Window stay

A window stay for the support of a window glass for use in vehicles, with a window frame and a glass retainer firmly secured to the window frame with the peripheral edge portion of the window glass sandwiched fluid-tight between the window frame and the glass retainer. An elastic cushioning strip encircles the peripheral edge portion of the window glass and is held in position between the window frame and the glass retainer during assembly of the peripheral edge portion of the window glass in the sandwich. To avoid relative displacement of the glass retainer, a rim projection is integrally formed with the window frame, thereby permitting the glass retainer to resist the reactive force exerted by the compressed elastic cushioning strip.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention generally relates to a window stay and, more 
particularly, to a framework for the support of a panel member such as a 
glass plate to make up window. 
2. Prior Art 
Windows, particularly those used in vehicles such as trains, automobiles or 
the like, have stringent requirements for fluid tightness to avoid 
possible intrusion of rain and/or dust; resistance to vibration; 
resistance to shock due to impingement of solids on the glass plate; and 
safety. In view of this, window stays generally employed nowadays comprise 
a metallic window frame which is secured to the wall structure and an 
elastic cushioning strip encircling the peripheral edge of the glass plate 
and held in position between the window frame and the glass retainer to 
avoid direct contact between the glass plate and either the window frame 
or the glass retainer. The elastic cushioning strip is either a strip made 
of elastic shock absorbing material or a strip made by drying or curing a 
filler-sealant which has been applied during the fabrication of the 
window. The compression of the strip sandwiched between the window frame 
and the glass retainer results in a reactive force tending to restore the 
strip to its original shape which provides both fluid tightness and 
vibration resistance. 
One example of a prior art window stay so far found to be closest to the 
present invention is illustrated in FIG. 1 of the accompanying drawings. 
FIG. 1 shows a cross-sectional representation of the prior art window stay 
taken in a direction generally perpendicular to the plane of the glass 
plate. The wall structure 1, for example, a double-paneled side wall of a 
train car, has a window frame 2 rigidly secured to it. An elastic 
cushioning strip 3 has a groove of a width generally equal to or slightly 
smaller than the thickness of the glass plate 4. The groove receives the 
glass plate 4. The elastic cushioning strip 3 is mounted in window frame 2 
with its one side face held in contact with the peripheral flange 2a of 
window frame 2; and its other side in contact with the glass retainer 5 is 
secured to window frame 2 by means of a plurality of set screws 6 to press 
the peripheral edge of the glass plate 4 against the peripheral flange 2a. 
This prior art window stay is so designed that when the set screws 6 are 
tightened in the assembly described above, the elastic cushioning strip 3 
is in a state of compression which exerts a reactive force tending to 
restore the elastic cushioning strip to its original shape. The effect of 
this reactive force is to tighten all contact seals permitting the window 
as a whole to exhibit fluid tightness, resistance to vibration and 
resistance to shock all at one time. 
In the prior art window stay of the construction described above, the 
extent to which the elastic cushioning strip 3 is compressed depends on 
the extent to which the set screws 6 are tightened. Because of this, the 
set screws 6 used have to be of a type having a rigid and robust threaded 
shank; at the same time, the glass retainer 5 must have a relatively large 
cross-sectional area to withstand the reactive force. In addition, the set 
screws 6 must be placed at an angle relative to each other as shown in 
FIG. 1. Accordingly, a relatively large space is required for the mounting 
of the prior art window stay and the mounting procedures are complex. 
These disadvantages and inconveniences in the prior art window stay exist 
because only the glass retainer 5 and the set screws 6 withstand the 
reactive force exerted by the compressed elastic cushioning strip 3. If 
one or more extra members were utilized in cooperation with the glass 
retainer 5 and the set screws 6 to withstand the reactive force, the 
above-described disadvantages and inconveniences would be obviated. 
