[0001] This invention relates to windows and in particular to windows of the type herein
referred to as turn-tilt windows comprising a fixed frame and a sash mounted thereon
by a turn and tilt mechanism for pivotal movement about a vertical axis for operation
in the turn mode and about a horizontal axis for operation in the tilt mode with the
axis of pivotal movement being selected by a control handle operably connected to
the turn and tilt mechanism.
[0002] In such windows the sash is fitted to tilt from the bottom of the frame and to turn
from the side of the frame. Operation in the tilt mode provides limited opening movement
at the top of the window sufficient for normal ventilation purposes but insufficient
to allow a person, in particular a child to fall outwards through the opening. Operation
in the turn mode provides unrestricted opening movement and allows access to both
sides of the window from the inside for cleaning purposes. The windows are therefore
particularly suited for use above ground level and in particular in high rise buildings
by allowing safe ventilation with the facility for cleaning the window from the inside.
[0003] Generally, the control handle is operable to fasten the sash in the closed position
and is rotatable from the fastened position to a first operative position for operation
of the sash in the turn mode and a second operative position for operation in the
tilt mode. The first and second operative positions are usually obtained by rotation
of the control handle through 90° and 180° respectively from the fastened position.
In addition the control handle may optionally have a third operative position which
also permits operation in the tilt mode to provide a small degree of opening movement
at the top of the window for permanent or night ventilation purposes. Where provided,
the third operative position is intermediate the first and second operative positions
and is obtained by rotation of the control handle through 135° from the fastened position.
[0004] A disadvantage of such handle operation is that the turn mode is obtained first on
rotation of the control handle and the tilt mode is only obtained after rotation of
the control handle beyond the operative position for the turn mode. Accordingly, there
is a risk, in service, of the turn mode being inadvertently selected. This presents
a serious safety hazard particularly in the case of operation of the control handle
by a child.
[0005] It is an object of the present invention to provide a turn-tilt window which overcomes
the afore-mentioned disadvantage of the known turn-tilt windows thereby providing
for safe operation by all users including children.
[0006] According to the present invention, there is provided a turn-tilt window of the kind
herein referred to wherein the control handle is operable to fasten the sash in a
closed position and is rotatable from the fastened position to a first operative position
for operation of the sash in the tilt mode and a second operative position for operation
of the sash in the turn mode, the second operative position being selected by rotation
of the control handle beyond the first operative position and, a safety device to
permit rotation of the control handle to the first operative position but restrict
rotation of the control handle to the second operative position, the safety device
being manually releasable to allow rotation of the handle to the second operative
position.
[0007] By the present invention, the normal operation of the control handle to select the
turn and tilt modes is reversed so that the tilt mode is obtained first on rotation
of the handle and a safety device is provided which prevents rotation of the handle
to obtain the turn mode until the safety device has been released. In this way the
tilt mode may be selected at all times but the turn mode may only be selected after
the safety device has been released. As a result, the window may be operated in the
tilt mode providing limited opening for normal ventilation purposes by all users but
inadvertent operation in the turn mode providing unrestricted opening with access
to both sides of the window for cleaning purposes is precluded. Consequently, the
afore-mentioned safety hazard, to children especially, resulting from unrestricted
opening of the window in the turn mode is considerably reduced.
[0008] Preferably the safety device is manually movable from a limit position in which rotation
of the control handle in a first sense to select the turn mode is precluded to a release
position in which rotation of the control handle in the first sense to select the
turn mode is permitted.
[0009] Advantageously the safety device is resiliently biassed to the limit position, for
example by a spring. In this way, the safety device is automatically re-set in the
limit position on rotation of the control handle in the opposite sense from the second
operative position.
[0010] Preferably the turn and tilt mechanism includes pivot connections between the sash
and frame for controlling opening movement in the tilt and turn modes and a drive
mechanism extending around the peripheral edge of the sash for controlling the combination
of the pivot connections for operation in the turn and tilt modes. The control handle
is coupled to the drive mechanism and, on rotation of the control handle, is operable
to displace the drive mechanism around the sash to select the required combination
of the pivot connections for operation in the turn and tilt modes.
