Lifting device for roof window

Abstract

A lifting device (10) for a roof window (100), comprising a lifting arm (14) adapted to be inserted between a main frame (1) of the roof window (100) and a sub-frame of the roof window, the lifting arm (14) having a first end (14a) rotatably connected to a carriage (30) and a second end (14b) rotatably connected to the carriage (30), the carriage is adapted to be slidably connected with the main frame (1) in a carriage guide (16), the second end is adapted to be rotatably connected with the sub-frame, the lift arm (14) and the carriage guide (16) extending along a length direction (L) defining a central plane (P), the central plane (P) extending along the length direction (L) and a height direction (H) perpendicular to the length direction (L), the forces exerted by the lift arms (14) on the central plane (P) are balanced.

Description

TECHNICAL FIELD

[0001] The utility model relates to a lifting device for roof windows, the lifting device has a lifting arm, the lifting arm is suitable for inserting between the main frame of roof window and the auxiliary frame of roof window, the lifting arm has first end and second end, the first end is connected to the slide in rotatable mode, the slide is suitable for being connected with the main frame in the slide guide in the mode that can slide, the second end is suitable for being connected to the auxiliary frame in rotatable mode, the lifting device still includes spring assembly, the spring assembly is configured to be coupled to the slide, the lifting device still includes push arm, the push arm has the first end rotatably connected to the slide guide and the second end rotatably connected to the lifting arm, the lifting arm and the slide guide extend along the length direction of the center plane, and the center plane extends along the length direction and the height direction perpendicular to the length direction. BACKGROUND

[0002] Windows for installation on inclined roof surfaces can be provided in a plurality of variants and comprise more or less complex operating structures to allow opening of the secondary frame or sash and to implement other functions such as ventilation. Such roof windows include the type hinged at or near the center, the top-hinged type, and finally the roof window which is top-hinged during normal operation but in which the sash can perform a rotation movement substantially at the central axis for cleaning or for providing an alternative operating mode. The top-hinged type of roof window has a first axis of articulation provided by the top-hinged device to provide a first operating condition, while in a second operating condition the rotation of the sash is performed by means of an intermediate frame in which the sash is articulated to provide a second axis of articulation. Typically, one of the articulations of the device will be located on either side of the roof window to define a substantially horizontal axis of articulation.

[0003] Examples of top-hinged windows with a second operating condition are disclosed, for example, in the Applicant's WO-A-89 / 10460, EP 0 733 146 B1, EP 1 873 323 B1, EP 2 762 665 A2 and WO 2019 101 281 A1. In order to enable the window sash to rotate approximately 180° to a convenient cleaning position, the sash structure is connected with an intermediate frame having a frame arm which, in the closed position of the window, is positioned between the upper portion of the frame and the sash side members and, during normal use of the window as a top-hung window, follows the sash side members.

[0004] Furthermore, the force required to open and operate the roof window is influenced by the inclination of the roof on which the window is installed.

[0005] In roof windows which operate fully or partially about a hinge axis at the top, it is known to balance at least part of the weight of the movable parts by means of a lifting device. The purpose of such an arrangement is to facilitate opening of the window, and the dimensions can be chosen such that the spring can keep the top-hinged frame balanced in the desired open position.

[0006] For example, such a lifting device is disclosed in the applicant's WO 2019 / 101281 Al, in which a spring assembly acts as a force balancing element for the sash carrying frame by operating on a lifting arm attached to the frame.

[0007] EP 4 215 706 Al discloses another example of a support system for a window.

[0008] However, despite the fact that the lifting devices in the above examples are able to provide the desired force balance to some extent, there is still room for improvement. Utility model content

[0009] Against this background, it is an object of the utility model to provide a lifting device for a roof window which has improved stability while allowing the desired movement pattern and ease of operation.

[0010] This is achieved by a lifting device of the kind mentioned in the introduction. A lifting device for a roof window, the lifting device comprising a lifting arm adapted to be inserted between a main frame of the roof window and a secondary frame of the roof window, the lifting arm having a first end rotatably connected to a carriage adapted to be connected in a slidable manner to the main frame in a carriage guide, and a second end adapted to be rotatably connected to the secondary frame, the lifting device further comprising a spring assembly configured to be coupled to the carriage, the lifting device further comprising a push arm having a third end rotatably connected to the carriage guide and a fourth end rotatably connected to the lifting arm, the lifting arm and the carriage guide extending along a length direction defining a central plane, the central plane extending along the length direction and a height direction perpendicular to the length direction, the lifting arm comprising a first lifting arm and a second lifting arm arranged symmetrically with respect to the central plane, and a force exerted by the lifting arm onto the central plane is balanced.

