Screen roller blind

Abstract

 Screen roller blind (12) provided with a frame (10a) comprising: a roller (11) on which said screen (12) can be wound and unwound (12); rails (13) extending from the roller (11) along an extension direction (A); a crosspiece (14) developing along a development direction (B) perpendicular to the extension direction (A) of the rails (13), and selectively sliding along the extension direction (A) of the rails (13) according to an unwinding direction (C) of the screen (12), or according to a winding direction (D) of the screen (12).
Moreover, the screen roller blind (10) comprises a blocking device (100) which comprises a blocking element (15) mechanically connected to an end (14a, 14b) of the crosspiece (14) and provided with at least an extension (15a) elongated in a projecting direction (F) substantially perpendicular to the development direction (B) of the crosspiece (14), the blocking element (15) being able to oscillate with respect to the crosspiece (14), according to an axis of oscillation (E) substantially parallel to the development direction (B) of the crosspiece (14), between a locking position in which the extension (15a) is partially facing towards the winding direction (D) of the screen (12), and an unlocking position in which the extension (15a) is partially facing towards the unwinding direction (C) of the screen (12). This blocking device (100) also comprises at least a stopping block (16) fastened to one of the rails (13), susceptible of being engaged by the blocking element (15) to prevent the crosspiece (14) from sliding in the winding direction (D) of the screen (12), and a counter-thrust portion (17) mechanically connected to the crosspiece (14) and susceptible of abutting on the guide (13), upon the engagement of the blocking element (15) with the stopping block (16), to keep the blocking element (15) interfering with the stopping block (16).

Description

Field of application

[0001] The present invention relates to a screen roller blind according to the preamble of the independent claim.

[0002] The subject screen roller blind is intended to be advantageously used for adjustably covering the openings of buildings such as windows, doors, skylights and the like, or for closing balconies, porches or other spaces that require a protection against the wind, the sun and more in general, the external environment.

[0003] The present screen roller blind preferably is of the type with drop screen, i.e. intended to close an opening by sliding with a vertical movement along longitudinal guiding beams starting from a winding roller arranged on top of the same opening.

[0004] Such screen roller blind is therefore intended to fall within the industrial field of the production of building accessories, and in particular in the field of door and window frames and in the field of blind production for sun protection, or of insect screen production and similar applications.

Prior art

[0005] Screen roller blinds or similar devices such as shutters, are known on the market, which are provided with blocking devices susceptible of blocking the screen in a deployed position.

[0006] A shutter is known from patent EP1975367, which is provided with a screen blocking device susceptible of blocking the same screen in an extended position.

[0007] More in detail, such shutter is provided with a frame which comprises a roller on which the shutter screen is susceptible of being wound and unwound, two rails on the sides of the roller and extending from the roller along an extension direction and a crosspiece having the ends slidably connected to the rails along the extension direction of the same rails.

[0008] The crosspiece has a prevailing development direction which is transversal to the extension direction of the rails and is fastened to a free edge of the screen for guiding the screen parallel to the extension direction of the rails.The blocking device described in such patent EP1975367 comprises blocking elements projecting from the ends of the crosspiece and rotatably connected thereto around an axis of rotation which is parallel to the development direction of the same crosspiece.

[0009] These blocking elements have extensions extending relative to the axis of rotation of the blocking elements according to a projection direction which is substantially radial to the same axis of rotation, so that subsequent to a rotation of the blocking elements, around their axis of rotation, the projection direction correspondingly rotates.

[0010] Moreover, the above blocking device comprises hooking elements fastened within the rails and susceptible of being engaged by the blocking elements for preventing the sliding of the crosspiece along the rails towards the roller.

[0011] In particular, these hooking elements are mutually facing and thereinbetween define, in each rail, a passage for a corresponding one of the hooking elements.

[0012] The blocking device described in such patent EP1975367 also comprises a cam device fastened to the rails and susceptible of rotating the blocking elements around their axis of rotation between an unlocking position, wherein said extensions have the projection direction substantially parallel to the extension direction of the rails, and a locking position wherein the extensions have the projection direction substantially perpendicular to the extension direction of the rails.

[0013] In such unlocking position, the blocking elements are susceptible of freely sliding into the passage between the above hooking elements, on the contrary in said locking position the hooking elements are susceptible of interfering with the hooking elements, blocking thereon and preventing the rise of the crosspiece towards the roller.

[0014] A drawback of such shutter described in patent EP1975367 is that the cam device is complex to make and install and due to its structural complexity, is easily subject to malfunction which requires the intervention of an expert operator.

[0015] A blocking device for awnings is known from French patent FR2929321 which is substantially similar to that described in the above patent EP1975367 and compared to which has the same drawbacks of structural and functional complexity.

[0016] An awning is known from patent EP1270865, which is provided with a screen blocking device which is susceptible of blocking the awning screen in an extended position.