Furthermore, the prior art window stay under discussion makes use of the 
elastic cushioning strip 3 for the purpose of permitting the window stay 
as a whole to exhibit both the fluid tightness and shock absorbing 
properties. It has, however, been found that sole use of the elastic 
cushioning strip 3 is not effective in avoiding any possible separation 
from both the window frame 2 and the elastic cushioning strip 3 of 
fragments of the glass plate 4 when the latter has been cracked owing to, 
for example, collision with a stone. If fragments of the broken glass 
plate 4 separate, some train passengers seated adjacent to the window will 
be subjected to cuts and/or other accidents will occur. This dangerous 
possibility may be eliminated if the peripheral edge of the glass plate is 
bonded to the window frame 2 by the use of a bonding agent. 
It is well known that vehicle front windows are generally subjected to a 
safety test during which they are struck by concrete blocks, one at a 
time. The requirements for passing this test include the provision that, 
even though the window glass cracks or is depressed, fragments of the 
broken window glass must not scatter into the interior of the vehicle. In 
anticipation of these safety requirements, it is not only necessary to 
improve the physical strength of each of the component parts of the glass 
window such as the glass plate and the window frame, but also to provide 
means for retaining the glass plate in the window frame and avoiding any 
separation between them. In other words, any relative movement between the 
glass plate and elastic cushioning strip must be substantially eliminated 
or minimized to keep the strip in tight contact with the peripheral edge 
of the glass plate. Then, even if the glass plate deforms as a result of 
being impacted by rigid foreign matter, the peripheral edge of the glass 
plate will stay in the window frame. 
In spite of the foregoing consideration, the prior art window stay makes 
use of the elastic cushioning strip only for the purpose of providing 
fluid tightness and cushioning between the glass plate and the window 
frame, permitting relative slip between them to occur. Therefore, the 
prior art window stay has the disadvantages that the glass plate is 
insufficiently retained in the window frame and also in that the 
resistance to impact is low. 
SUMMARY OF THE INVENTION 
Accordingly, the present invention has been developed to substantially 
eliminate the above described disadvantages and inconveniences inherent in 
the prior art window stay. Its essential object is to provide an improved 
window stay wherein the transmission of the reactive force produced by the 
compressed elastic cushioning strip to the glass retainer, particularly to 
the set screws or bolts, is advantageously minimized. 
Another important object of the present invention is to provide an improved 
window stay of the type referred to above, wherein for securing the glass 
retainer to the window frame set bolts with relatively small diameter 
shanks are used. These set bolts require less space and also improve the 
outer appearance of the window. 
A further object of the present invention is to provide an improved window 
stay with fewer fitting and mounting procedures but of increased 
effectiveness. 
A still further object of the present invention is to provide an improved 
window stay, wherein the glass retainer can be accurately positioned 
around the periphery of the panel member such as a glass plate while the 
reactive force exerted by the compressed elastic cushioning strip is 
transmitted substantially uniformly to impart high fluid tightness to the 
resulting window. 
A still further object of the present invention is to provide an improved 
window stay wherein the glass retainer is designed to apply a compressive 
force uniformly to the elastic cushioning strip to allow the latter to 
exert a reactive force by which the glass plate can be firmly retained in 
position in the window frame. 
A yet still further object of the present invention is to provide an 
improved window stay in which the glass plate can be firmly retained in 
position between the window frame and the glass retainer with no 
substantial possibility of any glass fragments being separated and 
scattered, and hence, a window which has a relatively high impact strength 
.

DETAILED DESCRIPTION OF THE INVENTION 
Before describing the present invention, it is to be noted that like parts 
are designated by like reference numerals throughout the accompanying 
drawings. 
Referring first to FIGS. 2 and 3, a window stay embodying the present 
invention is a unitary structure comprising a panel member, for example, a 
glass plate 4, having its peripheral edge portion supported against a 
window frame 10 by means of a glass retainer 12 connected to the window 
frame 10. This unitary window structure is mounted to a wall structure 
partially shown by 16 in Fig.3 which has a window defining opening 17 
provided therein in a manner which will become clear from the subsequent 
description. 
