EP1674634B1

EP1674634B1 - A roof window frame adapted for standardized manufacture

Info

Publication number: EP1674634B1
Application number: EP05388116.5A
Authority: EP
Inventors: Lars Kristensen
Original assignee: VKR Holding AS
Current assignee: VKR Holding AS
Priority date: 2004-12-24
Filing date: 2005-12-23
Publication date: 2019-05-15
Anticipated expiration: 2025-12-23
Also published as: PL1674634T3; EP1674634A1

Description

Field of the invention

This invention relates to a window frame, in particular to a window frame for a roof window, which comprises a top frame member, two side frame members and a bottom frame member. Said window frame constitutes an openable roof window with a sash attached thereto. A window sash may be readily hinged to such a window frame at a top portion or a central portion thereof to form a top-hung window or a centre-hung window, respectively, thereby satisfying different requirements of different users.

Background of the invention

US 2004/0016187 A1 describes a door frame for a side hung door with a top frame member and two side frame members but no bottom frame member. One of the side frame members comprises hinge mortises, which may be pre-manufactured or be chiselled out on site. One hinge mortise is positioned centrally in the one side frame member, and further hinge mortises are positioned spaced apart from the centrally positioned hinge mortise and also spaced apart from the top frame member and the bottom of the side frame members, respectively. The other side frame member comprises a lock mortise. Furthermore, the top frame member comprises an interior wood side and an exterior hardboard side, and the side frame members comprises a similar construction US 2004/0016187 A1 further describes a window frame made of engineered wood for a façade window of the type that is opened by sliding the frame upwards. As such a window is not hinged, this window frame does not comprise hinge mortises, but is otherwise described as comprising much the same structure as the door frame.
BE 535898 A describes to a façade window of the pivot type, the window sash of which is able to pivot optionally about one of two different horizontal axes. This is achieved by means of a hinge part, one end of which is secured in the one cutout provided in a side member of the window frame. The other end of the hinge part can either also be secured in the cutout or be able to pivot out from the cutout. If the other end of the hinge part is secured in the cutout, the window sash pivots about a central axis. If the other end of the hinge part is able to pivot out from the cutout, the window sash pivots about a top axis.
When a window is mounted in a roof, a window frame is firstly attached to the roof and then a sash with a pane is pivotally attached to the frame to form an openable roof window, so as to satisfy a requirement for indoor lighting as well as ventilation.
To achieve a good sealing, the installation direction of a roof window is given when it is mounted in a roof, i.e. the outside surface and the inside surface, the top member and the bottom member are all given, such that the installation must be carried out in a given way. Generally, the window frame and sash both have a rectangular frame structure, as shown in Figs. 1 and 2. For a mounted window, the rectangular window frame 200 and sash both comprise two transverse members, i.e. a top frame member 220 and a bottom frame member 230 when this window is mounted on a pitched roof, and two side members 210 along the inclined roof. At the same time, according to the installation direction, for a window frame and a sash, its surface towards the inside of a building is generally referred to as a bottom surface, while a surface towards the outside of the building is referred to as a top surface; and a wall towards an enclosure which is enclosed by four frame members of a window frame (or a sash frame) is referred to as an inner wall, while an outer surface opposite to the inner wall is referred to as an outer wall.
