Cap for the nozzle of a caulking cartridge

A cap to be placed on the nozzle of a caulking cartridge, for example, loaded in a caulking gun for preventing discharge from the nozzle and sealing it. The cap comprises an elongate hollow body closed at its front end and open at its back end for placement of the cap on the nozzle with the nozzle received inside the body. An elongate plug extending rearwardly within the body from the front end thereof enters the nozzle on placement of the cap on the nozzle for plugging the nozzle and preventing discharge therefrom. The cap may be clipped to the caulking gun when caulking is being dispensed from the cartridge via the gun.

BACKGROUND OF THE INVENTION 
This invention relates generally to closures for dispensing devices and 
more particularly to an improved cap for placement on the nozzle of a 
cartridge containing caulking or other hardenable and extrudable material 
to prevent discharge of caulking from the nozzle and to seal the caulking 
within the cartridge from the atmosphere to prevent it from hardening. 
Initially, the tip of the dispensing nozzle of a caulking cartridge is 
sealed or closed from the atmosphere to prevent the caulking in the 
cartridge from hardening prior to use. When application of the caulking is 
desired, the sealed tip is simply cut off, leaving an opening through 
which the caulking may be dispensed. Oftentimes, however, the contents of 
a caulking cartridge may not be entirely dispensed during a caulking 
operation, and if precautions are not taken to reseal or close the nozzle, 
the remaining caulking compound will harden (especially in the nozzle 
area) due to exposure to the atmosphere. The same problem is also 
encountered when the nozzle of a cartridge or tube of glue or other 
hardenable and extrudable substance is opened and partially used. 
Various nozzle closures have been used to avoid the above-mentioned 
problem, and reference may be made to U.S. Pat. No. 3,930,599 and U.S. 
Pat. No. Re. 18,526 for closures generally in the field of this invention. 
SUMMARY OF THE INVENTION 
Among the several objects of this invention may be noted the provision of 
an improved cap for placement on the end of a nozzle of a cartridge 
containing caulking or other hardenable and extrudable material to prevent 
further discharge of the caulking from the cartridge after a caulking 
operation has been completed and to seal the remaining caulking within the 
cartridge from the atmosphere and prevent hardening thereof; the provision 
of such a cap which is securely held on the nozzle; the provision of such 
a cap which is readily placed on and removed from the nozzle; the 
provision of such a cap which may be detachably mounted on a dispensing 
tool (oftentimes known as a gun) in which the cartridge may be held for 
dispensing of the cartridge contents; and the provision of such a cap 
which is simple in design for economical manufacture. 
Generally, a cap of this invention is adapted to be placed on the end of a 
nozzle, such as the nozzle of a cartridge adapted to be loaded into a 
dispensing tool for dispensing caulking or hardenable and extrudable 
material from the cartridge. The cap, which is adapted to seal the nozzle 
and prevent discharge therefrom, comprises an elongate hollow body closed 
at one end constituting its front end and open at its back end for 
placement of the cap on the nozzle with the nozzle inside the body. An 
elongate plug extends rearwardly within the body from the front end 
thereof and is adapted to enter the nozzle and plug it on placement of the 
cap on the nozzle for sealing the latter and preventing discharge from the 
nozzle. Means are also provided on the body for detachably mounting the 
cap on the dispensing tool when the extrudable material is being dispensed 
from the cartridge via the tool. Other objects and features will be in 
part apparent and in part pointed out hereinafter.

DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring now to the drawings, particularly to FIG. 1, a cap of this 
invention, designated in its entirety by the reference numeral 1, is shown 
on the end of a nozzle 3 of a cartridge 5 containing caulking, for 
example, although it will of course be understood that other extrudable 
and hardenable substances (e.g., glue or sealant) may also be contained 
therein. As shown, the cartridge is held in a dispensing tool 7, commonly 
known as a caulking gun. Indicated at 9 at the back of the caulking gun 7 
is a handle in the form of an L-shaped rod. As will be well known to those 
familiar with caulking guns, this handle has at its forward (left) end a 
flat circular plate (not shown) axially slideable within the cartridge 5 
for forcing the caulking out nozzle 3 for application. 
The cap, which preferably is a one-piece molded cap of a resilient 
synthetic resin material such as polyethylene, comprises an elongate 
hollow body 13, generally circular in cross-section, closed at its front 
end (left end as viewed in FIG. 5) by an end wall 15 and open at its back 
(right) end for placement of the cap on nozzle 3 with the latter received 
inside the body (see FIG. 5). Extending rearwardly (to the right) within 
body 13 from the front end wall 15 and formed integrally with the wall is 
an elongate slender plug 17 which is tapered toward its outer end. When 
the cap is placed on the nozzle of the caulking gun, this plug is adapted 
to enter into the nozzle and to close or seal it. The fact that the plug 
is tapered ensures an air-tight fit between the plug and the inside 
surface of the nozzle at the end of the nozzle, thus preventing exposure 
of the caulking in the nozzle 3 and cartridge 5 to the atmosphere. It 
should also be noted that the inside walls 19 of body 13 converge toward 
the front of the body so that on placement of the cap onto the nozzle, the 
latter becomes securely wedged between the side walls and the plug. This 
is advantageous inasmuch as the firm grip between the cap and the nozzle 
enables the cap to remain securely in place on the nozzle. 
In accordance wih this invention, cap 1 further includes a spring clip 21 
on the outside of body 13 and molded integrally therewith for mounting the 
cap on the handle 9 of the caulking gun with the longitudinal axis of the 
cap generally parallel with the handle. More particularly, this clip 21 
comprises a pair of relatively wide arms, each designated 23, extending 
one alongside the other on the outside of the body and defining an 
elongate passage 25 therebetween for receiving a relatively substantial 
length of the handle 9 of the caulking gun 7. As shown in FIG. 6, the cap 
may be detachably mounted on the handle (as when the gun is being used in 
a caulking operation) by sliding the cap down onto the handle with the 
handle received between arms 23 in passage 25. In this connection, the 
arms 23 being integral with the rest of the cap are resilient so as to 
flex apart and grip the handle when the cap is placed thereon thereby to 
securely mount the cap on the handle. The cap may be removed from the 
handle simply by sliding the cap up off the handle. It shall also be 
observed that passageway 25 decreases in size from one end to the other, 
i.e., from right to left as viewed in FIG. 5. This allows the spring clip 
21 to accommodate a wider range of handle sizes. 
To facilitate the placement of the cap on the handle and its removal 
therefrom, the end wall 15 at the front of body 3 has an annular flange 27 
at its periphery to provide an enlarged gripping surface. 
It will be apparent from the foregoing that an improved cap of this 
invention may be readily placed on and removed from the nozzle of a 
cartridge containing caulking, for example, and that it is effective in 
sealing the nozzle both to prevent further discharge of caulking from the 
cartridge after a caulking operation has been completed and to prevent the 
remaining caulking within the cartridge from hardening. Moreover, the cap 
may be readily and securely clipped onto the handle of the caulking gun 
when it is being used, thus reducing the chances that the cap will be lost 
or misplaced. In addition, the cap is simple in design for economical 
production for reduced cost. It will of course be understood that a cap of 
this invention may also be used to seal open-nozzle containers of other 
hardenable substances, such as glue or sealant. 
In view of the above, it will be seen that the several objects of the 
invention are achieved and other advantageous results attained. 
As various changes could be made in the above construction without 
departing from the scope of the invention, it is intended that all matter 
contained in the above description or shown in the accompanying drawings 
shall be interpreted as illustrative and not in a limiting sense.