US3857433A

US3857433A - Foldable shutter

Info

Publication number: US3857433A
Application number: US00342866A
Authority: US
Inventors: W Gatzi
Original assignee: MATALLBAU AG ZURICH
Current assignee: MATALLBAU AG ZURICH
Priority date: 1972-03-23
Filing date: 1973-03-19
Publication date: 1974-12-31
Anticipated expiration: 1991-12-31
Also published as: DE2312661A1; DE2312661C3; FR2177098B1; IT983580B; ATA236773A; DE2312661B2; AT342847B; NL7303469A; FR2177098A1; CH550932A

Abstract

A foldable shutter or Venetian blind of the type wherein the slats or lamellae hingedly connected with one another have operatively associated with both of their ends a respective guide bolt cooperating with an associated guide surface of a guide rail arrangement having a respective control groove extending substantially parallel to the associated guide surface. Each end portion of the shutter, at which operatively engages a drawband for the foldable shutter, is guided in the guide rail arrangement. Each end of each of the slats carries a stop or latch pin which is arranged in substantially parallelly offset relationship with respect to the associated guide bolt and cooperates with an associated bearing surface or support provided at the guide rail arrangement. The spacing of each bearing surface or support from the associated guide surface of the guide rail arrangement is smaller than the spacing between the guide bolts and the stop pins and that the control groove extends between the associated guide surface and the bearing surfaces or supports.

Description

nited States Patent [191 [451 Dec. 31, 1974 FOLDABLE SHUTTER [75] Inventor: Walter Giitzi, Zurich, Switzerland [73] Assignee: Matallbau AG Zurich, Zurich, Switzerland 22 Filed: Mar. 19,1973

211 App]. No.: 342,866

[30] Foreign Application Priority Data UNITED STATES PATENTS 3,473,597 10/1969 Chevaux 160/172 3,520,346 7/1970 Green 160/172 3,651,852 3/1972 Neri 160/172 3,744,544 7/1973 Wellensiek 160/ 172 Primary Exam in erPeter M. Caun Attorney, Agent, or FirmWerner W. Kleeman [5 7 ABSTRACT A foldable shutter or Venetian blind of the type wherein the slats or lamellae hingedly connected with one another have operatively associated with both of their ends a respective guide bolt cooperating with an associated guide surface of a guide rail arrangement having a respective control groove extending substantially parallel to the associated guide surface. Each end portion of the shutter, at which operatively engages a drawband for the foldable shutter, is guided in the guide rail arrangement. Each end of each of the slats carries a stop or latch pin which is arranged in substantially parallelly offset relationship with respect to the associated guide bolt and cooperates with an associated bearing surface or support provided at the guide rail arrangement. The spacing of each bearing surface or support from the associated guide surface of the guide rail arrangement is smaller than the spacing between the guide bolts and the stop pins and that the control groove extends between the associated guide surface and the bearing surfaces or supports.

20 Claims, 19 Drawing Figures 0U TSID E AREA INS/DE PAIEmEnnEwW 3.857.433

'* sum 20; 5;

Pmminnmi V 1857.433-

- sum w 5 FOLDABLE SHUTTER BACKGROUND OF THE INVENTION The present invention relates to a new and improved construction of foldable shutter or Venetian blind of the type wherein its slats or lamallae which are hingedly interconnected have associated with both of their respective ends or end faces a respective guide bolt cooperating with an associated guide surface of a guide rail arrangement having a respective control groove for each shutter end portion extending parallel to the associated guide surface, and at which guide rail arrangement there is guided each end portion of the shutter and with which shutter there engages at least one drawband.

According to a state-of-the-art construction of foldable shutter or Venetian blind of this general type the slats in their extended position assume a completely extended positional orientation, i.e., the plane containing the slats coincides with the plane of the shutter. In vertical direction each second hinge-like joint formed between neighboring slats is only guided in the guide rail arrangement by means of the ends of hinge rods protruding past the end faces of the slats. This construction which is relatively simple cannot however be employed for shutters where, in the closed condition thereof, the planes of the slats should maintain an angle with respect to the plane of the shutter. Since only each second hinge arrangement is guided it is possible for there to occur an irregular folding of the slats; in the extreme case two neighboring slats can bear upon one another in the completely folded together condition, whereas two other neighboring slats of the same shutter can be found to be located in an extended, that is to say, unfolded condition.