Depending on the location where the window sash is hinged to a window frame, pitched roof windows can be divided into two groups, i.e. top-hung windows and centre-hung windows. Fig. 1 shows a top-hung window, in which a sash 100 is coupled at its top portion (i.e. upper end of the sash when mounted in the pitched roof) to the window frame 200 at a top portion of an inner wall (i.e. surface towards a rectangular enclosure by the window frame) of side frame member 210. The sash 100 pivots on a top hinge as a whole toward the outside during opening of the window. For a top-hung window, a support means 4, such as a spring, a gas spring or a lifting means, is provided between the sash 100 and the frame 200 so that the sash 100 may be readily opened and kept in the open state. A lower end of the support means 4 is attached to the inner wall at a central portion of the side frame 210 of the window frame, and an upper end is secured to the outer wall of the side sash member of the sash 100. Fig. 2 shows a centre-hung window in which hinge 3 is substantially centrally arranged on the side members of the window frame 200 and window sash 100. The sash pivots on the central hinge during opening of the window, wherein a portion above the hinge pivots towards the inside while a portion below the hinge pivots towards the outside.
Since the hinge attaches the sash to the frame and functions as a pivot axis for the sash, installing accuracy of the two hinges determines rotating flexibility of the sash; furthermore, since the hinge for attaching the sash and providing a pivot axis is installed between the inner wall of the side frame member and the outer wall of the side sash member, a cutout for installing the hinge is generally defined at a proper position of the inner wall of the side frame member to reduce a gap between the inner wall of the side frame member and the respective outer wall of the side sash member, thereby improving the sealing between the frame and the sash. The cutout extends upwardly to the top surface of the side frame member, so that a hinge may be installed therein. The cutout ensures an accurate installation of the hinge as well as a fast assembling when the pitched roof window is assembled and/or mounted; at the same time the gap between the frame and the sash is reduced to improve sealing.
For a top-hung window, it is necessary that a certain space is provided between the side frame member and side sash member due to the existence of the support means. As a result, in the prior art, the gap between the side frame member and side sash member is quite large, which makes a sealing very difficult, support means visible from the inside thus affecting the overall appearance.
The window frame of the pitched roof window, particularly the window frame made of wood material, is a rectangular frame assembled by four members, i.e. the top member, the bottom member and the two side members. During manufacture, the four members with required shapes are firstly manufactured separately then assembled into an integral frame. Therefore, based on respective features of the top-hung window and the centre-hung window, a supplier provides different types of frame elements and frames, wherein these elements are distinguished by the position of the cutout for hinge installation, either at the central portion or at the top portion. Although such frames with different structures are user-friendly, the design, manufacture, assembly, and transportation thereof are problematic. Manufacture of frames with different structures leads to a certain increase of workload for production design, complication of manufacturing management and preparation, reduction of manufacturing efficiency and thus a certain increase of cost. Furthermore, the consumer demand for different types of windows is constantly varying, leading to an overstock of a certain type of frame against a shortage of other types of frames. At the same time, it is necessary to store side frame members with different structures to satisfy different assembling and servicing requirements, which lead to an increase of spare parts and spare materials, and ultimately, a surplus storage of the product. From the point of view of a designer, a manufacturer and a supplier, it is always desirable for a product to consist of as many standard elements as possible so that it is well-compatible with other products, thus the costs for designing, manufacturing, stocking and servicing are reduced, since a standardized manufacture is the key in a productive specialization to improve productive efficiency and reduce manufacturing costs in modern industry. Therefore, suppliers are confronted with the problem of: how to balance a requirement for a standardized manufacture of frames and other elements and a user's demand for various windows.

