MX2014006503A

MX2014006503A - Wall insulation panel.

Info

Publication number: MX2014006503A
Application number: MX2014006503A
Authority: MX
Inventors: Lawrence Carbary; Robert H Bruno; Peter Everett; Matthew L Phillips
Original assignee: Dow Corning
Priority date: 2011-12-05
Filing date: 2012-12-05
Publication date: 2014-07-14
Also published as: WO2013085983A1; CN103987902A; BR112014013651A8; US20140329042A1; BR112014013651A2; EP2788555A1; KR20140107336A; CA2857595A1; JP2015505921A

Abstract

A wall insulation panel for use on a wall comprising at least the successive layers of: a first protective panel having a wall-meeting surface and a vacuum insulating panel (VIP) facing surface, an intermediate VIP panel; and a second protective panel having a VIP facing surface and an outward facing surface; characterised in that there is an expansion region between at least one of the first and second protective panels and the VIP panel to allow for expansion of the VIP panel without deformation of the outward facing surface of the second protective panel. In this way, the expansion region allows for expansion of the VIP panel without deformation of the VIP facing surface of the second panel, and thus without deformation of the outward facing surface. This maintains the integrity and aesthetic appearance of the outward facing surface, and any further surface or layer thereon, such as a rendered layer.

Description

WALL INSULATION PANEL Cross reference to related requests This application claims priority a and all the advantages of the US provisional patent application. UU no. 61 / 566,747, filed December 5, 2011, the content of which is incorporated herein by reference.

Technical field The present invention relates to a wall insulation panel for use in a wall and includes a vacuum insulation panel (VIP), as well as a wall insulation veneer comprising a series of such panels of insulation, to provide, in particular, a continuous VIP plane.

Background Vacuum insulation panels (VIP), also called, frequently, "VIP panels", are a highly efficient advanced thermal technology, which has an insulation capacity at least 3 to 7 times more effective than foams of plastic or conventional fibrous insulation. VIP panels are increasingly used to improve the performance of static items such as refrigerators, and refrigerated vehicles.

VIP panels are used or proposed to be used, increasingly, in the insulation of buildings, especially with the aim of making buildings more thermally efficient. Generally, VIP panels are more compact (being thinner) than existing insulation panels, which guarantees savings in both space and energy. The insulation inside the "cavity" walls is known, but it is also desired to improve the insulation on the exterior walls of the buildings.

Conventionally, insulation of external walls for buildings is provided by solid panels formed with traditional foam or fibrous insulation. These panels provide a robust product that is able to withstand handling during the construction and installation processes, as well as being able to be cut and shaped into any size and fixed to the wall by easy fastening methods that include nails and other fixing brackets that can pass through, intentionally or accidentally, said panels without significantly affecting their isolation properties.

After adding the insulation panels during the construction of the wall, an end layer is usually added, usually a "coated" layer to provide a smooth and uniform finish to the exterior of the building, for weather shielding, and as the final layer oriented towards the exterior that defines the "view" of the building.

VIP panels, which include a vacuum, are generally less robust, and require at least some protection during installation and fixing to withstand the handling involved. Accordingly, conventionally, VIP panels for construction purposes are completely wrapped on all sides in one or more foam protective layers to form an insulation panel.

However, said fully protected and wrapped VIP panels have two problems. In the first place, although the vacuum technology has improved, the existence of the vacuum in the VIP panels still allows the transfer of gases from the atmosphere to the interior of the panel through the membrane, that is to say, "leaks" from the vacuum. But any leakage will affect the total size of the wrapped VIP panels, by expanding the entire insulation panel and, therefore, will deform any weather shield or coated finish on it. The coating it will present cracks and allow moisture to enter, which will affect the integrity of the panel, as well as being aesthetically unpleasant.

Secondly, the total effectiveness of the vacuum insulation decreases when a number of such panels come together to form a surface or total plating: This is because the foam protection that surrounds the VIP panels on all sides, insulates the panels VIP, so that by providing a number of said panels together no continuation of the "vacuum isolation" properties of the separated VIP panels is created. Accordingly, "rapid heatways" are created, that is, more accessible rapid routes for heat displacement, which allow the passage of heat from one side of said insulation panels to the other side, generally from the outside to the inside . The hot heat tracks are formed between the VIP panels where the foam protection breaks the connection of the insulation part to the actual vacuum of each panel, despite the union of the insulation panels.