According to another prior art foldable shutter or Venetian-type blind guiding of the slats in vertical direction occurs between two rails which are in operable engagement by means of a respective recess with each end of a slat. In order to limit the folding angle which the slats can assume relative to one another in the folded-up condition and to prevent binding or clamping of the slats at the rails in such condition, slats which are similarly directed are connected by wires with one another at their lengthwise edges confronting the inner area at which the shutter is located. This construction of foldable shutter or Venetian blind is associated with the drawback that the slats, which incidentally are only connected with one another by bands, in the folded-up state, are movable in a pendulum or oscillatory fashion in accordance with the amount of play present between the rail arrangement and the recesses. Hence, even in the presence of relatively inconsequential wind loads flapping noises or other annoying sounds exist and, in may instances, prohibit the use of this type foldable shutter.

SUMMARY OF THE INVENTION Hence, it is a primary object of the present invention to provide a new and improved construction of foldable shutter which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.

It is another and more specific object of the present invention to provide a new and improved construction of foldable shutter wherein the slats, in the folded-up condition of the blind or shutter, are positioned in a predetermined orientation by means of a rigid guidingand support system.

Yet a further significant object of the present invention relates to a new and improved construction of foldable shutter or Venetian-type blind which is relatively simple in construction and design, economical to manufacture, extremely reliable in operation, not readily subject to breakdown or malfunction, and provides for relatively noiseless use and positive fixation of the shutter slats in desired position.

Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the invention contemplates that each slat end carries a stop or latch pin which is arranged in parallelly offset relationship with respect to its associated guide bolt and which cooperates with an associated bearing surface or support provided at the guide rail arrangement, and the spacing of the supports from the associated guide surface of the guide rail arrangement is smaller than the spacing between the guide bolts and stop pins and that the control groove extends between the associated guide surface and the associated bearing surfaces or supports.

Owing to the use of guide rails or a guide rail arrangement and pins cooperating therewith, and which pins in turn are directly attached to the slats of the shutter, the shutter can be beneficially operated in a trouble-free manner, in other words can be unfolded without clam ping or binding, and each individual slat fold can be fixedly retained in its desired position. Consequently, with the shutter unfolded there prevails, optically considered, a uniform image, which, in the case where there are arranged a larger number of such foldable shutters at a facade or structure, is of decisive importance as concerns its aesthetic appearance. Moreover, due to the positioning and mounting of the individual shutter folds, that is to say, the slats forming the folds of the shutter, there is practically suppressed any development of noise by virtue of the use of the foldable shutter which might be brought about by external influences, in particular wind surges or loads, for instance.

Due to the use of the proposed guide rail arrangement, particularly owing to the special configuration of the legs of each U-shaped constructed guide groove thereof and which legs face away from the supporting arrangement, there is realized the advantageous result that the ends of the slats are completely covered. Consequently, there is extensively completely suppressed both passage of light as well as communication of light through the shutter.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIG. 1 is a cross-sectional view of an embodiment of foldable shutter of Venetian blind in its lowered position, and taken substantially along the line I-l of FIG.

FIG. 2 is a cross-sectional view of the foldable shutter in its folded condition;

FIG. 3 is a cross-sectional view of the foldable shutter, viewed in a position during opening thereof;

FIG. 4 is a cross-sectional view through the guide rail of the foldable shutter or Venetian blind, taken substantially along the line IVIV of FIG. ll;

FIG. 4a is a further embodiment of the guide rail depicted in FIG. 4 for the foldable shutter, shown in cross-sectional view and taken substantially along the line IVa-lVa of FIG. lb;

FIG. 4b is a cross-sectional view through the guide rail depicted in FIG. 4a, taken substantially along the line IVb-IVb thereof;

FIG. 4c is an enlarged illustration of the support or bearing depicted in FIGS. 4a and 4b, shown in crosssectional view, taken substantially along the line IV- c-IVc of FIG. 4d,

FIG. 4d is a plan view of the bearing or support depicted in FIG. 40, again shown in cross-section, and taken substantially along the line lVdIVd of FIG. 4a;

FIG. 42 illustrates a modified shutter arrangement;

FIG. 5 is a cross-sectional view, on an enlarged scale, through the foldable shutter or Venetian blind of FIG.

FIG. 6 is a front view of the foldable shutter of FIG.

