[0001] The present invention relates to a drive unit for bottom-hung or tilt and turn window
frames, in particular for metal frames.
[0002] At present, the above-mentioned bottom-hung window frames comprise a mobile frame
hinged to the lower crosspiece of a fixed frame and a control unit for opening and
closing the mobile frame.
[0003] Between the fixed and mobile frames there are also means for guiding and for the
stable positioning of the mobile frame, designed to allow the correct movement of
the mobile frame between the closed and open positions, that is to say, at a preset
angle to the fixed frame.
[0004] Said means comprise one or two tie rods (according to the size of the frame), each
pivoting at a first end in a channel in the section forming an upright of the fixed
frame (by means of a suitably shaped rotary tie rod connecting pin), and at the other
end at a slide which is slidably connected in a channel in a corresponding upright
of the mobile frame.
[0005] Therefore, the tie rod follows the opening and closing movement of the mobile frame
thanks to the rotation allowed by the first fixed pivot on the fixed frame and by
the sliding action of the slide along the channel in the mobile frame, thanks to the
second pivot point.
[0006] The maximum opening angle possible for the mobile frame is normally given by an end
of stroke block fixed in the channel in the mobile frame, which stops the above-mentioned
slide during mobile frame opening.
[0007] Another structural addition of these guide and positioning means consists of means
for releasing the slide or rotation pin so as to achieve complete rotation of the
mobile frame, to allow the glass on the outside of the mobile frame to be cleaned.
[0008] However, with a frame structured in this way it is impossible to correctly control
the mobile frame opening speed, that is to say, the sliding action of the slide in
the channel in the mobile frame, with consequent continuous stresses on all of the
parts of which the frame consists. Over time, this can all lead to movement of the
end of stroke block in the channel and the breakage of drive elements.
[0009] In an attempt to overcome such disadvantages, some devices have been developed which
involve the use of screw means acting directly on the slide and designed to allow
expansion of the slide transversal dimension, so as to achieve greater friction during
mobile frame sliding.
[0010] This device allows, on one hand, a more controlled frame descent, but on the other
hand it makes it more difficult for the user to close the frame, since the resistance
of the slide is equal in both sliding directions. In addition, it must be remembered
that such solutions require frequent adjustments.
[0011] The aim of the present invention is, therefore, to overcome the above-mentioned disadvantages
by providing a drive unit for bottom-hung windows which has an extremely simple structure
and with the possibility of gradual control of both the mobile frame descent and the
mobile frame ascent and closing without the addition of any structural elements compared
to conventional drive units.
[0012] Accordingly, the present invention provides a drive unit for bottom-hung windows
of the type comprising a fixed frame with a crosspiece to which a mobile frame is
hinged, the latter moving between a closed position, in contact with the fixed frame,
and an open position, at an angle to the fixed frame. Between the fixed and mobile
frames there are drive means for moving the mobile frame between the closed position
and the open position. The drive means comprise at least one rod, its first end pivoting
at a first channel in a fixed frame upright and the other end pivoting at a slide
which slides, by means of an internal body, in a second channel in a mobile frame
upright. At least one end portion of the internal body of the slide at the point where
it connects to the rod has a transversal dimension that is less than the transversal
dimension of the second channel so as to allow the slide to rock inside the second
channel. This rocking by the slide allows a slowing in the movement of the mobile
frame from the closed position to the open position.
