Under-mattress

Abstract: The under-mattress (1) is provided with hollow sections (4, 5) between which a network (14) is stretched. The hollow sections (4, 5) are a special shape, thereby producing the maximum width of network (14). This shape is determined by a polygon, having a face (9) which runs inwards and downwards from the top outside edge (10) of the section (4, 5) and the top edge of which is directly below the network (14), a face (15) which connects to said face (9) at an angle and which runs downwards and/or outwards, and the width of which corresponds to the height of transverse reinforcements (6) which can be connected thereto, and at least a further face which closes the section cross-section. In an under-mattress (1) with flap-up head end (2) and/or foot end (3) provision is also made for a fixed section (7) which has a wall part (8) parallel to the face (9) of section (4).

Description: The present invention relates to an under-mattress, comprising a main frame, which may be provided with adjustable auxiliary frames for head end or foot end, each constituted by longitudinal and transverse frame bars made of hollow sections, and a support network which is stretched at least between two opposite frame bars using means by which the edges of the network are connected to the frame bars in question. Such under-mattress is known from EP-A-130157. The network stretched in the main frame must form a supporting face of suitable rigidity for the top mattress, in such a way that a very comfortable lying position is ensured. However, particularly in the case of a network stretched between the longitudinal bars of the main frame the problem occurs that a major part of said supporting face is taken up by the means for connecting the network to said longitudinal bars. Adjacent to the longitudinal frame bars or the transverse frame bars there is therefore always an area a few centimetres wide which is of much greater rigidity than the network. The disadvantage of this is that the mattress provides an uncomfortable lying surface at the level of those areas. This is felt all the more in the case of two under-mattresses placed next to each other for a double bed, where the longitudinal sections running next to each other in the centre plane together form an even broader, hard uncomfortable strip. All this could be improved by extending the under-mattress by the amount of said hard areas. This is, however, very undesirable for aesthetic reasons, while additional space required in that case is also a disadvantage for the under-mattress. The object of the invention is therefore to produce an under-mattress which provided a more comfortable support. This object is achieved in that the frame bars lying opposite each other and connected to the network have a cross-section in the form of a polygon which is determined at least by an external face which runs inwards and downwards relative to the respective frame from the top outside edge of the frame bar, an internal face which runs downwards relative to the respective frame bar from the top inside edge of the frame bar, and the top edges of which frame bar, being directly below the face of the network, a face running downwards and/or outwards connected to the faces at an angle, and the breadth of which corresponds to the height of transverse reinforcements which can be connected thereto, and at least one further face which closes the section cross-section. The shape of the frame bar cross-section according to the invention provides the possibility of fixing the supported network edges further outwards above the frame bar than was previously possible. Since the face running inwards from the top outside edge of the frame bar is also directed downwards, the part of the network lying above that face still has the capacity to move downwards under load. This means that the actual width of the network over which it gives a comfortable support is greater than in the known under-mattresses, without the total size of the framework having increased. The frame bar has to be capable of taking stresses in the horizontal and in the vertical direction. In the case of the frame bar cross-section according to the invention this is easily possible, since the dimension of the frame bar in both directions can be selected large enough to obtain the desired resistance moment. It is known to hold the network fixed by means of an edge fillet. Such known edge fillets are fixed to the sides of the frame bars facing each other to which the network has to be fixed, or they are integral with said frame bars, e.g. through welding. As already mentioned, this design leads to a substantial reduction in size of the area which is available for the network. According to the invention, a greater effective width of the network can also be obtained in this design through the fact that the edge fillet is a separate, essentially flexible part, this edge fillet is coupled by means of a hook connection to the frame bar and in the fitted state lies on top of a flat top face of the frame bar which is outside the frame bar face running at an angle inwards and downwards. The flexible edge