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(11) | EP 1 170 458 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Venetian blind |
| (57) A device (1) for adjusting slats (2) in Venetian blinds (3) which, unusually, is
able to adjust two separate sets (2a, 2b) of slats, comprises a reel (10) on which
a cord (8) for stacking and extending the slats (2) is wound. First and second adjustment
means (6a, 6b) are also provided and are connected to a first (2a) and to a second
set (2b) of slats (2), respectively, by means of cords (5a, 5b). The cord (5a) is
operated by a first element (15) while the cord (5b) is operated by a second element
(32). Both the first and the second elements (15, 32) are coaxial with the reel (10)
and are controlled by the latter. |
[0001] The subject of the present invention is a device for adjusting the position of slats in Venetian blinds and a corresponding Venetian blind.
[0002] As is known, Venetian blinds of the type mentioned above consist of a plurality of slats which can be completely stacked, and therefore in contact with each other, or can be separated out in order to cover the surface area of, for example, a window.
[0003] It is also known that the slats can be adjusted by rotating them relative to a horizontal plane, to give a plurality of positions. These positions range from a position in which the slats are essentially horizontal, and therefore do not obscure the surface area of the window, and a position in which the slats completely obscure the surface area of the window.
[0004] In order to stack or separate the slats winding devices are provided which generally comprise two or more cords secured to the slats. Winding up or unwinding these cords causes the slats to stack up or separate out over the surface area of the window.
[0005] The slats can also be oriented angularly by cords which are secured to the slats. By acting on one end or the other of the cord the slats are rotated relative to a horizontal plane. In particular it is clear from what has been said above that the angular adjustment is the same for all the slats, which are therefore rotated simultaneously and integrally with respect to one another.
[0006] When light levels inside a room are too high, the slats are rotated to give varying degrees of dimming depending on the angle of the slats.
[0007] However, the known types of Venetian blind and their associated adjustment devices do have certain drawbacks.
[0008] It is often necessary to adjust the angle of the slats in order to prevent the sun from directly striking certain parts of the room. In these cases adjusting all the slats as one can cause excessive dimming of the said room. There is therefore the acutely felt need to prevent the sun from directly striking certain areas inside the room without at the same time excessively reducing the levels of light inside the said room.
[0009] The problem underlying the present invention is one of providing a Venetian blind and a device for adjusting the position of slats in Venetian blinds whose structural and functional characteristics are such as to satisfy the abovementioned requirements and, at the same time, to overcome the abovementioned drawbacks cited in reference to the prior art.
[0010] This problem is solved by a device for adjusting the position of slats in Venetian blinds of the type specified above, characterized in that it comprises first adjustment means operationally connected to a first set of slats, so as to adjust their angle, and second adjustment means operationally connected to a second set of slats, so as to adjust their angle.
[0011] This problem is further solved by a Venetian blind of the type specified above, according to Claim 32.
[0012] Further characteristics and the advantages of the Venetian blind and of the device for adjusting the position of slats in Venetian blinds according to the invention will become apparent from the description given below of a preferred embodiment thereof which is given by way of non-limiting example with reference to the appended figures, in which:
Figure 1 illustrates an exploded perspective view of an adjustment device according to the present invention;
Figure 2 illustrates an exploded perspective view like the one in Figure 1 but from a different angle;
Figure 3 illustrates a side view of a detail from Figure 1 corresponding to the winding reel;
Figure 4 illustrates an end view of the detail in Figure 3;
Figure 5 illustrates an end view of a detail from Figure 1 corresponding to a portion of the body seen from the inside;
Figure 6 illustrates an end view of a detail from Figure 1 corresponding to the first element that operates the cord for adjusting the first set of slats;
Figure 7 illustrates an end view of a detail from Figure 1 corresponding to the second element that operates the cord for adjusting the second set of slats;
Figure 8 illustrates an end view of the detail in Figure 7 seen from a position opposite that shown in Figure 7;
Figure 9 illustrates an end view of a detail from Figure 1 corresponding to the first release ring;
Figure 10 corresponds to an end view of a detail from Figure 1 corresponding to the disc associated with the first release ring;
Figure 11 illustrates an end view of the detail in Figure 10 seen from a position opposite that shown in Figure 10;
Figure 12 illustrates an end view of a detail from Figure 1 corresponding to the second release ring;
Figure 13 illustrates an end view of a detail from Figure 1 corresponding to the coupling between the first spring and the first element for operating the cord;
Figure 14 illustrates an end view of a detail from Figure 1 corresponding to the coupling between the first release ring and the first spring;
Figure 15 illustrates an end view of a detail from Figure 1 corresponding to the coupling between the second spring and the third spring and the second release ring;
Figure 16 illustrates an end view of a detail from Figure 1 corresponding to the coupling between the third spring and the second element for operating the cord;
Figures 17 and 18 illustrate a perspective view and a side view respectively of a portion of a Venetian blind according to the present invention.
