A SCREENING ARRANGEMENT WITH SIDE RAILS, AND A METHOD OF MANUFACTURING SUCH A SIDE RAIL

Abstract

 The screening arrangement comprises a bottom element (4) and two side rails (10). The bottom element (4) is movable with respect to the two side rails (10) between a non-screening position and a screening position by means of a drive means comprising a first transmission means (30) arranged in the bottom element (4), and a second transmission means (20) arranged in each of the two side rails (10) such as to extend substantially in the longitudinal direction of the side rail (10). Each side rail (10) comprises a first flange (11) extending substantially in the width direction (W), a second flange (12) extending substantially in parallel with the first flange (11), in the width direction (W), and positioned to cover at least a part of the bottom element (4), and a third flange (13) connecting the first and second flanges (11, 12) and extending substantially in the depth direction (D). The second transmission means (20) is formed integrally in at least one of said flanges (11, 12, 13) of said side rail (10), and that said side rail (10) is of an extrudable material.

Description

Field of the invention

[0001] The present invention relates to a screening arrangement for a window, preferably a roof window, comprising a frame with a top member, a bottom member and two side members, the screening arrangement comprising: at least one bottom element, and two side rails defining a longitudinal direction, a width direction and a depth direction, the at least one bottom element being movable with respect to the two side rails between a non-screening position and a screening position by means of a drive means comprising a first transmission means comprising a circular gear including at least one pinion arranged in said at least one bottom element, and a second transmission means comprising at least one rack of teeth arranged in each of the two side rails such as to extend substantially in the longitudinal direction of the side rail, to engage with the at least one pinion of the first transmission means, each side rail comprising a first flange extending substantially in the width direction, a second flange extending substantially in parallel with the first flange, in the width direction, and positioned to cover at least a part of the bottom element, and a third flange connecting the first and second flanges and extending substantially in the depth direction. The invention furthermore relates to a method of manufacturing a side rail of a screening arrangement.

Background art

[0002] Screening arrangements including screening devices in the form of blinds are traditionally used for screening an aperture of a building structure, most often the light-admitting aperture of windows, but also of doors and other building openings. The blinds are either installed to extend substantially vertically in a building façade, or in an obliquely positioned roof window installed in an inclined surface, or as a horizontally extending cover for openings in a horizontal surface. When not screening the aperture, the screening body is normally rolled or folded up and gathered at a top element of the screening arrangement.

[0003] Examples of prior art screening arrangements include Applicant's European patents EP2738342 B1, EP2738343 B1 and EP2738344 B1. In turn, the operational principles of such screening arrangements are based on well-proven techniques known for instance from GB 668669, US 8,881,790 B2 and DE 202007018180 U1.

[0004] The side rails of such screening arrangements thus function partly as guiding means for guiding the bottom element and side edges of the screening body of the screening arrangement during operation, partly additional darkening in the case of black-out blinds. Furthermore, the side rails function to cover drive means which in some applications include cord systems and pulleys. Eventually, the side rails need to provide an aesthetically pleasing transition between the screening arrangement and the surrounding building structure, typically an inner wall.

[0005] In many internal screening arrangements, facing the interior of the room of the building in which the window is installed, it is a typical requirement that the side rails are slender and of a thin-walled material. Since a number of functionalities are necessarily included in the side rails, which at the same time must fulfil certain requirements to appearance, the available space is unavoidably limited.

[0006] The complexity of the side rails furthermore requires special precautions during manufacture, which may render the production costs expensive.

Summary of the invention

[0007] With this background it is an object of the present invention to provide a screening arrangement of the kind mentioned in the introduction which may be used within a wide range of fields, in particular where space constraints are present, and which at the same time provides for optimum conditions for the operability of the screening arrangement, and while being cost-effective to manufacture.

[0008] In a first aspect, this and further objects are met by the provision of a a screening arrangement which is characterised in that said rack of teeth of the second transmission means is formed integrally in at least one of said flanges of said side rail, the teeth of said rack having a base portion provided at the at least one flange, a head portion engaging the at least one pinion of the first transmission means, and a body portion extending between the base portion and the head portion, that said side rail is of an extrudable material, and that the head portion of the rack of teeth is wider, i.e. has a larger extent in the width direction, than at least the part of the body portion of the rack which is adjacent to the head portion.

[0009] By the provision of the rack of teeth of the second transmission means as an integral part of, i.e. in one piece with, the side rail itself, the drive means is rendered substantially more compact while at the same time providing the required operational conditions. Forming the second transmission means in one or more of the flanges already present in the side rail, an optimum balance is found in that the side rail is easily mounted on the frame of the window, whereas it is at the same time possible to choose the location of the second transmission means in a flexible way. By forming the head portion of the rack of teeth wider than the body portion, a compromise has been found between the desire to form the rack of teeth as narrow as possible in the width direction on one hand and the need for a reliable engagement between the first and second transmission means on the other. Hence, the rack-and-pinion transmission may be formed in an optimum manner by a careful choice of dimensions of the portions of the rack of teeth. As the material of the side rails is extrudable, a simple and cost-effective manner of providing the side rail with an integrated rack of teeth is made possible by extrusion.

