CN1130300C - Unit dose dispense package - Google Patents

Abstract

A unit dose storage and dispenser cartridge (10) for a unit dose of an ingredient (12) includes a storage and dispense container dispensably containing a unit dose of the ingredient (12). The container (10) includes a cylindrical interior wall (18) defining a cartridge passageway (30) having an ingredient-containing ingredient storage cavity portion (36). The container (10) further defines a dispense opening (24) communicating with the ingredient storage cavity portion (36) and includes a first sealing member (70) removably sealing the dispense opening (24). A dispense piston (34) is movable by a dasher rod (15) through the ingredient storage cavity portion (36) so as to dispense the unit dose of the ingredient (12) through the dispense opening (24). An openable vent (86) is positioned in registry with the cartridge passageway.

Description

unit dose dispensing device

The present invention relates to the field of dispensing containers. More specifically, the present invention is directed to unit dose dispensing containers for activating catalysts for thermally curable impregnants.

The present invention relates to a unit dose cartridge container for ingredients to be mixed with a given amount of mixing components. A typical use of the present invention is as a storage and dispensing cartridge for azobisisobutyronitrile (vazo) catalyst. The azobisisobutyronitrile catalyst is usually dispensed into a 5 gallon heat cure impregnant jar, which is filled to 4 gallons. The combined mixture is then used to seal porous metal or plastic parts.

Typically the catalyst is added to the impregnating agent in the production facility where the mixture is added. The current method for mixing the catalyst with the impregnant involves scooping by hand a quantity of azobisisobutyronitrile paste from a wide mouthed liter container. Once the azobisisobutyronitrile has been added to the 5 gallon jar, the jar is sealed and shaken until the azobisisobutyronitrile is mixed with the impregnant.

However, one liter container of azobisisobutyronitrile catalyst contains about one kilogram of azobisisobutyronitrile catalyst to catalyze about 7.6 altars of heat-cured impregnant. Since the heat cure impregnant jar generally has a smaller opening than the AZBN container, a certain amount of AZBISN needs to be scooped and scraped off to complete its transfer. Also, the measuring tools used by each operator may be different so that this method of mixing cannot accurately dispense the desired amount of catalyst to a jar of impregnant. As a result, the catalytic rate per jar of mixture may vary from operator to operator. This variation resulting from the imprecise partitioning of azobisisobutyronitrile thus prevents precise quality control of the mixture used.

These known methods for distributing the azobisisobutyronitrile catalyst also pose hazards to personnel and the environment. For example, hand scooping of azobisisobutyronitrile can expose operators to the irritating azobisisobutyronitrile paste itself. And, because the liter container cannot provide azobisisobutyronitrile for an even number of altars, and because the scooping method cannot guarantee the accurate measurement of the amount of azobisisobutyronitrile scooped, it is likely to be found in the discarded liter container will still contain a certain amount of azobisisobutyronitrile, and they may accumulate when excavated and landfilled in the future.

It is known in the art that the azobisisobutyronitrile catalyst can be mixed with the impregnant prior to shipment, but the mixture must then be shipped refrigerated to preserve its life. The added expense of refrigerated shipping the mixture makes this method prohibitively expensive since the two ingredients may need to be shipped to various plants remote from the component's manufacturing site.

Accordingly, it would be desirable to provide a transport and dispensing cartridge for an azobisisobutyronitrile catalyst that reduces or eliminates hazards to personnel and the environment, and provides a high degree of assurance of accurate dispensing of the catalyst into a jar of heat-cured impregnant.

The present invention provides a unit dose storage and dispensing cartridge for a unit dose formulation comprising a storage and dispense container dispensably containing the unit dose formulation. The container includes a cylindrical inner wall defining a barrel channel having an ingredient storage chamber portion containing the ingredient. The container further defines a dispensing opening in partial communication with the ingredient storage chamber and includes a first sealing member for removably sealing the dispensing opening. A dispensing piston is movable by a push rod passing through the ingredient reservoir portion to dispense a unit dose of the ingredient through the dispensing opening. Place an openable vent in line with the barrel channel. It is contemplated to provide one push rod for each cartridge, or only one push rod for a certain number of cartridges. It is also contemplated that the present invention may be provided in kit form.

