Removable aircraft heating system

Abstract

Removable aircraft heating method, comprising: - one or more radiant heating devices (2), each comprising: a heating layer (3); an electrode layer (4) comprising one or more anodes and one or more cathodes; two front and rear protective layers (5, 6) arranged on either side of the assembly formed by the heating layer (3) and the electrode layer (4); - a plastic shell (7) fixed to the front protective layer (5) of the radiant heating device (2); and - removable fixing means (11) for the removable heating system (1; 14) on a support (12; 15a, 15b). Figure for the abstract: Fig 1

Description

Title of the invention: Removable heating system for aircraft Technical field

[0001] The present invention relates, in general, to a heating system for the thermal comfort of a passenger in an aircraft cabin.

[0002] In particular, the invention relates to a removable aircraft heating system comprising a radiant heating device, as well as a leg rest unit of an aircraft seat assembly comprising such a heating system. State of the art

[0003] Radiant electric heating, otherwise known as radiant heating, diffuses heat by radiation.

[0004] This results in a sensation of intense and immediate heat.

[0005] In the field of transportation, there are many radiant heating systems for motor vehicles.

[0006] Conventionally, the motor vehicle is equipped with a heating panel comprising a heating layer and a layer of anode and cathode electrodes interposed between two insulating layers. The heating panel is integrated into the dashboard of the motor vehicle and allows the upper parts of the passenger to be heated.

[0007] However, automotive radiant heating systems are not suitable for use in an aircraft.

[0008] Certification specific to the aeronautical sector is required and requires each device integrated into the aircraft to meet certain airworthiness constraints, in order to guarantee passenger safety.

[0009] The airworthiness constraints concern the mechanical resistance of the device, in particular fire resistance, robustness to temperature stresses and mechanical stresses. They also relate to safety, by guaranteeing that no fire will start at a limited temperature and by guaranteeing a limit temperature that cannot injure the passenger. Finally, the airworthiness constraints impose the removable nature of the device, making it independent and thus certifiable independently of its support.

[0010] In order to facilitate obtaining airworthiness certification, the heating system requires a secure structure that can be removed from its support. Presentation of the invention

[0011] The invention therefore aims to remedy these drawbacks and to propose a radiant heating system making it possible to improve the thermal comfort of a passenger in an aircraft cabin, and adapted to meet aeronautical airworthiness certification requirements, to be safe and easily mounted and dismounted.

[0012] There is therefore proposed a removable heating system for aircraft, comprising:

[0013] - one or more radiant heating devices each comprising:

[0014] a heating layer;

[0015] an electrode layer comprising one or more anodes and one or more cathodes;

[0016] two front and rear protective layers arranged on either side of the assembly formed by the heating layer and the electrode layer;

[0017] - a plastic shell fixed on the front protective layer of the device radiant heating; and

[0018] - means for removable fixing of the removable heating system on a support.

[0019] Advantageously, the material of the front and rear protective layers may be selected from: polyimide, FR-4 glass fiber reinforced epoxy resin composite, polyethylene terephthalate, or a polyurethane thermoplastic.

[0020] Preferably, the material of the heating layer is capable of limiting the temperature below a threshold value.

[0021] Preferably, the radiant heating device comprises a radiant heat insulation layer disposed between the heating layer and the rear protective layer.

[0022] According to one feature, the radiant heating device may comprise a conductive heat insulation layer disposed behind the rear protective layer.

[0023] According to one embodiment, the removable attachment means of the removable heating system may be configured to form a ventilation gap between the radiant heating device and the support.

[0024] The invention also relates to a leg rest unit for an aircraft seat assembly, comprising a leg rest panel and at least one removable heating system as previously described.

[0025] According to an exemplary embodiment, the leg rest unit may comprise a recess for the legs of a passenger delimited by the leg rest panel and an upper panel, at least one removable heating system as previously described being arranged on the upper panel opposite the recess.

[0026] Advantageously, the leg rest unit may comprise a housing for the feet of a passenger delimited by the leg rest panel and the floor, and at least one removable heating system as previously described on a lower face of the leg rest panel arranged opposite said housing and / or on the floor opposite said housing.

[0027] Even more advantageously, the leg rest unit may comprise a front panel intended to be oriented towards a passenger and inclined downwards, the front panel comprising at least one removable heating system as previously described.

[0028] The invention also relates to an aircraft seat assembly comprising at least one heating system as previously described.

[0029] Additionally, the seat assembly may include a leg rest unit as previously described.

