The present Invention relates to a sliding door or sliding window with at least two wings which are slidable in relation to each other and which can slide parallel to each other behind and in front of each other in two different planes. In what follows, everything that is said about a sliding door, shall also apply to a sliding window.

The expression that the wings are slidable in relation to each other, does not mean that the wings necessarily have to be separately slidable, but also comprises the situation whereby, for example, one wing is fixed and the other wing is slidable in relation to the fixed wing.

The wings of the sliding door are composed of profiles made from aluminium or the like which together from a frame with vertical mullions and horizontal transoms in which a panel made of glass or the like can be fitted.

In this known type, of sliding doors or sliding windows the wings overlap each other with a so-called central mullion of each of the wings, whereby seen from the outside the central mullion of one wing is hidden behind the central mullion of the other wing. The design of the sliding door is thus that between the sides of the overlapping mullions facing each other there is a nominal transverse distance of, for example, 12 millimetres to have sufficient space to put sealing profiles between the central mullions to provide sealing against wind and rain. The transverse distance is measured perpendicular to the sliding direction, more specifically perpendicular to the plane of the panels of the wings.

The sealing profiles are provided in the sliding direction of the wings of a laterally protruding lip at a distance of the sides of the central mullions facing each other, whereby the sealing profiles, when a sliding door is closed, hook behind each other with their lips and press a seal on the other central mullion to form a seal over the entire height of the central mullions.

In the design, sealing profiles are chosen with a thickness smaller than the aforementioned specified nominal transverse distance between the central mullions in closed condition.

For a nominal transverse distance of typically 12 millimetres, for example, sealing profiles are chosen with a thickness of 8 millimetres and lips which in the nominal closed condition of the sliding door hook behind each other with a play of, for example, 3 millimetres.

This results, departing from the nominal closed condition, in a restricted freedom of movement in the transversal direction of the central mullions in relation to each other, which is necessary to compensate for, for example, manufacturing tolerances or to allow movements in relation to each other as a result of wind or movements in relation to each other as a result of the differential extension or shortening of the central mullions on the outside of the sliding window in relation to the inside.

This can be the result, for example, of a difference in temperature between inside and outside, with the consequence that the central mullions can sag outward or inward depending on whether the temperature in the summer outside is greater than inside or vice versa in the winter is lower than inside.

Because of the sag the movement of the central mullions in. relation to each other is greater midway the central mullions than at the top and bottom.

However, because of the specific shape and dimensions of the sealing profiles, freedom of movement of the central mullions in relation to each other in a transversal direction is more restricted, whereby the transverse distance between the sides of the central mullions facing each other in the given example of dimensions is restricted between a minimum required transverse distance of Θ millimetres to a maximum permitted transverse distance of 15 millimetres.

In case of greater sagging it is possible that the transverse distance between the central mullions is greater midway than the maximum permitted transverse distance while the transverse distance between the central mullions toward the top and the bottom can diminish to below this maximum permitted transverse distance, such that when closing the sliding door inevitably the lips of the sealing profiles hit each other at a certain height resulting in possible damage.

Furthermore, in that case the lips of the sealing profiles do not hook into each other midway but next to each other, with the consequence that even when the door is closed there is an opening midway between the central mullions along which rain and wind have free rein.

In case of temperatures whereby the sag of the central profiles means the transverse distance can be smaller than the required minimum transverse distance, it is possible that when closing the sliding door a sealing profile of the central mullion of one wing hits the outer edge of the central mullion along the outside perimeter of the other wing, such that the sliding door can no longer be closed and result in possible serious damage.

The purpose of the present invention is to offer a solution for one or more of the aforementioned and other disadvantages. To this end, the invention relates to a sliding door or sliding window with at least two wings in the form of a frame with mullions and transoms in the form of profiles, whereby the wings are slidable in relation to each other behind and in front of each other in two different parallel planes and Whereby when the door is in a closed condition the so-called central mullions of both wings overlap with two sides facing each other, characterised in that on these sides of the central mullions facing each other two guide components are provided which together form a first guide, respectively a first guide component on one of the central mullions and a second guide component on the other central mullion that co-operates with the first guide component, whereby each of these guide components is provided with a tooth and slot which, when the sliding door or sliding window is in a closed condition, fit into each other in such a way that they keep the central mullions with the sides facing each other at a nominal transverse distance from each other and whereby the teeth are provided with a wedge-shaped end with a bevelled guide surface that defines a narrowing entrance toward the slot for the tooth of the other guide component when the transverse distance between the central mullions is greater than the nominal transverse distance when closing the sliding door or sliding window.

