Note: Descriptions are shown in the official language in which they were submitted.
`` 13~9~
Background of the Invention
This invention relates generally to apparatus for
use with windows and specifically for use with windows
such as a casement window having a sash which is
adapted to be swung about an upright axis between
closed and open positions.
Modern casement windows usually are associated
with a reversible rotary actuator which may be used to
open and close the window sash. The actuator may be in
the form of a hand crank adapted to be turned in one
direction to open the sash and in the opposite
direction to close the sash. Alternatively, the
actuator may be a reversible electric motor which is
associated with the sash in the manner disclosed in
Lense Vnited States Patent 4,553,656.
A casement window usually is equipped with one or
more latches for locking the sash in its closed
position. While the latch may be power-operated as
disclosed in Lense United States Patent 4,703,960, the
latch more conventionally is operated manually. If the
latch is locked, it must be unlocked before the sash
can be opened and then must be re-locked to secure the
sash a~ter the latter has been closed. In prior
windows with manually operable latches, two separate
operations are necessary in order to unlock and open
the sash and then two more separate operations are
required to close and lock the sash. In some cases,
the sash may be fully closed but inadvertently left in
an unlocked condition.
i3.~9~3~
Vetter et al United States Patent 4,497,135
d,iscloses mechanism for automatically unlocking and
opening a sash and for automatically closing and
locking the sash. That mechanism, however, is
relatively complex and requires a motor, planetary
gearing driven by the motor and a trigger for sensing
the position of the sash.
Summary of the Invention
The general aim of the present invention is to
provide new and improved window apparatus in which the
sash actuator is uniquely linked to the sash and to the
sash latch by relatively simple mechanism capable of
effecting automatic unlocking of the latch when the
sash actuator is operated to open the sash and
automatic locking of the sash when the actuator is
operated to close the sash.
Another object of the invention is to use the sash
actuator to effect automatic unlocking of the sash just
prior to opening of the sash and t~ effect automatic
locking of the sash at about the same time the sash
reaches its fully closed position without need of
relying on a sensor or the like for detecting the
position of the sash.
A more detailed object is to achieve the foregoing
by providing apparatus in which a single sash actuator
operates extremely simple latch and sash linkages in a
predetermined timed relationship resulting in unlocking
of the sash just prior to opening of the sash and
resulting in locking of the sash during or just after
full closure of the sash.
Still another object is to provide a sash linkage
which positively holds the sash against buffeting when
the sash is in an open position.
1 3 ~
The invention also resides in the novel construction
of the latch to facilitate the opening of a stuck sash
and to help draw the sash to a fully closed position.
In brief, the invention involves apparatus for mov-
ing a swingable window sash toward and away from a closed
position relative to a fixed window frame and for releas-
ably locking the sash in its closed position, said
apparatus comprising a strike mountable on said sash, a
latch mountable on said frame to move between locked and
unlocked positions, said latch being operable when in
said locked position to engage said strike and hold said
sash in said closed position and being operable when in
said unlocked position to release said strike and free
said sash for movement away from said closed position, a
reversible rotary actuator mounted on said frame,
mechanism responsive to rotation of said actuator in a
first direction to first move said latch from said locked
position to said unlocked position and to then move said
sash away from said closed position, said mechanism being
responsive to rotation of said actuator in a second
direction to first move said sash toward said closed
position and then to move said latch toward said locked
position at about the same time said sash reaches said
closed position, said mechanism comprising a screw
coupled to said actuator for rotation by the latter,
first and second nuts movable back and forth along said
screw, a first linkage connected between said sash and
said first nut and operable to move said sash away from
said closed position when said first nut is moved in one
direction along said screw and to move said sash toward
said closed position when said first nut is moved in the
opposite direction along said screw, a second linkage
connected between said latch and said second nut, said
second linkage being operable to move said latch toward
said unlocked position when said second nut is moved in
said one direction along said screw and to move said
latch toward said locked position when said second nut is
~'
`` 1 3 ~
moved in said opposite direction along said screw, and
means operable when said sash is in said closed position
and said latch is in said locked position to delay move-
ment of said first nut in said one direction along said
screw until said screw has been rotated sufficiently far
to advance said second nut along said screw a predeter-
mined distance in said one direction, and said means also
being operable when said sash is in said closed position
and said latch is in said unlocked position to prevent
movement of said first nut along said screw in said
opposite direction during rotation of the screw while
permitting said second nut to move along said screw in
said opposite direction.