[0013] With reference to the figures the numeral 1 denotes, as a whole, a device for adjusting the position of slats 2 in Venetian blinds 3.
[0014] Venetian blinds 3 generally consist of a plurality of slats 2 that can be made of different materials, for example of metal or plastic. The slats 2 have an elongate shape along a preferential direction 4 and, transversely to the said preferential direction, can have a flat or curved cross section.
[0015] They are generally positioned one on top of the other over several layers, in a direction perpendicular to the said preferential direction, and are connected together in such a way that both the distance between the slats and the orientation of the slats about the said preferential direction can be varied. The preferential direction is in particular horizontal and the slats are positioned one on top of the other in a vertical direction. The angle of the slats is adjusted by rotating them about a horizontal plane
[0016] In the solution illustrated, the slats are connected together by cords 5a, 5b which are arranged in at least two positions along the preferential direction. Each cord is arranged both in front of and behind the Venetian blind and is attached to each slat 2 along its length. The slats are thus suspended from the said cords and, when the latter are completely extended, the maximum distance between the slats corresponds to the distance between the points at which the slats are attached to the cords.
[0017] Each cord 5a and 5b has a portion which falls in front of the Venetian blind, a portion which falls behind the Venetian blind and folds up above the said blind. At the point where it folds up above the Venetian blind, the cord is controlled by means 6a and 6b for adjusting the angle of the slats.
[0018] More specifically, the slats are grouped together in at least two sets: a first, upper, set 2a and a second, lower, set 2b, each of which is attached to separate cords 5a and 5b. Accordingly, the cords 5a that are connected to the first set 2a are controlled by first adjustment means 6a, while the cords 5b that are connected to the second set 2b are controlled by second adjustment means 6b.
[0019] Furthermore, each slat has at least one slit 7. When the slats are placed in position to form the Venetian blind 3, each slit 7 is positioned in the same vertical direction so that an additional cord 8 can run vertically through all the slats by passing through the slits 7. A stop piece 9 of dimensions larger than those of the slit 7 is secured to the bottom end of the cord 8.
[0020] The cord 8 is controlled by means which stack or extend the slats 2. When the slats are in the most densely stacked position, in which they are in contact with each other and the Venetian blind is therefore completely raised, the cord 8 is at its minimum length and the stop piece 9 is in contact with the bottommost slat of the lower set.
[0021] When the Venetian blind is lowered and the slats are at their maximum distance apart, the cord 8 is at its maximum length and the stop piece no longer engages with the bottommost slat of the lower set. Consequently, by reducing or increasing the length of the cord 8 it is possible to adjust the extent to which the Venetian blind is open, by stacking or extending the slats.
[0022] Two cords 8, which exert a force on at least two points, are preferably provided for stacking or extending the slats. Accordingly, there are at least two series of slits 7, located in two corresponding positions along the preferential direction of the said slats.
[0023] The means for stacking or extending the slats clearly comprise the cord 8 which is wound onto a reel 10. This reel is mounted inside a body 11 which is integral with a fixed structure which supports the Venetian blind 3 at the top.