[0010] The term "extrudable material" should be interpreted to incorporate any material that is able to be formed by forcing a blank of material through a die of a desired cross-section. Typical extrudable materials include metallic and plastic materials, but also composite, ceramic and fiber materials are conceivable.

[0011] It is noted that the term "drive means" should be interpreted in its broadest sense, encompassing all kinds of force and movement transmission between the first transmission means and the second transmission means. Thus, in the case of an electrically operated screening arrangement, the first transmission means transmits a driving force to the second transmission means whereby the bottom element is moved. Conversely, in a manually operated screening arrangement, the driving force is provided by the user pushing or pulling the bottom element whereby the interaction between the first and second transmission means provides guidance and synchronicity such that the ends of the bottom element move at the same pace. In this way, the bottom element is kept parallel to the top and bottom members of the frame at all times, thereby avoiding skew positions that could hamper proper functioning. Thus, also in electrically operated screening arrangement, only one end of the bottom element needs to be provided with driven first transmission means whereas the first transmission means at the other end acts as a follower.

[0012] The shape and relative dimensions of the head portion of the rack of teeth may be chosen to fit the required specifications and in dependence on the choice of material, both of the side rail with the integrated rack of teeth and of the pinion. Furthermore, the formation of the teeth of the rack or racks may in principle be carried out in any suitable manner. In one presently preferred embodiment, the at least one rack of teeth is formed by extrusion and at least one subsequent rack forming operation, where the head portion is preferably provided with a larger extent in the width direction during the subsequent rack forming operation.

[0013] In a second aspect, a method of manufacturing a side rail of a screening arrangement is provided.

[0014] Advantages of the first aspect as described herein apply to the second aspect and vice versa.

[0015] Other presently preferred embodiments and further advantages will be apparent from the following detailed description and the dependent claims.

Brief description of drawings

[0016] The invention will be described in more detail below by means of nonlimiting examples of embodiments and with reference to the schematic drawing, in which

Fig. 1 is a perspective view of a prior art screening arrangement mounted in a roof window;

Fig. 2 is a partial perspective view of details including a side rail and a bottom element of a screening arrangement in a first embodiment of the invention;

Fig. 3 shows an end view of the details of Fig. 2, on a larger scale;

Fig. 4 shows an end view of the side rail of the screening arrangement of Fig. 3;

Figs 5a to 5h each shows an end view corresponding to Fig. 4 of the side rail of further embodiments of the screening arrangement according to the invention;

Fig. 6 is a perspective view of a detail of a screening arrangement in a still further embodiment of the invention;

Fig. 7 shows an end view corresponding to Fig. 3, of the still further embodiment of the invention;

Fig. 8 shows an end view of the detail of Figs 6 and 7;

Figs 9a and 9b are partial plan views of the side rail of the screening arrangements in the first and the still further embodiment, respectively, of the invention;

Figs 10a and 10b are partial plan views of the side rail and bottom element in the first and the still further embodiment, respectively, of the invention;

Fig. 11 shows an end view of the bottom element of the screening arrangement in an embodiment of the invention;

Figs 12a to 12d each shows an end view corresponding to Fig. 4 of the side rail of still yet further embodiments of the screening arrangement according to the invention; and

Figs 13 to 15 are flow charts for respective embodiments of methods for forming a rack in a side rail.

Detailed description of the invention

[0017] Fig. 1 shows a prior art screening arrangement 3'installed in a window generally designated 1, here represented by a frame 2 which is an openable sash adapted to be mounted in a stationary frame (not shown), for instance to be installed in an inclined roof surface. It is noted that the terms "sash" or "frame" are to be understood as incorporating any substantially rectangular structure positioned in any opening in a building, whether in a wall or the roof, and surrounding an aperture to be screened. As is well-known, the frame 2 thus has four frame members: a top member, a bottom member and two side members. In the shown version of the window, the frame 2 is thus a glass-carrying sash encasing a pane 5 in the opening formed by the frame members. Such a prior art screening arrangement is shown and described in for instance Applicant's European patent EP2150671 B1.