For a nominal transverse distance of, for example, 12 millimetres and thus a thickness of the guide elements of approximately 12 millimetres, the teeth of the guide elements when closing the sliding door will still be able to hook into each other up to a maximum transverse distance of, for example, 21 millimetres to ensure sufficient guidance between the teeth in relation to each other.

When closing the sliding door in that case, the teeth will come into contact with each other with their bevelled sides before the sliding door has reached its closed position and the teeth, when closing the sliding door further, will automatically guide the central mullions in the transversal direction toward, each other to a situation in which the door has reached its closed position in which the central mullions overlap each other and the teeth grip into the slots of the guide components, corresponding with a situation in which the transverse distance between the central mullions approximately corresponds with the specified nominal transverse distance of, for example, 12 millimetres. An advantage of such a first guide according to the invention is therefore that the transverse distance when closing the sliding door is automatically reduced to a transverse distance whereby collisions between the lips of the sealing profiles are avoided before these lips hook into each other.

Another advantage of the invention linked to this is therefore that the maximum permitted transverse distance between the central mullions of, for example, 21 millimetres in the event of the invention is greater than the maximum permitted transverse distance of, for example, 15 millimetres with a conventional sliding door without a first guide according to the invention. As the sag is the greatest midway the central mullions, it is preferential to fit the first guide on this level.

The invention also relates to a second guide that can be applied together with the first guide or alone. This second guide is fitted with a third guide component on one of the two central mullions which is provided with a wedge-shaped end with a bevelled guide surface turned away from the central raullion in question which descends in the direction of the outer edge of the wing in question and which when closing the sliding door or sliding window forms a guide for the other central mullion to push the two central mullions away from each other in the transversal direction when the transverse distance between the central Bullions when closing is smaller than the specified nominal transverse distance.

That offers the advantage that when closing the sliding door collisions can be avoided between a sealing profile on a central mullion with the other central mullion when the transverse distance were to become smaller than the aforementioned minimum transverse distance between the profiles. Thanks to the second guide the central mullions are pushed away from, each other if the transverse distance in relation to each other is too small before a sealing profile is about to hit the central mullion of the other sealing profile.

This provides the advantage that consequently the central mullions in the transversal direction can come much closer to each other, for example, to a transverse distance of 1 millimetre without any danger of hitting each other and the arising damage or without danger that the sliding door can no longer close. If both guides are applied together, the consequence is that much greater inward or outward sag is permitted than in the case without, whereby the transverse distance between the central mull.ions may vary between 1 and 21 millimetres for a specified nominal transverse distance of 12 millimetres, to be compared with a much smaller permitted margin of 8 to 15 millimetres in the event without these, guides for a same nominal transverse distance of 12 millimetres.

The invention also relates to a first or a second guide or a combination thereof for application in a sliding door or sliding window as aforementioned.

With the intention of better showing the characteristics of the Invention, a few preferred embodiments of a sliding door according to the invention and guides applied thereby are described hereinafter by way of an example, without any limiting nature, with reference to the accompanying drawings, wherein: figure 1 schematically shows a frontal view of a sliding door according to the invention in a nominal closed condition;

figure 2 shows a cross-section according to line II- II in figure 1;

figures 3 and 4 show the same cross-section as that, of figure 2, but for two different possible situations when closing the sliding door; figure 5 shows a cross-section according to line V-V in figure 1;

figure 6 shows a perspective view of the part indicated in figure 5 with F6;

figure 7 shows the cross-section of figure 5, but for another position of the sliding door when closing the sliding door;

figure 8 shows a cross-section according to line VIII- VIII in figure 1;

figure 9 shows a perspective view of the part indicated in figure 8 with F9;

figure 10 shows the cross-section of figure 8, but for another position of the sliding door when closing the sliding door;

figure 11 shows a variant embodiment whereby the pieces of figures 6 and 9 are merged into two components;

figure 12 shows a perspective view of a practical embodiment of the pieces of figure 11 but in a mounted situation for a lift-slide door;

figure 13 shows the view of figure 12 in another situation.