[0024] The reel 10 is free to rotate relative to the fixed body about a horizontal axis 12. The reel 10 is operated by a drive shaft 12a which is coaxial with the horizontal axis 12 and can be driven by an electric motor 12b or by a manual operating mechanism such as a crank located on the outside of the Venetian blind.
[0025] To this end, the reel 10 has a seat 13 whose cross section matches that of the drive shaft 12a on which the reel is mounted. By rotating the reel 10 in one direction, the cord 8 is wound onto the said reel, the stop piece 9 abuts against the bottommost slat and stacks the slats up. By rotating the reel in the opposite direction, the cord 8 unwinds and the slats 2 separate out in a vertical direction until such a point where they are stopped by the cords 5a or 5b.
[0026] The first adjustment means 6a enable the angle of the first set of slats 2a to be adjusted relative to a horizontal plane. These first adjustment means 6a are operationally connected to the reel 10 in the sense that they are operated by the same drive shaft that operates the reel 10, in a manner that will be described below.
[0027] More specifically, the reel 10 has a first longitudinal extension 10a on which the first adjustment means 6a are mounted and which acts as a drive shaft for the latter.
[0028] These first adjustment means 6a are then inserted between the reel 10 and a portion of the body 11a.
[0029] A spacer member 14 can be mounted coaxially on the first longitudinal extension 10a. Alternatively, the spacer member 14 can be formed inside and in one piece with the body of the reel 10 and in particular of the first longitudinal extension 10a.
[0031] The first element 15 consists of a ring which abuts against the first longitudinal extension 10a of the reel 10 and which has an annular seat 15a for accommodating the cord 5a. More specifically, the accommodating seat 15a has an element 16 for gripping and guiding the cord 5a.
[0032] This first element 15 is rotated by the reel 10 via first drive means which are operationally connected to the reel 10 and to the first element 15 in the manner described below.
[0033] The first drive means consist of a first spring 17 which is inserted between the reel 10, and in particular between the spacer member 14, and the first element 15.
[0034] More specifically, the operational connection between the first spring 17 and the reel 10 is made as a result of the spring tightening around the first longitudinal extension 10a of the reel 10 and thus rotating integrally with it.
[0035] The first element 15 is in addition operationally connected to the first spring 17 via a tooth 18 formed on the internal surface of the first element 15. The tooth 18 is inserted between the ends 17a and 17b of the first spring 17 which extend transversely with respect to the axis 12.
[0036] Rotation of the reel 10 also turns the first spring 17 and, consequently, depending on the direction of rotation of the reel 10, either the end 17a or the end 17b of the first spring 17 abuts against the tooth 18 and turns the first element 15.
[0037] More specifically, the spring is wound in such a way that when the end 17a or 17b - depending on the direction of rotation - abuts against the tooth 18 of the first element 15, the resistance offered by the latter tends to cause the first spring 17 to tighten to an even greater extent on the reel 10.
[0038] This means that the coiling of the spring is such that in the portion corresponding to the tooth 18, the first spring 17 has one more turn than the remaining angular portion where there is no tooth 18.
[0039] The above arrangement means that rotation of the reel 10 also causes the immediate rotation of the first element 15, so that stacking or extending the slats also immediately causes the angular adjustment of the first set 2a of slats. In other words, the act of winding or unwinding the cord 8 also actuates the cord 5a.
[0040] The first adjustment means 6a also comprise first means for engaging or disengaging the first drive means. These first engagement or disengagement means activate or deactivate the operational connection between the reel 10 and the associated first adjustment means 6a; in other words, they activate or deactivate the function performed by the first spring 17.
[0041] The first engagement and disengagement means preferably comprise a first release ring 19 mounted coaxially onto the first longitudinal extension 10a of the reel 10. The first release ring 19 has a cylindrical extension 20 which fits into a corresponding circular seat 21 in the first element 15. The first release ring 19 also comprises two abutment pieces 22 which extend longitudinally with respect to the said ring and with respect to the first longitudinal extension 10a of the reel 10.