[0018] The prior art screening arrangement 3' defines, in the condition of use in which it is mounted in the frame 2, a screening plane substantially parallel to a plane defined the longitudinal extensions of the top and bottom members of the frame on one hand and the longitudinal direction of the side members on the other. The terms "left-hand" and "right-hand" refer to the orientation shown in for instance Fig. 1, and are utilized for reasons of convenience only. Similarly, the terms "front" and "back" are utilized to denote the sides of the screening arrangement 3', "front" being the side intended to face inwards into the interior of a building, and "back" the outwards facing side. The terms "upper" and "lower" refer to the orientation of the screening arrangement installed in a frame, where "upper" refers to the top member of the frame and "lower" refers to the bottom member of the frame.

[0019] The prior art screening arrangement 3' has a bottom element 4' connected to a screening body (not shown) which extends in the screening plane and covers the opening of the frame in its screening positions, whereas it is placed in its non-screening position at the top member of the frame 2 in Fig. 1. The side edges of the screening body and the longitudinal ends of the bottom element 4' are guided in side rails 10' connected to the side members of the frame 2. In the prior art screening arrangement, the side rails 10' are mitred at one end and connected to a top rail. The orientation and terms used to describe the screening arrangement in the present context are for convenience and ease of understanding; hence, the bottom element could thus be provided in parallel with "side" members instead, depending on the specific orientation in the mounted condition.

[0020] In the following, a screening arrangement in a first embodiment of the invention will be described with particular reference to Figs 2 to 4. As in the prior art, the screening arrangement 3 comprises a bottom element 4 (cf. Fig. 4) and two side rails 10 of which one is shown. It is to be understood that more than one bottom element 4 may be present in the case of more than one screening device is present, and the term bottom element is also intended to cover any movable profile or bar element fulfilling the function. It is also to be understood that although only one side rail 10 is shown, the other side rail to be positioned at the opposite side member may be formed in the same manner, mirror inverted, or be of a varied design.

[0021] It is noted that elements having the same or analogous function throughout the embodiments are denoted by the same reference numerals.

[0022] In Fig. 2, the side rail 10 is seen from the back side of the screening arrangement and defines a longitudinal direction L, a width direction W and a depth direction D.

[0023] The bottom element 4 is movable with respect to the two side rails 10 between a non-screening position and a screening position by means of a drive means comprising a first transmission means generally designated 30 arranged in the bottom element 4, and a second transmission means generally designated 20 arranged in each of the two side rails 10 such as to extend substantially in the longitudinal direction L of the side rail 10.

[0024] As will be described in further detail below, the second transmission means 20 is formed integrally in said side rail 10, and the side rail 10 is of a metallic material.

[0025] In the first embodiment of Figs 2 to 4, the side rail 10 comprises a first flange 11 extending substantially in the width direction W, a second flange 12 extending substantially in the width direction W and positioned to cover at least a part of the bottom element 4, and a third flange 13 connecting the first and second flanges 11, 12 and extending substantially in the depth direction D. The second flange 12 faces the interior of the room and thus forms a front surface of the side rail 10 in the mounted condition of the screening arrangement.

[0026] Specifically, the third flange 13 of this embodiment has an extended portion 14 extending from the first flange 11 in the depth direction D away from the second flange 12.

[0027] Fastening means, such as openings for the reception of screws or the like, or snap engagement means are present in the side rail 10 to allow connection to the respective side member of the frame of the window. The fastening means are typically provided in the third flange 13, and/or in the specific embodiment, in the extended portion 14 of the third flange 13.

[0028] In the embodiment shown, the side rail 10 is provided with further flanges including a fourth flange 15 at the end of the first flange 11 opposite its connection to the third flange 13. Here, the fourth flange 15 has an extended portion 16 forming together with a fifth flange 18 provided on the second flange 12 an opening extending throughout the longitudinal direction L of the side rail 10 to receive a side edge of the screening body.

[0029] The fifth flange 18 also forms a track together with a sixth flange 19a protruding from the third flange 13. This track serves to receive an angular bracket to form a mitred connection with a top rail as mentioned in the above description of the prior art screening arrangement.

[0030] Finally, as indicated in Fig. 3 only, the side rail 10 may be provided with a seventh flange 19b located opposite the above-mentioned opening between the extended portion 16 of the fourth flange 15 and the fifth flange 18. The seventh flange 19b functions as an end stop for the side edges of the screening body and guide elements (not shown) at the ends of the bottom element 4. This ensures that the screening body and the bottom element 4 are kept in position, and in turn secures the engagement between the first and second transmission means. Such an end stop, or end guide, could alternatively or additionally be provided in any other suitable manner; for instance by meshing gears etc. One example of a guide is for instance given in Applicant's published European patent application EP 2 476 858 A2.

[0031] In general, the second transmission means 20 could be formed in any flange of the side rail 10 to obtain maximum flexibility as regards the position.

[0032] In particular, the transmission means may be placed in one of the first, second and third flanges 11, 12, and 13. It is also conceivable to form second transmission means 20 in more than one flange.

