Joint assembly of horizontally opposed curtain wall units

In a joint assembly of two adjacent curtain wall units, an exterior gasket is divided into a pair of interfitting male and female halves carried by respective exterior parts of the adjacent vertical frame members. An interior gasket mounted between opposed interior parts of the adjacent vertical frame members has opposite edge portions each fitted in a recess of the respective interior part and projecting beyond the interfitting edges of the male and female gasket halves. In installation, one of the opposite edge portions of the interior gasket can be observed by the workman's eye through a gap between the male and female gasket halves while it is being inserted into the recess of the corresponding interior part.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a curtain wall construction composed of a 
plurality of curtain wall units arranged in rows and colums, and more 
particularly to a joint assembly of an adjacent pair of horizontally 
opposed curtain wall units. 
2. Description of the Prior Art 
A known joint assembly between an adjacent pair of horizontally opposed 
curtain wall units, as disclosed in Japanese Patent Laid-Open Publication 
(Kokai) No. 57-161434, comprises an interior gasket and an exterior 
sealing strip, both mounted between opposed vertical frame members of the 
two adjacent curtain wall units. The interior gasket has opposite edge 
portions respectively fitted in opposed interior recesses of the adjacent 
vertical frame members, while the exterior sealing strip is carried by one 
of the adjacent vertical frame members and extends into an exterior recess 
of the other vertical frame member. 
With this prior arrangement, when one curtain wall unit is joined with the 
previously installed curtain wall unit, the interior gasket and the 
exterior sealing strip are received respectively in the interior and 
exterior recesses of the adjacent vertical frame members at the same time. 
That is, the exterior sealing strip would serve as a blind so that the 
workman cannot observe the interior gasket from the exterior while it is 
being fitted in the interior recesses, causing inaccurate and non-easy 
joining of the adjacent curtain wall units. Further, after the adjacent 
curtain wall units have been joined together, the sealing strip cannot be 
removed and, therefore, the workman cannot ascertain from the exterior 
whether the interior gasket is properly received in the opposed interior 
recesses of the vertical frame members. 
SUMMARY OF THE INVENTION 
In the present joint assembly of two adjacent curtain wall units, an 
exterior gasket is divided into a pair of interfitting male and female 
halves carried by respective exterior parts of the adjacent vertical frame 
members. An interior gasket mounted between opposed interior parts of the 
adjacent vertical frame members has opposite edge portions each fitted in 
a recess of the respective interior part and projecting beyond the 
interfitting edges of the male and female gasket halves. In installation, 
one of the opposite edge portions of the interior gasket can be observed 
by the workman's eye through a gap between the male and female gasket 
halves while it is being inserted into the recess of the corresponding 
interior part. 
It is therefore an object of the present invention to provide a joint 
asseambly of two adjacent curtain wall units which enables the workman to 
observe from the exterior whether opposite edge portions of an interior 
gasket are properly fitted in opposed recesses of the opposed interior 
parts not only during the joining of the adjacent curtain wall units, but 
also after the latter have been joined. 
Another object of the invention is to provide a joint assembly with which 
two adjacent curtain wall units can be joined with each other along their 
opposed vertical frame members easily with adequate fluid-tightness. 
Many other advantages, features and additional objects of the present 
invention will become manifest to those versed in the art upon making 
reference to the detailed description and the accompanying drawings in 
which a preferred embodiment incorporating the principles of the present 
invention is shown by way of illustrative example.

DETAILED DESCRIPTION 
FIG. 1 illustrates a curtain wall construction composed of a plurality of 
curtain wall units A mounted on a building in a checkerboard pattern. Each 
of the curtain wall units A comprises a pair of vertical frame members 1, 
1 and a pair of upper and lower horizontal frame members 2, 3 joined with 
the vertical frame members 1, 1 end to end to provide a rectangular frame. 
This rectangular frame is divided, by a mullion and two transoms, into six 
smaller rectangles of different sizes to support two lights 4a, 4a, a 
fixed double-glazed panel 4b, a pivotable double-glazed panel 4b, and two 
insulating panels or glass panes 4c, 4c. 
As shown in FIG. 2, an adjacent pair of horizontally opposed curtain wall 
units A.sub.1, A.sub.2 is joined with each other along their opposed 
vertical frame members 1, 1 in a manner described below. Each of the 
vertical frame members 1 includes a pair of interior and exterior parts 
10, 11 interconnected by a screw 15, with a pair of first and second 
spacers 13, 14 of thermally insulating material sandwiched between the 
interior and exterior parts 10, 11. Each of the interior and exterior 
parts 10, 11 has along the entire length thereof a laterally opening 
vertical recess 16, 17. 
A pair of parallel interior and exterior vertical gaskets 18, 19 is mounted 
between the adjacent vertical frame members 1, 1 so as to define 
therebetween a vertical space S. The interior vertical gasket 18 has 
opposite edge portions fitted respectively in the recesses 16, 16 of the 
interior parts 10, 10 of the adjacent vertical frame members 1, 1. 
The exterior vertical gasket 19 is composed of a pair of interfitting male 
and female halves 19A, 19B. The male gasket half 19A has a base fitted in 
the recess 17 of one of the opposed exterior parts 11 and has along its 
free edge a longitudinal tongue 21. The female gasket half 19B has a base 
fitted in the recess 17 of the other of the opposed exterior parts 11 and 
has along its free edge a longitudinal groove 20 receiving the tongue 21 
of the male gasket half 19A, the depth of the groove 20 being smaller than 
the depth of the recess 16 of each interior part 10. Thus the interior and 
exterior vertical gaskets 18, 19 jointly serve to provide a fluid-tight 
sealing between the adjacent pair of horizontally opposed curtain wall 
units A.sub.1, A.sub.2. 
An auxiliary seal member 23 has a base carried by one of the adjacent 
interior parts 10, and a free edge contacting the other of the adjacent 
interior parts 10. 
For assembly, as shown in FIG. 3, the female half 19B of the exterior 
gasket 19 is fitted in the recess 17 of the exterior part 11 of the left 
curtain wall unit A.sub.1 that has been previously installed. The male 
half 19A of the exterior gasket 19 is fitted in the recess 17 of the 
exterior part 11 of the right curtain wall unit A.sub.2 that is to be 
joined with the left curtain wall unit A.sub.1, and the right edge portion 
of the interior gasket 18 is inserted in the recess 16 of the interior 
part 10 of the right curtain wall unit A.sub.2. 
Subsequently, the right curtain wall unit A.sub.2 is positioned in 
horizontal alignment with the left curtain wall unit A.sub.1, as shown in 
FIG. 4, and is then moved toward the left curtain wall unit A.sub.1 to the 
position of FIG. 3 in which the left edge portion of the interior gasket 
18 is disposed close to the recess 16 of the interior part 10 of the left 
curtain wall unit's vertical frame member 1. With continued leftward 
movement of the right curtain wall unit A.sub.2, the left edge portion of 
the interior gasket 18 is inserted into the recess 16 of the interior part 
10 of the left curtain wall unit's vertical frame member 1, and thereafter 
the tongue 21 of the male gasket half 19A is inserted into the groove 20 
of the female gasket half 19B. Before the insertion of the tongue 21, the 
left edge portion of the interior gasket 18 can be observed by the 
workman's eye from the exterior through a gap between the male and female 
gasket halves 19A, 19B until it is inserted into the recess 16 of the 
interior part 10 of the left curtain wall unit's vertical frame member 1, 
because the left edge 18a of the interior gasket 18 projects beyond the 
distal edge 21a of the male gasket half's tongue 21 by a predetermined 
length L in an edgewise direction of the curtain wall units A.sub.1, 
A.sub.2. Preferably, the length L is smaller than half the length of the 
interior gasket 18 and larger than the length of each edge portion of the 
interior gasket 18. 
By this observing, it is possible to insert the left edge portion of the 
interior gasket 18 in the recess 16 of the interior part 10 of the left 
curtain wall unit's vertical frame member 1 without difficulty, thus 
causing accurate and easy joining of the right and left curtain wall units 
A.sub.2, A.sub.1. 
Still, after the two adjacent curtain wall units A.sub.1, A.sub.2 have been 
joined, by removing the screws 15 to enable the removal of the male and 
female gasket halves 19A, 19B, or by pushing the same interiorly, to 
provide a gap in the exterior gasket 19, the workman can ascertain not 
only whether the opposite edge portions of the interior gasket 18 are 
properly fitted in the opposed recesses 16, 16 of the adjacent interior 
parts 10, 10, but also whether the first and second spacers 13, 14 are 
good or bad. 
The interfitting tongue 21 and groove 20 of the male and female gasket 
halves 19A, 19B jointly serve as a throating along which rainwater would 
run down smoothly. 
In an alternative way, the female gasket half 19B and the interior gasket 
18 may be attached respectively to the exterior and interior parts 11, 10 
of the previously installed left curtain wall unit A.sub.1, with the male 
gasket half 19A attached to the exterior part 11 of the free right curtain 
wall unit A.sub.2. Then the right curtain wall unit A.sub.2 is moved 
toward the left curtain wall unit A.sub.1 for joining therewith, at which 
time the right edge portion of the interior gasket 18 can be observed by 
the workman's eye from the exterior through a gap between the male and 
female gasket halves 19A, 19B until it is almost fully inserted in the 
recess 16 of the interior part 10 of the right curtain wall unit A.sub.2. 
Although various minor modifications may be suggested by those versed in 
the art, it should be understood that I wish to embody within the scope of 
the patent warranted hereon, all such embodiments as reasonably and 
properly come within the scope of my contribution to the art.