Summary of the invention

An object of the invention is to provide a window frame adapted for a top-hung structure as well as a centre-hung structure based on structural differences between the top-hung window and the centre-hung window, in which as many standard elements as possible are employed and non-standard elements are reduced, such that the designing, manufacturing and assembling costs may be reduced while various functional requirements are satisfied; at the same time, in a top-hung window, the support means may be so shielded that the window may have an aesthetic appearance.
The technical solution of the invention is described as following.
According to an aspect of the invention, a window frame adapted for standardized manufacture comprises two side frame members, a top frame member and a bottom frame member, with all these frame members coupled together to form a rectangular frame structure. Each side frame member defines a concave central cutout for receiving a central hinge or support means at a longitudinal central portion of its inner wall, and another concave top cutout for receiving a top hinge at a longitudinal top portion of its inner wall where the top frame member connects with the side frame member. The central cutout and top cutout are arranged at an upper portion of the side frame and extend upwardly to an top edge of the side frame member. Since the side frame member for a roof window frame according to the present invention defines both a top cutout at a top portion of the inner wall and a central cutout at a central portion of the inner wall, respectively, said frame is suitable for both a top-hung window and a centre-hung window, i.e. a single structure fit for two different windows, which makes the use of a standard window frame possible. Therefore, only a window frame with a unique structure is needed throughout design and manufacture, wherein said frame can meet requirements for both a top-hung window and a centre-hung window. Thus, the productive flow and management can be greatly simplified, an operator can work with great proficiency, and the production rate can be greatly improved. Moreover, the need for spare parts can be minimized, and frame servicing is easier due to employment of such standard elements. Further, since the support means may be arranged in the central cutout, the support means can be shielded in the cutout, such that the window has an aesthetic appearance as well as an improved air-tightness.
Width of the central cutout of the side frame member reduces in a longitudinal direction of the side frame member from the top end to bottom end thereof to form a slanting cutout. In this way, in the case of a top-hung window, the central cutout inclines consistently with the support means, such that on the one hand the support means may be received in the frame and invisible from the inside, which gives the product an aesthetic appearance, on the other hand processing of a slanting central cutout is simpler.
The side frame member defines a step on its inner wall for a better sealing between the sash and the frame, and the step is arranged in a longitudinal direction of the side frame member. If the step of the side frame member engages with a step formed on an outer wall of the sash member, the sealing area of a gasket may be increased, a passage for an air flow through the gap between the frame and the sash becomes zigzag so that an air flow rate is reduced, and rainwater in said passage is prevented from directly flowing down to the bottom of the sash. Thereby a favorable sealing is obtained. The step also provides a support for the sash, which not only reduces stresses on the hinge, whereby service life of the hinge is prolonged, but also prevents the sash from over rotating during window closing.
Similarly, the top frame member defines a step on its inner wall such that its inner wall is stepped too.
Since the upper sash of a centre-hung window rotates towards the inside during a window opening process, the step of the top frame member is arranged in an direction opposite to that of a top-hung window. Therefore, the position and direction of a top frame step for a top-hung window is different from that of a centre-hung window, leading to different top frame members in these two types of windows. In order to use as many standard elements as possible in a window frame and thus reduce non-standard elements as much as possible, an assembled top frame structure is employed in this invention; i.e. the top frame member comprises a basic top frame member and an extra top frame member. In this way, the basic top frame member, which constitutes most of the top frame member, is still a standard element. In other words, the basic top frame member in a top-hung window and a centre-hung window is identical to each other. The top frame member can be used in different windows with a simple change of the extra top frame member.
In a further aspect of the invention a window frame adapted for standardized manufacture is provided, said window frame comprising two side frame members, a top frame member and a bottom frame member, with all frame members coupled together to form a rectangular frame structure, the window frame being characterized in that said top frame member comprises a basic top frame member and an extra top frame member, wherein the width of the basic top frame member is different from that of the extra top frame member and their inner walls are not aligned, thereby forming said step on the inner wall.
The present invention is advantageous in that it provides a window frame adapted for standardized manufacture, the top, bottom and side frame members thereof being standardized as much as possible, such that the same frame can be used for a top-hung window as well as a centre-hung window, wherein the only change needed is a replacement of some local elements. As a result, standardization design and production can be achieved and production costs can be reduced.

