DOOR TECHNICAL FIELD OF THE INVENTION The invention concerns a door, comprising a longitudinal, essentially horizontal guiding device, which extends over a door opening, and a door panel which is displaced on the guiding device STATE OF THE ART In many kinds of rooms it is suitable for many reasons to use sliding doors. A sliding door requires less space than a normal door that swings between its open and shut position. In certain respects it is also simpler to automate the opening and closing mechanism. Sliding doors are used to a large extent in hospitals and similar buildings.

Automatic sliding door systems are motor-driven today with several motors and/or gear devices. In order to prevent accidents while the door is closing, various safety systems are included. A sliding door system of this type is for this reason very expensive. Additionally, conscientious service and comprehensive maintenance are required. The high cost and comprehensive requirements on service constitute an essential disadvantage, especially in countries with weak economies.

There is thus a need for simpler and less expensive designs of sliding doors with lower requirements on service and maintenance.

THE INVENTION IN SUMMARY A purpose of the invention is to provide a sliding door that thanks to a simple design lacks the disadvantages indicated above. This purpose is achieved in that the invention incorporates the special features indicated in Patent Claim 1.

Further advantages and special features of the invention are evident in the following description, drawings, and dependent patent claims.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with the aid of ex- amples of embodiments with reference to attached drawings in which FIG 1 is a principal side view that shows a sliding door in the closed posi- tion according to a first embodiment of the invention with a first sys- tem for opening and closing the door, FIG 2 shows the door according to FIG 1 in a partially open position, FIG 3 shows an alternate system for opening and closing the door, and FIG 4 shows further an alternate system for opening and closing the door.

THE INVENTION The principal design of a door according to the invention can be seen in FIG 1. A guiding device 10 carries a door panel 11 and is approximately twice as wide as door panel 11. In this embodiment, door panel 11 hangs on strut 12 with rollers 13 in guiding device 10. Rollers 13 are well journaled and roll easily in guiding device 10. Door panel 11 covers a door opening 14, but can leave a gap of approx. 10 mm at the floor.

Guiding device 10 is not completely horizontal, as opposed to conven- tional guiding devices for similar purposes, but rather it is designed in a V- shape with two shanks 15,16 located in an obtuse angle towards each other. Guiding device 10 is held in position by a lever boss 17 where the shanks meet. Shanks 15,16 can also be bent slightly upwards so that guid- ing device 10 assumes a U-shape.

In the configuration shown in FIG 1, a first left-hand shank 15 as- sumes a horizontal position, while a second right-hand shank 16 is angled

upward by some degrees. In this configuration door panel 11 hangs stably on guide device 10 and covers door opening 14. By swinging guiding device 10 somewhat in the direction of arrow A, the stabile position is left and door panel 11 begins to roll to the right through the force of gravity, since first shank 15 constitutes a downward-sloping track for rollers 13. After rolling some distance along guiding device 10 door panel 11 will pass the position shown in FIG 2.

When guiding device 10 swings from the horizontal position, door panel 11 will, as was indicated above, try to swing to the same tilted position as that of the one shank of guiding device 10. In order to decrease this swinging or tipping movement of door panel 11, a door stop 28 that is fas- tened to the wall or floor can be provided at the bottom by the side of the door panel. Door stop 28 also functions to set door panel 11 in motion by forcing the door panel to move sideways when guiding device 10 is lifted. A corresponding door stop can be provided on the opposite side of door panel 11 for the same function when the movement of the door panel is in the op- posite direction.

In order to effect the required slant for guiding device 10, different de- vices can be provided. In the embodiment according to FIG 1, two line sys- tems of the same kind are provided. A first line 18 is attached in a first point of attachment 19 somewhat above second shank 16 and then runs vertically down towards and 180° around a first idler pulley 20. First line 18 then runs over a second idler pulley 21, where the line turns 90° to the left and goes farther over a third idler pulley 22, from which first line 18 runs vertically downwards and ends at first handle 23.