In figure 1 a frontal view is shown by way of example of a closed sliding door 1.

The sliding door is made up of a fixed frame 2 to be built into a wall or the like and in this case with two fitted slldable wings 3 with a frame that is made up of essentially the same profiles from aluminium or the like in the form of vertical mullions 4 connected by horizontal transoms.

The profiles are fitted with & slot 6 that extends along the inside edge 7 of the wings 3 and in which a panel of glass or the like can be fitted.

The wings 3 are slidable in relation to each other in two different parallel planes behind and in front of each other according to a sliding direction X-X' , whereby when the sliding door 1 is in a closed condition as shown in figure 1, the central mullions 4a and 4b overlap from a frontal view, one behind the other. In this situation the central mullions 4 are opposite each other with two sides 8a and 8b facing each other with a transverse distance A between both sides 8 measured in the transversal direction Y-Y' as shown in figure 2 in which a nominal design situation is shown with a specified nominal transverse distance A of, for example, 12 mm.

Along the outer edge 9 of the wings 3 the central mullions 4 are fitted with a cover plate 10. On the sides 8 facing each other, the central mullions 4a and 4b are provided with a sealing profile 11 with a thickness B that is smaller than the nominal transverse distance A and, for example, amounts to 8 mm for a nominal transverse distance of 12 mm. Along the outside of a vertical edge 12, the sealing profiles 11 are provided with a lip 13 which according to the sliding direction X-X' extends in the direction of the sealing profile 11 on the other central mullion 4 and is located at a distance from the edge 8 which is approximately the same as the thickness of the sealing profile 11.

The sealing profiles 11 are provided with a seal 14 on the aforementioned edge 12.

In the closed situation on figure 2 the lips 13 grip behind each other and thereby press the aforementioned seal 14 of the sealing profile 11 on the other central mullion 4 against the edge 12 to provide a seal between the central mullions 4a and 4b.

The sealing profiles 11, conventionally, extend across the entire height of the central mullions,

In the case of the invention the sealing profiles 11 are locally interrupted, for example, in the middle, to make room for two guides 15 and 16 according to the invention, one above the other.

In the event the circumstances depart from the nominal design circumstances, for example, in case of a greater or smaller difference in temperature between inside and outside, it may happen that the transverse distance between the central mullions 4 is greater or smaller than the nominal transverse distance A, as a result of warping of the central mullions 4 by a differential contracting or shrinking between inside and outside.

Figure 3 shows a situation whereby the transverse distance has reached a minimum permitted value B which is the same as the thickness B of the sealing profiles 11.

In case of an even smaller transverse distance it can indeed happen that the lips 13 hit the inside edge 7a and or 7b of the other central mullion 4a and/or 4b when closing the sliding door 1, such that the door can no longer be entirely closed or damage occurs. The points where & collision can occur have been indicated in figure 3 with X.

Figure 4 shows a situation in which a maximum permitted transverse distance C is reached. Indeed, in case of an even greater spacing than C the lips 13, when closing the sliding door 1, will no longer hook behind or into each other but next to each other such that an opening is created between the sealing profiles along which water and wind would be able to penetrate.

The transverse distance is therefore restricted to a reach between B and C, for example, between 8 and 15 mm.

To make a greater reach possible without the aforementioned risks, the aforementioned guides are used according to the invention.

Figures 5 to 7 relate to a first type of guide 15. This first guide 15 is made up of, as shown schematically in a perspective view in figure 6, a first guide component 15a on the central mulLion 4a and a second guide component 15b on the other central mullion 4b that co-operates with the first guide component, whereby each of these guide components 15a and 15b is provided with a tooth 17a, respectively 17b, and a slot 38a, respectively 18b. The form and dimensions of the tooth 17 and slot 16 are such that in the closed situation of the sliding door 3. as shown in figure 5, the teeth 17 and slots 18 fit into each other in such a way that they keep the central mullions 4a and 4b at a transverse distance from each other which corresponds with the aforementioned nominal transverse distance A.

The guide components have a thickness D which preferably is approximately the same as the nominal transverse distance A.