Extract of the invention An object of the present invention is to provide an improved wall insulation panel having a VIP panel for use in the wall insulation and which is able to accommodate the VIP leakage, and / or reduce the number of rapid heat pathways through a series of such panels.

In accordance with one aspect of the present invention, there is provided a wall insulation panel for use in a wall comprising at least the successive layers of: a first protection panel having a surface joining the wall and a surface facing the vacuum insulation panel (VIP), an intermediate VIP panel; Y a second protection panel having a surface oriented towards the VIP and a surface oriented towards the outside; characterized in that there is a region of expansion between at least one of the first and second protection panels and the VIP panel to allow the expansion of the VIP panel without deformation of the surface facing outwardly of the second protection panel.

In this way, the expansion region allows the expansion of the VIP panel without deformation of the surface facing the VIP of the second panel and, therefore, without deformation of the surface facing outwards. This maintains the integrity and aesthetic appearance of the surface oriented towards the outside, and any additional surface or layer thereof, such as a coated layer.

The wall insulation panel of the present invention can be used in any type, shape and extension of wall, for example, an interior wall, an exterior wall, roof, roof, floor, door or any other surface intended to provide a similar structure. , and it is not limited to these. The nature, extent, design and shape of the wall are not limiting factors for the present invention.

Preferably, the wall insulation panel can be used on the exterior wall of a building.

The typical but not limiting dimensions of the wall insulation panels can be in the range of 0.3 m to 2.5 m "width", 0.3 m to 4 m "height", and 50 to 500 mm "thickness".

The nature, size, shape and design of the first protection panel is not limiting for the present invention. Any suitable material, preferably, a durable plastic foam and, more preferably, selected from the group consisting of expanded polystyrene (EPS), can be formed.

English), extruded polystyrene (XPS), polyurethane (PU), PIR (polyisocyanurate foam), aluminum or any rigid plastic.

Similarly, the nature, size, shape and design of the second protection panel is not limiting for the same invention, and may be the same as or different from those of the first protection panel. Preferably, the second protection panel can also be formed of any suitable material, more preferably, a durable plastic foam, and even more preferably, selected from the group consisting of expanded polystyrene (EPS), extruded polystyrene (XPS) , polyurethane (PU), PIR (polyisocyanurate foam), aluminum or any rigid plastic.

The second protection panel has a surface facing outwards. The term "outwardly" is used in the present description to refer to the direction opposite to the "surface of connection with the wall", and in the same way that most of the walls of the building have a surface oriented towards the interior and an exterior surface or oriented towards the outside. Generally, the surface "outwardly" of a panel is the surface of the panel that is still visible after applying the panel to a wall.

The intermediate VIP panel can be of any suitable nature, size, shape and design so that it can be accommodated between the first and second protection panels. The VIP panel can be formed from any film, membrane, wall, cover, etc., suitable exterior generally called the "membrane material", inside which there is a vacuum. The vacuum may be any suitable pressure, generally less than the "ambient" or "atmospheric" pressure, such as less than 0.5 kPa (5 mbar) for VIP filled with fumed silica, and less than 0.1 kPa (1 mbar) for VIP full with mineral wool. The vacuum pressure can be related to the size and other construction parameters of the VIP panel.

The wall insulation panel may comprise one or more intermediate VIP panels, which may be the same or different; and having, optionally, equal or similar dimensions and other parameters, and references in the present description to the term "intermediate VIP panel" include a single intermediate VIP panel or multiple intermediate VIP panels, arranged in layers between the first and second panels of protection .

As described above, the membrane or cover material of the VIP panel is intended to withstand the transfer of gases from the atmosphere to the inside of the panel, which obviously reduces the vacuum insulation performance of the panel and also expands the size of the panel. A membrane material such as an aluminum foil has good vacuum resistance properties, in addition to being easily "sealable" during the method of manufacturing the VIP panels. One or more additional layers or covers may be inside or outside the membrane material. However, it is not possible to produce a perfect vacuum layer, especially in the vacuum pressures used to form VIP panels, and that will be subjected to the "conditions" of the walls of buildings, such as temperature variations, long exposure term, any impact, etc., as well as the achievement of the prolonged useful life of the product and the efficiency generally desired by building manufacturers.

