Note: Descriptions are shown in the official language in which they were submitted.
'1'h15 W Au ~wriJ;C~I;~ JliKJIUN.
1
~~~J~ e1
- 1 -
Title: Metal fitting having a worm drive for moving a
pivotally mounted window or door leaf.
Descri~pt ion
The invention relates to a metal fitting for mov- ing
a pivotally mounted leaf of a window or door, com-
prising a drive casing which is adapted to be mounted on
the fixed frame of the window or door and in which a worm
drive, comprising a worm rotatable by means of a crank
and a worm wheel meshing with said worm, and also a lever
arm rigidly connected to said worm wheel are mounted,
said lever arm extending out of the drive casing in the
direction of the leaf and being directly or indirectly
drivingly coupled to the leaf.
Fittings of this kind are known from United States
Patent Specifications 2 635 485 and 2 732 726. Such
fittings are used in particular for opening and closing
window leaves mounted for pivoting about a vertical
axis. In these arrangements the drive casing is mounted
on the bottom horizontal member of the fixed frame, near
the pivoting axis of the leaf. In order to be able to op-
erate the worm drive conveniently by means of a crank, the
worm is mounted in the casing with its axis inclined
relative to the main plane of the casing. The axis of
rotation of the crank coupled nondetachably or detachably
to the worm then extends obliquely upwards into the room,
so that the fitting can be conveniently operated.
A disadvantage of these known fittings consists in
CA 02079682 2000-04-17
- 2 -
that they cannot be used at choice for windows mounted on
the right-hand or on the left-hand side. The drive must
be manufactured in two different models for either windows
hinged on the right-hand side or those hinged on the left-
hand side. In addition, it is a disadvantage that the
free end of the lever arm must be joined to the leaf by
means of a slide guide, which results in an unfavorable
ratio between the opening and closing forces transmissible
to the leaf and the operating stiffness of the fitting.
From United States Patent Specification 2 795 413
another fitting of this kind is known, which can be used
at choice for windows hinged on the right-hand or left-
hand side by turning the entire fitting 180° in relation
to an axis at right angles to the frame. This can be done
without structural modification of the fitting, but only
if the axis of the worm also extends at right angles to
the plane of the frame. A crank coaxially coupled to the
worm would however then have to be turned in a plane ex-
tending parallel to the plane of the frame, although turn-
ing it in that way is often prevented by an inwardly pro-
jecting window ledge or the Like. It is therefore usually
desirable to be able to turn the crank in~a plane extend-
ing at an oblique angle to the plane of the window frame.
For this purpose the known fitting is provided with a
crankpin which extends at an angle to the axis of the worm
and which is coupled to the worm by means of a bevel gear
pair. For the conversion of the fitting from right-hand
to left-hand mounting of the window it is necessary to
CA 02079682 2000-04-17
3
detach a casing part in which said crankpin and one of the
bevel gears are mounted and to reconnect it to the casing
after turning it 180°. This entails an expensive design and
complicated conversion work.
Another fitting of the kind referred to, which
can be converted from right-hand to left-hand mounting, is
know from United States Patent Specification 1 090 259. For
conversion from right-hand to left-hand mounting with this
fitting, both the lever arm and the sector-shaped worm
wheel and the worm must be detached and each of these parts
must be refitted after being turned 180°. The conversion
procedure is therefore very complicated. In addition, this
known fitting cannot be made with a crank axis extending
obliquely to the plane of the frame.
The problem underlying the invention is that of
so designing a fitting of the type indicated that it can be
converted in a very simple manner for use at choice for
window or door leaves hinged on the right-hand or left-hand
side.
According to the present invention, there is
provided, as a solution to this problem, a fitting for
moving a pivotally mounted leaf of a window or door,
comprising a drive casing (3) which is adapted to be
mounted on a fixed frame of the window or door and in which
a wore drive comprising a worm (19) rotatable by means of a
crank and a worm wheel (9) meshing with said worm, and also
a lever arm (11) detachably connected to said worm wheel to
rotate therewith are mounted, said lever arm extending out
of the drive casing (3) in the direction of the leaf and
being directly or indirectly drivingly coupled to said
leaf, wherein without changing positions in which the worm
CA 02079682 2000-04-17
3a
wheel (9) and the worm (19) are installed said lever arm
(11) is insertable into the drive casing (3) to be coupled
to the worm wheel (9) in two alternative positions which
are inverted by 180° with respect to each other.
The following embodiments to other advantageous
developments of the invention.
Preferably the two alternative positions of the
lever arm (11) are angularly symmetrical relative to a
plane of symmetry (E) extending at right angles to a plane
of the frame and through a pivoting center (M) of the worm
wheel (9) .
Preferably the lever arm (11) is pivotable over
an angular range bounded but stops and wherein a portion
(lla) of the lever arm (11), which portion extends radially
relative to the pivoting center (M), lies, in two end
positions of a pivoting range, symmetrically to the plane
of symmetry (E) extending through the pivoting center (M)
and at right angles to the frame.
Preferably the portion (lla) of the lever arm
extending radially relative to the pivoting center (M) is
followed by a portion (llc) bent over relative thereto at
an angle of about 45°.