[0033] In the shown first embodiment, the second transmission means 20 is formed in one flange only, and in particular as here in the first flange 11.

[0034] In a not-shown alternative embodiment, the second transmission means is formed in the second flange 12. A further alternative embodiment showing the position in the third flange 13 is shown in Fig. 12a. In the cases in which the side rail 10 comprises the fourth flange 15, the transmission means 20 may alternatively be formed in the fourth flange 15 as shown in Fig. 12c.

[0035] In the presently preferred embodiment the second transmission means of the side rail 10 of the screening arrangement 3 comprises at least one rack of teeth 20 to engage with the first transmission means 30 of the bottom element 4.

[0036] The rack 20 is thus formed integrally in the side rail 10. In the specific form of the side rail 10 shown, the rack 20 is formed in the first flange 11 to protrude in the depth direction D, away from the second flange 12. The formation of the rack 20 facing outwards as in Figs 2 to 4 is of particular advantage in roof windows which are traditionally installed in an inclined position. Hence, gravity will ensure a safe engagement between the first transmission means 30 and the second transmission means, here in the form of rack 20. An alternative position, although not preferred, is shown in Fig. 12b.

[0037] By the term "integrally in" as used in the present context, it should be understood that this term incorporates forming the rack of teeth as an integral structure protruding from the actual flange of the side rail. The rack of teeth may thus be said to form a rack flange protruding from the side rail flange, and in which the teeth are formed, thus rendering the rack flange including its teeth as a comb-like structure.

[0038] The profiling of the rack of teeth 20 of the second transmission means is chosen to fit the requirements to the screening arrangement in question. Generally, the teeth of the rack 20 have a base portion 23 provided at the first flange 11, a head portion 21 engaging the first transmission means 30, and a body portion 22 extending between the base portion 23 and the head portion 21.

[0039] It is preferred, as shown in Fig. 4, that the head portion 21 of the rack of teeth 20 is wider, i.e. has a larger extent in the width direction W, than at least the part of the body portion 22 of the rack which is adjacent to the head portion 21. The difference in width between the head portion 21 and the body portion 22 is advantageous in that a more secure engagement between the first transmission means 30 and the second transmission means, here in the form of rack 20, is ensured. Typical values of the ratio between the width of the head portion 21 and the width of the body portion 22 at the part adjacent to the head portion include a range of at least 1.05:1: preferably at least 1.2:1, and more preferably at least 2:1.

[0040] The shape of the head portion 21 of the rack of teeth 20 may in principle be formed in any suitable manner as long as it may be warranted from a manufacture point of view. In the first embodiment of Figs 2 to 4, the head portion 21 is substantially bud-shaped. Alternative shapes may advantageously be selected from the group comprising: substantially circular, anvil-shaped, and T-shaped. Examples of such alternative shapes are shown in Figs 5f, Fig. 5e and Fig. 5g, respectively.

[0041] It is noted that depending on the choice of manufacturing of the side rail, the head portion 21 may be formed wider than the body portion 22 already during the initial forming step, typically during extrusion, or the head portion 21 and the body portion 22 may be formed with similar width and the head portion 21 made wider during a subsequent step.

[0042] It is preferred that the rack of teeth 20 is formed by extrusion and one or more subsequent rack forming operations. During such a subsequent rack forming operation, the head portion may be provided with a wider extent. This applies both when the side rail is extruded with a rack flange as a precursor to the rack of teeth in which the head portion already has a larger width than the body portion and/or the base portion, and when the side rail following extrusion is provided with a shape of the rack flange to form the rack of teeth 20, as shown for instance in Figs 5a-5d and 5h.

[0043] Alternative shapes of the teeth of the rack 20 including the head portion 21 and entire body portion 22 are also conceivable. For instance, the teeth of the rack 20 may be curved (not shown). In such a curved configuration, it is possible to provide the screening arrangement with an outwards directed force acting to keep the first and second transmission means in mutual engagement and at the same time ensure that the screening body is kept tight.

[0044] A tapered shape in the depth direction D is also conceivable, preferably also including the body portion 22 (Figs 5c and 5d). Furthermore, the teeth of the rack 20 may be substantially straight, optionally perpendicular to the sides of the head portion 21 (Figs 5a, 5b and 5h).

[0045] One further aspect to the formation of the side rail 10 with integral second transmission means 20 is the strength and mechanical properties such as bending resistance. This applies to the side rail in general and in the above embodiments to the flange in which the rack of teeth 20 is formed in particular. Hence, a support portion 17 may be present opposite the base portion 23.

[0046] In order to ensure proper meshing of the gear, the ratio between the width, i.e. the dimension in the width direction W, of the head portion and the height, i.e. the dimension in the depth direction D, of the rack, from the base portion to the head portion, is up to 1:3, preferably up to 1:4.

