The invention relates to a housing for receiving a lamp base, more particularly a base with Edison screw thread.

PRI OR ART

A housing for receiving a base of an iconic lamp with an Edison screw thread is known from the prior art. Such housings are still widely used. The lamp herein has a known shape, comprising a bulb, a neck, and a base. The shell of the base is provided with an Edison screw thread, whereby the base can be screwed into a holder. The holder internally comprises a complementary screw thread. A holder is therein internally provided with two contact points which provide the electrical energy transfer, as a result of which the lamp can light up. However, today an enormous number of variants of the lamp can be found. All these variants always have one part in com mon, namely the base. The base is standardized and exists in a lim ited number of variants.

The disadvantage of such lamps is that, in addition to their base, all variants also have a neck between the base and the bulb of the lamp. The neck as well as the bulb are not standardized and can be of many shapes and sizes. As a result, the bulb of the lamp is often far from the housing and the neck and therefore the bulb is usually not or only poorly supported by the housing.

An additional drawback of such known lamps and housings is that when the lamp is screwed into the holder, it is placed visually obliquely in the holder through a contact point between the holder and the base of the lamp. This is often not desirable.

Another problem with such known lamps and associated holders is that it very often occurs that dust and/or moisture can penetrate between the base and the housing. This leads to dangerous situations such as sparks or short circuits, which can develop into a fire or in the best case a power failure.

KR 101 133 579 describes a waterproof pear-shaped LED lamp with a waterproof protection around the holder for the LED lamp. GB 288 998 discloses a holder for receiving a bulb of a lamp. A screen is screwed onto the holder.

GB 488 119 describes a holder for an Edison lamp. A shielding ring is screwed onto the holder to shield parts of the holder or the Edison lamp.

GB 1 156 350 concerns a housing for a lamp. The housing comprises a ring which is prestressed against the bulb of the lamp in order to prevent damage to the lamp and in particular the filament in the event of a mechanical impact.

DE 247 732 is related to a holder for an Edison lamp with a screen screwed onto the holder.

In DE 314 087, a holder for a light bulb is disclosed. The holder has a protective ring that is pressed against the bulb of the light bulb by means of a spring.

US 4 704 668 describes a sleeve-shaped stabilizer for a lamp.

The present invention aims at solving at least one of the said and other disadvantages.

SUMMARY OF TH E I NVENTI ON

In a first aspect, the invention relates to a housing for receiving a lamp base according to claim 1 .

The advantage of such a housing is that when a lamp is screwed into a holder, a collar can be moved in the direction of the axis of the cylindrical shell of the holder, until it connects over the neck to the bulb of the lamp. The neck is therefore completely hidden by the collar and the collar ensures that the bulb is better supported.

Preferred embodiments of the housing are described in claims 2-10.

A specific preferred embodiment relates to the housing according to claim 2. Because the external screw thread of the cylindrical shell and the complementary screw thread of the collar have a different m inor diameter, there is play between the holder and the collar.

The advantage of the play is that the collar is placed diagonally over the holder when it connects with one end over the neck to the bulb of the lamp. As a result, the collar is aligned straight against the bulb of the lamp.

A specific preferred embodiment relates to the housing according to claim 6. This embodiment has the advantage that no dust and/or moisture can get between the holder and the base of the lamp. This provides better protection against a possible fire or power failure.

A specific preferred embodiment relates to the housing according to claim 7. This embodiment has the advantage that the lamp is not only straight with respect to the collar, but now also with respect to the housing.

I n a second aspect, the invention relates to the use of a housing according to the first aspect as a standard lamp, table lamp, pendant lamp, or recessed lamp. An advantage of using a housing according to the first aspect in, for example, a standard lamp, table lamp, pendant lamp or recessed lamp is that only the bulb of the lamp is visible. It is advantageous here that the lamp is better supported in the housing, so that a lamp will break off less quickly at the neck in the event of impact. These standard lamps, table lamps, pendant lamps, or recessed lamps, in combination with a simple sealing ring, can now also be used advantageously in damp or dusty areas without having to provide expensive fixtures where it is difficult to replace the lamp should it break down. An additional advantage is that because the lamp is straight with respect to the collar and the lamp is fixed in the housing with the collar, the lamp is now also straight with respect to the housing. Figure 1 shows a cross-section of a lamp in a housing according to an embodiment of the present invention.

Figure 2 shows a cross-section of a lamp in a housing according to an alternative embodiment of the present invention.