[0011] Advantageously, the drive mechanism preferably includes means operable to prevent
rotation of the control handle when the sash is in an open position. As a result,
the user is prevented from selecting a different mode of operation when the sash is
open and the sash must first be moved to the closed position before the control handle
can be rotated. In this way, operation of the drive mechanism to obtain the required
combination of the pivot connections is ensured.
[0012] Preferably the safety device is mounted behind a face flange of the sash and is accessible
only when the sash is in an open position. In this way the safety device cannot be
released when the sash is in the closed position and the control handle must be rotated
to the first operative position to enable the sash to be opened in the tilt mode for
the safety device to be released.
[0013] Conveniently the safety device comprises a slider mounted on the sash for limited
sliding movement thereon and a fixed stud mounted on the drive mechanism for movement
therewith relative to the slider. Preferably the fixed stud is engageable with the
slider in the limit position to prevent displacement of the drive mechanism to select
the turn mode and the slider is movable to the release position to free the stud and
permit displacement of the drive mechanism to select the turn mode.
[0014] Advantageously, the engagement of the fixed stud and slider in the limit position
of the safety device corresponds to a third operative position of the control handle
intermediate the first and second operative positions in which opening movement in
the tilt mode is permitted. Preferably opening movement in the third operative position
is restricted by engagement of a lug mounted on the drive mechanism with a retainer
mounted on the frame to provide a small degree of opening movement for permanent or
night ventilation.
[0015] Preferably the slider has a bifurcated portion having a lead-in part and a narrower
tail part and the fixed stud has a shank slidable in both parts and a stud collar
slidable in the lead-in part only.
[0016] The resilient biassing acts between the slider and the sash to bias the slider to
the limit position in which the stud collar is received in the lead-in part and permits
rotation of the control handle until the stud collar abuts the slider at the end of
the lead-in part. The slider is moved to the release position by depressing against
the resilient biassing and sliding lengthwise relative to the fixed stud to locate
the stud shank in the tail part whereupon further rotation of the control handle is
permitted.
[0017] An exemplary embodiment of the invention will now be described in more detail with
reference to the accompanying drawings wherein:
FIGURE 1 is a perspective view of a window according to the present invention with
the turn and tilt mechanism superimposed;
FIGURE 2 is a perspective view of the window shown in Figure I showing operation in
the tilt mode;
FIGURE 3 is a perspective view of the window shown in Figure I showing operation in
the turn mode;
FIGURE 4 is a front view of one half of the window shown in Figure 1 showing the position
of the control handle for permanent or night ventilation;
FIGURE 5 is a side view of the window in the permanent or night ventilation position
shown in Figure 4;
FIGURE 6 is a side view, partly in section, showing the safety device in the limit
position for restricting rotation of the control handle;
FIGURE 7 is a side view similar to Figure 6 showing the safety device in the release
position for permitting rotation of the control handle;
FIGURE 8 is a view showing the relative position of the safety device in the first
operative position of the control handle;
FIGURE 9 is a view similar to Fgure 8 showing the relative position of the safety
device in the third operative position of the control handle; and
FIGURE 10 is a view similar to Figures 8 and 9 showing the relative position of the
safety device in the second operative position of the control handle.
[0018] Referring first to Figures 1 to 5 of the accompanying drawings, there is shown a
window I comprising a fixed frame 2 and a glazed sash 3 mounted thereon by a turn
and tilt mechanism 4 operable by a control handle 5 mounted on the sash 3 to select
operation of the window I in a turn mode or a tilt mode and, a releasable safety device
6 mounted on the sash 3 to prevent selection of the turn mode until the safety device
6 has been manually released.
[0019] The turn and tilt mechanism 4 includes a fixed pivot 7 and a releasable pivot 8 connecting
the bottom of the sash 3 to opposed lower corners of the frame 2 and, a scissors stay
9 connecting the top of the sash 3 to an upper corner of the frame 2 vertically above
the fixed pivot 7. The scissors stay 9 is pivotally connected to the frame 2 and may
be locked in the folded position to provide a fixed pivot.