Preferably the lever arm (11) extends through a
cutout (31) in a plate (29) adapted to be fastened to a
rabbet surface of the frame (40), the cut-out (31) having
ends forming end stops bounding a pivoting range of the
lever arm ( 11 ) .
Preferably the plate (29) is centered on the
drive casing (3) by at least one centering pin (33) and is
adjustable to different distances form the drive casing
(3) .
CA 02079682 2000-04-17
3b
As a further development of the invention the
transmission of the opening and closing forces to the leaf
is also to be improved. According to the invention this is
achieved by the following embodiments
Preferably the worm wheel (9) has a diameter that
is larger than depth of the drive casing (3) at right
angles to a plane of the frame.
Preferably the lever arm (11) has a free end
connected to the leaf (41) by means of a connecting link
(65) which is connected by pivot joints (63, 47) to the
lever arm (11) and the leaf.
Preferably the leaf (41) is mounted on the frame
(40), by means of two mounting links (51, 53) of unequal
lengths, for pivoting about a virtual pivoting axis and
wherein the connecting link (65) is articulated on the leaf
(41) at a pivot point (47) which in relation to the pivot
point (57, 61) of the two mounting links (51,53) on the
leaf is offset in the direction of the fixed frame(40).
One embodiment of the invention will be explained
mor fully with the aid of the drawings, in which:
CA 02079682 2000-04-17
- 4 -
Figure 1 is an exploded view in perspective of the
components of the fitting;
Figure 2 is a schematic plan view of the fitting
mounted on the window, with the window leaf in the open
position;
Figure 3 is a similar view to Figure 2, with the
leaf in the closed position;
Figure 4 is a schematic view of the fitting illus-
trating the two possible positions for the mounting of the
lever.
According to Figure 1, the drive casing comprises
a casing box 3 in the form of a casting and a cover S
fastenable to the casing box by screws (not shown).
A seat 6 is formed both in the casing box 3 and in the
cover 5 for a mounting pin 7, on which a worm wheel 9 and
a lever arm 11 coaxial to the latter are rotatably
mounted. By means of projections 13 embossed on the wheel
9 and engaging in corresponding openings 15 in the lever
arm .11, the latter is coupled to said wheel 9 for rotation
therewith. The lever arm 11 is an integral component con-
sisting of a disk 11a which is coaxial to the wheel 9, an
arm portion 11b projecting radially from said disk, and an
end portion 11c which is bent over at an an angle of pre-
ferably 45° to said arm portion and in whose free end a
bearing hole 17 is provided.
In the casing box 3 a worm 19 is also mounted for
rotation in a bearing 21 and meshes with and drives the
worm wheel 9. The worm 19 has a shaft journal 23 which
CA 02079682 2000-04-17
- 5 -
projects out of the casing and is suitably shaped, for ex-!,
ample as a hexagon, for coupling to a crank (not shown)
adapted to be fitted on the shaft journal 23. The axis of
the worm 19 and of the shaft journal 23 extends at an
angle, for example 30°, to the main plane of the dive
casing (that is to say to the plane of the drawing in Fig-
ure 1).
The casing box 3 is provided in the longitudinal
direction with two extensions 25 in which holes 27 are
formed to receive screws by which the drive casing can
be fastened to the face, on the room side, of the bottom
member of the fixed window frame.
The fitting also includes an angle plate 29, which
is inserted into the rabbet of the fixed frame and, in
the case of the arrangement of the screw holes shown in
Figure 1, is for example screwed fast to the rabbet sur-
face at right angles to the plane of the frame. In the
leg of the plate 29 which lies against the rabbet surface
parallel to the frame a slot 31 is formed for the passage
of the lever 11. The Length of the slot 31 is so adjusted
that the lever 11 can be pivoted over the required angular
range, that is to say the pivoting range of the lever 11
is limited, not by the casing box 3, but by the slot 31 in
the angle plate 29. The angle plate 29 is centered on the
casing box 3 by means of two centering pins 33, which are
slidably guided in corresponding holes 35 in the casing
box 3, so that the angle plate 29 can be adjusted at any
desired distance from the casing box in accordance with
_,
- 6 -
the dimensions of the frame profile in question.
Figure 2 shows the fitting mounted on a window. 40
40 designates the fixed frame and 41, the window leaf. The
drive casing 1 is mounted on the bottom horizontal member
of the fixed frame 40, on the visible surface pointing
towards the interior of the room, and is screwed in place
at the points 43. The angle plate 29 is fastened in the
rabbet 46 of the frame profile. In the profile of the
fixed frame 40 a suitable recess 45 is formed for the
passage of the centering pins 33 of the angle plate 29 and
for the lever 11. Figure 1 shows that the diameter of the
worm wheel 9 and also that of the mounting disk 11a of the
lever 11 are greater than the depth of the drive casing
1, so that the wheel 9 and the mounting disk 11 extend
into the recess 45. The lever 11 can thus have a large
pivoting angle range in relation to the drive casing 1,
and this pivoting angle range is limited only by the
length of the slot 31 in the angle plate 29.