[0011] According to an embodiment, the push arm comprises a first push arm and a second push arm positioned on opposite sides of the lifting arm and symmetrically positioned with respect to the central plane.

[0012] According to an embodiment, the at least two runners comprise a front runner configured to slide in a first track positioned proximate to the third end of the carriage guide, and a rear runner configured to slide in a second track positioned proximate to the fourth end of the carriage guide.

[0013] This arrangement provides an advantageous load distribution within the lifting device. The forces resulting from the weight of the movable parts of the roof window are aligned with respect to the central plane. This ensures that the torque on the various parts of the lifting device is minimised and makes the lifting device and roof window generally stable.

[0014] Other presently preferred embodiments and further advantages will be apparent from the detailed description that follows and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0015] In the following description, embodiments of the present application will be described with reference to the accompanying drawings, in which:

[0016] FIG. 1A is a perspective view from the inside of a roof window in an embodiment of the present application.

[0017] FIG. 1B is a perspective view from the outside of a roof window in an embodiment of the present application.

[0018] FIG. 1C is a side view of a roof window in an embodiment of the present application, with the sash in an open position.

[0019] FIG. 2A is a side view of a lifting device for a roof window in an embodiment of the present application in an open position.

[0020] FIG. 2B is a side view of a lifting device for a roof window in an embodiment of the present application in a closed position.

[0021] FIG. 3A is a perspective exploded view of the connection between an adjustment screw, an adjustment bushing and an adjustment arm in an embodiment of the present application.

[0022] FIG. 3B is a perspective exploded view of the connection between an adjustment screw and a lifting arm arranged in an opening of a lifting arm in an embodiment of the present application.

[0023] FIG. 3C is a perspective exploded view of the connection between a carriage arm, an adjustment system and a lifting arm in an embodiment of the present application.

[0024] FIG. 4Ais a side view of the lifting arm in a default position by adjusting the system connection with the carriage arm.

[0025] FIG. 4B is FIG. 4A a side view of the lifting arm, wherein the carriage arm is rotated relative to the lifting arm.

[0026] FIG. 4C is FIG. 4A and FIG. 4B a side view of the lifting arm, wherein the adjustment system is adjusted, whereby the connection point between the adjustment system and the carriage arm is changed.

[0027] FIG. 5 is an exploded view of the connection between the lifting arm and the carriage arm.

[0028] FIG. 6 is a perspective view of an assembly comprising a lifting arm, a carriage arm, an adjustment arm and an adjustment system according to an embodiment of the present application.

[0029] FIG. 7 is a perspective view of the shown lifting device previously mounted in the carriage in connection with a carriage guide according to an embodiment of the present application.

[0030] FIG. 8 is a perspective view of a lifting device for a roof window according to an embodiment of the present application, showing a centre plane P.

[0031] FIG. 9 is a front view of a lifting device for a roof window according to an embodiment of the present application, showing a centre plane P and a symmetrical arrangement of a lifting arm, a carriage arm and an adjustment arm according to an embodiment of the present application.

[0032] FIG. 10A is a close-up side view of an adjustment screw arranged in an opening in a lifting arm according to an embodiment of the present application.

[0033] FIG. 10B shows FIG. 10A an embodiment, wherein a tool is inserted to provide an external force on the adjustment system.

[0034] FIG. 10C shows FIG. 10A and FIG. 10B an embodiment, wherein the tool acts on the adjustment screw wheel.

[0035] FIG. 10D shows FIGS. 10A-10C an embodiment, wherein an external force is provided by means of rotating an external tool, whereby the adjustment screw is adjusted.

[0036] FIG. 10E An embodiment of the adjustment system is shown, wherein the position of the carriage arm on the adjustment screw has been changed by means of an adjustment of the adjustment screw, thereby changing the angle between the carriage arm and the lifting arm. FIGS. 10A-10D An embodiment of the adjustment system is shown, wherein the position of the carriage arm on the adjustment screw has been changed by means of an adjustment of the adjustment screw, thereby changing the angle between the carriage arm and the lifting arm.

