WO2024136740A1

WO2024136740A1 - An end piece for a panel

Info

Publication number: WO2024136740A1
Application number: PCT/SE2023/051283
Authority: WO
Inventors: Lars Westerlind; Taisto NYSTRÖM
Original assignee: Heat Click Company Ab
Priority date: 2022-12-21
Filing date: 2023-12-19
Publication date: 2024-06-27

Abstract

The invention relates to an end piece (200) for providing electricity to a panel (100). The end piece (200) comprises a coupling means (210) for mechanically coupling the end piece (200) the panel (100) and a side connector (220) for 5 electrically connecting the end piece (200) to the panel (100). The end piece (200) further comprises a first end connector (230) and a second end connector (232) electrically connected to each other and to the side connector (220). The first end connector (230) of the end piece (200) is arranged 10 to be electrically connected to a second end connector (232´) of an adjacent end piece (200´), when the panel (100) to which the end piece (200) has been mechanically coupled and electrically connected is mechanically coupled to an adjacent panel (100´) to which an adjacent end piece (200´) has been 15 mechanically coupled and electrically connected.

Description

AN END PIECE FOR A PANEL Field of invention The invention relates to an end piece for providing electricity to a panel with e.g. a heat providing layer. Background of invention The following background information is a description of the background of the invention, which thus not necessarily has to be a description of prior art. In many parts of the world, houses, apartments, offices, shops, factories and/or other public or non-public spaces need to be heated to provide an acceptable environment for people spending time in these spaces. Such heating should provide a comfortable temperature while keeping the energy consumption to a minimum. Underfloor heating is one way to efficiently heat a space and provide an acceptable temperature with low energy consumption. It is nowadays common to install underfloor heating using warm water or electricity as a heat source when stone and/or ceramic tiles are used for covering the floor. But underfloor heating may also be used for other types of floors such as e.g. laminate floors and wooden floors. Traditionally, the heat used for providing the underfloor heating has been generated by warm water flowing in pipes/tubes under the floorboards and/or by electricity flowing through resistance in sheet materials arranged under the floorboards. Floorboards provided with an embedded heating foil generating heat when being supplied with electrical energy has also been proposed. With the heating foil embedded in the floorboard, the generated heat is much more efficiently provided to the space to be heated, since the heat is generated closer to the space to be heated, i.e. within the actual floorboard, instead of underneath it. SUMMARY OF INVENTION A floorboard with an embedded heating foil has, however, a number of problems related to providing electricity to the heating foil in the floorboard. Electrical connecting means are needed to electrically connect the floorboards to a power supply. The electrical connecting means may e.g. be arranged at an end of a row of floorboards and arranged to provide electricity to the row of floorboards. The electrical connecting means have to be robust as the floorboards will move when a person walks on the floorboards. These movements can put a lot of strain on the electrical connecting means which can becoming worn out after some use and lead to a loss of contact disrupting the heating function or even a short circuit. These possible problems may shorten the expected lifetime of the floor and even be hazardous. Floorboards requiring electricity may also lead to problems related to the installation of the floorboards including electrically connecting the floorboards to a power supply. The installation of the floor may e.g. require additional steps for electrically connecting the floorboards and/or expert skills. There may also be a risk of getting an electrical shock when connecting the floorboards. The installation of floorboards with embedded heating foils can hence be time- consuming and costly, as well as hazardous. It is therefore an objective of the invention to provide an end piece for a panel that solve at least some of the above stated problems and/or disadvantages. Another objective of the invention is to provide an end piece which is safe to handle from an electrical point of view and easy to electrically connect to adjacent end pieces. According to an embodiment of the invention, the above mentioned and other objectives are achieved with the end piece for providing electricity to a panel according to claim 1. The end piece has a first longitudinal side and an opposite second longitudinal side extending between a first end and an opposite second end, the end piece comprises: - a coupling means arranged at the first longitudinal side of the end piece for mechanically coupling the end piece to an end side of the panel, - a side connector arranged at the first longitudinal side of the end piece for electrically connecting the end piece to the panel, and - a first end