Technical Field
[0001] The present invention relates to a roof window, particularly for installation in
or on a roof surface having an inclination, comprising a primary frame, at least one
secondary frame, such as a sash and/or an intermediate frame, and a lifting device
comprising an adjustment system comprised in a sledge, the lifting device further
comprising a spring assembly configured to be coupled to the sledge, and a linkage
system being rotatably connected to the sledge through the adjustment system and connected
to the secondary frame, wherein the linkage system comprises a lifting arm with a
first end rotatably connected to the adjustment system, and the adjustment system
is adapted to move the first end of the lifting arm upon activation of the adjustment
system.
Background Art
[0002] Windows for installation in an inclined roof surface may be provided in a number
of varieties and include more or less complicated operational structures to allow
opening of the sash and to fulfil other functions, such as ventilation. Such roof
windows include the type hinged at or near the centre, the top-hinged type, and finally
the roof windows that are top-hinged during normal operation but in which the sash
is able to perform a rotating movement substantially at a centre axis, either for
cleaning or for providing an alternative manner of operation. Roof windows of the
top-hinged type have a first hinge axis provided by a top hinge arrangement to provide
a first operational condition, whereas rotation of the sash in a second operational
condition is performed by means of an intermediate frame in which the sash is hinged
to provide a secondary hinge axis. Typically, one hinge of the hinge arrangement will
be located at either side of the roof window to define a substantially horizontal
hinge axis.
[0003] Examples of top-hinged windows with a second operational condition are for instance
disclosed in Applicant's
WO-A-89/10460,
EP 0 733146 B1,
EP 1 873 323 B1,
EP 2 762 665 A2, and
WO 2019101281 A1. To make it possible to rotate the window sash approximately 180° to a convenient
cleaning position, the sash structure is connected with an intermediate frame with
frame arms, which in the closed position of the window are positioned between the
upper parts of the frame and sash side members, and which during normal use of the
window as a top-hung window follow the sash side members.
[0004] Furthermore, the opening of a roof window and the force required to operate the window
is affected by the inclination of the roof in which the window is installed.
[0005] In roof windows in which the operation takes place either entirely or partially about
a hinge axis at the top, it is known to balance at least part of the weight of the
movable components by means of a lifting device. The purpose of this arrangement is
to facilitate opening the window, and the dimensions may be chosen so that a spring
can retain the top-hinged frame in equilibrium in a desired opening position.
[0006] Such a lifting device is for instance disclosed in the Applicant's
WO2019/101281 A1 where a spring assembly acts as a force balancing element to the pane-carrying frame
by operating on a lifting arm attached to the frame.
[0007] Another example of a lifting device is disclosed in the Applicant's
EP 4 390 030 A1.
[0008] Yet another example of a lifting device is shown in
DE 31 26 531 A1.
[0009] However, although the lifting device in the above example is to some extent capable
of providing the desired force balance, there is still room for improvement.
Summary of Invention
[0010] With this background it is an object of the present invention to provide a roof window
with a lifting device having an increased design flexibility allowing the desired
movement pattern and simple structure.
[0011] This is achieved with a roof window of the kind mentioned in the introduction, which
is further characterised in that the sledge is slidably connected to the primary frame
in a sledge guide.
[0012] This arrangement provides an alternative connection of the linkage system to the
sledge and a versatile solution for adjusting to different roof inclinations. Furthermore,
the linkage system has a simple structure which may minimize the cost of manufacturing
and allow easy installation and assembly of the system.
[0013] In a presently preferred embodiment, the adjustment system comprises an adjustment
screw and an adjustment bushing, and wherein the first end of the lifting arm is connected
to the adjustment screw via the adjustment bushing.
[0014] In an embodiment, the adjustment system provides a mechanism for adjusting the balance
between the weight of the pane-carrying sash with the force provided by the spring
assembly. The weight of the pane-carrying sash is at least partially carried by the
lifting arm when the roof window is in an open position and the lifting arm is arranged
such that the weight of the pane-carrying sash acts as a pulling force on the spring
in the spring assembly. The stretched spring provides a spring force towards the equilibrium
position of the spring which forces the pane-carrying sash towards an open position.
