Lamp with an end wall solution independent of tolerance and thermal expansion

Abstract

The invention relates to a luminaire comprising: an extruded profile which is made of plastic, is at least partially translucent and forms a light exit region of the luminaire, an elongated support insert which is made of metal and carries lighting means, in particular LEDs, of the luminaire, wherein the extruded profile and the support insert can be plugged into one another along their longitudinal edges, wherein in the plugged-in state they can be displaced relative to one another in a longitudinal direction, and at least one end wall which can be plugged onto an end face of the extruded profile by means of a press fit in order to close the extruded profile and the support insert at the end face.

Description

[0001] The invention relates to a luminaire of elongated design, which has a separately attached end wall, as well as a rail system which accommodates several such luminaires.

[0002] Longitudinal luminaires are often made from extruded profiles, particularly for arranging these luminaires (also known as luminaire modules) lengthwise in a rail system. Sealing the end faces of the extruded profiles is a particular challenge, as material-related tolerances and thermal expansion can lead to leaks at the connection to the end wall. This is particularly problematic for luminaires that have to meet a high protection class, e.g. luminaires for industrial use. The extruded profiles are usually glued to the end faces to ensure the required protection class. However, these solutions are complex and expensive. Gluing makes final assembly time-consuming and costly. There is also a risk that the adhesive will peel off if components made of different materials experience uneven thermal expansion.

[0003] Other prior art solutions involve connecting end panels with a seal, either by means of screws or plastic snap hooks, to a support insert of the luminaire, onto which the extruded profile is attached. However, this poses the problem that the seal with the extruded profile is insufficient due to tolerance violations. Particularly with very long plastic profiles, there are often problems due to different thermal expansion coefficients between the support insert, which is usually made of metal, and the plastic profile.

[0004] Multi-part solutions that only seal the space around the lamp within the luminaire are also very costly and time-consuming in final assembly.

[0005] There is therefore a need for a tolerance and thermal expansion independent end face solution for luminaires, which includes extruded profiles and support inserts made of different materials, in particular a material mix of plastic and metal.

[0006] The object is achieved by a luminaire according to claim 1 and by a rail system with such luminaires according to claim 12.

[0007] A special feature of the luminaire according to the invention is the type of end wall used to close the luminaire at the front. In contrast to prior art solutions, the end wall is not permanently attached to the metal support insert for the light source, but is press-fitted onto the extruded plastic profile. The front side only rests laterally against the support insert, possibly with an additional seal. As a result, the load-bearing function that the metal support insert usually performs in a luminaire is no longer present in the solution according to the invention for the end wall. The end wall is only indirectly connected to the support insert via the extruded profile. This makes it easier to compensate for the tolerances caused by different thermal expansions of the components.This is particularly important for elongated luminaires because, due to the long extension of the extruded profile and the support insert, the different thermal expansions can lead to large gaps between the components.

[0008] According to a preferred embodiment, a seal is arranged between the end wall and a portion of the extruded profile and the support insert. The seal is preferably formed from a foam material. The foam material is particularly soft and thus makes it possible to ensure a seal from the side wall to both the extruded profile and the support insert, even if the extruded profile and the support insert penetrate the seal to different depths, e.g., due to different thermal expansions due to the different materials.

[0009] According to a preferred embodiment, the seal seals only a portion of an end edge of the extruded profile, while in the remaining portion of the end edge of the extruded profile, a web of the end wall penetrates into the extruded profile or engages around it. In addition to the press fit, the web serves to align the end wall with respect to the extruded profile. Furthermore, the web can also serve to seal the luminaire in the area in which no seal is arranged. This embodiment has the advantage that the seal is only required for a portion of the end edge of the extruded profile, namely preferably in the portion in which a seal with respect to the support insert is also required.The remaining area of ​​the front edge of the extruded profile does not require a separate seal because sufficient tightness can be achieved solely through the contact between the end wall and the extruded profile, both of which are made of plastic. In this embodiment, the seal between the extruded profile and the end wall in the area outside the support insert is achieved solely through the web. This embodiment therefore saves material, and the web, in addition to the press fit, supports precise alignment of the end wall with respect to the extruded profile.

