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Title:
HANG STANDARD AND STORAGE SYSTEM INCLUDING THE HANG STANDARD
Document Type and Number:
WIPO Patent Application WO/2021/221556
Kind Code:
A1
Abstract:
A hang standard (1, 1a), for mounting vertically and connecting with cantilevered brackets (11), is elongated and has an approximately U-shaped cross- section with a front portion (2, 2a) and two rearwards extending leg portions (3, 3a). The front portion (2, 2a) comprises a plurality of slots (4, 4a) located in a recess (5, 5a) between first and second protruding portions (6, 6a), which are located on first and second side of the slots (4, 4a). The recess (5, 5a) is laterally continuous from the first to the second protruding portion (6, 6a) and over two columns of slots (4, 4a). In some embodiments there is a transition portion (7, 7a) which extends into a protruding portion (6, 6a) with an outer lateral wall (19, 19a) facing away from the front portion (2, 2a) and an inner lateral (20, 20a) wall facing towards the front portion (2, 2a), and the outer (19, 19a) and inner (20, 20a) lateral walls together comprise a double layer of sheet metal. A storage system includes a plurality of hang standards (1, 1a), mounting means, brackets (11), and storage means supported by the brackets (11).

Inventors:
NILSSON PETER (SE)
RINGENHAG TOBIAS (SE)
Application Number:
PCT/SE2021/050396
Publication Date:
November 04, 2021
Filing Date:
April 29, 2021
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
ELFA INT AB (SE)
International Classes:
A47B96/14; A47B96/06
Foreign References:
GB2169791A1986-07-23
US5110080A1992-05-05
JPS4618350Y11971-06-26
JPS51123123U1976-10-05
Other References:
See also references of EP 4142542A1
Attorney, Agent or Firm:
INDUSTRIPATENT I VÄXJÖ AB (SE)
Download PDF:
Claims:
Claims

1. A hang standard (1 ) for mounting vertically in a storage system and connecting with cantilevered brackets (11) and the like, the standard (1) being elongated and having an approximately U-shaped cross-section with a front portion (2) and two rearwards extending leg portions (3), the front portion (2) comprising a plurality of slots (4, 4a) as connection points and being located in a recess (5) between first and second protruding portions (6), located on first and second side of the slots (4), respectively, characterized by the recess (5) being laterally continuous from the first to the second protruding portion (6) and over two columns of slots (4).

2. A hang standard (1 ) for mounting vertically in a storage system and connecting with cantilevered brackets (11) and the like, the standard (1) being elongated and having an approximately U-shaped cross-section, formed in a single piece from a strip of sheet metal, with a front portion (2) and two rearwards extending leg portions (3), the front portion (2) comprising a plurality of slots (4, 4a) as connection points, wherein between the front portion (2) and each of the leg portions (3) there is provided a transition portion (7) characterized by each transition portion (7) extending into a protruding portion (6) which has an outer lateral wall (19) facing away from the front portion (2) and an inner lateral wall (20) facing towards the front portion (2), and the outer (19) and inner (20) lateral walls together comprise a double layer of the sheet metal.

3. A hang standard (1a) for mounting vertically in a storage system and connecting with cantilevered brackets (11) and the like, the standard being elongated and having an approximately U-shaped cross-section, with a front portion (2a) and two rearwards extending leg portions (3a), the front portion (2a) comprising a plurality of slots (4, 4a) as connection points and being located in a recess (5), characterized by an outwards extending longitudinal flange (22) at the rear end of each of the leg portions (3a).

4. A hang standard (1 , 1a) according to claim 1 or claim 2, characterized in that the connection points (4, 4a) are arranged between the protruding portions (6, 6a).

5. A hang standard (1 ) according to claim 1 or claim 2, wherein the section of the rearward extending leg portions (3, 3a) is narrower than the front portion (2, 2a), thereby forming a ledge (18, 18a) at the transition portion (7, 7a) between each leg portion (3, 3a) and each protruding portion (6, 6a).

6. A hang standard (1 ) according to claim 1 or claim 2, wherein the protruding portions (6, 6a) and the front portion (2, 2a) together form an undercut recess (5, 5a).

7. A hang standard (1) according to claim 1 or claim 2, wherein an inner lateral wall (20, 20a) of each protruding portion (6, 6a) is slanted.