The weight carried by the lifting arm depends on the roof inclination of the roof
in which the roof window is installed. The balance between the spring force and the
force from the weight of pane-carrying sash acting on the lifting arm may therefore
change when the roof inclination is changed. The adjustment system is arranged to
adjust the balance between the force exerted by the lifting arm on the pane-carrying
sash and the weight of the pane-carrying sash. The adjustment system may be adjusted
to balance roof window for roof inclinations in the range of 15 - 65°.
[0015] In an embodiment, the adjustment screw acts as a connecting link between one or more
elements of the roof window, where one element is the lifting arm, allowing the connected
elements to be moved relative to each other when the adjustment screw is adjusted.
Generally, the adjustment screw comprises an adjustment screw shaft, an adjustment
screw head, and an adjustment screw top. In preferred embodiments, the adjustment
screw is connected to the lifting arm via the adjustment screw top and the adjustment
screw is thereby stationary relative to the lifting arm when the adjustment screw
is adjusted.
[0016] In an embodiment, one or more elements of the roof window are connected to the adjustment
screw shaft. The position of the one or more elements on the adjustment screw shaft
is arranged to be adjusted when the adjustment screw is manipulated. The adjustment
screw head is arranged to be manipulated by an external force such as the force from
a screw bit in order to rotate the adjustment screw. By adjustment of the adjustment
screw, the one or more elements connected to the adjustment screw shaft is arranged
to be moved relative to the lifting arm. This arrangement changes the balance between
the weight of the pane-carrying frame and the force exerted by the lifting arm on
the pane-carrying frame from the pull of the spring assembly.
[0017] Other presently preferred embodiments and further advantages will be apparent from
the subsequent detailed description and drawings.
Brief Description of Drawings
[0018] In the following description, embodiments of the invention will be described with
reference to the drawings, in which
Fig. 1A is a perspective view of a roof window in an embodiment according to the invention,
in a first operational condition seen from an interior side.
Fig. 1B is a perspective view of a roof window in an embodiment according to the invention,
in a first operational condition, seen from an exterior side.
Fig. 1C is a perspective view of a roof window in an embodiment according to the invention
in a second operational condition seen from an exterior side with a lifting device
according to an embodiment of the invention, and a perspective view of a lifting device
in an embodiment according to the invention.
Fig. 2 is a side view of a lifting device according to an embodiment of the invention,
showing a height direction H.
Fig. 3 is a perspective view of a lifting device according to an embodiment of the
invention.
Fig. 4 is a side view of a lifting device according to an embodiment of the invention
in a closed condition.
Fig. 5 is a side view of a lifting device according to an embodiment of the invention
in an open condition.
Fig. 6 is a side view of a lifting device according to another embodiment of the invention.
Fig. 7 is a side view of a lifting device according to another embodiment of the invention.
Description of Embodiments
[0019] In the following, embodiments of the lifting device and roof window will be described
in further detail. When referring to the Figures, the terms up, down, upwards, downwards,
top and bottom are taken relative to how the figures are displayed. A front view is
taken from the hinge and viewing towards the frame. A view from behind is therefore
taken as viewed from the frame towards the hinge. A longitudinal direction is, if
nothing else is mentioned, longitudinal along the length of a member. It is to be
understood that the arrangement shown in a horizontal orientation is not the normal
orientation as the window is installed in an inclined roof. An interior side faces
towards the interior of the building where the window is installed, while an exterior
side faces on the opposite direction towards the exterior of the building.
[0020] Referring initially to Figs 1A and 1B, a roof window 100 is shown. The roof window
100 is intended to be installed in or on an inclined roof surface (not shown).
[0021] The roof window 100 comprises a primary frame 1, a secondary frame which in the following
will be referred to as a sash 2 but which could also include an intermediate frame
connected partly to the primary frame 1, partly to a separate, glass-carrying unit
functioning as a sash, and a pane 4.
[0022] Generally, the roof window comprises a windowpane comprising at least two layers
of glass, preferably at least three layers of glass. The window may comprise an Insulating
Glazing Unit (IGU).
[0023] The primary frame 1 comprises a set of frame members including a top frame member,
two side frame members and a bottom frame member. Correspondingly, the sash 2 comprises
a set of sash members including a top sash member, two side sash members and a bottom
sash member. While the primary frame 1 and sash 2 are described as rectangular structures,
some principles of the presented concepts may be applicable to other geometrical shapes
as well.