[0010] According to a preferred embodiment, the web extends along a circumference of the end wall on the side facing the extruded profile, with the exception of the partial area in which the seal is arranged between the front edge of the extruded profile and the end wall. In the area of ​​the seal, the circumferential web is not necessary because in this area the seal seals the end wall not only against the support insert, but also against the extruded profile.

[0011] According to a preferred embodiment, the seal rests flat against a partial area of ​​an inner side of the end wall and is clamped between an end edge of the support insert and the end wall. The seal can be formed from a flat, particularly planar, material section. This embodiment is therefore particularly easy to manufacture.

[0012] According to a preferred embodiment, the end wall in the region of the seal has recesses on the side facing the seal, into which the seal is pressed upon contact with the carrier insert. The recesses also serve to accommodate construction tolerances and thermal expansion changes. The seal, which is preferably formed from a foam material, can be compressed to a large extent. However, to provide sufficient buffer zone, the recess serves to accommodate part of the material thickness of the seal in the compressed state.

[0013] According to a preferred embodiment, the seal is held in position on the side wall by form-fitting elements. The form-fitting elements can, for example, be in the form of pins that protrude from the end wall towards the extruded profile, and corresponding recesses can be provided on the seal that are plugged onto the pins. In principle, however, other forms of form-fitting connections are also possible. For example, webs can be provided that engage in recesses in the seals, or the seal can have projections that engage in recesses in the end wall. The form-fitting offers the advantage that the seal can already be positioned on the end wall before the end wall is press-fitted onto the extruded profile. This facilitates the assembly of the luminaire.

[0014] According to a preferred embodiment, the end wall has one or more sliding bearings on a side facing the support profile, which bearings rest against one side of the support insert and are held in a sliding manner thereon. The sliding bearings also serve to align the end wall with respect to the support insert and the extruded profile. The sliding bearings can, for example, be designed as straight hooks that are guided along an upper side of the support profile. It is important, however, that the hooks are not completely fixed to the support profile, but can slide along it, with the sliding movement occurring along the longitudinal extent of the support profile or the extruded profile. This makes it possible to compensate for the tolerance between the two components if the thermal expansion of the support profile differs from that of the extruded profile.The end wall remains firmly connected to the extruded profile, while it can move in the longitudinal direction of the luminaire relative to the support insert. However, since the plain bearings prevent the end wall from moving lateral (i.e., perpendicular to the longitudinal extension of the luminaire), the plain bearings support the precise alignment of the end wall relative to the luminaire.

[0015] According to a preferred embodiment, the one or more sliding bearings are held in place by a spring engaged with the support insert. This facilitates assembly of the luminaire, and the spring can also serve as a fastening element for the luminaire.

[0016] According to a preferred embodiment, the press fit between the extruded profile and the side wall is formed by at least two domes on the end wall, wherein the domes penetrate into the extruded profile and are fixed in the extruded profile by pressing. Two domes are advantageous because they establish the lateral alignment of the end wall with respect to the extruded profile without allowing the end wall to rotate with respect to the extruded profile. Furthermore, the domes have the advantage that they can be easily inserted into recesses in the end wall which are already formed by a cross-sectional contour of the extruded profile. The domes are preferably provided adjacent to the seal because a particularly high pressing force is required for sealing in this area.

[0017] According to a preferred embodiment, the end wall has an external seal on an outer side, which is intended and configured to form a sealing contact with an adjacent luminaire. The external seal is formed independently of the seal in the preceding embodiments and is provided on the outer side of the end wall. These seals serve to seal adjacent luminaires, in particular in a track system in which several such luminaires are adjacent one behind the other. If the luminaires are adjacent to one another with their end faces, the area between the end walls can be sealed by one external seal or by two external seals on adjacent luminaires, so that no foreign bodies can enter the track system through a gap between two luminaires.