[0042] These abutment pieces 22 are positioned slightly outside the two ends 17a and 17b of the first spring 17 relative to the position of the tooth 18.
[0043] The first release ring 19 is rotated with the first spring 17 by means of the abutment pieces 22. If the first release ring 19 is immobilized, one of the ends 17a or 17b of the first spring 17 abuts against one of the two abutment pieces 22 and the first spring 17 tends to open up, thereby losing its grip on the first longitudinal extension 10a of the reel 10. The result is that the first adjustment means 6a, and in particular the first spring 17 and the first element 15, become idle on the reel 10.
[0044] To this end the first engagement and disengagement means additionally comprise a disc 23 which is connected to the first release ring 19 and comprises a cursor 24 which extends longitudinally out from the disc, on the opposite side to that facing the release ring 19.
[0045] The cursor 24 runs along a cam 25 formed on the internal wall of the body 11, and more specifically on a portion 11a thereof which corresponds to the portion housing the first adjustment means 6a. This cam is delimited by blocking members 26 which prevent the cursor 24 from moving beyond these points.
[0046] Immobilizing the cursor 24 has the effect of immobilizing the disc 23 and therefore the first release ring 19 and the two abutment pieces 22. The first spring 17 opens up and remains idle on the first longitudinal extension 10a of the reel 10.
[0048] The disc 23 comprises four projections 27 which extend out longitudinally on the opposite side to that with the cursor 24.
[0049] The wall of the first release ring 19 comprises four slots 28 which extend transversely on one wall of the said ring.
[0050] The four projections are positioned in the four corresponding slots so that, in addition to being driven by the rotation of the first release ring 19, the disc 23 can slide slightly in a transverse direction to the latter. This transverse movement is brought about by the coupling between the cursor 24 and the cam 25.
[0051] The cam 25 has an essentially circular first portion 25a and a second portion 25b in which its profile, and therefore the cursor 24, move towards the horizontal axis 12 along which the reel 10 extends and rotates.
[0052] The second portion 25b continues into a third portion 25c in which the profile of the cam, and therefore the cursor 24, move away from the horizontal axis 12. The cam 25 then continues into a fourth portion 25d which is essentially circular. The first portion 25a starts in the region of one of the blocking members 26, while the fourth portion 25d terminates in the region of the other blocking member 26.
[0053] The second portion 25b and the third portion 25c determine the transverse movement of the disc 23 relative to the first release ring 19. More specifically, the second portion 25b terminates in a steep chute so that, as the second portion connects up with the third portion, the cursor 24 is stopped momentarily at 29.
[0054] This situation corresponds to a position in which the first set of slats remains angled at 38° so as to allow all the slats to stack correctly and, in particular, so as to prevent the cords 5a or 5b from forming loops which will tend to catch between the two sets of slats.
[0055] In order to be able to continue along the cam 25 the cursor 24 has to reverse slightly; thus the entire unit, starting with the reel 10, needs to rotate slightly in reverse. During this reverse rotation the cursor 24 engages with a deflecting member 30 positioned above the cam 25.
[0056] The deflecting member 30 moves the cursor 24 outwards, enabling it to continue along the fourth portion 25d of the cam 25.
[0057] The second adjustment means 6b are also operated by the same drive shaft that rotates the reel 10.
[0058] More specifically, the reel 10 has a second longitudinal extension 10b which extends out on the opposite side to the first longitudinal extension 10a and which represents a shaft on which the second adjustment means 6b are fixed and supported.
[0059] A spacer member 31 is mounted coaxially on the second longitudinal extension 10b of the reel 10. This spacer member can be made in one piece with the reel 10 and in particular with the second longitudinal extension 10b.
[0060] A second element 32 for winding the cords 5b is mounted coaxially on the second extension 10b and is operationally connected to the reel 10 via second drive means.
[0061] The second element 32 consists of a ring which is coaxially mounted onto the second longitudinal extension 10b of the reel 10 and which has a seat 33 for accommodating the cord 5b. More specifically, the accommodating seat 33 has an element 34 for gripping and guiding the cord 5b.