The invention also resides in apparatus for moving a
swingable window sash between open and closed positions
relative to a fixed window frame and for releasably lock-
ing the sash in its closed position, said apparatus com-
prising a strike mountable on said sash, a latch mount-
able on said frame to move between locked and unlocked
positions, said latch being operable when in said locked
position to engage said strike and hold said sash in said
closed position and being operable when in said unlocked
position to release said strike and free said sash for
movement away from said closed position, a reversible
rotary actuator mountable on said frame, first and second
linkages connected to said sash and said latch, respec-
tively, said first linkage being responsive to said actu-
ator to move said sash away from said closed position
when said actuator is rotated in one direction and to
move said sash toward said closed position when said
actuator is rotated in the opposite direction, and said
second linkage being responsive to said actuator to move
said latch toward said unlocked position just prior to
initial movement of said sash away from its fully closed
position and to move said latch toward its locked posi-
tion at about the same time said sash returns to its
fully closed position, said second linkage including an
3.~
~3~3~
element movable back and forth along the bottom of said
frame, second linkage further including an elongated
member connected to said element, said elongated member
being laterally flexible and extending along the bottom
of said frame and upwardly along one side of said frame,
said elongated member being longitudinally stiff and
being capable when pushed by said element to move said
latch between said locked and unlocked positions.
These and other objects and advantages of the inven-
tion will become more apparent from the following
detailed description when taken in conjunction with the
accompanying drawings.
Brief Descri~tion of the Drawinqs
FIGURE 1 is a perspective view of a window e~ipped
with one embodiment of new and improved apparatus incor-
porating the unique features of the present invention and
shows the sash in a partially open position.
FIG. 2 i8 an enlarged fragmentary cross-section
taken substantially along the line 2-2 of FIG. 1 but
shows the sash in a closed and locked position.
FIG. 3 is an enlarged cross-section taken substan-
tially along the line 3-3 of FIG. 1 and also shows the
sash in a closed and locked position.
FIGS. 4, 5 and 6 are enlarged fragmentary cross-
sections taken substantially along the lines 4-4, 5-5 and
6-6, respectively, of FIG. 3.
FIG. 7 is a view similar to FIG. 3 but shows the
sash in a partially open position.
FIG. 8 also is a view similar to FIG. 3 but shows
the sash in a fully open position.
FIG. 9 is an enlarged fragmentary cross-section
taken substantially along the line 9-9 of FIG. 3.
FIGS. 10 and 11 are fragmentary cross-sections taken
substantially along the lines 10-10 and 11-11, respec-
tively, of FIG. 9.
3B
~3~;3~
FIGS. 12 to 15 are elevational views of one of the
latches illustrated in FIG. 9 and show the latch in
successively moved positions.
FIG. 16 is a perspective view of another
embodiment of apparatus incorporating the features of
the invention, the view showing the sash closed but
unlocked.
FIG. 17 is a cross-section taken substantially
along the line 17-17 of FIG. 16, the sash being shown
closed and locked.
FIGS. 18, 19 and 20 are enlarged f ragmentary
cross-sections taken substantially along the lines
18-18, 19-19 and 20-20, respectively, of FIG. 17.
FIG. 21 is an enlarged fragmentary cross-section
taken along the line 21-21 of FIG. 17 and shows the
parts of the apparatus as positioned when the sash is
closed and locked.
FIG. 22 is a view similar to FIG. 21 but shows the
parts as positioned when the sash is unlocked and is
just starting to open.
FIG. 23 is a view similar to FIG. 17 but shows the
sash fully open.
Detailed DescriPtion of the Preferred Embodiment
For purposes of illustration, the invention is
shown in the drawings as being embodied in apparatus
for causing a casement window sash 20 to swing between
closed and open positions in a window frame 21 and for
releasably locking the sash in its closed position.
The sash itself is of conventional rectangular
construction and includes a glass pane 22 which is
supported by horizontal top and bottom members 23 and
24 and by left and right upright side members 25 and
26.