[0018] According to a further aspect of the invention, a rail system is provided which accommodates a plurality of the luminaires according to one of the preceding embodiments, adjacent to one another in a longitudinal direction at their ends, wherein a support rail of the rail system extends lengthwise over the plurality of luminaires and covers the luminaires at least in the region of the support inserts of the luminaire. Rail systems are preferred for such luminaires because they allow many luminaires to be aligned one behind the other to form a light strip. Since the installation position is fixedly predetermined by the rail system, the luminaires are already laterally aligned with one another after they have been plugged into the rail system. The rail system preferably has through-wiring into which the luminaires engage in order to make electrical contact therewith.

[0019] According to a preferred embodiment, two of the plurality of luminaires are adjacent to each other with their external seals. As previously stated, the external seals serve to prevent foreign objects from penetrating the track system between the luminaires.

[0020] According to a preferred embodiment, the track system is sealed to protection class IP54 or higher. The special design of the luminaire with the end cap attached to the extruded profile allows for a high protection class to be achieved without any special structural effort and with comparatively few individual components. Protection class IP54 or higher is preferred for industrial applications, e.g., in production halls where high levels of dust are present.

[0021] Further advantages and features of the present invention will become apparent from the following description of preferred embodiments, which is given in conjunction with the accompanying figures. The figures show the following: Figure 1 shows a perspective view of the front of a luminaire according to an embodiment of the invention. Figure 2 shows an exploded view of the luminaire according to Figure 1 Figure 3 shows a perspective view of the end wall as a single part. Figure 4 shows a perspective view of the extruded profile as a single part.

[0022] The luminaire shown in the figures is elongated and comprises a support insert 1, which is made of a metal sheet and has one or more rows of LEDs along its length (not shown in the figures). An extruded profile 2 is placed lengthwise on the support insert 1 from below. The extruded profile 2 is made of a plastic, preferably in an extrusion process, and has a continuous cross-sectional shape along its longitudinal extent, as shown, for example, in Figure 4 viewed from one end face. The extruded profile 2 has a transparent area on at least one side 22, which in the assembled luminaire is opposite the support insert, which serves as the light exit surface of the luminaire. The longitudinal side parts of the extruded profile 2 can also be formed from a transparent material and serve at least partially as the light exit surface of the luminaire.

[0023] On the side of the extruded profile 2 facing the support insert 1, the extruded profile 2 has locking projections 23 along its length, which can be connected to resilient side wall sections 11 on the longitudinal edges of the support insert 1. For example, the extruded profile 2 can be inserted into the support insert 1 from below, with the resilient side wall sections 11 being deflected until the locking projections 23 engage behind them. Alternatively, the extruded profile 2 can also be inserted lengthwise into the support insert 1.

[0024] According to the invention, the luminaire is closed on at least one end face with a separate end wall 3. The end wall 3 comprises an outer contour that approximately corresponds to the end profile of the support insert 1 and the extruded profile 2 when connected. The end wall 3 serves to seal the luminaire as tightly as possible at the end face. A particular difficulty is that the support insert 1, which is made of sheet metal, and the extruded profile 2, which is made of plastic, can expand differently. The end wall 3 is designed so that it can still seal the extruded profile or the support insert even with different longitudinal expansions.For this purpose, several domes 31, in the present example two, are provided on the end wall 3 on the side facing the extruded profile 2, which domes can be inserted into recesses 21 of the extruded profile, thereby forming a press fit between the dome 31 and the recess 21. This press fit serves to connect the end wall 3 to the extruded profile 2. The press fit is further supported by the fact that the end wall 3 also has a circumferential web 32 directly adjacent to the dome 31 on the side facing the extruded profile 2, which web also engages in the extruded profile 2 in the assembled state and rests against the inside of the extruded profile 2 along its entire circumference in the area outside the support insert 1. Preferably, the web 32 rests against the inside of the extruded profile in such a way that a sealed connection is already formed.