connector arranged at the first end of the end piece and a second end connector arranged at the second end of the end piece, the first end connector and the second end connector being electrically connected to each other and to the side connector; wherein - the first end connector of the end piece is arranged to be electrically connected to a second end connector of an adjacent end piece when a longitudinal side of the panel, to which the end piece has been mechanically coupled and electrically connected, is mechanically coupled to a longitudinal side of an adjacent panel, to which the adjacent end piece has been mechanically coupled and electrically connected. An advantage of the end piece according to the invention is that the end piece can easily and safely be electrically connected to a panel, as well as adjacent end pieces. The end piece can be automatically electrically connected to an adjacent end piece during the mechanical coupling of the panel and the adjacent panel to each other. The panels can thereby be installed, e.g. on a floor, and electrically connected via the end pieces without any expert skills or any additional installation steps. The end piece according to the invention can provide a reliable and secure electrical contact from a panel to which it is connected to an adjacent panel, via the adjacent end piece connected to the adjacent panel. Hereby, electrical energy e.g. for generating heat in the panels can reliably flow between the panels. By usage of the end piece according to the invention, a secure and reliable power supply to the panel can further be assured. According to an embodiment of the invention, when the first end connector of the end piece has been electrically connected to the second end connector of the adjacent end piece, a heat providing layer of the panel is electrically connected to a heat providing layer of the adjacent panel. An advantage of this embodiment is that the end pieces provide a reliable and secure electrical connection between the panels, allowing electrical energy for generating heat in the panels to flow between the panels. According to an embodiment of the invention, the first end connector comprises a conductor part arranged to be rotated into a complementary conductor part of the second end connector during the mechanical coupling of the panel to the adjacent panel. An advantage of this embodiment is that the end connectors can be reliably and automatically electrically connected during the mechanical coupling of the panels to each other, without any additional connection steps. According to an embodiment of the invention, the first end connector comprises a protrusion and the second end connector comprises a complementary recess. An advantage of this embodiment is that the end connectors can be reliable connected to each other and properly aligned during the connection. According to an embodiment of the invention, the protrusion and the complementary recess extend in an extension of the first longitudinal side of the end piece or the second longitudinal side of the end piece. An advantage of this embodiment is that either side of the end connectors can be used to properly align the end connectors. According to an embodiment of the invention, the protrusion extends further in the extension of the second longitudinal side of the end piece than a conductor part of the first end connector. An advantage of this embodiment is that the protrusion may protect the conductor part, e.g. prevent male conductor part from being bent. According to an embodiment of the invention, one or more of the coupling means and the side connector comprises a self- locking member. An advantage of this embodiment is that a stable and secure mechanical coupling can be provided between the end piece and the panel. According to an embodiment of the invention, the coupling means comprises the side connector or vice versa. An advantage of this embodiment is that the mechanical coupling and electrical connection between the end piece and the panel can be integrated, reducing the complexity of the end piece and simplifying mounting of the end piece to the panel. According to an embodiment of the invention, one or more of the coupling means and the side connector is arranged to be inserted into one or more longitudinal grooves arranged in the panel. An advantage of this embodiment is that the coupling means and/or the side connector can be arranged at well- defined positions at the end piece matching the positions of the longitudinal grooves in the panel. The end piece can thereby be aligned with the panel in a simple way and can be mechanically coupled and electrically connected to a panel which has been cut. According to an embodiment of the invention, the end piece is non-conductive and encapsulates the electrical connections between the side connector, the first end connector and the second end connector. An advantage of this embodiment is that the end piece is safe to handle from an electrical point of view. According to an embodiment of the invention, the end piece comprises a displacement means arranged to displace a conductor part of the first end connector outward from the first end connector of the end piece, when the end