[0013] The technical features of the present invention, in accordance with the above-mentioned
aims, are set out in the claims herein and the advantages more clearly illustrated
in the detailed description which follows, with reference to the accompanying drawings,
which illustrate a preferred embodiment of the invention without limiting the scope
of the inventive concept, and in which:
- Figure 1 is a perspective view with some parts cut away to better illustrate others,
of a part of a bottom-hung window frame fitted with a drive unit according to the
present invention;
- Figure 2 is a view from A in Figure 1 of a detail of the drive unit illustrated in
Figure 1;
- Figure 3 is a view from B in Figure 1 of another detail of the drive unit illustrated
in Figure 1;
- Figure 4 is an exploded perspective view of the drive unit illustrated in the previous
figures;
- Figure 5 is a longitudinal section, with some parts cut away to better illustrate
others, of a detail showing a slide of the drive unit, illustrated in the previous
figures;
- Figures 6 and 7 are schematic front views with some parts cut away to better illustrate
others of two different configurations of the slide illustrated in Figure 5 applied
to a mobile frame;
- Figure 8 is a top plan view with some parts cut away to better illustrate others,
of an alternative embodiment of the slide illustrated in the previous figures;
- Figure 9 is a longitudinal section with some parts cut away to better illustrate others,
of the slide illustrated in Figure 8;
- Figure 10 is a cross-section through line X - X shown in Figure 8.
[0014] With reference to the accompanying drawings, and in particular with reference to
Figure 1, the drive unit in question is used for bottom-hung window frames.
[0015] These bottom-hung frames, labelled 101, comprise a fixed frame 1 to whose crosspiece
1a a mobile frame 2 is hinged at Y, the mobile frame moving between a closed position
(not illustrated), in which it makes contact with the fixed frame 1, and an open position,
in which it is set at an angle α to the fixed frame 1 (see Figure 1).
[0016] These movements by the mobile frame 2 are made possible by drive means which are
not illustrated, being of the known type and not strictly part of the present invention.
[0017] Between the fixed frame 1 and the mobile frame 2 there are also drive means 3 which
move the mobile frame 2 from the closed position to the open position and vice versa.
[0018] As illustrated in Figures 2, 3 and 4, the drive means 3 may comprise (in a minimum
configuration for small window frames) at least one rod 4, its first end pivoting
in a first channel 5 of an upright 1b of the fixed frame 1 and the second end pivoting
at a slide 6 which slides, by means of a suitably shaped internal body 7, in a second
channel 8 of an upright 2a of the mobile frame 2.
[0019] These window frames normally include two units consisting of the above-mentioned
elements and positioned on the two uprights of the fixed frame 1 and the mobile frame
2.
[0020] As is clearly illustrated in Figure 5, at least one end portion 7a of the internal
body 7 of the slide 6 at the point D of connection with the rod 4, has a transversal
dimension T which is less than the transversal dimension T1 of the second channel
8. In this way, the slide 6 rocks inside the second channel 8 (see arrow F1 in Figure
6).
[0021] This rocking allows the control, that is to say slowing, of the mobile frame 2 stroke
as it moves from the closed position to the open position.
[0022] To allow this type of controlled movement, the slide 6 also comprises means 9 which
lock the slide 6 in and release it from the second channel 8, clearly illustrated
in Figure 4. Said locking and release means 9 are used to allow the mobile frame 2
to rotate through 180° to allow total cleaning of the external part of the mobile
frame 2.
[0023] In practice, the locking means 9 form a second pivot point F on the slide 6, offset
relative to the point D of connection to the rod 4, and about which the slide 6 rocks.
[0024] In Figure 4 the locking means 9 comprise a pin 10 attached to the slide 6. The pin
10 has two opposite projections 10a and 10b (forming a sort of cam) and is mobile
(see arrow F2), manually and using a special manual grip element 10c, between a position
in which the slide 6 is locked, in which the projections 10a and 10b project from
the transversal dimension T of the slide 6 and are engaged in the second channel 8,
and a position in which the slide 6 is released, turned through an angle E relative
to the first position, in which the projections 10a and 10b are within the transversal
dimension T of the slide 6, allowing its release from the second channel 8.
[0025] As is also illustrated in Figures 8 and 10, the above-mentioned manual grip element
10c (illustrated with a dashed line) is partially housed in a lowered non-operating
position, in a slot 100 in a surface of the slide 6, so as to stabilise the grip element
10c (consisting of a spring) and prevent its unwanted rotation.