FIG. '7 illustrates a further embodiment of the foldable slats for the foldable shutter;

FIG. 8 illustrates details of cover plate means for covering openings in the foldable slats;

FIG. 9 is a cross-sectional view through the cover plate means depicted in FIG. 8, taken substantially along the line IX-IX thereof;

FIG. 10 is a cross-sectional view through a wind-up roller arrangement;

FIGS. I1 and I2 illustrate respective cross-sectional views in different operating positions of the arrangement of FIG. 10, taken substantially along the line XI-XI thereof; and

FIGS. 13 and 14 illustrate respective cross-sectional views of the arrangement depicted in FIG. 10, again in different operating positions, and taken substantially along the line XIII-XIII thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now the drawings, in FIG. 1. reference numeral 10 generally designates a foldable shutter or Venetian-type blind construction which comprises a foldable shutter 12 having substantially horizontally arranged slats, a shutter drive 14 and a guide rail arrangement 16 for the shutter 12. The foldable shutter 12, as the same has been illustrated on an enlarged scale in FIG. 5, possesses so-called screening slats 18 which face towards the side where the rays of the sun impinge, these screening slats 18 being arranged in spaced relationship from one another and in substantial parallelism. The expression slats I8 directed towards the sun ray impinging side," or equivalent terminology, is intended to convey the concept that the edges of the slats l8 confronting the inside area or room with which the shutter 12 is employed are located at a greater height or elevation than those edges facing towards the outside. The screening slats 18 arranged in spaced relationship from one another are interconnected by means of pairs of guides or guide links 20, and specifically such that the lower edge, that is to say, the edge of a screening slat 18 facing the outside is connected with an edge of the next successive lower situated screening slat, and which last-mentioned edge faces the inside area. The free spaces between the individual screening slats 18 are each covered by a respective regulating or control slat 22, the significance of which will be discussed more fully hereinafter.

The lengthwise extending edges of the screening slats 18 facing towards the outside are hingedly connected with the guides 20 by hinge or pivot bolts 24. Similarly the lengthwise extending edges of the screening slats 18 facing towards the inside area are hingedly connected or articulated with the guides 20 by the hinge or pivot bolts 26. At the lower edge of the foldable shutter or Venetian blind 12 there is arranged a so-called collecting rail 28 having a catch or receiving trough 30. The

significance of the collecting rail 28 and its receiving trough 30 will become readily apparent from the discussion given hereinafter. Furthermore, at the lowermost regulating or control slat 22, at the side confronting the inside area, there is attached in any convenient way a closing weight or ballast 32, the purpose of which will also be discussed hereinafter.

At this point it is briefly indicated that the various exemplary embodiments of foldable shutter given herein by way of illustration are of essentially symmetrical construction with respect to the vertical extending centerline thereof, so that as a matter of convenience in the disclosure and in the illustration of the drawings there have generally only been shown and discussed the arrangement of the components along or at one side of the lengthwise centerline of the essentially centrally symmetrical shutter.

The foldable shutter 12 is both guided and fixedly retained at both ends in the guide rail arrangement or guide rail means 16, as best seen by referring to FIG. 6. For this purpose each of the individual guide rails 16a of the guide rail means 116, as the same has been depicted in cross-section and enlarged view in FIG. 4, is provided with two separate channels or grooves, that is to say, a guide groove or channel 3 3 with the guide sur face 31 and a further guiding groove or channel 36, also referred to herein as a control channel or groove 36. The

grooves

34 and 36 are arranged at lateral spacing from one another. Furthermore, merging with the control or guiding groove 36, and considered in the lengthwise direction of the guide rail arrangement 16, are a number of bracket-like bearing surfaces 38 arranged in spaced relationship from one another. The guide rail arrangement 16 is here disposed such that the bearing surfaces or supports 38 are directed towards the inside area. If for some reason, for instance because of space requirements, it is necessary to carry out a change in the rail arrangement, then it would be possible to also have the bearing surfaces or supports 38 directed, for instance, towards the outside.

Now for the purpose of effectively guiding the foldable shutter or Venetian blind 12 in the guide rail arrangement 16 there are provided, on the one hand, the hinges or pivot joints 24 equipped with guide bolts 40, which can extend past the ends of the individual slats and thus extend into the region of the associated guide groove or channel 34 and, on the other hand, the hinges or pivot pins 26 are provided with the latch or stop pins 44 which, in turn, cooperate with the supports or bearing surfaces 38 of the associated guide rail 16a of the guide rail means or arrangement 16.-

At both ends of the collecting rail 28 there is arranged a respective pin 42 which extends into the control channel or further guide groove or channel 36. The function of these pins 42 will be considered hereinafter. A leg 35 of each guide groove or channel 34 is constructed such that it extends past the lateral ends of the slats 18 in the direction of the opening which is to be covered by the shutter proper, as best seen by referring to FIG. 4. Due to this construction of the legs 35 there is realized an optimum lightand visual closure between the guide rail arrangement 16 and the foldable shutter 12.

Now in FIGS. 4a, 4b, 4c and 4d there is shown both a further exemplary embodiment of the guide rail arrangement 16 depicted in FIG. 4 as well as a further variant of the bearing surface or support 38 depicted in FIG. 4. Now in these Figures there is designated by reference character 120 a guide rail arrangement or guide rail means which cooperates with a guide system 122. The foldable slats 124 of the shutter are operatively connected with this guide system 122.

The guide rail arrangement 120 possesses at each end of the slats a guide groove or channel 126 and a control channel or further guide groove or channel 128. At the guide rail arrangement 120 there is located a still further guide groove or channel 130 which faces away from the aforementioned channels or

grooves

126 and 128. The end portions 132 of the legs 132' forming this U-shaped guide groove 130 are flexed or bent towards one another in such a way that between these confronting ends there is formed a slot-shaped opening 134 which is open throughout the entire length of the associated guide groove 130. Secured to the leg 136 of the control or guiding groove 128 is a toothed rail or rack 138 which cooperates with stop or latch pins 140 arranged at the borders or flanges 123 of the associated foldable slats 124. Each pin 140 possesses an extension 142 at which there is rotatably mounted a respective guide or guide link 144 and a connection arm 145. Each of the guide 144 as well as the connection arm 145 is provided at its free end with a respective further pin 146. This pin 146 furthermore carries at its axial end guide rollers 148 which cooperate with guide surfaces 131 of the guide channel or groove 130.

Both the rack 138 as well as also the periphery of the stop of locking pin 140 are provided with sawtooth-like constructed locking or engaging

teeth

152 and 154 respectively. The teeth 152 of the rack 138 as well as those, namely the teeth 154, of the stop or locking pin 140 are constructed such that they can mesh with one another.

In FIG. 6 the centerline symmetrically constructed foldable shutter or Venetian blind arrangement is shown in front view. In this Figure there can be especially recognized the screening slats 18, the guides 20, the guide bolts 40 for the screening slats l8 and the pins 42 of the collecting rail 28. Furthermore, in this showing of FIG. 6 there is also depicted the regulating or control band 46 and a drawband 48 for the foldable shutter 10, the significance of which will be discussed shortly hereinafter, and in the exemplary embodiment given by way of illustration such bands are located at each end of the shutter.

Now in FIGS. 1, 5 and 6 the foldable shutter 10 has been depicted in its lowered or let-down position. The screening slats 18 and the regulating or control slats 22 cooperate with one another in such a way that there is interrupted any passage of light from the outside into the inside area. By actuating, in other words by specifically drawing-up or pulling upon a regulating or control band 46 the regulating slats 22, which are connected via hinge connection elements 47 with the regulating band 46 (FIGS. 1, 2, 3, 5) are rotated about the hinge or pivot pins 24, so that, depending upon the degree of opening, they allow for a greater or lesser passage of light and air through the shutter 12.

In order to actuate the foldable shutter 12, in the case under consideration for gathering-up this foldable shutter, the shutter drive 14 is rotated in clockwise direction. In so doing the regulating bands 46 are displaced in downward direction whereby the regulating slats 22 completely close. Only then is each drawband 48, which is mounted in the associated lateral guide groove 36 of the guide rail means 16, entrained by the shutter drive 14. Each drawband 48 is connected with its associated pin 42 which, in turn, are fixedly secured to the collecting rail 28. By actuating the shutter drive 14 the collecting rail 28 is drawnup towards the shutter drive 14. During this operation the pins 42 prevent any lateral deviation of the collecting rail 28 out of the plane of the foldable shutter 12. As soon as the collecting rail 28 has been raised towards the drive 14, then, the lowermost screening slat 18 of the foldable shutter 12 together with the stop or locking pins 44 is displaced out of the support or bearing surface 38. This screening slat 18 is now displaced into a position parallel to the lowermost guide link or connection web 20 of the foldable shutter 12 and finally bears at the inclined portion of the collecting rail 28. The catch or receiving groove 30 of the collecting rail 28 prevents any lateral displacement of the gathered-up screening slats 18. The collecting rail 28 is drawnup for such length of time until all of the screening slats 18 as well as all of the regulating or control slats 22 are gathered-up beneath the drive 14 and collected together in the form of a package of slats, as best seen by referring to FIG. 2.