~ 3 1 ~
The frame 21 also is rectangular and is defined by
a top header 27, a bottom sill 28 and by left and right
side jambs 29 and 30 (FIG. 3). Generally channel-
shaped moulding strips 31 ~FIG. 6) and 32 (FIG. 3)
extend alongside the sill 28 and the righ~ side jamb
30, respectively, a moulding strip 33 (FIG. 3) extends
al~ngside the left side jamb 29 and an additional
moulding strip (not visible) is located alongside the
header 27. A screen 34 (FIG. 2) is removably
positioned in the opening defined by the frame 21.
To support the sash 20 for movement between its
closed and open positions, a horizontal track 35 (FIG.
7) is attached to the sill 28 adjacent the left side
jamb 29 and is formed with an elongated and laterally
extending slot 36. The slot receives a pivot pin 37
which extends downwardly from the bottom member 24 of
the sash. Similar structure (not fully visible) is
located at the upper left portion of the sash. During
opening of the sash, the pin 37 moves from left-to-
right in the slot 36 and, at the same time, the sash
swings counterclockwise (FIG. 7) about the axis of the
pin. The sash swings clockwise about the axis of the
pin 37 as the sash is closed and as the pin moves from
right-to-left in the slot 36. Movement of the sash is
controlled in part by a swivel arm 38 having an outer
end pivotally connected to the bottom member 24 of the
sash and having an inner end pivotally connected to the
sill 28. A similar swivel arm 39 (FIG. 1) is located
at the top of the sash.
Opening and closing of the sash 20 is effected by
a reversible rotary actuator 40 which, in this
particular instance, includes a conventional hand crank
41. The crank is connected rigidly to the inner end
portion of a spindle 42 (FIG. 2) which is rotatably
journaled in an actuator cover 43 fastened to the sill
~3~99`~
28 by screws 44 (FIG. 4). A bevel gear 45 (FIG. 2~ on
the outer end of the spindle meshes with a bevel gear
46 on a shaft 47 which is rotatably supported within
the cover and which carries a worm 48. T~e sash 20 is
opened and closed when the crank 41 is turned clockwise
(FIG. 1) and counterclockwise, respectively.
When the sash 20 is in its closed position, it is
adapted to be locked releasably and, in this instance,
the locking is effected by upper and lower latches 49
and 50 (FIGS. 1 and 9) although, in many cases, a
single latch could be used to lock the sash. Each
latch includes a base plate 51 (FIG. 9) fastened to the
right side jamb 30 and located between the jamb and the
channel-shaped moulding 32. Rotatably supported on a
horizontal pin 52 on each base plate is a latching bolt
53 formed with a U-shaped notch or throat 54. The
latch bolts of the upper and lower latches 49 and 50
are adaptd to coact with upper and lower strikes 55 and
56 (FIGS. 1 and ~), respectively, supported on the
inner side of the right frame member 26 of the sash
20. Each strike includes a generally triangular
mounting plate 57 (FIGS. 9 and 11) attached to the
frame member 26 and supporting a horizontal pin 58
which projects toward the right side jamb 30. When the
latch bolts 53 are in locked positions shown in FIG. 9,
the strike pins 58 are captivated within the throats 54
of the latch bolts so as to prevent opening of the sash
20. When each latch bolt is rotated counterclockwise
to an unlocked position shown in FIG. 15, the throat 54
releases the strike pin and frees the sash to open. A
torsion spring 59 encircles the mounting pin 52 of each
latch bolt and urges the latch bolt toward its unlocked
position.
In accordance with the present invention,
operation of the rotary actuator 40 in one direction
3 ~3
automatically effects movement of the latching bolts 53
to their unlocked positions and then effects opening of
the sash 20. When the rotary actuator is operated in
the opposite direction, the sash is closed and, at
about the same time the sash reaches its fully closed
position, the actuator effects automatic movement of
the latch bolts to their locked positions. In this
way, only one operation is required to unlock and open
the sash and only one operation is required to close
and lock the sash.
More specifically, the rotary actuator 40 includes
an actuating or driver arm 60 which is supported to
turn back and forth about a vertical pivot defined by a
screw 61 in the cover 43. The inner end portion of the
driver arm is formed with gear teeth and defines a gear
segment 62 which meshes with the worm 48 of the
actuator 40. When the hand crank 41 of the actuator is
turned back and forth, it acts through the bevel gears
45 and 46, the worm 48 and the gear segment 62 to turn
the driver arm 60 back and forth about the pivot 61.