[0026] Looking more closely at the technical details, the internal body 7 also forms a mobile
frame 2 end of stroke element, upon reaching the angle α, at a position in which it
is at the maximum angle to the second channel 8 (again see Figure 6) and allowed by
a stable contact of two opposite end points of the internal body 7 on the second channel
8.
[0027] The rocking of the whole internal body 7 is caused by its particular configuration,
with a taper extending towards the outer edge of the internal body 7, at the portion
7a next to the point D of connection to the rod 4.
[0028] As illustrated in Figure 9, the internal body 7 has a portion 7h of one of its sides
that is at an angle β to the inside and extends from the second pivot point F towards
a more outer end of the internal body 7 at the portion next to the point D of connection
to the rod 4 in such a way as to confer an asymmetrical profile on a part of the internal
body 7. The remaining sides of the internal body 7 are completely straight.
[0029] In an alternative embodiment illustrated in Figure 5, the internal body 7 has, without
interruption, the first, end portion 7a tapered and extending towards the outside
of the internal body 7, at the point D of connection to the rod 4, a second, straight
intermediate portion 7b, at the above-mentioned second pivot point F, and a third,
end portion 7c which is tapered and again extends towards the outside of the internal
body 7. This internal body 7 external profile architecture allows not just slowing
of the stroke and locking at the preset angle, but also slide 6 realignment (see Figure
7) relative to the second channel 8 when the mobile frame 2 moves from the open position
to the closed position.
[0030] Figure 5 shows by way of example and without limiting the scope of the present invention,
the tapered third, end portion 7c with an extension R1 shorter than the extension
of the first tapered end portion 7a.
[0031] The second, straight intermediate portion 7b also has a transversal dimension T2
which is less than the transversal dimension T1 of the second channel 8.
[0032] The drive unit structured in this way functions as follows, starting with a closed
frame configuration.
[0033] Mobile frame 2 opening causes the rod 4 to push the slide 6 (see arrow F3 in Figure
6), and is designed to allow the slide 6 to rotate or rock about the pivot point F
in the second channel 8 (see arrow F1). The rotation is accentuated by the fact that
the pivot point F and the point D of connection to the rod 4 are distanced, that is
to say, offset from one another.
[0034] During the slide 6 upstroke (see arrow F4), this angled position of the internal
body 7 of the slide 6 in the second channel 8 slows the mobile frame 2 descent, partly
thanks to the friction generated both by the angled position and by the type of material
used to make the body 7 (normally, but without limiting the scope of the present invention,
a synthetic plastic material).
[0035] The rod 4 maximum extension, together with the maximum angle reached by the internal
body 7 in the second channel 8 stops the opening movement of the mobile frame 2 when
it reaches the angle α.
[0036] During mobile frame 2 closing, the upward thrust applied by the user is discharged
mostly at the pivot point F (see arrow F5 in Figure 7), since the rod 4 is, in this
case, a passive closing element and allows a simple realignment counter-thrust (see
arrow F6). This situation results in a counter-rotation of the body 7 (see arrow F7)
until the body 7 is substantially realigned with the second channel 8, with consequent
rapid downward sliding (see arrow F8) by the body and rapid closing of the mobile
frame 2.
[0037] A unit structured in this way fulfils the preset aims thanks to an extremely simple
configuration of the elements, which is rational in construction terms and does not
require any additional end of stroke elements in the mobile frame.
[0038] The special shape of the slide internal body allows an extremely precise control
of the frame movement, that is to say, substantially automatic slowing of the mobile
frame descent and, in contrast, allows rapid upward sliding during the closing stage
without any special adjustments on the slide.
[0039] The invention described can be subject to modifications and variations without thereby
departing from the scope of the inventive concept. Moreover, all the details of the
invention may be substituted by technically equivalent elements.
