FI98851C - With a device controllable damper curtain - Google Patents

Abstract

Headrail hardware to lift and tilt a Venetian blind is provided. A single control (5) operates both the lift and the tilt function. A multiturn band brake tilter (19) is used with each ladder cord (15) in a way that reduces the frictional forces encountered in lifting or lowering the blind. One end of each of the ladder cords is attached to an arm (21) of its tilter. The tilters are disposed directly about the rotating drive rod (11) with no intermediate parts, and are supported by cradles (17) that mount in the headrail rather than by the drive rod (11) as in prior art blinds. The drive rod (11) rotates the tilters (19) and the lifting mechanism until the tilters (19) contact stops built into each of the cradles (17). Further rotation keeps the blind fully tilted while lifting or lowering of the blind continues. In the preferred embodiment, the lift cords (13) are attached to the drive rod (11), which traverses to accumulate the cords (13) in a single layer as the rod (11) is rotated to lift the blind. The rotation of the rod (11) within the tilters (19) greatly reduces the lateral force needed to traverse the rod (11). An innovative bearing support (41) is provided so that the weight of the blind is transferred from the tilter (19) directly to the cradle (17), further reducing the frictional drag on the traversing rod (11).

Description

98851

Shutter blind adjustable with one device

The invention relates to a single device adjustable louvre tilting and lifting system according to the preamble of claim 1.

The slat blind rail mechanism must provide two functions: first, raising and lowering the curtain, and second, adjusting the slope tilt to open or close the curtain or set the slats to the desired angle. The ideal single-device adjustable rail mechanism would require little force even when lifting heavy and long louvers. It would take care of assembling the traction braid or cords into a relatively small rail mechanism. It should have a tilt mechanism that allows for good closure. Finally, it would comprise a minimum number of parts, be easy to assemble, and require a minimum number of adjustments.

Numerous models of blinds that can be adjusted with one device are known in the prior art. Some niis-20 are not tilted enough for the closure to be good. Many of them use numerous complex components and are difficult to adjust.

The prior art discloses two general methods for assembling drawstrings or strips. 25 to the mechanism. One method is to wind the traction braids or cords on the spools. There are two disadvantages to this method. First, the braids or strips do not wind evenly on the spools, and a very small difference in diameter produces an easily noticeable unevenness in the blind when it is lifted. Second, the mechanical benefit of the lifting mechanism decreases as the amount of tape or braid accumulating in Poland increases. This progressive decrease in mechanical gain occurs when the lifting braids support a greater portion of the weight of the curtain, resulting in a greater increase in the required force to further lift the curtain. The mechanical benefit decreases just when it should increase.

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Another and more preferred method is to collect the braids on a shaft that moves laterally or transversely so that the lifting braids rotate into a single layer on the shaft. This ensures an even rotation 5 of each lifting braid, keeping the mechanical benefit constant so that the lifting force increases only in proportion to the weight supported by the lifting braids. Several methods have been used to produce transverse movement of the rod, for example a rack arrangement. U.S. Patent 1,343,527 describes a transverse movement of a lead screw and nut. Another method, which does not use gear mechanisms or guide screws, is described in U.S. Patent 4,625,012, in which lifting braids, by affecting the cam characteristics of the supports supporting them, produce transverse forces for transverse movement of the rod. Although this method is currently used in several blinds rising from below, it was not believed that the method could work in roller blinds because it was expected that the weight of the blinds dependent on the control devices would increase friction so much that the bar would not move transversely properly.

The rail mechanism must also take care of tilting the slats of the blinds. In a single-adjustable blind, a transverse bar is used, in which, in order to collect the lifting braids, the tilting mechanism must rotate in either direction along the transverse bar until the fully closed position is reached. Thereafter, the tilt mechanism must slide while holding its position while raising or lowering the blind. In a single-adjustable louvre with a cross bar, the drive shaft of the tilt mechanism is a transverse bar. The blind strips are connected to an adjustment mechanism. Generally, a single-adjustment louvre has one adjustment mechanism for each blind strip. The best tilting results are obtained if the blind strips are attached to the adjusting device with a distance 35 between the strips equal to the width of the slats. In addition, the line between these attachment points should li 98851 3 run along the centerline of the transverse bar. This keeps the adjuster at the same angle as the slats. If this geometric ratio is not maintained, it is necessary to achieve this closed position that the tilting mechanism 5 is able to raise the blind.

In louvered blinds in which the lifting mechanism and the tilting mechanism are separate, it is not difficult to produce a tilting mechanism capable of lifting the entire weight of the blind. However, in a transverse single-blind louvre 10, the transverse bar must use both tilting and lifting mechanisms. When the fully tilted position is reached, the tilt mechanism must be partially disengaged and slide. This produces sufficient torque to maintain a full tilt as the rod 15 continues to rotate to raise or lower the blind. Any force required to maintain full tilt is added to the force required to raise the blind. This force is at a minimum if (a) the geometry of the adjusting device is as described above and (b) 20 if the adjusting mechanism is able to adjust its grip on the transverse bar to produce only the torque required to maintain full tilt. In addition, the smaller the difference between the blind strips on different sides, the better the closure. The latter 25 requirement is best met if the adjusting devices are mounted directly on the crossbar. The middle part between the adjusting devices and the bar increases the difference between the blind strips during full tilting. U.S. Patent 4,697,630 discloses an adjustment mechanism that has good gripping torque between the extremities of the tilt while partially releasing its grip after reaching full tilt. This adjusting device is made in the form of a multi-turn helical band switch which engages the transverse bar during tilting. When the fully tilted position is reached, the front end of the adjuster contacts the stop, which prevents the adjuster from moving further and partially releases the grip of the adjuster from the rod, thereby limiting the frictional resistance of the adjusters from the rod by exactly the torque required to hold the blind fully tilted. The rod can continue to rotate by winding 5 or unwinding the lifting braids, lowering or raising the blind according to the direction in which the rod is rotated.

U.S. Patents 2,737,235, 2,758,644 and 3,352,349 describe prior art single device adjustable blinds using a variety of transverse bar lifting mechanisms. In order to achieve the transverse movement of the blinds according to the prior art, it is necessary to overcome the frictional force acting on the transverse rod due to the weight of the curtain. The grip of the tilting mechanism on the transverse bar must be sufficient to ensure complete closure. Of course, both the tilting force and the resistance of the rod must be overcome in order for the rod to move transversely. These frictional resistances are too high, making these blinds very difficult to use. It is therefore not surprising that Venetian blinds using this type of mechanism 20 have never become popular.

It is an object of the present invention to obviate the drawbacks of the prior art. This object is achieved by a system according to the invention, which is characterized in that the support stop further has a surface for supporting the adjusting device in order to reduce the frictional resistance to the rod.

The desired features of the helical belt adjusting device of U.S. Patent 4,696,630 can be combined with the transverse bar system of U.S. Patent No. 4,623,012 to provide a louver blind that can be operated with a single adjusting device and that assembles the drawstrings within the rail mechanism. This combination has been tried and found to be unsatisfactory because the adjusting devices affect the frictional resistance 35 so much on the transverse rod that the rod does not move transversely reliably. The invention comprises a new support surface 5. 98851, which eliminates much of this frictional resistance. In a preferred embodiment, the band switch of U.S. Patent 4,697,630 is modified so that the adjusting device is supported directly on the support stop instead of the transverse rod. This 5 significantly reduces the frictional forces on the transverse rod, which improves the reliability of operation. The blind is good to close, it is easy to raise and lower. It has few parts, is easy to assemble and easy to adjust. The combination of the invention has advantages in both the adjustment mechanism and the lifting mechanism without the rod sliding against the high frictional forces observed in prior art blinds.

The use of a helically rotating belt clutch adjuster is crucial because it alone, among the various known single device adjustable blinds, can produce high friction during adjustment, while being able to adjust the frictional forces between the adjusters and the transverse bar to the minimum required. 20 sex. Other methods that use a predetermined frictional connection between the rod and the tilting device must, due to the variability in the frictional forces, produce an additional frictional force to ensure complete closure of the blind. This additional force undesirably increases the force required to operate the blind. U.S. Patent 3,352,349 discloses a single device controlled louvre using a transverse bar and an adjusting device that engages the transverse bar by frictional force. The traction rope support 15 is mounted to be slightly compressed on the drive shaft 2. But experience has shown that the adjusting device must grip the drive shaft tightly during tilting to achieve good closure, and the friction resulting from this tight grip requires high forces from the transverse mechanism to slide the shaft.

35 In a fully extended louver, the blind straps support the entire weight. When the blind is raised, the weight of the 98851 6 is transferred to the tow ropes. When the blind is fully raised, the tow ropes actually support the entire weight of the slat stack and bottom rail. The blind strips are attached to the adjusting devices, so that what supports the adjusting devices 5 must also support the weight of the pulled-out part of the blind. The normal forces between the adjusting devices and their supports and the friction they generate can make transverse movement difficult when the blind is pulled almost for a long time. At that time, the adjusting devices support most of the weight, producing maximum friction, and the tension of the traction ropes required to produce transverse movement is minimal.

It is surprising that it is possible to produce sufficient control driving force without loading the transverse mechanism with such high friction that transverse movement is prevented. 15 This is because the force required to produce movement between two frictionally connected objects is greater if only that force is active than if another force causes the movement, even if that force is in a different direction. For example, referring to Figure 1, the force F1 required to dissolve an object of 20 W over a horizontal surface is equal to uW, where u is the coefficient of friction between the surface and the object. But, if the object moves under the effect of two forces perpendicular to each other F1 and F2, then the vector sum F1 + F2 is equal to uW, and as shown in Fig. 2, where A is the angle between F2 and the actual direction of motion. In this case, both F1 and F2 are smaller than uW and if the angle A is small, F1 is much smaller than uW.

In our case, F2 corresponds to the force 30 rotating the rod, which forces it to slide inside the adjusting device, and F1 corresponds to the force required to move the rod transversely. In a typical embodiment of the invention, a rod with a diameter of 9.525 mm is used and the diameter of the tow rope is about 1.016 mm. Because the rod rotates one full-35 den revolution, while it only moves transversely

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98851 7 distance corresponding to the thickness of the string, the surface movement in the direction of rotation is about 30 times larger than the transverse movement, which makes the angle A quite small, i. slightly below 2 degrees. In this case, the force F2, which ai-5 throws the rotational motion, performs most of the anti-friction motion, and F1 is only about 3% of what it should be to cause transverse motion if F2 were not affected. In a blind with an intermediate part between the control device and the strip housing, the full amount of work must be performed at each connection point, i.e. between the control device and the housing and the housing and the rod. Since the blind user must produce the entire amount of work, this greatly increases the force required to operate the blind.

It has been found necessary in very long blinds using the adjusting device of U.S. Pat. No. 4,697,630 to increase the weight of the bottom rail to ensure that the transverse bar returns fully to its initial position. In a preferred embodiment of our invention, a great improvement is achieved by changing the adjusting device and the support stops so that the adjusting device is supported directly on the sliding surface of the support stop rather than on the transverse rod. Improved performance results from a reduction in the formal forces between the rod and the adjusting devices. This greatly reduces the force required to move the rod. In the previous system, the force required for transverse motion increased just as the force available for transverse motion decreased. In this preferred embodiment, while the force available for transverse movement still decreases as the blind is lowered, the frictional force that prevents transverse movement of the rod remains constant and small.

Accordingly, it is an object of the invention to provide a single-device adjustable lifting and tilting mechanism for a slatted blind, the use of which requires a minimum force and which maintains its mechanical benefit constant during lifting.

Another object of the invention is to provide a single-device adjustable lifting and tilting mechanism for a Venetian blind 98851 8, in which the operating effort when lifting long and heavy blinds is low.

Yet another object of the invention is to provide a single device adjustable lifting and tilting mechanism for a louvre blind which is capable of lifting long blinds with a relatively small rail mechanism.