[0024] The pane 4 comprises a number of edge portions generally associated to members of
the sash 2. An exterior pane surface 4e defines a plane of the roof window 100 in
an assembled condition of the roof window 100. The assembled condition of the roof
window 100 is achieved when main components of the primary frame 1 and sash 2 have
been assembled and the primary frame 1 and sash 2 are connected to each other, for
instance in an installed position when the roof window 100 is ready for use. Correspondingly,
an assembled condition of the sash 2 is achieved once main components of the sash
2 have been assembled, and an assembled condition of the primary frame 1 when main
components of the primary frame 1 are assembled. The term "main components" is to
be understood as encompassing primary parts of the roof window necessary to perform
all operational functions, and not including accessories or auxiliary equipment.
[0025] An interior pane surface 4i faces the interior, typically a room of a building subjacent
the roof surface in which the roof window 100 is installed.
[0026] In the embodiments shown, the sash 2 is openable relative to the primary frame 1,
to obtain one or more open positions. In such open positions, the sash 2 and pane
4 are moved out of the plane of the roof window 1. As will be described in the following,
the sash 2 is shown as being top-hung, i.e. during normal use, the sash 2 is rotated
about a substantially horizontal hinge axis at or near the top frame member and top
sash member at the top of the roof window 100. It is however conceivable to apply
some principles of the presented concepts for roof windows on different types of windows
having other opening patterns.
[0027] Further details shown in Fig 1A include an operating assembly 5, here shown as a
handle. Other operating assemblies may be present as well.
[0028] Also shown in Fig. 1B is a representative mounting bracket forming part of a plurality
of mounting brackets forming a load-transferring connection between the roof window
100 and a surrounding roof structure (not shown). Such a roof structure may include
rafters and battens, plywood or other construction materials.
[0029] An insulating frame 7 is shown. Insulation by an insulating frame is optional and
may be provided along only some of the frame members or as shown surrounding all four
frame members.
[0030] Fig. 1C shows a top-hung roof window 100. The roof window is top-hung, i.e., hinged
at the top, by means of a hinge assembly (not shown) connecting the primary frame
with the secondary frame.
[0031] The hinge assembly is configured in such a way that it allows the sash 2 to be top-hung
in a first operational condition corresponding to normal use. That is, during normal
use the sash 2 is rotated about a substantially horizontal first hinge axis at or
near the top frame member and top sash member between a closed position and an open
position.
[0032] To assist the user in opening the sash 2, a lifting device 10 is provided as will
be described in the following. Referring now also to Fig. 2, the lifting device 10
comprises a lifting arm 14 inserted between the primary frame 1 and the at least one
secondary frame, here the sash 2. The lifting arm 14 comprises a first end 14a and
a second end 14b (cf. Fig. 7).
[0033] The roof window 100 in Fig. 1C is shown with one lifting device 10 arranged between
a side member of primary frame 1 and a side member of the sash 2. Preferably, the
roof window also comprises a second lifting device between the other sash side member
and frame side member. A lifting device on each side ensures better support of the
windowpane, improves the handling of the roof window and reduces the forces required
in each lifting device.
[0034] The lifting device 10 is shown in greater details in Fig. 2. The sledge 30 of the
lifting device 10 comprises an adjustment system 50. The adjustment system slides
with the sledge in the sledge guide 16. It is conceivable that the sledge may be exchanged
with a sledge of a different kind comprising a different adjustment system. The lifting
device can in this way be tailored for specific requirements.
[0035] The sledge 30 is attached to a spring assembly 20 which is arranged to exert a force
on the sledge 30. The sledge 30 may be uncoupled from the spring assembly 20. This
may, as an example, be an advantage during installation of the roof window where a
spring force acting on the sledge 30 may make it difficult to handle the roof window.
In the cases where the lifting device is installed in the roof window according to
its intended use, the sledge 30 and the spring assembly 20 are initially in an uncoupled
state. The spring assembly 20 and the sledge 30 are then coupled by opening the roof
window resulting in the sledge 30 sliding towards a coupling device such as a hook
attached to a spring comprised in the spring assembly 20. Opening the roof window
results in the sledge 30 engaging with the hook and once the roof window is subsequently
closed, the sledge 30 will slide back in a direction away from the spring assembly
20 and the spring now coupled to the sledge 30 will exert a pulling force on the sledge
30 and provide a resistance against the closing of the roof window. The pulling force
of the spring and the weight of the roof window are preferably balanced such that
the roof window can be positioned in an open position without closing due to its own
weight or opening further due to the pull from the spring in the spring assembly.