Brief description of the drawings

Fig. 1 is a schematic view of a top-hung window;
Fig. 2 is a schematic view of a centre-hung window;
Fig. 3 is a perspective view of an assembled window frame adapted for standardized manufacture according to this invention;
Fig. 4 is a schematic view showing an inner wall of a right side frame member of the window frame adapted for standardized manufacture of Fig. 3.
Fig. 5 is an enlarged cross-sectional view taken along line A-A of Fig. 4;
Fig. 6 is a schematic view showing engagement between the side frame member of Fig. 5 and a sash;
Fig. 7 is a perspective view showing an alternative assembled window frame adapted for standardized manufacture according to this invention;
Figs. 8 and 9 are cross-sectional views of an assembled top frame member;
Fig. 10 is a schematic view showing a rabbet structure between the top frame member of Fig. 8 and the side frame member;
Fig. 11 is a schematic view showing a rabbet structure between the top frame member of Fig. 9 and the side frame member;
Fig. 12 is a cross-sectional view showing a side frame member with an extra plate;
Fig. 13 is a cross-sectional view of a bottom frame member; and
Figs. 14 and 15 are schematic views showing engagement between a sash and a frame top and side member, respectively.

Detailed description of the invention

Embodiments of the present invention will now be described in detail in conjunction with the accompanying drawings.
As shown in Figs. 3 and 7, a window frame adapted for standardized manufacture comprises two side frame members 210, a top frame member 220 and a bottom frame member 230, with all frame members coupled together to form a rectangular frame structure. Each of the side frame members 210 defines, at a central portion along the longitudinal direction of its inner wall, a concave central cutout 211 for receiving a central hinge or a support means, and at a top portion along the longitudinal direction of its inner wall, where the top frame member 220 is attached to the side frame members 210, defines a concave top cutout 212 for receiving a top hinge. Referring to Fig. 4 in conjunction with Fig. 5, the central cutout 211 and top cutout 212 of the side frame member 210 are arranged above the middle of the side frame and extend upwardly to a top edge 213 of the inner wall, whereby an opening is formed at the top edge to facilitate an installation of a hinge. The hinge is simply fitted into the corresponding cutout 212 or 211 to form a top-hung window or centre-hung window during assembly. When designed and manufactured, the central cutout 211 and the top cutout 212 are both provided in the side frame member regardless of window style. In this way, separate design, manufacture and storage can be avoided. Thus, the workload in the above process can be reduced, which is advantageous for an efficient production. For a top-hung window with support means, as shown in Fig. 6, the support means 400 can be installed in the central cutout 211, which may reduce the gap between the frame and the sash as well as form a favorable airtight sealing through overlapping with the sash 100. Further, the support means 400 is invisible from inside of the building such that the window as a whole has an aesthetic appearance.
As shown in Fig. 4, the central cutout 211 and the top cutout 212 in the present embodiment are designed to be arc-shaped, which provides an aesthetic appearance as well as an excellent structural property (preventing an occurrence of material breakage at these cutouts).
As shown in Fig. 4, the width of the central cutout 211 gradually reduces from the top end to the bottom end thereof in a longitudinal direction of the side frame member 210, so as to form an inclined cutout. The central cutout has an inclination corresponding to that of the support means when the window is in a closed state. This inclination, in addition to ensuring an easy installation of the hinge and the support means, leads to an as-few-as-possible material cut-out, guarantees sufficient structural strength of the cutout, and thus prevents the frame from breaking at the cutout due to too much material having been cut out.
Considering the requirement for installing a long support means, the central cutout 211 is designed to be larger than the hinge. Therefore, at least one positioning recess 214' for the central hinge or an installation hole 214 for the support means is defined in the inner wall at a central position of the central cutout, to facilitate an accurate installation of the hinge. The installation hole 214 for the support means may be a counterbore (not penetrated) or a through hole.
A gap is provided between the side frame member and side sash member so that the sash may pivot freely and elements such as the hinge may be readily installed. If the gap is too large, wind, rain, duct etc. can easily get through and enter the room. Therefore, a gasket is generally attached to the sash to seal the gap. However, the gasket rubs against the inner wall of the frame during opening/closing of the window, so that the gasket tends to get worn and fall off, resulting in a failure of sealing. Further, since the walls of the frame and the sash are straight, the gap therebetween is also straight. As a result, wind may easily get through; particularly, rainwater or slush soaking said gap may easily get into the room along the straight frame wall. In view of the above aspects, a preferable embodiment according to the invention is shown in Fig. 5, in which the side frame member 210 forms a step 215 in its inner wall for a sealing between the sash and the frame, and the step 215 is arranged in a direction parallel to the longitudinal direction of the side frame member, such that the inner wall of the side frame member forms a stepped surface rather than a straight surface from the top down to the bottom. As shown in Fig. 6, not only a support for the sash 100 is provided by the step 215 but also the gasket is held down on an upward surface of the step 215 to form a press sealing rather than a clamp sealing. The gasket will not rub against the inner wall of the window frame whether the sash 100 is being opened or closed, thereby a failure of the sealing is prevented. More particularly, such a structure allows for the gap defined between the side sash member and the frame side sash to be cornered rather than being straight, thereby a wind speed will be greatly reduced after the wind passes through the corner, i.e. the wind is difficult to blow into the room or bring the rainwater and duct into the room. Therefore, the sealing is greatly improved.
