Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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SYSTEM FOR SHOE LATCHING IN LATERALLY REMOVABLE SASH
FIELD OF THE INVENTION
Support and counterbalancing of heavy sash that are laterally removable from
between opposed jambs of a window.
BACKGROUND
Large and heavy window sash, such as those used in schools, offices, and
institutional buildings, move vertically between opposed pairs of jambs that
are generally
extruded of metal. A sash for such a window can weigh over 100 pounds so that
a
counterbalance system for shoes supporting such a sash must exert a
corresponding
upward lift. Locking the support shoes of the counterbalance system within the
jambs
must be secure and reliable, because of the large spring forces involved.
Also, the sash
support must make a heavy sash easy to raise and lower, and removal and
replacement of a
sash must be convenient and reliable. Since such windows are often used in
schools, the
counterbalance support system must also be tamper resistant to the
manipulations of
curious children. Besides these requirements, an effective window system must
accomplish all the necessary functions in a reliable way with elements that
are inexpensive
to manufacture and maintain.
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This invention improves upon solutions proposed in U.S. Patent No. 6,948,279
and U.S. Patent No. 5,231,795 for supporting and counterbalancing a heavy sash
that is laterally removable from between opposed jambs of a window. The sash
counterbalancing and removal problem is the same one addressed in the `795 and
`279 patents, but the new solution of this invention offers improvements on
the
performance provided by the `795 and `279 patents.
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SUMMARY OF THE INVENTION
As in U.S. Patent No. 6,948,279, the instant system for support of
a sash that is laterally removable from between opposed window jambs uses
sash support arms that are movably arranged for transferring the weight of the
sash to the
shoes and for bridging distances between the sash stiles and the shoes. When
not
supporting the weight of the sash, the support arms move to positions that
allow the sash
to be lifted off of counterbalance support shoes and laterally removed from
between the
window jambs and conversely reinserted between window jambs and lowered onto
the
shoes. This is done while the shoes are locked in positions within the window
jambs.
When the support arms support the weight of the sash, they are in positions
that rest the
sash weight on the counterbalance shoes to support the weight of the sash.
The counterbalance shoes, which are biased upwardly by counterbalance springs,
cooperate with the sash support arms. The shoes receive and support the sash
weight
transferred to the shoes by the sash support arms, and the shoes have hooks
that can be
deployed to lock the shoes reliably in the jambs by engaging projections
formed in the
jambs for this purpose. An improvement taught in the instant application is
the provision
of support arm latching members on the hooks in the form of rear extensions
that latch
over interlock pins extending from the support arms when the hooks are
disengaged from
the jambs. Thus, as taught herein, the same hook elements that serve to hold
the shoes in
position when engaged to the jambs serve to further secure the support arms
for the sash in
position on the shoes when disengaged from the jambs.
DRAWINGS
FIGS. 1 through 5 illustrate a basic embodiment for a system for shoe latching
in laterally removable sash in accordance with the teachings of U.S. Patent
No. 6,948,279, and are included for the basic understanding of the underlying
system and workings of the instant invention provided thereby.
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FIGS. 1 through 3 schematically illustrate the removal and replacement
of a sash supported by the inventive system of U.S. Patent No. 6,948,279 with
the
sash moved laterally for removal or insertion in FIG. 1, lifted above or
lowered onto
counterbalance shoes in FIG. 2, and supported on counterbalance shoes in FIG.
3.
FIGS. 4 and 5 are partially cut-away elevational views showing preferred
embodiments of sash support arms and counterbalance shoes of U.S. Patent
No. 6,948,279, with a shoe locked in a jamb in FIG. 4 and unlocked from a
jamb in FIG. 5.
FIGS. 6A through 10 illustrated a preferred embodiment incorporating an
improved system for shoe latching in laterally removable sash in accordance
with the
teachings of the instant invention.
FIG. 6A provides a first perspective view of a preferred embodiment
incorporating
the teachings of the instant invention.
FIG. 6B provides a first side view of a preferred embodiment incorporating the
teachings of the instant invention.
FIG. 6C provides a second perspective view of a preferred embodiment
incorporating the teachings of the instant invention.
FIG. 6D provides a view from 6D-6D of FIG. 6B of the preferred embodiment
incorporating the teachings of the instant invention.
FIG. 6E provides a view from 6E-6E of FIG. 6B of the preferred embodiment
incorporating the teachings of the instant invention.
FIG. 7 provides a perspective view of the shoe illustrated in FIGS. 6A through
6E.
