Note: Descriptions are shown in the official language in which they were submitted.
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WINDOW OPERATING MECHANISM
FIELD OF THE INVENTION
This invention relates to a window operating mechanism and in particular
to a mechanism for operating a casement window.
DESCRIPTION OF RELATED ART
As described in the Alain Clavet US Patent Application 2004/0216381,
publlished November 4, 2004, casement windows have become increasingly
popular over the past several years. Consequently, there has been a
concomitant development of mechanisms for operating such windows.
Examples of operating mechanisms for casement windows are described in a fair
volume of patent literature such as CA1,301,202, issued to Douglas A. Nolte et
al
on May 19, 1992, US 2,686,669, issued to R.O. Johnson on August 17, 1954;
US 3,044,311, issued to G.W. Gagnon on July 17, 1962; US 4,301,662, issued
to F.L. Dusmoor on November 24, 1981; US 4,840,075 issued to D.G. Tucker on
June 20, 1989; 4,938,086, issued to Douglas A. Nolte et al on July 3, 1990;
6,634,141, issued to Todd A. Anderson et al on October 21, 2003, and
6,672,010, issued to Steven A. Gledhill et al on January 6, 2004.
Casement windows are constructed to be right or left opening, i.e. hinges
are mounted on the left or right side of the window opening. The operating
mechanisms provided with such windows are adapted to open a window in one
direction only, i.e. right or left opening. In general, the mechanisms include
a
handle for rotating a worn shaft, which in turn rotates at least one gear and
a
crarik arm to open and close a window. While the elements of the right and
left
opening mechanisms may be the same, it is necessary to assemble the
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elenients in a different manner to suit the direction of opening. Various
attempts
have been made to make a universal operating mechanism which can be used to
open a window in either direction without changes to the mechanism. Existing
mechanisms of this type are somewhat complicated and, as mentioned above,
may require different assembly when being installed in a window.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to provide a casement window
operating mechanism, which, while being relatively simple, can be used to open
a window in either direction.
Another object of the invention is to provide a window operating
mechanism which is easily converted from a one arm to a two arm mechanism.
Accordingly, the invention relates to a casement window operating
mechanism comprising:
a housing for mounting on the interior of a casement window frame;
a base for mounting in an opening in a casement window, the housing
covering a portion of the base extending out of the window frame;
a crank arm having a first end rotatable on the center of said base
extending out of an exterior end of said housing for rotatable attachment to a
window sash;
a worm rotatable in said housing meshing with said crank arm and
adapted to rotate said crank arm in either direction;
teeth on said first end of the crank arm defining a major portion of a circle
meshing with said worm, whereby rotation of said gear causes a corresponding
rotation of said crank arm to open or close the window in a right or left
direction,
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depending upon which side of the window sash the crank arm is connected.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described hereinafter in greater detail with reference to
the accompanying drawings, which illustrate a preferred embodiment of the
invention, and wherein:
Figures 1 and 2 are isometric views of a casement window operating
mechanism in accordance with the invention as viewed from above;
Figure 3 is an isometric view of the mechanism of Figs. 1 and 2 as viewed
from below;
Figure 4 is a partly exploded isometric view of the mechanism of Figs. 1 to
3;
Figures 6 and 7 are schematic, isometric views of the bottom portion of a
right opening window incorporating the mechanism of Figs. I to 5; and
Figures 8 and 9 are schematic, isometric views of the bottom portion of a
left opening window incorporating the mechanism of Figs. 1 to 5.
DETAILED DESCRIPTION OF THE INVENTION
Referring to Figs. 1 to 4, the basic elements of the window operating
mechanism include a base 1, a crank arm 2 rotatably mounted on the base 1, a
worm 3 for rotating the crank arm 2, a housing 4 rotatable supporting the worm
3,
a cover 5 on the housing 4 and a crank handle assembly 6 for rotating the worm
3.
The base 1 is a one-piece casting including a flat, outer, bottom ledge 8
having a plurality of holes 9 therein for receiving screws (not shown). A
large
number of holes 9 are provided, because the base 1 is often mounted in a
plastic
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frarrie which does not hold screws as well as wooden frames. A generally U-
shaped notch 10 in the center of the ledge 8 is designed to receive one end 12
of
a sliding arm 13 the function of which is described in greater detail below.