[0017] Such awning is provided with a frame which comprises a roller on which the awning screen is susceptible of being wound and unwound, two rails on the sides of the roller and extending from the roller along an extension direction and a crosspiece having the ends slidably connected to the rails for sliding along the rails according to the same extension direction. The crosspiece has a prevailing development direction which is transversal to the extension direction of the rails and is fastened to an edge of the screen for guiding the awning screen parallel to the extension direction of the rails.

[0018] In particular, the crosspiece is sliding along the rails in an unwinding direction of the screen according to which the crosspiece moves away from the roller extending the screen between the rails, and in a screen winding direction, according to which the crosspiece approaches the roller on which the screen is rewound.

[0019] Two blocking devices, as described in patent EP1270865, are each susceptible of blocking one of the ends of the crosspiece in a predefined position along the corresponding rail.

[0020] Each of these blocking devices comprises a tab-shaped blocking element having a tip and a base which is fastened to an end of the crosspiece and relative thereto, the blocking tab is oscillating around an axis of oscillation perpendicular to the extension direction of the rails and to the development direction of the crosspiece.

[0021] These blocking devices comprise a spring which elastically retains the blocking element in a resting position, wherein the blocking element projects from the crosspiece within the rail.

[0022] Such blocking element is susceptible of oscillating around its axis of oscillation, in contrast with the elastic reaction of the above spring, between a locking position, wherein the tip of the blocking element faces the screen winding direction, and an unlocking position, wherein the tip of the blocking element faces the screen unwinding direction.

[0023] The subject blocking devices further comprise a stopping block fastened within the rail in a position distal from the roller. The blocking element is susceptible of interfering with such stopping block during the sliding of the crosspiece along the rails and in particular, it is susceptible of engaging, in the locking position, with the blocking element, for preventing the sliding of the crosspiece in the screen winding direction subsequent to an unwinding of the screen which corresponds to the same crosspiece reaching the stopping block along the rail.

[0024] In detail, said stopping block comprises a grapnel portion having a locking seat facing the above screen unwinding direction, in which locking seat the tip of the blocking element is susceptible of jibbing in the locking position.

[0025] Moreover, such stopping block is provided with a base downstream of the locking seat relative to the screen unwinding direction. Such base is susceptible of interfering with the blocking element for keeping it in the locking position or in the unlocking position when the blocking element interferes with the same base.

[0026] Functionally, subsequent to the sliding of the crosspiece along the rails in the screen unwinding direction, the crosspiece reaches the distal zone of the rails where the stopping element is fastened and the blocking element therefore interferes with the stopping block. In detail, starting from the position in which the blocking element comes into contact with the stopping block during the movement of the crosspiece in the screen unwinding direction, the blocking element is rotated by the stopping block up to arranging in the locking position, then it slides on the stopping block going beyond the locking seat and then sliding with the tip thereof on the base of the stopping block. In order to block the crosspiece, it is withdrawn towards the roller for a blocking stroke, after the tip of the blocking element has gone beyond the locking seat but before the same tip has gone beyond the base of the stopping block. Along such blocking stroke, the tip of the blocking element (which is in locking position) slides on the base up to reaching the locking seat in which it jibs, blocking the crosspiece. Subsequent to the jibbing of the tip of the blocking element into the locking seat of the stopping block, the crosspiece cannot slide any further along the rails into the screen winding direction.

[0027] In order to release the crosspiece, starting from the position in which the blocking element is jibbed into the locking seat of the stopping block, the crosspiece is made to slide along the rails in the screen unwinding direction until the blocking element goes beyond the base and, by the spring action, elastically returns to its resting position; then, having reversed the crosspiece motion, it is made to rise along the rails in the screen winding direction.

[0028] In this situation, during the sliding of the crosspiece in the screen winding direction along the rails, when the blocking element reaches the stopping block again, it is elastically rotated by the latter to its unlocking position, in which it is not susceptible of jibbing into the locking seat. The blocking element then slides first on the base and then on the harpoon portion of the stopping block, going beyond it without blocking thereto. The stopping block has the harpoon portion and the base facing the zone comprised between the rails, where the crosspiece slides, so that when the crosspiece is at the stopping block, the blocking element is facing the harpoon portion and the base.

[0029] In other words, the interaction between the blocking element and the stopping block occurs according to a direction parallel to the development direction of the crosspiece. A drawback of this blind described in patent EP1270865 consists in that its blocking device described above is unsteady and little reliable as it is negatively affected by the freedom of movement of the crosspiece in its development direction due to the clearance necessarily provided between the crosspiece and the rails for allowing an easy sliding of the crosspiece along the same rails.

[0030] In fact, in this screen, a movement of the crosspiece along its development direction causes the removal of a first one of the crosspiece ends from the relative rail and at the same time, the approach of the second end to the other rail, so that the blocking element of the first end tends to release from the related stopping block and to loosen the corresponding side of the screen, while the blocking element of the second end tends to rest onto the stopping block, remaining keyed into the locking seat and pushing the second end of the crosspiece in the extension direction of the screen, stretching the related side of the screen.