Figure 3 shows a cross-section of a lamp in a ceiling according to yet another alternative embodiment of the present invention.

DETAI LED DESCRI PTI ON

Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meaning as commonly understood by a person skilled in the art to which the invention pertains. For a better understanding of the description of the invention, the following terms are explained explicitly.

I n this document, “a” and “the” refer to both the singular and the plural, unless the context presupposes otherwise. For example, “a segment” means one or more segments.

When the term “around” or “about” is used in this document with a measurable quantity, a parameter, a duration or moment, and the like, then variations are meant of approx. 20% or less, preferably approx. 10% or less, more preferably approx. 5% or less, even more preferably approx. 1 % or less, and even more preferably approx. 0.1 % or less than and of the quoted value, insofar as such variations are applicable in the described invention. However, it m ust be understood that the value of a quantity used where the term “about” or “around” is used, is itself specifically disclosed.

The terms “comprise”, “comprising”, “consist of”, “consisting of”, “provided with”, “include”, “including”, “contain”, “containing”, are synonyms and are inclusive or open terms that indicate the presence of what follows, and which do not exclude or prevent the presence of other components, characteristics, elements, members, steps, as known from or disclosed in the prior art. Quoting numerical intervals by endpoints comprises all integers, fractions and/or real numbers between the endpoints, these endpoints included.

The term “holder” in this text is considered a holder for connecting a lamp, wherein the holder comprises a cylindrical shell, a closed lower surface, and an open upper surface. The holder com prises on the cylindrical shell an internal screw thread for screwing a lamp into the holder, the holder comprising a first contact point on the lower surface and a second contact point on the shell for electrically connecting the lam p. The holder has a longitudinal direction equal to the direction of the axis of the cylindrical body.

The term “base” in this text is intended to m ean an end and part of a lamp that is screwed into a holder. The base comprises two contact points, the base com prising a first contact point on a tip facing the holder and a second contact point on a shell of the base. Preferably, the shell of the base is the second contact point.

The term “abutting with” in this text is intended to m ean a joining of a first elem ent to a second elem ent, the joining having a shape which follows a shape of the second elem ent and the joining making contact with said shape of the second elem ent or following said shape of the second elem ent with a spacing of at most 5m m , preferably at most 4m m , more preferably at most 3m m and even more preferably at most 2m m .

The term “abutting against” herein refers to a joining of a first elem ent to a second elem ent, the joining extending up to a point of the second elem ent, the joining making contact with said point of the second element or wherein between the joining and said point of the second elem ent there is a gap of at most 3m m , preferably at most 2m m , more preferably at most 1 m m and even more preferably at most 0.5m m .

“ Placing around” in this document refers to a first elem ent which hides a second elem ent from view but does not necessarily m ake contact to do so. I t will be apparent to one skilled in the art that a first elem ent m ay be positioned around a second elem ent sim ultaneously as it may abut with the second elem ent.

The invention relates in a first aspect to a housing for receiving a lamp base.

According to a preferred em bodim ent, the housing comprises a holder and a collar. The collar is placed around at least part of the cylindrical shell of the holder, and the collar is movable in the direction of the axis of the cylindrical shell. The collar comprises a cylindrical shell with an open end. The diameter of the open end is preferably greater than the diameter of the neck of the lamp.

A lamp, which is screwed into the holder, comprises a base with Edison screw thread. The lamp further comprises a neck and bulb, the neck being located between the base and the bulb. The neck of the lamp is a part that often houses a control for a light source in the bulb. Depending on the light source used, the control can change in dimensions. This also affects the dimensions of the neck of the lamp. This can therefore occur with different widths and lengths. This is also the case for the shape of the bulb. Unlike the bulb, the neck is not an aesthetic element of the lamp and is best concealed. Neither the neck nor the bulb are standardized.

A holder according to the present embodiment is advantageous because the collar can be moved over the holder in the direction of the lamp, so that it abuts with one end against the bulb of the lamp or abuts with the bulb of the lamp with a minimal gap. As a result, the lamp is better supported, the lamp is less prone to breaking off and the neck of the lamp is invisible, so that only the aesthetic element of the lamp, the bulb, is visible. It is also advantageous that the collar, due to its cylindrical shell, can abut against the bulb of the lamp or abut with the bulb of the lamp over different types of necks, as long as the neck of the lamp is smaller than the diameter of the collar.