During lowering of the foldable shutter 12, and as best seen by referring to FIG. 3, the drive 14 will be rotated in the counterclockwise direction. In so doing, there is lowered each drawband 48 together with the therewith connected collecting rail 28. At the same time there is lowered the entire package or set of screening slats 18 as well as the regulating slats 22. The uppermost screening slat 18 is connected by means of its lengthwise edge confronting the inside area, via a suspension band 50, with the housing of the drive 14. As soon as the package composed of the screening slats 18 and the regulating slats 22 lowers, then the edge of the uppermost screening slat 18 confronting the inner area is held backby the suspension band 50. The length of the suspension band 50 is selected such that the hinge 26 and together therewith the stop or looking pins 40 comes to bear exactly at the uppermost support or bearing surfaces 38 of the guide rail means 16. This operation is assisted by the hinge or pivot joint 24 of the uppermost screening slat 18 in that the guide bolts 40 commonly mounted at the hinge 24, during lowering movement in the associated guide groove 34, draws the associated stop or locking pin 44 against the outer wall of the associated control or guiding groove or channel 36. Since the spacing between two supports or bearing surfaces 38, in the lengthwise direction of the guide rail means 16, is chosen such that the width x of the screening slats 18 and the length y of the guides 20 (see FIG. 1) positively direct the stop or locking pins 44 into the associated bearing surface or supports 38, and wherein the guide surfaces 31 assist this operation, there is realized an automatic separation of the foldable shutter 12 as soon as the collecting rail 28 begins to descend. In so doing both the individual screening slats 18 as well as also the individual guides or guide links are fixedly retained between the bearing surfaces or supports 38 and the corresponding guide surfaces 31 of the guide grooves 34.

In order to ensure for a better opening and closing of the regulating slats 22 there is provided the aforementioned weight or ballast 32 at the lowermost regulating slat. It is of course also possible, instead of using a weight 32, to provide a non-illustrated tension spring which, for instance, connects the lowermost regulating slat 22 with the collecting rail 28.

It is furthermore also possible to arrange the foldable slat elements of the illustrated foldable shutter or Venetian blind 12 vertically instead of horizontally. However, in this instance it is to be observed that the closing operation, instead of being carried out by the inherent weight of the shutter would be assisted by additional mechanical auxiliary means.

Now in FIG. 7 there is illustrated in cross-sectional view a particularly advantageous constructional embodiment of foldable shutter 12. The basic idea of the configuration for the different components of the foldable shutter 12 resides in the fact that the individual elements in the folded condition can be stacked within one another within the smallest possible space. For this purpose it is necessary to maintain the leg length a both of the screening slats 18 as well as also the guides 20 and the regulating slats 22 to be the same length. Also for this purpose it is necessary to maintain the leg length b of these three components or elements of the shutter 12 so as to be the same. According to a further constructional feature there is to be ensured that the angle a formed by the legs a and b for each of these three

elements

18, 20, 22 is of the same magnitude.

Now in the arrangement of FIGS. 8 and 9 there is designated by reference character 52 a cover plate. In the event that with the shutter 12 of the development of this invention it is desired to especially close wide openings then it is necessary to support the individual elements of the shutter 12, that is to say, the screening slats 18 as well as the regulating slats 22, at one-half of their width with additional drawbands or support cords 58, so as to prevent any undesired throughbending of the individual components or elements. However, when employing these measures it is necessary to provide the screening slats 18 as well as the regulating slats 22 with the openings 60 so that bands or cords 58 which are necessary for supporting these slats can be drawn through the components of the shutter. In order to maintain as small as possible the passage of light at the location of these required openings 60, which generally are constructed to be of slot-shaped configuration, it is possible to provide for instance the cover plates 52 which can be inserted into such openings 60. Each cover plate 52 will be understood to consist of, by way of example, two

disks

54 and 56 arranged to both sides of, for instance, an associated screening slat 18 or regulating slat 22. These disks or

plates

54, 56 cover an opening 60 which is provided for the purpose of permitting throughpassage of a cord 58 or the like for instance. The two disks or

plates

54 and 56 of the cover plate 52 are connected with one another by an intermediate web 62. This web 62 is designed such that, viewed in the lengthwise direction of the individual slats, it fits practically without play into the opening 60, perpendicular to the lengthwise direction of the slats however can laterally displace, so that in this way there can be accommodated displacement of the cord 58 with respect to the screening slats 18.. The

disks

54 and 56 as well as the web 62 possess an opening 53 intended to permit the throughpassage or threading therethrough of the cord 58.

