DUAL SCREENING DEVICE FOR A WINDOW

Abstract: A dual window screening device comprises a first screening element (1) with a breadth of flexible screening material, which in the end is rolled up on a roller tube (2) at one of a pair of sash members positioned opposite each other (4), whereas the opposite end is connected with an end rail profile (5). A second screening element (8) is in one end fastened to the opposite sash member (9) and in the opposite end connected with an end rail profile (10). The screening device may be designed for manual or electronic operation and comprises guiding and arresting means permitting mutually independent adjustment of the two screening elements (1, 8) in arbitrary positions. The guiding and arresting means comprise a common guide track (11) for the screening elements so that these are used in a common guiding plane.

Description: Dual screening device for a window The invention relates to a screening device for a window with a substantially rectangular sash having two pairs of sash members positioned opposite each other and of the type comprising a first screening element with a breadth of a flexible screening material which in one end is rolled up on a roller tube fastened to one sash member in the first pair of sash members, and a second screening element which in one end is fastened to the second sash member in said first pair, where in connection with the other pair of sash members, guiding means are provided for guiding the movement of the two screening elements, whereas both screening elements in the opposite end are connected with an end rail profile. It is well known to provide windows with screening devices both for light dimming in the form of actual blackout as well as dimming of penetrating sun light in daylight hours, and for screening against insects. In light-dimming screening devices to be positioned close to the window sash, it is, however, with the known devices not possible at one time to take more light- dimming purposes into account, eg. to provide a window with both a siesta roller blind and a Venetian blind or a translucent pleated blind which may especially be desirable for roof windows in an oblique roof surface where the light incidence is considerably larger than in vertical windows. DE Publication no 2934122 discloses a screening device of the above type in which a translucent and air permeable curtain at its upper end is connected with a carrying tube for connection with the lower end of a roller shutter. The screening device is operated in the way that by means of engagement means the curtain is coupled with the roller shutter and subsequently pulled out of its normally rolled up position to a desired placement in the elevation of the window. This arrange¬ ment, however, implies that the curtain may only be used together with the roller shutter which partly results in demands being made to the design and function of the engagement means and partly rules out the possibilities of optional screening combinations as the area of the window opening which is not covered by the roller shutter is either covered completely - by a coupled curtain - or not at all. Since the roller shutter and the curtain are guided in planes which are displaced in a mutually parallel manner, this known device is furthermore relatively bulky and requires side guides with separate tracks for the roller shutter and the curtain, respec¬ tively. According to the invention these drawbacks are eliminated in a simple way in that the guiding means at each sash member in said other pair comprise a side guide rail with a common track for the two screening elements, that arresting means are provided for mutually inde- pendent retention of the screening elements in a number of arbitrary positions, and that the mutually facing sides of the two end rail profiles are designed so that they may enter into a mutually form-adapted abutment. By this design it is obtained that the two screening elements move in a common guiding plane and may be parked individually and fully independently in arbitrary inter¬ mediate positions such that the parts belonging to the roof light-admitting area of the window and covered by the screening elements may be adjusted correspondingly. The screening device may be designed for manual operation in the way that the end rail profiles of the two screening elements for individual manual operation are connected each with a catching device, and that said side guide rail and end rail profiles are designed with cooperating friction arresting means for said mutually independent retention of the screening elements against an impact of force directed against the sash member to which the screening element in question is fastened. The screening device may according to a further development of the invention also be designed for electrical operation in the way that the two screening elements are electrically operated, said end rail profile of each element being connected with a separate electric drive motor through a flexible connection device which provides said arresting means in which control circuits for the two drive motors are arranged for deactivating an activated drive motor when the end rail profiles enter into mutual abutment. The invention will be explained in more detail with reference to the schematical drawing in which Fig. 1 in perspective shows an embodiment of a roof window with a dual screening device according to the invention, Figs. 2 and 3 show sectional views of the screening device in two different positions, and Fig. 4 shows a sectional view of the guiding and arresting means to be used by manual operation of the screening device. In the shown embodiment the dual screening device for a roof window with a sash consisting of horizontal sash members 4 and 9 and vertical sash members 16 and 17 comprises a roller blind 1 which is rolled up on a spring-biassed roller tube 2 mounted in a casing 3 which here as shown is fastened to the horizontal top section 4 of the window sash, whereas an end rail profile in the form of a bottom rail 5 is fastened at the free end of the roller blind. In order to secure the roller blind 1 in unrolled positions against the spring bias whose function is to keep the curtain cloth in a permanently tight stretch, guiding and arresting means are provided at the side sections of the sash, in the shown example in the form of side guiding rails 6 and 7 with a track 11, by which a friction end pin 12 may as shown in Fig. 4 by appropriate friction secure the roller blind in arbitrary unrolled positions. The second screening element is in the shown embodiment constituted by a sunlight dimming, but translucent pleated blind 8, whose lower end is as shown fastened to the horizontal bottom section 9 of the window sash, whereas the free upper end is connected with an end guiding rail 10 guided by means of friction end pins 12 in connection with the rail 10 in the same track 11 in the guiding rails 6 and 7 as the roller blind 1, so that the pleated blind 8 may also be secured against the gravitational force in arbitrary unrolled positions, independently of the roller blind 1 being retained. As shown in Figs. 2 and 3, the end rail profiles 5 and 10 are on their mutually facing sides designed to enter into a mutually form-adapted abutment, a bottom sealing 13 on the rail 5 being designed with an arc- shaped underside matching the top side of a rearwards projecting flange part 14 on the rail 10. The dual screening device may also be designed in an inverse manner with a pleated blind above and a roller blind below. Furthermore, the two screening elements may be fastened to the vertical sash members in the sash of the window so that they move sideways. In the shown embodiment, the screening device is designed for manual operation, both end rail profiles 5 and 10 being designed with a catching device, eg. as shown in Figs. 2 and 3 in the form of a continuous catching track 15. However, the dual screening device may, as mentio- ned, alternatively be designed for manual operation. Thus, for each of the screening elements 1 and 8 the accompanying profile 5 and 10, respectively, may through a cord drive of a design known per se eg. as known from the EP patent 015,043 be connected with a separate electric drive motor which, both for the roller blind 1 and for the pleated blind 8, may be positioned either in the casing 3 with the roller tube in or at the sash bottom section 9. As to operation and wiring, it is an advantage if the two drive motors are positioned in or at the same sash member. To avoid malfunction, the control circuits for the two drive motors may in a known manner be connected with spring-biassed cord tension sensors which detect the cord tension in the two cord drives and switch off an ac¬ tivated drive motor when the cord slackens as a result of the profiles 5 and 10 entering into a mutual abutment.