The VIP panel may include one or more internal media. The internal media includes materials such as airgel, silica, especially fumed silica, glass fiber and glass microfiber.

In accordance with one embodiment of the present invention, VIP panel used in the present invention is a VIP panel fumed silica, available from Dow Corning Corporation of Midland, MI, USA. UU The region of expansion between at least one of the first and second protection panels and the VIP panel of the present invention allows the expansion of the VIP panel without deformation of the surface facing outwardly of the second panel. Therefore, the integrity of the surface facing outwards can be maintained. This integrity includes, but is not limited to, being a barrier against the environment, particularly the climate, as well as the aesthetic appearance of the surface facing outwards, or any additional layer or surface or material added on the surface facing outward . For example, any deformation on the surface facing outward could crack an overcoat layer on it, and allow moisture to enter with its associated problems, in addition to having a permanent unpleasant appearance.

The expansion region may comprise any area or space capable of accommodating the expansion of the vacuum insulation panel within the dimensions of the wall insulation panel, without affecting the shape or plane of the surface facing outwardly of the second protection panel. .

The region of expansion may extend, partially, substantially or completely through one or more surfaces of the VIP panel. In particular, it may be partially, substantially or completely of the same dimensions as at least one of the VIP-facing surfaces of the first and second protection panels.

In accordance with one embodiment of the present invention, the length and width of the expansion region coincides, wholly or partially, with the length and width of the VIP panel.

According to another embodiment of the present invention, the region of expansion has a completely or substantially constant depth, "depth" is the dimension extending in a transverse direction from one side of the VIP panel.

In accordance with another embodiment of the present invention, the expansion region includes a compensation layer. The compensation layer optionally comprises one or more layers and or materials, and is capable of compensating for any expansion in the size of the VIP panel.

Preferably, the compensation layer comprises one or more solid or semi-solid materials, of which at least one portion is deformable to accommodate the expansion of the VIP. Optionally, the compensation layer may be formed from one or more materials, which are the same or different, wherein at least one of said materials is deformable and at least one of said materials is not deformable due to deformation or expansion of the VIP panel.

The "different" materials of the compensation layer may include a material having the same chemical composition or material, such as one or more plastics, but having different properties, such as different density, molecular weight, etc. Plastics such as EPS are available in different densities, molecular weights, etc. to provide the same type of plastic, but with different properties, especially different mechanical properties, such as strength.

Optionally, the region of expansion is formed of one or more deformable materials as defined above, and one or more gaseous spaces or spaces, such as one or more spaces or air cavities.

The deformable materials may extend, regularly or irregularly, through the expansion region, and may extend, partially, substantially, or completely, through the expansion region.

According to another embodiment of the present invention, the expansion region or compensation layer includes one or more of the group comprising: ribs, tubes, springs and a soft and / or compressible foam, for example, a very soft foam.

Optionally, the region of expansion comprises a series of ribs or tubes extending between a surface facing the VIP and the VIP panel, wherein at least a portion of these ribs or tubes are deformable. Said ribs or tubes may be formed from a soft low density PU foam, or other soft low density foam, or a flexible foam, or flexible tubes, molded or extruded foams, or even a silicone foam or acrylic materials. . Optionally, the ribs or tubes provide a corrugated surface between the surface facing the VIP and the VIP panel. Optionally, the ribs or tubes extend from the surface facing the VIP to join with VIP panel.

In another embodiment of the present invention, the compensation layer is a laminated material shaped to fit, directly, in the expansion layer. The laminated material it may comprise a first surface having a deformable material, such as a number of ribs or corrugations extending, transversely, from the first sheet. Optionally, the sheet has a second opposing surface, which forms a "sandwich" effect between the deformable material. Said laminate material can be formed as an extruded material, and cut into the desired shape for easy insertion into the expansion region during the manufacture of the wall insulation panels. Alternatively, the compensation layer can be molded.

Preferably, the region of expansion is between the surface facing the VIP of the second panel and the VIP panel. Optionally, the expansion region is located between the VIP panel and the VIP-facing surface of the first protection panel to allow the same possibility of expansion of the VIP panel without deformation of the surface facing outwardly of the second protection panel. Alternatively, an expansion region could be located on each side of the VIP panel, capable of accommodating the expansion of the VIP panel on one or both sides of the VIP panel.