Disclosure of the invention

[0031] In this situation, therefore, the essential object of the present invention is to eliminate the above-mentioned drawbacks of the prior art solutions by providing a screen roller blind which has the screen that may be blocked in a steady and more reliable manner than the known screen roller blinds or shutters described above.

[0032] Another object of the present finding is to provide a screen roller blind which allows the screen to be easily blocked or released in an extended position.

[0033] A further object of the present finding is to provide a screen roller blind which is inexpensive, safe and operatively totally reliable.

Brief description of the drawings

[0034] The technical features of the finding, according to the above objects, are clearly found in the contents of the claims below and the advantages of the same will appear more clearly from the following detailed description, made with reference to the annexed drawings, which show a purely exemplifying and non-limiting embodiment thereof, wherein:

• figure 1 shows a perspective view of a first embodiment of screen roller blind provided with rails, a crosspiece sliding between the rails and blocking devices adapted to block the crosspiece to the rails, according to the present invention;
• figure 2 shows a perspective view of a detail of the screen roller blind of figure 1 related to one of the blocking devices, with some parts removed to better highlight other ones;
• figure 3 shows a detail of the screen roller blind of figure 1 related to one of the blocking devices in a plan top view;
• figures 4 to 13 show a detail of the screen roller blind of figure 1 related to one of the blocking devices, in a front elevation view, seen in a sequence of operating steps;
• figure 14 shows an exploded perspective view of the detail of figure 3;
• figure 15 shows a perspective view of a detail of a screen roller blind according to a second embodiment of the present invention related to one of the blocking devices;
• figure 16 shows a plan top view of the detail of figure 15;
• figure 17 shows an exploded perspective view of the detail of figure 15;
• figures 18 to 25 show a front elevation view of the detail of the screen roller blind of figure 15, with some parts removed to better highlight other ones and seen in a sequence of operating steps.

Detailed description of a preferred embodiment

[0035] With reference to the accompanying drawings, reference numeral 10 globally indicates a screen roller blind according to the present invention.

[0036] The screen roller blind 10 is preferably intended to be used for adjustably covering the openings of buildings such as windows, doors, skylights and the like, or for covering balconies, porches or other spaces for which a protection against bas weather or the direct sunlight is appreciated.

[0037] Moreover, blind 10 is advantageously intended to adjustably close an opening, such as in particular the opening of a door, a window or the like, obtained on a masonry wall or on another bearing structure of a building, such as for example the openings of a porch, a loggia, a terrace or other similar structures.

[0038] Herein, "blind" is to be understood as any structure provided with a frame which delimits an opening, and with a screen susceptible of at least partly and adjustably intercepting such opening. "Screen" is to be understood as a membrane or a fabric, transparent or opaque, or openwork such as an insect screen or still, a structure with stiff elements connected in a sequence, such as a shutter.

[0039] The screen roller blind 10 is provided with a frame 10a which comprises a roller 11 on which screen 12 is susceptible of being wound and unwound, rails 13 extending from roller 11 along an extension direction A and a crosspiece 14 developing between two ends 14a and 14b thereof along a development direction B substantially perpendicular to the extension direction A of rails 13.

[0040] Crosspiece 14 is fastened to an end edge of screen 12 and has ends 14a and 14b slidably connected to rails 13 along the extension direction A of the same rails 13 to that crosspiece 14, sliding along rails 13, drags screen 12 along with it extending it from roller 11 or withdrawing it towards roller 11.

[0041] In particular, crosspiece 14 is susceptible of selectively sliding along rails 13:

• according to an unwinding direction C of screen 12, in which crosspiece 14 moves away from roller 11 and screen 12 unwinds from roller 11 deploying between rails 13, or
• according to a winding direction D of screen 12, in which crosspiece 14 approaches roller 11 and screen 12 folds onto roller 11 withdrawing along rails 13.

[0042] According to the present invention, the screen roller blind 10 has a specific peculiarity in that it comprises at least one blocking device 100 which comprises a blocking element 15 mechanically connected to an end 14a or 14b of crosspiece 14 and oscillating relative to crosspiece 14 according to an axis of oscillation E substantially parallel to the development direction B of the same crosspiece 14, and at least one stopping block 16 fastened to one of rails 13 and susceptible of being engaged by the blocking element 15 for preventing crosspiece 14 from sliding along rails 13 in the winding direction D.

[0043] In particular, the blocking element 15 is provided with at least one extension 15a elongated in a projecting direction F substantially perpendicular to the development direction B of crosspiece 14. Advantageously, the projecting direction F is radial to the development direction B of crosspiece 14.