fillet according to the invention obtains its rigidity through the fact that it lies on the top face of the frame bar. Below the edge fillet and the network fixed to it the section continues downwards and inwards, which here again ensures the desired effective width combined with the required strength of the section. The network now lies virtually in the same plane as the top side of the frame, which provides an attractive appearance. In this design of the under-mattress greater flexibility is obtained also as regards manufacture. The known under-mattress is subjected, after being fully assembled, to a finishing treatment, in which it acquires its final colour finish. Network and frame bars are therefore of necessity the same colour. According to the invention, the edge fillets can, however, be manufactured in advance in a desired colour, and the edge fillets can then be hooked into the appropriate frame bars, with the network between them. The hook connection between edge fillets and frame bar has the further advantage that different materials can be selected without problem for these parts. In the case of the known connection the freedom of choice is, of course, very limited in this respect. According to the invention, for example, a high-grade plastic or a high-grade metal can be selected for the edge fillet, which means that an attractive appearance can be ensured. According to a first possible embodiment, provision can be made for the hook connection of the edge fillet to be an edge of the edge fillet which is flanged in a hook shape and grips an outward-facing top edge of the frame bar. The top side of the frame bar is completely covered here, while the outside of it remains visible. All this makes it possible to influence the appearance of the under-mattress further by selecting a specific desired colour combination for edge fillet and frame bar. According to a second possible embodiment, provision can be made for the hook connection of the edge fillet to the frame bar to be formed by a strip of the edge fillet running round the outside of the frame bar and fixed at the bottom side of the frame bar. The frame bar is now completely concealed by the edge fillet. This embodiment makes it possible to select for the frame bar an ordinary metal pipe of sufficiently high strength which need not meet high aesthetic standards. The fixing to the bottom side of the frame bar can be obtained by means of a hook connection. This is not necessary; because the fixing to the bottom side of the frame bar is virtually out of sight, a less attractive appearance is acceptable for it, for example screws or rivets. Provision is preferably made for the cross-section of the frame bars between which the network is stretched to have an external face running from the bottom edge of the frame bar at an angle upwards and outwards to the top edge. The frame bar cross-section thus obtained is approximately triangular in shape, and has the required resistance moments against bending in the horizontal and vertical direction. The fact that the outside of the frame bar tapers downwards produces an unobtrusive appearance. This further increases the impression of compactness of the frame bars, and also of the overall framework. In this connection an attractive embodiment can also be obtained by having at the outside of the upward-slanting external face of the frame bars between which the network is stretched, at a distance from said external face, a second frame bar which is polygonal in cross-section, and the external face of which determines the external face of the main frame. The cross-sections of the two frame bars and of the edge fillet can be matched here in such a way that their surfaces visible at the outside run smoothly into each other. According to another embodiment, provision can be made for this second polygonal frame bar to be essentially the shape of a triangle whose slanting side runs parallel to the slanting outside of the frame bar containing the connection to the network, and the other sides determine the external face and the bottom face of the bar shape. The advantage of the above two embodiments, but in particular of the latter one, is that the positioning of the two frame bars next to and above one another along their facing slanting sides leads to a compact assembly which still has the desired strength properties, thanks to the triangular cross-sections. The upward-slanting duct present in both embodiments between the facing sides of the two frame bars has a beneficial effect in this region on the ventilation of the top mattress and under-mattress lying on top of one another. In particular, where two known mattresses are placed next to each other for a double bed, it is found that moisture and corrosion problems occur in this region near the facing sides of the mattresses. In the case of the known mattresses this region is virtually completely shut off by sections and top mattresses, which means that there can be no ventilation. In the case of the under-mattress according to the invention, this problem can be avoided through ventilation in fact being possible through the above-mentioned