TEMPERATURE CONTROL DEVICE FOR AN AIRCRAFT AND METHOD FOR MANUFACTURING A TEMPERATURE CONTROL DEVICE

Description

[0001] The present approach is based on a temperature control device and a method for producing a temperature control device for an aircraft according to the class of the independent claims.

[0002] When heating elements are integrated into a composite material, the composite often consists of a carrier material, such as an FR4 plate or a plastic film made of, for example, PE, onto which a PTC material is applied. This is usually done using a screen-printing process. Optionally, a plastic film can then be glued to the PTC material, or a protective coating can be applied to protect against environmental influences. Interactions between the surrounding layers and the PTC material can lead to undesirable changes in the electrical resistance of the PTC material.

[0003] DE 10 2016 107 908 A1 discloses a heating device for an aircraft interior. The heating device comprises a mechanically resilient support structure, a mechanically resilient and heat-conducting cover structure, and a heater arranged between the support structure and the cover structure. The heater comprises a heating layer made of a resistance material with a positive temperature coefficient. The resistance material can be applied to a flexible film that is bonded to the support structure. The heater can be arranged floatingly between the cover structure and the support structure.

[0004] EP 2 291 054 A1 discloses a self-regulating heater. The heater comprises a plurality of spaced-apart PTC elements embedded in an elastic encapsulation material.

[0005] EP 2 685 784 A1 discloses a heating device in which a sliding layer can be arranged between a PTC layer and a contact electrode of the PTC layer.

[0006] DE 10 2015 007 885 A1 discloses a composite component in which a heating element embodied as a heating wire is held by a foil having through-holes. Heating results in the foil being positively bonded to a bonding layer, with the bonding layer penetrating the through-holes in the foil being bonded by a material fit and / or form fit to a cover layer on the one hand and to a core layer on the other. The heating element and foil are, for example, sewn together. Disclosure of the invention

[0007] Against this background, the approach presented here provides an improved tempering device according to claim 1 and an improved method for producing a tempering device according to claim 9. The measures listed in the dependent claims enable advantageous further developments and improvements of the device specified in the independent claim.

[0008] A temperature control device for an aircraft is presented, comprising a first layer and a second layer opposite the first layer, a heating layer disposed between the first layer and the second layer, and a separating layer disposed between the heating layer and the second layer. The separating layer is shaped to allow relative movement between the heating layer and the second layer.

[0009] The temperature control device can be installed, for example, in an aircraft. The first layer and the second layer can be aligned parallel to each other. The heating layer is implemented as a PTC thermistor. The separating layer can be shaped to mechanically decouple the heating layer and the second layer. Advantageously, the separating layer can protect the heating layer without changing the electrical resistance of the heating layer. If the second layer contains resin, for example, the separating layer can prevent the resin from adhering to the heating layer during a curing process.

[0010] According to one embodiment, the separating layer can be shaped to enable the relative movement as a shearing movement. This advantageously avoids a rigid connection between the second layer and the heating layer.

[0011] Furthermore, the release layer can be formed as a release film or as a release varnish.

[0012] A release film is easy to apply and can be realized in a known manner with at least one non-adhesive surface to enable relative movement between the heating layer and the second layer. The release coating can be made of paraffin, for example. This advantageously allows a fiber structure of the second layer to be leveled.

[0013] According to one embodiment, the separating layer, for example in the form of a separating film, can be formed from a plastic. The plastic can be, for example, perfluoroethylene propylene (FEP), FPA, or polytetrafluoroethylene (PTFE). Thus, common materials can be used for the separating film.

[0014] According to the invention, the separating layer has at least one non-stick surface. This allows, for example, the heating layer to slide along the separating layer. Additionally or alternatively, the separating layer can have a viscosity of less than 1000η. This allows the separating layer to deform to allow relative movement between the separating layer and the heating layer.

[0015] The separating layer can have a thickness of more than 0.01 mm, preferably more than 0.02 mm. Advantageously, the separating layer can thus level the structure of the fibers of the temperature control device.

[0016] Furthermore, the first layer can be formed as a carrier layer and the second layer as a protective layer and / or support layer. Conversely, the second layer can also be formed as a carrier layer and the first layer as a protective layer. A carrier layer can be a plate, for example, made of a flame-resistant material, or a film. Thus, the temperature control device can be designed to be both flexible and rigid.

