DE9112157U1 - Curtain, especially for a non-rectangular (glass) surface - Google Patents

Abstract

The invention relates to a blind for a (glass) area, which is possibly to be shaded, in particular a non-rectangular area, with a hanging which in its shape corresponds essentially to the shape of the (glass) area, can be held on its first edge on a first holding means in the form of a stationary rail or the like, is fastened on a second edge lying essentially opposite the first edge to a second holding means in the form of a movable rail or the like which can be held detachably in position (at least) in the closed blind position, and which is guided on a first strand-shaped flexible guide means in the form of a cord, a tension wire, cable or the like, which runs between the first holding means and a stationary third rail or the like through the movable second holding means, as well as on a further strand-shaped flexible guide means, a first guide means, which is pretensioned by a (first) spring and can be held in a tensioned manner by the (first) spring in any position of the movable second holding means, running (with its strands) adjacently to the longitudinal edges of the hanging, and the second guide means, which is pretensioned by a second spring, running between the strands of the first guide means, and the strands of one guide means, which is in frictional engagement with the second holding means, intersecting in the region of the second holding means and being guided from one of its end sections to the other, from which they run in each case to the third rail or the like, the first guide means being in frictional engagement with the second holding means. <IMAGE>

Description

Alfred Stanley Brown, 24, Valley Road, Little Billing, Northampton, England

Curtain, especially for a non-rectangular (glass) surface

The invention relates to a curtain for a (glass) surface that may be shaded, in particular a non-rectangular surface, with a curtain that essentially corresponds in shape to the shape of the (glass) surface, which is to be held at its first edge to a first holding means in the form of a fixed rail or the like, is attached at a second edge that is essentially opposite the first edge to a second holding means in the form of a movable rail or the like, which is to be held releasably in position (at least) in the closed curtain position, and which is to be attached to a

518

Bremen:

Hollerallee 32, Poslf. 10 71 D-2800 Bremen

Telephone (04 21) 34 90 Fax (04 211 3 49 17 Telex 244 958 bopjt d

Berlin:

Uhlandstrasse 173/174 D-1000 Berlin

Telephone (0 30) 8 81 10 Fax (0 30) R Sl 39 Telex 1J3 6ö~, froirj d

Munich:

Widenmayerstrasse 4
D-8000 Munich 22

Telephone (0 89) 22 33 11
Fax (0 89)22 15 69
Telex 5?4 282 furbo d

Leipzig:

Philip-Rosenthal-Straße D (OJ-7010 Leipzig

Telephone (0037-41) 31 03 Fax (0037-41) 31 03

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first strand-shaped, flexible guide means in the form of a cord, a tension wire, rope or the like, which runs between the first holding means and a stationary third rail or the like through the movable second holding means, and on another strand-shaped, flexible guide means, whereby a first guide means, which is pre-tensioned by a (first) spring and is to be kept tensioned by the (first) spring in every position of the movable second holding means, (with its strands) adjacent to the longitudinal edges of the curtain, and that second guide means, which is pre-tensioned by a second spring, runs between the strands of the first guide means and the strands of a guide means, which is in frictional engagement with the second holding means, cross in the area of the second holding means and are guided from one end section to the other end section, from which they each run to the third rail or the like.

Such curtains with non-rectangular geometric shapes (which, in addition to the triangular and trapezoidal shapes already mentioned above, also include other polygons, circular segments, etc., whereby the above geometric terms are not to be understood in a strictly geometric sense, but in the broadest sense and, for example, in the case of a triangular or trapezoidal shape, should also include corresponding geometric shapes with non-linear side edges) are increasingly required, for example and in particular, for shading conservatories, greenhouses, etc., in order to be able to shade corresponding geometric sections of the glass surfaces if necessary.

It is necessary to guide the pleated curtain or curtain that is to be gathered in a known manner not only when it is moved from its closed position to the open position or vice versa, but also to keep it guided accordingly in the open and closed positions. This is generally done in a practical manner.