piece is folded down onto a surface. An advantage of this embodiment is that a solid electrical connection can be provided between end connectors, while keeping the dimensions of the end connectors small. The end pieces can thereby be made thin. According to an embodiment of the invention, the displacement means comprises an elongated element attached to the conductor part of the first end connector, the elongated element comprising a joint at least partly protruding from a bottom of the end piece, in a relaxed state. An advantage of this embodiment is a simple and robust implementation of the displacement means which can provide an automatic connection of end pieces to each other. According to an embodiment of the invention, the joint is pushed into the end piece, when the end piece is folded down onto the surface. An advantage of this embodiment is that the displacement can be triggered when the end piece is connected to an adjacent end piece. A solid electrical connection between end connectors can thereby be provided automatically during the connection, without any additional connection steps. Detailed exemplary embodiments and advantages of the end piece according to the invention is hereafter described with reference to the appended drawings illustrating some preferred embodiments. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention are described in more detail with reference to attached drawings illustrating examples of embodi- ments of the invention in which: - Figs. 1a-b show schematic views of an end piece connected to a panel according to an embodiment of the invention, - Figs. 2a-b show schematic views of an end piece according to an embodiment of the invention, - Figs. 3a-b show schematic views of a first end and a second end of an end piece according to an embodiment of the invention, - Figs. 4a-b show schematic views of conductive tongues of a side connector according to embodiments of the invention, - Fig. 5 shows a schematic view of an end piece and a panel according to an embodiment of the invention, - Figs. 6a-b show schematic views of the coupling of a panel with an end piece to an adjacent panel with an adjacent end piece according to an embodiment of the invention, - Figs. 7a-b show schematic views of a first end and a second end of an end piece according to an embodiment of the invention, and - Figs. 8a-b show schematic views of an end piece with a displacement means according to an embodiment of the invention. DETAILED DESCRIPTION OF INVENTION Figs. 1 to 8 schematically show views of an end piece 200 according to various embodiments of the invention. The end piece 200 is arranged to provide electricity to a panel 100 such as e.g. a panel for a floor, a wall or a ceiling. The provided electricity may be used to generate heat in a heat providing layer of the panel 100 but may also be used for other types of power consumers in the panel 100 or may be fed through the panel 100 to an adjacent panel 100´ or another power consumer. Figs. 1a-b show the end piece 200 according to an embodiment of the invention. The end piece 200 has been mechanically coupled to an end side 104 of the panel 100 and electrically connected to the panel 100. The panel 100 may comprise longitudinal coupling means 106, 107 arranged at a first longitudinal side 116 and an opposite second longitudinal side 117, respectively. The longitudinal coupling means 106, 107 may be used to mechanically couple the panel 100 to an adjacent panel 100´. With reference to Figs. 2a-b, the end piece 200 has a first longitudinal side 202 and an opposite second longitudinal side 204 extending between a first end 206 and an opposite second end 208. The end piece 200 comprises a coupling means 210 and a side connector 220 arranged at the first longitudinal side 202 of the end piece 200. The longitudinal sides 202, 204 of the end piece 200 may have approximately the same length as the end side 104 of the panel 100, i.e. the end piece 200 may extend from the first longitudinal side 116 to the opposite second longitudinal side 117 of the panel 100, when mounted to the panel 100, as shown in Figs 1a-b. The coupling means 210 is arranged to mechanically couple the end piece 200 to the end side 104 of the panel 100. The coupling means 210 may comprise one or more coupling members arranged to engage with complementary coupling members arranged at the end side 104 of the panel 100. In the shown embodiment, the coupling means 210 comprises three male coupling members but any type of coupling member and any number of coupling member may be used. The side connector 220 is arranged to electrically connect the end piece 200 to the panel 100, e.g. to a heat providing layer of the panel 100. The side connector 220 may comprise one or more conductive members arranged to engage with complementary conductive members arranged at the end side 104 of the panel 100. In the shown embodiment, the side connector 220 comprises two conductive tongues 222 but any type of conductive members and any number of conductive members may be used. In embodiments, the coupling means 210 may comprise the side connector 220 or vice versa. The coupling means 210 and the side connector 220 may hence be integrated