[0017] According to one embodiment, at least one of the layers can be formed from resin or pre-impregnated fibers. The pre-impregnated fibers can also be referred to as prepreg, for example. Prepreg stands for "pre-impregnated" and can refer, for example, to textile fiber-matrix semi-finished products pre-impregnated with reactive resins. Thus, common composite materials can be used, and any negative interactions between the second layer and the heating layer can be avoided by the separating layer.

[0018] According to one embodiment, the heating layer can be formed from a PTC thermistor material. This advantageously ensures better electrical conductivity at low temperatures than at high temperatures. This already results in simple temperature control.

[0019] Furthermore, according to the invention, the heating layer has a plurality of through-openings, and the separating layer has a further plurality of through-openings to enable direct contact between the first layer and the second layer. The plurality of through-openings and the further plurality of through-openings can, for example, be arranged in alignment one above the other. This advantageously retains the possibility of achieving mechanical strength or preventing slippage of the individual layers. Nevertheless, relative movements between the separating layer and the heating layer can occur outside the through-openings.

[0020] According to one embodiment, the temperature control device can be designed in the form of a floor panel or a wall segment for an aircraft. This means that the temperature control device can be implemented, for example, in an aircraft, but also, for example, in a vehicle or, for example, in a floor heating system in a building. Advantageously, this can heat a surface and thus a room.

[0021] Furthermore, a method for producing a temperature control device is presented, which comprises a step of stacking a first layer, a second layer, a heating layer, and a separating layer. The heating layer is arranged between the first layer and the second layer, and the separating layer is arranged between the heating layer and the second layer. The method further comprises a step of joining the first layer, the heating layer, the separating layer, and the second layer together. The separating layer is shaped to allow relative movement between the heating layer and the second layer after joining.

[0022] In the following description of advantageous embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and having a similar effect, whereby a repeated description of these elements is omitted.

[0023] Examples of the approach presented here are shown in the drawings and explained in more detail in the following description. It shows: Fig. 1 a schematic representation of a temperature control device according to an embodiment for an aircraft; Fig. 2 a schematic cross-sectional view of a tempering device according to an embodiment; Fig. 3 a schematic cross-sectional view of a temperature control device according to an embodiment; and Fig. 4 a flowchart of a method for producing a temperature control device according to an embodiment.

[0024] Fig. 1 shows a schematic representation of a temperature control device 100 according to an exemplary embodiment. For example, the temperature control device 100 is used in the interior of an aircraft 102. The temperature control device 100 is formed, for example, as a wall segment or a floor plate of the aircraft 102 and can also be used as a heater.

[0025] The temperature control device 100 has a first layer 104 and a second layer 106 opposite the first layer 104, which according to this exemplary embodiment are formed from pre-impregnated fibers or resin. The first layer 104 is formed, for example, as a carrier layer. The second layer 106 is formed, for example, as a protective layer. Alternatively, the first layer 104 is implemented as a protective layer and the second layer 106 as a carrier layer. Furthermore, the temperature control device 100 has a heating layer 108, which can also be referred to as a heating element or PTC heating element. The heating layer 108 is implemented as a PTC thermistor according to this exemplary embodiment. This enables good electrical conductivity at low temperatures. The heating layer 108 is arranged between the first layer 104 and the second layer 106.Furthermore, the temperature control device 100 has a separating layer 110 arranged between the heating layer 108 and the second layer 106. According to this exemplary embodiment, the layers 104, 106, the heating layer 108, and the separating layer 110 are aligned parallel to one another, so that the temperature control device 100 according to this exemplary embodiment is formed as a stack-like composite. The separating layer 110 is shaped to enable a relative movement, for example a shearing movement, between the heating layer 108 and the second layer 106. The separating layer 110 is formed, for example, as a separating film or a separating lacquer. According to this exemplary embodiment, the separating layer 110 has a thickness that is, for example, between 0.02 mm and 0.04 mm. According to one exemplary embodiment, the separating layer 110 has a thickness of at least 0.025 mm.

[0026] According to one embodiment, the temperature control device 100 is designed as a composite component, which can be used, for example, in lightweight constructions. A decoupling of the layers 104, 106, here in particular the second layer 106, from the heating layer 108 is achieved.