[0030] The invention also relates to an aircraft comprising at least one seat assembly as previously described. Brief description of the drawings

[0031] Other aims, advantages and characteristics will emerge from the description which follows, given purely for illustrative purposes and with reference to the appended drawings in which:

[0032] [Fig-1] is a sectional view of a removable heating system incorporating a radiant heating device according to one embodiment of the invention;

[0033] [Fig.2] is a sectional view of the radiant heating device of [Fig.l];

[0034] [Fig.3] is a sectional view of a removable heating system incorporating a radiant heating device according to another embodiment of the invention;

[0035] [Fig.4] is a sectional view of the radiant heating device of [Fig.3];

[0036] [Fig.5] illustrates a leg rest unit of an aircraft seat assembly according to a exemplary embodiment of the invention;

[0037] [Fig.6] illustrates a leg rest unit of an aircraft seat assembly according to a another example of embodiment of the invention.

[0038] In what follows, and unless otherwise indicated, the limits of a domain of values ​​are included in this domain, in particular in the expression “between”.

[0039] Furthermore, the expression “at least one” used in the present description is equivalent to the expression “one or more”. Detailed description of an embodiment

[0040] [Fig.l] illustrates a removable heating system 1 for aircraft according to a first embodiment.

[0041] The removable heating system 1 comprises at least one radiant heating device 2 comprising a plurality of stacked layers forming a multi-layer structure.

[0042] As can be seen in [Fig.2], the radiant heating device 2 comprises a heating or thermo-active layer 3.

[0043] The radiant heating device 2 also comprises an electrode layer 4 comprising at least one anode and one cathode.

[0044] According to an exemplary embodiment, the electrode layer 4, arranged in direct contact with the heating layer 3, can comprise several anodes and several cathodes.

[0045] The electrode layer 4 forms a conductive zone providing the interface between electrical connections connected to the radiant heating device 2, which are for example flexible PCB cables, and the heating layer 3.

[0046] The heating layer 3, crossed by an electric current conveyed by the electrode layer 4, then emits radiant heat.

[0047] Preferably, the material of the heating layer 3 is capable of limiting the temperature below a threshold value. In other words, the material of the heating layer 3 is a conductive material having the properties of a thermistor.

[0048] According to one example, the material of the heating layer 3 has a high PTC, acronym for the terms “Positive Temperature Coefficient” or a TCR, acronym for the terms “Thermal Coefficient of Resistance”.

[0049] Such a material is capable of limiting the temperature of the removable heating system 1 in the event of a fault by increasing the electrical resistance, and makes it possible to avoid the risk of burns to passengers.

[0050] For example, the material of the heating layer 3 is a carbon ink or a mixture of metals including copper.

[0051] Furthermore, the radiant heating device 2 comprises at least two protective layers, including a front protective layer 5 and a rear protective layer 6, arranged on either side of the assembly formed by the heating layer 3 and the electrode layer 4.

[0052] By front, we mean the face of the removable heating system 1 intended to be oriented towards the passenger.

[0053] Conversely, by rear is meant the face of the removable heating system 1 opposite the front face, intended to be oriented towards the support on which it is mounted.

[0054] The two front and rear protective layers 5, 6 ensure the resistance of the radiant heating device 2.

[0055] In order to meet aeronautical constraints, the material of the front and rear protective layers 5, 6 is, for example, chosen from one of the following materials: polyimide, a glass fiber reinforced epoxy resin composite known by the abbreviation FR-4 for “Flame Retardant 4”, polyethylene terephthalate known by the abbreviation PET, or a polyurethane thermoplastic known by the abbreviation TPU. These materials ensure mechanical strength of the radiant heating device 2 meeting aeronautical requirements. In particular, these materials are fire resistant and have high mechanical strength.

[0056] In addition to the radiant heating device 2, the removable heating system 1 comprises a plastic shell 7. The plastic shell 7 comprises an outer surface 7a facing the passenger and an inner surface 7b opposite the outer surface 7a. The radiant heating device 2 is fixed to the inner surface 7b of the plastic shell 7 by fixing means 8.

[0057] In the example illustrated, the front protective layer 5 of the radiant heating device 2 is directly fixed to the inner surface 7b of the plastic shell 7.

[0058] The plastic shell 7 has a sufficiently high thermal conductivity for efficient heat transfer from the removable heating system 2 to a passenger and a mechanical strength meeting aeronautical requirements including fire resistance.