Yet another object of the invention is to provide a single device adjustable lifting and tilting mechanism for a louvre blind that is capable of applying sufficient torque to ensure good closure.

Yet another object of the invention is to provide a single device adjustable lifting and tilting mechanism for a louver that allows close contact of the blind strips in fully tilted positions.

Yet another object of the invention is to provide a single-device adjustable lifting and tilting mechanism for a louvre blind, in which it is not necessary to react to the total torque required for tilting when the blind is raised.

Yet another object of the invention is to provide a single-device adjustable lifting and tilting mechanism for a Venetian blind with a minimum number of parts that is easy to assemble and adjust for proper operation.

Other objects, features and advantages of the invention will become apparent from the following detailed description and accompanying drawings, in which: Fig. 1 is a vector diagram of a force F1, in this case equal to uW, required for transverse motion when not affected by other forces; Fig. 2 is a vector diagram of the forces F1 and F2 and 30 of their resultant force uW, where F1, now much smaller than uW, is the force required for transverse movement when other movement was acting on the same interface, Fig. 3 is an isometric view of the shutter rail mechanism 35 cut off to expose the parts inside,

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Fig. 4 is an enlarged view of a portion of the machine of Fig. 3 showing the details of the lifting and tilting portions and the inventive feature of a preferred embodiment of the invention; Fig. 5 is an enlarged side view and a partial cross-sectional view of a prior art lifting and tilting mechanism; it shows a control device, a crossbar and a support stop, Fig. 6 is a corresponding view of the same components, but in this case the control device is supported on the support response according to the principles of the present invention, Fig. 7 is a view similar to Fig. 5 of the same components but shown during blind raising. rotated 90 degrees, and Figure 8 is an enlarged side view and a partial cross-sectional view of another embodiment of the invention using a spool and a string or tape to raise the blind.

The general organization of the lifting system 20 inside the rail mechanism can be seen in Figure 3. The rail mechanism 1 may be of any suitable cross-section, as long as there is sufficient space inside it for the equipment. The holding mechanism 3, which could be a device of various shapes, is preferably mounted at the end of the rail mechanism 25 1, although other locations are possible.

A suitable drive device is required to drive the holding device 3. In this case, a string loop 5 is shown, although many other combinations of holding mechanism and drive could be used instead. The outlet of the holding mechanism 30 has grooves 7. The grooves 7 together with the disc 9 connected to the transverse rod 11 form an axially sliding torque-bearing connection between the holding mechanism 3 and the transverse rod 11. The particular groove and disc arrangement shown herein for connection to a holding mechanism is intended only as an example, and other means of making the connection 98851 10 may be used without departing from the object and content of the invention.

The other parts inside the rail mechanism are connected to the attachment, adjustment 5 and operation of the traction cord 13 and the blind strip 15. One such set would normally take care of one set of lifting rope and blind strap. Descriptions of parts and forces and operation have been made for one such set of lifting and adjusting components, which is then applicable to other sets as well. In some blinds, a partial set of components may be used at one of 10 or more points. For example, blinds usually have three blind straps but only two drawstrings. This is the case when two tow ropes are sufficient to raise the blind, but a middle blind strip is still needed to support the weather properly. In such cases, the operation of the blinds remains the same because it applies to components of an incomplete set.

The support stop 17 and the adjusting device 19 are generally mounted in accordance with the principles of U.S. Patent 4,697,630. 20 of each side of the ladder cord 15 is attached to the second control unit 19 of the two arms 15, as shown in Figure 4 can be seen. The traction rope 13 is generally mounted in accordance with the principles of U.S. Patent 4,623,012, coming through a support on the lower surface of the rail mechanism, then passing 25 over the roller 23, as shown in Figure 5, and ending to be attached to the rod 11 by a holder 25 or other suitable device.

Figure 5 shows a prior art combination of a transverse stripping system in accordance with the principles of U.S. Patent 4,623,012 and a helical belt adjusting device in accordance with the principles of U.S. Patent 4,697,630. The transverse rod 27 is supported directly on a support stop 29, the sliding surface 31 of which is shaped to fit the rod 27. The adjusting device 33 is positioned and fully supported around the rod 27.