[0047] Specific values of the components involved may in principle be chosen relatively freely. However, typical approximate values of individual measures are given in the following:

the total width of the side rail 10, in the width dimension W: 30 mm;

the total depth of the side rail, in the depth direction D: 33 mm;

width of first flange 11, in the width dimension W: 22 mm;

length of second flange 12, in the width dimension W: 33 mm;

width of head portion 21: 1.3 mm;

width of body portion 22: 1.0 mm;

height of rack 20, in the depth direction D: 5 mm;

height of head portion 21: 1.2 mm;

height of body portion 22: 3.8 mm.

[0048] In an alternative embodiment shown with reference to Figs 6 to 8, it is seen that two parallel racks 20a, 20b are formed integrally in the same flange 11. Further racks may be provided in the same flange, or a further rack may be provided in another flange than the first.

[0049] In the embodiment shown in which two parallel racks of teeth 20a, 20b are provided to engage with one pinion 31, the pinion 31 is provided with such a width that the pinion 3 extends across and is configured to mesh with at least a part of each of the two parallel racks of teeth 20a, 20b. More specific, the pinion 31 shown in Fig. 7 has a width to substantially cover the racks of teeth 20a, 20b.

[0050] In an alternative not-shown embodiment, two parallel racks of teeth 20a, 20b are provided as in Fig. 7, and the first transmission means comprising a circular gear includes two pinions, which are configured to mesh with a respective rack of teeth 20a, 20b. Such pinions have a smaller width than the pinion 31 shown in Fig. 7. The width of the two pinions may be identical or different from each other.

[0051] In a further, not-shown embodiment the screening arrangement is provided with two racks of teeth 20a, 20b to engage with at least one pinion 31. The screening arrangement comprises two side rails 10, each including first, second and third flanges 11, 12, 13, and at least one bottom element 4 which is movable with respect to the side rails 10 by means of a drive means comprising first transmission means comprising a circular gear including the pinion 31 or pinions, arranged in the bottom element and second transmission means including the two racks of teeth formed integrally in the same flange of the side rail. The pinion 31 is provided with such a width that it extends across and is configured to mesh with at least a part of each of the two parallel racks of teeth 20a, 20b. The provision of two racks of teeth 20a, 20b entails that a stable engagement between the first and second transmission means is obtained, regardless of the profiling of the racks of teeth. In further developments of this not-shown embodiments, the head portion of the respective rack of teeth may be made wider than at least the portion of the body portion adjacent to the head portion.

[0052] Regardless of the design of the second transmission means 20 as described in the above embodiments, the first transmission means 30 needs to be configured to allow proper transmission of forces and movements.

[0053] Referring now in particular to Figs 9a; 9b, 10a; 10b, and 11, further embodiments and variations of the first transmission means 30 and the second transmission means 20 will be described in some detail.

[0054] In one embodiment of the first transmission means which is particularly suitable for meshing with the second transmission means formed as a rack of teeth 20, the first transmission means 30 arranged in the bottom element 4 comprises a circular gear including at least one pinion 31 meshing to the rack of teeth 20 of the second transmission means.

[0055] The first transmission means 30 comprises in the embodiment shown a connecting portion 32 to the bottom element 4.

[0056] The at least one pinion 31 has a suitable width chosen to the specific purpose and the choice of profiling of the rack of teeth 20 of the second transmission means. Advantageously, the ratio between the width of the at least one pinion 31 and the width of the head portion 21 of the at least one rack of teeth 20 is at least 2:1, preferably at least 3:1.

[0057] The first transmission means arranged in said bottom element may also comprise a second pinion, configured to engage with the second rack of teeth, or alternatively with the same rack of teeth.

[0058] Although there is as such freedom of choice regarding the movements of the first and second transmission means as long as they ensure proper force and movement transmission, one embodiment which is particularly advantageous is when the first transmission means 30 comprises a rotational axis which is parallel with the longitudinal direction of the bottom element 4.

[0059] The principles underlying the invention may be used in all types of screening arrangements. This applies both to manually operated screening arrangements, and to screening arrangements in which the movement of the bottom element is carried out by means of a driving device.

[0060] In one embodiment (not shown in detail) the screening arrangement is electrically operated and the bottom element 4 comprises an electric motor connected to the first transmission means 30.

[0061] In a further development of this embodiment, the bottom element 4 further comprises a battery and a solar panel, said solar panel facing the exterior, and wherein the battery is chargeable by means of the solar panel, and wherein the battery powers the electric motor.