This balance is also influenced by the inclination of the roof that the roof window
is installed in. The spring in the spring assembly 30 may be adjusted to balance the
roof window in a specific roof inclination. If the roof window is installed in a roof
with a roof inclination different than the intended inclination, the spring force
acting on the sledge will not be balanced to the weight of the movable parts of the
roof window. In one example, the spring may exert too much force on the window thereby
forcing the window to open further. In another example, the spring may be too weak,
and the window will close due to its own weight. In both cases, the window is difficult
for the user to operate and potentially hazardous. The adjustment system 50 provides
a way to easily adjust the roof window according to a roof inclination in the range
of 15 - 65°.
[0036] The adjustment system 50 is adapted to move the first end 14a of the lifting arm
14 upon activation of the adjustment system. Preferably, this movement is in a height
direction H which is substantially perpendicular to the sliding direction. Moving
the first end 14a of the lifting arm 14 in a direction substantially perpendicular
to the sliding direction has the effect of changing the height position of the first
end 14a of the lifting device 14 in the sledge guide. When the first end 14a of the
lifting arm 14 has been moved by activation of the adjustment system 50, the first
end 14a of the lifting arm 14 holds this height position until the adjustment system
50 is activated again, but the lifting arm 14 is still capable of sliding in the sledge
guide 16 via the sledge 30 regardless of the height position of the first end 14a
of the lifting arm 14 within the meaning of the adjustment range of the adjustment
system 50.
[0037] The adjustment system 50 preferably comprises an adjustment screw 51 and an adjustment
bushing 54 as shown in Fig. 3. The adjustment screw 51 may be fastened to the sledge
30 by means of an adjustment base 56. Additionally and/or alternatively, the adjustment
screw 51 penetrates the sledge 30 and sledge guide 16, as shown in Fig. 2 and 3. In
such embodiments the sledge guide 16 comprises a track 43 configured for the adjustment
screw 51, such as shown in Fig. 3.
[0038] The adjustment screw 51 may be accommodated in an opening 15 in the sledge 30 such
as shown in Figs 2 and 6. In such embodiments, the adjustment screw is configured
along the opening 15 and the adjustment bushing 54 is configured to move in the opening
15.
[0039] In other embodiments, the adjustment screw 51 is accommodated on the sledge 30 such
as on an extrusion of the sledge 30, as shown in Fig. 3.
[0040] As also shown in Fig 3, the lifting arm 14 may be connected to the adjustment bushing
54 via an adjustment arm 52. Alternatively, the lifting arm 14 may be connected directly
to the adjustment bushing 54.
[0041] In embodiments where the lifting arm 14 is connected to the adjustment bushing 54
via the adjustment arm 52, the adjustment arm 52 is preferably rotationally fixed
at a first end to the sledge 30, rotationally fixed at a second end to the lifting
arm 14, and connected to the adjustment bushing 54 at a point between the first and
second end. The adjustment arm 52 may be elongate in shape. It may alternatively have
a small angle giving it a hockey stick shape. The adjustment arm 52 may comprise a
first adjustment arm 521 and a second adjustment arm 522 configured on opposite sides
of the sledge 30.
[0042] The lifting arm 14 has a first end 14a, which is rotatably connected to the sledge
30. The lifting arm 14 is comprised in a linkage system 19 which connects the primary
frame 1 with the secondary frame 2. The lifting arm 14 is generally elongate in shape.
It may have a bend giving it the general shape of a hockey stick.
[0043] In some embodiments, the lifting arm 14 comprised in the linkage system 19 is rotationally
fixed to the secondary frame 2 via a rivet and/or axle 41. In such embodiments, the
lifting arm 14 extends from the sledge 30 in the sledge guide 16 of the primary frame
1 to the secondary frame 2, as shown in Figs 4 and 5.
[0044] In other embodiments, the linkage system 19 comprises an intermediate arm 45. The
intermediate 45 is generally elongated with a first end, a second end and a middle
portion.
[0045] The intermediate arm is connected at a first point to the sledge guide 16. This first
point may be at a first end of the intermediate arm 45. The intermediate arm is connected
at a second point to the lifting arm 14.