ducts. In the case of the two above-mentioned embodiments, the two frame bars can be fixed to each other over their entire length by suitable spacers. In an under-mattress provided with head end and/or foot end adjustable about a horizontal transverse axis, it is, however, possible to provide for the network to be stretched between the longitudinal frame bars of the head end or foot end, and for these longitudinal frame bars to have in cross-section an external face which runs slanting from the bottom edge of the longitudinal bar upwards and outwards towards the top edge, and in the folded-down position for these longitudinal frame bars to lie next to the main frame bars of the main frame which are designed in the shape of a polygonal section whose external face determines the shape of the external face of the main frame, or in the form of a triangle whose slanting side runs parallel to the slanting outside of the frame bar containing the connection to the network, and the other sides determine the external face and the bottom face of the frame bar shape. The under-mattress can be designed in such a way that the frame bars determining the shape of the main frame bars of the main frame are provided on the inside, viewed in cross-section, with a longitudinal slit with undercut top and bottom edge. An advantage of such a design is that objects such as a lighting bracket, table tray and the like can be attached to the under-mattress in the longitudinal slit, in a simple manner and invisible from the side. Finally, in this connection the under-mattress can be designed in such a way that the second frame bar, which determines the shape of the main frame bars of the main frame, is provided on the outside with a recess or groove running in the lengthwise direction, and the under-mattress is provided with supporting legs which each fit with an edge into the lengthwise recess or groove and at a distance away from and opposite said edge have a lip which is staggered inwards relative to the frame bar, and which is at the inside of the frame bar, overlaps the longitudinal slit, and is provided with retaining means which are tensionable and grip in the longitudinal slit of the frame bar. The invention will be explained further below with reference to a number of examples of embodiments as shown in the figures. Fig. 1 shows a view in perspective of an under-mattress according to the invention. Fig. 2 shows a cross-section through a side of the under-mattress. Fig. 3 shows another cross-section according to Fig. 2. Fig. 4 shows a detail of the supporting leg attachment of the under-mattress. The under-mattress shown in Fig. 1 is provided with a main frame 1 and with an adjustable head end 2 and an adjustable foot end 3. Both are supported in a known manner not shown, for example by a gas spring/lever control device. The side frame bars 4, 5 of the head and foot end are connected to each other by transverse frame bars 6 which are bent downwards. A network (not shown) is also stretched between these side frame bars 4, 5. Fig. 2 shows in greater detail the sections 7 and 4 of the main frame 1 and the head or foot end 2, 3, respectively, the head or foot end being shown in the completely folded-down position. The frame bar 4 is provided with a slanting side 27, a slanting side 9 facing a corresponding slanting side 8 of the frame bar 7, and with a outside edge 10. Hooked around this outside edge 10 is the edge fillet 11, which opposite its hook part 12 has teeth 13 running through the network 14. The frame bar 4 also has a recessed part 15 in which the transverse frame bars 6 can be accommodated. Due to the wall parts 8, 9, the frame bar 7 and the frame bar 4 can run next to each other slanting upwards, thus ensuring a compact unit. This design is of a width in cross-section which, as already mentioned, is less than the known design, which gives a more comfortable lying position, in particular where the network is stretched in cross-section between the longitudinal frame bars 4, 5. The frame bar 7 together with the edge fillet forms a curved external surface, which has a beneficial effect on the appearance of this design. According to the variant shown in Fig. 3, the main frame 1 can also be provided with a frame bar 23 with a triangular cross-section. The slanting side 24 thereof runs parallel to the slanting side of frame bar 4. A ventilation duct 25 is present between these sides, for the purpose of reducing moisture and corrosion problems. The triangular frame bar 23 has excellent strength properties as regards bending and torsion. The supporting legs for the under-mattress can be fixed in a suitable manner on the bottom face 26. As shown in Fig. 4, the frame bar 7 has an internal, undercut longitudinal recess 16 and an external longitudinal recess 17. These recesses are intended for the accommodation of a fixing plate 18 and a knob 19 respectively belonging to a supporting leg 20. The plate 18 is connected by means of a screw connection to a lip 21 and can be tightened by the bolt head 22 in the recess 16. The knob 19 is in this case pressed into the recess 17, thereby producing a sturdy leg fastening.