[0020] For operation of the window 1 in the tilt mode, the releasable pivot 8 is engaged
to permit pivotal movement of the sash 3 from the bottom of the frame 2 about a horizontal
axis and, for operation of the window 1 in the turn mode, the releasable pivot 8 is
disengaged and the scissors stay 9 is locked in the folded position to provide a fixed
pivot to permit pivotal movement of the sash 3 from the side of the frame 2 about
a vertical axis.
[0021] The turn and tilt mechanism 4 further includes a drive mechanism 10 comprising respective
elongate bars 11,12,13,14 slidably mounted on each side of the sash 3 in a groove
15 extending around the peripheral edge of the sash 3 with the adjacent ends of the
bars on adjoining sides of the sash 3 being connected at three comers of the sash
3 by flexible strips 16,17,18 for transmitting the drive to successive bars around
the sash 3.
[0022] The bars 11,12,13,14 are retained in the groove 15 by a cover plate designated 19,20,21,22
and are provided with one or more locking members 23, for example bolts, rollers or
the like, which project outwardly through slots 24 in the overlying cover plate for
releasable engagement with fixed keepers 25 on the frame 2 to fasten the sash 3 in
a closed position. The drive mechanism 10 is concealed behind a face flange 26 of
the sash 3 and is not visible when the sash 3 is closed thereby providing a neat finish
and preventing tampering with the drive mechanism 10.
[0023] The control handle 5 is coupled to the drive mechanism 10 by a rack and pinion.device
40 for converting rotary movement of the control handle 5 into linear displacement
of the bars 11,12,13,14 around the sash 3 to disengage the locking members 23 from
the keepers 25 and select the required combination of the pivots 7,8 and scissors
stay 9 for operation of the window I in the turn and tilt modes.
[0024] The control handle 5 is rotatable from the fastened position shown in Figure 1 in
which the sash 3 is closed to first and second operative positions in which the sash
3 may be opened in the tilt mode and the turn mode respectively. The first and second
operative positions correspond to rotation of the control handle 5 through 90° and
180° respectively from the fastened position.
[0025] In the first operative position of the control handle 5 shown in Figure 2, opening
movement of the sash 3 in the tilt mode is controlled by the scissors stay 9 and the
full extension of the stay 9 is such as to provide an opening at the top of the window
sufficient for normal ventilation purposes but insufficient for a person, especially
a child, to pass through the opening.
[0026] In the second operative position of the control handle 5 shown in Figure 3, the sash
3 is free to open inwards in the turn mode providing access to both sides of the sash
3 to facilitate cleaning and a wide opening through which a person may pass to facilitate
escape in an emergency, e.g. in a fire.
[0027] In addition to rotation to the first and second operative positions, the control
handle 5 is rotatable to a third operative position, intermediate the first and second
operative positions in which the sash 3 may also be opened in the tilt mode. The third
operative position corresponds to rotation of the control handle 5 through 135° from
the fastened position.
[0028] In the third operative position of the control handle 5 shown in Figures 4 and 5,
opening movement of the sash 3 in the tilt mode is limited by the engagement of a
lug 27 mounted on the drive mechanism 10 in a retainer 28 mounted on an upper comer
of the frame 2 vertically above the releasable pivot 8. The retention of the lug 27
in the retainer 28 enables the sash 3 to be opened a safe small amount for permanent
or night ventilation purposes.
[0029] The drive mechanism 10 also includes means - (not shown) to prevent rotation of the
control handle 5 when the sash 3 is in an open position and thereby prevent the user
selecting a different mode of operation when the window I is open. Such means may
be of any known type and ensures that the required combination of the pivots 7,8 and
scissors stay 9 for the turn and tilt modes is always obtained. Thus, it will be understood
that, if the window I is open in the turn mode shown in Figure 3 and the control handle
5 is rotated to the first operative position shown in Figure 2 for operation in the
tilt mode, the scissors stay 9 would be released but the releasable pivot 8 would
not be engaged on the frame 2 and consequently the window 1 would fall inwards placing
a high strain on the scissors stay 9. A similar result would also be obtained if the
control handle 5 was rotated to select the turn mode while the sash 3 is open in the
tilt mode.