The glass plate 4 is generally rectangular in shape and, hence window frame 
10, glass retainer 12 and window defining opening 17 in wall structure 16 
are correspondingly rectangular, but the invention is not limited to this 
shape. 
As best shown in FIG. 3, the window frame 10 generally comprises a web 10b 
of predetermined width greater than the thickness of the glass plate 4 
used, an abutment flange 10a integral with and extending in one direction 
from one side edge of the web 10b generally at right angles thereto so as 
to lie parallel to glass plate 4, and a mounting flange 10c integral with 
and extending in the opposite direction from the opposite side edge of the 
web 10b which has a shape similar to the mathematical square root symbol. 
Adjacent to the joint between the opposite side edge of the web 10b and 
the mounting flange 10c, the window frame 10 is integrally formed with a 
rim 13a protruding a slight distance from window frame 10 in the same 
direction in which the abutment flange 10a extends so as to define a 
generally right-angled bank 13 between it and the web 10b. On the other 
hand, the glass retainer 12 is of generally L-shaped cross-section and 
comprises a clamping flange 12x and a flank 12y which are disposed to lie 
generally parallel to the abutment flange 10a and the web 10b of the 
window frame 10 when the glass retainer 12 is coupled to the window frame 
10 to make up the unitary window structure in a manner to be described 
later. 
The window stay according to the present invention makes use of a generally 
L-sectioned elastic cushioning strip 11 preferably made of rubber material 
in the form of a substantially endless loop with a circumference 
corresponding to the circumference of the glass plate 4. 
To make up the unitary window structure, the inside surface of the abutment 
flange 10a of the window frame 10, which engages one peripheral surface 
area 4a of the glass plate 4, is covered, or otherwise bonded, to an 
elastic adhesive strip 14 having a cushioning property. After the adhesive 
strip 14 has been applied to the abutment flange 10a in the manner 
described above, the glass plate 4 is mounted in the window frame 10 with 
its peripheral surface area 4a kept in contact with the elastic adhesive 
strip 14. The elastic cushioning strip 11 is then mounted 
circumferentially around the glass plate 4 to permit it to contact and 
cover both the opposite peripheral surface area 4b of the glass plate 4 
and the peripheral cut face 4c of the glass plate 4. Preferably, the 
elastic cushioning strip 11 is undersized so that when it is mounted 
circumferentially of the glass plate 4 in the manner as previously 
described, it can be slightly elongated and, hence, precompressed to avoid 
its separation from the glass plate 4 during the mounting procedure. 
Thereafter, the glass retainer 12 is fitted in the window frame 10 with 
its clamping flange 12x and flank 12y held in abutment with the elastic 
cushioning strip 11 and the web 10b, respectively. As the final step of 
the mounting procedure, a number of fastening bolts 15 are passed through 
the flank 12y and then through the web 10b and are fixed in position by 
associated nuts 15a positioned on one side of the web 10b opposite the 
glass retainer 12, thereby completing the unitary window structure. 
The unitary window structure fabricated as described above is then mounted 
in the window defining opening 17 in the wall structure 16 with the 
mounting flange 10c firmly connected to the wall structure 16 by means of 
set screws or bolts 18 threaded through the mounting flange 10c into the 
wall structure 16. Alternatively, it may be possible to make up the 
unitary window structure by first securing the window frame 10 to the wall 
structure 16, then mounting the glass plate 4 in the window frame 10, and 
finally setting the glass retainer 12 in the manner described above. 