[0062] The profiling of the rack of teeth 20 of the embodiments of the invention shown and described in the above also include the choice of a suitable pitch and shape in all three dimensions of the side rail 10. Thus, in combination with the shape and dimensions in the width direction W and the depth direction D of the side rail, the shape and dimensions of the rack of teeth 20 in the longitudinal direction are to be determined as well in order to ensure optimum conditions both as regards manufacture and in use to attain satisfactory operability of the screening arrangement. In one embodiment, shown for instance in Figs 9a and 9b, the shape of the teeth of the rack 20 as seen in the longitudinal direction L of the side rail 10 is symmetrical to the shape of the teeth of the rack 20 in the width direction D of the side rail 10.

[0063] The materials of the elements involved are chosen according to the purpose and to provide secure engagement between the first and second transmission means, while at the same time providing a suitable expected lifetime of the elements.

[0064] In particular, the side rail is made of a suitable metallic material. This encompasses metals, metal alloys, reinforced metallic materials. One material which is suitable also from a manufacturing perspective is aluminium.

[0065] In the following, a method of manufacturing a side rail of a screening arrangement, said side rail including at least one flange and at least one rack of teeth in one or more of said flange or flanges will be described. Specific embodiments of the method will be described with particular reference to Figs 13 to 15.

[0066] In general, the method according to the invention comprises the steps of:

First providing a side rail blank of a metallic material. The material of the side rail blank is preferably aluminium but other materials are conceivable.

Second, a side rail is provided from the side rail blank to form a first flange extending substantially in the width direction W, a second flange extending substantially in parallel with the first flange, in the width direction W, a third flange connecting the first and second flanges and extending substantially in the depth direction D.

[0067] A rack flange is provided with a base portion connecting the rack flange to the one of the flanges, a head portion and a body portion connecting the base portion and the body portion of the side rail. The step of providing the rack flange may either be carried out in connection with extrusion of the side rail blank to form the side rail, or alternatively, in a separate step following manufacture of the side rail intermediate resulting from the step of providing the side rail from the side rail blank.

[0068] In further steps, the side rail is hardened, and the rack of teeth is formed from the rack flange integrally with one of the flanges of the side rail by rotating a gear while moving the gear and/or side rail relative to each other in the longitudinal direction of the side rail whereby the head portion of the rack of teeth is made wider, i.e. provided with a larger extent in the width direction W, than at least the part of the body portion of the rack which is adjacent to the head portion.

[0069] The head portion of the rack flange following the step of providing the rack flange is in one embodiment wider than at least the part of the body portion of the rack which is adjacent to the head portion.

[0070] Alternatively, the rack flange following the step of providing the rack flange is tapered and the head portion is made wider than at least the part of the body portion of the rack which is adjacent to the head portion during the step of forming the rack of teeth from the rack flange.

[0071] It is advantageous if the method further comprises the steps of pickling the side rail and anodizing the side rail, cf. Figs 13 to 15.

[0072] In one embodiment, the step of forming the rack is performed following the steps of hardening, pickling and anodizing the side rail. However, it is preferred that the step of forming the rack is performed before pickling and anodizing since this will render a more pleasant finished product.

[0073] Alternatively, the step of forming the rack is carried out before the hardening of the side rail.

[0074] In specific embodiments, a final step of shortening the side rail to a predefined length is also carried out.

[0075] Dependent on the manufacturing method, it is possible to allow the material to settle in a shape to form variations of for instance the head portion and any support portion of the side rail 10 as described in the above.

[0076] Further aspects include the following, non-exhaustive itemized list of not-shown embodiments:

A. A screening arrangement (3) for a window (1), preferably a roof window, comprising a frame (2) with a top member, a bottom member and two side members, the screening arrangement comprising:

at least one bottom element (4), and

two side rails (10) defining a longitudinal direction (L), a width direction (W) and a depth direction (D), the at least one bottom element (4) being movable with respect to the two side rails (10) between a non-screening position and a screening position by means of a drive means comprising

a first transmission means (30) comprising a circular gear including at least one pinion (31) arranged in said at least one bottom element (4), and

a second transmission means comprising two racks of teeth (20a, 20b) arranged in each of the two side rails (10) such as to extend substantially in the longitudinal direction (L) of the side rail (10), to engage with the at least one pinion (31) of the first transmission means (30),

each side rail (10) comprising a first flange (11) extending substantially in the width direction (W), a second flange (12) extending substantially in parallel with the first flange (11), in the width direction (W), and positioned to cover at least a part of the bottom element (4), and a third flange (13) connecting the first and second flanges (11, 12) and extending substantially in the depth direction (D), wherein said second transmission means is formed integrally in at least one of said flanges (11, 12, 13) of said side rail (10), and said side rail (10) is of an extrudable material, wherein the second transmission means comprises at least two racks of teeth (20a, 20b) to engage with the at least one pinion (31) of the first transmission means (30), and wherein the teeth of said racks (20a, 20b) have a base portion (23) provided at the at least one flange (11, 12, 13), a head portion (21) engaging the first transmission means (30), and a body portion (22) extending between the base portion (23) and the head portion (21), and wherein said at least two racks (20a, 20b) are formed integrally in the same flange (11), and said at least two racks (20a, 20b) being preferably substantially parallel with each other, and wherein said pinion (31) is provided with such a width that the at least one pinion (31) extends across and is configured to mesh with at least a part of each of the two parallel racks of teeth (20a, 20b).