The present invention will be more readily understood when reading the "Detailed Description of the Invention" with reference to the following drawings.

Figure 1 shows an exploded view of the unit dose cartridge assembly and plunger of the present invention.

Figure 2 shows a longitudinal sectional view of the unit dose cartridge assembly of the present invention.

Figure 3 shows an exploded view of the unit dose cartridge assembly of Figure 2 .

Figure 4 shows a longitudinal sectional view of the piston used in the unit dose cartridge assembly of the present invention.

Detailed Description of the Invention

Referring to Figures 1-3, the present invention provides a cartridge assembly 10 for containing and dispensing precise unit dose ingredients. Assembly 10 is particularly useful for containing and dispensing azobisisobutyronitrile catalyst 12 into a jar of thermally cured impregnant (not shown). Although the present invention has been described as being useful for storing and containing unit doses of azobisisobutyronitrile catalyst 12, it should be understood that the present invention can be used for storing and dispensing any formulation. Except as noted below, the components of assembly 10 are preferably formed of suitable plastic materials. Assembly 10 includes a cartridge 14 for containing precise unit doses of catalyst 12 . An example of an azobisisobutyronitrile catalyst that may be contained and dispensed by the cartridge assembly 10 is sold by the assignee of the present invention under the trade designation "RESINOL(R) INITIATOR PASTE". A class of thermally curable impregnants particularly suitable for mixing with azobisisobutyronitrile catalyst 12 is currently sold by the assignee of the present invention under the trade designation "90C STOCK SOLUTION".

Cartridge assembly 10 includes an elongated tubular cartridge housing 14 . Cartridge 14 includes an elongated cylindrical wall 16 having an inner surface 18 and an outer surface 20 . Cylindrical tube 16 includes a distal open end 22 defining a dispensing opening 24 and a proximal open end 26 defining a mechanical inlet or plunger insertion opening 28 . The cylindrical wall 16 defines an elongated barrel interior 30 in fluid communication with the dispensing port 24 and the plunger insertion port 28 . The outer surface 20 of the cylindrical wall 16 forms thereon an annular flange 32 in edge-flush relationship with the second end 26 . It is also conceivable to stick a label 33 with a visible marking on the outer surface 20 of the cylindrical wall 16 .

A long, rigid push rod 15 may be provided as an integral part of the cartridge assembly 10, or alternatively, one push rod 15 may be provided per shipping unit of multiple cartridge assemblies. The push rod 15 is preferably made of a suitable plastic material and includes a first tapered end 15a for insertion into the cartridge housing 14 and a second end 15b from which an operator can manually actuate the first end 15a. The second end 15b preferably terminates in a disc-shaped putter head 17 . The length of the push rod 15 is preferably selected as described below. It is contemplated that the function of the push rod 15 may be performed by any item of the nature described, including a screwdriver, but this is by way of illustration and not limitation.

Assembly 10 further includes a piston 34 which is inserted into barrel interior 30 of barrel housing 14 to provide sliding frictional engagement with inner surface 18 of cylindrical wall 16 . Once the piston 34 is inserted into the cartridge housing 14, it further divides the cartridge interior 30 into an ingredient storage chamber portion 36 extending between the piston 34 and the dispensing port 24 and a portion extending between the push rod insertion port 28 and the piston 34. Push rod receiving portion 38 . Cartridge housing 14 contains azobisisobutyronitrile catalyst 12 and dispenses azobisisobutyronitrile catalyst 12 from ingredient reservoir portion 36 .

With additional reference to FIG. 4 , the piston 34 includes an elongated cylindrical piston wall 40 having a distal end 42 and a proximal end 44 . The cylindrical piston wall 40 includes an outer piston wall surface 46 , an inner piston wall surface 47 , and defines a piston interior 48 . The inner piston wall surface 47 preferably has a plurality of annular stiffening ribs 49 formed thereon to increase the structural rigidity of the cylindrical piston wall 40 . The outer piston wall surface 46 is machined to form a sliding frictional engagement with the inner surface 18 of the cylindrical wall 16 .

