may be configured in an S-shape or a U-shape to reduce temperature gradients across the thermoelectric heat pump <NUM> such that the flow of air across the first side <NUM> is opposite the flow of air across the second side <NUM>. As such, air from the cabin recirculation vent <NUM> is divided with desired heating or cooling of the return conduit <NUM> air with undesirable thermal products being discarded with the exhaust conduit <NUM>. It should be appreciated that any configuration, disposition, or orientation of the thermoelectric heat pump <NUM> may adjust the temperature of the return conduit <NUM> air, as long as it is within the scope of the claims. It should be appreciated that the thermoelectric heat pump <NUM> may be disposed above, below, or among the cabin walls, floor, and ceiling. It should be appreciated that <FIG> is not shown to scale and all of the associated ductwork <NUM> is located within, near, or around the fuselage. The present depiction is to improve clarity. It should be appreciated that a heat exchanger or radiator may be attached to either the first side <NUM> or the second side <NUM> to improve heat transfer.

Referring to <FIG>, an aircraft cabin <NUM> is shown. The aircraft cabin <NUM> includes a sidewall <NUM>. The sidewall <NUM> may include a dado panel <NUM>. The dado panel <NUM> may be situated on a lower half portion of the sidewall <NUM> or a portion thereof. The cabin recirculation vent <NUM> is disposed on the dado panel <NUM> drawing air from the cabin <NUM> to the riser <NUM> and into the return conduit <NUM>. The riser <NUM> is positioned between the first window <NUM> and the second window <NUM>. The riser <NUM> may also be positioned on a non-windowed portion of sidewall <NUM>. The section of sidewall <NUM> may be associated with a temperature sensor <NUM>. The temperature sensor <NUM> may provide a temperature sensor indication <NUM> (as shown in <FIG>) of the environment or provide an environmental temperature of the surrounding aircraft cabin <NUM>. The recirculated air travels through riser <NUM> and enters the cabin <NUM> through the overhead outlet vent <NUM>. It should be appreciated that the cabin recirculation vent <NUM> and the overhead outlet vent <NUM> may be positioned anywhere within the cabin <NUM> or the aircraft <NUM>.

Referring to <FIG>, a schematic diagram of a thermoelectric heat pump <NUM> is shown. The thermoelectric heat pump <NUM> may include a semiconductor portion <NUM> sandwiched by a first side <NUM> and a second side <NUM>. Conductive plates <NUM> may be disposed between the semiconductor portion <NUM> and the first side <NUM> and the second side <NUM>, as shown. N-doped semiconductor material <NUM> and p-doped semiconductor material <NUM> may be placed between the conductive plates <NUM> to provide a serial conductive path <NUM> through the N-doped semiconductor material <NUM> and p-doped semiconductor material <NUM> material. The conductive path <NUM> serves as an electrical input to the thermoelectric heat pump <NUM> and forms a circuit.

The conductive path <NUM> may be controlled by current controller <NUM>. The current controller <NUM> may include a switch. The current controller <NUM> may be an amplifier, operational amplifier, or otherwise disposed transistor configured to alter, multiply, or obstruct current flowing through conductive path <NUM>. The current controller <NUM> may include a power source or be associated with an aircraft power source to energize the conductive path <NUM>. The power source may be connected to an auxiliary bus of the aircraft. It should be appreciated that any type of current controller <NUM> may be used. Current controller <NUM> is operated by operations controller <NUM> through control channel <NUM>. The control channel <NUM> may be digital or analog. The control channel <NUM> may include additional components (e.g., gate drivers) for operating the current controller <NUM>.

The controllers <NUM>, <NUM> may include any combination of processors, field programmable gate arrays (FPGA), or application specific integrated circuits (ASIC). The controller may include memory, volatile and non-volatile, operable to store machine instructions from the processors and other processing mechanisms to receive, calculate, and control devices, as necessary. Machine instructions may be stored (e.g., stored instructions, stored machine instructions, stored steps) in any language or representation, including but not limited to machine code, assembly instructions, C, C++, C#, PASCAL, COBAL, PYTHON, JAVA, and RUBY. It should be appreciated that any type of wired or wireless configuration is appreciated for any of the communications from the controller. Wireless protocols such as ZIGBEE, WI-FI, BLUETOOTH, or any other implement may be used. Communications may be realized through any protocol or medium known or unknown.