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moderately by means of strand-shaped guide means such as tension wires, cords or the like, which are guided (at least) conveniently adjacent to the side edges of the curtain through openings that have been expediently formed in advance in such a way that the strand-shaped guide means runs alternately in sections on the front and back of the curtain, so that the strands of the strand-shaped guide means, for example in the case of a triangular or trapezoidal curtain (corresponding to the area to be shaded), also essentially follow the corresponding shape, as is the case, for example, with the subject matter of DE-GM 12 709, i.e. with a curtain in which the guide means designed as tension wires form a corresponding trapezoid independently of the respective opening or closing state of the curtain, for example in the case of a trapezoidal curtain, and are thereby directly parallel to the side edges of the curtain.

In addition, the strands of the guide means, which run partly vertically and partly diagonally, extend through a movable middle rail, which is arranged between the upper rail and the lower rail and can be closer to the upper or lower rail depending on the desired opening or closing state, whereby in the case of the curtain known from DE-GM 89 12 709, in the case of a trapezoidal shape, there are (and must be) two further tension wires between the stationary upper rail and the stationary lower rail, which extend from the end sections of the upper rail to the longer, stationary lower rail. These further tension wires are necessary in the previously known curtain because its movable middle rail is made up of several parts (namely three parts), namely a middle section, the length of which is essentially the same as the length of the upper rail, as well as two adjacent

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Side sections, the total of which is equal to the difference in length between the lower and upper rails, so that the outer sections of the movable middle rail, which are each connected in an articulated manner to the middle section of the middle rail, must run to the middle section of the middle rail and horizontally and thus parallel to the lower and upper rails when the curtain is closed, because the outer sections of the movable middle rail, to which one edge of the curtain is attached, are each penetrated at their free end by a strand of the guide means formed from tension wires.

Quite apart from the fact that the curtain known from DE-GM 89 12 709 is extremely complex due to the multi-part design of the movable middle rail and the necessary joint connections, it is obviously extremely disadvantageous, especially in the case of a curtain made of pleated material, because the folds of the pleated material in the area of the triangular side sections can only maintain their intended course (parallel to the lower and upper rails) when opened and are deformed in the area of the joint connections as soon as the opening process begins, whereby this deformation process clearly increases continuously during the opening movement and the lowest folds of the curtain - depending on the trapezoidal shape - can under certain circumstances be deformed so much that permanent kinks occur in the curtain material, which are not only perceived as highly undesirable visually, but can also lead to an impairment of the functionality.

In addition, it is also considered disturbing in the curtain known from DE-GM 89 12 709 that the tension wires forming the guide means run diagonally to the first or second edge of the curtain when the curtain is open, and not in a direction in which (from

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the vast majority of the struts and other construction elements of a winter garden, greenhouse or similar run along this path (apart from any rafters that may be present).

From DE-GM 89 09 836, a guide device for a curtain, in particular a folding or slatted blind or a roller blind, is known which - as far as it concerns a curtain - is generically relevant. The curtain known from this publication does, however, avoid the disadvantages of the curtain according to DE-GM 89 12 709 described above, but it cannot yet optimally meet the requirements placed on a generic curtain.

In order to avoid the disadvantages described above with reference to the prior art according to DE-GM 89 12 709, in the curtain according to DE-GM 89 09 836, a box-shaped rail is provided at the fastening point of the lower edge of the curtain, in which a winding shaft is rotatably held on bearing pins. The winding shaft is hollow. A torsion spring is provided inside it, which is attached at one end to one end of the winding shaft and at the other end to a stationary bearing pin, whereby it should be noted at the same time that a similar bearing pin is also provided at the other end of the box-shaped rail, on which the winding shaft is mounted. The winding shaft is pre-tensioned in the winding direction by the torsion spring in order to keep the strand-shaped guide means (in the form of a rope) always taut.

However, it has been shown that such torsion springs are only suitable to a very limited extent for the intended use in question, and at least have significant handling disadvantages. Because of the unavoidable considerable friction, significant (large) forces are required for the beta

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The adjustment of this previously known curtain is necessary in order to achieve the desired effect of keeping the guide strands taut in every curtain position.