In Figs. 3-5, the step 215 of the inner wall in the side frame member extents over the side frame member 210 in the length direction to form a desirable sealing along all side frame members. Fig. 7 shows another side frame member 210, in which no step is provided in an upper portion above the central cutout 211 of the side frame member, instead, the step 215 is only provided in a lower portion of the side frame member, i.e. the portion below the central cutout 211. Such a frame is particularly suitable for a centre-hung window, since said upper portion of the sash is closed from the inside such that an upward step above the hinge can have little benefit on the sealing. According to a preferred embodiment of the invention, the step formed on the side frame member extents over the side frame member in the length direction thereof as shown in Figs 3 to 5, while an extra plate 216 is attached to the inner wall of the side frame member 210 at the upper portion which is above the central cutout 211, said extra plate being fastened on the side frame member 210 by screws or nails. Further, a bottom edge 2161 of the extra plate 216 is disposed on the step 215 of the side frame member such that a downward step 215' is formed since the extra plate 216 protrudes toward the inner side of the frame, as a result, the upper portion of the window can also obtain a good sealing effect from the downward step 215'. In the case of a centre-hung window, two opposite steps are respectively arranged at the upper portion and the lower portion of the frame to sealingly engage with the sash, whereby an optimal sealing effect can be obtained. Since the extra plate 216 is attached to the side frame member 210 by screws or nails, the basic portion of the side frame member 210 is still a standard element. Whether an extra plate 216 is needed can be decided when a window is installed, depending on whether the window is centre-hung or top-hung.
As shown in Fig. 4, the central cutout 211 of the inner wall in the side frame member 210 extents to the step 215 such that sufficient installation space is available for support means.
Moreover, to improve sealing between the top frame member and sash, the top frame member is also provided with a step on its inner wall such that the inner wall is stepped. Since the opening/closing direction of the sash relative to the respective top frame member is opposite in a centre-hung window and a top-hung window, it is necessary to form steps in opposite directions in two cases. A standard frame must satisfy these two installation requirements both for a top-hung window and for a centre-hung window. According to the preferred embodiment of the invention, the top frame member comprises as many standard elements as possible. In this case, the top frame member possesses an assembled structure, which comprises a basic top frame member as a standard element and an extra top frame member selected as desired, with the width of the basic top frame member different from that of the extra top frame member so as to form a step on the inner wall. The extra top frame member is fixed to the basic top frame member by screws or nails. As shown in Figs. 8 and 9, Fig. 8 shows a top frame member construction for a top-hung window, and Fig. 9 shows a top frame member construction for a centre-hung window. In the two constructions of Figs. 8 and 9, the basic top frame members 221 as standard elements have identical shapes and structures, with a groove 222 defined in their inner walls along the longitudinal direction, wherein a gasket (not shown) is embedded in the groove 222. The extra top frame member for a top-hung window of Fig. 8 is a lateral wood piece 223 with a width thereof smaller than that of the basic top frame member 221 so that a step 225 is naturally formed on the inner side. In the top frame member for a centre-hung window of Fig. 9, the extra top frame member comprises an outer piece 226 and an inner piece 224 sandwiched between the out piece 226 and the basic top frame member 221, wherein the width of the inner piece 224 is larger than that of the basic top frame member 221 while the width of the outer piece 226 is smaller than that of the basic top frame member 221. Further, the width of the outer piece 226 is equal to that of the piece 223 of Fig. 8. Although the inner piece and the outer piece of Fig. 9 may be integrally formed, such a structure requires a larger piece of wood material and a part of material cut from the wood material (the portion enclosed by dash lines in Fig. 9) is wasted, causing a waste of resources; while in a two-piece construction of this case, less material is required for each piece of the extra top frame member, which can improve utilization rate of the material as well as reduce costs. The wider inner piece 224 is a wider piece, which may be adapted for a special lock device which locks the sash through the inner piece 224 so that the window cannot be opened.
Since the step on the inner wall of the top frame member is formed by assembling the extra top frame member on the basic frame member, the basic top frame member 221 may be used as a standard element, and extra top frame members are attached to the basic top frame member 221 as desired. The attachment of the extra top frame member may be carried out during frame assembly or window installation. To this end, the extra top frame member may be fixed to the basic top frame member by screws or nails to facilitate assembly.