A domed end wall 50 of the piston extends from the distal end 42 to form a convex surface 52 that projects into the ingredient storage chamber portion 36 of the assembly 10 . The convex surface 52 terminates at a central transverse plane 54 . The end wall 50 also defines a concave surface 56 facing the piston interior 48 and the pushrod receiving portion 38 of the housing 14 . The concave surface 56 is bounded circumferentially by an axially central plane 58 opposite the plane 54 . A pushrod engaging hub 60 extends from plane 58 toward piston interior 48 and includes a cylindrical hub wall 62 defining a pushrod receiving chamber 64 . The hub 60 receives the distal end 15a of the push rod 15 in a frictional or abutting engagement.

Piston 34 preferably includes an annular flared scraper rib 66 extending distally from distal end 42 of cylindrical piston wall 40 . An annular groove 68 is defined between the convex surface 52 and the scraping rib 66 . The wiper ribs 66 are configured to form a wiper engagement with the inner surface 18 of the cylindrical wall 16 as the piston 34 pushes the azobisisobutyronitrile catalyst 12 through the ingredient reservoir portion 36 toward the dispensing end 22 . The scraping ribs 66 thereby reduce the amount of residual azobisisobutyronitrile catalyst 12 remaining in the cartridge housing 14 after dispensing.

Referring again to Figures 1-3, both the dispensing opening 24 and the plunger insertion opening 28 of the cartridge housing 14 are sealed for shipping and storage purposes. Cartridge 14 preferably forms a sealed container for azobisisobutyronitrile catalyst 12 . A dispensing seal 70 is removably secured over the dispensing opening 24 . Dispensing seal 70 is preferably formed from a metal foil such as aluminum or tin foil. Dispensing seal 70 may be glued to cartridge housing 14 or simply held in place by a dispensing end cap 72 . Although dispensing seal 70 is formed to be substantially circular, it is preferably provided with a graspable tab 71 extending radially outwardly therefrom. Tab 71 assists the operator in tearing dispensing seal 70 off cartridge housing 14 prior to dispensing the azobisisobutyronitrile catalyst 12 . A dispensing end cap 72 is secured to the dispensing seal 70 in frictional engagement with the dispensing end 24 . The dispensing end cap 72 includes a substantially flat circular base 74 circumferentially bounded by an upstanding shell engaging wall 76 . The shell-engaging wall 76 may include an annular shell-engaging rib 78 disposed on the rounded bottom 74 to enhance the flexible frictional engagement of the shell-engaging wall 76 with the cartridge shell 14 .

Since the cartridge assembly 10 may be exposed to high temperatures during its storage and transport, a vented seal 80 is provided to relieve any residual pressure buildup within the cartridge interior 30 . A vented seal 80 is removably secured to the tube proximal end 26 to cover the push rod insertion port 28 . The vented seal 80 is preferably made of a metal foil such as aluminum or tin foil. The vented seal 80 is preferably glued to the cartridge housing 14 or simply held in place by the proximal cap 82 . Although the vented seal 80 is formed to be substantially circular, it is preferably provided with a graspable tab 81 extending radially outwardly therefrom. The flap 81 helps the operator tear off the vented sealing device 80 from the cartridge housing 14 .

The vented seal 80 includes a centrally located vent hole 84 positioned to align with the push rod receiving portion 38 of the barrel interior 30 . The vent hole 84 is capped from the cartridge interior 30 by a reduced pressure vent 86 . Vent 86 includes a vent plug 88 aligned with vent hole 84 . The vent plug 88 is bounded by a first thin plate member 90 and a second thin plate member 91 in the circumferential direction and concentrically interposed therebetween. The first veneer layer 90 is glued to the seal 80 which is vented. Vent plug 88 is preferably made of microporous polytetrafluoroethylene. Vent 86 is of the type known in the art which prevents the exchange of air through vent 84 unless elevated temperatures cause residual pressure to build up in cartridge interior 30 at which point vent 86 will open and allow high pressure Air escapes through vent holes 84 .