[0044] Functionally, the blocking element 15 is susceptible of oscillating, or rotating, around the axis of oscillation E relative to crosspiece 14 so that the projecting direction F, along which extension 15a extends starting from the same axis of oscillation E, rotates along with the blocking element 15.

[0045] In more detail, the blocking element 15 can oscillate around the axis of oscillation E:

• between a locking position in which extension 15a is partially facing towards the winding direction D of screen 12;
• and an unlocking position in which extension 15a is partially facing towards the unwinding direction C of screen 12.

[0046] Extension 15a extends partially facing towards the winding direction D, or the unwinding direction C, when the projecting direction F thereof has a non null component in the winding direction D or in the unwinding direction C, respectively. With reference to the embodiments shown in the annexed figures, the following is shown by way of a non limiting example:

• in figures 5 to 8 and 19 to 21, said locking position, and
• in figures 10 to 13 and 23 to 25, said unlocking position.

[0047] The stopping block 16 is fastened to one of rails 13 and preferably, at least one stopping block 16 is fastened to each of rails 13, with the stopping blocks 16 correspondingly arranged at the same height along the same rails 13 so that they are aligned with each other according to directions parallel to the development direction B of crosspiece 14. In other words, on a pair of rails 13 between which crosspiece 14 slides, there are advantageously fastened at least one pair of stopping blocks 16 with each stopping block 16 of the pair fastened to a corresponding rail 13 in a mirror position relative to the other stopping block 16 fastened to the other rail 13, so that during the operation of the screen roller blind 10, when crosspiece 14 slides along rails 13 and a first end 14a of crosspiece 14 reaches a first stopping block 16 fastened to a first one of rails 13, at the same time the second end 14b of crosspiece 14 reaches the second stopping block 16 fastened to the second one of rails 13.

[0048] In more detail, each stopping block 16 is susceptible of being engaged by a blocking element 15 and comprises, in a sequence along the unwinding direction C of screen 12, a front portion 16a, a locking seat 16b and a rear portion 16c which are susceptible of being engaged in a sequence by the blocking element 15 during the sliding of the latter on the stopping block 16 in the unwinding direction C of screen 12.

[0049] The front portion 16a is susceptible of rotating the blocking element 15 to the locking position and is preferably shaped as a ramp, or is rounded.

[0050] Advantageously, the blocking element 15 is also provided with a front face 15b susceptible of abutting on the front portion 16a of the stopping block 16 and with a rear face 15c susceptible of abutting on the rear portion 16c of the stopping block 16. Functionally, upon the passage of crosspiece 14 at the stopping block 16 along rail 13, the blocking element 15 abuts onto the front portion 16a of the stopping block 16 and slides with a front face 15b thereof on the front portion 16a, which forces a rotation of the blocking element 15 around its axis of oscillation E up to the locking position.

[0051] The locking seat 16b is susceptible of being engaged by extension 15a of the blocking element 15 when it is in the locking position, for preventing the sliding of crosspiece 14 in the winding direction D of screen 12.

[0052] More in detail, preferably, the locking seat 16b is obtained on a joining portion 16d, which joins the front portion 16a and the rear portion 16c of the stopping block 16, and is advantageously defined by a wall of such joining portion 16d facing the unwinding direction C for being engaged by extension 15a when it is partially facing towards the winding direction D, i.e. when the blocking element 15 is in the locking position.

[0053] The rear portion 16c of the stopping block 16 is susceptible of rotating the blocking element 15 in the unlocking position.

[0054] Functionally, upon the passage of crosspiece 14 at the stopping block 16 along rail 13, in the winding direction D, the blocking element 15 abuts on the rear portion 16c and slides with a rear face 15c thereof on the rear portion 16c of the stopping block 16, which forces a rotation of the blocking element 15 around its axis of oscillation E up to the unlocking position.

[0055] According to the present invention, the blocking device 100 further comprises a counter-thrust portion 17 mechanically connected to crosspiece 14 and susceptible of abutting on rail 13 upon the engagement of the blocking element 15 with the stopping block 16, to keep the blocking element 15 interfering with the stopping block 16. Preferably, the blocking device 100 comprises elastic means 18 to oppose the oscillation of the blocking element 15 around the axis of oscillation E starting from a resting position, intermediate between the locking and unlocking positions.

[0056] Said resting position is shown by way of a non limiting example only in figures 4, 9, 18 and 22.

[0057] Operatively, with particular reference to figures 4 to 13 and 18 to 25, crosspiece 14 is susceptible of being made to slide along rails 13 up to reaching and going beyond each stopping block 16 both in the unwinding direction C and in the winding direction D.

[0058] In detail, in order to lock crosspiece 14 along rails 13 at the stopping blocks 16, for example subsequent to a screen unwinding along the rails, crosspiece 14 is made to advance in the unwinding direction C until it reaches a stopping block 16 at which: first, the blocking element 15 with its front face 15b abuts on the front portion 16a of the stopping block 16 and rotates to reach a locking position (as in figures 5 and 19); then, the blocking element 16 slides on the jointing portion 16d (as in figure 6) and goes beyond the locking seat 16b (as in figures 7 and 20).