According to a preferred embodiment, the holder comprises an external screw thread on the cylindrical shell. The collar comprises a complementary screw thread on a side facing the holder, wherein the external and the complementary screw thread have the same pitch, but a different m inor diameter. Due to the deviating minor diameters, there is play between the external screw thread of the holder and the complementary screw thread of the collar.

A characteristic of the Edison screw thread on the base of the lamp is that there is play between the diameter of the base of the lamp and the diameter of the opening in the holder. Due to the second contact point in the holder, it is possible that the lamp will be visually slanted in the holder when screwing in the lamp.

An advantage of the play between the holder and the collar is that the collar can be positioned obliquely relative to the holder and as a result, after the collar has been moved until it abuts against or with a minimal gap at the bulb of the lamp, the collar is aligned perpendicular to the bulb of the lamp. The collar is therefore positioned obliquely on the holder at an angle equal to the angle between the lamp and the holder.

According to a further embodiment, the minor diameter of the external thread on the cylindrical shell of the holder is at least 98.1% and at most 99.0% of the minor diameter of the complementary thread of the collar.

Preferably, the minor diameter of the external screw thread on the cylindrical shell of the holder is at least 98.2% of the minor diameter of the complementary screw thread of the collar, more preferably at least 98.3%, even more preferably at least 98.4% and even more preferably at least 98.5%.

Preferably, the minor diameter of the external screw thread on the cylindrical shell of the holder is at most 98.9% of the minor diameter of the complementary screw thread of the collar, more preferably at most 98.8%, even more preferably at most 98.7% and even more preferably at most 98.6%.

A minor diameter of the external screw thread on the cylindrical shell of the holder within this range has sufficient play to position the collar obliquely relative to the holder so that after displacement the collar abuts against the bulb of the lamp or abuts with the bulb of the lamp with a minimal gap and the play is not too great, so that the collar cannot be moved to near or against the bulb with sufficient precision, so that in a number of cases a large gap would arise.

According to a further embodiment, the external screw thread on the cylindrical shell has a minor diameter of at least 37.5 mm and at most 38.2 mm.

The external screw thread on the cylindrical shell preferably has a diameter of at most 38.1 mm, more preferably at most 38.0 mm and even more preferably at most 37.9 mm.

The external screw thread on the cylindrical shell preferably has a diameter of at least 37.6 mm, more preferably at least 37.7 mm and even more preferably at least 37.8 mm. A minor diameter of the external thread on the cylindrical shell of the holder within this range is suitable for a holder for a lamp with an E27 base.

According to a preferred embodiment, the housing comprises a retention ring, the retention ring being placed around the cylindrical shell of the holder. The retention ring comprises a complementary screw thread on a side facing the holder. The complementary screw thread is complementary to external screw thread on the cylindrical shell of the holder as in a previously described embodiment. This complementary screw thread has a minor diameter which is at least 1 .3% and at most 2.1 % larger than the minor diameter of the external screw thread on the cylindrical shell of the holder.

The minor diameter of the complementary screw thread is preferably at least 1 .4% larger than the m inor diameter of the external screw thread on the cylindrical shell of the holder, more preferably at least 1 .5% and even more preferably at least 1 .6% .

The m inor diameter of the complementary screw thread is preferably at most 2.0% larger than the m inor diameter of the external screw thread on the cylindrical shell of the holder, more preferably at most 1 .9% and even more preferably at most 1 .8% .

The retention ring is advantageous because the collar, which abuts against the bulb of the lamp or abuts with the bulb of the lamp with a minimal gap, can be secured so that the collar can no longer move by itself. The play between the retention ring and the holder is also advantageous for absorbing the play between the collar and holder. As a result, the retention ring makes contact with the collar around the entire circumference.

According to a preferred embodiment, the collar comprises a cup-shaped edge at one end, the cup-shaped edge abutting with the neck of the lamp or abutting against the bulb of the lamp. Preferably, the cup-shaped edge abuts with the neck of the lamp and abuts against the bulb of the lamp.

Ordinary lamps have a neck between the base and the bulb of the lamp. Like the collar, many of the lamps on the market have a cup-shaped neck. An advantage of such a cup-shaped edge is that it has a shape which is broadly similar to that of the neck of the lamp. As a result, the lamp is also supported at the neck by the collar, so that a lamp is even less sensitive to breaking.

According to a further embodiment, the cup-shaped edge of the collar abuts with the neck of the lamp with a gap between the cup-shaped edge and the neck or the bulb of the lamp, which is at most 2 mm .