As mentioned above, VIP panels have been used, generally, only when they are completely surrounded by a or more protection layers in conventional insulation panels, for the purpose of protecting the integrity of the most fragile VIP panel during use in the construction industry, etc. However, because the protection surrounds the VIP panels on all sides, the provision of a number of said panels together to cover a wall does not allow the continuation of the "vacuum insulation" properties of the isolated VIP panels and, therefore, separated within each of the insulation panels. This means that fast heat paths are formed between the VIP panels, despite the union of the insulation panels.

Accordingly, in another embodiment of the present invention, the wall insulation panel of the present invention comprises a VIP panel extending to two opposite sides of the wall insulation panel. In this way, said sides of the VIP panel can be joined, directly, with the VIP sides of other panels placed against it, to provide a continuation of the vacuum insulation effect through two or more adjacent wall insulation panels, adjacent, joint or otherwise contiguous of the present invention. Therefore, there is no possible rapid heat path between them, and the reduction of the number of "fast heat paths" in a plating Insulated wall increases the effectiveness of the total insulation effect through a number of panels.

The term "directly joining", as used in the present description, refers to the joining or wrapping of the VIP panels so that a continuation of the vacuum insulation effect is provided. This means that, where there is some intermediate layer between the two VIP panels, this has a minimal effect on the vacuum insulation property. Preferably, the two VIP panels of this embodiment of the present invention abut without any intermediate layer.

According to another embodiment of the present invention, the surface facing the exterior of the outer panel has a finish coated thereon.

Optionally, the outer panel includes a transverse warning line parallel to the surface facing outward, to indicate a cutting zone. The cutting zones indicated in the building panels are known in the art, and generally comprise one or more lines formed by two-dimensional or three-dimensional additions or alterations, visual or formed on the surface facing outwards, to indicate a user what area of the wall insulation panel it can be cut with the purpose of forming the necessary or desired final shape of the wall insulation panel, generally, to coincide with a corresponding space in the wall, without affecting the VIP panel and, more particularly, without the need to cut through the panel VIP and, therefore, deny the effect of vacuum insulation. Such warning lines include continuous or non-continuous red lines or indented lines.

In accordance with another aspect of the present invention, a wall insulation veneer is provided comprising a series of adjoining wall panels as defined in the present disclosure. The wall insulation veneer can generally be extended in two or three dimensions, but is not limited to these, and is a flat outer wall of a building, such as a building or commercial properties.

Preferably, the wall insulation veneer of the present invention provides a continuous VIP plane in at least one dimension, based on the use of two or more adjoining wall insulation panels of the present invention, each comprising a VIP panel that It extends to two opposite sides of the wall insulation panel, to increase the effect of total vacuum insulation of the wall insulation plating.

Brief description of the figures The embodiments of the present invention will now be described only by way of example and with reference to the accompanying figures in which: Figures la and Ib are, respectively, side and perspective views of a wall insulation panel according to an embodiment of the present invention in an expanded format; Figures 2a and 2b are, respectively, side and perspective views of the wall insulation panel of Figures la and Ib in a formed format; Figure 3 is one side of the wall insulation panel of Figure 2a after the expansion of the VIP panel; Figure 4 is a schematic front view of two adjoining wall insulation panels of Figures I and 2; Y Figure 5 is a schematic perspective view of a number of adjoining wall insulation panels of Figures 1 and 2 to form a wall insulation plating in accordance with another embodiment of the present invention.

Detailed description of the invention With reference to the figures, Figures la, Ib, 2a and 2b show a wall insulation panel 2 according to an embodiment of the present invention, comprising a first protection panel 4 having a surface 6 for joining to the wall and a surface 8 facing the vacuum insulation panel (VIP), an intermediate VIP panel 10, and a second protection panel 12 having a surface 14 facing the VIP and a surface 16 facing outwards.

Figures la and Ib show the wall insulation panel 2 in an expanded form, before joining the panels in a manufacturing method to provide the formed or completed wall insulation panel 2 shown in Figures 2a and 2b.

Each of the first and second protective panels 4, 12 are made of expanded polystyrene (EPS). The EPS can be extruded, easily, in the relevant forms, or clearly. in other similar forms capable of achieving the protective effect, to surround the VIP panel 10 in a protective manner or as a clam shell.