B. A screening arrangement according to embodiment A, wherein the head portion (21) of each of the two racks of teeth (20) is wider, i.e. has a larger extent in the width direction (W), than at least the part of the body portion (22) of the rack which is adjacent to the head portion (21)

C. A screening arrangement according to embodiment A or B, wherein the first transmission means arranged in said bottom element comprises two pinions, the first pinion configured to engage with the first rack of teeth (20a) and the second pinion configured to engage with the second rack of teeth (20b).

D. A screening arrangement according to any one of embodiments A to C, wherein the first transmission means (30) comprises a rotational axis which is parallel with the longitudinal direction of the bottom element (4).

E. A screening arrangement according to embodiment D, wherein the first transmission means (30) comprises a connecting portion (32) to the bottom element (4).

F. A screening arrangement according to any one of embodiments A to E, wherein the screening arrangement is electrically operated and the bottom element (4) comprises an electric motor connected to the first transmission means (30).

G. A screening arrangement according to embodiment F, wherein the bottom element (4) further comprises a battery and a solar panel, said solar panel facing the exterior, and wherein the battery is chargeable by means of the solar panel, and wherein the battery powers the electric motor.

[0077] The invention should not be regarded as being limited to the described embodiments. Several modifications and combinations of the different embodiments will be apparent to the person skilled in the art. It should be noted that the above description of preferred embodiments serves only as an example, and that a person skilled in the art will know that numerous variations are possible without deviating from the scope of the claims.

List of reference numerals

[0078] 

1

roof window

2

frame

3'

prior art screening arrangement

4'

bottom element of prior art screening arrangement

5

pane

10'

side rail of prior art screening arrangement

3

screening arrangement

4

bottom element

10

side rail

11

first flange

12

second flange

13

third flange

14

extended portion of third flange

15

fourth flange

16

extended portion of fourth flange

17

support portion

18

fifth flange

19a

sixth flange

19b

seventh flange

20

second transmission means / rack of teeth

21

head portion

22

body portion

23

base portion

20a

one set of second transmission means / one rack of teeth

21a

head portion

22a

body portion

23a

base portion

20b

other set of second transmission means / other rack of teeth

21b

head portion

22b

body portion

23b

base portion

30

first transmission means / circular gear

31

pinion

32

connecting portion

L

longitudinal direction

W

width direction

D

depth direction

Claims

1. A screening arrangement (3) for a window (1), preferably a roof window, comprising a frame (2) with a top member, a bottom member and two side members, the screening arrangement comprising:

at least one bottom element (4), and

two side rails (10) defining a longitudinal direction (L), a width direction (W) and a depth direction (D), the at least one bottom element (4) being movable with respect to the two side rails (10) between a non-screening position and a screening position by means of a drive means comprising

a first transmission means (30) comprising a circular gear including at least one pinion (31) arranged in said at least one bottom element (4), and

a second transmission means comprising at least one rack of teeth (20) arranged in each of the two side rails (10) such as to extend substantially in the longitudinal direction (L) of the side rail (10), to engage with the at least one pinion (31) of the first transmission means (30),

each side rail (10) comprising a first flange (11) extending substantially in the width direction (W), a second flange (12) extending substantially in parallel with the first flange (11), in the width direction (W), and positioned to cover at least a part of the bottom element (4), and a third flange (13) connecting the first and second flanges (11, 12) and extending substantially in the depth direction (D),

characterised in that

said rack of teeth (20) of the second transmission means is formed integrally in at least one of said flanges (11, 12, 13) of said side rail (10), the teeth of said rack (20) having a base portion (23) provided at the at least one flange (11, 12, 13), a head portion (21) engaging the at least one pinion (31) of the first transmission means (30), and a body portion (22) extending between the base portion (23) and the head portion (21), that said side rail (10) is of an extrudable material, and that the head portion (21) of the rack of teeth (20) is wider, i.e. has a larger extent in the width direction (W), than at least the part of the body portion (22) of the rack which is adjacent to the head portion (21).

2. A screening arrangement according to claim 1, wherein the shape of the head portion (21) of the rack of teeth (20) is selected from the group comprising: substantially circular, bud-shaped, anvil-shaped, and T-shaped.

3. A screening arrangement according to claim 1 or 2, wherein the ratio between the width of the head portion (21) and the width of the body portion (22) at the part adjacent to the head portion is at least 1.05:1; preferably at least 1.2:1; and more preferably at least 2:1.