The gap between the cup-shaped edge and the neck or bulb is preferably at most 1 .8mm , more preferably at most 1 .6m m , even more preferably at most 1 .4mm and even more preferably 1 .2m m .

According to one embodiment, the cup-shaped edge of the collar abuts with the neck of the lamp with a gap between the cup-shaped edge and the neck or the bulb of the lamp, which is at least one 0.1 mm .

The gap between the cup-shaped edge and the neck or bulb is preferably at least 0.3mm , more preferably at least 0.4m m , even more preferably at least 0.6m m and even more preferably 0.9m m .

According to one embodiment, the collar has a maximum diameter of 57mm . Because the collar is dimensioned with a maximum diameter of 57mm it is thus possible to fit over the necks of the most com mon lamps available on the market. The bases of lamps available with an Edison thread on the shell of the base have a typical diameter between 14- 40m m . There are different variants of bases on the market, in particular: E5 with a base diameter of 5m m , E10 with a base diameter of 10mm , E12 with a base diameter of 12m m , E14 with a base diameter of 14-17m m , E17 with a base diameter of 14-17mm , E26 with a base diameter of 25-26mm , E27 with a base diameter of 25-26m m , E27 with a base diameter of 26-27mm and E40 with a base diameter of 40mm .

An advantage of a collar with a maximum diameter of 57 is that it fits over most lamp necks. It is possible to provide a single collar per type of Edison screw thread, which fits over a large part of the different possible necks. This makes it easier for the production process and lim its the use of materials. According to a preferred embodiment, a sealing ring is placed between the collar and the neck of the lamp. This sealing ring is preferably an elastic material, more preferably rubber. As a result, the sealing ring fits completely between the edge of the collar and the neck of the lamp. The sealing ring forms a watertight and dust- tight seal between the collar of the lamp and the glass of the lamp.

An advantage of this sealing ring is that it prevents dust and moisture from penetrating between the base of the lamp and the holder. This is particularly advantageous for safety as it prevents sparking and thus fire. Another advantage is that the housing can be used in a damp room such as the bathroom . Due to the waterproof properties, it is therefore not possible for moisture to get between the base of the lamp and the holder. As a result, this is a protection against short circuit, electrocution, and possible power loss.

A sealing ring of elastic material is particularly advantageous in combination with a previously described embodiment in which the collar comprises a cup-shaped edge, in that the sealing ring takes over the cup shape and forms a guaranteed seal.

According to a preferred embodiment, the collar comprises on a side facing away from the holder an attachment means for fastening the collar in the housing. Such attachment means could be a leaf spring, a compression spring, a bolt connection, a magnet, and an annular coil spring. The holder is held in the housing by means of the collar. Because the holder is held in the housing by means of the collar, the holder can be positioned obliquely relative to the bulb of the lamp, while the collar, the housing and the bulb are aligned straight with respect to each other. This prevents the bulb of the lamp and the housing from being visually oblique to each other.

According to a further embodiment, the attachment means is an annular coil spring, wherein the annular coil spring is positioned in a sem icircular recess around the circumference of the collar. The annular loops of the coil spring are positioned at an angle of 40° to 70° relative to the axis of the annular shape. This causes the loops of the annular coil spring under pressure to move closer to the axis of the annular shape, allowing the annular coil spring to assume a flat annular shape. The semicircular recess in the collar has a radius at least equal to the radius of the loops of the spiral shape in the annular coil spring. The annular coil spring is releasably located in the semicircular recess of the collar. The diameter of the annular shape of the annular coil spring is preferably smaller than the diameter of the collar at the level of the semicircular recess in the collar. This has the advantage that the annular coil spring is under tension in the recess of the collar so that it remains in place and cannot slip off. The housing comprises a semicircular recess on a side facing the collar. The semicircular recess in the housing has a radius at least equal to the radius of the loops of the spiral shape in the annular coil spring. The semicircular recess in the housing is annular. The diameter of the semicircular recess in the housing is at least 0.1 mm larger than the diameter of the collar and at most 1 mm larger than the diameter of the collar. By pressing the collar into the housing, the annular coil spring deforms until the annular coil spring is received in the semicircular recess in the collar and in the semicircular recess in the housing, after which the collar is releasably secured to the housing. This is advantageous for a releasable attachment of the collar to the housing without the use of tools.

According to one embodiment, the housing is a cylindrical body, wherein the collar and the holder are placed in the circular body. This is advantageous because as a result a minimal housing is obtained, which abuts as closely as possible with the base and the neck of the lamp, while the holder, collar and retention ring are hidden.