The operations controller <NUM> may receive a temperature sensor indication <NUM> from temperature sensor <NUM>. The temperature sensor <NUM> may also be a temperature setting or request operated by an aircraft cabin <NUM> occupant. For example, the occupant may desire an increase or decrease in surrounding temperature and adjust the temperature through controls associated with the temperature sensor <NUM>. The temperature sensor <NUM> may be any type of temperature sensing device including thermocouples and resistive thermal devices. The operations controller <NUM> may be configured to increase or decrease current output along the conductive path <NUM> from current controller <NUM> based on the temperature sensor indication <NUM>. It should be appreciated that the temperature sensor indication <NUM> may be received wirelessly or from any number of wireless devices to properly control the thermoelectric heat pump. For example, ZIGBEE or BLUETOOTH devices may be dispersed throughout the aircraft <NUM> to send such signals.

As an example, the aircraft cabin <NUM> may have a temperature threshold or temperature setting of <NUM>° C (<NUM>° F), if the cabin temperature increases to <NUM>° C (<NUM>° F), the operations controller <NUM> may include stored instructions to operate the current controller <NUM> to increase current output along current path <NUM>. As such, the thermoelectric heat pump will increase the cool (or heating) necessary to decrease (or increase) the temperature of air flowing through the return conduit <NUM>. It should be appreciated that the first side <NUM> and the second side <NUM> may also include radiators that extend into the respective conduits.

Referring to <FIG>, a method <NUM> is shown. The method <NUM> begins in step <NUM>. In step <NUM>, a selected temperature threshold is received by the operations controller <NUM>. The selected temperature threshold may be set by an occupant through a human interface, operable to enable a user to set a selected temperature threshold. The selected temperature threshold may be set wirelessly.

In step <NUM>, the operations controller <NUM> receives a temperature sensor indication <NUM> from the temperature sensor <NUM>. The temperature sensor indication <NUM> may be sent via wireless, wired, digital, or analog mediums. In step <NUM>, if the temperature sensor indication <NUM> is different from the threshold the operations controller <NUM> may operate the thermoelectric heat pump <NUM> to properly adjust the temperature. For example, if the temperature is too high, the thermoelectric heat pump <NUM> may be operated to lower the temperature. If the temperature is too low, the thermoelectric heat pump <NUM> may be operated to raise the temperature.

For example, if the indication is above the threshold in step <NUM>, the operations controller <NUM> may operate the current controller <NUM> to increase current through the thermoelectric heat pump <NUM> and direct the current in a proper direction such that cooling is provided to return conduit <NUM>. In step <NUM>, the operations controller <NUM> determines whether the temperature sensor indication <NUM> is less than the threshold such that the current can be adjusted in step <NUM> to reduce the temperature change from the thermoelectric heat pump <NUM>. It should be appreciated that current may be increased depending on the disparity or rate of change of temperature against the threshold. These steps may be adjusted, omitted, rearranged, repeated, or otherwise follow any order or sequence to complete necessary functions.

Claim 1:
An aircraft comprising:
ductwork (<NUM>) including:
a fresh air intake (<NUM>) disposed to draw air from offboard the aircraft (<NUM>),
a cabin recirculation vent (<NUM>) disposed to draw air from an aircraft cabin (<NUM>),
a riser (<NUM>) defining a return conduit (<NUM>) disposed to convey air from the cabin recirculation vent (<NUM>) and join the fresh air intake (<NUM>), and
an overhead outlet vent (<NUM>) connected to the riser (<NUM>) and disposed to expel air into the cabin (<NUM>), the overhead outlet vent (<NUM>) being connected to the riser (<NUM>) downstream of where the riser (<NUM>) joins the fresh air intake (<NUM>),
characterized by
a thermoelectric heat pump (<NUM>) having a first side (<NUM>) and a second side (<NUM>), the first side (<NUM>) in thermal contact with the return conduit (<NUM>) that transfers heat to the second side (<NUM>) upon application of an electrical input; and
an exhaust (<NUM>) defining an exhaust conduit (<NUM>) joined with the ductwork and disposed to expel air from the aircraft cabin (<NUM>) offboard the aircraft (<NUM>), and the second side (<NUM>) is in thermal contact with the exhaust conduit (<NUM>) and transfers heat to the exhaust conduit (<NUM>).