Liquid cartridge storage case for use with liquid dipenser

A liquid cartridge storage case is used in connection with a plunger valve liquid dispenser to provide simplified and accurate control of liquid dispensing from a commercially available liquid cartridge, along with reduced downtime. The storage case includes a lower body section to which a commercially available liquid cartridge threadably mounts. Threading of the cartridge to the lower body section pierces a bottom membrane of the cartridge to allow liquid from the cartridge to flow into an internal passage in the lower body section. The internal passage communicates with a passageway of the dispenser through which liquid flow is controlled, via the plunger valve, for dispensing out of a nozzle at one end thereof. Pressurized air supplied from an external source to the inside of the case causes a cartridge wall opposite the pierced membrane to move toward the pierced membrane, thereby forcing liquid under pressure from the cartridge and into the dispenser. An additional liquid cartridge storage case may be connected to the liquid dispenser in parallel, thereby to allow dispensing from a liquid cartridge in one of the storage cases while the spent liquid cartridge of the other case is being replaced.

FIELD OF THE INVENTION 
This invention relates to a liquid dispensing apparatus for dispensing 
liquid from commercially available liquid cartridges. 
BACKGROUND OF THE INVENTION 
Many commercially available liquids for dispensing, such as adhesives, 
sealants, etc. are dispensed from commercially available liquid 
cartridges. Even liquids such as paints can be dispensed from such liquid 
cartridges. Usually dispensing from these liquid cartridges is manually 
controlled, as by a commercial handgun. However, in many dispensing 
operations, the manual control of the liquid dispensed from a liquid 
cartridge via a normally operated handgun is not accurate enough. Thus, 
while the wide commercial availability of various liquids in easy-to-use 
liquid cartridges facilitates economic liquid dispensing for multiple 
commercial applications, there exists a need for greater precision and 
accuracy in dispensing liquid from such cartridges. In addition, it is 
desirable to provide increased accuracy and control in a simple and 
economical manner, so that the ease of liquid cartridge use is not 
defeated by the manner of dispensing. Stated another way, it is desirable 
to achieve improved control of liquid dispensing from a commercially 
available liquid cartridge in a manner which is simple, practical and 
economical. 
Because many applications for dispensing liquid from liquid cartridges 
require the use of multiple cartridges, it is also desirable to minimize 
downtime associated with replacing a spent cartridge with a new cartridge. 
It is an object of this invention to increase the accuracy and control of 
liquid dispensing from a commercially available liquid cartridge without 
compromising practicability, simplicity and economy. 
It is another object of the invention to improve control over liquid 
dispensing from a commercially available liquid cartridges while at the 
same time reducing downtime associated therewith. 
SUMMARY OF THE INVENTION 
The above-stated objectives are achieved by using a cylindrical cartridge 
storage case in combination with a plunger valve liquid dispensing gun to 
accurately dispense pressurized liquid. The cartridge storage case 
threadably receives the liquid cartridge in a manner which automatically 
supplies liquid from the cartridge to the dispensing gun. The cartridge 
storage case also operatively connects to a pressure source that supplies 
pressurized air to the inside of the case to force liquid under pressure 
from the liquid cartridge into the dispensing gun. 
The simple and economical design of the cartridge storage case allows 
liquid cartridges to be easily placed therein, used and subsequently 
removed, thereby facilitating delivery of pressurized liquid from a liquid 
cartridge to the dispensing gun. Additionally, by using a plunger valve 
dispensing gun in combination with this cartridge storage case, increased 
dispensing accuracy is achieved without any loss of convenience. 
To further reduce downtime and to provide a continuous supply of 
pressurized liquid to the dispensing gun, one or more additional liquid 
cartridge storage cases may be connected to the dispensing gun in 
parallel, thereby to eliminate downtime associated with replacing a spent 
liquid cartridge with a new liquid cartridge. 
According to a preferred embodiment of the invention, a liquid cartridge 
storage case includes threadably connected first and second body sections 
which form a cylinder. The first or bottom body section includes an 
internally threaded recessed portion adapted to receive an externally 
threaded first end of a liquid cartridge. Inside the recessed portion, the 
bottom section has a protrusion which extends upwardly, and the protrusion 
has an angled surface. An internal passage extends along the protrusion, 
through the bottom section and terminates at an outlet on the external 
surface of the bottom section. Upon threaded connection of a liquid 
cartridge to the bottom section, the angled surface of the protrusion 
pierces a bottom membrane of the liquid cartridge, thereby permitting the 
flow of liquid from the cartridge through the passage to a radial inlet 
passage of the dispensing gun, which is mounted in fluid communication 
therewith. A one-way valve is located along the passage, within the body 
section, to prevent reverse flow back through the passage. 
The second or top body section of the cylindrical case includes an opening 
adapted receive a tube through which pressurized air is supplied from a 
pressurized air source. The pressurized air supplied to the storage case 
acts upon a movable end wall at a second end of the liquid cartridge, 
opposite the first end, thereby moving the end wall of the liquid 
cartridge toward the hub at the first end and forcing liquid from the 
cartridge under pressure to the dispensing gun. 