and/or co-located, as shown in Figs. 2a-b, where a respective conductive tongue 222 of the side connector 220 is arranged together with a respective coupling member of the coupling means 210 at two of the three coupling members of the coupling means 210. With reference to Figs. 2a-b, the end piece 200 further comprises a first end connector 230 arranged at the first end 206 of the end piece 200 and a second end connector 232 arranged at the second end 208 of the end piece 200. The first end connector 230 and the second end connector 232 are electrically connected to each other and to the side connector 220. The end piece 200 may be non-conductive and encapsulate the electrical connections between the side connector 220, the first end connector 230 and the second end connector 232. The end piece 200 may e.g. comprise a non-conductive cover/housing arranged to cover the conductive parts of the end piece 200, i.e. the electrical connections and/or connectors. The end piece 200 may further comprise a non-conductive material in which the conductive parts of the end piece 200 are embedded. The first end connector 230 of the end piece 200 is arranged to be electrically connected to a second end connector 232´ of an adjacent end piece 200´, when the panel 100 to which the end piece 200 is connected is mechanically coupled to an adjacent panel 100´ to which the adjacent end piece 200´ is connected. When the first end connector 230 of the end piece 200 has been electrically connected to the second end connector 232´ of the adjacent end piece 200´, the panel 100 is electrically connected to the adjacent panel 100 through the end piece 200 and the adjacent end piece 200´. For example, a heat providing layer in the panel 100 may be connected to a heat providing layer in the adjacent panel 100´. Figs. 3a-b show the first end connector 230 and the second end connector 232, respectively, in more detail. In the shown embodiment, a conductor part 231 of the first end connector 230 comprises two male conductors and the conductor part 233 of the second end connector 232 comprises two female conductors. However, the conductor part 231 of the first end connector 230 may, in another embodiment, instead comprise one or more female conductors and the conductor part 233 of the second end connector 232 may comprise one or more male conductors. With reference to Figs. 3a-b, the side connector 220 may have a male conductor part and comprise a conductive tongue 222. The conductive tongue 222 may be integrated with a coupling member of the coupling means 210 and at least partly provide the mechanical coupling between the end piece 200 and the panel 100. In embodiments, the coupling means 210 and/or the side connector 220 may comprise a self-locking member 212, i.e. a member which automatically fixes itself in place. In other words, the self-locking member 212 may mechanically lock the end piece 200 to the panel 100 once they have been mechanically coupled. In this way, the end piece 200 can be fixedly attached to the panel 100 by the coupling means 210 and/or the side connector 220. The self-locking member 212 may e.g. be a hook, a barb or a lip arranged to be inserted into the panel 100. In embodiments, the conductive tongue 222 of the side connector 220 may form the self-locking member 212 by having an end 222a formed into a hook, as shown in Figs. 3a-b. Figs. 4a-b show two further non-limiting examples of shapes into which the end 222a of the conductive tongue 222 may be formed to provide the self-locking function. In Fig. 4a, the end 222a of the conductive tongue 222 is formed into a double- sided hook with two flaps/lips bent downwards and one flap/lip bent upwards. In Fig. 4b, the end 222a of the conductive tongue 222 is formed into a flap/lip bent downwards through a hole in the conductive tongue 222. The coupling means 210 and/or the side connector 220 may be arranged to be placed in/inserted into one or more longitudinal grooves 121 arranged in a base layer 101 of the panel 100, when the end piece 200 is mechanically coupled to the panel 100. Fig. 5 shows an embodiment where two coupling members of the coupling means 210 are arranged in a respective longitudinal groove 121 and the conductive tongue 222 of the side connector 220 is arranged together with one of the coupling members in one of the longitudinal grooves 121. In Fig. 5, a section of a covering layer 103 and of a heat providing layer of the panel 100 has been partly removed to show the longitudinal grooves 121 in the base layer 101. The longitudinal grooves 121 may be arranged in the base layer 101 and face a heat providing layer, i.e. the opening/aperture of the grooves may be directed towards the heat providing layer. The heat providing layer is not shown in Fig. 5 but may be arranged between the covering layer 103 and the base layer 101 and at least partly above the longitudinal grooves 121. Thus, when the side connector 220 is inserted into one or more of the longitudinal grooves 121, the side connector 220 may be directly or indirectly electrically connected to the heat providing layer of the panel 100. The longitudinal grooves 121 may e.g. comprise and/or face wiring paths/conductors for the heat providing