In addition, it has been found to be disadvantageous in the case of a curtain according to DE-GM 89 09 836 that those guide means were chosen as "brake cables" (i.e. as strand-shaped, flexible guide means) which run adjacent to the longitudinal edges of the curtain (essentially in the middle) between the outer guide means or guide means strands, since - as is readily apparent to the responsible expert - it is clearly not expedient, particularly in the case of relatively acute-angled, triangular curtains with regard to the desired (and required) braking effect, if the guide means strands that are more or less directly adjacent to the longitudinal symmetry line of the curtain perform the "braking task". In this context, it should be added that the two strands of the (middle) guide means forming the "brake cable" are connected at their end sections facing the (stationary) first holding means by a small tension spring, which is intended to hold the middle guide means in frictional engagement with the curtain or its through-openings.

It should also be noted that such brake cables, as presented in DE-GM 89 09 836 as (subjectively or supposedly) new, were already known at the time, for example from EP 0 195 483 Bl, i.e. a publication based on folding blinds of a different type with four rails, in which the strand-shaped guide means are in frictional engagement with the respective holding means, whereby in addition to the holding means of curtains of the same type, there is also another holding means in the folding blind according to EP 0 195 483 Bl and the curtain is arranged between this additional holding means and the second holding means.

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—*7—

In order to be able to hold the second holding means and the further (fourth) holding means (between which the curtain is arranged) in the respectively selected (intermediate) opening position (frictionally engaged), in the curtain (folding blind) known from EP 0 195 483 B1, the guide means designed as cords running between the second holding means and the further (fourth) holding means, which are stretched out between the second holding means and the further (fourth) holding means, are in frictional engagement with these two holding means.

The present invention is based on the task of improving the curtain according to DE-GM 89 09 836 while avoiding the above-mentioned and other disadvantages, in particular with regard to the arrangement of the guide means ("friction cables" or similar) that ensure the frictional holding of the second holding means (and thus ultimately the curtain). In addition, the type of spring force applied to the guide means strands should result in significantly lower resistance forces (caused by friction) when handling the curtain - with less effort - while at the same time aiming for a very simple (and also less conspicuous) design with a long service life.

The solution to this problem consists in that the first guide means is in frictional engagement with the second holding means.

Preferred embodiments of the present invention are described in the subclaims.

The invention is explained in more detail below using exemplary embodiments with reference to a drawing. It shows:

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Fig. 1 is a side view of a trapezoidal curtain according to the invention (without hangings) in the closed position;

Fig. 2 the curtain according to Fig. 1 (also without hangings) in the open position;

Fig. 3 the curtain according to Fig. 1 and 2 with the hanging in its open position according to Fig. 2;

Fig. 4 the curtain according to Figs. 1 to 3 with the hanging in its closed position according to Fig. 1;

Fig. 5 is a representation of another embodiment of a (trapezoidal) curtain with a side edge running at right angles to the upper and lower edge of the curtain and a side edge running at an angle to the upper and lower edge of the curtain (with curtain) in a representation according to Fig. 4; and

Fig. 6 the curtain according to Fig. 5 without hangings.

Fig. 1 to 4 show a curtain, designated as a whole by 1, for a trapezoidal (glass) surface (not shown) with a curtain 2 whose geometric shape essentially corresponds to the shape of the surface to be shaded, which has been omitted in Fig. 1 and 2 for the sake of clarity in order to be able to better illustrate the essential features of the curtain 1, and which can be seen in Fig. 3 in the open state of the curtain 1 or its curtain 2 as a kind of fold package, which in the open state according to Fig. 3 is created by the accordion-shaped folds of the pleated curtain material.

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rials together like a leporello.

The curtain 2 is held stationary at a first edge 3 by means of a rail ³¹ and is fastened to a second edge 4 opposite the first edge 3 on a movable rail 4', which can be releasably locked or held (frictionally) both in the closed curtain position (Fig. 1, 4) and in intermediate positions between the closed and open curtain positions.

Adjacent to its side edges (which run from the first edge 3), the curtain 2 is guided on a strand-shaped, flexible first guide means 5 in the manner of a tension wire, a cord, a rope or the like, which runs with two strands 6 and 7, which run through the curtain 2 in a sort of "wave-like" manner (see in particular Fig. 4) between the first holding means 3 ¹ and a third rail 15 and through the second holding means 4', which is also designed as a (movable) rail 4 ¹ , and is fixedly attached to the (third) rail 15 at the upper free ends (at 8) of the strands 5, 6.