This embodiment is particularly advantageous with a previously described embodiment wherein the attachment means for securing the collar in the housing is an annular coil spring. Like the collar, the circular body has a semicircular recess of the same radius as that of the collar. The diameter of the circular housing at the position of the recess is preferably approximately equal to the diameter of the collar at the height of the recess. This recess is suitable for receiving an annular coil spring. Since the diameter of the housing and the collar at the level of the semicircular recess are approximately the same, the annular coil spring will come under pressure when the collar is received in the housing. As a result, the annular coil spring will deform as previously described, allowing the semicircular recess of the collar and housing to be aligned. When the semicircular recesses are aligned, the annular coil spring will return to its original shape and secure the collar in the housing.

According to a further embodiment, the cylindrical body is attached to a board at one end. The cylindrical body comprises a circular opening for receiving the base of the lamp. The axis of the cylindrical body is transverse to the circular opening and passes through the center of the circular opening. The board is rectangular, circular, or other suitable shape. The board has mounting holes for screwing the board to a surface. This is advantageous for fixing the housing in, for example, a cavity in a wall or in a ceiling.

The board is a metal plate for visible finishing of the board on the ceiling or wall. Alternatively, the board is a plastic sheet for an invisible finish in a wall or ceiling, where the plastic sheet is plastered. The plastic sheet preferably comprises ridges for better plaster adhesion.

An advantage of such a housing is that the underside of the bulb of the lamp is brought completely up to the circular opening of the cylindrical body. This connects the bulb to the board and the neck of the lamp is concealed in the housing. The lamp sits directly opposite the board because the lamp connects perpendicularly to the collar. This is particularly advantageous in combination with a plastic sheet, making the bulb of the lamp the only visible element from the wall or ceiling.

According to one embodiment, the housing is a board. The board is for instance part of a piece of furniture, such as for instance a wall cabinet. The board is, for example, a board of a ceiling, such as a plasterboard, a ceiling tile, or a concrete slab. The board comprises a circular opening. The circular opening has a diameter greater than a diameter of the holder. The collar comprises a cylindrical or conical volume with an open end for receiving the base of the lamp. Said volume comprises at its open end an annular projection circumferentially surrounding said volume. The annular projection extends transversely to said volume. The annular projection has an outer diameter that is at least greater than the diameter of the circular opening. The holder is placed through the circular opening. The annular projection is positioned against a first side of the board. The collar comprises an attachment means for securing the collar in the housing. The attachment means is a spring element. The spring element presses against a second side of the board. The second side of the board lies opposite the first side of the board. The annular projection and the spring element are advantageous for retaining the holder and the collar in the circular opening. As in a previously described embodiment, the holder is retained in the housing by means of the collar. This embodiment is advantageous because the base and the neck of the lamp, as well as the holder and the collar are completely hidden.

I n a second aspect, the invention relates to a use of a housing according to the first aspect as a standard lamp, table lamp, pendant lamp, or recessed lamp. An advantage of using a housing according to the first aspect in, for example, a standard lamp, table lamp, pendant lamp or recessed lamp is that only the bulb of the lamp is visible. It is advantageous here that the lamp is better supported in the housing, so that a lamp will break off less quickly at the neck in the event of impact. These standard lamps, table lamps, pendant lamps, or recessed lamps, in combination with a simple sealing ring, can now also be used advantageously in damp or dusty areas without having to provide expensive fixtures where it is difficult to replace the lamp should it break down. An additional advantage is that because the lamp is straight with respect to the collar and the lamp is fixed in the housing with the collar, the lamp is now also straight with respect to the housing.

DETAI LED DESCRI PTI ON OF THE DRAWINGS

The present invention is by no means limited to the embodiments described by way of example and shown in the figures.

Figure 1 shows a cross-section of a lamp in a housing according to an embodiment of the present invention.