8. A hang standard (1 , 1a) according to claim 7, wherein each inner lateral wall (20, 20a) is arranged with angle of less than 15° to a respective outer lateral wall (19, 19a) of the protruding portion (6, 6a).

9. A hang standard (1 ) according to any of the preceding claims, wherein a longitudinal rib (8) is provided in the bottom part of the recess (5) between the columns of slots (4, 4a).

10. A hang standard (1) according to claim 9, wherein the longitudinal rib (8) is embossed in the front portion (2) between the columns of slots (4, 4a).

11. A hang standard (1) according to claim 9, wherein the longitudinal rib (8) is provided by parallel bendings of the front portion (2) between the columns of slots (4, 4a).

12. A hang standard (1, 1a) according to any of the preceding claims, wherein the standard (1 , 1a) is manufactured from a single sheet of folded metal.

13. A hang standard (1, 1a) according to any of the preceding claims, wherein engagement devices (9, 9a) are arranged at the rearwards extending leg portions (3, 3a) for cooperation with mounting means (13), e. g. on a wall (10).

14. A storage system including a plurality of hang standards (1, 1a) according to any of claims 1 to 13, mounting means (13), for interaction with each of the standards (1 , 1a), arranged on a wall (10), brackets

(11 ) connected with the standards (1 , 1 a), and storage means supported by the brackets (11 ).

Description:
HANG STANDARD AND STORAGE SYSTEM INCLUDING THE HANG

STANDARD

Field of the invention

The present invention relates to a hang standard for mounting vertically in a storage system and connecting with cantilevered brackets and the like, the standard being elongated and having an approximately U-shaped cross-section with a front portion and two rearwards extending leg portions, the front portion comprising a plurality of slots as connection points and being located in a recess between first and second protruding portions, located on first and second side of the slots, respectively.

The invention also relates to a hang standard for mounting vertically in a storage system and connecting with cantilevered brackets and the like, the standard being elongated and having an approximately U-shaped cross-section, formed in a single piece from a strip of sheet metal, with a front portion and two rearwards extending leg portions, the front portion comprising a plurality of slots as connection points, wherein between the front portion and each of the leg portions there is provided a transition portion.

The invention further relates to a hang standard for mounting vertically in a storage system and connecting with cantilevered brackets and the like, the standard being elongated and having an approximately U-shaped cross-section, with a front portion and two rearwards extending leg portions, the front portion comprising a plurality of slots as connection points and being located in a recess. In a fourth aspect, the invention relates to a storage system including a plurality of standards as above.

Background

WO201 9/083632 A1 discloses a wall-mounted storage system, which comprises a number of hang standards for vertical mounting on a wall or the like. The hang standards provide a support for cantilevered brackets, which in their turn support various storage components, such as shelves, baskets, drawers, etc. Each of the brackets utilizes slots in a single column of slots in the hang standard for inserting hooks in order to hang a bracket therein. The hang standard has a cross- section where the columns of slots are recessed, in order to obtain a visually attractive appearance, the slots being at least partly obscured by protruding portions. Pre-existing brackets, with attachment hooks arranged in parallel, are not compatible with the disclosed hang standards.

The above-mentioned document also discloses a couple of wall-standards which have a generally U-shaped cross-section. Pre-existing brackets, with double attachment hooks are compatible with such hang standards, but a drawback is that the hang standards have a limited ability to support heavy loads, i. a. since their bending stiffness is limited.

Summary

It is an object of the present invention to solve, or at least mitigate, parts or all of the above-mentioned problems. To this end, there is provided a hang standard as mentioned initially, wherein the recess is laterally continuous from the first to the second protruding portion and over two columns of slots.

The technical effect of this hang standard is that it has a recess for the connection points for the brackets, in order to conceal them or at least make them less conspicuous. It works well with different brackets for shelves, drawers, and the like, where such brackets have been on the market for several years. Hence the disclosed hang standard is combinable with components that the end customer may already have, or with components that are already in stock at the retailers.

In another aspect of the invention, there is provided a hang standard as mentioned initially, wherein each transition portion extends into a protruding portion which has an outer lateral wall facing away from the front portion and an inner lateral wall faces towards the front portion, and the outer and inner lateral walls together comprise a double layer of the sheet metal.