The strands 6, 7 of the strand-shaped, flexible guide means 5 are each prestressed at their lower end section by an element 9 which generates a restoring force and which keeps the first guide means 5 tensioned in every position of the movable rail 4 ^1. In the present embodiment, the element 9 which generates the restoring force consists of two springs 9, 9, which are each assigned to a strand 6 or 7 of the first guide means 5.

The springs 9, 9 are tension springs, each of which is connected at one end to the associated, strand-shaped guide strand 6 or 7 and at its other end (adjacent to the first edge 3 of the curtain 2) to

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the fixed rail 3' or the surrounding area 10 are to be connected.

It can be seen that the first edge 3 of the curtain 2 is arranged or held in the stationary lower rail 3', and that the springs 9 are also arranged within this rail 3 ¹ (see Fig. 1, 2). The rail 3 ¹ has a through opening 11 for a strand 6 or 7 of the first guide means 5 on its side facing the first guide means 5, through which the guide means strand 6 or 7 coming from the movable rail 4' is guided and deflected (see Fig. 1, 2), each spring 9 having a deflection roller 12 on its end facing the respective guide means strand 6 or 7, around which the respective strand 6 or 7 is guided with its section leading to its fastening point 8 on the third rail 15.

It can be seen that the guide means strands 6 and 7 of the first guide means 5 are not guided "by the shortest route" through the movable rail 4' forming the second holding means, but that after entering the movable rail 4' at a through opening II ¹ they are each guided from the relevant end section of the rail 4' initially essentially parallel to the rail 4' to the other end section of the rail 4' and only there exit from the movable rail 4 ¹ from a through opening 11" (in each case after a corresponding deflection) in order to then reach the relevant fastening point 8 on the third rail 15 - at right angles to the holding means 3', 4' and 15.

The through openings 11' and 11" are designed in relation to the contour of the first guide means 5 in such a way that they are in frictional engagement with the through openings 11' and 11", so that an excellent frictional engagement is achieved.

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which is maintained even after a longer period of operation of the curtain 1, namely on the one hand/initially through the friction which arises due to the dimensioning of the through openings H ¹ , 11" in relation to the diameter of the strands 6, 7 of the first guide means 5, and on the other hand through the multiple deflection which arises (according to Eytelwein's equation) when wrapping around objects due to the wrap angle on the one hand and the friction coefficient on the other.

Even if, due to long-term use, a certain amount of abrasion occurs at the through openings 11', 11", so that the initially existing frictional connection is at least partially lost/worsened, the frictional connection resulting from this wrapping/redirection still remains, so that the curtain according to the invention remains functional even after a long period of operation and can be locked in all of the selected intermediate positions.

At this point it should be mentioned that the strand-shaped first guide means 5 can, according to one embodiment, be designed as one piece (and directly spring-loaded), whereby it can then be guided, for example, adjacent to the second edge 4 of the curtain 2 via a deflection roller 12 or the like to the other side and a further (second) spring arrangement can be fixed in place or this can also be dispensed with.

As already indicated above, it is not only expedient if the curtain 2 is arranged at its longer edge in its open position (see Fig. 2, 3), but also if this longer edge is arranged at the bottom .

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If the curtain 1 is to be closed from its open position, the movable rail 4 ¹ , to which the upper edge of the curtain 2 is attached, is pulled up from its lowered position according to the arrow 13. In the process, the tension springs 9, 9 relax while the strands 6, 7 are constantly tightened, which move from their initially angled, vertical arrangement in the open state (Fig. 2, 3) to their diagonal or slanted arrangement in the closed state (Fig. 1, 4).

It can be seen that the upper end sections of the strands 6, 7 run parallel to window beams, support struts, etc. when open, i.e. are arranged in a visually (aesthetically) highly satisfactory manner, while when closed they run directly adjacent to the side edges of the curtain and thus provide it with optimal guidance.