Proximal end cap 82 is secured over vented seal 80 and annular rib 32 to form a frictional engagement with proximal end 26 of cartridge housing 14 . The proximal end cap 82 is a generally disc-shaped member including a flat circular base 92 defining a central bore 94 and bounded circumferentially by an upstanding shell-engaging wall 96 . The central bore 94 is machined to align with the vent hole 84 and allow the pushrod 15 to be inserted therethrough for engagement with the piston 34 . The central hole 94 is preferably so small as not to allow the push rod head 17 to pass therethrough so that the rounded bottom 92 prevents the push rod head from being pushed into the barrel interior 30 . The length of the push rod 15 will be preferred so that when the push rod head 17 leans against the proximal end cap 82, the piston 34 will not be pushed out from the barrel interior 30, and the convex surface 52 of the piston 34 will preferably be exposed through the dispensing port 24 .

Housing engaging wall 82 of end cap 82 may include an annular housing engaging rib 98 disposed on rounded bottom 92 to enhance the flexible frictional engagement of housing engaging wall 96 with cartridge housing 14 . Since the proximal end cap 82 must also flexibly engage the annular rib 32 protruding from the outer cylindrical wall 20, and the dispensing end cap 72 need only flexibly engage the outer cylindrical wall 20, the assembly 10 preferably requires The proximal end cap 82 has a larger sealing diameter than the dispensing end cap 72 . By providing end caps 72 and 82 with different seal diameters, assembly 10 is provided with an anti-misassembly feature which ensures that end caps 72 and 82 are placed over the proper ends 22 and 26 of tube 16, respectively.

Thus, the cartridge assembly 10 can be made to hold a precise unit dose of azobisisobutyronitrile catalyst 12, on the order of 130 grams, for mixing with a five gallon jar of heat-cured impregnant. The present invention minimizes operator exposure to the azobisisobutyronitrile catalyst 12 by providing a single-use disposable cartridge that minimizes operator handling of parts in contact with azobisisobutyronitrile. least. Furthermore, by providing and cleanly dispensing precise unit dosages of AZBIS catalyst 12, the present invention greatly reduces excess or unused AZBIS catalyst paste that may be discarded.

An operator may dispense azobisisobutyronitrile catalyst 12 from cartridge assembly 10 as described below. Push rod 15 may be inserted through central bore 94 of proximal end cap 82 to pierce vented seal 80 to extend through push rod receiving portion 38 and engage piston 34 . The tapered first end 15 a of the push rod 15 preferably projects partially into the push rod receiving chamber 64 and engages the hub wall 62 of the push rod engaging hub 60 . The operator can then remove the dispensing end cap 72 and tear the dispensing seal 70 from the distal end 22 of the cartridge housing 14 to expose the azobisisobutyronitrile catalyst 12 . The dispensing port 24 is then placed in line with or into the opening of the thermoset impregnant jar. Then, while maintaining the cartridge assembly 10 in the jar opening, the operator pushes the plunger head 17 of the plunger 15 to pressurize the piston distally toward the dispensing port 24 to inject the azobisisobutyronitrile catalyst 12 Distribute into jars. As the piston 34 moves toward the dispensing port 24 , the wiper rib 66 slides wiper along the cylindrical inner wall 18 to minimize residual catalyst 12 remaining in the cartridge interior 30 . The operator continues to push the piston 34 distally until the convex surface 50 protrudes completely from the barrel interior 30 . In this fully extended position, the cylindrical piston wall 40 is still in frictional engagement with the cylindrical inner wall 18 . Accordingly, the length of the push rod 15 is preferably selected to be sufficient to allow the convex surface 50 to protrude fully from the barrel interior 30, but not sufficient to push the piston 34 inadvertently outside of the barrel interior 30.

While the preferred embodiment of the present invention has been shown and described in detail above, it will be apparent to those of ordinary skill that various changes and modifications can be made without departing from the teachings of the invention. Accordingly, what has been set out in the foregoing description and accompanying drawings is offered by way of illustration only and not as limitation. The true scope of the invention is determined by the claims.