The teeth 17a and 17b are provided with a wedge-shaped end with a bevelled guide surface 19a, respectively 19b, that defines a narrowing entrance to the slot 18 for the tooth 17b, respectively 17a, of the other guide component when closing the sliding door 1 the transverse distance between the central mullions 4a and 4b is greater than the nominal transverse distance A. This is the case, for example, in figure 7 with a transverse distance D corresponding with a maximum transverse distance E that is still permitted to allow the teeth 17a and 17b to grip with sufficient overlap F on each other to form a guide for the teeth 17 in the direction of the slots 18.

When, based on the extreme situation of figure 7, the central mullions 4a and 4b are slid further toward each other in the sliding direction X-X', the bevelled guide surfaces 19a and 19b slide over each other and thereby force the central mullions 4a and 4b toward each other until the nominal position of figure 5.

As can be clearly deducted from figure 7, the aforementioned maximum permitted transverse distance E, apart from the overlap F, is approximately double the thickness D of the guide components 15a and 15b and therefore approximately double the nominal transverse distance A. For a nominal transverse distance of, for example, 12 millimetres, the maximum permitted transverse distance, in the case of a first guide 15 according to the invention, can amount to, for example, 21 millimetres, compared to the maximum permitted transverse distance of 15 millimetres without this first guide 15.

The guide 15 is designed so that when the central mullions 4a and 4b move toward each other in the aforementioned way when closing the sliding door, the lips 13 of the sealing profiles 11 grip into each other correctly such as in the nominal situation of figure 2, without the lips 13 hitting each other.

One or both guide elements 15 can be fitted with a seal 20 which in the closed situation of figure 5 is pressed by the tooth 17 of the other guidance component 15 to form a seal between both guide components 15a and 15b.

On the outside the guide components 15 have a sunken part 21 that forms a seat for the draught strips 22 between the guide component in question 15 and the opposite central mullion 4.

The draught strips 22 extend according to the longitudinal direction Z-Z' of the mullions 4 and in the extension of the corresponding draught strips 23 on the sealing profiles 11.

According to a practical and easy to realise embodiment, the guide components 15a and 15b are made from essentially synthetic plate-shaped elements with a thickness D which is practically the same as the nominal transverse distance A, whereby the plate-shaped guide components 15a and 15b are attached with a side 26 on the sides facing each other 8a, respectively 8b, of the central mullions 4a, respectively 4b.

The slot 18 of an aforementioned guide element 15 of a central mullion 4 is formed because the plate-shaped element along the side facing the central mullion 4 in question has a sunken part 25 with a depth Fa, respectively Fb, which from a vertical side edge 26 of the plate-shaped element extends over a certain width Ga, respectively Gb, front the plate-shaped element. The tooth 17 of an aforementioned guide element 15 is formed by the remaining thickness Ha, respectively Hb, of the plate-shaped element on the level of the slot 18 formed by the sunken part 25. Preferably the thickness Ha and Kb of the tooth 17 and the depth Fa and Fb of the sunken part 25 are approximately to the amount of half the thickness D of the plate-shaped element _* The aforementioned wedge-shaped end of the teeth 17 is formed by the teeth 17 over their entire thickness Ha, respectively Hb, to form the bevelled guide surface 19.

The guide components 15a and 15b are positioned on the central mullions 4a and 4b in such a way that they are located at a sufficient distance I with the point of the teeth 17a and 17b from the inside edge 7 of the central mullion 4a or 4b in question to put in motion the guide between the guide components when closing the sliding door early enough to ensure the lips of the sealing profiles do not hit each other when closing the door.

The second guide 16 is fitted with a third guide component 16a on one of both central mullions, in this case on central mullion 4a. This third guide component 16a is provided with a wedge- shaped end with a bevelled guide surface 27a turned away from the central mullion 4a in question which descends in the direction of the inner edge 7a of the central mullion 4a and which when closing the sliding door 1 forms a guide for the other point X of the inner edge 7b of the other central mullion 4b as shown in figure 10, in order to push both central millions away from each other in the transversal direction Y-Y' when the transverse distance between the central mull.ions 4 when closing is smaller than the specified nominal transverse distance D and even smaller than the minimal required transverse distance B to avoid a sealing profile 11 hitting a central mullion as shown in figure 3.

When closing the sliding door, the second guide 16, in a first phase, will push away the central mullions 4a and 4b from each other until a transverse distance that is greater than the minimum transverse distance B before the situation of figure 3 is reached whereby the sealing profile lib comes past the inside edge 7a of the other central mullion 4a.