Pursuant to the invention, back and forth turning
of the driver arm 60 effects locking and unlocking of
the latch bolts S3. For this purpose, a pair of
identical and vertically spaced links 63 (FIGS. 3 and
5) are pivotally connected to the free end portion of
the driver arm at 64. The opposite end portions of the
links 63 pivotally receive a vertical drive pin 65
connected rigidly to and projecting upwardly from a
block-like slide 66 which forms part of an actuating
linkage to the latches 49 and 50. The slide is located
within a metal guide or track 67 of inverted U-shaped
cross-section extending along the sill 28 and fastened
to the sill by screws 68. A plastic guide channel 69
(FIG. 2) is located in the track 67 and supports the
slide 66 for back and forth movement in the track.
~3~3~
During such movement, the drive pin 65 travels in a
straight slot 70 ~FIG. 3) formed through the top of the
track 67 and extending lengthwise of the sill 28.
Connected to the lower side of the slide 66 by a
pair of rivets 71 (FIG. 5) is one end portion of a
longitudinally stiff but laterally flexible elongated
member which herein is a length of tape 72 made of
metal or plastic. The tape 72 extends between the
guide channel 69 along the sill 28 toward the right
side jamb 30 and then curves upwardly and extends along
the jamb, the guide channel also curving upwardly and
extending along the jamb. The upper end portion of the
drive tape 72 is connected by fasteners 73 to a block
74 which is supported for up and down sliding in the
guide channel 69. A mounting bracket 75 ~FIG. 9) is
connected to the block by the fasteners 73 and is
rigidly connected at 76 to the lower end of a rigid and
vertically extending bar 77 which is guided for up and
down movement by tabs 78 on the mounting plates 51 of
the latches 49 and 50.
When the sash 20 is fully closed, the bar 77 is
positioned as shown in FIG. 9 and, when so positioned,
vertically spaced pins 79 on the bar bear against
vertically extending edges 80 of the latch bolts 53 and
positively hold the latch bolts against turning
counterclockwise from their locked positions. When the
bar is shifted upwardly from the position shown in FIG.
9, the pins 79 move upwardly off of the vertical edges
80 and effect unlocking of the latch bolts in a manner
which will subsequently be described in detail.
~ownward return of the bar to the position shown in
FIG. 9 causes the pins to turn the latch bolts
clockwise to their locked positions in a manner which
also will be described in more detail below.
3 ~
In carrying out the invention, the same actuator
arm 60 for unlocking and locking the latches 49 and 50
also acts through a linkage to effect opening and
closing of the sash 20. To this end, the linkage
includes an arm 81 (FIG. 7) pivotally mounted to turn
about a vertical screw 82 in the cover 43 and formed
with a slot 81 which receives the driver pin 65. Part
of the arm 83 overlies the track 67 and its free end is
pivotally connected at 84 to one end of a link 85. The
other end of the link is pivotally connected at 86 to a
bracket 87 secured to the bottom member 24 of the sash
20 adjacent the left side member 25 thereof. When the
sash arm 81 is turned clockwise about the pivot 82, it
acts through the link 85 to cause the sash 20 to move
from a fully closed position shown in FIG. 3, to an
intermediate position shown in FIG. 7 and then to a
fully open position shown in FIG. 8. Counterclockwise
turning of the arm 81 moves the sash reversely and
returns the sash toward the fully closed position shown
in FIG. 3.
Importantly, the slot 83 in the sash arm 81 is
shaped such that, when the sash 20 is fully closed,
initial clockwise turning of the driver arm 60 causes
the pin 65 to shift the slide 66 to the right to effect
unlocking of the latches 49 and 50 but does not produce
movement of the sash arm 81 to open the sash 20. After
the latches have been at least partially unlocked,
continued clockwise turning of the driver arm 60 causes
the pin 65 in the slot 83 to effect clockwise turning
of the sash arm 81 and opening of the sash 20.
The foregoing is achieved by shapinq the slot 83
in the sash arm 81 such that it includes an elongated
straight portion 88 which overlies and extends parallel
to the slot 70 in the track 67 when the sash 20 is
fully closed and locked as shown in FIG. 3. At the
~3~3~
right end of the straight portion 88, the slot 83 is
formed with a curved portion 89 which extends generally
inwardly. The curved portion 89 of the slot 83 is
shaped and located so as to avoid binding interference
with the pin 65 as the arm 81 turns and as the pin
moves in the slot 70.
When the sash 20 is fully closed and locked, the
arms 60 and 81 are positioned as shown in FIG. 3 and,
in this position, the driver pin 65 is located in the
straight portion 88 of the slot 83. When the hand
crank 41 is rotated to turn the driver arm 60
clockwise, the links 63 pull the driver pin 65 to the
right and, because the driver pin is constrained by the
slot 70 in the track 67, the pin travels in a straiqht
line and produces no turning force against the edges of
the straight portion 88 of the slot 83 in the sash arm
81. The pin 65 does, however, cause the slide 66 to
shift to the right. The slide acts through the
longitudinally stiff tape 72, the block 74 and the
bracket 75 to shift the bar 77 upwardly and cause the
pins 79 to move upwardly to positions unlocking the
latch bolts 53 (see FIG. 14).
With continued clockwise turning of the driver arm
60, the rightwardly moving drive pin 65 encounters the
outside edge of the curved portion 89 of the slot 83 in
the sash arm 81. As a result, the pin 65 starts
turning the sash arm 81 clockwise and starts opening
the sash 20. As the sash opens, the curved portion 89
of the slot 83 turns into embracing relation with the
drive pin 65 and continues to turn into embracing
relation with the pin until the sash has opened through
an angle of about 45 degrees as shown in FIG. 7. Vpon
still further clockwise turning of the driver arm 60,
the curved portion 89 of the slot 83 starts turning out
of embracing relation with the drive pin 65 (see FIG.
~31~3~
8~ but the pin continues to apply a turning moment to
the edge of the slot and continues to open the sash
until the sash has been opened through about 90
degrees.
When the driver arm 60 subsequently is turned
counterclockwise, the driver pin 65 bears against the
opposite edge of the curved portion 89 of the slot 83
and forces the sash arm 81 to turn counterclockwise to
close the sash 20. During counterclockwise turning of
the driver arm, the curved portion 89 of the slot 83
first moves into and then out of embracing relation
with the drive pin 65 as the drive pin continues to
bear against the edge of the slot. When the pin 65
starts moving to the left in the straight portion 88 of
the slot 83, the sash is fully closed and the remainder
of the leftward movement of the pin acts through the
slide 66 and the tape 72 to pull the bar 77 downwardly
and cause the pins 79 to hold the latch bolts 53 in
their locked positions shown in FIG. 9.
The specific manner in which the latch bolts 53
are unlocked is illustrated in FIG. 9 and in FIGS. 12
to 15. In FIG. 9, the bar 77 is shown in the
downwardmost position which the bar occupies when the
sash 20 is fully closed and no further counterclockwise
turning of the crank 41 is possible. As stated above,
the pins 79 engage the vertical edges 80 of the latch
bolts 53 when the bar is positioned as shown in FIG. 9
and positively prevent counterclockwise turning of the
latch bolts. This defeats any attempt to open the sash
20 from the outside by pulling on the sash.
When the drive pin 65 first starts moving to the
right, each pin 59 moves upwardly from the position
shown in FIG. 9 to the position shown in FIG. 12 and
begins to enter a notch 90 in the inner edge of the
associated latch bolt 53. When the pin 59 is
3 ~
positioned as shown in FIG. 12, the sash 20 has not yet
started to open.
With continued upward movement, each pin 59 bears
against the upper edge of the respective notch 90 and
starts turning the latch bolt 53 counterclockwise
toward its unlocked position. Just shortly thereafter,
the sash 20 starts to open as shown in FIG. 13. As the
pin 59 continues upwardly and as the latch bolt 53
continues to turn, a curved edge 91 of the throat 54 in
the bolt cams against the strike pin 58 as shown in
FIG. 14 and positively forces the pin outwardly to help
open a sash which might be stuck by paint or ice. As
the pin 59 moves upwardly out of the notch 90, the
torsion spring 59 forces the latch bolt to its fully
unlocked position shown in FIG. 15 to free the strike
pin 58 and permit full opening of the sash 20.
When the bar 77 is shifted downwardly, each pin 59
enters the notch 90 in its respective latch bolt 53 and
turns the latch bolt clockwise. As an incident
thereto, the outer edge 92 of the throat 54 engages the
strike pin S8 and helps draw the sash 20 inwardly to a
tightly sealed position. The pin 59 then leaves the
notch 90 and moves into abutting engagement with the
vertical surface 80 of the locking bolt 53. While in
this specific instance the latching bolt draws the sash
inwardly and turns to its fully locked position at the
same time the sash reaches its fully closed position,
it will be appreciated that the latch bolt could reach
its fully locked position shortly after the sash is
fully closed.
From the foregoing, it will be apparent that the
present invention brings to the art new and improved
apparatus which requires only a single operation to
unlock and open the sash 20 and requires only a single
operation to close and lock the sash. The task of
1 3 i ~
opening and closing the sash thus is simplified and, in
addition, there is less chance of inadvertently leaving
the sash unlocked. If desired, indicia of different
colors (e.g., green and red) may be placed on each
latch bolt 53 to indicate when the bolt is locked and
unlocked.
Those familiar with the art will recognize that a
power-operated actuator such as disclosed in Lense
United States Patent 4,553,656 may be used in place of
the hand crank 41. Also, the principles of the
invention may be used in conjunction with other types
of windows such as awning windows.
Another embodiment of apparatus incorporating the
features of the invention is shown in FIGS. 16 to 23 in
which parts corresponding to those of the first
embodiment are indicated by the same but primed
reference numerals. The apparatus of the second
embodiment is particularly characterized by its ability
to hold the sash 20' very rigidly when the sash is in
its open position and thereby prevent the sash from
being buffeted by wind.
For all practical purposes, the latches 49' and
50' ~FIG. 16) of the second embodiment are identical to
those of the first embodiment. Each latch 49', 50'
includes a rotatable latch bolt 53' adapted to be
turned clockwise from an unlocked position shown in
FIG. 16 to a locked position. Such turning is effected
by means of pins 79' attached to a vertical bar 77' and
operable to rotate the latch bolts in a clockwise
direction when the bar is shifted downwardly. When the
bar is shifted upwardly, torsion springs (not shown)
turn the bolts counterclockwise from their locked
positions to their unlocked positions shown in FIG.
16. Upward and downward shifting of the bar is
effected by pushing and pulling a metal tape 72' whose
13
131~
upper end is connected to the lower end of the bar by a
bracket 75'.
As before, opening and closing of the sash 20' and
unlocking and locking of the latch bolts 53' are
effected in response to turning of a reversible rotary
actuator or crank 41'. The crank is connected rigidly
to the inner end portion of a spindle 42' (FIG. 18)
which is rotatably journaled in an actuator cover 43'
fastened to the sill 28'. A bevel gear 45' on the
outer end of the spindle 42' meshes with a right-angle
bevel gear 100.
In carrying out the invention, the bevel gear 100
is attached to one end of a lead screw 101 which is
formed with a helical thread 102 of substantial
width. The right end portion of the lead screw is
journaled for rotation by the actuator cover 43'.
Telescoped over the lead screw are two nuts 104 and 105
and an unthreaded sleeve 106. The nuts 104 and 105 are
formed with threads 107 and 108, respectively, (FIG.
22) adapted to mate with the thread 102 of the screw
101. The nut 105 is located between the nut 104 and
the sleeve lOh.
Unlocking of the latch bolts 53' is effected
during initial movement of the nut 105 to the right
along the screw 101 while locking of the latch bolts is
effected during final movement of the nut lOS to the
left along the screw. For this purpose, the nut 105
includes an outwardly projecting lower flange 109 (FIG.
20) which is connected to the free end of the tape 72'
by a ver~ical rivet 110. As the nut 105 initially
travels to the right, it pushes on the tape 72' to
cause the bar 77' to shift upwardly and permit
unlocking of the latch bolts 53' under the influence of
the torsion springs. As an incident to final travel of
the nut lOS to the left, the nut 105 pulls the tape 72'
14
13~3~
and the bar 77' sufficiently far to cause the pins 79'
to turn the latch bolts 53' to their locked
positions. During movement of the nut 105, the rivet
110 travels in an elongated slot 111 (FIG. 23) formed
in a fixed casing 112 which is supported on the sill
28' and which extends partially around the screw 101,
the nuts 104 and 105 and the sleeve 106. A shroud 113
(FIGS. 19 and 20) encloses the inner and upper sides of
the casing 112 and defines a molding along the sill
28'.