Hereby the bending stiffness of the hang standard is increased, in particular as the cross-section of the hang standard bears a resemblance to an I-beam. This will provide an increased second moment of area. The high bending stiffness will result in a high load-carrying ability with a maintained shape of the hang standard, both as seen in its longitudinal direction as in its cross section. In a third aspect of the invention, there is provided an outwards extending longitudinal flange at the rear end of each of the leg portions.

Hereby the bending stiffness of the hang standard is increased. Another advantage is that the flanges, being arranged to be parallel with, and bear against, a wall whereon the hang standard may be mounted, do not bear against the wall with any sharp edges. Such edges could damage the surface of the wall, e. g. paint or wallpaper.

In one embodiment of the present disclosure, the connection points of the hang standard are arranged between the protruding portions.

Hereby a contribution to a visually pleasing appearance may be made.

In another embodiment the section of the rearward extending leg portions is narrower than the front portion, thereby forming a ledge at the transition portion between each leg portion and each protruding portion.

Hereby a covering screen or board may be attached between two hang standards by sliding, clamping, or snapping it behind the longitudinal ledge on the respective hang standard.

In one embodiment the protruding portions and the front portion together form an undercut recess.

Hereby the recess does not only conceal the connection point from view, it may also be utilized for snap fastening of various components included in the storage system.

In one embodiment an inner lateral wall of each protruding portion is slanted.

Hereby the undercut recess is provided.

In a further embodiment each inner lateral wall is arranged with angle of less than 15° to a respective outer lateral wall of the protruding portion.

Hereby, with a limited angle between the outside and inside lateral walls of the protruding portion, the bendingbending stiffness of the hang standard as a whole is increased e. g. in comparison with a hang standard without protruding portions. In some preferred embodiments the angle is 3-12°, and preferably 10°.

In a still further embodiment, a longitudinal rib is provided in the bottom part of the recess between the columns of slots.

Hereby the fit of pre-existing brackets in the disclosed hang standard may be exact or at least improved. The disclosed hang standard may be manufactured in a sheet metal with a limited thickness, and the provision of a longitudinal rib between the columns of slots may set the distance between the back side and the front side of the front portion longer than the actual thickness of the sheet metal. From back side at the bottom of the slots, on the one hand, to the front side of the front portion at the longitudinal rib on the other, the distance will be greater than the actual thickness of the metal. The difference will be approximately equal to the height of the rib. Hence it is possible to make the thickness of a thinner plate appear as a thicker plate that was used previously in connection with pre-existing brackets.

In a further embodiment, the longitudinal rib is embossed in the front portion between the columns of slots.

Hereby one possibility of providing the rib is disclosed.

In another embodiment the longitudinal rib is provided by parallel bends of the front portion between the columns of slots.

Hereby another option for the provision of the rib is disclosed.

In a further embodiment the standard is manufactured from a single sheet of folded metal.

In a still further embodiment, engagement devices are arranged at the rearwards extending leg portions for cooperation with mounting means, e. g. on a wall.

Hereby various options for mounting the hang standard in an upright position on a wall may be provided, in addition to the prior art option of arranging fixing means, such as a screw, through the front portion and into the wall. In a third aspect of the disclosure the storage system includes a plurality of hang standards, mounting means, for interaction with each of the standards, arranged on a wall, brackets connected with the standards, and storage means supported by the brackets.

It is noted that embodiments of the invention may be embodied by all possible combinations of features recited in the claims. Further, it will be appreciated that the various embodiments described for the device are all combinable with the method as defined in accordance with the second aspect of the present invention, and vice versa.

Brief description of the drawings

The above, as well as additional objects, features and advantages of the present invention, will be better understood through the following illustrative and non limiting detailed description of preferred embodiments of the present invention, with reference to the appended drawings, where the same reference numerals will be used for similar elements, wherein:

Fig. 1 is a diagrammatic view in perspective of a hang standard according to the disclosure;

Fig. 2 is a planar view of the hang standard according to Fig. 1 ;

Fig. 3A is a side view of the hang standard according to Fig. 1 mounted on a wall, with a bracket supporting a load;

Fig. 3B is a diagrammatic view in perspective of a rail for mounting the hang standard on a wall;

Fig. 4 is a cross sectional view of the hang standard according to fig. 1 ;

Fig. 5A is a diagrammatic view in perspective of another embodiment of the hang standard;

Fig. 5B is a planar view of the hang standard according to Fig. 5A; and Fig. 5C is a cross sectional view of the hang standard according to Fig. 5A.

All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the embodiments, wherein other parts may be omitted.

Detailed description of the exemplary embodiments

Fig. 1 illustrates a hang standard 1 according to the invention. The hang standard 1 may be comprised as one among many components in a storage system. Several hang standards 1 may be arranged side by side, at suitable distances from one another, vertically, e. g. on a wall. The hang standards 1 are designed to interact with brackets, which in their turn carry loads and/or other components in the storage system, or directly with other components of the storage system.

The hang standard 1 has a generally U-shaped cross-section with a forwardly facing front portion 2 and two rear leg portions 3, as seen when the hang standard 1 is mounted vertically on a wall. The hang standard 1 may be formed from a single piece of sheet metal by punching and bending, in several steps, thereof.

The front portion 2 is provided with a number of connection points for brackets at different heights, to allow for a selection of the connection point for each bracket used in the system. In the embodiment disclosed in Fig. 1, the connection points are slots 4 arranged in two columns next to one another. One of the columns is not visible in Fig. 1 but is clearly shown in Fig. 2. Each slot 4 is arranged next to an identical slot 4 in the other column, thereby providing that the slots 4 are arranged in pairs at different heights. The shown hang standard is rather short for illustrative purposes, having only six slots in each row. Usually hang standards have several tens of slots in each row.

The front portion 2, with the columns of slots 4, is arranged in a recess 5, which is surrounded by protruding portions 6 on each side of the front portion 2. The protruding portions 6 extend forwards from the leg portions 3 via a connecting transition portion 7 on each side of the hang standard 1. The protruding portions 6 extend slightly outwards from the leg portions 3 at the transition portions 7. In other words, the outer transversal dimension of the hang standard 1 is wider at the protruding portions 6 than at the leg portions 3.

Each protruding portion 6 has an outer wall and an inner wall which will be described in detail in connection with Fig. 4. It may be noted that the protruding portions 6 are generally double-walled and formed by bending of the sheet metal making up the hang standard 1.

A longitudinal rib 8, best seen in Fig. 2, is provided between the two columns of slots 4. The rib 8 is a narrow area, slightly raised from the surface of the front portion 2. It may be provided by embossing, stamping, bending, etc. of the sheet metal forming the front portion 2. Alternatively, an additional metal strip may be added to make up the rib, e.g. attached by gluing or welding. The forming of the longitudinal rib 8 may takes place before the formation of the hang standard 1 by bending or as an intermediate step in the formation process.

The function of the longitudinal rib 8 is mainly to make the front portion 2 appear thicker for the purpose of connecting brackets thereto. Brackets that were originally designed to have an optimal fit on hang standards manufactured from a thicker sheet metal may have a correct fit, without play, thanks to the provision of the rib 8. The material thickness in the illustrated case is typically in the range from 1.2- 1.8 mm, preferably about 1.6 mm.

The bracket is connected to the hang standard 1 by insertion of hooks into the slots 4. The hooks are each open downwards with a width of the opening closely corresponding to the thickness of the sheet metal. Flence, they will come into contact with the outer face of the front portion 2, between the columns of slots 4, as well as with the rear side of the front portion 2, at the lower end region of the slots 4. In the absence of a rib 8, the distance between the outer face and the inner side of the front portion 2, at the respective areas of contact, will correspond to the thickness of the sheet metal. If the thickness of the sheet metal closely matches the opening width of the hook, the fit will be good without play. If the sheet metal is thinner, the distance between the outer face and the inner side of the front portion 2, at the respective areas of contact, may be too small and the bracket may appear loose. The rib 8 provides a sufficient elevation for matching the distance between the two areas of contact on the hang standard 1 with the width of the hook opening on the bracket.

In at least one position, as shown in the schematic view of Fig. 1 , the leg portions 3 may be provided with an engagement device 9. The engagement device 9 disclosed in Fig. 1 is a series of sockets, that are shaped to correspond with a horizontally arranged rail, which will be disclosed in further detail below in connection with Fig. 3B. the sockets 9 will allow the hang standard 1 to be hung from a rail and to be slid sideways into any exact, desired position, when the storage system is mounted.

Fig. 3A shows a side view of the hang standard 1 hanging from a horizontal rail 13, which is mounted on a wall 10. The cross-section of the rail 13 correspond with the shape of the sockets 9, and the hang standard 1 is hanging vertically. A load carrying, cantilevered bracket 11 is attached to at least one of the connection points provided on the front portion 2. A load 12, e. g. a basket or a drawer is arranged to be supported by the cantilevered bracket 11. Since the size of the load is unpredictable within reasonable limits, and the distribution of the load in the box is unpredictable as well, the load is symbolized by the arrow L in Fig. 3A, which is drawn from an arbitrary mass center at a distance from the connection point of the bracket 11 in the hang standard 1. Since a distance between the mass center and the connection point in the hang standard 1 always has to be taken into account, the hang standard 1 has to be designed with a resistance to the resulting torque, i. e. with a certain bending stiffness. Otherwise the torque acting on the hang standard 1 may lead to a bending thereof, with the consequence that the hang standard may not hang snugly against the wall. At the same time, a low weight and a limited material consumption are desirable. The disclosed design of the hang standard 1 take all these aspects into account.

Fig. 3B shows the rail 13 in perspective. As seen in Fig. 3A, it is intended for horizontal mounting on a wall 10. As seen in the mounted position, it has an upper 14a and a lower 14b flange. The upper flange 14a is provided with at least one pair of notches 15. The notches 15 are separated by a distance which corresponds to the distance between the leg portions 3 on the hang standard 1. Screw holes 16 are provided for the arrangement of fixing means therein. At each outer end of the rail 13 there is an end tab 17.

The hang standard 1 may be mounted on the horizontal rail 13 by lowering in a vertical direction at the position of the notches 15. The leg portions 3 will each slide in a notch 15, until the lower flange 14b has reached its position in the engagement device 9. At this point, the hang standard 1 may be slid in the horizontal direction, so that the upper flange 14a enters the engagement device 9 sideways. When both the upper 14a and the lower 14b flanges are in their respective positions, the hang standard 1 cannot be accidentally dismounted, even when it is subjected to an upwards or outwards directed force. The end tabs 17 will act as stops to keep the hang standard 1 from sliding off the rail 13 sideways.

Fig. 4 discloses the cross section of the hang standard 1 in detail. The leg portions 3 are straight and extend rearwards towards the wall, as seen in a mounted position. The distance between the leg portions 3 approximately correspond to the width of the front portion 2, thereby providing the hang standard 1 with an approximately U-shaped cross-section, comprising the front portion 2 and the leg portions 3. At the forward end of the respective leg portion 3, as seen in a mounted position, there is a transition portion 7. From each transition portion 7 a protruding portion 6 extends forward, together framing the front portion 2 on both sides thereof.

Each protruding portion 6 has an outer wall 19 and an inner wall 20, as mentioned briefly above. In the disclosed example of Fig. 4, the outer wall 19 is approximately parallel with the leg portions 3, but preferably arranged at a distance therefrom. Flence the hang standard 1 is wider across the protruding portions 6 than across the leg portions 3.

Each inner wall 20 is arranged at an angle to the adjacent outer wall 19. The angle is sharp, preferably no more than 15°, more preferably in the range of 3-12°, and in the example shown in the figures the angle is approximately 10°. The slanting inner walls 20 form the recess 5 with the front portion 2. The recess 5 will hereby be slightly undercut, which may make it suitable for snap fastening of various components in the storage system. If brackets 11 of a conventional type are connected to the hang standard 1 , the slanting inner walls 20 may also contact the lateral sides of the brackets 11 , thereby providing additional stability to the mounted brackets.

In addition thereto, the small angle between the outer 19 and the inner 20 walls may make the protruding portion 6 perform as if it were double-walled. This may provide the hang standard 1 with properties similar to those of an I-beam. Its flexural rigidity and bending stiffness will be greater than those of a hang standard with a basic U-shape according to the prior art.

In the middle of the front portion 2, the longitudinal rib 8 is arranged between the columns of slots 4 (not shown in Fig. 4), as described above. In Fig. 4 it is clearly visible that the rib 8 comprises two parallel bends 21 of the sheet metal, resulting in the raised, longitudinal rib 8.