[0062] The second drive means comprise a second spring 35 which tightens around the second longitudinal extension 10b of the reel 10. The second element 32 is held between the reel 10 and the second spring 35.
[0063] The second spring 35 is configured in the same manner as the first spring 17, in other words, it has ends 35a and 35b which extend slightly transversely with respect to the axis 12. The coiling of the second spring 35 is similar to that of the first spring 17.
[0064] A third spring 36 is mounted coaxially on the second longitudinal extension 10b of the reel 10.
[0065] The diameter of the third spring 36 is greater than that of the second spring 35. Moreover, the ends 36a and 36b of the third spring extend radially towards the horizontal axis 12, in contrast to the ends of the first spring 17 and of the second spring 35 which extend outwards with respect to the horizontal axis 12.
[0066] The second drive means also comprise second means for engaging or disengaging the said second drive means. These second engagement or disengagement means activate or deactivate the operational connection between the reel 10 and the associated second adjustment means 6b.
[0067] A second release ring 37 is mounted coaxially on the second longitudinal extension 10b of the reel 10.
[0068] The second element 32 has a tooth 38 which abuts between the two ends 36a and 36b of the third spring 36.
[0069] More specifically, the third spring 36 is wound differently to the other two in that the portion corresponding to the tooth 38 has one less turn than the remaining portion.
[0070] The second release ring 37 in turn comprises a tooth 39 which fits between the two ends 35a and 35b of the second spring 35. The second spring 35 is wound in the same manner as the first spring 17 so that the portion corresponding to the tooth 39 has one more turn than the remaining portion. This means that when the ends of the second spring abut against the tooth 39, the resistance to rotation offered by the second release ring 37 further tightens the second spring 35 on the second longitudinal extension 10b.
[0071] The second release ring 37 comprises two projections 40 which can act on one of the ends of the third spring 36.
[0072] Moreover, the internal wall of the body 11 comprises at least one blocking member 41 which extends longitudinally inwards and can act on the ends of the second spring 35.
[0073] The second spring 35 is rotated by the reel 10. As a result of the interaction between the ends 35a or 35b and the tooth 39, the second spring 35 rotates the second release ring 37. The second release ring turns idly for a time, until such time as one of the projections 40 comes into contact with one of the ends of the third spring 36. The coupling between one of the projections 40 and the third spring allows the latter to be rotated by the second release ring 37. The third spring rotates the second element 32 by means of the tooth 38.
[0074] When the blocking member 41 comes into contact with one of the ends of the second spring 35, the latter opens up and is idle on the second extension 10b of the reel.
[0075] The result of this configuration is that the angular adjustment of the second set 2b of slats is delayed with respect to the first set 2a and terminates when the second spring 35 becomes idle on the second longitudinal extension 10b of the reel 10.
[0076] Locking rings 42 are provided outside the body 11, one on either side, and keep both the first means 6a and the second means 6b longitudinally close together on the extensions 10a and 10b respectively of the reel 10.
[0077] These locking rings 42 are inserted between the external wall of the body 11 and a number of small teeth 43 which project slightly beyond the body 11 and which are formed by the ends of the two longitudinal extensions 10a and 10b.
[0079] The drive shaft (not illustrated) turns the reel 10 and therefore, integrally with the latter, the first spring 17 and the second spring 35 which are tightly wound on the first and on the second longitudinal extensions respectively of the reel.
[0080] The first spring 17 transmits the motion to the first element 15, as a result of which the cord 5a brings about the angular adjustment of the first set 2a of slats 2.
[0081] This adjustment is interrupted when the cursor 24 abuts against a blocking member 26 or against the momentary blocking member 29.
[0082] When the cursor 24 abuts against one of the blocking members 26, the first set 2a is in one of its extreme positions: i.e. with the slats essentially horizontal or with the slats at their maximum angle relative to the horizontal plane, for example so that the Venetian blind completely obscures the window at which it hangs.