In the embodiment shown in Figs. 1 to 4, two further guide means strands 14, 14 are present, which form a second guide means. The two strands of the second guide means 14 always run essentially vertically, are arranged in the open state (Figs. 2, 3) immediately adjacent to the then vertical upper end sections of the strands 6, 7, so that an observer visually perceives essentially only two strands, and are connected to a (second) tension spring 16 at their end sections facing the first holding means ³¹ .

This basic concept also applies to the embodiment according to Figs. 5 and 6, which shows a curtain 1 with a hanging 2, the geometric design of which differs from the hanging 2 according to the embodiment according to Figs. 1 to 4, namely Figs. 5, 6 show a side view of a curtain 1 in the closed state, which, while adapting to the window or the like to be covered, has on its left side a perpendicular to the first holding means 3'.

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running side edge and has a slanted side edge on its right side. The basic construction here also corresponds to the construction described above with reference to Figs. 1 to 4 and differs (insignificantly) only in that the two stationary guide strands 14, 14 do not run essentially in the middle of the curtain 2, but are offset more towards the edge. Otherwise, the embodiment according to Figs. 5 and 6 is provided with the same reference numerals as the embodiment according to Figs. 1 to 4.

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B2491/I

List of reference symbols

1 Curtain 1 2 Curtains 2 3 first edge (of 2) 3' rail (fixed) 3 4 second edge (of 2) 4' rail (movable) 4 5 (first) management tool 5 6 Strand (of 5) 6 7 Strand (of 5) 7 8th Mounting points (of 5 or 6, 7) 8th 9 (first) spring 9 10 Surroundings (of 1) 10 11, 11',1I" passage opening 11 12 Deflection pulley 12 13 Arrow 13 14 Guide lines 14 15 (third) rail 15 16 (second) spring 16

Claims (12)