It is to be noted that, when the glass retainer 12 is set in position on 
the window frame 10 as best shown in FIG. 3, both the elastic adhesive 
strip 14 and the elastic cushioning strip 11 are inwardly compressed to 
provide fluid tightness. This inward compression produces a reactive force 
as in the case of the elastic cushioning strip employed in the prior art 
window stay. This reactive force acts, in the instance of the present 
invention, on the glass retainer 12 to displace the latter in a direction 
away from the abutment flange 10a of the window frame 10. However, because 
of the provision of the rim 13a defining the right-angled bank 13 in which 
the free side edge of the flank 12y is seated, no actual displacement of 
the glass retaining member 12 takes place. 
The elastic adhesive strip 14 applied to the abutment flange 10a of the 
window frame 10 is preferably made of a fabric strip having its opposite 
surfaces coated with rubber adhesive material. By way of example, a 
commercially available double-sided adhesive tape comprising a fabric 
substrate, such as manufactured and sold by Nitto Denko K. K. of Japan 
under the trade name "Nitto Double-sided Adhesive Tape #525", may be 
employed as the elastic adhesive strip 14 for the purpose of the present 
invention. In practice, it is preferred to use two overlapping layers of 
the double-sided adhesive tape for the elastic adhesive strip 14. In any 
event, it has been found that the above-mentioned commercially available 
double-sided adhesive tape is most suited from the stand points of 
cushioning effect and bonding power. 
The glass retainer 12 shown in FIGS. 2 and 3 is made up of two split 
sections 12a and 12b of identical construction each being generally 
U-shaped in configuration. In other words, the glass retainer 12 employed 
in the embodiment shown in FIGS. 2 and 3 is of two-piece construction. 
However, it may be of one-piece construction, i.e., it may be employed in 
the form of a continuous rectangular glass retaining member as shown in 
FIG. 9. Where it is desired to employ a continuous glass retainer 12 as 
shown in FIG. 9, it is preferably slightly oversized so that, when secured 
firmly to the window frame 10 by means of the bolts and nuts 15 and 15a in 
the manner described above in connection with the embodiment of FIGS. 2 
and 3, both the elastic adhesive strip 14 and the elastic cushioning strip 
11 can be inwardly compressed to accommodate the difference in dimension 
between the slightly oversized glass retainer 12 and the circumference of 
rim 13a in the window frame 10. 
In FIG. 9, the slightly oversized glass retainer 12 is somewhat exaggerated 
as shown by the chain lines. In any event, the glass retainer 12 according 
to the embodiment of FIG. 9 has the advantage that it can be set by a 
simple fitting procedure compared with that according to the embodiment of 
FIGS. 2 and 3. 
Moreover, the glass retainer 12 used in the practice of the present 
invention is not always limited to either a one-piece or two-piece 
construction. The embodiment of FIG. 4 shows a two-piece construction (as 
does the embodiment of FIGS. 2 and 3) with the two split sections 12a' and 
12b' sized so that the glass retainer 12 as a whole can be slightly 
oversized relative to the circumference of the rim 13a by, for example, a 
few millimeters when the circumference of rim 13a is 500 mm. In the 
example shown in FIG. 4, after one of the split sections 12a' or 12b', for 
example, the section 12a', has been secured to the window frame 10 by 
means of the bolts and nuts 15 and 15a and the other section 12b' has not 
yet been secured, but merely fitted to the window frame 10, at least one 
end of the other section 12b' will not be in end-to-end contact with the 
adjacent end of section 12a' as indicated by the chain-lined circle in 
FIG. 4. However, it can be brought into end-to-end abutment with the 
adjacent end of section 12a' when section 12b' and window frame 10 are 
fastened together by the bolts and nuts 15 and 15a with the elastic 
cushioning strip 11 consequently compressed inwardly, causing the glass 
plate 4 to be retained firmly to produce a fluid-tight window stay. 
Where a relatively high rigidity is required in the glass retainer 12, a 
four-segment glass retainer may be employed as shown in FIGS. 5 and 6 
where the glass retainer 12 comprises four segments 12b1, 12b2, 12b3, 
12b4, all generally L-shaped and, when combined together, constituting a 
glass retainer 12 of generally rectangular configuration. In the 
embodiments of FIGS. 5 and 6 the four segments 12b1 through 12b4, each 
having a cross-section similar to that shown in FIG. 3, are preferably so 
sized that the glass retainer 12 as a whole can be oversized as described 
above in connection with any one of the embodiments of FIGS. 4 and 9. 