In the case of a wooden frame, the side frame members 210 joggle with the top and bottom frame members 220 and 230 by means of tenon-mortise joints at ends of these wood pieces. Figs 10 and 11 show a tenon-mortise joint. Fig. 10 shows the tenon-mortise joint between the top frame member and left side frame member of Fig. 3; and Fig. 11 shows the tenon-mortise joint between the top frame member and right side frame member of Fig. 7. The side frame members 210 of Figs. 10 and 11 are both standard elements, identical to each other, and both have an identical tenon-mortise joint at the top end thereof. Besides joggling with the basic top frame member, the side frame member 210 at its top end has a mortise for connecting with the extra frame member. Further, except for the extra top frame member, the tenon-mortise joint of the basic top frame member and the connecting structure between the basic top frame member are also identical to the side frame member. Referring to Figs. 8 and 10, it is understood that a cuboid space 227 is defined between the end mortise of the side frame member 210 and the extra piece 223, since the piece 223 is narrower than the basic top frame member 221 to form the step. Therefore, it is possible to fill one or more cubic blocks into the cuboid space 227 to improve aesthetic appearance and integrality of the window. Although the cuboid space 227 may be avoided by widening the piece 223 at the ends thereof, this is not a preferable solution since more wood is required and the piece 223 should be made from larger woods, which will certainly lead to a larger wood consumption as well as higher costs, and as a result, a departure from the original goals of standardized manufacture. Referring to Fig. 9, in the tenon-mortise joint in Figure 11, since the width of the inner piece 224 is larger than that of the basic top frame member 221 and outer piece 226 and the inner piece 224 protrudes toward the inner side of the frame, an opposite step is formed protruding from the inner wall of the basic top frame member 221. In this way, both ends of the inner piece 224 are respectively inserted into mortises defined in the side frame members 210 to form a tight fitting while no cuboid space is formed. Insertion of the ends of the inner piece 224 and using the screws and nails for securing the extra top frame member cooperatively realize a convenient and firm fitting of the inner and outer piece 224 and 226 relative to the basic top frame member 221 and the side frame members 210. Thereby the whole frame may be secured.
As for a top-hung window, a fixed covering of the top coverings is fixed to the top surface of the top frame member, therefore a flange (i.e. flange 228 shown in Figs. 8 and 10) may be provided on the top surface of the extra piece 223 to accurately position the top coverings during assembly. It is possible to provide a single flange 228 which extends in a length direction of the extra piece 223; and it is also possible to provide two flanges, one for each end of the extra piece 223, wherein the flange is slightly higher than other portion of the top surface of the top frame member.
The extra pieces 223, 224 and 226 shown in Figs. 3, 7, 10 and 11 have the same length as the basic frame member, and the extra pieces abut against the corresponding parts of the end surface of the side frame member 210. Alternatively, it is also possible that both end surfaces of the extra pieces 223, 224 and 226 abut against inner walls of the side frame member 210, i.e. the extra piece is shorter and the top end of the side frame member 210 extends further upwardly to sandwich the extra pieces between the left side frame member and right side frame member.
Since the extra top frame member is fixed to the basic top frame member by nails or screws, to achieve a tighter fitting and an accurate positioning, the extra piece 223 consisting of the extra top frame member may engage with the basic top frame member 221 by a convex-concave structure extending in a longitudinal direction of the extra piece 223 and the basic top frame member 221. Such a convex-concave structure may comprise a groove defined on the basic top frame member 221 in the longitudinal direction thereof and a flange formed on the extra piece 223, with the flange on the extra piece 223 embedded into the groove of the basic top frame member. Alternatively, the convex-concave structure may comprise a flange 229 formed on the basic top frame member 221 in the longitudinal direction thereof and a groove defined in the extra piece 223, wherein the flange 229 of the basic top frame member is embedded into the groove of the extra piece 223, as shown in Figs. 8 and 10.
Similarly, engagement(s) between the outer piece 226 and inner piece 224 and/or between the inner piece 224 and the basic top frame member 221 is/are obtained by a convex-concave structure to form a tight and accurate fitting as well as to facilitate assembly. Specifically, as shown in Figs. 9 and 11, the convex-concave structure between the inner piece 224 and the basic top frame member 221 comprises a flange formed on the basic top frame member 221 in the longitudinal direction thereof and a groove defined in the inner piece 224, with the flange of the basic top frame member 221 embedded into the groove of the inner piece 224. Alternatively, the convex-concave structure between the inner piece 224 and the basic top frame member 221 comprises a groove defined in the basic top frame member 221 in the longitudinal direction thereof and a flange formed on the inner piece 224, wherein the flange of the inner piece 224 is embedded into the groove of the basic top frame member 221. Also, the convex-concave structure of the inner and outer pieces 224 and 226 comprises a groove defined in the inner piece 224 in the longitudinal direction of the inner piece 224 and a flange formed on the outer piece 226, with the flange of the outer piece 226 embedded into the groove of the inner piece 224, as shown in Figs. 9 and 11. Alternatively, the convex-concave structure comprises a flange formed on the inner piece in the longitudinal direction of the inner piece and a groove defined in the outer piece, wherein the flange of the inner piece is embedded into the groove of the outer piece.
To improve the sealing between the sash and the bottom frame member, the bottom frame member 230 forms a step 235 on its inner wall in a longitudinal direction thereof so that a tight sealing is achieved, thus forming a stepped inner surface. Since the relative positions between the bottom sash and the frame in a top-hung window is the same as that in a centre-hung window, the bottom frame member 230 is identical in these two types of the windows. Although the step 235 is formed on the inner wall of the bottom frame member, the bottom frame member 230 is still a standard element.
As shown in Figs. 5 and 12, a flange 218 is formed on a top surface of two side frame members 210 in the longitudinal direction thereof for positioning the covering. It is advantageous that the inner side edge of the covering is flush with the edge of the flange so that the covering may be easily positioned.
As shown in Figs 5, 8, 9 and 13, recesses 250 are defined in bottom surfaces of the top, bottom and side frame members so that a window sheath may be easily fixed.
Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.