[0059] Preferably, the thermal conductivity X of the plastic shell 7 is between 0.1 and 0.3W / mK.

[0060] Furthermore, the thermal inertia of the plastic shell 7, defined by the product of the thermal conductivity, the density and the specific heat capacity, allows the plastic shell 7 to reach a temperature high enough to provide thermal comfort to the passenger and low enough so that the latter can touch it without injury.

[0061] The material of the plastic shell 7 may be a thermoplastic, for example, chosen from: polyvinyl chloride (PVC), acrylic PVC or polycarbonate (PC).

[0062] In addition, the thermal conductivity of the fixing means 8 is, advantageously, sufficiently high to allow conductive heat and radiant heat to pass towards the passenger.

[0063] The thickness of the fixing means 8 is less than the thickness of the plastic shell 7 and the thickness of the radiant heating device 2.

[0064] For example, the fixing means 8 may comprise adhesive tape or glue.

[0065] According to a variant, the fixing means 8 can be configured so as to mount the radiant heating device 2 on the plastic shell 7 by simple pressure assembly.

[0066] According to one embodiment, the heating layer 3 can be arranged in a plurality of independent elements so as to make the radiant heating device 2 more flexible and allow different heating levels along the external surface of the removable heating system 1.

[0067] Preferably, the radiant heating device 2 further comprises a radiant heat insulation layer 9 disposed behind the heating layer 3 allowing the reflection of the radiant heat initially radiating in the direction away from the passenger. This makes it possible to increase the amount of radiant heat in the direction of the passenger. The radiant heat insulation layer 9 also makes it possible to increase the efficiency of radiant heat transfer and advantageously has mechanical resistance meeting aeronautical requirements including fire resistance.

[0068] In the illustrated example, the radiant heat insulation layer 9 is a metal layer disposed between the heating layer 3 and the rear protective layer 6.

[0069] A decorative layer 10 can be added to the front of the removable heating system 1 on the plastic shell 7.

[0070] In order to meet aeronautical constraints, the mechanical resistance properties of the decorative surface 10 are preferably identical to the properties of the plastic shell 7 and the fixing means 8 of the radiant heating device 2 on the plastic shell 7.

[0071] Like the plastic shell 7, the decorative surface 10 preferably has a sufficiently high thermal conductivity for efficient heat transfer from the removable heating system 2 to a passenger and a mechanical strength meeting aeronautical requirements including fire resistance.

[0072] The decorative layer 10 preferably has a thermal inertia allowing it to reach a temperature high enough to provide thermal comfort to the passenger and low enough so that the latter can touch it without injuring himself.

[0073] The thickness of the decorative layer 10 is preferably less than the thickness of the plastic shell 7.

[0074] The removable heating system 1 also comprises removable fixing means 11 of the heating system 1 on a support.

[0075] The removable nature facilitates the certification of the removable heating system 1 which can be certified independently of the support on which it is fixed. In addition, the removable nature makes it easier to maintain the removable heating system 1.

[0076] In the embodiment illustrated in [Fig.l], the removable heating system 1 is removably fixed to a composite panel 12. The composite panel 12 comprises a flat surface 12a on which the removable heating system 1 is mounted.

[0077] In the example illustrated, the removable fixing means 11 comprise at least two hooking elements or fixing clips 11a and 11b extending from the inner surface 7b of the plastic shell 7.

[0078] Advantageously, the plastic shell 7 and the removable fixing means 11 can form a single-piece structure.

[0079] According to a variant, the removable fixing means 11 may comprise self-gripping fasteners that are easily mounted and dismounted.

[0080] The radiant heating device 2 attached to the plastic shell 7 can be easily disassembled from its support by removing the plastic shell 7.

[0081] Preferably, the radiant heating device 2 comprises a conductive heat insulation layer disposed behind the rear protective layer 6.

[0082] In the embodiment of [Fig.l], the conductive heat insulation layer is a ventilation gap formed between the radiant heating device 2 and the support which, in this example, is the composite panel 12.

[0083] The removable fixing means 11 of the removable heating system 1 can be configured to form the ventilation gap 13, in particular by adjusting the dimensions of the attachment elements 11a and 11b to form spacers.

[0084] The attachment elements 11a and 11b illustrated pass through the radiant heating device 2 and fix the assembly formed by the plastic shell 7 and the radiant heating device 2 to the composite panel 12.

[0085] The width of the ventilation gap 13 is sufficiently small, preferably less than 3 mm, so that no air flow is present in the ventilation gap 13. In this way, the conductive heat insulation layer limits the amount of conductive heat in the direction away from the passenger. The conductive heat is used to increase the temperature of the plastic shell 7 and increase the amount of radiant heat toward the passenger and the efficiency of radiant heat transfer.

[0086] Preferably, the removable fixing means 11 represent less than 10% of the space of the ventilation gap 13.

[0087] Alternatively, the support may also have a shape different from a panel and be formed by a structure or a set of non-planar structures, for example formed from composite or metal.

[0088] In a second embodiment of the removable heating system referenced 14 illustrated in [Fig. 3], the removable heating system 14 is fixed on a support formed by two structures 15a and 15b. The structures 15a and 15b are not parallel to the rear protective layer 6. The free space formed between the plastic shell 7 and the structures 15a, 15b is, in the example illustrated, greater than 5 mm, outside the attachment elements 11a and 11b, so that an air flow can circulate between the radiant heating device 2 and the structures 15a, 15b. Given the circulating air flow, the free space formed does not allow a conductive heat insulation layer to be formed.

[0089] Therefore, the radiant heater 16 illustrated in [Fig.4] preferably further comprises a conductive heat insulation layer 17, disposed behind the rear protective layer 6.

[0090] The conductive heat insulation layer 17 may be an insulating foam.

[0091] Each of the attachment elements 11a and 11b is fixed to one of the structures 14a and 14b. of the support.

[0092] One or more removable heating systems 1, 14 may be removably integrated into the seat of the aircraft seat assembly such that a portion of the seat forms a support.

[0093] The presence of removable heating systems 1, 14 makes it possible to compensate for the existence of perceived cold conditions originating from the overall air conditioning of the cabin generally deliberately left at low temperatures to reduce the risk of dizziness within the aircraft cabin.

[0094] In the illustrated example, the support is a structure located on a leg rest unit 18 of a seat assembly of an aircraft cabin.

[0095] By aircraft seat assembly is meant an assembly comprising at least one aircraft cabin seat and which may comprise other structures in addition to the seat such as a leg rest unit 18.

[0096] By leg rest unit is meant an ottoman-type structure allowing a passenger sitting on a seat to raise his legs by positioning them on the leg rest unit 18. The leg rest unit 18 is therefore preferably arranged opposite the seat.

[0097] According to one embodiment, the leg rest unit 18 may be integrated into the rear portion of the seat located in front. The aircraft seat assembly may then include the front seat.

[0098] As can be seen in Figures 5 and 6, the leg rest unit 18 for an aircraft seat assembly may comprise a leg rest panel 19 on which the passenger can rest his legs and at least his feet.

[0099] The illustrated leg rest unit 18 further comprises a leg recess 20, delimited by at least one leg rest panel 19 and an upper panel 21. The illustrated leg rest panel 19 comprises an upper face 19a and a lower face (not visible) opposite the upper face 19a.

[0100] In the illustrated example, the recess 20 is also delimited by two side panels 22 and 23 so that the recess 20 and a rear panel (not visible) form a niche in the leg rest unit 18.

[0101] A housing 24 for the passenger's feet may be provided between the leg rest panel 19 and the floor, allowing the passenger to position his feet on the floor, under the leg rest panel 19.

[0102] At the top, the leg rest unit 18 may comprise a front panel facing the passenger. The front panel illustrated comprises a lower front panel 25 and an upper front panel 26.

[0103] The lower front panel 25 may advantageously be inclined downwards so as to be oriented towards the passenger's legs.

[0104] In one embodiment, the leg rest unit 18 may incorporate a screen 27, for example example in the upper part, on the upper front panel 26, above the lower front panel 25.

[0105] One or more removable heating systems 1, 14 may be removably integrated into the leg rest unit 18.

[0106] Conditioned air in the aircraft cabin may originate from high areas such as a cabin roof and an overhead luggage compartment and circulate to air outlets that may be arranged above the floor. In addition, the floor is the coldest location in the aircraft cabin, and existing heat sources such as those formed by the passengers themselves create upward heat convection. As a result, hot air is trapped in high areas and low areas such as the floor and the passenger footwell 24 remain at lower temperatures.

[0107] In addition, the parts of the passenger's body in contact with padded areas of the seat, such as insulating foams, automatically heat these padded areas, so that a feeling of cold of the passenger comes from these areas which are not in contact with the padded areas of the seat, in particular the feet, the legs and in particular the lower part of the legs, the hands and the arms.