[0037] FIGS. 11A-11B An embodiment of the adjustment system is shown, wherein the position of the carriage arm on the adjustment screw has been changed by means of an adjustment of the adjustment screw, thereby changing the angle between the carriage arm and the lifting arm.

[0038] FIG. 12 is a close-up bottom perspective view of the adjustment system according to an embodiment of the present utility model.

[0039] Legend

[0040] 1 main frame

[0041] 2 window sash 4 window grid

[0042] 4i inner window grid surface

[0043] 4e outer window grid surface

[0044] 5 operating assembly

[0045] 7 insulating frame

[0046] 10 lifting device

[0047] 14 lifting arm

[0048] 14a first end of the lifting arm

[0049] 14b second end of the lifting arm

[0050] 15 opening of the lifting arm

[0051] 16 carriage guide

[0052] 17 separate opening

[0053] 20 spring assembly

[0054] 21 hook

[0055] 30 carriage

[0056] 31 carriage arm

[0057] 31a fifth end of the carriage arm

[0058] 31b sixth end of the carriage arm 32 coupling plate 40 push arm

[0059] 40a third end of the push arm

[0060] 40b fourth end of the push arm

[0061] 41 rivet

[0062] 42i first rivet

[0063] 42ii second rivet

[0064] 43a front rail

[0065] 43b rear rail

[0066] 50 adjustment system

[0067] 52 adjustment arm

[0068] 52a seventh end of adjustment arm

[0069] 52b eighth end of adjustment arm 53 adjustment screw

[0070] 53i adjustment screw shaft

[0071] 53ii adjustment screw wheel

[0072] 53iii adjustment screw top

[0073] 54 bushing

[0074] 57 lift arm rivet

[0075] 60 screw bit

[0076] 70 front runner

[0077] 71 rear runner

[0078] 100 roof window

[0079] 141 first lift arm

[0080] 142 second lift arm

[0081] 311 first carriage arm

[0082] 312 second carriage arm

[0083] 401 first push arm

[0084] 402 second push arm

[0085] 521 first adjustment arm

[0086] 522 second adjustment arm

[0087] 701 first front runner

[0088] 702 second front runner

[0089] P center plane

[0090] L length direction

[0091] H height direction

[0092] a1 first angle

[0093] a2 second angle DETAILED DESCRIPTION

[0094] In the following, embodiments of the lifting device and the roof window will be described in more detail. When referring to the drawings, the terms upper, lower, upward, downward, top and bottom are adopted with respect to how the drawings are shown. The front view is adopted from the hinge and towards the window frame. The rear view is thus adopted when looking from the frame towards the hinge. If not mentioned otherwise, the longitudinal direction refers to the longitudinal direction along the length of the member. It should be understood that the arrangement shown in horizontal orientation is not the normal orientation when the window is installed on a sloping roof. The inner side faces towards the interior of the building in which the window is installed, while the outer side faces in the opposite direction towards the exterior of the building.

[0095] Throughout the various embodiments and drawings described herein, like reference numerals refer to similar elements.

[0096] Reference is first made to FIG. 1A and FIG. 1B , a roof window 100 is shown. The roof window 100 is intended to be installed in or on a sloping roof surface (not shown).

[0097] The roof window 100 comprises a main frame 1, a secondary frame, which will be referred to as sash 2 in the following, but can also comprise an intermediate frame, which is partly connected to the main frame 1, partly to a separate glass carrying unit which serves as sash.

[0098] Typically, the roof window comprises a window pane which comprises at least two layers of glass, preferably at least three layers of glass. The window can comprise an insulating glass unit (IGU).

[0099] The main frame 1 comprises a set of frame members, which comprises a top frame member, two side frame members and a bottom frame member. Correspondingly, the sash 2 comprises a set of sash members, which comprises a top sash member, two side sash members and a bottom sash member. Although the main frame 1 and the sash 2 are described as rectangular structures, some of the principles of the presented concept can also be applied to other geometrical shapes.

[0100] The pane 4 comprises a plurality of edge portions that are generally associated with the members of the sash 2. The outer pane surface 4e defines the plane of the roof window 100 in the assembled state of the roof window 100. The assembled state of the roof window 100 is achieved when the main components of the main frame 1 and the sash 2 have been assembled and the main frame 1 and the sash 2 are connected to each other, for example in the installed position in which the roof window 100 is ready for use. Correspondingly, the assembled state of the sash 2 is achieved once the main components of the sash 2 have been assembled and the assembled state of the main frame 1 is achieved when the main components of the main frame 1 are assembled. The term "main components" is to be understood as including the main components of the roof window that are required to perform all operational functions, but not accessories or ancillary equipment.