At each transition portion 7 between the leg portion 3 and the outer wall 19 of the protruding portion 6, a ledge 18 is formed, due to the fact that the protruding portion 6 extends laterally outwards to a higher degree than the leg portion 3. The ledge 18 may be utilized for holding a screen or board in place between two hang standards 1 that are arranged next to one another, for instance. The screen or board may be slid in place from above or it may be snapped into its position by a slight bending thereof. As another alternative, the screen or board may be held in its position with one lateral edge next to a first hang standard 1 , while a second hang standard 1 is slid sideways, along a rail 13, into its final position next to the other lateral edge of the screen or board. If needed, the screen or board may be utilized for covering the rails 13, other rails, electricity wires, pipes for water or heating etc.

Fig. 5A-5C discloses another embodiment 1a of the hang standard. Like the embodiment described above, the hang standard 1a has a front portion 2a, forming an inner surface of a recess 5a. The front portion is provided with slots 4a, which are rectangular in the embodiment shown in fig 5A.

The outer 19a and inner 20a walls of the protruding portions 6a are similar to those of the previously described embodiment, and transition portions 7a are provided between the protruding portions 6a and leg portions 3a. Ledges 18a are formed at the transition portions 7a. Engagement devices 9a, in the form of sockets, for engagement with a (not shown) horizontal rail are provided in the leg portions 3a, as described above, as seen in fig 5C

In the embodiment of 5A, the leg portions 3a are provided with longitudinal flanges 22 at their rear ends, for abutment against a wall, when the hang standard 1a is arranged in its mounted position. The longitudinal flanges 22 extend laterally outwards from the centre of the hang standard 1 a. When the hang standard 1 a is mounted, they will bear against the wall, which may be advantageous, as they have no potentially sharp edges in contact with the wall, thereby reducing the risk of damage to the surface of the wall.

Further, the provision of the longitudinal flanges 22 may increase the flexural rigidity of the hang standard 1a, so that higher loads may be carried by the hang standard 1a without the risk of damage thereto. In fact, the strength of the hang standard 1a may be due to the fact that its section is similar to that of an I-beam.

In Fig. 5B, it may be clearly seen that the slots 4a are rectangular, i. e. with a lower edge 23 extending along a straight line. When a bracket 11 etc. is mounted in such a slot 4a, the load 12 carried by the bracket 11 may be distributed over all of the lower edge 23 thereby increasing the load carrying capabilities of each slot 4a and minimizing the risk of deformation thereof. The risk of deformation of the hang standard 1a as a whole may also be reduced. As a further embodiment, rectangular slots 4a may be provided in the hang standard 1 described initially.

It may also be seen in Fig. 5B that there is no rib 8 between the columns of slots 4a. The provision of a rib 8 may be seen as optional and depending on the thickness of the sheet metal used for the manufacture of the hang standard 1a. In some embodiments a thinner sheet metal may be used, and a rib 8 may be provided as a feature in hang standards 1a, which otherwise have the rest of the features of the embodiment shown in Fig. 5A-5C. If a rib 8 is provided, a sheet metal with the thickness of 1 ,2-1 ,5 mm may be used, whereas if a sheet metal with the thickness of 1,6 mm and over is used, the rib 8 may be dispensed with.

In order to fully illustrate the disclosed embodiment, a cross sectional view is shown in Fig 5C. The features distinguishing between this embodiment and the embodiment of Fig. 4 is, as mentioned above, the longitudinal flanges 22 and the absence of the rib 8 in Fig. 5C. These distinguishing features may be separated from their respective embodiments and may be freely combined with the other features in the explicitly disclosed embodiments, in order to form further embodiments.

As illustrated in fig 5C, the protruding portions may protrude a distance df in front of the front portion 2a. Typically, this distance may be in the range 4-10 mm, in the illustrated case 6.5 mm. The longitudinal flanges 22 may extend a distance dl laterally, typically in the range 2-6 mm, and in the illustrated case about 3.0 mm. The depth dr of the hang standard between the front portion 2a and the wall or the like may typically be 14-22 mm, in the illustrated case about 19 mm. This gives a sufficient strength with some margins in the case where the goods thickness of the sheet metal is about 1.6 mm.

The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.

In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.