[0046] In some embodiments this second point is at an opposite end of the intermediate arm
45 compared to the first point. Such an embodiment is shown in Fig. 7. In such embodiments
the intermediate arm 45 is connected to the lifting arm 14 at a point between the
first end 14a and a second end 14b of the lifting arm 14. Preferably, in such embodiments
the second end 14b of the lifting arm 14 is arranged to move translationally along
the secondary frame 2. The second end 14b of the lifting arm 14 may be configured
to move translationally along the secondary frame by means of a sledge and sledge
guide arranged on the lifting arm and secondary frame, respectively. Alternatively,
the lifting arm 14 may be configured to move translationally along the secondary frame
2 by means of a wheel and wheel guide. Such a connection is illustrated in Fig. 7
where the second end 14b of the lifting arm 14 is configured to rotate and move translationally
along the secondary frame 2.
[0047] In other embodiments this second point of the intermediate arm 45 is substantially
arranged on the middle portion of the intermediate arm 45. In such embodiments the
intermediate arm 45 of the linkage system 19 is connected at a third point to the
secondary frame 2. In these embodiments, the intermediate arm 45 may be slidably connected
to the sledge guide 16 and/or slidably connected to the secondary frame 2.
[0048] The invention is not limited to the embodiments shown and de-scribed in the above,
but various modifications and combinations may be carried out.
List of reference numerals
[0049]
- 1
- primary frame
- 2
- secondary frame
- 4
- pane
- 4i
- interior pane surface
- 4e
- exterior pane surface
- 5
- operating assembly
- 7
- insulating frame
- 10
- lifting device
- 14
- lifting arm
- 14a
- first end of lifting arm
- 14b
- second end of lifting arm
- 15
- opening of lifting arm
- 16
- sledge guide
- 17
- separate opening
- 19
- linkage system
- 30
- sledge
- 40
- sash wheel
- 41
- rivet and/or axle
- 43
- track
- 50
- adjustment system
- 51
- adjustment screw
- 52
- adjustment arm
- 54
- adjustment bushing
- 56
- adjustment base
- 100
- roof window
- 521
- first adjustment arm
- 522
- second adjustment arm
- H
- height direction
1. A roof window (100), particularly for installation in or on a roof surface having
an inclination, comprising
a primary frame (1),
at least one secondary frame (2), such as a sash and/or an intermediate frame, and
a lifting device (10) comprising an adjustment system (50) comprised in a sledge (30),
the lifting device (10) further comprising a spring assembly (20) configured to be
coupled to the sledge (30), and
a linkage system (19) being rotatably connected to the sledge (30) through the adjustment
system (50), and connected to the secondary frame (2),
wherein the linkage system (19) comprises a lifting arm (14) with a first end (14a)
rotatably connected to the adjustment system (50),
and the adjustment system (50) is adapted to move the first end (14a) of the lifting
arm (14) upon activation of the adjustment system (50),
characterised in that
the sledge (30) is slidably connected to the primary frame (1) in a sledge guide (16).
2. A roof window (100) according to claim 1, wherein the adjustment system (50) comprises
an adjustment screw (51) and an adjustment bushing (54).
3. A roof window (100) according to any one of claims 1 and 2, wherein a second end (14b)
of the lifting arm (14) is rotationally connected to the secondary frame (2) via a
rivet and/or an axle (41).
4. A roof window (100) according to any one of claims 1 and 2, wherein the linkage system
(19) further comprises an intermediate arm (45) connected at a first point to the
sledge guide (16) and at a second point to the lifting arm (14).
5. A roof window (100) according to claim 4, wherein the intermediate arm (45) of the
linkage system (19) is connected at a third point to the secondary frame (2).
6. A roof window (100) according to claim 4, wherein the second end (14b) of the lifting
arm (14) is arranged to move translationally along the secondary frame (2).
7. A roof window (100) according to claim 6, wherein the second end (14b) of the lifting
arm (14) and the secondary frame (2) have a roller connection via a sash wheel (40).
8. A roof window (100) according to any one of the preceding claims, wherein the lifting
arm (14) is connected to the sledge (30) via an adjustment arm (52).
9. A roof window (100) according to any one of the preceding claims, wherein the adjustment
system (50) is adapted to move the first end (14a) of the lifting arm (14) along a
height direction (H), the height direction (H) being substantially perpendicular to
the sliding direction.
10. A roof window (100) according to any one of the preceding claims, wherein the roof
window (100) further comprises a windowpane comprising at least three layers of glass.