Carrier for blinds with swivelling vertical strips

Abstract

 A supporting carrier for blinds comprising swivelling vertical strips or panels. A hooking element (6) comprises a hook-shaped lower part and an upper shank (16) inserted into a hole (30) of a supporting sprocket wheel (5), connected to a worm screw (8) sliding along a horizontal control rod (9) for all the carriers (2) of the blind. The hooking element (6) and the sprocket wheel (5) are provided with frictional surfaces (18, 33) reciprocally engagaging with a certain amount of friction; stop means (25,26) on the carrier (2) cooperate with a lateral tooth (24) on the hooking element (6) to automatically define two end angular positions of the hooking elements (6) for a parallel arranging of all the vertical strips of the blind.

Description

[0001] This invention concerns a carrier for blinds with swivelling vertical strips,in which each strip or panel of textile or similar material, is suspended from a carrier running along horizontal rails, by means of a hooking element.

[0002] There are known carriers for supporting blinds with vertical strips, in which the hooking el= ement of the strip is connected to a sprocket wheel which engages with a driving worm screw sliding along a control rod, by means of which it is possible to simultaneously turn all the panels of the blind in the desired direction. The hooking element is either fixed directly to the sprocket wheel, or it is connected by means of a supplementary frictional device.

[0003] With the first type of carrier, it is impos= sible to change the initial position of the hooking element once the blind has been as= sembled, in order to arrange all the vertical strips on a parallel line with one another, consequently this operation must be carried out in a rather approximate way when assembling the blind. With the second type of carrier,the angular position of the hooking element can be changed even after the blind has been assembled, thanks to the use of a frictional device provid ed between the hooking element and the sprocket wheel; however, fitting the frictional device, in this second type of carrier proves to be lab orious and expensive.

[0004] The aim of this invention is to overcome these problems by providing a running carrier for sup porting the swivelling vertical strips of blinds, in which the hooking element.of the strips can be rotated on the axis of the sprocket wheel even after assembling, in order to adjust the initial angular position of the strips themselves, and in which the frictional device forms an integ ral part of the hooking element and of the sprocket wheel itself.

[0005] The advantages offered by this invention consist in greater simplicity in constructing and assembl ing the carrier, together with a subsequent reduct ion in costs, due to the fact that the sprocket wheel and the hooking element, together with their frictional portions, can be moulded or shaped in one piece, in plastic or other material having a certain amount of elasticity.

[0006] An embodiment of the invention is described in detail hereunder, with reference to the annexed drawings, in which :

Fig. 1 shows a cross section of a carrier;

fig. 2 shows a partially cutaway view, along the line 2-2 of Fig. 1:

Fig. 3 shows a side view of the hooking element;

Fig. 4 shows a top view of the hooking element of Fig. 3;

Fig. 5 shows a lengthwise cross-section of the single sprocket wheel;

Fig. 6 shows a detail of the carrier of Fig.1

[0007] The figures show part of a vertical strip or panel-type blind, comprising a rail 1, suitable for fixing the ceiling or to the wall, within which there are carriers 2, only one of which is shown in the figures, provided with wheels for running along the rail itself. The carrier 2 comprises a frame defining a housing 4 for a sprocket-wheel 5 and a hooking element 6 partially protruding downwards from an aperture 7 (Fig. 6) in the lower wall of the housing 4 of the carrier; a vertical strip or panel of textile material (not shown) hangs in the usual way from the hooking element 6, to form part of the swivelling-strip blind.

[0008] The sprocket wheel 5 engages with a worm screw 8 which slides lengthwise along a control rod 9, arranged laterally, and passing through aligned apertures 10 on both side walls of the carrier 2. Rotation of the worm screw 8, by means of the control rod 9, is achieved by providing the rod 9 with lengthwise slots 11 in which teeth, or appropiate ribbings in the abovementioned worm screw; engage and slide.

[0009] Figures 3 to 5 show, in greater detail, a pre= ferred embodiment of the hooking element 6 and sprocket wheel 5, with the frictional portions which engage reciprocally with a pre-established degree of friction. In particular the hooking element 6 comprises a lower hook-shaped part 12 which continues with a neck portion 13 defined by lower shoulders 14 and by a circular upper shoulder 15, by means of which the sprocket wheel 5 - hooking element 6 assembly is rotary supported in the hole 7 at the bottom of the housing 4 in the carrier.

[0010] The hooking element.6 is provided with a pivot= ing shank 16, to the side of, and parallel to which, there are frictional elements 17; these elements 17 are flexibly yielding and present an outer cylindrical surface 18, for engaging, with a certain amount of friction, with the matching inner cylindrical surface 33 of the frictional portion of the sprocket wheel 5, hereunder described with reference to figure 5. The frictional elements 17 are disposed at a short distance from the shank 16, present a circular segment cross-section and extend only along part of the length of the shank itself, as shown.

[0011] The shank 16 of the hooking element presents, on its upper half, a lengthwise wedge-shaped split 19 and.lateral protrusions 20 defining stop shoulders for preventing the shank 16 from axially slipping out after assembling into the sprocket wheel 5; sloping surfaces 21 on the up= per end of the shank 16 facilitate the insertion of the upper part of the shank 16 when fitting _f into the axial hole of the sprocket wheel, as shown in figure 1. Likewise,the neck portion 13 of the hooking element 6 presents a length= wise slit 22 and sloped surfaces 23 joining to the hook-shaped part 12, in order to permit the abovementioned neck portion to yield flex= ibly during its assembling into the hole 7 of the carrier.