It is of course conceivable to construct the proposed.

foldable shutter of Venetian blind 12 without any regulating slats 22. Such construction of shutter would then be particularly suitable for a room or space area which only requires protection against the sun, yet does not require a complete darkening of the room or a complete shutting-off of the outside view. Furthermore, it is also conceivable, instead of employing the guides 20 and the regulating slats 22, to provide a second screening slat which renders it possible to screen an area com pletely against the entry of light. This additional screening slat can be advantageously provided with openings which render possible optimum lightand air throughpassage, without however rendering it possible to have free visual access from the outside into the inner area. Such openings are advantageously arranged at the leg a (see FIG. 7) of the screening slat which is employed instead of the guide 20.

In the exemplary embodiments of foldable shutters described in conjunction with FIGS. 1 to 7 (excluding FIGS. 4a and 4b) the shield or armour construction formed by the slats forms a unit, that is to say, the indivdual slats are connected in a force-locking or positive fashion with one another. In order to retain such slat shield in desired position it is mounted in the guide rail means 16 of the invention. In order that this shield forms a unit the slats 18 subjected to the rays of the sun are either connected with one another by guides 20 or with such guides 20 by means of further slats which in cross-section coincide with these guides. This is necessary in order that the individual slats, when they are gathered-up or when the slat shield is lowered or letdown, mutually displace in the desired position.

It is of course also conceivable to arrange this forcelocking system which is enclosed in the slat shield defined by the shutter proper 12, externally thereof in the guide rail arrangement 16 or respectively. This possibility has been depicted in FIGS. 4a and 4b.

During operation of this exemplary embodiment the slats 124 cooperate as follows with the guide system 122 in the guide rail means or arrangement 128: during drawing-up or lowering of the slats 124 the drawband 48 together with the collecting rail 28, (as such has also been depicted in FIG. 4 by position 48) will be correspondingly moved in the control or further guiding groove 128. Upon actuating the drawband 48 the collecting rail 28 will be correspondingly raised or lowered. At the collecting rail 28 there is secured the last screening slat 124. The screening slat 124 (FIG. 4a) is connected via the stop or locking pins as well as its extensions 142 with the guide system 122 and its guides 144 and connection arms 1415. If now the collecting rail 28 is raised then, via the lowermost slat 124, the guides 144 and the connecting arms 145 are displaced against one another, as same has been described in conjunction with the disclosure of FIGS. 1, 2 and 3 in corresponding manner as the slats 18 and the guides 20.

It is also possible to connect the slats 124 via the stop or locking pins 140 rigidly with the connecting arms 145 which extend approximately in the plane like the slats 124. In this way the guide bolts 40 arranged at the flange or border 123 of the slats 124, and which guide bolts cooperate with a guide surface 127 of the guide trough or channel 126, can be omitted. With this con struction the slats 124 will participate in each positional change of the connecting arm 145 which is rigidly connected therewith.

The constructional embodiment depicted in FIGS. 4c and 4d of the bearing surface or support 138 possesses the advantage, in contrast to the bearing surface or support 38 depicted in FIGS. 1, 2, 3 and 4, that manufacturing inaccuracies in the folding system can be better compensated.

Furthermore, it is of course also possible, instead of the arrangement, depicted in FIGS. 4, 4b, 4c and 4d, of bearing surfaces or supports 38, 138 which are located between the individual slat borders or

flanges

26, 125, to arrange therebetween spacer springs or bands 156, as same has been depicted in FIG. 4e. These spacer springs or bands 156, in this case, assume the function of the supports or bearing

surfaces

38, 138 and retain the individual folds defined by the slats of the slat shield at approximately the same spacing with respect to one another.

New in FIG. there is shown in sectional view the shutter drive 14, as the same can be advantageously constructed for actuating the foldable shutter or Venetian blind 12.

Now in FIG. 10 reference numeral 64 designates a shaft which cooperates with a transmission or gearing drive 66. The transmission 66 can be manually driven or by means of a suitable motor viaa drive shaft 68. A hub 70 is seated upon the shaft 64, this hub 70 being rigidly connected for rotation with the shaft 64 by means of a wedge or key 72 or equivalent. Upon the hub 70 there are arranged adjacent one another a first drum 74 and a second drum 76. Now at the hub 70 as well as at the

drums

74 and 76 there are arranged keyways or

grooves

78, 80 and 82 which correspond to one another. Now in the keyway 78 of the hub 70 there is mounted a key or wedge 83, over which, at the region of the drum 74, there is arranged a second key or wedge 84. The key 84 is provided with a nose-shaped raised portion 86, the significance of which will be considered hereinafter. Beneath the key 83 there are provided at the hub 70 as well as at the region of the drum 74 as well as also at the region of the drum 76

openings

87 and 89 respectively, in each of which there is mounted a respective spring 88 and 90. At the flank or end face of the drum 76 which confronts the drum 74 there is arranged a bolt 92, the function of which will also be discussed shortly. The drum 74 is provided for the purpose of receiving a drawband 48 or the like; the drum 76 in turn is intended for winding-up a regulating band 46.

Upon actuation of the drive 14 the shaft 64 is placed into appropriate rotational movement by operating the drive shaft 68 and also through the action of the transmission 66. As a result, the hub 70 keyed with the shaft 64 is entrained. Now if the foldable shutter or Venetian blind 12 is opened, that is, the drawbands 48 wound onto the drum 74, then these drawbands 48 press the key 84 into the keyway 82, the key 84 then bearing upon the key 83, and such then disappears into the keyway 78. Consequently, the drum 74 is placed in rigid rotational connection with the hub 70, whereas the drum 76 is loosely located upon the hub 70, and therefore, does not follow the rotational movement of the hub 70.

If the shutter 12, as depicted in FIG. 1, is completely closed, that is to say, until such time as the collecting rail 28 bears for instance against the windowsill, then the drawbands 48 at drum 74 relax in such a way that the pressure generated by the springs 88 and 90 displaces the key 84 via the key 83 out of the keyway and thus releases the drum 74 from its rigid rotational connection with the hub in a manner that it no longer follows the movement of the hub 70. Simultaneous with the raising of the key or wedge 83 the drum 76, how ever, is brought into rigid rotational connection with the hub 70, so that now the drum 76 participates in the movement of the shaft 64. By means of such drum 76 it is possible to now actuate, as required, the regulating slats. However, in order to allow this actuation to be carried out it is necessary that the drawbands 48 are arranged to run in the opposite direction with respect to the regulating bands 46 upon the

drums

74 and 76 respectively. By virtue of these measures it is possible to further rotate the shaft 64, after the shutter 12 has been lowered in the same direction, to thereby bring about a raising of the regulating slats 22.

In FIGS. 11 to 14 this operation has been depicted in greater detail. The arrows designated in FIGS. 11 and 13 by

reference characters

94 and 96 respectively, designate the direction of rotation of the shaft 64 wihch is required in order to lower the shutter 12. The drawbands 48 wound upon the drum 74 press the keys or

wedges

84 and 83 into the keyways or

wedge grooves

78, 82 in such a way that between the hub 70 and the drum 74 there prevails a rigid rotational connection. As soon as however the drawbands 48 are completely wound-off the drum 74 the springs 88 and displace the

keys

83 and 84 out of the

keyways

78, 82 in such a manner that the connection location or interface between two

keys

83, 84 coincides with the contact location between the hub 70 and the drum 74. As a result, the rigid rotational connection between the hub 70 and the drum 74 is released. The drum 74 therefore no longer participates in the rotational movement of the shaft 64. During pushing of the

keys

83 and 84 respectively out of the keys arrangement there is simultaneously however established a rigid rotational connection, by means of the key 83, between the hub 70 and the drum 76, as such has been illustrated in FIGS. 12 and 14. Through further rotation of the shaft 64 there is now realized the effect that the regulating bands 46 are wound onto the drum 76, rendering possible raising of the regulating slats 22.

In order to be able to draw-up or raise the shutter 12 it is necessary to rotate the shaft 64 in the direction of the

arrows

98 and 100 of FIGS. 11 and 13 respectively. Consequently, the regulating bands 46 are again wound-off the drum 76, with the result that the regulating slats 22 are closed. During rotation of the drum 76 there is simultaneously entrained the bolt 92 secured to the drum, as best seen by referring to FIG. 12, qnd which during its rotation impinges against the nose 86 of the delatched key or wedge 84 and entrains such together with the drum 74, so that the key 84 now again comes to lie exactly over the keyway 78 of the hub. It is also necessary to adjust the bolt 92 and the nose 86 ill of the key 84 with respect to one another in such a manner that the key 34 will be entrained by the nose 86 and the bolt 92 just shortly before the regulating slats are completely closed. As soon as the drum 74. is entrained by the bolt 92; the drawbands 48 are again entrained by the drum 74 and stressed in such a way that the wedge 84, which is now located exactly over the keyway 78, is pressed into such keyway, and therefore there is again established a direct driving connection between the hub 70 and the drum 74. During pressing of the key 84 into the keyway 78 the key 83 is also pressed into the keyway 78, with the result that the rigid rotational connection between the hub 70 and the drum 76 is again released.

While there is shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims. Accordingly,

1. A foldable shutter comprising slats, means for hingedly connecting the slats with one another, said slats having operatively associated with each of their respective opposed ends a respective guide bolt, guide rail means having guide surface means with which cooperate said guide bolts, said guide rail means further incorporating control channel means extending substantially parallel to the associated guide surface means of the guide rail means and in which there is guided an associated end portion of the shutter, a drawband for the shutter, support means provided for said guide rail means, each end of the slats carrying a stop pin arranged in substantially parallelly offset relationship with respect to the associated guide bolt and cooperating with said support means provided for the guide rail means, the spacing of the support means from the guide surface means of the guide rail means being smaller than the spacing between the guide bolts and the stop pins and wherein the control channel means extends between the guide surface means and the support means.

2. The shutter as defined in claim 1, wherein the drawband is arranged in a control channel means of the guide rail means and is connected with a pin member of the end portion of the shutter, said pin member engaging with the guide rail means.

3. The shutter as defined in claim 2, wherein a drawband is arranged at each end of the shutter.

4. The shutter as defined in claim 1, wherein the guide surface means constitutes a part of a substantially U-shaped channel and wherein a surface of the U- shaped channel located opposite the guide surface means comprises a cover leg member.

5. The shutter as defined in claim 4, wherein the cover leg member covers the neighboring end portion of the slats.

6. The shutter as defined in claim 1, wherein the control channel means has a leg portion and said support means are arranged at a substantially uniformly spaced distance from one another at said leg portion of the control channel means.

7. The shutter as defined in claim 6, wherein the spacing between neighboring support means of the guide rail means substantially corresponds to the spacing of the slat folds of the shutter defined by the slats.

8. The shutter as defined in claim 6, wherein the support means are formed by brackets.

9. The shutter as defined in claim 6, wherein the support means are formed by toothed rails.

10. The shutter as defined in claim 6, wherein the support means include spacer bands which connect the stop pins of neighboring slats with one another.

11. The shutter as defined in claim 1, wherein similarly situated neighboring slats are interconnected with one another by a plurality of guides defining said connecting means.

12. The shutter as defined in claim 11, wherein the guides have mutually offset means which directly hingedly connect neighboring slats with one another.

13. The shutter as defined in claim ll, wherein each end of the slats possesses a connection arm at the free end of which there engages one of the guides.

14. The shutter as defined in claim 12, wherein each connection arm is arranged at an end of the associated slat and pivotably connected therewith.

15. The shutter as defined in claim 13, wherein the connection arm is arranged approximately in the plane of the associated slat and rigidly connected therewith.

16. The shutter as defined in claim 13, wherein the hinge joint between a connecting arm and the neighboring guide carries an associated guide bolt.

17. The shutter as defined in claim 11, wherein between similarly situated neighboring slats there are provided lightand air passage openings and these openings are covered by pivotable regulating slats.

18. The shutter as defined in claim 17, wherein the regulating slats possess free lengthwise edges connected with one another by regulating bands.

19. The shutter as defined in claim 18, further including a common drive for the regulating bands and each drawband.

20. The shutter as defined in claim 19, wherein the drive comprises a rotatable shaft equipped with drum means for receiving each drawband well as drum means for receiving each regulating band, and wherein each drawband and regulating band is disposed to operate in opposed relationship with regard to one another at the drum means and means for alternately rigidly drivingly connecting such bands with the rotational shaft of the drive.

Claims

4. The shutter as defined in claim 1, wherein the guide surface means constitutes a part of a substantially U-shaped channel and wherein a surface of the U-shaped channel located opposite the guide surface means comprises a cover leg member.

13. The shutter as defined in claim 11, wherein each end of the slats possesses a connection arm at the free end of which there engages one of the guides.

17. The shutter as defined in claim 11, wherein between similarly situated neighboring slats there are provided light-and air passage openings and these openings are covered by pivotable regulating slats.