It should be noted that the embodiment of FIGS. 5 and 6 differ from each 
other in that while the glass retainer 12 in the embodiment of FIG. 5 is 
split in a direction at right angles to the longitudinal axis of each side 
of the rectangular shape to provide the four segments 12b1 through 12b4, 
the glass retainer 12 in the embodiment of FIG. 6 is split in a direction 
diagonal to each side of the rectangular shape to provide the four 
segments 12b1 through 12b4. 
In particular, in the embodiment shown in Fig.6, when and after one of the 
segments, for example the segment 12b1, has been secured to window frame 
10 by means of the bolts and nuts 15 and 15a, and when the next adjacent 
segment 12b2 is to be secured to the window frame 10 by means of bolts and 
nuts 15a and 15b, one inclined end face Fa of the segment 12b1 serves to 
guide the adjacent inclined end face Fb of the segment 12b2 to allow the 
latter to wedge into the correct position when one of the bolts 15 which 
is adjacent to the inclined end face Fb of the segment 12b2 is fastened by 
turning the associated nut 15a in the manner shown in Fig.7. 
In the embodiment shown in FIG. 8, the glass retainer 12 is similar to that 
employed in the embodiment shown in and described with reference to FIGS. 
5 and 6 in that it comprises the four segments. However, two of the four 
segments 12c1, 12c2, 12c3 and 12c4 (though the segment 12c4 is not 
illustrated in FIG. 8), that is, segments 12c1 and 12c3 which are to be 
positioned on the extreme sides of the window stay, are generally U-shaped 
while the remaining segments 12c2 and 12c4 are straight. In addition, each 
of the straight segments 12c2 and 12c4, which are to be positioned at the 
upper and lower extremities of the window stay, respectively, has its 
opposite ends inclined so as to converge at a point outside the window 
structure. Thus, after the side segments 12c1 and 12c3 have been secured 
to the window frame 10, the straight segments 12c2 and 12c4 are secured to 
frame 10 by being wedged between the opposite ends of the side segments 
12c1 and 12c3, as shown, as the bolts 15 are fastened. Thus, when and 
after the straight segments 12c2 and 12c4 have been secured to the window 
frame 10 in the manner described above, the side segments 12c1 and 12c3 
are biased in opposite directions away from each other to compress 
adjacent portions of the elastic cushioning strip 11 in contact with them. 
While the individual preferred embodiments of the present invention have 
been described herein, it has been found that, when the window stay 
acdording to the embodiments shown in FIGS. 2 and 3 which is supporting a 
laminated glass plate which is made of a transparent reinforcement sheet, 
0.5 mm in thickness, sandwiched tightly between a pair of glass plates, 
one 10 mm in thickness and the other 3mm in thickness, was tested by 
dropping a concrete block of 12.28 kg in weight onto the glass plate from 
a specific height so as to simulate a speed of 64.4 km/hr, the window stay 
met the previously described requirements without the glass fragments 
separating or scattering although the glass plate was depressed. 
Although the present invention has been fully described in connection with 
the various preferred embodiments thereof with reference to the 
accompanying drawings, it is to be noted that numerous changes and 
modifications can be readily conceived by those skilled in the art upon 
reading of the disclosure herein without departing from the spirit and 
scope of the present invention. By way of example, although in describing 
each of the preferred embodiments of the present invention, the glass 
plate and the associated component parts of the window stay have been 
shown and described as having a generally rectangular shape, they may have 
any other shape, for example, a square shape, a circular shape or an oval 
shape. 
Accordingly, unless they depart from the scope of the present invention as 
defined by the appended claims, they should be construed as included 
therein.