[0101] The inner pane surface 4i faces inwards, generally towards a room of a building below the roof surface on which the roof window 100 is installed.

[0102] In the embodiment shown, the sash 2 is openable relative to the main frame 1 to obtain one or more open positions. In such open positions, the sash 2 and the pane 4 are moved out of the plane of the roof window 100. As will be described hereinafter, the sash 2 is shown as top-hung, i.e. during normal use the sash 2 is rotated at or near the top frame members and the top sash members at the top of the roof window 100 about a generally horizontal axis of articulation. However, it is conceivable that some of the principles presented for the roof window are applied to different types of windows having other opening modes.

[0103] FIG. 1A Further details shown in the middle include an operating assembly 5, here shown as a handle. Other operating assemblies can also be present.

[0104] FIG. 1B Also shown in the middle are representative mounting brackets forming part of a plurality of mounting brackets that form a load transfer connection between the roof window 100 and the surrounding roof structure (not shown). Such roof structure can include rafters and battens, plywood or other construction materials.

[0105] An insulating frame 7 is shown. Insulation by the insulating frame is optional and can be provided along only some of the frame members or can be provided around all four frame members as shown.

[0106] Reference is made to FIG. 1C The roof window 100 is shown in a top-hung configuration. The roof window is top-hung, i.e. hinged at the top by means of an articulation assembly (not shown) connecting the main frame with the sub-frame.

[0107] The hinge assembly is configured such that it allows the sash 2 to be top-hung in a first operating state corresponding to normal use. That is, during normal use, the sash 2 is rotated about a substantially horizontal first axis of articulation at or near the top frame member and the top sash member between a closed position and an open position.

[0108] To assist the user in opening the sash 2, a lifting device 10 is provided, as will be described hereinafter. Reference is now also made to FIG. 2A The lifting device 10 comprises a lifting arm 14 interposed between the main frame 1 and at least one secondary frame, here the sash 2. The lifting device 10 further comprises a spring assembly 20 and a push arm 40, the spring assembly 20 being configured to be coupled to a carriage 30.

[0109] In FIG. 2A an embodiment of the lifting device 10 is shown from a side view, with one side of the carriage guide 16 removed, thereby showing the carriage 30 in connection with the spring assembly 20. The lifting arm 14 is interposed between the main frame 1 and the sash 2, such that the lifting arm 14 has a first end portion 14a connected with the carriage 30 and a second end portion 14b connected with the sash 2.

[0110] The lifting arm 14 is connected to the carriage guide 16 via the push arm 40. The push arm 40 has a third end portion 40a rotatably connected to the carriage guide 16 and a fourth end portion 40b rotatably connected to the lifting arm 14, in the shown embodiment by means of a first rivet 42i to the carriage guide 16 and a second rivet 42ii to the lifting arm 14, as FIG. 5 is shown in more detail.

[0111] The carriage 30 is attached to the spring assembly 20, which is arranged to exert a force on the carriage 30 in a state of use of the roof window 100. The carriage 30 can be uncoupled from the spring assembly 20, as FIG. 2BAs an example, this can be an advantage during installation of a roof window, in which the spring force acting on the carriage 30 can make it difficult to operate the roof window. In case the lifting device is installed in a roof window according to its intended use, the carriage 30 and the spring assembly 20 are initially in an uncoupled state. The spring assembly 20 and the carriage 30 are then coupled by opening the roof window causing the carriage 30 to slide towards the coupling device, such as the hook 21 attached to the spring comprised in the spring assembly 20. This coupling can for example be achieved by the carriage 30 comprising a coupling plate 32 for coupling the carriage 30 to the spring assembly 20. Opening the roof window causes the carriage 30 to engage with the hook 21 and once the roof window is subsequently closed, the carriage 30 will slide in a direction away from the spring assembly 20 towards the top hinge of the roof window 100 and the spring now coupled to the carriage 30 will exert a pulling force on the carriage 30 and provide a resistance against closing of the roof window.