Claims

A roof window with a window frame adapted for standardized manufacture, said window frame comprising two side frame members (210), a top frame member (220) and a bottom frame member (230), with all frame members coupled together to form a rectangular frame structure, characterized in that each side frame member (210) defines a concave central cutout (211) adapted for receiving a central hinge and a support means of the roof window at a longitudinal central portion of its inner wall, and a concave top cutout (212), separate from said central cutout (211), adapted for receiving a top hinge of the roof window at a longitudinal top portion of its inner wall where the top frame member (220) connects with the side frame member (210), and that said central and top cutouts (211 and 212) are arranged at an upper portion of the inner wall of the side frame and extend upwardly to the top edge (213) of said inner wall of the side frame member (210).
A roof window according to claim 1, characterized in that the central cutout (211) and/or the top cutout (212) are/is arc-shaped.
A roof window according to claim 1 or 2, characterized in that the width of said central cutout (211) of the side frame member (210) reduces in a longitudinal direction of the side frame member (210) from the top end of the side frame member (210) to the bottom end of the side frame member (210) to form a slanting cutout.
A roof window according to any one of the preceding claims, characterized in that at least one positioning recess (214') for the central hinge is defined at a middle position of the central cutout (211).
A roof window according to any one of the preceding claims, characterized in that at least one counter bore and/or through hole (214) for the support means is defined in the central cutout (211).
A roof window according to any one of the preceding claims, characterized in that the side frame member (210) defines a step (215) in its inner wall for a better sealing between the sash and the frame, wherein the step (215) is in a longitudinal direction of the side frame member (210), such that the inner wall is stepped, said step (215) on the inner wall of the side frame member (210) preferably extending along the entire length of the side frame member (210).
A roof window according to claim 6, characterized in that an extra plate (216) is attached to the inner wall of the side frame member (210) by screws or nails, wherein a bottom edge of the extra plate (216) is disposed on said step (215) of the side frame member (210), said central cutout (211) preferably extending downwardly to said step (215).
A roof window according to any one of the preceding claims, characterized in that said top frame member (220) defines a step on its inner wall such that the inner wall is stepped.
A roof window according to claim 8, characterized in that said top frame member (220) comprises a basic top frame member (221) and an extra top frame member (223), wherein the width of the basic top frame (221) member is different from that of the extra top frame member (223) and their inner walls are not aligned, thereby forming said step on the inner wall.
A roof window according to claim 9, characterized in that the extra top frame member (223) is attached to the basic top frame member (221) by screws or nails.
A roof window according to claim 9, characterized in that the basic top frame member (221) defines a groove (222) in its inner wall in its longitudinal direction, and a gasket is arranged in the groove.
A roof window according to claim 9, characterized in that the side frame members (210) joggle with the top and bottom frame members (220 and 230), and the side frame member (210) defines a mortise at its top end for connecting with the extra top frame member (223).
A roof window according to claims 9, characterized in that said extra top frame member (223) is an extra lateral piece.
A roof window according to claim 13, characterized in that a flange forms on the top surface of the extra top frame member (223) for positioning a top covering, said flange preferably being a single piece and extending in a longitudinal direction of the extra top frame member (223).
A roof window according to claim 12, characterized in that the length of the extra top frame member (223) is the same as that of the basic top frame member (221), wherein the extra top frame member (223) correspondingly abuts against the end surfaces of the side frame members (210).
A roof window according to claim 12, characterized in that the two end surfaces of the extra top frame member (223) abut against the inner walls of the side frame members (210).
A roof window according to claim 13, characterized in that a block is filled into a mortise of the side frame member (210), wherein the side frame member (210) is correspondingly connected to the extra top frame member (223) at said mortise.
A roof window according to claim 12, characterized in that the extra top frame member (223) engages with the basic top frame member (221) through a convex-concave structure extending in a longitudinal direction of the extra top frame member (223) and the basic top frame member (221).
A roof window according to claim 18, characterized in that said convex-concave structure of the extra top frame member (223) and the basic top frame member (221) comprises a groove and/or a flange defined on the basic top frame member (221) in a longitudinal direction thereof and a flange and/or a groove formed on the extra top frame member (223), wherein the flange of the extra top frame member (223) is embedded into the groove of the basic top frame member (221).
A roof window according to claim 9, characterized in that the extra top frame member (223) comprises an outer piece (226) and an inner piece (224) overlapping with each other, wherein both ends of the inner piece (224) are respectively inserted into mortises defined in the side frame members (210), with the width of the inner piece (224) wider than that of the outer piece (226) and the basic top frame member (221), and the inner piece (224) extends toward inside of the frame and protrudes over the inner wall of the basic top frame member (221) to form said step.
A roof window according to claim 20, c h a r act e r i zed in that the length of the outer piece (226) is the same as that of the basic top frame member (221), wherein the side frames abuts against the extra top frame members (223) at tenon end surfaces of the outer piece (226).
A roof window according to claim 20, characterized in that both end surfaces of the outer piece (226) abut against the inner wall of the side frames.