[0030] Referring now to Figures 6 and 7, the safety device 6 for preventing selection of
the turn mode until the safety device 6 has been released is shown and comprises a
slider 29 and a fixed stud 30 mounted on the side of the sash 3 adjacent to the upper
corner of the frame 2 above the releasable pivot 8. The safety device 6 is concealed
behind the face flange 26 of the sash 3 and is not visible or accessible when the
sash 3 is closed thereby preventing tampering with the safety device 6.
[0031] The slider 29 is mounted on the cover plate 20 for limited sliding movement lengthwise
of the cover plate 20 by means of a headed rivet 31 fixed to the cover plate 20 and
extending through a slot 32 in the slider 29. The fixed stud 30 is mounted on the
underlying bar 12 of the drive mechanism 10 and projects outwards through an elongate
opening 33 in the cover plate 20 for reception in a bifurcated portion 34 of the slider
29. The bifurcated portion 34 is in two parts having a wide lead-in part 35 and a
narrow tail part 36. The stud 30 has a shank 37 slidable in both the lead-in and tail
parts
"35 and 36 respectively of the bifurcated portion 34 of the slider 29 and, a collar
38 is provided on the shank 37 which is slidable in the lead-in part 35 only.
[0032] A spring 39 mounted on the rivet 31 acts between the cover plate 20 and the underside
of the slider 29 to bias the slider 29 to a limit-position shown in Figure 6 in which
the stud collar 38 is received in the lead-in part 35. The slider 29 is manually movable
to a release position shown in Figure 7 in which the stud shank 37 is received in
the narrow tail part 36 of the bifurcated portion 34 by depressing the slider 29 against
the bias of spring 39' to raise the bifurcated portion 34 above the stud collar 38
and sliding the slider 29 towards the stud 30.
[0033] Referring now to Figures 8,9 and 10, operation of the safety device 6 will now be
described in conjunction with the operation of the control handle 5 to select the
operation of the window 1 in the tilt and turn modes as previously described. In Figures
8,9 and 10 the fastened position of the control handle 5 is shown in dotted lines
and the operative positions of the control handle 5 are shown in full lines.
[0034] In the fastened position of the control handle 5, the safety device 6 is in the limit
position with the stud collar 38 received in the lead-in part 35 of the bifurcated
portion 34 of the slider 29. On clockwise rotation of the control handle 5 from the
fastened position, the drive mechanism 10 is actuated and the bar 12 of the drive
mechanism and the stud 30 mounted thereon are displaced relative to the slider 29
causing the stud collar 38 to move along the lead-in part 35 towards the tail part
36 of the bifurcated portion 34. As shown in Figures 8 and 9 such rotation is permitted
up to 135° so that both the first and third operative positions of the control handle
5 for operation of the window I in the tilt mode for normal and permanent or night
ventilation may be freely selected without hindrance from the safety device 6. However,
as shown in Figure 9, when the control handle 5 reaches the third operative position,
the stud collar 38 is at the end of the lead-in part 35 and further displacement of
the stud 30 relative to the slider 29 is prevented. As a result, further displacement
of the bar 12 of the drive mechanism 10 is prevented and rotation of the control handle
5 to the second operative position to select operation in the turn mode is prevented
until the safety device 6 has been manually released.
[0035] In order to select operation in the turn mode, it is necessary to rotate the control
handle 5 to the first operative position, open the sash 3 in the tilt mode to gain
access to the safety device 6, release the safety device 6 as described so that the
stud shank 37 is located in the tail part 36 of the bifurcated portion 34 of the slider
29 and close the sash 3 whereupon the control handle 5 may be rotated to the second
operative position as shown in Figure 10.
[0036] If the control handle 5 is subsequently rotated counter-clockwise from the second
operative position, the stud 30 will again be displaced relative to the slider 29
causing the stud shank 37 to move along the tail part 36 towards the lead-in part
35 of the bifurcated portion 34 of the slider 29. When the control handle 5 reaches
the third operative position, the stud 30 is again located in the lead-in part 35
and the slider 29, under the bias of spring 39, positions the stud collar 38 in the
lead-in part 35 thereby automatically re-setting the safety device 6 in the limit
position and preventing re-selection of the turn mode until the safety device 6 has
again been released.