[0112] The pulling force of the spring assembly 20 and the weight of the movable parts of the roof window 100 are preferably balanced so that the sash 2 of the roof window 100 can be positioned in an open position without being forced to close by its own weight or being forced to open the roof window 100 further by the pulling force exerted by the spring of the spring assembly 20. This balance is influenced by the inclination of the roof on which the roof window is installed. The spring in the spring assembly 20 can be adjusted to balance the roof window to a specific roof inclination. If the roof window is installed on a roof with a different inclination than the intended inclination, the spring force acting on the carriage 30 will be unbalanced with the weight of the movable parts of the roof window. In one example, the spring can exert too much force on the window, thereby forcing the window to open further. In another example, the spring can be too weak and the window will close by its own weight. In both cases, the window can be difficult to operate for a user and be potentially dangerous.

[0113] To easily adjust the roof window 100 according to the roof inclination, an adjustment system 50 can be used. The adjustment system 50 can be used to adjust the roof window for roof inclinations in the range of 15° to 60°.

[0114] FIGS. 3A-4C Embodiments of the adjustment system 50 are shown in more detail in Fig. 2. The adjustment system 50 is connected to an adjustment arm 52, which in turn is connected to other components of the lifting device 10, as will be described in further detail below.

[0115] FIG. 3AAn adjustment screw 53 is shown, having an adjustment screw shaft 53i, an adjustment screw wheel 53ii, and an adjustment screw top 53iii. In the embodiment shown, the adjustment arm 52 is a two-part component comprising a first adjustment arm 521 and a second adjustment arm 522, and is coupled to the adjustment bushing 54.

[0116] FIG. 3B The assembly of the adjustment screw 53 is shown housed between the first lift arm 141 and the second lift arm 142, and in the opening 15. FIG. 3A FIG. 3B In the embodiment shown, the adjustment system 50, comprising the adjustment screw 53, is shown housed between the first lift arm 141 and the second lift arm 142, and in the opening 15. The adjustment arm 52 has a seventh end 52a connected to the adjustment system 50 via the adjustment bushing 54. An eighth end 52b of the adjustment arm is rotatably connected to the lift arm 14, allowing the adjustment arm 52 to travel along a path in the opening 15 of the lift arm. In the embodiment shown, the opening 15 of the lift arm is arcuate, but in principle can have any shape that allows for proper movement. The adjustment screw wheel 53ii is housed in a separate opening 17 in the lift arm 14. Preferably, the adjustment screw is connected to the lift arm 14 via the adjustment screw top.

[0117] FIG. 3C The carriage arm 31 is shown, having a fifth end 31a rotatably connected to the lift arm 14, and a sixth end 31b rotatably connected to the carriage 30, not shown in the embodiment. FIG. 3C The carriage arm 31 is connected to the adjustment bushing 54. In the embodiment shown, the carriage arm 31 is a two-part component, as will be described below.

[0118] Thus, the adjustment arm 52 is arranged in the lift arm 14 between the first lift arm 141 and the second lift arm 142, and the carriage arm 31 is arranged outside of the lift arm 14.

[0119] FIGS. 4A-4C The assembly of the lift arm 14 and the carriage arm 31 in the embodiment is shown. FIGS. 3A-3C The sixth end 31b of the carriage arm 31 is shown arranged to rotate around the adjustment bushing 54, and FIG. 4B The fifth end 31a of the carriage arm 31 is shown arranged to move along the adjustment screw shaft 53i when the adjustment screw 53 is adjusted. FIG. 4C

[0120] FIG. 5 ​​A push arm 40 is shown, having a third end 40a configured for attachment to the carriage guide (not shown) and a fourth end 40b rotatably connected to the lifting arm 14. In FIG. 5 , the push arm comprises a first push arm 401 and a second push arm 402 arranged on opposite sides of the lifting arm 14. The lifting arm 14 is rotatably connected to the sash 2 (not shown) by means of a rivet 41. The connection between the lifting arm 14 and the sash 2 is shown in FIG. 8 and FIGS. 10D-10E .

[0121] The assembly of the lifting arm 14, the push arm 40, the adjustment system 50, the adjustment arm 52 and the carriage arm 31 according to one embodiment of the present utility model is shown in FIG. 6 .