[0027] According to this embodiment, the separating layer 110, also referred to as a plastic film, has a mandatory mechanical separating effect. It neither adheres to the heating layer 108 nor adheres to any of the layers 104, 106, which may be formed from resin, thus preventing an (inseparable) bond between the resin and the heating layer 108.

[0028] In summary, the approach presented here does not create a mechanical connection between the second layer 106 and the heating layer 108. As a result, according to this exemplary embodiment, no mechanical stresses resulting from thermal expansion are transferred to the heating layer 108. Furthermore, a chemical influence of the second layer 106 on the heating layer 108 can be prevented. Furthermore, the separating layer 110 mitigates the strong pressure exerted by a glass or aramid fiber structure on the heating layer 108, for example, if the second layer 106 has such a structure. This consequently results in greater process reliability during production, for example, as well as greater resistance to very high ambient temperatures.

[0029] The advantages achievable with the presented approach are that the separating layer 110 prevents altered properties of the PTC material, such as increased electrical resistance. Possibilities for adhesion to the PTC material of the heating layer 108 can also be avoided. The approach presented here therefore presents a possibility for establishing a separating connection to the heating layer 108. The approach presented here also advantageously prevents a fabric structure from being pressed into the possibly soft PTC material of the heating layer 108 and a resulting change in the electrical resistance during a curing process, thus enabling a constant electrical resistance and preventing a change in the length of the PTC heating element of the heating layer 108.This also prevents a permanent increase in electrical resistance caused by high ambient temperatures, for example, above 85°C above a PTC cut-off point (approximately 65°C). Advantageously, a constant heating output can be achieved. Furthermore, mechanical stresses caused by thermal expansion can be avoided, and resistance to very high ambient temperatures is increased.

[0030] According to this embodiment, the heating layer 108 is connected to a voltage source 116 via a first interface 112 and a second interface 114, for example, via a first line 118 and a second line 120. This allows a current to be passed through the heating layer 108 to convert electrical energy into thermal energy. According to one embodiment, the voltage source is configured to provide a constant voltage U. The following applies to the heating power P: P = U * I

[0031] From the relationship U=R*I we get: P = U 2 / R

[0032] Here, I represents the current flow through the heating layer 108 and R represents the electrical resistance of the heating layer 108.

[0033] According to an alternative embodiment, the separating layer 110 is arranged between the first layer 104 and the heating layer 108, or a further separating layer 110 or another type of protective layer is arranged between the first layer 104 and the heating layer 108. If the temperature control device 100 has a composite structure, the separating layer 110 or optionally two separating layers 100 decouple the resin of the prepreg layers, here layers 104, 106, of the composite structure from the PTC material of the heating element of the heating layer 108.

[0034] Fig. 2 shows a schematic cross-sectional view of a temperature control device 100 according to an embodiment. The temperature control device 100 shown here can correspond to the temperature control device 100 as described in one of the Figuren 1 or 2 was described.

[0035] Shown is a schematic layer structure of the heating layer 108 in the form of a PTC heating element between the two layers 104, 106. The two layers 104, 106 can be prepreg layers or resin into which the PTC heating element is embedded. The separating layer 110 is implemented as a separating film or separating varnish.

[0036] According to one embodiment, composite release films without an adhesive coating, such as FEP, FPA, or PTFE, can be used as the release layer 110. Alternatively, the release layer 110 is implemented as a release varnish, which can also be referred to as an anti-adhesion varnish. The release varnish is, for example, a paraffin film, which, according to this embodiment, permanently separates the second layer 106 from the heating layer 108. According to an alternative embodiment, the release varnish is applied using a screen printing process.

[0037] Fig. 3 shows a schematic cross-sectional view of a temperature control device 100 according to an embodiment. The temperature control device 100 shown here can be Fig. 2 described temperature control device 100. Only the heating layer 108 and the separating layer 110 differ in that, according to this exemplary embodiment, they are not continuous, but have a further plurality of through-openings 301, 302. According to this exemplary embodiment, this serves to establish direct contact between the first layer 104 and the second layer 106. According to this exemplary embodiment, the further plurality of through-openings 302 of the separating layer 110 are located opposite the plurality of through-openings 301 of the heating layer 108. Alternatively, the heating layer 108 and the separating layer 110 each have only one through-opening 301, 302. If at least one of the layers 104, 106 comprises resin, a rigid connection between the layers 104, 106 can be created through the at least one through-opening 301, 302 when the resin cures.