Importantly, the nut 104 and the sleeve 106 are
connected to one another and, when moved to the right
or the left, are operable to open or close the sash
20'. In order to connect the nut 104 and the sleeve
106, a generally U-shaped yoke 115 (FIG. 23) has one
leg rigidly connected to the nut 104 and a second leg
connected rigidly to the sleeve 106. The nut 105 is
disposed within the space between the two legs of the
yoke. An elongated arm 116 (FIG. 17) extends between
and is connected rigidly to the two legs of the yoke
115 and projects beyond the right end of the yoke. One
end portion of a sash link 117 is connected pivotally
to the right end portion of the arm 116 at 118. The
other end portion of the sash link is pivotally
connected at 119 to a bracket 87' secured to the bottom
of the sash 20'. When the yoke 115 is advanced to the
right or the left, it acts through the arm 116 and the
link 117 to open or close the sash 20'.
FIGS. 17 and 21 show the position of the nuts 104
and 105 and the sleeve 106 when the sash 20' is fully
closed and locked. When the parts are so positioned,
the nut 104 is at the extreme left end of the screw 101
while the nut 105 is located immediately adjacent the
nut 104 and is spaced axially from the sleeve 106. As
shown in FIG. 21, the extreme left end portion 120 of
13~3~
the screw 101 is unthreaded and is received in the nut
104 when the sash 20' is closed and locked. The nut
105 receives the threaded portion 102 of the screw 101
but such portion does not extend into tbe nut 104 when
the parts are located in the position shown in FIG.
21. A bracket 125 at the left end of the screw
prevents the nut 104 from sliding to the left off of
the unthreaded portion 120.
As before, unlocking and opening of the sash 20'
are effected by turning the crank 41' clockwise, the
crank acting through the gears 45' and 100 to rotate
the screw 101 clockwise (FIG. 18). When the sash is
closed and locked, initial clockwise rotation of the
screw 101 causes the nut 105 to move from left to right
along the screw and to travel from the position shown
in FIG. 21 to the position shown in FIG. 22. During
such travel, the nut 105 acts through the rivet 110 to
push on the tape 72' and unlock the latch bolts 53'.
The nut 104, however, remains stationary during initial
clockwise rotation of the screw 101 since the
unthreaded portion 120 of the screw is received in the
nut 104 and is not capable of advancing that nut.
When the nut 105 reaches the position shown in
FIG. 22, the latch bolts 53' are fully unlocked. Upon
continued clockwise rotation of the screw 101, the nut
lOS engages the sleeve 106 and forces the sleeve to
move to the right along the screw. As an incident
thereto, the sleeve shifts the yoke 115 to the right
and causes the yoke to pull the nut 104 onto the
threaded portion 102 of the screw. As the screw
continues to rotate, the nuts 104 and 105 force the
yoke 115 to the right and act through the yoke, the
sash arm 116 and the sash link 117 to swing the sash
20' to an open position as shown in FIG. 23.
16
1 3 `1 ~ ~ `3 ~;
When the crank 41' is turned counterclockwise, the
screw 101 also is rotated counterclockwise and drives
the nuts 104 and 105 to the left. As a result, the nut
104 acts to close the sash 20' while the nut 105 acts
through the tape 72' to pull the bar 77' downwardly.
~hen the sash approaches its fully closed position, the
nut 104 runs off of the threaded portion 102 of the
screw 101 and returns to the untbreaded portion 120.
Thus, further counterclockwise rotation of the screw
produces no further closing of the sash by way of the
nut 104. Such rotation does, however, continue to
advance the nut 105 to the left to enable that nut to
pull the bar 77' downwardly sufficiently far to cause
the pins 79' to lock the latch bolts 53'. As an
incident thereto, the bolts exert a draw-in force on
the sash 20' so as to seal the sash in its closed
position.
8y virtue of the coaction between the screw 101
and the nut 104, the sash 20' is held rigidly in all
open positions of the sash. Although the screw and the
nut form a high efficiency transmission and enable the
sash to be opened and closed easily when the crank 41'
is turned, it is virtually impossible for the nut to
turn the screw when an axial force is imposed on the
nut. As a result, the sash is held very rigidly and
does not buffet under the force of high winds.
It should also be noted that the apparatus of the
second embodiment requires significantly fewer
components beneath the cover 43' than is the case with
the apparatus of the first embodiment. As a result,
the cover 43' is trimmer and more compact than the
cover 43.