[0083] When the cursor 24 abuts against the momentary blocking member 29, the first set 2a - in other words the upper set of slats - stops at an angle of approximately 38° with respect to the horizontal.
[0084] In order to close the slats once again, the reel 10 needs to be rotated slightly in reverse, thereby releasing the cursor 24. The latter can then pass over the momentary blocking member 29 and continue along the cam 25 as far as the next blocking member 26.
[0085] The start of the angular adjustment of the second set 2b is delayed as a result of the angular position of the projections 40 relative to the ends 36a or 36b of the third spring 36.
[0086] The second longitudinal extension 10b rotates the second spring 35. The latter drives the second release ring 37 as a result of the interaction between the tooth 39 and the ends 35a and 35b of the second spring 35. When the projections 40 abut against one of the ends 36a or 36b of the third spring 36, the latter is driven by the second release ring 37 and tightens around the second element 32. As a result of the interaction between the third spring and the tooth 38 on the second element 32, the latter is rotated about the horizontal axis 12, driving the cord 5b and thus adjusting the angle of the second set 2b of slats 2.
[0087] When one of the ends of the second spring 35 abuts against one of the blocking members 41, the second spring 35 tends to open up and to become idle on the second longitudinal extension 10b. The angular adjustment of the second set 2b is thus complete.
[0088] From the description given above it may be appreciated how the novel provision of first and second adjustment means 6a and 6b makes it possible to adjust the angle of at least two sets of slats independently of each other.
[0089] As may be appreciated from the description given, the adjustment device and the Venetian blind according to the present invention make it possible to satisfy the abovementioned requirement of adjusting the light levels inside a room, allowing selective adjustments to be made at those points where it is necessary.
[0090] One advantage of the abovementioned selective adjustment is that such adjustment can be effected using the same means as those used to stack and extend the slats, thereby avoiding the need to introduce structural and/or functional complications. The presence of drive means and associated engagement and disengagement means, however, enable the angular adjustment mechanism to be partially independent of the means for stacking or extending the slats, especially with regard to the moment at which the said adjustment begins and ends.
[0091] A further advantage of the device according to the invention lies in its uncommonly simple structure, which enables the said device to be produced at a very low cost.
[0092] Needless to say, variations and/or additions can be made to the details described above and illustrated.
[0093] Alternatively to the embodiment illustrated in the figures, the spacer members 14 and 31 can be made in one piece with the reel 10.
[0094] A person skilled in the art may, in order to satisfy contingent and specific requirements, make numerous modifications and adaptations to the preferred embodiment of the device or of the Venetian blind described above and may substitute certain elements with other, functionally equivalent, ones without thereby departing from the scope of the following claims.
1. Device (1) for adjusting the position of slats (2) in Venetian blinds (3) comprising
means (10) for stacking and extending the slats (2), characterized in that it comprises:
first adjustment means (6a) operationally connected to a first set (2a) of slats (2), so as to adjust their angle; and
second adjustment means (6b) operationally connected to a second set (2b) of slats (2), so as to adjust their angle.
2. Device according to Claim 1, in which the first adjustment means (6a) are operated
by the means (10) for stacking and extending the slats (2).
3. Device according to one of the preceding claims, in which the second adjustment means
(6b) are operated by the means (10) for stacking and extending the slats (2).
4. Device according to one of the preceding claims, in which the means (10) for stacking
and extending the slats (2) comprise a cord (8) which is operationally connected to
the slats (2), the length of which can be varied in order to vary the extent to which
the slats (2), and therefore the Venetian blind (3), are stacked or extended.
5. Device according to Claim 4, in which the cord (8) runs inside slits (7) formed in
the slats (2) and comprises a stop piece (9) at the bottom which engages with a bottommost
slat.
6. Device according to Claim 4 or 5, in which the means for stacking and extending the
slats (2) comprise a reel (10) on which the cord (8) is wound, the said reel rotating
about an axis (12).
7. Device according to one of the preceding claims, in which the first adjustment means
(6a) comprise at least one cord (5a) along which the slats (2) of the said first set
(2a) are attached.