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FIG. 8 provides a side view of the shoe illustrated in FIGS. 6A through 6E.
FIG. 9 provides a side view of the bracket and support arm illustrated in
FIGS. 6A
through 6E.
5
FIG. 10 provides a perspective view of the bracket and support arm illustrated
in FIGS.
6A through 6E.
DETAILED DESCRIPTION
A sash supported according to this invention is laterally removable from
between a pair of
opposed window jambs in a way that is similar to the sash removal shown in
U.S. Patent
No. 6,948,279. The instant system differs from that shown in U.S. Patent No.
6,948,279
principally in regard to improvements related to its improved shoe locking
hooks 1. Thus, in the
preferred embodiments of the instant application illustrated in FIGS. 6A
through 10, support arm
latching members are provided on the improved hooks 1 in the form of rear
extensions lA. Rear
extensions IA latch over new interlock pins 2A provided in and extending from
support arms 20
when the improved hooks 1 are disengaged from their adjacent jambs. Therefore,
the same
improved hooks 1 that serve to hold improved shoes 3 in position when engaged
to the jambs
serve to further secure the support arms 20 for the sash in position on
improved shoes 3 when
disengaged from the jambs. In other respects, the preferred embodiments of the
instant
application and their use can be best understood by review of the more basic
embodiment
illustrated in FIGS. 1 through 5 and the teachings of U.S. Patent No.
6,948,279.
The operation of a basic embodiment of the inventive system, as described in
more detail in U.S. Patent No. 6,948,279, is shown schematically in FIGS. 1-3.
Sash 10,
as shown in FIG. 1, is lifted off of shoes 30 that are locked in place within
jambs 11,
which are illustrated by broken lines extending along the light opening
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between jambs 11. For heavy sash that benefit from the inventive support
system, jambs
11 are generally extruded of metal to allow lateral room for maneuvering sash
10 in
between and out from between jambs 11. Jambs 11 are essentially the same as
jambs used
with the sash support system of the '795 patent, and such jambs are available
in different
dimensions to accommodate different sizes of sash 10 and corresponding
counterbalance
systems. Sash 10, in the position shown in FIG. 1, is also moved laterally
within jambs 11
to free one stile edge of sash 10 from jambs 11 for maneuvering sash 10 out
from between
jambs 11 or back into a position between jambs 11.
In the position shown in FIG. 2, sash 10 is centered between jambs 11 but
elevated
above locked shoes 30, as it is lifted off from or lowered onto shoes 30. In
the position
shown in FIG. 3, sash 10 is again centered between jambs 11, but is lowered
onto shoes
30, which are no longer locked within jambs 11. In the supported position
shown in FIG.
3, sash 10 rests on and is supported by shoes 30 by means of sash support arms
20 that are
moved to an outward position. Arms 20 are in inward positions when sash 10 is
lifted off
of shoes 30, as shown in FIGS. I and 2.
Besides the preferred pivoting of sash support arms 20 on the stiles of sash
10, as
illustrated in FIGS. 1-3, it is also possible to arrange sash support arms
that are pivotally
mounted on shoes 30. With such an arrangement, shoe mounted sash support arms
would pivot inward to engage sash stiles and support the weight of a sash
engaged by
the arms, which are preferably braced against pivoting when in a support
position.
Pivoting the support arms on the shoes can thus achieve a similar result to
the preferred
pivoting of the support arms on the sash stiles. Either way, the support arms
transfer the
sash weight to the shoes and move from sash support positions when the sash is
uplifted
from the shoes, to allow lateral movement and withdrawal of the sash from the
jambs.
As best shown in FIGS. 4 and 5, support arms 20 are pivotally mounted on
brackets 21 of mounts 22 that are secured to the stiles of sash 10, which have
a recessed
edge groove that receives mount brackets 22. Pivot pins 23 support arms 20 on
brackets
21 to pivot between outwardly extending positions shown in FIGS. 4 and 5, and
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downwardly dependent positions shown in FIGS. I and 2. Each of these positions
is
limited and braced by mount 22. In the outwardly extending position, an end 24
of arm 20
abuts against mount 22 to brace arm 20 against pivoting upward. In the
downwardly
dependent position, an abutment 25 on support arm 20 engages a lance 26 on
mount 22 to
prevent pivoting of support arm 20 downward or inward beyond the position
shown in
FIG. 10.