[0012] Lastly, 24 indicates a lateral tooth situated on the neck portion 13 which engages with stop surfaces 25 and 26 at the opposite ends of a semi-circular protrusion 27 on the lower wall of the housing 4, as shown in figure 1 and 6. The tooth 24 and the stop surface 25 and 26 cooperate in defining two opposite end posit= ions, rotated by 180° for the hooking element 6 and the strip or panel of the blind.

[0013] Figure 5 shows the structural shape of the sprocket wheel 5. This sprocket wheel 5 which, likely the hooking element 6, can be molded from plastic material with a certain amount of flexibility, presents an upper part with external toothing 28 designed to engage with the elical toothing of the worm screw 8, and a lower or frictional part 29. The sprocket wheel 5 presents,more= over, an axial hole 30 on its upper part,design= ed to receive the pivoting shank 16 of the hook= ing element 6, the hole 30 joining to an.upper circular cavity 31 and to a lower cylindrical cavity 32 respectively, of larger diamater. The lower cavity32 defines a frictional surface 33 designed to come mutually into contact with the frictional portion of the hooking element 6 defined by the element 17.

[0014] The carrier is assembled and functions as follows: the shank 16 of each hooking element 6 is insert= ed into the hole 30 of the respective sprocket wheel 5, and pushed in with a certain amount of force until lateral protrusions 20 on the upper end of the shank, which in the hole is a flexibly compressed, snap into the recess 31 of the sprocket wheel; in this condition, the shank 16 of the hooking element 6 is axially held by the opposing 15 and 20.

[0015] Moreover, the hooking element 6 may be rotated with respect to the sprocket wheel 5, by over= coming a certain amount of frction due to the reciprocal engaging of the frictional portions 17 and 29 of the aforementioned hooking element and sprocket wheel respectively. The hook-shaped part 12 is then inserted into the hole 7 of the carrier, using a certain amount of ef= fort due to the radial compression of the neck portion 13, until such neck portion snaps into the aforementioned hole 7; the hooking element 6 and sprocket wheel 5 assembly is thus assembled on the carrier 2. The control rod is then insert= ed through the worm screw 8 of each single car= rier 2, regardless of the direction of the hooking elements 6 and, consequently, of each single vertical strip of the blind. In fact, in order to achieve perfect parallelism or orientation of all the strips of the blind, it is sufficient just to rotate the control rod 9 in either the directions, until the stop tooth 24 of any one of the hooking elements engages a respective stop surface 25 or 26 on its own carrier. At this point, by rotating the control rod 9 still further, the friction= al device 17, 29 will come into action permitting further rotation of the hooks 6 of the remaining carriers, so as to achieve automatically the precise orientation and perfect parallelism of all the vertical strips of the blind.

Claims

1. Carrier for blinds with swivelling vertical strips, in which each strip of the blind is hanging from a hooking element (6) carried by a sprocket wheel (5), with the possibility of rotating on the axis of the sprocket wheel (5) itself, the latter (5) engaging with a worm screw (8) sliding along a control rod (9),and in which a frictional device is provided bet= ween the hooking element (6) and the sprocket wheel (5), characterized by the fact that the hooking element (6) presents a hook-shaped part (12) provided with a pivoting shank (16) made . of flexibly yielding material, said shank (16) being fitted in an axial hole (30) of the sprocket wheel (5), and by the fact that the hooking element (6) and the sprocket wheel (5) are formed with reciprocally engaging frictional portions (17,29).

2. - Carrier as claimed in claim 1, characterized by the fact that said frictional portions (17, 29) present cylindrical frictional surfaces (18,33) coaxial to the sprocket wheel (5).

3. - Carrier as claimed in claim 2, characterized by the fact that the frictional surface (33) on the sprocket wheel (5), is defined by a cylindrical cavity (32) in the lower portion (29) of the sprocket wheel (5), and by the fact that frictional sur= face (18) on the hooking element (6) is formed on an intermediate portion (17) of the hooking element (6)itself.

4 - Carrier as claimed in claim 3, characterized by the fact that the hooking element (6) comprises a lower hook-shaped part (12), and an intermediate portion extending with a pivoting shank (16) said intermediate portion of the hooking element (6) being provided with flexibly yielding frict= ional elements(17) spaced apart from the side of the shank (16) of said hooking element (6).

5.- Carrier as claimed in claim 4, characterized by the fact that the frictional elements (17) present a circular segment cross-section and ex= tend along part of the length of the shank (16).

6.- Carrier as claimed in Claim 1, characterized by the fact that the shank (16) of the hooking element (6) is axially splitted in its upper part, and by the fact that side protrusions (20) are provided having sloping outer surfaces (21).

7.- Carrier as claimed in claim 1, characterized by the fact that the hooking element (6) comprises an intermediate neck portion (13) shaped with outer shoulder surfaces (14, 15) and with a legnthwise slit (22) for yielding of the neck portion (13), through an assembling hole (7) in a lower wall of the carrier (2).

8. - Carrier as claimed in claim 1, characterized by the fact that the said hooking element (6) comprises a lateral tooth (24) and by the fact that the carrier (2) is provided with stop sur= faces (25,26) for the tooth (24), in diametrically opposed positions.

Drawing