8. Device according to Claim 7, in which the said first adjustment means (6a) comprise
a first element (15) that operates the cord (5a) and rotates about an axis (12).
9. Device according to Claims 6 and 8, in which the said first element (15) is rotated
by the reel (10).
10. Device according to Claim 9, in which the said first element (15) is idly mounted
on a first longitudinal extension (10a) of the reel (10) and is rotated by the said
reel via first drive means (17).
11. Device according to Claim 10, in which the said first drive means comprise a first
spring (17) which is wound onto the first longitudinal extension (10a) and is operationally
connected to the first element (15).
12. Device according to Claim 11, in which the first element (15) comprises a tooth (18)
which is inserted between the ends (17a, 17b) of the first spring (17), which ends
extend transversely away from the latter.
13. Device according to Claim 12, in which the first spring (17) is wound in such a way
that it tightens around the first longitudinal extension (10a) as a result of the
interaction between one of the ends (17a, 17b) and the tooth (18).
14. Device according to one of Claims 10 to 13, in which the first adjustment means (6a)
comprise first means for engaging and disengaging (19, 23, 24, 26) the first drive
means (17).
15. Device according to Claim 14, in which the said first engagement and disengagement
means comprise:
a release ring (19) which can be operationally connected to the first spring (17); and
a cursor (24) which is rotated by the release ring (19) and engages with fixed blocking members (26).
16. Device according to Claim 15, in which the release ring (19) comprises two abutment
pieces (22) which, relative to the tooth (18), are positioned outside the ends (17a,
17b) of the first spring (17).
17. Device according to Claim 15 or 16, in which the said first engagement and disengagement
means additionally comprise a disc (23) which is rotated by the release ring (19)
and is integral with the said cursor (24).
18. Device according to Claim 17, in which the cursor (24) slides in a fixed cam (25)
and in which the disc (23) can slide transversely with respect to the release ring
(19).
19. Device according to Claim 18, in which the cam (25) comprises a position (29) in which
the cursor (24) is stopped momentarily.
20. Device according to one or more of the preceding claims, in which the said second
adjustment means (6b) comprise at least one cord (5b) along which the slats (2) of
the said second set (2b) are attached.
21. Device according to Claim 20, in which the said second adjustment means (6b) comprise
a second element (32) that operates the cord (5b) and rotates about an axis (12).
22. Device according to Claims 6 and 21, in which the said second element (32) is rotated
by the reel (10).
23. Device according to Claim 22, in which the said second element (32) is idly mounted
on a second longitudinal extension (10b) of the reel (10) and is rotated by the said
reel via second drive means (35, 36, 37).
24. Device according to Claim 23, in which the said second drive means comprise a second
spring (35) which is wound onto the second longitudinal extension (10b) and is operationally
connected to the second element (32).
25. Device according to Claim 24, in which the second drive means comprise a second release
ring (37) which is operationally connected to the said second spring (35) and a third
spring (36) which is operationally connected to the said second release ring (37)
and to the said second element (32).
26. Device according to Claims 25, in which the second release ring (37) comprises a tooth
(39) which fits between the ends (35a, 35b) of the second spring (35).
27. Device according to Claim 25, in which the said second release ring (37) comprises
at least two projections (40) which act on one of the ends (36a, 36b) of the third
spring (36).
28. Device according to Claim 27, in which the projections (40) are located in an angular
position such that they delay the start of rotation of the second element (32) relative
to the start of rotation of the reel (10).
29. Device according to Claim 25, in which the second element (32) comprises a tooth (38)
which fits between the ends (36a, 36b) of the third spring (36).
30. Device according to one of Claims 23 to 29, in which the second adjustment means (6b)
comprise second means (41) for engaging and disengaging the first drive means.
31. Device according to Claim 30, in which the said second engagement and disengagement
means comprise at least one fixed blocking member (41) which acts on one of the ends
(35a, 35b) of the second spring (35).
32. Venetian blind comprising a device (1) for adjusting the position of slats (2) according
to Claims 1 to 31.