[0059] At this point, in order to lock the blocking element 15 on the stopping block 16, crosspiece 14 is made to slide in the winding direction D so that extension 15a of the blocking element 15 jibs into the locking seat 16b, as shown for example in figures 8 and 21.

[0060] It should be noted that upon the engagement of extension 15a with the locking seat 16b, the counter-thrust portion 17 is susceptible of abutting on rail 13 (as is shown in figures 8 and 21) for preventing the blocking element 15 from moving away from the stopping block 16 so as to allow the release of extension 15a from the locking seat 16b.

[0061] In order to unlock crosspiece 14, starting from the configuration with extension 15a of the blocking element 15 jibbed into the locking seat 16b of the stopping block 16, it is sufficient to slide crosspiece 14 along rails 13 until extension 15 goes beyond the rear portion 16c of the stopping block 16. When extension 15 goes beyond the rear portion 16c, the blocking element 15 is advantageously rotated by the action of the elastic means 18, in the resting position. Then, sliding crosspiece 14 in the winding direction D, the blocking element 15 slides towards the stopping block 16 and extension 15a engages the rear portion 16c of the same stopping block 16 and rotates in the unlocking position (for example as in figures 10 and 23), then, subsequent to a further sliding of crosspiece 14 in the winding direction D, the blocking element 15 has extension 15a which slides with the rear face 15c on the intermediate portion 16d of the stopping block 16, then goes beyond the locking seat 16b and then goes beyond the front portion 16a of the stopping block 16, thus releasing the stopping block 16. The elastic means 18 preferably return the blocking element 15 to the resting position, for example as shown in figures 4 and 18.

[0062] Functionally, since the blocking element 15 and the stopping block 16 substantially interact in a direction perpendicular to the development direction B of crosspiece 14, a possible sliding of crosspiece 14 relative to rails 13 along the development direction B of the same crosspiece 14 does not interfere with the operation of the blocking device 100.

[0063] In more detail, advantageously, the blocking device 100 comprises a base 19 mechanically fastened to end 14a or 14b of crosspiece 14 and provided with an inner pivoting seat 20. This develops along an axis substantially parallel to the development direction B of crosspiece 14 which defines the axis of oscillation E of the blocking element 15 relative to crosspiece 14.

[0064] Moreover, the blocking device 100 also comprises a pin 21 mechanically fastened to the blocking element 15 and pivotably engaging the pivoting seat 20 rotatably around the axis of oscillation E.

[0065] In particular, pin 21 advantageously has a head 21a integrally fastened to the blocking element 15, for example by means of a screw, and a stem 21b, preferably cylindrical, in the pivoting seat 20 which is also advantageously cylindrical.

[0066] The elastic means 18 advantageously comprise or, according to the embodiments shown in the annexed drawing tables, preferably consist of, a spring which has a first terminal 18a mechanically fastened to pin 21 and a second terminal 18b mechanically fastened to base 19 of the blocking device 100. Said spring is susceptible of elastically opposing any rotation of the blocking element 15 relative to the axis of oscillation E starting from the resting position.

[0067] Advantageously, in said resting position, extension 15a of the blocking element 15, i.e. its projecting direction F, is directed in a direction substantially perpendicular to the extension direction A of rails 13, for example as shown in figures 4, 9, 22 and 18. Preferably, the screen roller blind 10 further comprises retaining means 200 for retaining ends 14a and 14b of crosspiece 14 to rails 13. Such retaining means 200 advantageously define a maximum sliding clearance G of crosspiece 14 with respect to rails 13 along the development direction B of crosspiece 14. Extension 15a of the blocking element 15 and the stopping block 16 have extensions along the development direction B of crosspiece 14 and are positioned relative to each other for allowing the interference for at least a common section T thereof upon the variation of the relative position of crosspiece 14 with respect to the rails in the clearance direction.

[0068] In this way, also subsequent to a sliding of crosspiece 14 relative to rails 13 equal to said maximum sliding clearance, extension 15a of the blocking element 15 and the stopping block 16 are susceptible of interfering, along the extension direction A of rails 13 for engaging and locking crosspiece 14 along the same rails 13.

[0069] With particular reference to figures 1 to 14, according to a first embodiment of the screen roller blind 10, rails 13 comprise or preferably consist of section bars having an inner cavity 22 developing according to the extension direction A of rails 13 and susceptible of being slidably engaged along the extension direction A by the blocking element 15.

[0070] At least one stopping element 16 of the blocking device 100 is fastened to rails 13 preferably in the inner cavity 22 and is at least partially overlapping, according to the extension direction A, extension 15a of the blocking element 15 of the blocking device 100, for interfering with extension 15a.