As is shown in figure .10, this means the central mullions 4a and 4b can come together very closely in the transversal direction Y-Y' up to a still safe distance K of, for example, 1 millimetre to put the guide safely in motion.

The minimum required transverse distance B of, for example, 8 millimetres without second guide 16 is strongly reduced thanks to the second guide 16 to a distance K of, for example, 1 millimetre.

The bevelled guide surface 27a of the third guide component 16a on the central mullion 4a is situated, seen from the sliding direction, between the guide surface 19a of the first guide component 15a on the central mullion 4a in question and the inside edge 7a of this central mullion 4a and at a distance J of this inside edge 7a.

This means the transverse distance between the central mullions 4a and 4b is first increased to the thickness of the third guide element 16a which preferably is the same as the thickness D of the guide elements 15a and 15b of the first guide and therefore approximately the same as the nominal transverse distance A, such that, after reaching this transverse distance D, the teeth 17 of the first guide hook into each other as in the nominal situation of figure 5. Preferably, opposite the third guide component 16a on the facing mullion 4b, a fourth guide component 16b is provided with a bevelled guide surface 27b that is complementary to the bevelled guide surface 27a of the third guide, component 16a.

According to a practical embodiment, the third and fourth guide component 16a and 16b are also made of synthetic material as a plate-shaped element with a thickness b, whereby the aforementioned bevelled guide surfaces 27a and 27b are formed by bevelling of a vertical edge 28a, respectively 28b, of the plate-shaped element over the entire thickness D of this element.

Each guide component 16a and 16b is provided with a sunken part 29 for the draught strips.

At least one of both bevelled guide surfaces 27a and/or 27b is fitted with a seal 30 which when the sliding door 1 is in a closed condition will be pressed between those two guide surfaces 27a and 27b to form a seal between both guide surfaces 27a and 27b.

According to a preferred aspect of the invention the guide components on one and the same central mullion 4 are made in one piece as shown in figure 11 wherein* for example, the first and third guide component 15a and Ida and the second and fourth guide component 15b and 16b in the vertical direction Y-Y' one above the other are connected with each other into one whole.

In this configuration the geometric surfaces of the bevelled guide surfaces 27a and 27b of the third and fourth guide component 16a and 16b run through the point of the wedge-shaped part of the first or second guide component ISa and 15b, such that the edges 26 and the edges 26 extend in each other's extension in the longitudinal direction Z- Z' of the mullions 4.

That benefits the compactness of the guides 15 and 16. Figure 12 shows how these composed guides are mounted, with omission of the front central mullion 4a for clarity' s sake. The composed parts are attached, for example, on the central mullions by means of screws 31 or the like.

The example shown in figure 12 shows a situation of a lift- slide door whereby first one wing 3 must be lifted in relation to the other wing to be able to unlock the sliding door 1. before the wings 3 can be slid apart to open the sliding door 1.

In this case in the locked situation of figure 12, a certain amount of vertical play L needs to be provided between the guide components in relation to each other to make a vertical shift possible between the guides when unlocking the lift-slide door as illustrated based on figure 13 wherein, in relation to figure 12, the left wing in relation to the right wing is pushed up as shown with the arrows M.

In the event of a sliding door without lift unlocking the play L is not necessary, but a small amount of play is desirable for safety to not let the guides hit each other when closing the sliding door 1.

The height of the guide components does not have to be big, for example, in the magnitude of. & couple of centimetres. It is clear that the guide components 15a, 15b of the first guide 13 and the guide components 16a and 16b of the second guide can change places in relation to each other. It is clear that the aforementioned dimensions are only provided as an indication by way of an example to indicate their proportions in relation to each other.

The first and second guides 15 and 16 are not necessary strieto senso and can also be used separately in a sliding door according to the invention, for example, in areas where the sag of the mullions is always expected to be outward or inward, whereby the first or the second guide 15 or 16 is then applied.

In areas wherein the sag can occur in both directions, applying a combination of first and second guides 15 and 16 is preferable. The present invention is by no means limited to the embodiments described as an example and shown in the figures, but a sliding door or sliding window according to the invention and guides thereby applied can be realised in all kinds of forms and dimensions, without departing from the scope of the invention.