4. A screening arrangement according to any one of the preceding claims, wherein the ratio between the width, i.e. the dimension in the width direction (W), of the head portion and the height, i.e. the dimension in the depth direction (D), of the rack, from the base portion to the head portion, is up to 1:3, preferably up to 1:4.

5. A screening arrangement according to any one of the preceding claims, wherein the head portion (21) of the rack of teeth (20) has a tapered shape in the depth direction (D), preferably also the body portion (22).

6. A screening arrangement according to any one of the preceding claims, wherein the shape of the teeth of the rack (20) as seen in the longitudinal direction (L) of the side rail (10) is symmetrical to the shape of the teeth of the rack (20) in the width direction (D) of the side rail (10).

7. A screening arrangement according to any one of the preceding claims, wherein the teeth of the rack (20) are curved.

8. A screening arrangement according to any one of the preceding claims, wherein the side rails (10) comprise extruded profiles of aluminium.

9. A screening arrangement according to claim 8, wherein the at least one rack of teeth (20) is formed by extrusion to form a rack flange and at least one subsequent rack forming operation, the head portion (21) being preferably provided with a larger extent in the width direction (W) during the subsequent rack forming operation.

10. A screening arrangement according to any one of the preceding claims, wherein the at least one pinion (31) has a width, and wherein the ratio between the width of the at least one pinion (31) and the width of the head portion (21) of the at least one rack of teeth (20) is at least 2:1, preferably at least 3:1.

11. A screening arrangement according to any one of the preceding claims, wherein said rack of teeth (20) is formed in one flange (11, 12, 13), preferably in said first flange (11), and more preferably the at least one rack (20) is formed in the first flange (11) to protrude in the depth direction (D), away from the second flange (12).

12. A screening arrangement according to any one of claims 1 to 10, wherein said rack of teeth (20) is formed in said second flange (12) or said third flange (13) or, if the side rail (10) comprises a fourth flange (15), in said fourth flange (15).

13. A screening arrangement according to any one of the preceding claims, wherein said third flange (13) has an extended portion (14) extending from the first flange (11) in the depth direction (D) away from the second flange (12).

14. A screening arrangement according to any one of the preceding claims, wherein two parallel racks of teeth (20a, 20b) are provided and in which said pinion (31) is provided with such a width that the pinion (31) extends across and is configured to mesh with at least a part of each of the two parallel racks of teeth (20a, 20b).

15. A screening arrangement according to any one of claims 1 to 13, wherein two parallel racks of teeth (20a, 20b) are provided and in which two pinions are provided, which are configured to mesh with a respective rack of teeth (20a, 20b).

16. A method of manufacturing a side rail of a screening arrangement, said side rail including at least one flange and at least one rack of teeth in one or more of said flange or flanges, comprising the steps of
providing a side rail blank of a metallic material, preferably aluminium,
providing a side rail from said side rail blank to form a first flange (11) extending substantially in the width direction (W), a second flange (12) extending substantially in parallel with the first flange (11), in the width direction (W), a third flange (13) connecting the first and second flanges (11, 12) and extending substantially in the depth direction (D),
providing a rack flange comprising a base portion connecting the rack flange to the one of the flanges (11, 12, 13), a head portion and a body portion connecting the base portion and the body portion in said side rail by one of the following steps

i. the rack flange is formed by extrusion of the side rail blank in the step of providing the side rail, or

ii. the rack flange is formed in a separate step,

hardening the side rail, and
forming the rack of teeth from the rack flange integrally with one of the flanges of the side rail by rotating a gear while moving the gear and/or side rail relative to each other in the longitudinal direction of the side rail, whereby the head portion (21) of the rack of teeth (20) is made wider, i.e. provided with a larger extent in the width direction (W), than at least the part of the body portion (22) of the rack which is adjacent to the head portion (21).

17. The method of claim 16, wherein the head portion of the rack flange following the step of forming the rack flange is wider than at least the part of the body portion of the rack which is adjacent to the head portion.

18. The method of claim 16, wherein the rack flange following the step of forming the rack flange is tapered and the head portion is made wider than at least the part of the body portion of the rack which is adjacent to the head portion during the step of forming the rack of teeth from the rack flange.

19. The method of any one of claims 16 to 18, wherein the method further comprises the steps of pickling the side rail and anodizing the side rail, and wherein the step of forming the rack is performed following the steps of hardening, pickling and anodizing the side rail, or the step of forming the rack is performed after the step of hardening and before the steps of pickling and anodizing the side rail, or the step of forming the rack is performed before the step of hardening the side rail.

20. The method of any one of claims 16 to 19, comprising a final step of shortening the side rail to a predefined length.

Drawing