US 3141497 A
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F. GRIESSER VENETIAN BLIND Filed Aug. 31, 1959 INVENTOR FRITZ GRIESJER United States Patent 3,141,497 VENETIAN BLIND Fritz Griesser, Aadorf, Thurgau, Switzerland, assignor to Griesser A.G., Aadori', Thurgau, Switzerland Filed Aug. 31, 1959, Ser. No. 837,035 Claims priority, application Switzerland Sept. 9, H58 4 Claims. (Cl. 160-170) The present invention relates to a Venetian blind having its lowermost or end slat engaged by pull members adapted to be wound and unwound around a winding shaft and further having supporting members for pivoting the slides and supporting the latter and adapted to be coupled to the winding shaft by frictional engagement.
The pull members and the supporting members of heretofore known Venetian blinds of this type are formed by relatively broad stiff tapes made for example from textile material or from steel. While it is known to form the pull members as thin cords or wire cables which, when wound on the winding shaft, are arranged in close windings on this shaft, by longitudinal displacement thereof, it was conventional to use for the supporting members tapes which, owing to their width, did impair the esthetical appearance and in addition thereto required a particular supporting surface on the winding shaft not used by the pull members. A particular drawback of such supporting tapes appears when the Venetian blinds are arranged between the panes of a double pane window. With the blind gathered the supporting tapes engaging the rims of the slats form a bellow outwardly projecting harmonica-like beyond the edges of the slats and bearing against the window panes requiring much place so that this bellow must be taken into consideration when the distance separating the window panes and the widths of the slats respectively is determined.
It is a prime object of the present invention to avoid these drawbacks.
To this end the Venetian blind according to the present invention is characterized by the fact that not only the pull members extending upwardly to the winding shaft through openings in the slats but also the supporting members engaging the edges of the slats and lying in form of a loop on the winding shaft at the same place as the pull members are made of ropes or cables.
The thin supporting ropes or cables do not form stiff and cumbersome bellows. The rope loops projecting beyond the slat edges when the blind is gathered are flexible and may be placed between the blind and the window panes even if this space is very small. Also in the esthetical respect the exclusive use of ropes or cables as compared with the heretofore used tapes must be considered as a progress. Practice has moreover shown that the ropes which at least partly are made of synthetic fibres do not suflier any wear.
Other features and advantages of the invention will become apparent from the ensuing description of a preferred embodiment thereof given by way of example only with reference to the accompanying drawings, in which:
FIGURE 1 is a vertical section through the housing of a Venetian blind according to the invention containing the winding shaft and the gearing;
FIGURE 2 is a plan view of FIGURE 1 with the blind gathered;
FIGURE 3 is a plan view similar to that of FIGURE 2 with the blind lowered;
FIGURE 4 is a view from the left-hand side in FIG- URE 3;
FIGURE 5 is a section taken along the line V-V in FIGURE 1 with the blind gathered, and
FIGURE 6 is a section similar to that of FIGURE 5 with the blind lowered.
Referring to the drawing reference numeral 1 desig- 3,141,497 Patented July 21, 1964 nates a casing of U-shaped section, laterally closed by end walls 2, 3. An intermediate wall 4 separates in the casing 1 the gear chamber from a chamber containing a winding shaft 5. A gearing 6 of known type comprises a drive tab 7 having a square boring adapted to receive the end of a not represented driving crank. The outlet shaft of the gearing 6 is provided with a square extension 8 projecting through a corresponding opening in the intermediate wall 4. This extension 8 carries a supporting block 9 which is longitudinally displaceable on it and has secured to it the end of the tubular winding shaft 5. The other end of the winding shaft 5 is rivetted to a supporting block 10 having a threaded boring by means of which it is screwed onto a threaded spindle 11 secured to the end wall 2. The outer front sides of the supporting blocks 9 and 10 are each provided with an abutment 12 adapted to cooperate with an abutment 13 at the opposite walls 2 and 4 respectively.
In the represented embodiment a pull member and a supporting member engage the winding shaft at two longitudinally spaced points thereof. The pull members 14 secured with their one end to the winding shaft 5 are ropes consisting at least partly of synthetical threads made for example from terylene or the like. Of course it could also be made of wire cords or cables. They extend from the winding shaft 5 each through an opening 15 in the base of the casing and through corresponding central openings of the slats 16 and are anchored in a way known per se and for this reason not represented with their lower end at the lowermost or end slat. The supporting members 17 arranged in the zone of the pull member 14 also consist of wire cables or of ropes comprising synthetical threads. Each supporting rope 17 is provided in known manner with double webs 17a superposed in spaced relationship and receiving the slides 16 between them. The supporting rope extends through openings 18 in the casing base and surrounds the winding shaft 5. The openings 18 are arranged on both sides and in one line with respect to the opening 15 for the pull member or rope 14.
At the left hand side in FIGURES 1 and 2 the blind is shown partly gathered. The winding shaft 5 is in a middle position and the pull members 14 are partly wound on the winding shaft in adjacent windings while the supporting ropes 17 bear in frictional engagement on the winding shaft. In order to lower the blind, the winding shaft 5 is rotated in direction of arrow 11 in FIGURE 1 by means of the not represented crank handle and of the gearing 6. Thereby the pull ropes 14 are unwound from the winding shaft 5 and the latter is axially displaced in direction of arrow b in FIGURE 1 on the spindle 11 and the square extension 8. The arrangement is such that when the blind is fully lowered (FIG- URE 3), the abutment 12 at block 10 bears against the abutment 13 provided at the end wall 2 so as to prevent further rotation of the winding shaft. Thereby it is to be noted that during rotation of the winding shaft 5 in the sense of lowering the blind, the supporting ropes 17 strongly bear with their upper loop against the winding shaft. The latter owing to frictional engagement en trains in rotation the supporting ropes 17 so that the slats; 16 are tilted into the closed position shown in FIGURE 4. Upon further rotation of the winding shaft the loop of, the supporting rope slides on the shaft.
In order to displace the slats 16 into another position the winding shaft 5 is rotated in the direction opposite to arrow at in FIGURE 1. As the loops of the support-. ing ropes 17 always bear strongly on the winding shaft 5,. they are entrained by frictional engagement. Thus, the; slats 16 may be tilted in horizontal position (FIGURE 6). or into any desired position between the two closed posi 'tions.
9 The closed position opposite to that shown in FIGURE 4 of the slats 17 is indicated in dot-and-dash lines in FIGURE 6.
In order to raise the blind the winding shaft 5 is rotated in the direction opposite to that of arrow a. By the progressing axial displacement of the winding shaft 5 towards its end position at the intermediate wall 4 the pull ropes 14 are wound on the winding shaft in adjacent windings. Simultaneously with the gathering of the slats 16 which thereby forcibly take the horizontal position shown in FIGURE 5, outwardly projecting loops are formed by the portions of the supporting ropes between the slats 16. Obviously, such outwardly projecting loops are very flexible and not cumbersome in contradistinction to the loops of the heretofore tapes. An undesirable pressure is not exerted by such rope loops against the adjacent window panes between which the blind is mounted. The arrangement moreover is such that when the blind is fully gathered the winding shaft 5 has attained its end position on the gear side whereby the abutment 12 at the block 9 abuts against the abutment 13 at the intermediate wall 4 as is shown at the right in FIGURES 1 and 2. In this position the pull members 14 release the supporting ropes 17 so that when the blind is fully gathered the loops of the supporting ropes 17 are lifted from the winding shaft 5 (FIGURES 1 and 2).
The abutments 12, 13 provided at both sides prevent undesired further rotation of the winding shaft beyond its end positions corresponding to the full lowering and gathering respectively of the blind which otherwise could lead to undue tensile stresses on the ropes 14.
1. A Venetian blind comprising a winding shaft, a plurality of slats, pull members in the form of a single cord engaging the lowermost of said slats and extending upwardly to the winding shaft through openings in the slats, said pull members being adapted to be wound and unwound around said winding shaft, supporting members supporting the slats and adapted to be coupled by frictional engagement with the winding shaft for pivoting the slats, said supporting members engaging the edges of the slats and lying in form of a loop on the Winding shaft at the same portion thereof as the pull members, the respective supporting members lying in a plane with the respective pull members, said plane being perpendicular to the winding shaft, said pull members and said supporting members being of a rope-like material.
2. A Venetian blind as claimed in claim 1, in which the winding shaft is longitudinally displaceable so that upon rotation of the shaft in the sense of at raising of the blind the pull members are wound around the winding shaft in adjacent windings, the loops of the supporting members being spaced above the winding shaft when the blind is in the fully raised position.
3. A Venetian blind as claimed in claim 2, in which both front ends of the winding shaft are provided with abutments adapted to cooperate in the end positions of the shaft with stationary abutments in order to limit the axial displacement of said shaft.
4. A Venetian blind as claimed in claim 3, in which the winding shaft is a tube supported by means of supporting blocks with its one end on a stationary threaded spindle and with its other end on a square extension of the outlet shaft of the gearing.
References Cited in the file of this patent UNITED STATES PATENTS 1,978,152 Ward Oct. 23, 1934 2,152,116 Wade et al. Mar. 28, 1939 2,374,591 Dunn Apr. 24, 1945 2,405,255 Horton Aug. 6, 1946 2,520,629 Esposito Aug. 24, 1950 2,598,887 Burns June 3, 1952 FOREIGN PATENTS 33,551 Germany Nov. 27, 1885