Although the present invention is not limited to this, Figures 1 and 2 show the first protection panel 4 forming a "base channel", having a rear wall portion 18 and two protruding edge portions 19, having the Three-sided dimensions of the VIP panel 10 to accommodate and protect the VIP panel 10 on three sides. The edge portions 19 of the first protection panel 4 are further formed to accommodate the corresponding projecting upper and lower walls 20 of the second protection panel 12, which overlap when they are joined as shown in Figures 2a and 2b.

The VIP panel 10 is formed of an aluminum membrane and an internal pyrogenic silica medium, available from Dow Corning Corporation of Midland, Michigan, USA. UU While not limited to these, the dimensions of the wall insulation panel 2 could be in the range 1.5m x 1.5m x 0.5m.

The second protection panel 12 includes an expansion region 22, which when forming the insulation panel 2 of wall as shown in Figures 2a and 2b, extends between the surface 14 facing the VIP of the second protection panel 12 and the opposite surface of the VIP panel 10.

The region of. Expansion 22 includes a compensation layer formed by a series of parallel and regular ribs 24 extending from the surface 14 facing the VIP of the second protection panel 12, to provide a pattern or corrugated surface between the surface 14 facing the VIP and the VIP panel 10. The ribs 24 are formed of a suitable material such as soft PU foam of low density, which will deform / compress when a VIP panel is engaged as shown in Figure 3 and as will be described herein in ahead .

As shown in Figures 1 and 2, the ribs 24 extend, completely, from the surface 14 facing the VIP of the second protection panel 12 to join with the VIP panel 10, and the ribs 24 extend through the all of this surface 14 oriented towards the VIP.

The wall insulation panel 2 includes a transverse warning line 26 parallel to the outward facing surface 16 to indicate a cutting zone. Warning line 26 is in the form of a slot or channel along of the upper part of the second protection panel 12, and may be of a different color, such as red, compared to the color of the second protection panel 12. The warning line 26 provides an indication to the installer of the extent to which the second protection panel 12 can be cut or formed in any other way without the need to cut, again, in the VIP panel 10 and, thereby, destroy its integrity.

Figures 1 and 2 further show two vertical sides 28 of the VIP panel 10 extending to two opposite sides of the wall insulation panel 2. Said sides are not limited to being "vertical" as such, and depend on the use and installation of the wall insulation panel 2. The vertical sides 28 extend to the vertical side edges of the wall insulation panel 2, ie they have the same "length" as the first and second protective panels 4, 12.

Figure 3 shows the wall insulation panel 2 formed of Figure 2a after vacuum leakage in the VIP panel 10, which expands the size of the VIP panel 10, particularly, a front wall 30 of the VIP panel 10. The expansion of this front wall is shown in an exaggerated form for a better illustration of the benefit of the present invention.

As the front wall 30 of the VIP panel deforms outwardly, generally in a convex manner, its additional space can be accommodated by deformation, i.e., compression of the opposite ribs 24, which decreases the size of the expansion region 22a. The extension of the deformation of the front wall 30, and its proximity to the surface 14 facing the VIP of the second protection panel 12, is shown exaggeratedly in Figure 3, and the expected deformation over the lifetime of the product of the wall insulation panel 2 can be calculated, above, to leave an extensive margin of error within the expansion region to avoid any complete compression of the ribs 24 over the life of the product.

Figure 3 shows the accommodation of the expansion of the VIP panel 10 by compressing the opposite ribs 24, but without the expanded front wall 30 reaching the surface 14 facing the VIP of the second protection panel 12. Accordingly, there is no deformation of the outer-facing surface 16 of the second panel 12.

It can be seen that the expansion region 22 could be located, similarly, between the VIP panel 10 and the first protection panel 4 to allow the same possibility of expansion of the opposite wall of the VIP panel 10, still without deformation of the surface facing outwards 16 of the second protection panel 12. Alternatively, an expansion region could be located on each side of the VIP panel 10, capable of accommodating the expansion of one or both of the side walls of the VIP panel.

Figure 4 is a front view of the outward facing surfaces 16 of two wall insulation panels 2 of the present invention abutting along a vertical side 32. In this way, the vertical sides 28 of the VIP panels 10 inside each wall insulation panel 2 can adjoin, directly, to form a continuous VIP plane through the extension of the two wall insulation panels 2 and thus provide the continuation of the vacuum insulation effect of the two VIP 10 panels through the backing 32. The location of other wall insulation panels together with the two wall insulation panels 2 shown in Figure 4 could extend the continuation of the vacuum insulation effect in the same direction as through the entire length of the cover of the wall insulation panels 2.