BOEHMERT & BOEHMERT, NORDEMANN and PARTNERS LAW FIRM To the German Patent Office Zweibrückenstrasse 8000 Munich PA DRING, KARL BOEHMERT (IW i9->ji
PA DIPL ING ALBERT BOEHMERT-, Bremen
&bull; Attorney WILHELM IH STAHLBERG, Bremen
PA DR-ING. WALTER HOORMANN-. Bremen
PA DIPL. PHYS DR, HEINZ GODDAR'. Munich
PA DR -ING ROLAND LIESEGANG·, Munich
Attorney WOLF-DIETER KUNTZE, Bremen
PA DIPL-PHYS. ROBERT MÜNZHUBER-, Munich PA DIPL-ING. EDMUND F. EITNER- <i»3J &igr;·*»)
LAWYER DR. LUDWIG KOUKER. Bremen
PA DR (CHEM) ANDREAS WINKLER- Bremen
PA DIPL ING THOMAS BUSCH, Leipzig
Attorney MICHAELA HUTH, Bremen
PA DIPL PHYS DR MARION TÖNHARDT. Munich RA PROF DR |UR WILHELM NORDEMASV' berlin RA DR. |UR KAI VINCK", berlin RA PROF DR. )UR PAUL W HERTIN", berlin Attorney Klaus Vom Brocke, Berlin PA Patent Attorney RA Attorney European Pattnt Ar.mey - Notary Your sign
Your ref. Your letter of New application (utility model) Our sign
Our ref. B2491/I Munich 24 September 1991 Alfred Stanley Brown, 24, Valley Road, Little Billing, Northampton, England Curtain, especially for a non-rectangular (glass) surface Expectations 1. Curtain for a (glass) surface that may be to be shaded, in particular a non-rectangular surface, with a hanging whose shape essentially corresponds to the shape of the (glass) surface, which is to be held at its first edge to a first holding means in the form of a fixed rail or the like, and is attached at a second edge essentially opposite the first edge to a second holding means in the form of a movable rail or the like, 518 Bremen: Hollerallee 32, PO Box 10 71 27 D-2800 Bremen 1 Telephone (04 21) 34 90 71 Fax (0421)3491768 Telex 244 958 bopat d Berlin: L'hlandstrasse 173/174 D-1000 Berlin Telephone (0 301 8 81 10 Fax (0 30) 8 81 39 Telex 1?'&idigr; 661 fnmn.,d Munich: Widenmayerstrasse 4 D-8000 Munich 22 Telephone (0 89) 22 33 &Pgr; Fax (0 891 22 15 69 &Tgr;&igr;-lex iJJ 282 forbo d Leipzig: Philip-Rosenthal-Strasse D (O1-7010 Leipzig Telephone (0037-41) 31 03 Fax (0037-41)3103 BOEHMERT & BOEHMERT, NORDEMANN and PARTNERS which is to be releasably held in position (at least) in the closed curtain position, and which is guided on a first strand-shaped, flexible guide means in the manner of a cord, a tension wire, rope or the like, which runs between the first holding means and a stationary third rail or the like through the movable second holding means, and on a further strand-shaped, flexible guide means, wherein a first guide means which is prestressed by a (first) spring and which is to be kept tensioned by the (first) spring in every position of the movable second holding means (with its strands) adjacent to the longitudinal edges of the curtain, and the second guide means which is prestressed by a second spring runs between the strands of the first guide means, and the strands of a guide means which is in frictional engagement with the second holding means cross in the region of the second holding means and are guided from one end section to the other end section, from which they each lead to the third rail or the like. characterized in that the first guide means (5 = 6, 7) is in frictional engagement with the second holding means (4 ¹ ). 2. Curtain according to claim 1, characterized in that the first spring (9) cooperating with the first guide means (5) is (at least) a tension spring which is connected at one end to a strand (6 or 7) of the first guide means (5) and is held stationary at its other end. 3. Curtain according to claim 1 or 2, characterized in that the first spring(s) (9) is (are) arranged within the stationary first holding means (3') holding the first edge (3) of the curtain (2). BOEHMERT & BOEHMERT, NORDEMANN and PARTNERS 4. Curtain according to claim 3, characterized in that the stationary second holding means (3 ¹ ) has on its side facing the first guide means (5) a through opening (11) for the strands of the first guide means (5), through which the guide means strands (6, 7) coming from the movable second holding means (4 ¹ ) are guided; and that the spring(s) (9) have (have) on their end(s) facing the guide means (5) a deflection roller (12) or the like, around which the strand-shaped guide means (5) is (are) guided with its section(s) leading to its fastening point (8). 5. Curtain according to one or more of the preceding claims, characterized in that the first guide means (5) is designed in one piece, with one strand of it being guided adjacent to the second strand (4) of the curtain (2) via at least one deflection roller or the like to the second strand, the free end of which is fixed in place. 6. Curtain according to one or more of claims 1 to 4, characterized in that the first guide means (5) is formed in (at least) two parts, each strand (6, 7) being acted upon by a separate spring (9, 9), and the other end of each strand (6 or 7) is fixed in place adjacent to the second edge (4) of the curtain (2). 7. Curtain according to one or more of the preceding claims, characterized in that the second spring (16) is a tension spring. 8. Curtain according to claim 7, characterized in that the second spring (16) is connected to the first holding means ( ³¹ ) BOEHMERT & BOEHMERT, NORDEMANN and PARTNERS reversed end portions of the strands of the second holding means (14). 9. Curtain according to claim 7 or 8, characterized in that the second spring (16) is arranged in/immediately adjacent to the first holding means (3 ¹ ); and that the section of the first holding means (3 ¹ ) facing the curtain (2) in the region of the strands (14, 14 ) of the second guide means (14) is designed such that the second spring (16) always keeps the second guide means (14) in frictional engagement with the curtain (2) or its through-openings. 10. Curtain according to one or more of the preceding claims, characterized in that the curtain (2) is arranged on its longer edge in its open position. 11. Curtain according to claim 10, characterized in that, in a substantially previously known arrangement of the curtain, the longer edge of the curtain (2) is arranged at the bottom. 12. Curtain according to one or more of the preceding claims, characterized in that the strands (6, 7) of the first guide means (5) each - running adjacent to a longitudinal edge of the curtain (2) - are guided from the first holding means (3 ¹ ) to the second holding means (4 ¹ ), there are guided under frictional engagement with the relevant through opening (11) essentially parallel to the second holding means (4 ¹ ) to its other end section, and there are guided under frictional engagement with the relevant through opening (11) to the third rail or the like.