[0025] A special feature when mounting the side wall 3 on the luminaire is that the press fit of the side wall 3 is only achieved with the extruded profile 2 by the domes 31 being pushed into the recesses 21. In contrast, there is no press fit between the support insert 1 and the end wall 3. This makes it possible for the support insert 1 to expand differently than the extruded profile 2 without the end wall being displaced. The alignment of the end wall relative to the support insert 1 is additionally supported by two slide bearings 33, which are provided on the side of the end wall 3 facing the end of the support insert 1. The slide bearings 33 are designed as elongated elements and rest on the support insert 1, but are not firmly connected to the support insert 1 in the longitudinal direction. This allows the slide bearings 33 to slide along the support insert 1 when the support insert moves with respect to the extruded profile 2 orthe associated end wall 3 moves, for example, due to thermal expansion. The plain bearings 33 are additionally held on an upper side of the carrier insert 1 by a spring 4, as shown in the . Figures 1 and 2 The spring 4 is an element that can be inserted into the support insert 1 and is resiliently held thereon. A space is formed in the gap between a central region of the spring 4 and an upper side of the support insert 1, in which the sliding bearings are held without rigidly securing them relative to the support insert. The sliding bearings thus serve to stabilize the alignment of the end wall 3 relative to the support insert 1 in the lateral direction.

[0026] In order to improve the seal between the end wall 3 and a portion of the extruded profile 2 and the support insert 1, a seal 5 is provided according to the invention, which is first connected to the end wall 3 before the end wall 3 is attached to the extruded profile 2. The seal 5 is made of a soft foam material and, in the illustrated embodiment, has two openings through which the seal 5 is attached to two pins 34 of the end wall. The pins 34 therefore form the positive locking element for holding the seal 5 to the end wall even before the end wall 3 is attached to the extruded profile 2.

[0027] The seal 5 lies flat against an inner side of the end wall 3, but only in an area in which the support insert 1 also lies against the side wall 3 later during assembly of the end wall 3 to the extruded profile 2. The seal 5 therefore only serves to seal a partial area of ​​the end wall 3. In order to improve the seal between the end wall 3 and the support insert 1, even in the event of different thermal expansion, recesses 35 are provided on the end wall 3. In the assembled state, the seal 5 is squeezed into the recesses 35, as shown in the perspective view according to Figure 1 can be seen in the area of ​​the seal 5. Since the seal is made of a relatively soft foam material, different gap dimensions to the support insert 1 caused by thermal expansion can be compensated, while the connection from the end wall 3 to the extruded profile 2 is rigid.

[0028] As an alternative to the seal 5, the end wall 3 could also be provided to laterally surround the support insert 1 and be displaceable longitudinally against it, in order to provide protection, for example, against the ingress of splash water. However, to achieve a high protection class, e.g., IP 54 or higher, the separate seal 5 is preferred.

[0029] In the illustrated embodiment, the luminaire is shown only at one end. However, according to a preferred embodiment, the same end wall 3 is also provided on the opposite end of the luminaire. Alternatively, only one end wall 3 can be provided on the luminaire, while the opposite end is closed by a different structure, e.g., with a cable inlet.

[0030] The luminaire in the illustrated embodiment can in principle be used as a single luminaire, for example as a ceiling surface-mounted or suspended luminaire. However, the integration of the luminaire, which in this case is also referred to as a lighting module, into a track system is preferred. For this purpose, the luminaire is inserted into a support rail (not shown in the figures) with the support insert 1 facing forward from below. The support rail can seal the entire area of ​​the luminaire in which the support insert 1 is located, so that no separate seals against splash water are required in this area. However, the connection between the support insert 1 and the extruded profile 2 is preferably additionally improved by a longitudinal seal, for example a felt element. This protects the luminaire against the ingress of dust, while the ingress of splash water is already prevented by the support rail above it and the end wall 3.

[0031] Furthermore, an external seal 6 is provided on an outward-facing section of the end wall 3, which serves to form a seal with an adjacent luminaire at the end. In particular, to form a light strip, it is often desired to have luminaires of the aforementioned type adjacent to one another at the end, close to one another. In order to prevent dust or moisture from entering a rail system that supports the luminaires, the external seal 6 can be attached to at least one of the luminaires, which forms a seal with the end wall of the adjacent luminaire. The adjacent luminaire can also have an external seal 6, so that the two seals 6 abut one another, or only one luminaire can have an external seal 6 that abuts an end wall section of the adjacent luminaire.