Claims (17)

1. Unit-dose storage and dispensing cartridges for dosing, comprising: An elongated tubular container having a first end defining a dispensing opening, a second end defining a plunger insertion opening, and an elongated passage extending between said dispensing opening and the inlet opening ; a first cap, which is removably and sealingly secured to said first end, aligned with said dispensing opening, wherein said first cap comprises a first metal cap secured to said first end of said container foil member; a second cover, which is removably and sealingly secured to said second end, aligned with said push rod insertion opening, wherein said second cover includes a first cap secured to said second end of said container Two metal foil members; a piston member slidably mounted in said channel, said piston having a first major surface and an opposing second major surface, said piston being placeable in said container to define a an ingredient reservoir portion positioned between said first major surface of said piston and said first end of said ingredient reservoir portion, said ingredient reservoir portion having a compartment for containing a unit dose of said ingredient volume; a push rod insertable through said push rod insertion port and engageable with said second major surface of said piston member to effect sliding movement of said piston member to dispense said a unit dose of said ingredient; and a pressure vent supported on one of said first and second metal foils for venting said ingredient storage chamber in said channel prior to insertion of said push rod through said push rod insertion opening The internal pressure generated in the part. 2. The cartridge of claim 1, wherein the ingredient is an azobisisobutyronitrile catalyst. 3. The cartridge of claim 1, wherein said first cap further comprises a first end cap secured to said first end. 4. The cartridge of claim 3, wherein said second cover further comprises a second end cap secured to said second end, said second end cap having a Covers with different sealing diameters. 5. The cartridge of claim 4, wherein said second end cap further defines a pushrod hole for passing said pushrod therethrough to engage said second end of said piston. The two major surfaces are joined. 6. The cartridge of claim 1, wherein said first major surface of said piston is arcuate. 7. The cartridge of claim 1, wherein said piston further includes a bendable annular edge for scraping engagement with said inner surface. 8. The cartridge of claim 1 wherein said second major surface of said piston defines a push rod receiving hub for engagement with said push rod. 9. A kit for storing and dispensing unit doses of ingredients into a volume of mixture comprising: an elongated hollow storage-dispensing cartridge for dispensably containing a unit dose of said ingredient in a sealed volume, said cartridge defining an elongated cartridge passage communicating between the dispensing end and the plunger insertion end; a piston adapted for scrape-sliding engagement with said barrel in said barrel passage, said unit dose of said ingredient being placeable between said dispensing opening and said piston; a pair of removable sealing members adapted for removable sealing engagement with said end, wherein said pair of removable sealing members further comprise a first metal foil adhered to said dispensing end and a second metal foil adhered to said push rod insertion end of said dispensing cartridge, wherein one of the first and second metal foils further supports an openable pressure vent; A push rod adapted to pass through said push rod insertion end for operation with said piston to dispense said unit dose of said ingredient therefrom in a single stroke. 10. A unit dose storage and dispense cartridge for a unit dose of ingredient comprising: A unit dose storage and dispensing container dispensably containing said ingredients, said container having a cylindrical inner wall defining a dispensing opening, a plunger insertion opening and a barrel passage having a an ingredient storage chamber portion containing ingredients, said container further comprising a first sealing member and a second sealing member, said first sealing member removably sealing said dispensing opening and comprising a first metal foil member, The second sealing member detachably seals the push rod insertion opening and includes a second metal foil member; a dispensing piston partially movable through said ingredient reservoir to dispense said unit dose of said ingredient through said dispensing port; and An openable vent is supported by said second foil member and positioned in alignment with said cartridge passage. 11. The cartridge of claim 10, wherein said first sealing member further comprises a first end cap secured over said first foil member. 12. The cartridge of claim 11, wherein the first foil member is adhered to the container. 13. The cartridge of claim 10, wherein said second sealing member further comprises a second end cap affixed to said second foil member, wherein said container is further on said container An annular protrusion is included adjacent the push rod insertion opening, thereby requiring that the first and second end caps be adapted to sealingly engage only one end of the container. 14. The cartridge of claim 13, wherein said second end cap further defines a push rod aperture for passing said push rod therethrough for engagement with said dispensing piston. 15. The cartridge of claim 10, wherein said dispensing piston includes an arcuate surface adjacent said ingredient and a flexible portion for scraping engagement with said inner wall of said container. circular edge. 16. The cartridge of claim 10, wherein the ingredient is an azobisisobutyronitrile catalyst to be dispensed into a heat curing impregnant container. 17. The cartridge of claim 10, further comprising a push rod releasably engageable with said dispensing piston through said push rod insertion opening for moving toward said The dispensing port pushes the piston to achieve dispensing of the ingredient.

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