layer of the panel 100 and the side connector 220 may be electrically connected to these wiring paths. The longitudinal grooves 121 may extend from the first end side 104 to an opposite second end side of the panel 100. The longitudinal grooves 121 may have well-defined positions at the first end side 104. The coupling means 210 and/or the side connector 220 may be arranged at positions at the first longitudinal side 202 of the end piece 200 matching the positions of the longitudinal grooves 121 to align the end piece 200 with the panel 100. The longitudinal grooves 121 may further be parallel to the longitudinal side 116 of the panel 100. The end piece 200 may in this case be mechanically coupled and electrically connected to an end of the panel 100 even if the panel has been cut, i.e. made shorter. The end piece 200 is arranged to be electrically connected to an adjacent end piece 200´ during the mechanical coupling of the panel 100 to an adjacent panel 100´, as will now be described with reference to Figs. 6a-b. In the embodiment shown in Figs. 6a-b, the panel 100 is mechanical coupled to the adjacent panel 100´ by coupling means 107 arranged at the longitudinal side 117 of the panel 100 engaging with coupling means 106´ arranged at the longitudinal side 116´ of the adjacent panel 100´. Fig. 6a shows an intermediate state of the mechanical coupling. The end piece 200 has been mechanically coupled and electrically connected to the panel 100 and the adjacent end piece 200´ has been mechanically coupled and electrically connected to the adjacent panel 100´. The panel 100 is tilted, i.e. arranged at an angle, in relation to the adjacent panel 100´, with the longitudinal side 117 of the panel 100 placed adjacent to the longitudinal side 116´ of the adjacent panel 100´ and with the first end connector 230 of the end piece 200 aligned with the second end connector 232´ of the adjacent end piece 200´. The first end connector 230 and the second end connector 232´ may be aligned using complementary protrusions and recesses, as will be further described below with reference to Figs. 7a-b. As the panel 100 and hence also the end piece 200 is tilted in relation to the adjacent panel 100´ and adjacent end piece 200´, the conductor part 231 of first end connector 230 are above the complementary conductor part 233´ of the second end connector 232´, as shown in the cut-out view in Fig. 6a. During the mechanical coupling of the panel 100 to the adjacent panel 100´, the conductor part 231 of the first end connector 230 may be rotated into the complementary conductor part 233´ of the second end connector 232´. In the shown embodiment, male conductors of the conductor part 231 are rotated into female conductors of the complementary conductor part 233´, as the panel 100 is rotated/folded in relation to the adjacent panel 100´ during the mechanical coupling. Fig. 6b shows a final state of the mechanical coupling. The panel 100 has been mechanically coupled the adjacent panel 100´ by the coupling means 107, 106´. The conductor part 231 of the first end connector 230 has been inserted into the complementary conductor part 233´ of the second end connector 232´, i.e. the first end connector 230 of the end piece 200 has been electrically connected to the second end connector 232´ of the adjacent end piece 200´. In embodiments, the first end connector 230 comprises protrusions for aligning the first end connector 230 of the end piece 200 with the second end connector 232´ of the adjacent end piece 200´ and/or for protecting the conductor part 231 of the first end connector 230. With reference to Figs. 7a-b, the first end connector 230 may comprise a first protrusion 236 arranged to engage with a complementary first recess 237´ comprised in the second end connector 232´ of the adjacent end piece 200´. The first protrusion 236 protrudes in an extension of the first longitudinal side 202 of the end piece 200. If the end piece 200 and the panel 100 is moved laterally relative to the adjacent end piece 200´ and the adjacent panel 100´ during the mechanical coupling, when the panel 100 is tilted relative to the adjacent panel 100´, the first protrusion 236 of the first end connector 230 engages with the first recess 237´ of the second end connector 232´ and prevents the first end connector 230 to move past the second end connector 232´, i.e. prevents further lateral movement. Thus, the first protrusion 236 of the first end connector 230 and the first recess 237´ of the second end connector 232´ interact to align the first end connector 230 with the second end connector 232´ during the mechanical coupling of the panel 100 to the adjacent panel 100´. The first end connector 230 may further comprise a second protrusion 238 arranged to engage with a complementary second recess 239´ comprised in the second end connector 232´ of the adjacent end piece 200´. In the shown embodiment, the second protrusion 238 protrudes in an extension of the second longitudinal side 204 of the end piece 200. In a similar way to the first protrusion 237, the second protrusion 238 of the first end connector 230 may engage with the second recess 239´ of the second end connector 232´ to align the first end