[0071] More in detail, the screen roller blind 10 according to the above first embodiment of the present invention has rails 13 which comprise two side walls 13a and 13b facing opposite to one another and laterally delimiting the inner cavity 22 of rails 13. Moreover, advantageously, the counter-thrust portion 17 of the blocking device 100 comprises a protrusion 19a of base 19 of the blocking device 100 slidably inserted between the side walls 13a and 13b of rails 13 and susceptible of abutting against a first 13a of the side walls 13a and 13b, the stopping block 16 being fastened to the second 13b of the side walls 13a and 13b.

[0072] In alternative and substantially equivalent embodiments of the present invention, not shown in the annexed figures, the counter-thrust portion may be made with a saddle or a roll susceptible of abutting on rail 13 when the blocking element 15 is jibbed into the stopping block 16.

[0073] According to said first embodiment of the present invention, the retaining means 200, susceptible of retaining ends 14a and 14b of crosspiece 14 to rails 13, advantageously comprise two facing stops 200a and 200b projecting, substantially perpendicular to the development direction B of crosspiece 14, from base 19 of the blocking device 100. These stops 200a and 200b are advantageously spaced from said maximum sliding clearance of crosspiece 14 relative to rails 13.

[0074] Moreover, rails 13 comprise edges 200c slidably inserted between stops 200a and 200b so that the sliding of crosspiece 14 relative to rails 13 along the development direction B of the same crosspiece 14 is limited by the abutment of edges 200c of rails 13 against stops 200a and 200b.

[0075] According to a preferred embodiment of the present invention, the screen roller blind 10 advantageously comprises two blocking devices 100, each of which is susceptible of locking a corresponding end 14a or 14b of crosspiece 14 along a respective one of rails 13.

[0076] Moreover, preferably, each of these blocking devices 100 comprises a plurality of stopping blocks 16 fastened distributed along each one of rails 13 for being susceptible of locking crosspiece 14 in a corresponding plurality of positions along rails 13.

[0077] In more detail, rails 13 preferably comprise an inner lane 13c developing in a direction parallel to the extension direction A. The stopping block 16 advantageously comprises an anchoring portion 23 slidably inserted in the inner lane 13c of rails 13, and fastening means 24 for locking the anchoring portion 23 along the inner lane 13c, for adjusting the position of the stopping blocks 16 along rails 13.

[0078] The inner lane 13c advantageously consists of a longitudinal channel obtained in the rails and provided with a slit 25 which develops longitudinally substantially by the entire length of the inner lane 13c.

[0079] Preferably, the stopping blocks 16 comprise a main body 26 connected to the anchoring portion 23 by means of the fastening means 24 which advantageously consist of screws inserted in a sequence: in holes passing through the main body 26; through slit 25 of the inner lane 13c; and screwed into threaded seats in the anchoring portion 23. Therefore, by tightening or loosening these screws into the anchoring portion it is possible to lock the stopping block 16 to rail 13 or release the sliding thereof along the same rail 13, respectively, for allowing the position of the same stopping block 16 to be adjusted along rail 13 and thus set a position along the same rail 13 in which crosspiece 14 may be locked.

[0080] With particular reference to figures 15 to 25, according to a second embodiment of the present invention, each rail 13 advantageously comprises a rod-shaped element 27 and a support group 28 which is preferably mechanically fastened to the rod-shaped element 27 at an end thereof distal with respect to roller 11.

[0081] The rod-shaped element 27, according to the present second embodiment of the invention, preferably is a stretched cable, but it may be made by a rod or a similar element with prevailing longitudinal development along the extension direction A.

[0082] The support group 28 preferably has a concavity 29 susceptible of receiving in insertion the blocking element 15 of the blocking device 100.

[0083] In particular, such concavity 29 is advantageously delimited by the two facing shoulders 29a and 29b, of which a first one 29a is susceptible of receiving the counter-thrust portion 17 in abutment and on the second one 29b there is fastened the stopping block 16.

[0084] Advantageously, the blocking element 15 is mechanically connected to a sliding seat 30 coupled to the rod-shaped element 27 in a sliding relationship along the extension direction A of rails 13, for guiding the blocking element 15 along rails 13 at least partially overlapping the stopping block 16.

[0085] More in detail, the sliding seat 30 is advantageously obtained through the body of the blocking element 15, as shown by way of a non limiting example in particular in figure 15.

[0086] Moreover, the retaining means 200, susceptible of retaining ends 14a and 14b of crosspiece 14 to rails 13 according to a maximum sliding clearance along the development direction B, according to the present second embodiment of the invention, preferably consist of two edges 30a and 30b of the sliding seat 30 facing in the development direction B of crosspiece 14.