1. A drive unit for bottom-hung window frames of the type comprising a fixed frame (1)
with a mobile frame (2) hinged to its crosspiece (1a) at (Y), the mobile frame (2)
moving between a closed position, in contact with the fixed frame (1), and an open
position, at an angle (α) to the fixed frame (1); between the fixed frame (1) and
the mobile frame (2) there being drive means (3) which move the mobile frame (2) between
the closed position and the open position and vice versa, the means comprising at
least one rod (4), its first end pivoting at a first channel (5) of an upright (1b)
of the fixed frame (1), the other end pivoting at a slide (6), sliding by means of
an internal body (7) in a second channel (8) of an upright (2a) of the mobile frame
(2), the drive unit being characterised in that at least one end portion (7a) of the internal body (7) of the slide (6), at the point
(D) of connection to the rod (4), has a transversal dimension (T) which is less than
the transversal dimension (T1) of the second channel (8), allowing the slide (6) to
rock inside the second channel (8); the rocking being designed to allow a slowing
of the mobile frame (2) movement from the closed position to the open position.
2. The unit according to claim 1, characterised in that the slide (6) comprises means (9) for locking the slide (6) in and releasing it from
the second channel (8), designed to form a second pivot point (F) on the slide (6),
offset relative to the point (D) of connection to the rod (4), and about which the
slide (6) rocks.
3. The unit according to claim 1, characterised in that the internal body (7) forms a mobile frame (2) end of stroke element, when the frame
reaches the angle (α), at the internal body (7) maximum angle to the second channel
(8) and defined by a stable contact of two opposite end points of the internal body
(7) on the second channel (8).
4. The unit according to claim 1, characterised in that the internal body (7) has a taper extending towards the outer edge of the internal
body (7), at the portion (7a) close to the point (D) of connection to the rod (4).
5. The unit according to claim 1, characterised in that the internal body (7) has a portion (7h) of one side that is at an angle (β) to the
inside and extends from the second pivot point (F) and towards a more outer end of
the internal body (7) at the portion close to the point (D) of connection to the rod
(4) in such a way as to confer an asymmetrical profile on a part of the internal body
(7).
6. The unit according to claim 1, characterised in that the internal body (7) has, without interruption, a first, end portion (7a) that is
tapered and extends towards the outside of the internal body (7), at the point (D)
of connection to the rod (4) and a second, intermediate portion (7b), that is straight,
at a second pivot point (F).
7. The unit according to claim 1, characterised in that the internal body (7) has, without interruption, a first, end portion (7a) that is
tapered and extends towards the outside of the internal body (7), at the point (D)
of connection to the rod (4), a second, intermediate portion (7b), that is straight,
at a second pivot point (F), and a third, end portion (7c), that is tapered and extends
towards the outside of the internal body (7), allowing slide (6) realignment relative
to the second channel (8) when the mobile frame (2) moves from the open position to
the closed position.
8. The unit according to claim 6, characterised in that the tapered third end portion (7c) has an extension (R1) which is shorter than the
extension (R) of the tapered first end portion (7a).
9. The unit according to claim 6, characterised in that the second, straight intermediate portion (7b) has a transversal dimension (T2) which
is less than the transversal dimension (T1) of the second channel (8).
10. The unit according to claim 2, characterised in that the locking means (9) comprise a pin (10) attached to the slide (6); the pin (10)
having two opposite projections (10a, 10b) which are manually mobile between a position
in which the slide (6) is locked, in which the projections (10a, 10b) project from
the transversal dimension (T) of the slide (6) and are engaged in the second channel
(8), and a position in which the slide (6) is released, turned through an angle (E)
relative to the first position, in which the projections (10a, 10b) are within the
transversal dimension (T) of the slide (6).
11. The unit according to claim 10, characterised in that the pin (10) is attached to a manual grip element (10c) which is partially housed,
in a lowered non-operating position, in a slot (100) in a surface of the slide (6),
stabilising the grip element (10c) and preventing its unwanted rotation.