[0038] According to one embodiment, the separating layer 110 is perforated when the heating layer 108 is also perforated, in order to achieve mechanical strength in the component. This avoids a problem with a non-perforated heating layer 108, which could split the temperature control device 100 into two halves and thus reduce its strength.

[0039] Fig. 4 shows a flowchart of a method 400 for manufacturing a temperature control device according to an exemplary embodiment. This means that the method 400 can be used to manufacture a temperature control device as described in Figures 1 to 3.

[0040] The method 400 comprises a stacking step 402 and a joining step 404. In step 402 of stacking, the first layer, the second layer, the heating layer, and the separating layer are stacked. The heating layer is arranged between the first layer and the second layer, and the separating layer is arranged between the heating layer and the second layer. In step 404 of joining, the first layer, the heating layer, the separating layer, and the second layer are joined together. The separating layer is selected such that, after joining, it allows relative movement between the heating layer and the second layer.

[0041] If an embodiment includes an "and / or" link between a first feature and a second feature, this should be read as meaning that the embodiment according to one embodiment has both the first feature and the second feature and according to another embodiment has either only the first feature or only the second feature.

Claims

1. Temperature control device (100) for an aircraft (102), wherein the temperature control device (100) comprises: a first layer (104) and a second layer (106) opposite the first layer (104); a heating layer (108) formed from a cold conductor material and arranged between the first layer (104) and the second layer (106); and a separating layer (110) arranged between the heating layer (108) and the second layer (106), wherein the separating layer (110) is formed to allow relative movement between the heating layer (108) and the second layer (106), characterised in that the separating layer (110) has at least one non-adhesive surface to allow the heating layer (108) to slide along the separating layer (110), and the heating layer (108) has a plurality of through openings (301), and the separating layer (110) has a further plurality of through openings (302) to establish direct contact between the first layer (104) and the second layer (106), wherein relative movements between the separating layer (110) and the heating layer (108) can take place outside the through openings (301, 302).

2. Temperature control device (100) according to claim 1, wherein the separating layer (110) is shaped to allow the relative movement as a shearing movement.

3. Temperature control device (100) according to one of the preceding claims, wherein the separating layer (110) is formed as a separating film or as a separating lacquer.

4. Temperature control device (100) according to one of the preceding claims, wherein the separating layer (110) has a thickness of more than 0.01 mm, preferably more than 0.02 mm.

5. Temperature control device (100) according to one of the preceding claims, wherein the first layer (104) is formed as a carrier layer and the second layer (106) is formed as a protective layer and / or carrier layer.

6. Temperature control device (100) according to one of the preceding claims, wherein at least one of the layers (104, 106) is formed from resin or from pre-impregnated fibres.

7. Temperature control device (100) according to one of the preceding claims, wherein the heating layer (108) is formed from a cold conductor material.

8. Temperature control device (100) according to one of the preceding claims, wherein the temperature control device (100) is formed in the shape of a floor panel or a wall segment for an aircraft (102).

9. Method (400) for manufacturing a temperature control device (100) according to one of the preceding claims, wherein the method (400) comprises the steps of: stacking (402) a first layer (104), a second layer (106), a heating layer (108) and a separating layer (110), wherein the heating layer (108) is formed from a PTC material and is arranged between the first layer (104) and the second layer (106), and the separating layer (110) is arranged between the heating layer (108) and the second layer (106); and joining (404) the first layer (104), the heating layer (108), the separating layer (110) and the second layer (106), wherein the separating layer (110) is formed to allow relative movement between the heating layer (108) and the second layer (106) after joining (106) after assembly, characterised in that the separating layer (110) has at least one non-adhesive surface to allow the heating layer (108) to slide along the separating layer (110) after assembly, and the heating layer (108) has a plurality of through openings (301), and the separating layer (110) has a further plurality of through openings (302) to establish direct contact between the first layer (104) and the second layer (106), wherein, after joining, relative movements between the separating layer (110) and the heating layer (108) can take place outside the through openings (301, 302).