[0087] The distance between edges 30a and 30b defines said maximum sliding clearance of crosspiece 14 relative to rails 13 along the development axis B, which advantageously is at most equal or preferably smaller than the extensions of the stopping block 16 and of extension 15 of the blocking element 15 along the same development axis B, so that extension 15a of the blocking element 15 and the stopping block 16 are susceptible of interfering, along the extension direction A of rails 13, for engaging and locking crosspiece 14 along the same rails 13 also in case of a sliding of crosspiece 14 relative to rails 13 equal to said maximum sliding clearance.

[0088] Preferably, an anti-rotation block 300 is also provided, susceptible of cooperating with the blocking element 15 for preventing the crosspiece from rotating around its development direction B.

[0089] In detail, the anti-rotation block 300 preferably projects from base 19 of the blocking device 100, and is aligned with the blocking element 15 along the extension direction A of rails 13.

[0090] Moreover, the anti-rotation block 300 is provided with a through hole 300a substantially coaxial to the sliding seat 30 of the blocking element 15 and slidably engaged by the rod-shaped element 27.

[0091] It should be noted that the walls of the through hole 300a may cooperate with edges 30a and 30b or replace the latter in defining the maximum sliding clearance of crosspiece 14 relative to the rod-shaped element 27 of rails 13 along the development direction B of the same crosspiece 14.

[0092] According to the present second embodiment, the blocking element 15 is provided with two extensions 15a, preferably substantially symmetrical with respect to said axis of oscillation E so that the blocking element 15 is susceptible of being interchangeably mechanically connected to either ends 14a or 14b of crosspiece 14 and selectively interfering with the stopping block 16 of the blocking device 100 with a first or with the second of these two extensions 15a.

[0093] In other words, having provided the above two extensions 15a, it is possible to produce a single model of blocking device 100, in fact with the blocking element provided with the two extensions 15a which may be fastened to both a first and to the second end of crosspiece 14, to the advantage of the production economy of the screen roller blind 10. Advantageously, the stopping block 16 is provided with slotted holes 31 elongated in the extension direction A of rails 13e engaged by screws 32 engaging threaded seats 33 of the support group 29.

[0094] Such screws 32 may be tightened or loosened with respect to the support group 29 for adjusting the position of the stopping block 16 with respect to the support group 29 along the extension direction of rails 13.

[0095] The finding thus conceived thus achieves the intended purposes.

Claims

1. Screen roller blind (12) provided with a frame (10a) comprising:

- a roller (11) on which said screen (12) can be wound and unwound;

- rails (13) extending from said roller (11) along an extension direction (A);

- a crosspiece (14) developing between two ends (14a, 14b) thereof along a development direction (B) substantially perpendicular to the extension direction (A) of said rails (13), fastened to a end edge of said screen (12) and having said ends (14a, 14b) slidably connected to said rails (13) along the extension direction (A) of said rails (13), said crosspiece (14) being susceptible of selectively sliding along said rails (13) according to an unwinding direction (C) of the screen (12), in which said crosspiece (14) moves away from said roller (11), or according to a winding direction (D) of the screen (12), in which said crosspiece (14) approaches said roller (11),
characterised in that it comprises at least a blocking device (100) comprising:

- a blocking element (15) mechanically connected to an end (14a, 14b) of said crosspiece (14) and provided with at least an extension (15a) elongated in a projecting direction (F) substantially perpendicular to the development direction (B) of said crosspiece (14), said blocking element (15) being able to oscillate with respect to said crosspiece (14), according to an axis of oscillation (E) substantially parallel to the development direction (B) of said crosspiece (14), between a locking position in which said extension (15a) is partially facing towards said winding direction (D) of the screen (12), and an unlocking position in which said extension (15a) is partially facing towards said unwinding direction (C) of the screen (12);

- at least a stopping block (16) fastened to one of said rails (13), susceptible of being engaged by said blocking element (15) and comprising in sequence along said unwinding direction (C) of the screen (12): a front portion (16a) susceptible of rotating said blocking element (15) in said locking position; a locking seat (16b) susceptible of being engaged by the extension (15a) of said blocking element (15) in said locking position, to prevent said crosspiece (14) from sliding in said winding direction (D) of the screen (12); a rear portion (16c) susceptible of rotating said blocking element (15) in said unlocking position;

- a counter-thrust portion (17) mechanically connected to said crosspiece (14) and susceptible of abutting on said guide, upon the engagement of said blocking element (15) with said stopping block (16), to keep said blocking element (15) interfering with said stopping block (16).

2. Screen roller blind (12) according to claim 1, characterised in that said blocking device (100) comprises elastic means (18) to oppose the oscillation of said blocking element (15) around said axis of oscillation (E) starting from a resting position, intermediate between said locking and unlocking positions.

3. Screen roller blind (12) according to any one of the previous claims, characterised in that said blocking device (100) comprises:

- a base (19) mechanically fastened to the end (14a, 14b) of said crosspiece (14) and provided with an inner pivoting seat (20) developing along an axis substantially parallel to the development direction (B) of said crosspiece (14), which defines the axis of oscillation (E) of said blocking element (15);

- a pin (21) which is mechanically fastened to said blocking element (15) and pivotably engages said pivoting seat (20) around said axis of oscillation (E).