Claims: Under-mattress, comprising a main frame (1), which may be provided with adjustable auxiliary frames (2, 3) for head end or foot end, each constituted by longitudinal (4, 5) and transverse frame bars made of hollow sections, and a support network (14) which is stretched at least between two opposite frame bars (4, 5) using means (11) by which the edges of the network (14) are connected to the frame bars (4, 5) in question, characterized in that, the frame bars (4, 5) lying opposite each other and connected to the network (14) have a cross-section in the form of a polygon which is determined at least by an external face (9) which runs inwards and downwards relative to the respective frame bar (4, 5) from the top outside edge of the frame bar (4, 5), an internal face (27) which runs downwards relative to the respective frame bar (4, 5) from the top inside edge of the frame bar (4, 5) and the top edges of which frame bar (4, 5) being directly below the face of the support network (14), a face (15) running downwards and/or outwards connected to the faces (9, 27) at an angle, and the breadth of which corresponds to the height of transverse reinforcements (6) which can be connected thereto, and at least one further face (10) which closes the frame bar cross-section. Under-mattress according to Claim 1, in which the network is retained by means of an edge fillet (11), characterized in that the edge fillet (11) is a separate, essentially flexible part, this edge fillet (11) is coupled by means of a hook connection (12) to the frame bar (4) and in the fitted state lies on top of a flat top face (10) of the frame bar (4) which is outside the section face (15) running at an angle inwards and downwards. Under-mattress according to Claim 1 or 2, characterized in that the hook connection (12) of the edge fillet (11) is an edge of the edge fillet (11) which is flanged in a hook shape and grips an outward-facing top edge (10) of the frame bar (4). Under-mattress according to Claim 1 or 2, characterized in that the hook connection (12) of the edge fillet (11) to frame bar (4) is formed by a strip of the edge fillet (11) running round the outside of the frame bar (4) and fixed at the bottom side of the frame bar (4). Under-mattress according to one or more of the preceding claims, characterized in that situated at the outside of the oblique upward-slanting external face (9) of the frame bars (4, 5) between which the network (14) is stretched, at a distance from said external face (9), a second frame bar (7, 23) which is polygonal in cross-section, and the external face of which determines the external face of the main frame, is situated. Under-mattress according to Claim 5, characterized in that this second polygonal frame bar (23) is essentially the shape of a triangle whose slanting side (24) runs parallel to the slanting outside (9) of the frame bar (4, 5) containing the connection to the network (14), and the other sides determine the external face (23) and the bottom face (26) of the bar shape. Under-mattress according to Claim 1 provided with a head (2) end and/or foot (3) end adjustable about a horizontal transverse axis, characterized in that the network (14) is stretched between the longitudinal frame bars (4, 5) of the head end (2) or foot end (3), and these longitudinal frame bars (4, 5) are the shape described in Claim 1 and in the folded-down position lie next to the main frame bars of the main frame with a shape according to Claim 5 or 6. Under-mattress according to Claim 5, 6 or 7, characterized in that the frame bars determining the shape of the main frame bars of the main frame are provided on the inside, viewed in cross-section, with a longitudinal slit (16) with undercut top and bottom edge. Under-mattress according to one or more of the preceding Claims 5 to 8, characterized in that the second frame bar (7), which determines the shape of the main frame bars of the main frame, is provided on the outside with a recess or groove (17) running in the lengthwise direction, and the under-mattress is provided with supporting legs (20) which each fit with an edge (19) into the lengthwise recess or groove (17) and at a distance away from and opposite said edge have a lip (21) which is staggered inwards relative to the frame bar (7), and which is at the inside of the frame bar (7), overlaps the longitudinal slit (16), and is provided with retaining means (18) which are tensionable and grip in the longitudinal slit (16) of the frame bar (7).

Inventors: DE LA HAYE CORNELIS FRANCISCUS, HAS PETER VICTOR, NIJSEN ANDREAS LOUIS, DE LA HAYE, CORNELIS FRANCISCUS, HAS, PETER VICTOR, NIJSEN, ANDREAS LOUIS
Applicants: AUPING BV, AUPING B.V.
Application year: 1990
Main classification: A47C19
IPC codes: A47C20, A47C19