A second line 18'is fastened in a corresponding way to a second point of attachment 19'and runs around its first idler pulley 20', its second idler pulley 21', and its third idler pulley 22'and ends after a vertical portion with a second handle 23'. Lines 18,18'are guided by control device 24 in the final vertical portion, so that they do not slip off their respective third idler pulleys 22,22'when the lines are maneuvered with handles 23,23'.

In order to open the sliding door in the embodiment according to FIG 1, it is sufficient to pull on second handle 23', whereby first idler pulley 20'is lifted upwards as a block and lifts first shank 15 on guiding device 10. Rollers 13 are thus set in motion and the whole door panel 11 is displaced to the right.

In order to limit the motion of rollers 13 on the guiding device, stops 29 are positioned at the ends of guiding device 10. Stops 29 can also be con- stituted by the end walls of guiding device 10. In a stabile position with the door open or closed, a roller 13 bears on stop 29. The second roller is lo- cated in a position near the midpoint of guiding organ 10, from which second shank 16 extends with a certain upward slope. The door is thus put in such a position that a swinging motion of guiding device 10 according to the above, or a considerable horizontal force to the right in FIG 1, is required to move door panel 11 from door opening 14.

In the position shown in FIG 1, left-hand shank 15 rests on a support plate 30 fastened to the wall, and a corresponding support plate is positioned at right-hand shank 16. Support plates 30 limit the movement of guiding de- vice 10, so that the shanks cannot move below a horizontal plane.

FIG 2 shows how the situation is when door panel 11 is moved on its rollers 13 a bit to the right, so that a part of door opening 14 is free. During part of the movement to the right, door panel 11 will be somewhat displaced from the horizontal position. A track in the floor can be used in order to take up a corner of door panel 11. The track can be omitted if door panel 11 hangs somewhat above the floor in its resting position.

An alternative to the system using lines according to FIG 1 is shown in FIG 3. In this alternate embodiment a double-action pneumatic cylinder 25 is fastened to a wall on one end and on guiding device 10 on the other, so that the end on guiding device 10 can be pressed down or lifted up. The desired swinging movement can also be effected in this way. Pneumatic cylinder 25 is activated by a control device in the form of a keypad or similar placed at a suitable location.

FfG 3 also shows schematically how guiding device 10 is angled. An- gle a, which defines the one shank's deviation from a horizontal position, can be on the order of magnitude of 1-5°. Angle a can be adjusted to the weight and width of the door and to how quickly the door should open and close.

With a door panel 11 having a weight of 20 kg and a roller bearing with a di- ameter of 65 mm for rollers 13 a suitable acceleration and movement of the door panel is obtained at an angle position of a = 2°. This angle position cor- responds to an elevation of door panel 11 of 26 mm at the corner of the door panel.

FIG 4 shows schematically a further alternative to a line system ac- cording to FIG 1. Two single-action cylinders 26,27 are provided in a position opposite each other and flexibly attached in guiding device 10 at a certain radial distance from lever boss 17. Single-action cylinders 26,27 are fixed in relation to the walls and door opening 14. By pressurizing one of the single- action cylinders 26,27 a torque is created that tilts guiding device 10 in the desired way. Single-action cylinders 26,27 can be replaced by a double- action cylinder. The required lifting arm action against guiding device 10 can also be effected in another way and with a different attachment of cylinders 26,27 on guiding device 10. Guiding device 10 in the embodiment shown in F1G 4 is of U-shape with somewhat rounded-off shanks 15,16. By devising shanks 15,16 in U-shape, as described above, it is possible to effect a brak- ing motion in door panel 11 before it reaches its end point at stopping device 29 and a quicker setting into motion of the door panel from the end position.

It is also possible to position two doors of the kind described above adjacent to each other in order to cover a wider door opening or if two nar- rower door panels 11 are desired. The two door panels in such an embodi- ment are suitably mounted so that they are actuated simultaneously and both door panels are displaced away from each other when the doors are opened and towards each other when the doors are closed. The door panels function as door stops for each other in the way described above.

It is also possible to position the guiding devices in the floor so that the door panels rest on rollers or wheels that run in the guiding device. A control device should in such a case be positioned above the door opening. The guiding devices can be actuated with a foot lever having a lifting action or similar.