4. Screen roller blind (12) according to claims 2 and 3, characterised in that said elastic means (18) comprise a spring having a first terminal (18a) mechanically fastened to said pin (21) and a second terminal (18b) mechanically fastened to the base (19) of said blocking device (100), said spring being susceptible of elastically opposing a rotation of said blocking element (15) relative to said axis of oscillation (E) from said resting position.

5. Screen roller blind (12) according to any one of the previous claims, characterised in that in said resting position the extension (15a) of said blocking element (15) is facing towards a direction substantially perpendicular to the extension direction (A) of said rails (13).

6. Screen roller blind (12) according to any one of the previous claims, characterised in that it comprises retaining means (200) to retain the ends (14a, 14b) of said crosspiece (14) to said rails (13) defining a maximum sliding clearance (G) of said crosspiece (14) with respect to said rails (13) along the development direction (B) of said crosspiece (14); the extension (15a) of the blocking element (15) and the stopping block (16) being susceptible of interfering for at least a common section (T) thereof upon the variation of the relative position of the crosspiece (14) with respect to the rails in the clearance (G) direction.

7. Screen roller blind (12) according to any one of the previous claims, characterised in that said rails (13) comprise section bars having an inner cavity (22) developing along the extension direction (A) of said rails (13) and susceptible of being slidably engaged along said extension direction (A) by said blocking element (15), at least one stopping block (16) of said blocking device (100) being fastened to said rails (13) in said inner cavity (22) and said stopping block (16) at least partially overlapping, according to said extension direction (A), the extension (15a) of the blocking element (15) of said blocking device (100), for interfering with said extension (15a).

8. Screen roller blind (12) according to claim 7, characterised in that:

- said rails (13) comprise two side walls (13a, 13b) facing opposite to one another and laterally delimiting the inner cavity (22) of said rails (13); and in that

- the counter-thrust portion (17) of said blocking device (100) comprises a protrusion (19a) of the base (19) of said blocking device (100) slidably inserted between the side walls (13a, 13b) of said rails (13) and susceptible of abutting against a first of said walls, the stopping block (16) of said blocking device (100) being fastened to the second of said side walls (13a, 13b).

9. Screen roller blind (12) according to any one of the previous claims, characterised in that it comprises two of said blocking devices (100) each of which is susceptible of blocking a corresponding end (14a, 14b) of said crosspiece (14) along a respective rail of said rails (13) and provided with one or more of said stopping blocks (16) distributed along each of said rails (13) to be susceptible of blocking said crosspiece (14) in a corresponding plurality of positions along said rails (13).

10. Screen roller blind (12) according to any one of claims from 7 to 9, characterised in that said rails (13) each comprise an inner lane (13c) developing in a direction parallel to said extension direction (A), said stopping block (16) comprising:

- an anchoring portion (23) inserted in said inner lane (13c) of one of said rails (13) and susceptible of sliding in said inner lane (13c);

- fastening means (24) to block said anchoring portion (23) along said inner lane (13c) to adjust the position of said stopping blocks (16) along said rails (13).

11. Screen roller blind (12) according to any one of claims from 1 to 6, characterised in that each of said rails (13) comprises a rod-shaped element (27) and a support group (28) having a concavity (29) susceptible of receiving by insertion the blocking element (15) of said blocking device (100) and laterally delimited by two shoulders (29a, 29b) facing opposite to one another of which a first being susceptible of receiving in abutment said counter-thrust portion (17) and a second on which said stopping block (16) is fastened, said blocking element (15) being mechanically connected to a sliding seat (30) coupled to said rod-shaped element (27) in a sliding relationship along the extension direction (A) of said rails (13), to guide said blocking element (15) along said rails (13) at least partially overlapping said stopping block (16).

12. Screen roller blind (12) according to claim 11, characterised in that said rod-shaped element (27) is a tensioned rope.

13. Screen roller blind (12) according to any one of claims 11 and 12, characterised in that said sliding seat (30) is obtained passing through the body of said blocking element (15).

14. Screen roller blind (12) according to any one of claims from 11 to 13, characterised in that said blocking element (15) is provided with two extensions of said extension (15a) substantially symmetrical with respect to said axis of oscillation (E) so that said blocking element (15) is susceptible of being interchangeably mechanically connected to either ends (14a, 14b) of said crosspiece (14) and selectively interfering with the stopping block (16) of said blocking device (100) with a first or with the second of said two extensions.

15. Screen roller blind (12) according to any one of claims from 11 to 14, characterised in that said support group (28) is mechanically fastened to said rod-shaped element (27) at an end of this latter distal with respect to said roller (11).

Drawing