[0122] Reference is now made to FIG. 7 , showing an embodiment of the carriage 30 and the push arm 40 to be arranged in the carriage guide 16. FIG. 7 The carriage in has a first front runner 701 and a second front runner 702 arranged to be slidably connected to a front rail 43a on each side of the carriage guide 16, and a rear runner 71 arranged to be slidably connected to a rear rail 43b on each side of the carriage guide 16. In this embodiment, the first front runner 701 and the second front runner 702 comprised in the front runners 70 are shown as two separate runners, but can in other embodiments be coupled to form a single front runner 70.

[0123] FIG. 8 A lifting device 10 according to the present utility model is shown, wherein the lifting arm 14 is inserted between the main frame 1 and the sash 2. The carriage guide 16 extends along a length axis in a length direction L. The lifting arm 14 also extends in the length direction L when the window is in a closed position. A height axis extends in a height direction H perpendicular to the length direction L. The height axis extends perpendicular to the panes of a roof window when the lifting device is installed in a roof window. The length axis and the height axis define a centre plane P.

[0124] Generally, the lifting arm 14 of the shown embodiment comprises a first lifting arm 141 and a second lifting arm 142 arranged symmetrically with respect to the centre plane P. Forming the lifting arm 14 as a two-part component at least, the forces exerted by the lifting arm 14 onto the centre plane P are balanced, providing an advantageous load distribution within the lifting device 10. That is, the forces resulting from the weight of the movable parts of the roof window 100 are aligned with respect to the centre plane P.

[0125] The push arms 40 comprise a first push arm 401 and a second push arm 402 arranged symmetrically with respect to the centre plane P. The carriage arms 31 comprise a first carriage arm 311 and a second carriage arm 312 arranged symmetrically with respect to the centre plane. Finally, the adjustment arms 52 comprise a first adjustment arm 521 and a second adjustment arm 522 arranged symmetrically with respect to the centre plane P and extending along the centre plane P, while the adjustment screw 53 extends in the centre plane P. The symmetrical arrangement of the components of the lifting device provides a lifting device in which forces from the panes and other movable components of the roof window are aligned with respect to the centre plane P. This ensures that the torque on the individual parts of the lifting device is minimised and makes the lifting device and the roof window as a whole stable.

[0126] Now turning to FIGS. 10A-10E , an embodiment comprising an adjustment system 50 according to the present disclosure is shown. The adjustment system 50 is shown as comprising an adjustment screw 53 arranged within the profile of the lifting arm 14 so as to be accessible via an opening in the lifting arm 14, as will be described below.

[0127] FIG. 10B It is shown how the adjustment system is adjusted by applying an external force. In this embodiment, the external force is applied to the adjustment screw wheel 53ii via the screw driver bit 60. In the embodiment shown in FIGS. 10A-10C , the lifting arm 14 is arranged to receive the screw driver bit 60 through an opening in the lifting arm 14. In the embodiment shown, the opening is provided as a space between the first lifting arm 141 and the second lifting arm 142, so that the screw driver bit 60 can be inserted from the back of the lifting arm 14. Thus, the adjustment system 50 is most easily adjusted when the roof window 100 is in the open position. The opening for such a screw driver bit can alternatively and / or additionally be arranged on the other side, such as the front, or on one or both sides of the lifting arm, e.g. via the opening 15 described above. By having an opening on the side of the lifting arm 14, the adjustment system 50 can be adjusted in both the open and closed positions of the roof window.

[0128] In FIG. 10D and FIG. 10E , it is shown how the adjustment system 50 is adjusted to change the position of the fifth end 31a of the carriage arm 31 with respect to the lifting arm 14 by moving the fifth end 31a of the carriage arm 31 along the adjustment screw 53, thereby changing the force balance between the pulling force from the spring assembly 20 and the weight of the window, so that the roof window 100 can be adjusted for different roof inclinations. Thus, the fifth end 31a of the carriage arm 31 is shown with two different positions with respect to the lifting arm 14, corresponding to the adjustment for two different roof inclinations.

[0129] FIG. 11A andFIG. 11B An enlarged detail view of the adjustment is shown in FIG. 10D and FIG. 10E The first angle a1 formed between the carriage arm 31 and the lifting arm 14 is clearly shown, and it is configured to become a second angle a2 when the adjustment system 50 is adjusted. In the embodiment shown, this is achieved by adjusting the position of the fifth end portion 31a of the carriage arm 31 by means of the adjustment system 50. The first angle a1 can be regarded as a starting angle or a predetermined angle, which typically forms part of the factory settings in the supplied state of the lifting device 10.