98851 11

Figure 6 shows the adjustment and lifting components of the invention with the slats in a horizontal position. In this figure, the arms 21 shown in Figure 4, omitted from Figure 5 for clarity, would be horizontal in the Plane 5 passing through the center of the rod 35. The adjusting device 37 is wound around the rod 35, as in the previous embodiment, but in this case the adjusting device has a sliding surface 39 resting on the sliding surface 41 of the support stop 43. The flange 45 at the end of the adjusting device 37 forms an obstacle 10 preventing the adjusting device 37 from moving axially along the support stop 43 . The outer surface of the flange 45 is angled to form a guide cam surface 47 in accordance with the principles of U.S. Patent 4,623,012. The angle is shown in Figure 6 as angle A. The desired size of angle A depends on the ratio of the diameter of the traction cord 47 to the diameter of the rod. The guide cam must produce sufficient movement to provide space for the incoming rope so that the rope does not overlap with previous turns. When the blind is fully lowered and most of the blind weight 20 depends on a plurality of blind strips on the blind, a very small portion of the blind weight is supported on the surface between the rod 35 and the control device 37. Instead, most of the weight is supported on the bearing surface 41 between the support stop 43 and the adjusting device 37. This reduction in the frictional resistance between the adjusting device and the transverse band allows the rod to move much more easily. Due to the better support surface of this adjusting device 37, it is necessary to tighten the tow rope much less in order to ensure that the transverse rod 35 is fully returned to its initial position when the blind 30 is fully lowered.

Fig. 7 shows the same components as in Fig. 6 when the blind is raised. As the traction cord 49 rotates around the rod 35, it contacts the guide cam surface 47, forcing the rod 35 to move to the left away from the pin of the guide cam pin 35. The adjusting device 37 is fully rotated to the limit allowed by the stop-pair 51, which detaches the grip of the adjusting device 98851 12 from the rod 35, keeping only sufficient grip to maintain the orientation. In this position, the arms 53 are approximately vertical and the blind strips, of which only the second, closer strip 55 is visible, are in a fully tilted position.

The mechanism of U.S. Patent 4,632,012 does not have an adjusting device. The guide cam surface is formed as part of the support response. In the invention, the string comes into contact with the flange of the control device. Therefore, it is necessary for the si-10 to retain the cam surface on this flange. One characteristic of the blind of the invention is that it can be raised by rotating the rod in either direction. This requires that the cam surface be on the right side when the blind is raised by turning the rod counterclockwise and on the left when 15 turns occur in the other direction. When the blind is raised, the control unit rotates 90 degrees in the direction of rotation of the rod. This orients the cam surface 47 correctly for that direction of rotation of the traction cord. The cam steering effect occurs in an arc of about 120 ° between the point where the cord first contacts the shaft-20 and the upper end of the shaft. When the adjusting device 37 is horizontal, as seen in Fig. 6, the cam surface 47 hits the lower part of the flange 45. When the adjusting device rotates 90 degrees in one direction or another, the cam surface rotates to the required position.

In another embodiment of the invention, the adjusting devices are also supported directly on the support stops, rather than on a rod, which in this case does not move transversely, but simply rotates. In this type of single-device adjustable blind, lifting is performed by twisting the tape or string on the spools. Although this type of blind does not have a transversely movable bar, it is important to reduce operating friction and a great deal of effort has been put into it, even to the extent that production machining has been replaced several times to achieve small improvements in the "feel" of blinds made with this equipment. Fig. 8 shows lifting and adjusting components 98851 13 for this embodiment, which correspond to the components of the preferred embodiment shown in Figs. 5 and 6. An adjusting device 59 is arranged around the rod 57. The adjusting device 59 has a sliding groove 61 which rotates on and is supported on the support surface of the support stop 5. The support stop 65 is similar to the support stop 37 of the preferred embodiment, except that instead of a roller, the traction cord guide has a notch 67 which guides the cord or tape 69 to the spool 71. Since there is no transversely movable rod in this case, the spool 10 71 is firmly attached to the rod 57 rotates with it. As before, the adjusting device 59 must rotate with the rod 57 until it reaches the stopper. It must then remain in position and maintain a full tilt, while the rod 57 continues to rotate to raise or lower its si-15 blind. Friction adjustment is important in this case to ensure that the adjusting device has a sufficient grip on the rod 57 to produce a full tilt. But the extra frictional resistance between these parts simply increases the operating effort of the blind 20. Significant savings in operating effort are achieved by transferring the support load from the rod 57 to the support surface 63 of the support stop 65. Since the rod does not move transversely, a guide cam surface is not required and the outer surface of the flange 73 of the control device 59 may be perpendicular to the shaft 57.

It has been found that the objectives set have been practically achieved. Certain changes can be made to the construction of the spring coupling according to the invention without departing from the spirit and scope of the invention, so that it is clear that all the material contained in the previous description and shown in the accompanying drawings is to be construed as illustrative only and not restrictive.

Claims (14)

98851 14 A combined, single-device adjustable slat blind tilting and lifting system, comprising: 5 transversely movable rods (27; 35; 57) rotating in two directions along its axis, at least one multi-rotating adjusting device engaging the rod (27; 35 ; 57) and connected to the blind strips (55) of said blind, means for at least partially disengaging the adjusting device (33; 37; 59) from the rod (27; 35; 57) at positions where full tilt in either direction of rotation is achieved, at least one traction cord (49) connected to a rod (35) and which, as the rod rotates, rotates around or opens from the rod (35), means for applying a lateral force to the transversely movable rod (35) in a first direction as the traction rope (49) rotates about the rod (35). ), the devices for supporting the transversely movable rod (35) comprise at least one support stop (29; 43; 65) having a surface which takes against the rod and located approximately where the at least one traction cord (49) engages the rod (35), characterized in that the support stop (43) further has a surface for the adjusting device (33; 37; 59) to reduce frictional resistance to the rod (27; 35; 57). A system according to claim 1, characterized in that the release device comprises means for preventing rotation of the adjusting member in fully tilted positions. A system according to claim 2, characterized in that the blocking devices comprise at least one stopper (51) for releasing the grip of the adjusting device (37) from the rod (35) in fully tilted positions. Il 98851 15 A system according to claim 1, characterized in that the at least one adjusting device comprises a central part shaped to engage the rod and two arms (53) for receiving the ends 5 of the blind strips (55). System according to Claim 1, characterized in that the at least one control device (37) is flexible. A system according to claim 1, characterized in that the inner diameter of the at least one adjusting device (33; 59) is approximately the same as the outer diameter of the rod (27; 57) so that the weight of the louver causes the at least one adjusting part (33; 59) to tighten 27; 57) around. System according to Claim 1, characterized in that the at least one adjusting device (33; 59) is mounted directly on the rod (27; 57) without an intermediate part. A system according to claim 1, characterized in that the support stop (65) comprises an opening through which the blind strip passes. A system according to claim 1, characterized in that the drive means comprise a guide cam surface (47) against which the traction rope (49) rests, which enables the rod (35) to move laterally in the first direction. A system according to claim 9, characterized in that the guide cam surface (47) is shaped so that rotation of the transverse rod (35) to rotate the traction cord (49) around it causes the rod (35) 30 to move laterally. A system according to claim 10, characterized in that the guide cam surface (47) is shaped so that the rotation of the rod (35) rotates the traction rope (49) around the rod (35) in one layer. A system according to claim 1, characterized in that the at least one adjusting part (59) 98851 16 comprises a projecting flange (45) for maintaining the axial position of the adjusting device relative to the support stop (43). A system according to claim 12, characterized in that the flange comprises a guide cam surface (47) against which the traction rope (49) rests so as to allow the rod (35) to move transversely. A system according to claim 13, characterized in that the guide cam surface (47) of the flange (45) is arranged at an angle which depends on the dimensions of the rod (35) and the traction rope (49). Il 98851 17