[0108] The presence of removable heating systems 1, on the leg rest unit 18 makes it possible to reach, advantageously, the lower parts of the passenger and, preferably, the segments of the body which are not in contact with the insulating foam of the seat, so as to counter the sensation of cold perceived at the level of the lower limbs and improve the thermal comfort of the passenger.

[0109] By lower part of the body of a passenger is meant the limbs of a seated passenger located below the trunk, including the arms, hands, legs and feet.

[0110] With reference to [Fig. 5], at least one removable heating system 1, 14 may be arranged in a first zone 28, on the lower front panel 25, facing outward from the leg rest unit 18, towards the passenger. The lower front panel 25 being inclined downwards, the removable heating system 1, 14 is facing towards the lower parts of the passenger's body.

[0111] At least one removable heating system 1, 14 can also be arranged in a second zone 29, on a lower face of the leg rest panel arranged opposite the housing 24.

[0112] Preferably, as shown in [Fig.6], one or more removable heating systems 1, 14 may be arranged in a third zone 30, on the upper panel 21, opposite the recess 20.

[0113] In addition, at least one removable heating system 1, 14 can also be arranged in a fourth zone 31, on the ground, for example on the false floor of the aircraft cabin, opposite the housing 24 for the feet.

[0114] The positioning of at least one removable heating system 1, 14 in one of the first, second, third and fourth zones 28, 29, 30 and 31 makes it possible to reach the coldest parts of the passenger's body.

[0115] In order to create an enveloping heat zone, several removable heating systems 1, 14 can be arranged on the leg rest unit 18.

[0116] The removable nature of the removable heating system 1, 14 makes it easy to integrate it into the leg rest unit 18.

[0117] The removable heating system 1, 14 thus makes it possible to provide improved thermal comfort to the passenger, by non-intrusive radiant heating, combining high heat transfer efficiency, safety and compliance with aeronautical requirements.

Claims

Claims

1. Removable heating system for aircraft, comprising: - one or more radiant heating devices (2) each comprising: a heating layer (3); an electrode layer (4) comprising one or more anodes and one or more cathodes; two front and rear protective layers (5, 6) arranged on either side of the assembly formed by the heating layer (3) and the electrode layer (4); and a radiant heat insulation layer (9) arranged between the heating layer (3) and the rear protective layer (6); - a plastic shell (7) fixed on the front protective layer (5) of the radiant heating device (2); and - removable fixing means (11) of the removable heating system (1; 14) on a support (12; 15a, 15b).

2. The system of claim 1, wherein the material of the front and back protective layers (5, 6) is selected from: polyimide, FR-4 glass fiber reinforced epoxy resin composite, polyethylene terephthalate, or a polyurethane thermoplastic.

3. System according to claim 1 or 2, wherein the material of the heating layer (3) is capable of limiting the temperature below a threshold value.

4. A system according to any preceding claim, wherein the radiant heater (2) comprises a conductive heat insulation layer (13; 17) disposed behind the back protective layer (6).

5. System according to any one of the preceding claims, wherein the removable fixing means (11) of the removable heating system (1) are configured to form a ventilation gap (13) between the radiant heating device (2) and the support (12; 15a, 15b).

6. A leg rest unit for an aircraft seat assembly, comprising a leg rest panel (19) and at least one removable heating system (1; 14) according to any one of the preceding claims.

7. A leg rest unit according to claim 6, comprising a recess (20) for the legs of a passenger defined by the panel leg rest (19) and an upper panel (21), at least one removable heating system (1; 14) according to any one of claims 1 to 5 being arranged on the upper panel (21) opposite the recess (20).

8. Leg rest unit according to claim 6 or 7, comprising a housing (24) for the feet of a passenger delimited by the leg rest panel (19) and the floor, and at least one removable heating system (1; 14) according to any one of claims 1 to 5 on a lower face of the leg rest panel (19) arranged opposite said housing (24) and / or on the floor opposite said housing (24).

9. A leg rest unit according to any one of claims 6 to 8, comprising a front panel intended to be oriented towards a passenger and inclined downwards, the front panel comprising at least one removable heating system (1; 14) according to any one of claims 1 to 5.

10. Aircraft seat assembly comprising at least one heating system (1; 14) according to any one of claims 1 to 5.

11. A seating assembly according to claim 10, comprising a leg rest unit (18) according to any one of claims 6 to 9.

12. An aircraft comprising at least one seat assembly according to claim 10 or 11.

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