The
end 12 of the arm 13 is pivotably connected to the raised center 14 of a small
bar
15 which is mounted in a recess 16 in the bottom center of the ledge 8.
When the bar 15 is mounted in the recess 16, the top of the raised center
14 is in the same plane as the top surface of the ledge 8. In use, a pin 17 on
the
Mter end of the arm 13 slides in a conventional track (not shown) mounted on
the bottom of a window sash 18. A shoulder 20 (Figs. 1 and 2) extends upwardly
froni the end of the base 1 for limiting movement of the base into an opening
(not
shown) through the bottom 21 of the window frame 22 (Figs. 6 to 9) when
mounting the mechanism in a window.
The crank arm 2 is defined by pivotally interconnected outer and inner
links 24 and 25. The free end of the outer link 24 is pivotally connected to
the
bottom corner 26 of the window sash 18 on the hinge side of the window. The
large circular end 27 of the inner link 25 is rotatably mounted on a pin 28
(Figs. 1,
2 and 5) in the base 1. Teeth on the end 27 of the crank arm 2 mesh with the
included worm 3 so that the crank arm 2 rotates around the axis of the pin 28
when the worm 3 turns. The worm 3 is rotatably mounted on a hub 29 in a
housing 4 and extends into a trough 31 on the teeth 30 on the crank arm 2
extend through an opening defined by notches 33 and 34 in the top of the base
1
and the bottom of the housing 4, respectively. The top end 35 of the shaft of
the
worm 3 includes longitudinally extending spines 36 for connecting the worm to
the crank handle 6.
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The housing 4 includes a recess 38 in the bottom thereof for
accommodating the circular end 27 of the crank arm 2. A fence 40 extends
around the sides and top of the inner end of the housing 4. When mounting the
mechanism in the window frame 20, the ledge 8 is housed in a socket (not
shown) in the window frame. The fence 40 limits movement of the base 1 into
the socket, and bears against a vertical surface in the socket to stabilize
the
mechanism, i.e. to reduce or eliminate torque on the screws holding the base 1
in position during operating of the mechanism.
The cover 5 includes a top wall 42, an end wall 43, side walls 44 and a
hole 45 for receiving the hub 29 on the housing 4.
The handle assembly 6 includes a base 47 with a splined socket 48 for
mounting on the top end 35 of the worm gear 3 and a handle 49 pivotally
connected to the base 47. A knob 50 on the outer free end of the handle 49
facillitates manual manipulating of the handle.
When installing the mechanism in the bottom 21 of a window frame 22,
the shoulder 20 on the base 1 and the fence 40 on the housing 4 limit movement
of the mechanism into a stepped opening in the frame. The mechanism is
installed in either side of the frame 22 depending upon whether the window is
right opening (Figs. 6 and 7) or left opening (Figs. 8 and 9). For a right
opening
window, the mechanism is mounted on and in the left side of the window frame
22, and for a left opening window, the mechanism is mounted on and in the
right
side of the window. The outer end of the crank arm 2 is pivotally connected to
the bottom corner of the sash 18. The post 17 is slidably mounted in a
conventional track on the bottom of the window. The mechanism is used with a
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conventional pivot arm 52, which does not form part of the present invention.
The ends of the arm 52 are pivotally connected to the window frame 19 and to
the bottom fo the sash 18.
As mentioned above, with most conventional window operating
mechanisms, it is necessary to provide right and left opening versions, which
are
ideritical except that the crank arm for one is the mirror image of the crank
arm
for the other version. In the case of the present invention, the crank arm 2
is
rotated completely to one end of the row of teeth 30 before connecting the
crank
arm to a window sash 18 in the fully open position. Rotating of the crank arm
2
in the opposite direction will cause the window to move to the closed
position.
When the mechanism is to be used to open the window in the opposite direction
(i.e. left instead of right), the crank arm 2 is rotated completely to the
other end of
the row of teeth 30 before connecting the arm to the bottom corner of a window
sash 18 in the fully open position.
It will be appreciated that the crank arm 2 can be used alone, i.e. without
the siding arm 13, particularly with small windows. When the arm 13 is
required,
it is merely necessary to slide the end 12 of the arm into the notch 10 so
that the
bar 15 enters the recess 16 and use screws to connect the elements together.
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