connector 230 and the second end connector 232´ during the mechanical coupling of the panel 100 to the adjacent panel 100´ and prevent lateral movement between the first end connector 230 and the second end connector 232´. Furthermore, the second protrusion 238 may extend further in the extension of the second longitudinal side 204 of the end piece 200 than the conductor part 231 of the first end connector 230, as shown in Figs. 2a and 7a. The conductor part 231 of the first end connector 230 may in this way be protected by the second protrusion 238. The second protrusion 238 may e.g. act as a stop preventing the panel 100 to be mechanically coupled to the adjacent panel 100´, if the second protrusion 238 is not aligned with the second recess 239´ of the second end connector 232´, i.e. if the conductor part 231 of the first end connector 230 is not aligned with the complementary conductor part 233´ of the second end connector 230´. In embodiments, the second protrusion 238 may not be arranged at the side of the first end connector 230 but instead in the first end connector, e.g. be arranged between two male conductors of the first end connector 230 and extend further out from the first end connector 230 than the two male conductors. According to an embodiment of the invention the end piece 200 comprises a displacement means 240 arranged to displace the conductor part 231 of the first end connector 230 in relation to the first end connector 230 and hence the first end 206 of the end piece 200. The conductor part 231 may hence be movably connected to the first end connector 230 in embodiments. Figs. 8a-b show the displacement means 240 according to an embodiment of the invention. The displacement means 240 is arranged to displace the conductor part 231 of the first end connector 230 outward from the first end connector 230 of the end piece 200, when the end piece 200 is folded down onto a surface. In the embodiment shown in Figs. 8a-b, the conductor part 231 of the first end connector 230 comprises two male conductors, one arranged above the other relative to a bottom 201 of the end piece 200. However, other configurations of the conductor part 231 are also within the scope of the invention. The displacement means 240 may be arranged to displace the conductor part 231 of the first end connector 230 in a longitudinal direction D1 of the end piece 200, i.e. in a direction parallel to an extension of the longitudinal sides 202, 204 of the end piece 200. When the end piece 200 is placed on a surface such as e.g., a floor, the longitudinal direction D1 may be a horizontal direction. The displacement of the conductor part 231 by the displacement means 240 may hence be a linear displacement along the extension of the end piece 200. However, the displacement means 240 may further be arranged to displace the conductor part 231 of the first end connector 230 in other directions such that the conductor part 231 is not only displace linearly but also at least partly rotated or pivoted. The displacement means 240 comprises an elongated element 244 connected to the conductor part 231 of the first end connector 230. A first end portion 242 of the elongated element 244 may be connected to the conductor part 231 e.g. by abutting or engaging with the conductor part 231 or may be attached to the conductor part 231. The elongated element 244 may comprise a joint 246 at least partly protruding from a bottom 201 of the end piece 200, in a relaxed state, i.e. when the end piece 200 is not coupled to the panel 100 and/or not placed on a surface, as shown in Fig. 8a. When the end piece 200 is folded down onto the surface the joint 246 is pushed into the end piece 200, thereby extending the elongated element 244 in the longitudinal direction D1 which in turn displaces the conductor part 231 outward from the first end connector 230, as shown in Fig. 8b. When the end piece 200 is folded down onto a surface during a mechanical coupling such as the one shown in Figs. 6a-b, the displacement of the conductor part 231 outward from the first end connector 230 causes the conductor part 231 to be inserted into the conductor part 233´ of the second end connector 232´. Thus, the first end connector 230 is electrically connected to the second end connector 232´ during the mechanical coupling of the panel 100 to the adjacent panel 100´. An electrical energy supply may be electrically connected to one end piece 200 and supply electric energy to a plurality of connected end pieces 200, each end piece 200 being mechanically coupled and electrically connected to a respective panel 100. Electrical energy may hence be provided from the electrical energy supply to the panels 100 via the end pieces 200. The provided electrical energy, e.g. a voltage generating heat in the panels 100, is encapsulated within the end pieces 200 and the panels 100. The end pieces 200 according to the invention hence minimizes the risk of getting an electric shock and increases the safety during installation of the panels 100. The invention is not limited to the above described embodiments. Instead, the invention relates to, and encompasses all different embodiments being included within the scope of the independent claims.