A lower region 36 of shoe 30 has a sash support platform 37 that is engaged by
the
ends 27 of sash support arms 20 to uphold the weight of sash 10. Platforms 37
extend
toward sash 10 far enough to engage sash support arms 20 in their inward
positions. The
extension of platforms 37 towards sash 10 also leaves free room above
platforms 37 for
sash 10 to be moved laterally while it is raised above platforms 37 and
maneuvered out of
or into the space between opposed jambs 11. As a sash 10 is lowered into a
supported
position on shoes 30, the ends 27 of support arms 20 first engage inner end
regions 38 of
support platforms 37; and then as sash 10 is further lowered, arm ends 27
slide outward
along platforms 37 to the support position illustrated in FIGS. 4 and 5. The
reverse occurs
as sash 10 is lifted up off of shoes 30.
The small step 39 in platform 37 is preferred for resisting lateral movement
of
sash 10 while resting on shoes 30 and as a positive indication that arm ends
27 of a sash
being lowered have reached appropriately supported positions on platforms 37.
The
regions where arm ends 27 support sash 10 on platforms 37 are preferably
directly
below slots 32 where counterbalance elements exert an upward force on upper
regions
31 of shoes 30. This minimizes any moment arms tending to turn shoes 30 around
horizontal axes.
Below platform 37 is preferably arranged a pivot pin 43 for a shoe-locking
hook.
In FIGS. 1 through 5, illustrating the exemplary teachings of a basic
embodiment of the
invention (as more thoroughly taught and described in copending application
Serial
Number 08/839,161), this shoe-locking hook is hook 45. In the preferred
embodiment of
the instant invention, as illustrated in FIGS. 6A through 10, this is improved
hook 1. In
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either, a hook end 46 interlocks with a projection or lance 47 formed in jamb
wall 12, as
illustrated in FIG. 4.
In the basic embodiments illustrated in FIGS. 1 through 5, the underside of
the
inward region 38 of support platform 37 has a groove 41 that receives and
retains a
resilient latch spring 40. An anchored end 51 of spring 40 can be pressed into
slot 41 of
the basic embodiment to retain spring 40 frictionally in place. In the basic
embodiments, a
downwardly extending projection 52 engages spring 40 to prevent movement
beyond a
resilient latching position, as illustrated. Hook 45 of the basic embodiment
has a latching
nose 48 that latches into an opening 42 in spring 40, as illustrated in FIG.
5. Latching
nose 48 and spring 40 are preferably configured so that shoe-locking hook 45
can be
manually pushed into the latched position shown in FIG. 5. Unlatching shoe
lock 45 for
deployment preferably requires pressing a screwdriver blade in between hook
end 46 and
the free end 49 of spring 40. This makes the accidental deployment of shoe
locks 45 of the
basic embodiment unlikely.
In the preferred embodiment illustrated in FIGS. 6A through 10, support arm
latching members are provided on improved hooks I in the form of rear
extensions lA.
Rear extensions lA can be latched over interlock pins 2A provided in and
extending
from the sides of support arms 20 when the improved hooks 1 are disengaged
from
their adjacentjambs. (This serves to hold the support arms 20 in place on
improved
shoes 30A, supplementing the weight of the sash in accomplishing this
purpose).
Thus, the same improved hooks 1 that serve to hold improved shoes 30A in
position
when engaged to the jambs serve to further secure the support arms 20 for the
sash in
position on improved shoes 30A when disengaged and swung away from the jambs
and over interlock pins 2A.
Fasteners are also provided to hold rear extensions lA in latched position
over
interlock members (pins 2A). In the preferred embodiments illustrated, these
fasteners
include notches I B near the ends of extensions 1 A that snap into spring
loaded snaps
30B provided in improved shoes 30A. The fastener formed by the combination of
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notches 1B and snaps 30B is intended to be, and is, very strong so as to
prevent casual
release of improved hooks 1(by, for example, school children). A slot 1C is
provided in
improved hooks 1 for the insertion of a screw driver head or other tool to
force the
release of notches 1B from snaps 30B so as to allow improved hooks 1 to attach
to
adjacent jambs. However, numerous changes can be made in the structure of the
foregoing elements (as with other elements herein described) without exceeding
the ambit
of the inventive concept. Accordingly, it is to be understood that the
embodiments of the
invention herein described are merely illustrative of the application of the
principles of the
invention. Reference herein to details of the illustrated embodiments is not
intended to
limit the scope of the claims, which themselves recite those features regarded
as essential
to the invention.