[0032] The embodiment shown in the figures represents only one example of an embodiment of the invention, which is defined in the claims. In particular, the cross-sectional shape of the extruded profile 2 and the support insert 1 can be varied. However, it is preferred that the extruded profile and the support insert have a continuous cross-sectional shape in their longitudinal extent. The shape of the end wall 3 can also vary, although this is generally designed such that it completely covers the frontal periphery of the luminaire. The number of domes 31 or, in general, the elements that form the press fit to the extruded profile can vary depending on the required holding force to hold the side wall. Furthermore, an additional seal can also be provided between the web 32 and the extruded profile 2.Preferably, however, the seal 5 for sealing the end wall 3 against the support profile 1 is limited to only a partial area, and any additional seals are provided separately. This has the advantage that the material and thickness of the seal 5 can be matched to the expected gap tolerances that arise during typical thermal expansion between the length of the support insert 1 and the length of the extruded profile 2. List of reference symbols

[0033] 1Support insert 11Resilient side wall section 2Extruded profile 21Recess 22Light exit area 23Locking projection 3End wall 31Dome 32Circumferential web 33Sliding bearing 34Form-locking element, in particular pin 35Recess 4Spring 5Seal 6External seal

Claims

1. A luminaire comprising: an extruded profile (2) which is made of plastic, is at least partially translucent and forms a light exit region (22) of the luminaire, an elongated support insert (1) which is made of metal and carries lighting means, in particular LEDs, of the luminaire, wherein the extruded profile (2) and the support insert (1) can be plugged into one another along their longitudinal edges, wherein in the plugged-in state they can be displaced relative to one another in a longitudinal direction, and at least one end wall (3) which can be plugged onto an end face of the extruded profile (2) by means of a press fit in order to close the extruded profile (2) and the support insert (1) at the end.

2. Luminaire according to claim 1, wherein a seal (5) is arranged between the end wall (3) and a region of the extruded profile (2) and the support insert (1).

3. Luminaire according to claim 2, wherein the seal (5) seals only a partial area of ​​an end edge of the extruded profile (2), while in the remaining area of ​​the end edge of the extruded profile (2) a web (31) of the end wall (3) penetrates into the extruded profile (2) or surrounds it.

4. Luminaire according to claim 3, wherein the web (31) extends along a circumference of the end wall (3) on the side facing the extruded profile (2) with the exception of the partial area in which the seal (5) is arranged between the front edge of the extruded profile (2) and the end wall (3).

5. Luminaire according to one of claims 2 to 4, wherein the seal (5) is held in position by form-locking elements (34) of the side wall (3).

6. Luminaire according to one of claims 2 to 5, wherein the seal lies flat against a partial area of ​​an inner side of the end wall (3) and is clamped between an end edge of the support insert (1) and the end wall (3).

7. Luminaire according to one of claims 2 to 6, wherein the end wall (3) in the region of the seal (5) on the side facing the seal (5) has recesses (35) into which the seal (5) is pressed upon contact with the carrier insert (1).

8. Luminaire according to one of the preceding claims, wherein the end wall has one or more sliding bearings on a side facing the support profile, which bearings rest against one side of the support insert and are held slidingly thereon.

9. Luminaire according to the preceding claim, wherein the one or more sliding bearings (33) are held slidingly by a spring (4) engaged on the support insert (1).

10. Luminaire according to one of the preceding claims, wherein the press fit between the extruded profile (2) and the side wall (3) is formed by at least two domes (31) on the end wall, wherein the domes (31) penetrate into the extruded profile (2) and are fixed in the extruded profile (2) by pressing.

11. Luminaire according to one of the preceding claims, wherein the end wall (3) has on an outer side an external seal (6) which is intended and arranged to form a sealing contact with an adjacent luminaire.

12. Rail system which accommodates a plurality of the luminaires according to one of the preceding claims in a longitudinal direction adjacent to one another at the end, wherein a support rail of the rail system extends lengthwise over the plurality of luminaires and covers the luminaires at least in the region of the support inserts (1) of the luminaire.

13. A track system according to claim 12 with reference back to claim 11, wherein two of the plurality of luminaires are adjacent to one another with their external seals (6).

14. Rail system according to claim 12 or 13, which has a tightness according to protection class IP54 or higher.

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