[0130] FIG. 12 A close-up bottom perspective view of the adjustment system is shown, in which it is clearly shown that the push arm 40 comprises indications for adjusting to different roof inclinations. In this embodiment, these indications are numerical values ranging from 15 to 60 corresponding to respective degrees. These values indicate and correspond to the desired roof inclination for which the user should adjust the lifting device 10. By moving the position of the fifth end portion of the carriage arm 31 on the adjustment screw 53 to a particular numerical value, the user is able to adjust the lifting device of the roof window to the desired roof inclination. In the embodiment shown in FIG. 11A , FIG. 11B and FIG. 12 In the embodiment shown in, the values shown on the push arm are 15, 30, 45 and 60 corresponding to roof inclinations of 15 degrees, 30 degrees, 45 degrees and 60 degrees. Furthermore, in the embodiment shown there is included a marker indicating an ascending or descending order of the numerical values. In alternative embodiments, values of roof inclinations higher or lower than those indicated in the embodiment shown can be implemented.

Claims

1. A lifting device (10) for a roof window (100), the lifting device (10) comprising: a lifting arm (14) adapted to be inserted between a main frame (1) of the roof window (100) and a secondary frame of the roof window, the lifting arm (14) having a first end (14a) rotatably connected to a carriage (30) adapted to be slidably connected to the main frame (1) in a carriage guide (16), and a second end (14b) adapted to be rotatably connected to the secondary frame, the lifting device (10) further comprising a spring assembly (20) configured to be coupled to the carriage (30), the lifting device (10) further comprising a push arm (40) having a third end (40a) rotatably connected to the carriage guide (16) and a fourth end (40b) rotatably connected to the lifting arm (14), the lifting arm (14) and the carriage guide (16) extending along a length direction (L) defining a central plane (P), the central plane (P) extending along the length direction (L) and a height direction (H) perpendicular to the length direction (L), characterized in that the lifting arm (14) comprises a first lifting arm (141) and a second lifting arm (142) arranged symmetrically with respect to the central plane (P), and a force exerted by the lifting arm (14) onto the central plane (P) is balanced.

2. The lifting device (10) according to claim 1, characterized in that the lifting arm (14) is adapted to be connected to a sash (2) forming the secondary frame of the roof window (100).

3. Lifting device (10) according to any one of claims 1 and 2, characterized in that the push arm (40) comprises a first push arm (401) and a second push arm (402) positioned on opposite sides of the lifting arm (14) and symmetrically positioned with respect to the central plane (P).

4. The lifting device (10) according to claim 1, characterized in that the lifting device (10) further comprises a carriage arm (31) connected at a fifth end (31a) to the lifting arm (14) and at a sixth end (31b) to the carriage (30).

5. The lifting device (10) according to claim 4, characterized in that the carriage arm (31) comprises a first carriage arm (311) and a second carriage arm (312) arranged symmetrically with respect to the central plane (P).

6. The lifting device (10) according to claim 4, characterized in that the lifting device (10) further comprises an adjustment system (50) comprising an adjustment screw (51) arranged in an opening of the lifting arm (14) and extending along the central plane (P), and wherein the carriage arm (31) is rotatably connected to the lifting arm (14) via the adjustment screw (51).

7. The lifting device (10) according to claim 6, characterized in that The lifting device (10) further comprises an adjustment arm (52) rotatably connected at a seventh end (52a) to the adjustment screw (51) and at an eighth end (52b) to the lifting arm (14).

8. The lifting device (10) according to claim 7, characterized in that The adjustment arm (52) comprises a first adjustment arm (521) and a second adjustment arm (522) arranged symmetrically with respect to the central plane (P).

9. Lifting device (10) according to any one of claims 7 and 8, characterized in that The adjustment arm (52) extends along the central plane (P).

10. The lifting device (10) according to claim 1, characterized in that The carriage (30) comprises at least two runners (70, 71) each slidably connected to a track (43a, 43b) in the carriage guide (16).

11. The lifting device (10) according to claim 10, characterized in that The at least two runners (70, 71) comprise a front runner (70) configured to slide in a first track (43a) located proximate a third end of the carriage guide (16) and a rear runner (71) configured to slide in a second track (43b) located proximate a fourth end of the carriage guide (16).

Images