Claims: C A I M S 1. A screening device for a window with a substantially rectangular sash having two pairs of sash members positioned opposite each other (4, 9;16, 17) and of the type comprising a first screening element (1) with a breadth of a flexible screening material which in one end is rolled up on a roller tube (2) fastened to one sash member (4) in the first pair of sash members, and a second screening element (8) which in one end is fastened to the second sash member (9) in said first pair, where in connection with the other pair of sash members, guiding means are provided for guiding the movement of the two screening elements, whereas both screening elements in the opposite end are connected with an end rail profile (5,10) , characterized in that the guiding means at each sash member in said other pair comprise a side guide rail (6,7) with a common track (11) for the two screening elements, that arresting means are provided for mutually independent retention of the screening elements (1,8) in a number of arbitrary positions, and that the mutually facing sides (13,14) of the two end rail profiles (5,10) are designed so that they may enter into a mutually form-adapted abutment. 2. A window screening device according to claim 1, characterized in that the first screening element has the form of siesta roller blind (1) rolled up with spring bias on said roller tube (2) , whereas the further scree¬ ning element (8) is a translucent element. 3. A window screening device according to claim 1 or 2, characterized in that the end rail profiles (5-10) of the two screening elements for individual manual operation are connected each with a catching device (15) , and that said side guide rail (6,7) and end rail profiles (5,10) are designed with cooperating friction arresting means (11,12) for said mutually independent retention of the screening elements (1,8) against a load directed towards the sash member to which the screening element in question is fastened. 4. A window screening device according to claim 1 or 2, characterized that the two screening elements (1,8) are electrically operated, said end rail profile (5,10) of each element being connected with a separate electric drive motor through a flexible connection device which provides said arresting means in which control circuits of the two drive motors are arranged for deactivating an activated drive motor when the end rail profiles (5,10) enter into mutual abutment. 5. A window screening device according to claim 4, characterized in that said flexible connection device is constituted by a cord drive, and that said control circuit for each electric drive motor is meant to be affected by a cord tension sensor.

Inventors: NIELSEN TORBEN HOLST, NIELSEN, TORBEN, HOLST
Applicants: RASMUSSEN KANN IND AS, V. KANN RASMUSSEN INDUSTRI A/S
Application year: 1996
Main classification: E06B9
IPC codes: E06B9