. The leaf 41 is mounted on the top and. bottom mem-
bers of the fixed frame by means of respective pairs of
links of unequal length, only the links 51, 53 of the
bottom mounting being shown in Figure 2. The longer link
51 is mounted on the fixed frame in a pivot bearing 55
and on the leaf frame in a pivot bearing 57. The
shorter link 53 is mounted on the fixed frame in a pivot
bearing 59 and on the leaf in a pivot bearing 61. The
pivot bearings 55, 59 of the fixed frame anc! the pivot
bearings 57, 61 of the leaf are in each case preferably
CA 02079682 2000-04-17
- 7 -
situated in a common plane parallel to the plane of the
frame and that of the leaf respectively. The length of
the links 51, 53 and the distances between the pivot
bearings 55, 59 and 57, 61 are so determined that the
links 51, 53, as a four-bar linkage, control a:rypivoti~ng
movement of the leaf 41 about a virtual vertical axis of
rotation.
At the free end of the Lever 11 a connecting link
65 is mounted in a pivot bearing 63, the other end of said
link being connected to the leaf 41 in a pivot bearing 47.
In relation to the pivot bearings 57, 61 of the mounting
links 51, 53 the pivot bearing 47 is offset both in the
direction of the plane of the leaf and at right angles
thereto, that is to say it is situated nearer the bottom
edge of the leaf 41 than the pivot bearings 61, 57 and it
is offset from the common plane of the pivot bearings 57,
b1 in the direction of the inside of the leaf.
For the operation of the drive 1 by means of the
crank <not shown) fitted on the shaft journal 23, the
lever 11 is turned so that the pivot bearing b3 moves on
the circular arc 69. When the leaf is closed the fitting
is in the position shown in Figure 3, in which the mount-
ing links 51, 53 lie rectilinearly one over the other.
The lever 11 has been pivoted into its lowermost position,
that is to say to one end point of its pivoting range. As
can be seen in Figure 3, the distance Ll between the
pivoting center M of the lever 11 and the pivot bearing 57,
in which the connecting link 65 acts on the leaf 41, is
CA 02079682 2000-04-17
shorter than the sum of the length LZ between the pivot-
ing center M and the pivot bearing b3 at the end of the
lever 11 and the length of the connecting link 65 between
its pivot bearings 63 and 47. This means that in the
closed position the articulated link arrangement formed by
the lever 11 and the connecting link 65 has not yet
reached its completely extended position in relation to
the pivoting center M, so that in this position also the
torque exerted by means of the worm drive relative to the
pivoting center M is still producing a shearing force of
the link 65 in the downward direction (in Figure 3). This
means that in the closed position of the window leaf 41
the closing force exerted by means of the drive and of
the lever 11 has not yet declined to zero.
In the closed position a closing plate 71 disposed
on the leaf can engage behind a locking pin 73 on the
fixed frame.
When the worm drive 9, 19 in the drive casing 1 is
operated in the opening direction, the lever 11 is turned
in the clockwise direction (in Figure 3>. It thus exerts
a tractive force on the connecting link 65, thus producing
a torque on the Leaf 41 because of the lateral offset be-
tween the pivot bearing 47 and the pivot bearings 57, 61
of the mounting links 51, 53, so that said leaf begins to
pivot. If the opening movement is continued, the parts
finally reach the position shown in Figure 2, in which
the leaf 41 is completely open and is situated approxi-
mately at right angles to the plane of the fixed frame 40.
CA 02079682 2000-04-17
- 9 -
The leaf 41 can of course also be adjusted to any
intermediate position, and is automatically secured in
any intermediate position because of the self-Locking
action of the worm drive.
In order to convert the drive casing 1.from right-
hand to left-hand mounting, which can be done either in
the factory during manufacture or subsequently at the in-
stallation site, the cover 5 is unscrewed from the casing
box 3, the lever is removed from the wheel 9 and replaced
on the wheel 9 after being turned lgp° , so that its pro-
jections 13 engage in the reverse positions in the cutouts
15. The cover 5 is then screwed on again.
Figure 4 illustrates how the lever 11 can in this
way be installed in two different positions 11 and 11' in
the drive casing 1, the two positions 11 and 11' being
angularly symmetrical to the plane E extending through the
pivoting center M of the lever 11 and of the wheel 9 and
at right angles to the plane of the frame.
This modification of the position in which the
Lever arm is installaed is the only operation necessary
for conversion from right-hand to left-hand mounting or
vice versa. The wheel 9 and the worm 19 can remain in po-
sition, and the orientation of the entire casing 1 is also
not changed on conversion from right-hand to left-hand
mounting. The shaft journal 23 is thus directed obliquely
upwards for both right-hand and left-hand installation of
the fitting. Merely by turning the angle lever 11, for
example from the position 11 to the position 11' in Figure
2~?! ~ ~3
- 10 -
4, the effect is achieved that the starting position of "
the angle lever 11 is transposed in relation to the angular
path bounded by the slot 31. In the position 11 shown in
Figure 4 the angular path from the top end of the slot in
the angle plate 29 to the bottom end of the slot is avail-
able for the lever arm 11' for the closing of the window
leaf, while i the position 11' the reverse angular path
has to be travelled.