A lamp (18), comprising a base (7), a neck (2) and a bulb (1) is mounted in a holder (4). The lamp (18) is a common E27 lamp with a standard base (7) provided with an Edison screw thread (11). The neck (2) of the lamp (18) internally comprises a control of a light source in the bulb (1). The lamp (18) is screwed into the holder (4), which is also internally provided with Edison screw thread (12). The holder (4) comprises a closed lower surface (19), an open upper surface (24) and a cylindrical shell (20). The holder (4) extends in a longitudinal direction, the closed lower surface being transverse to the longitudinal direction. Two contact points are also provided in the holder (4) for electrically connecting the lamp in the holder. A first contact point is located approximately in the middle of the closed lower surface (19) of the holder (4), with a second contact point located on the cylindrical shell of the holder (4). The first contact point here makes a connection with a connection point (9) of the lamp (18) and the second contact point with the shell (7) of the connection of the lamp (18). The first and the second contact point are each connected to a conductor of a cable (8). The holder (4) is provided externally on the cylindrical shell with a screw thread (10) onto which a collar (6) and a retention ring (5) are screwed, the collar (6) being closest to the lamp (18). This collar (6) is movable in the longitudinal direction of the holder (4) in such a way that at an edge (13) of the collar (6) it abuts against the bulb (1) of the lamp (18) or abuts with the bulb (1) of the lamp (18) with a minimal gap and thereby conceals the neck (2) of the lamp (18). The edge (13) of the collar (6) is cup shaped. The collar (6) which now abuts with the neck (2) of the lamp (18) is secured in this position because the retention ring (5) is screwed against the collar (6) .

The collar (6) of the holder (4) is provided with a semicircular recess (14) around the circumference of the collar (6). An annular coil spring (16) is arranged in the recess of the collar (6). A housing (3) is placed over the collar (6), the retention ring (5) and the holder (4). The housing (3) has a closed first end with an opening (17) for passage of the cable (8) and an open second end for receiving the lamp (18). The housing (3) comprises at the second end a semicircular recess (15) for receiving the annular coil spring (16). The circumference of the recess (15) and thus also the housing (3) are dimensioned in such a way that the annular coil spring (16) is releasably clamped in the recesses (14) and (15), whereby the holder (4) via the collar (6) is positioned in a fixed position in the housing (3). The housing (3) conceals the arrangement of the holder (4), collar (6) and retention ring (5) and part of the cable (8).

Figure 2 shows a cross-section of a lamp in a housing according to an alternative embodiment of the present invention.

The lamp (18), holder (4), collar (6) and retention ring (5) are of the same kind as in Figure 1. The housing is a cylindrical body (22) attached with one end to a board (21). The cylindrical body (22) attached to the board (21) has a circular opening for receiving the base (7) of the lamp (18). The cylindrical body (21) has a semicircular recess (23) around the circumference of the cylindrical body. The circumference of the semicircular recess (23) and thus also the cylindrical body (21) are dimensioned such that the annular coil spring (16) is releasably clamped in the recesses (14) and (23), whereby the holder (4) is clamped via the collar (6) is positioned in a fixed position in the cylindrical body (22). The board (21 ) can be mounted in a panel, which can be a partition, wall, or ceiling.

Figure 3 shows a cross-section of a lamp in a ceiling according to yet another alternative embodiment of the present invention. The lamp (18), holder (4) and retention ring (5) are of the same kind as in Figure 1. The collar (6) is different from the embodiments in Figure 1 and Figure 2. The collar (6) is closest to the lamp (18). This collar (6) is movable in the longitudinal direction of the holder (4) in such a way that at an edge (13) of the collar (6) it abuts against the bulb (1) of the lamp (18) or abuts with the bulb (1) of the lamp (18) with a minimal gap and thereby conceals the neck (2) of the lamp (18). The collar (6) which now abuts with the neck (2) of the lamp (18) is secured in this position because the retention ring (5) is screwed against the collar (6). The housing is a board (26). The board (26) is for instance part of a piece of furniture, such as for instance a wall cabinet. The board (26) is, for example, a board of a ceiling, such as a plasterboard, a ceiling tile, or a concrete slab. The board (26) comprises a circular opening (28). The circular opening (28) has a diameter greater than a diameter of the holder (4) and the retention ring (5). The collar (6) comprises a cylindrical or conical volume (29) with an open end for receiving the base (7) of the lamp (18). The volume (29) comprises at its open end an annular projection (27) circumferentially surrounding the volume (29). The annular projection (27) extends transversely to the volume (29). The annular projection (27) has an outer diameter that is at least greater than the diameter of the circular opening (28). The holder (4) is placed through the circular opening (28). The annular projection (27) is positioned against a first side of the board (26). The collar (6) comprises an attachment means for securing the collar (6) in the housing. The attachment means is a spring element (25). The spring element

(25) presses against a second side of the board (26). The second side of the board

(26) lies opposite the first side of the board (26). The spring element (25) is attached to the collar (6) by means of screws (30).