Window grill latch

A latch for a window grill utilizes an upper latch member and a lower latch member spring biased together and each having side panels adapted to engage a wedge or cam member for moving the upper and lower latch members toward and away from each other. The upper and lower latch members, as well as the wedge and cam members, are adapted to slidably engage the walls of a generally rectangular housing, which housing acts as a guide to the moving parts.

BACKGROUND OF THE PRIOR ART 
This invention relates generally to latching devices and in particularly to 
latching and quick release devices for window grills. 
Latching and quick release devices for windows in general, are numerous and 
varied. 
For window grills, where the operating handle is located within the 
building and the grill latch is located outside the building, cable 
operated window latch releases are generally used because they can be 
conveniently adapted to pass through the building wall without the need 
for precision location. 
In one prior art device, a telescoping tube spans the joint between two 
abutting tubes or bars of the grill frame. A cable is used to pull the 
telescoping tube away from the joint releasing the two abutting tubes or 
bars thus opening the grill frame. 
In another quick release device, a push rod is used to release a plug-like 
latch mechanism to free the end of a grill support bar and allow the grill 
to swing open. 
A more complex release device utilizes a capsule containing a compressed 
gas. Operation of the cable actuated device punctures the seal on the 
capsule releasing the pressurized gas, which gas pressure is used to 
overcome the retaining force of the latch and release the grill. 
Another quick release latch utilizes a frusto-conical member disposed 
between two roller bars to cause a pair of latching members to separate 
and release the grill bar. 
All of the prior art devices were somewhat complicated and expensive to 
manufacture. 
SUMMARY OF THE INVENTION 
The grill latch of the present invention utilizes an upper latch member and 
a lower latch member which are moved toward and away from each other to 
engage and release a grill bar or bolt using a wedge or cam actuator of a 
particular shape operated by a pull cable. The latch members utilize a 
generally rectangular housing as a guide. 
It is, therefore, an object of the present invention to provide a quick 
release device for a window grill or the like. 
It is another object of the present invention to provide a quick release 
device for a window grill in which a cam-like or lever-like device is used 
to actuate the release mechanism. 
It is yet another object of the present invention to provide a quick 
release device for window grill in which the latch members can 
automatically adjust to inaccuracies of placement of the receiving latch 
bolt. 
These and other objects of the present invention will become manifest upon 
study of the following detailed description when taken together with the 
drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
With reference to FIG. 1, there is illustrated a partial cutaway, isometric 
view of the grill latch device 10 of the present invention comprising, 
essentially, a housing 12, in which are slidably disposed an upper latch 
member 14, a lower latch member 16 and a latch actuating member 18. 
Grill latch housing 12 comprises a generally rectangular tubular member 
having a bolt receiving opening 20 in one side thereof (see FIG. 2) of a 
large enough size to allow ample clearance for window grill bolt 22 to 
pass therethrough, taking into account any possible inaccuracies of 
manufacture. 
Upper latch member 14 comprises, essentially, an upper bolt receiving 
faceplate 30 having a bolt engaging notch 32 therein adapted to engage and 
retain the top of bolt 22. 
Upper latch member 14 also comprises a pair of first and second side panels 
34 and 36, respectively, with the bottom corner of each side panel 
proximate bolt receiving face plate 30 beveled to define generally 
straight first and second sloping edges 38 and 39, respectively. 
Lower latch member 16 comprises, essentially, a lower bolt receiving 
faceplate 40 having a bolt engaging notch 42 therein adapted to engage and 
retain the bottom of bolt 22. 
Lower latch member 18 also comprises a pair of first and second side panels 
44 and 46, respectively, with the top corner of each side panel proximate 
bolt receiving face plate 40 beveled to define generally straight first 
and second sloping edges 48 and 49, respectively. 
Latch actuating member 18 comprises, essentially, latch actuating face 
plate 50 adapted to engage or rest against lower bolt receiving face plate 
40 of lower latch member 16. 
Latch actuating member 18 also comprises a pair of first and second 
actuator wedges 52 and 54, respectively, attached to each side of latch 
actuating face plate 50 and slidably engaging the walls of housing 12. 
The sloping edges 53 and 55 of wedge 52 are adapted to slidably engage 
straight sloping edge or bevel 38 of upper latch side panel 34 and sloping 
edge or bevel 48 of lower latch side pane1 44, respectively. 
In a like manner, the sloping edges 57 and 59 of wedge 54 are adapted to 
slidably engage straight sloping side or bevel 39 of upper latch side 
panel 36 and sloping side or bevel 49 of lower latch side panel 46, 
respectively. 
Latch actuating member 18 further comprises an actuating rod 64 having one 
end attached to latch actuating face plate 50 and its other end received 
in actuating rod guide 66. 
Attached to the end of actuating rod 64 received in guide tube 66 is 
actuating cable 68. Actuating cable 68 passes out of the end of guide tube 
66 distal actuating rod 64 and is enclosed in cable guide sheath 70 to 
eventually be connected to operating handle 56 inside the building. 
A latch retainer spring 58 having one end connected to upper latch member 
14 and its lower end connected to lower latch member 16 is used to bias 
upper latch member 14 and lower latch member toward each other causing 
upper latch notch 32 and lower latch notch 42 to be maintained at their 
closest proximity. 