Thus, the cylindrical cartridge storage case of this invention provides for 
easy insertion, use and removal of a liquid filled cartridge, while the 
dispensing gun associated therewith provides accuracy in dispensing the 
contents of the liquid cartridge. Because of the simplicity in the design 
of the cartridge storage case, minimal time is spent preparing to dispense 
the contents of the liquid filled cartridge. 
Additionally, to further reduce downtime, an additional liquid cartridge 
storage case may be connected to the dispensing gun in parallel to provide 
continuous dispensing via use of one of the liquid filled cartridges in 
one storage case during removal of a spent cartridge from the other 
storage case. 
These and other features of the invention will be more readily understood 
in view of the following detailed description and the drawing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
The FIGURE shows an apparatus for liquid dispensing 10 which includes a 
liquid cartridge storage case 12 in combination with a liquid dispenser or 
gun 14 in accordance with a preferred embodiment of the invention. The 
liquid dispenser 14 includes an electrical controller 16 which controls 
operation of a solenoid 18 to intermittently raise and lower a plunger 
valve 20 to open and close, respectively, a passageway 22 through the 
dispenser 14. The passageway 22 terminates in a nozzle 24, and the FIGURE 
shows a liquid drop 26 as it is dispensed from nozzle 24 upon raising of 
the plunger valve 20. 
The liquid cartridge storage case 12 is adapted to receive and hold a 
commercially available liquid cartridge, designated by reference numeral 
28. The storage case 12 includes a first lower body section 30 and a 
second upper body section 32 threadably connected thereto. The liquid 
cartridge 28 includes an externally threaded lower hub 34 which threadably 
connects to a complementarily internally threaded, recessed portion 33 of 
the lower body section 30, thereby connecting the case 12 and cartridge 28 
along a common longitudial axis. An outer portion of the bottom of the 
liquid cartridge 28 is supported within lower body section 30 by an O-ring 
35. 
When a liquid cartridge 28 is threadably secured to lower body section 30, 
a bottom membrane 36 of the cartridge 28 is pierced by an angled upper 
edge 37 of a protrusion 38 which extends upwardly from lower body 30, 
within recessed portion 33. A passage 40 extends through the protrusion 38 
and downwardly through lower body section 30, and the passage 40 makes a 
right angle turn and extends to the outside of lower body section 30 to 
connect with a radial passage 42 in the liquid dispenser 14. A one way 
valve 44 is housed within lower body section 30, along passage 40, to 
prevent back flow of liquid along passage 40. 
A tube 46 threadably connects to a top end of the upper body section 32 of 
the storage case 12. This tube 46 is in fluid communication with the 
inside of the storage case 12 via an opening 48 in upper body section 32. 
Pressurized air is supplied to tube 46 via a pressurized gas tank 50. Gas 
flow along tube 46 is controlled by a regulator 52 and a solenoid valve 
54, operation of which is controlled by an electrical controller 56. The 
pressurized air supplied to the inside of storage case 12 through opening 
48 causes a movable top end 58 of the liquid cartridge 28 to move 
downwardly, as shown by directional arrows 60, thereby forcing liquid from 
the cartridge 28 and through passage 40, past valve 44 and into passageway 
22 of the liquid dispenser 14, whereupon the liquid is dispensed in 
accordance with operation of the plunger valve 20. 
Use of this liquid cartridge storage case 12 in combination with the liquid 
dispenser 14 enables liquid to be dispensed from commercially available 
liquid cartridges 28 with the accuracy and control provided by a 
plunger-type dispensing gun 14. Additionally, the case 12 provides simple 
insertion, use and removal of a liquid cartridge 28, thereby reducing set 
up and downtime. 
According to another aspect of the invention, one or more additional liquid 
cartridge storage cases may be connected to the dispenser 14 to further 
eliminate downtime associated with substituting a new cartridge 28 for a 
spent cartridge 28. Accordingly, the FIGURE shows, in phantom, an 
additional liquid cartridge storage case 12a and an additional liquid 
cartridge 28a, both with structural components designated by reference 
numerals that end in "a" but which otherwise correspond to structural 
components bearing the same reference numerals without the "a". If 
desired, additional cases may also be connected to gun 14 in parallel. 
According to this embodiment, when cartridge 28 is replaced, by unthreading 
upper body section 32 from lower body section 30, removing cartridge 28 
and replacing it with a new cartridge, and then threading upper body 32 
into lower body 30 again, controller 56 operates solenoid valve 54 to 
divert pressurized air from case 12 to case 12a. In this way material is 
dispensed from cartridge 28a, while cartridge 28 is being replaced so that 
material can continue to be dispensed through nozzle 24 with no downtime. 
In sum, the invention provides a simple and economic structure for 
positively controlling liquid dispensing from a commercially available 
liquid cartridge 28, with reduced downtime during replacement of spent 
cartridges 28. 
While a preferred embodiment of the invention has been shown and described, 
it is to be understood that modifications may be made to the preferred 
embodiment without departing from the scope of the invention. Accordingly, 
applicant wishes to be bound only by the claims appended hereto: