FOLDING BLINDS FOR WINDOWS AND DOORS

Abstract: This invention relates to folding blinds for windows and doors, comprising a number of horizontally articulated slats connected to each other by means of hinged joints which, when the blind is raised, enable the slats to automatically fold like an accordion inside a box. Each slat features a pin terminating with a wheel, which is engaged by the teeth of two cams whose rotation allows the raising and lowering of the blind.

Description: Folding blinds for windows and doors. Technical field This patent application relates to folding blinds for windows and doors. Background art It is well known that the most commonly used blinds for windows and doors are roller blinds, composed of horizontally articulated slats, which may be manually wound around a horizontal shaft with a belt, or automatically, by means of an electric motor. The uppermost slat is integral with the shaft, which bears the entire weight of the blind, and this is the reason why it must be carried by strong supports, which are permanently fastened to the wall. One of the drawbacks of roller blinds in particular, and of blinds in general, is precisely the complexity of the twofold installation procedure: first of all, it is necessary to fasten the shaft supports , and then to fix the wooden box enclosing the space above the window/door housing the roller blind assembly. Another drawback of roller blinds is the large amount of space required to house the blind when it is fully raised, i.e. fully wound around the shaft; this space is generally larger than the thickness of the wall itself, and, therefore, it generally projects into the interior of the room, giving rise to a further two drawbacks: a purely aesthetic one and an essentially technical one, consisting m the fact that the greater the projection into the room, the further away from the window it will be necessary to hang the curtains, because the curtains generally cover the roller blind box, to hide it from view. The final result is the overall reduction of the room's floor area, compared to the case where it were possible to hang the curtains right next to the wall . Disclosure of invention This invention relates to window and door blinds which, when fully compacted, i.e. open, occupy less space than the current type of roller blinds and, in any case, less than the thickness of the wall in which they are contained, so that the box housing the blind is perfectly flush with the wall on the inside. This invention also relates to window and door blinds whereby all the components may be installed and supported inside the relative box, so as to make it easier and faster to install the blinds, since all that is required is to place the box inside the space above the wmdow/door and fasten it to the wall. These results have been achieved thanks to the invention's special structure, comprising a series of horizontally articulated slats which, when the blind is raised, automatically fold as they enter the box. Therefore, the width of the blind coincides with the width of one slat, since all the slats lie precisely one on top of the other, forming a pile of constant width, regardless of the number of slats composing the blind, whereas in the case of roller blinds, the greater the number of slats composing the blind, the larger the diameter of the spiral formed by the blind when open. The first or uppermost slat is fastened directly to the top of the box or, alternatively, when the blind is fully raised, it is in contact with the top of the box, while when it is fully lowered it goes to lie, by means of a pm, on a support above the pin guide, so as to reduce the overall height of the blind. The blind is raised by rotating two cams, which engage the heads of the pins on the middle of each slats and either drag them upwards or push them downwards. Alternatively, instead of the two cams, a chain-based or other similar system may be used, with the further advantage of requiring a smaller diameter than the cams and, therefore, enabling a further reduction of the box's width. Obviously, more than one pin may be applied at the ends of the slats, but the additional ones will not have rounded heads. The two lateral cams are driven manually, with a belt, or by a motor, through a set of cogged wheels connected the one to the other and to a driving shaft; the cogged wheels are housed inside an adequately sized metal box, capable of withstanding the effort required to raise and lower the blind ; the whole assembly is contained inside the box. Since the shaft is not required to support the weight of the blind, the relative supports may be fastened to the walls of the box, which, therefore, contains and supports both the blind and its driving mechanism. This means that the blind may be installed with a single operation, simply by introducing the box containing the blind into the space in the wall above the window/door and fastening it m place. Brief description of the drawings For a better understanding of the invention, the preferred embodiment will now be described in detail, with reference to the accompanying drawings, in which: Fig. 1 shows a perspective and schematic view of the blind, when it is fully raised inside the box; Figs . 2 , 3 and 4 show a couple of slats in the following positions, respectively: coplanar and detached ; coplanar and touching ; and superimposed, the one on top of the other, respectively; Fig. 5 shows the RH part of the box with some of the folded slats; Fig. 6 is fig. 5 shown from the left toward the right; Fig. 7 shows a cross-section of a slat near its end; Fig. 8 shows a cross-section of the lateral guides; Fig. 9 shows the slats with the hooks grouped together; Fig. 10 shows the slats in fig. 9, but separated; Fig. 11 gives a different view of the slats. Detailed description of the preferred embodiments With reference to the figures, the present blind comprises a series of slats (1) hinged the one to the others by means of connecting elements (2) with curved ends (2a) , which hook into the slots on the edges of each slat. In particular, on the upper edge of each slat (1) there is a semi-circular slot (la) , closed by a rounded rib (lb) , which engages the curved lower end of the connecting element (2) , while on the lower edge of each slat (1) there is a larger almost rectangular slot (lc) , which also features a rib (lb) similar to the one mentioned above, and which engages the curved upper end of the connecting element (2) . The slot (lc) is large enough to accomodate a part of the connecting element (2) , when two slanted and coplanar slats (1) come into contact (see fig. 3) ; for construction purposes, the slots la and lc may also be centred (see fig. 11) . It must be pointed out that the slots (la and lc) are decentralized and located at the opposite ends of each slat (1) , therefore the slats (1) must be alternately arranged so that the upper slot (lc) of one slat perfectly interfaces with the lower slot (la) of the slat (1) immediately above. At each end of the slats (a) there is a pm (3) with a rounded head (3a) or (3b) , enabling the cams (9) to engage the slats (1) when the blind is raised or lowered; outside the box (6) , the slats (1) assume a slanted position. Once inside the box (6) the slats (1) are folded and arranged one on top of the other, being forced into this position by the upward thrust of the cams (9) and the pin-heads (3a and 3b) running in the guides (8a and 8b) fixed to two box-shaped partitions (8) . With reference to fig. 7, the lateral guides (7) feature a specific housing (7a) in which the rounded heads (3a) and (3b) of the pins (3) slide. Inside the box (6) , besides the cams (9) and the driving shaft (5) , there are also specific guides (8a) , (8b) and (8c) fixed to the inside walls of the two box-shaped partitions (8) . The guides (7) continue inside the box (6) , on the RH and LH sides, above the cams (9) , where the guide (8a) splits into two arms (8b) and (8c) , at different heights, each arm facilitating the engagement of the wheels (3a) and (3b) at the ends of the pins (3) with the cams (9) , and each of the two arms of the guide being such as to oblige the slats to fold like an accordion; the pins (3) , integral with the slats placed at different heights (see fig. 5) , oblige the wheels (3a) , when the blind is lowered, to arrange themselves in the space between the guide and the preceding wheel (3b) , thus reducing the space occupied by the totality of the wheels when the blind is raised. On the inside wall of the box-shaped partition (8) , as previously mentioned, are fixed the guides (8a) , (8b) and (8c) for guiding the wheels (3a) at the ends of the pins (3) , while the slat (1) and cam (9) assembly remains outside of and precisely centred between the pair of box-shaped partitions (B) . The hollow space inside the box-shaped partitions (8) houses the cogwheels (10) , which are suitably protected and may act as reducers. The guides (8a) , (8b) and (Be) on the inside wall of the box-shaped partition (8) are so shaped and sized as to oblige the slats (1) to fold pair by pair, and to unfold in a likewise manner, to allow the pins (3) , when the blind is raised or lowered, to engage with the cams (9) at the same distance, thus achieving the uniform raising and lowering of the slats (1) . On the outside of one of the two box-shaped partitions (8) , precisely, on the wall opposite the guide (8a) , there is attached the motor for driving the blind or the pulley activated by the belt.

Claims: Claims (1) Folding blinds for windows and doors composed of a box (6) , a shaft (5) , two cams (9) and a set of slats (1) articulated by means of a connecting element (2) with curved ends (2a) which hook into specific slots (la and lc) on the edges of the slats, which also feature a pm (3) at each end terminating with a wheel (3a and 3b, respectively) , which pm engages the above mentioned cams (9) ; which cams are supported inside the box by two box-shaped partitions (8) ; on the RH and LH sides of the two box-shaped partitions (8) there is a guide (8a) , which divides into two arms (8b and 8c) , with different heights, each arm having a height corresponding to the pins (3a and 3b) and so shaped as to house the heads of the pins (3a and 3b) ; both the arms (8b and 8c) are so disposed as to oblige the slats to fold like an accordion when the blind is raised or unfold when it is lowered ; the slots (la and lc) are decentralized and located on the opposite parts of each slat (1) . (2) Folding blinds for windows and doors as claimed in Claim 1 wherein the slot (la) on the upper edge of each slat (1) is semicircular and closed by a rounded rib (lb) , while the slot (lc) on the lower edge of each slat (1) is almost rectangular shaped and is also closed by a rounded rib (lb) , similar to the one mentioned above ; the slot (lc) is large enough to accomodate a part of the connecting element (2) when two adjacent slats (1) take on a slanted position and come into contact the one with the other. (3) Folding blinds for windows and doors as claimed in the preceding claims wherein the pins (3) integral with the slats with different heights lead the rounded heads (3a) and (3b) at different heights so that when the blind is raised the pin head (3a) fits into the space between the guide and the preceding pm-head (3b) .

Inventors: CITTADINI ANTONIO, CITTADINI, ANTONIO
Applicants: CITTADINI ANTONIO, CITTADINI, ANTONIO
Application year: 1997
Main classification: E05D15
IPC codes: E05D15, E05F15, E06B9