[0037] It will be apparent from the foregoing description that by reversing the operative
positions of the control handle 5 for selecting operation in the turn and tilt modes
and providing a manually releasable safety device 6 which prevents selection of the
turn mode until the safety device 6 has been released, inadvertent selection of the
turn mode, especially by a child, is precluded. In particular, it is extremely unlikely
that the sequence of operations required to select the turn mode including first selecting
the tilt mode would be achieved by a child.
[0038] The invention is not limited to the embodiment above described, for example while
a drive mechanism consisting of elongate bars positioned along the sides of the sash
and connected by flexible corner strips has been described, other known constructions
of drive mechanisms including a length of wire extending around the sash to which
the associated elements are secured may be used.
[0039] Also the provision of a third operative position of the control handle intermediate
the first and second operative positions for a permanent or night ventilation facility
as above-described is optional and may be omitted. If the third operative position
is omitted, the engagement of the stud and slider to prevent rotation of the control
handle to select the turn mode may be arranged to correspond to the first operative
position of the control handle.
[0040] The angular separation of the various operative positions of the control handle above-described
is exemplary and may readily be altered as required to suit any given application.
[0041] The control handle may be rotatable in the counterclockwise direction from the fastened
position to select the operation in the tilt and turn modes.
[0042] The safety device may be mounted on the sash at different positions, for example
on the top of the sash.
1. A turn-tilt window (1) comprising a sash (3) mounted on a fixed frame (2) by a
turn and tilt mechanism (4) including pivot means (7,8,9) and a drive mechanism (10)
operable by a control handle (5) to select combinations of the pivot means - (7,8,9)
for pivotal movement of the sash (3) about a vertical axis in the turn mode and about
a horizontal axis in the tilt mode characterised in that the control handle (5) is
rotatable from a fastened position for securing the sash (3) closed to a first operative
position for operation of the sash (3) in the tilt mode and a second operative position
for operation of the sash (3) in the turn mode, the second operative position being
selected by rotation of the control handle (5) beyond the first operative position
and, a safety device (6) to permit rotation of the control handle (5) to the first
operative position but restrict rotation of the control handle (5) to the second operative
position, the safety device (6) being manually releasable to allow rotation of the
control handle (5) to the second operative position.
2. A window according to claim I characterised in that the drive mechanism (10) is
mounted for limited sliding movement around the peripheral edge of the sash (3) and
the safety device (6) comprises a first part (29) on the sash (3) for engagement with
and disengagement from a second part (30) on the drive mechanism (10) to prevent and
permit respectively sliding movement of the drive mechanism (10) to select the turn
mode.
3. A window according to claim 2 characterised in that the first part (29) is resiliently
biassed to a limit position for engagement with the second part (30) and is manually
movable against the resilient biassing to a release position for disengagement from
the second part (30).
4. A window according to claim 3 characterised in that the first part (29) comprises
a slider (29) having a bifurcated portion (34) and the second part - (30) comprises
a stud (30) received in the bifurcated portion (34).
5. A window according to claim 4 characterised in that the bifurcated portion (34)
has a lead-in part (35) and a narrower tail part (36) and the stud (30) has a collar
(38) slidable in the lead-in part (35) in the limit position of the slider (29) and
a shank (37) slidable in the tail part (36) in the release position of the slider
(29).
6. A window according to claim 5 characterised in that the slider (29) is mounted
for limited sliding movement on the sash (3) for positioning the shank (37) in the
tail part (36) in the release position of the slider (29).
7. A window according to any one of claims 2 to 6 characterised in that the engagement
of the first and second parts (29,30) of the safety device (6) 25 corresponds to the
first operative position of the control handle (5).
8. A window according to any one of claims 2 to 6 characterised in that the engagement
of the first and second parts (29,30) of the safety device (6) corresponds to a third
operative position of the control handle (5) intermediate the first and second operative
positions in which operation of the sash -
(3) in the tilt mode is permitted and opening movement of the sash (3) is limited
by the engagement- of respective formations (27,28) on the drive mechanism (10) and
fixed frame (2).
9. A window according to any one of the preceding claims characterised in that the
safety device (6) is accessible only when the sash (3) is open.
10. A window according to any one of the preceding claims characterised in that the
control handle - (5) is rotatable only when the sash (3) is closed.