A roof window according to claim 20, characterized in that engagement between the outer piece (226) and the inner piece (224) and/or between the inner piece (224) and the basic top frame member (221) are/is obtained through a convex-concave structure.
A roof window according to claim 23, characterized in that the convex-concave structure of the inner piece (224) and/or the basic top frame member (221) and/or the outer piece (226) comprises a groove and/or a flange defined in the basic top frame member (221) in a longitudinal direction thereof and a flange and/or a groove formed on the inner piece (224), wherein the flange of the inner piece (224) is embedded into the groove of the basic top frame member (221).
A roof window according to any one of the preceding claims, characterized in that the bottom frame member (230) defines a step (235) on its inner wall in a longitudinal direction thereof for a better sealing between the sash and frame, wherein a stepped surface is formed on the inner wall of the bottom frame member (230).
A roof window according to any one of the preceding claims, characterized in that a flange is formed on the top surface of two side frame members (210) for positioning a top covering.
A roof window according to any one of the preceding claims, characterized in that recesses are defined in bottom surfaces of the top, bottom and two side frame members (220, 230 and 210).
A roof window according to one or more of claims 1-27, characterized in that said top frame member (220) comprises a basic top frame member (221) as a standard element and an extra top frame member (223) selected as desired, wherein the width of the basic top frame member (221) is different from that of the extra top frame member (223) and their inner walls are not aligned, thereby forming a step on the inner wall.
A roof window according to claim 28, characterized in that the extra top frame member (223) is attached to the basic top frame member (221) by screws or nails.
A roof window according to claim 28, characterized in that the basic top frame member (221) defines a groove in its inner wall in its longitudinal direction, and a gasket is arranged in the groove.
A roof window according to claim 28, characterized in that the side frame members (210) joggle with the top and bottom frame members (220 and 230), and the side frame member (210) defines a mortise at its top end for connecting with the extra top frame member (223).
A roof window according to claims 28, characterized in that said extra top frame member (223) is an extra lateral piece.
A roof window according to claim 32, characterized in that a flange is formed on the top surface of the extra top frame member (223) for positioning a top covering, said flange preferably being a single piece and extending in a longitudinal direction of the extra top frame member (223).
A roof window according to claim 31, characterized in that the length of the extra top frame member (223) is the same as that of the basic top frame member (221), wherein the extra top frame member (223) correspondingly abuts against the end surfaces of the side frame members (210).
A roof window according to claim 31, characterized in that the two end surfaces of the extra top frame member (223) abut against the inner walls of the side frame members (210).
A roof window according to claim 32, characterized in that a block is filled into a mortise of the side frame member (210), wherein the side frame member (210) is correspondingly connected to the extra top frame member (223) at said mortise.
A roof window according to claim 31, characterized in that the extra top frame member (223) engages with the basic top frame member (221) through a convex-concave structure extending in a longitudinal direction of the extra top frame member (223) and the basic top frame member (221).
A roof window according to claim 37, characterized in that said convex-concave structure of the extra top frame member (223) and the basic top frame member (221) comprises a groove and/or a flange defined on the basic top frame member (221) in a longitudinal direction thereof and a flange and/or a groove formed on the extra top frame member (223), wherein the flange of the extra top frame member (223) is embedded into the groove of the basic top frame member (221).
A roof window according to claim 28, characterized in that the extra top frame member (223) comprises an outer piece (226) and an inner piece (224) overlapping with each other, wherein both ends of the inner piece (224) are respectively inserted into mortises defined in the side frame members (210), with the width of the inner piece (224) wider than that of the outer piece (226) and the basic top frame member (221), and the inner piece (224) extends toward inside of the frame and protrudes over the inner wall of the basic top frame member (221) to form said step.
A roof window according to claim 39, characterized in that the length of the outer piece (226) is the same as that of the basic top frame member (210), wherein the side frames abuts against the extra top frame members (223) at tenon end surfaces of the outer piece (226).
A roof window according to claim 39, characterized in that both end surfaces of the outer piece (226) abut against the inner wall of the side frames.
A roof window according to claim 39, characterized in that engagement between the outer piece (226) and the inner piece (224) and/or between the inner piece (224) and the basic top frame member (221) are/is obtained through a convex-concave structure.
A roof window according to claim 42, characterized in that the convex-concave structure of the inner piece (224) and/or the basic top frame member (221) and/or the outer piece (226) comprises a groove and/or a flange defined in the basic top frame member (221) in a longitudinal direction thereof and a flange and/or a groove formed on the inner piece (224), wherein the flange of the inner piece (224) is embedded into the groove of the basic top frame member (221).
A roof window according to any one claims 28-43, characterized in that the bottom frame member (230) defines a step (235) on its inner wall in a longitudinal direction thereof for a better sealing between the sash and frame, wherein a stepped surface is formed on the inner wall of the bottom frame member (230).
A roof window according to any one of claims 28-44, characterized in that a flange forms on the top surface of two side frame members (210) for positioning a top covering.
A roof window according to any one of claims 28-45, characterized in that recesses are defined in bottom surfaces of the top, bottom and two side frame members (220, 230 and 210).