Figure 5 shows a series of 0.91 mx 0.91 m (? 3 x 3 ') / only by way of example, of the wall insulation panels 2 located in a building wall 40 to form a wall insulation plating 42 of according to another embodiment of the present invention. The wall insulation panels 2 abut along their vertical edges in a manner shown in Figure 4, to provide a continuation of the vacuum insulation effect 34 as described above.

After the application of the wall insulation plating 42, one or more coating layers may be added through the outward facing surfaces 16 of the wall insulation panels 2, to provide a final coated surface 44. The addition of one or more coated layers provides shielding against the environment, especially the climate, in addition to providing an aesthetically pleasing final finish to the exterior of the building.

It is known that the coating is susceptible to cracking if there is any modification, particularly deformation, of the surface on which it is placed. Accordingly, the ability of the present invention to maintain the surfaces oriented toward the product throughout the useful life of the product. 16 of the wall insulation panels 2 without deformation, allows the wall insulation panels 2 to maintain the integrity and aesthetic appearance of the outward facing surfaces 16, and / or any additional surface or face thereon, such as the coated surface 44. The maintenance of the integrity of the coated surface 44 is not only aesthetically pleasing, but also avoids or minimizes the possibility of moisture entering through the coated surface 44.

Accordingly, the present invention allows the expansion of a VIP panel within a wall insulation panel, without deformation of the surface facing the exterior of the second protection panel. In this way, the present invention maintains the integrity and aesthetic appearance of the surface facing outwards, or any additional surface or layer thereon. The present invention can further provide a continuation of the vacuum insulation effect through two or more adjacent or adjoining wall insulation panels.

Claims

1. A wall insulation panel for use on a wall; the panel comprises at least the successive layers of: a first protection panel having a surface joining the wall and a surface oriented towards the vacuum insulation panel (VIP), an intermediate VIP panel; Y a second protection panel having a surface oriented towards the VIP and a surface oriented towards the outside; characterized in that there is a region of expansion between at least one of the first and second protection panels and the VIP panel to allow the expansion of the VIP panel without deformation of the surface facing outwardly of the second protection panel.

2. A panel according to claim 1, further characterized in that the expansion region includes a compensation layer.

3. A panel according to claim 2, further characterized in that the compensation layer includes one or more solid or semi-solid materials, of which at least one portion can be deformed to accommodate the expansion of the VIP panel.

4. A panel according to claim 3, further characterized in that the expansion region includes one or more of the group comprising: ribs, tubes, springs, soft low density foam, ribs or adhered tubes, ribs or extruded tubes, silicone foams .

5. A panel according to claim 4, further characterized in that the expansion region comprises a series of ribs or tubes extending between a surface facing the VIP and the VIP panel, of which at least a portion of ribs or tubes are deformable.

6. A panel according to claim 4 or claim 5, further characterized in that the ribs or tubes provide a corrugated surface between the surface facing the VIP and the VIP panel.

7. A panel according to any of claims 4 to 6, further characterized in that the ribs or tubes extend, completely or substantially, from the surface facing the VIP to be joined with the VIP panel.

8. A panel according to any preceding claim, further characterized in that the expansion region is between the VIP-facing surface of the second panel and the VIP panel.

9. A panel according to any preceding claim, further characterized in that the VIP panel extends to two opposite sides of the wall insulation panel.

10. A panel according to any preceding claim, further characterized in that the surface facing the outside of the second protection panel has a finish coated thereon.

11. A panel according to any preceding claim, further characterized in that the VIP panel is a VIP panel of fumed silica.

12. A panel according to any preceding claim, further characterized in that the second panel includes a transverse warning line parallel to the surface facing outward to indicate a cutting zone.

13. A wall insulation veneer comprising a series of adjoining wall insulation panels as defined in any of claims 1 to 12.

14. A wall insulation veneer according to claim 11, further characterized in that each of the adjoining wall insulation panels comprises a VIP panel extending to two opposite sides of the wall insulation panel, so that the plating provides a continuous VIP plane.