Thus, when grill bolt 22 is pushed through the opening defined by notches 
32 and 42, notches 32 and 34 will engage the sloping sides 24 and 26 
proximate the point of bolt 22 and be biased against bolt 22 by spring 58. 
When bolt upper notch 60 reaches bolt receiving notch 32, the bias from 
spring 58 will cause notch 32 to drop into bolt notch 60. In a like 
manner, when bolt lower notch 64 reaches bolt receiving notch 42, the bias 
from spring 58 will cause notch 42 to drop into bolt notch 64. 
With reference to FIG. 6, there is illustrated a cross-sectional, 
elevational view of a typical window grill 80 installed on the outside 
wall 82 of a building with grill latch device 10 of the present invention 
located proximate the top and bottom of frame 84 attached to wall 82. 
Operating handle 56 attached to actuating cable 68 is located inside the 
building. Cable 68 is enclosed in a molding 86. The cables from each of 
the grill latch devices 10 are attached to each other at point 88 to be 
actuated by common handle 56. Operation: 
With reference to FIG. 3, 4 and 5, there is illustrated the operating 
sequence of grill latch device 10 of the present invention. 
FIG. 3 illustrates the position of the various parts of grill latch 10 as 
grill bolt 22 enters bolt receiving opening 20 and engages upper and lower 
bolt engaging notches 32 and 42, respectively. 
FIG. 4 illustrates the positions of the various parts of grill latch device 
10 after grill bolt 22 is latched in place. 
FIG. 5 illustrates the positions of the various parts of grill latch device 
10 upon actuation of latch actuating member 18 to release grill bolt 22 
from grill latch device 10. 
It will be noted in FIGS. 3, 4 and 5, that a bolt ejection spring 72 is 
provided having one end attached to the inside of housing 12. The other 
end of bolt ejection spring 72 is adapted to engage the point of bolt 22 
to provide a constant bias against the point of bolt 22 so that, when 
released by the operation of latch actuating member 18, it is 
automatically ejected. 
This ejection function could also be accomplished by use of a coil spring 
connected to grill member 80 and biased against the outside of housing 12. 
To operate the grill latch device 10 of the present invention grill bolt 22 
is inserted between upper bolt engaging notch 32 in upper latch face plate 
30 and lower bolt engaging notch 42 in lower latch face 40 in the 
direction shown by arrow 74. 
Bolt 22 is pushed through the opening to force upper latch member 14 and 
lower latch member 16 apart as upper notch 32 and lower notch 42 slidably 
engage the sloping sides 24 and 26, respectively, as shown in FIG. 3. 
At this position, upper latch member 14 and lower latch member 16 are 
pulled apart leaving a space between upper bevel 38 and actuating wedge 52 
as well as between lower bevel 48 and actuating wedge 52. 
As grill bolt 22 continues through opening 20, the tip of bolt 22 engages 
the lower end of ejection leaf spring 72. 
As grill bolt 22 continues through opening 20, the lip of upper notch 32 
and the lip of lower notch 42 will engage upper notch 60 and lower notch 
62, respectively, in grill bolt 22 as shown in FIG. 4. Because spring 58 
biases upper latch member 14 toward lower latch member 16, the lips of 
notches 32 and 42 will engage notches 60 and 62 to retain grill bolt 22 
between upper and lower bolt receiving notches 32 and 42. 
To release grill bolt 22 from upper and lower latch members 14 and 16, 
respectively, cable 68 is pulled to cause actuating wedge 52 to move to 
the left, in FIG. 5, slidably bearing against upper bevel 38 and lower 
bevel 48 thus forcing upper latch member 14 and lower latch member 16 
apart, as shown in FIG. 5. 
When thus forced apart, bolt engaging notches 32 and 42 are also moved 
apart releasing notches 60 and 62, whereby leaf spring 72 can now force 
grill bolt to the right, as indicated by arrow 76. 
With reference to FIG. 7 there is illustrated a further embodiment of the 
latching device of the present invention. 
Grill latching device 100 of FIG. 7 is similar to grill latching device 10 
of FIGS. 1 through 6, with the exception that upper latching member 114 
and lower latching member 116 are not beveled as is the case for upper 
latching member 14 and lower latching member 16 for FIGS. 1 through 6. 
In FIG. 7, a cam-like or lever-like actuating member 118 is used which 
comprises an actuating cam or lever 152 attached to pivot pin 156 which is 
journalled to holes or bearings on opposite sides of housing 12. 
Actuating arm 158 is attached at one end to pivot pin 156 and at is other 
end to actuating cable 68. 
When actuating cable 68 is pulled, actuating arm 158 causes cam or lever 
152 to rotate and bear against the bottom edge of upper latch member 114 
and the top edge of lower latch member 116. In so doing, latch members 114 
and 116 are spread apart similar to the action of actuating wedge 18 in 
FIGS. 1 through 5. 
When the pull on cable 68 is released, the bias from spring 58 will cause 
upper latch member 114 and lower latch member 116 to move toward each 
other causing cam or lever 152 to rotate back to its rest position shown 
by the dashed lines. 
Although the present invention has been described in detail, the scope of 
this invention is not intended to be limited by the above description but 
only by the claims as indicated below.