Claims

CLAIMS 1. An end piece (200) for providing electricity to a panel (100), the end piece (200) having a first longitudinal side (202) and an opposite second longitudinal side (204) extending between a first end (206) and an opposite second end (208), the end piece (200) comprising: - a coupling means (210) arranged at the first longitudinal side (202) of the end piece (200) for mechanically coupling the end piece (200) to an end side (104) of the panel (100), - a side connector (220) arranged at the first longitudinal side (202) of the end piece (200) for electrically connecting the end piece (200) to the panel (100), and - a first end connector (230) arranged at the first end (206) of the end piece (200) and a second end connector (232) arranged at the second end (208) of the end piece (200), the first end connector (230) and the second end connector (232) being electrically connected to each other and to the side connector (220); wherein - the first end connector (230) of the end piece (200) is arranged to be electrically connected to a second end connector (232´) of an adjacent end piece (200´) when a longitudinal side (106) of the panel (100), to which the end piece (200) has been mechanically coupled and electrically connected, is mechanically coupled to a longitudinal side (107) of an adjacent panel (100´), to which the adjacent end piece (200´) has been mechanically coupled and electrically connected.

2. The end piece (200) according to claim 1, wherein, when the first end connector (230) of the end piece (200) has been electrically connected to the second end connector (232´) of the adjacent end piece (200´), a heat providing layer (102) of the panel (100) is electrically connected to a heat providing layer (102´) of the adjacent panel (100).

3. The end piece (200) according to claim 1 or 2, wherein the first end connector (230) comprises a conductor part (231) arranged to be rotated into a complementary conductor part (233´) of the second end connector (232´) during the mechanical coupling of the panel (100) to the adjacent panel (100´).

4. The end piece (200) according to any one of the preceding claims, wherein the first end connector (230) comprises a protrusion (236, 238) and the second end connector (232) comprises a complementary recess (237, 239).

5. The end piece (200) according to claim 4, wherein the protrusion (236, 238) and the complementary recess (237, 239) extend in an extension of the first longitudinal side (202) of the end piece (200) or the second longitudinal side (202) of the end piece (200).

6. The end piece (200) according to claim 5, wherein the protrusion (238) extends further in the extension of the second longitudinal side (204) of the end piece (200) than a conductor part (231) of the first end connector (230).

7. The end piece (200) according to any one of the preceding claims, wherein one or more of the coupling means (210) and the side connector (220) comprises a self-locking member

8. The end piece (200) according to any one of the preceding claims, wherein the coupling means (210) comprises the side connector (220) or vice versa.

9. The end piece (200) according to any one of the preceding claims, wherein one or more of the coupling means (210) and the side connector (220) is arranged to be inserted into one or more longitudinal grooves (121) arranged in the panel (100).

10. The end piece (200) according to any one of the preceding claims, wherein the end piece (200) is non-conductive and encapsulates the electrical connections between the side connector (220), the first end connector (230) and the second end connector (232).

11. The end piece (200) according to any one of the preceding claims, wherein the end piece (200) comprises a displacement means (240) arranged to displace a conductor part (231) of the first end connector (230) outward from the first end connector (230) of the end piece (200), when the end piece (200) is folded down onto a surface.

12. The end piece (200) according to claim 11, wherein the displacement means (240) comprises an elongated element (244) attached to the conductor part (231) of the first end connector (230), the elongated element (244) comprising a joint (246) at least partly protruding from a bottom (201) of the end piece (200), in a relaxed state.

13. The end piece (200) according to claim 12, wherein the joint (246) is pushed into the end piece (200), when the end piece (200) is folded down onto the surface.