Cartridge For Storing, Mixing And Dispensing A Plurality Of Ingredients

Abstract

A cartridge for storing separately a plurality of ingredients, at least one of them in a separate frangible envelope within the cartridge, and then for mixing the ingredients and expelling the mixture, includes a cylindrical container apertured at each end, a piston, a piston rod slidably passing through one end of the container and through the piston and having a substantially fluid tight seal with the piston and with the side walls of the container, a mixing element affixed to the rod on the side of the piston remote from that one end of the container, and means to couple the piston to the piston rod to permit drive of the piston lengthwise of the container by the piston rod after rupture of the envelope and mixture of the ingredients by the mixing element.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a cartridge for storing, mixing and dispensing multiple component compositions wherein at least one component must be kept separate from the others until just prior to use of the mixed compositions.

2. Description of the Prior Art

In many industrial applications, multiple reactive materials are used wherein each reactive material must be kept separate during storage to prevent premature reaction between the reactive materials. When they are to be used, the reactive materials are intimately mixed together and the mixture is then used within a short period after mixing. In the past, it has been necessary to provide separate storage containers for the reactive materials and then to mix them together in the proper proportions. This operation is undesirable from several standpoints. In the first place, many such mixtures require rather critical proportions of each component and must therefore be carefully measured or weighed out. Furthermore, the components of such mixtures are often viscous liquids, and it is not easy to dispense, measure and mix such materials.

Attempts have been made in the past to integrate the operations of storing, mixing and dispensing two or more ingredients in a single device. However, such devices are subject to one or more disadvantages which this invention effectively overcomes.

U. S. Pat. Nos. 3,164,303 and 3,195,778 are two disclosures of such devices which are known to us. In each of these a diaphragm or piston divides the interior of a cylinder into two storage chambers, one in front and one behind the diaphragm, and a mixing element in front of the diaphragm is affixed to a handle which passes through the diaphragm and out through the rear wall of the cylinder. When the two ingredients in the two storage chambers are to be mixed, an opening is formed in the diaphragm, by rupturing it in U.S. Pat. No. 3,195,778 and in U.S. Pat. No. 3,164,303 by unscrewing the mixing element from a central aperture in the diaphragm otherwise closed by the mixing element. The diaphragm is then pulled to the rear with the handle so that the ingredient behind the diaphragm passes through it to the frong thereof where the two ingredients can be mixed together by further manipulation of the mixing element. The contents of the cylinder can then be expelled through an opening in the front wall of the cylinder, either by re-engaging the mixing element with the diaphragm to form an imperforate piston (in U.S. Pat. No. 3,164,303) or by operation of an auxiliary piston disposed at the rear of the cylinder in U.S. Pat. No. 3,195,778.

In either case provision is made for only two ingredients and, moreover, if the two storage compartments are to be each one-half the length of the cylinder and if the entire contents of the cylinder are to be expelled for use, then in the storage condition of the device the handle must extend out past the rear wall of the cylinder, a distance equal to one-half the length of the cylinder. A similar device is disclosed in U. S. Pat. No. 3,140,078.

SUMMARY OF THE INVENTION

In contrast, this invention provides a cartridge comprising a container having a substantially cylindrical side wall and an apertured end wall at each end thereof, a piston slidable within and lengthwise of the container, a piston rod slidably passing through the piston and through the aperture in one of the end walls, the piston having a substantially fluid-tight seal with the piston rod and with the side walls of the container, a mixing element affixed to the piston rod on the side of said piston remote from that one end wall, and two-part interengaging means of which one part is arranged on said piston and of which the other part is arranged on said piston rod.

The cartridge of this invention can be used to store two, and even a greater number of ingredients. Moreover, when the cartridge is in the storage condition, the piston rod is disposed within the container for substantially its entire length hereby resulting in a device of greater compactness than heretofore attained.

While the invention is widely applicable, it is particularly useful for mixing and dispensing flexible polyurethane foam systems wherein a polyether or polyester must be mixed with an isocyanate or polyisocyanate at the point of use and the mixture used almost immediately. For example, in the fitting of a ski boot, it is of great importance that the boot conforms substantially with the contours of the wearer's foot. In order to obtain this precise fit, ski boots are fitted with an orifice at the heel portion through which a polyurethane foam reaction mixture is forcibly injected while the boot is being worn by the purchaser. The polyurethane foam subsequently formed fills the cavity surrounding at least the wearer's foot and upon curing of the foam, there results a permanently shaped boot interior custom fit to the wearer's foot. The ski boot cavity filled by the foam generally includes the complete cavity with the exception of that associated with the wearer's toes. The entire cavity can be filled if desired. This invention provides a simple, effective and economical method for deploying a polyurethane foam system in ski boots and other footwear and in other similarly inaccessible places where an in situ, exactly molded plastic or elastomer is required.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further described in terms of a presently preferred exemplary embodiment and by reference to the accompanying drawings in which:

FIG. 1 is a view of the cartridge of FIG. 2 as employed to inject a polyurethane foam reaction mixture through an aperture located in the heel portion of a ski boot;

FIG. 2 is an axial section through one form of cartridge in accordance with the invention, in the storage condition thereof;

FIG. 3 is an axial section of the cartridge of FIG. 1, shown injecting the foam reaction mixture through the aperture located in the heel portion of the ski boot; and

FIGS. 4, 5 and 6 are sectional views taken on the lines 4--4, 5--5 and 6--6 of FIG. 2 and in the directions identified by the arrows shown with those section lines.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 2 of the drawings, the cartridge of the invention includes a container generally indicated at 10. The container is formed with a cylindrical side wall 13 and end walls 11 and 12. While the container is shown as being of circular cross-section, this is not necessary; it may be a cylindrical container of any other convenient cross-section.

The container may be employed for storing one ingredient, or indeed for storing two or more ingredients if they are mutually non-reactive, while the remaining reactive ingredient or ingredients are stored in one or more envelopes 25. The cylindrical container 10 and the other parts of the cartridge of FIG. 2 presently to be described may be made of any suitable material, such as glass, plastic or metal, or a combination of such materials.

The end wall 12 may be formed integrally with the side wall; the end wall 11 is threadedly or otherwise affixed over the side wall 13. The end wall 11 includes a nozzle 14 extending therefrom and defining a central aperture 15 which can be closed by means of a cap 16. The end wall 12 similarly includes a central aperture 17 formed in an axial extension 18 of that end wall, this extension being of hexagonal or other non-circular section.

A piston rod 19 slidably passes through the aperture 17 in the end wall 12 and has a handle 20 affixed at the outer end thereof. The piston rod 19 slidably passes through the central hub portion 28 of a piston 21 and has affixed to the inner end thereof a mixing element 22. The mixing element may have one or more apertures 23 therein (FIG. 5) to facilitate its mixing function, and it may be provided with points or spikes, as indicated at 24, to facilitate rupture of envelopes, as shown at 25, for containing separate reactive ingredients before the cartridge is to be used.

The piston rod 19 may, but need not, possess a fluid-tight fit with the end wall 12 at the aperture 17 therethrough.

The piston 21 desirably has a fluid-tight fit with the cylindrical side wall 13, e.g. of the same quality as is provided in a pump or syringe. Two-part interengaging means are provided with one part on the piston rod 19 and with the other part on the piston 21, by means of which the piston and piston rod can be detachably coupled one to the other. In the embodiment illustrated, these interengaging means comprise a female thread 26 on piston 21 and a male thread 27 on piston rod 19 at the inner end thereof directly behind the mixing element 22.

The mixing element 22 is seen in end elevation in FIG. 5. It may have, as shown, an outer diameter somewhat smaller than the inner diameter of cylindrical side wall 13. The spikes 24 and apertures 23 are clearly shown in FIG. 5.

The piston 21 is similarly illustrated in the sectional elevational view of FIG. 4. It possesses at its outer limit a close fit with the side wall 13. The piston includes a central hub portion 28 which has a sliding fit with the piston rod 19, except when the threads 26 and 27 are engaged with each other.

FIG. 6 shows the engagement of the hub 28 on the piston 20 with the axial extension 18 of the end wall 12. On the side of the piston 21 remote from the mixing element 22, the hub 28 has an angular section 29 as indicated in FIG. 6, fitting within the angular section extension 18 of the end wall 12. In the loaded cartridge as provided ready for use, one, or more than one, ingredient (if mutually non-reactive) is loosely contained in the cylinder 13 between the piston 21 and the end wall 11. One or more additional ingredients are contained in suitable amounts in rupturable envelopes 25.

When the ingredients within the cartridge are to be mixed, the handle 20 is pulled to the left, as seen in FIG. 2, drawing the mixing element 22 with it. The envelope or envelopes 25 are compressed between the mixing element 22 and the stationary piston 21 and are ruptured. Reciprocation of the handle 20 drives the mixing element 22 back and forth within the cylindrical container 10 and thereby effects mixing of the ingredients. When the mixture is to be expelled, the piston rod 19 is again drawn to the left and rotated to engage the threads 26 and 27, the piston 20 being held against rotation by the engagement of its angular section 29 with the extension 18 of the end wall 12. The piston 20 may now be driven to the right as shown in FIG. 3 to expel the contents of the container out through the aperture 15 in the nozzle 14. FIG. 3 illustrates the cartridge in the process of injecting the foam reaction mixture into a ski boot. Nozzle 14 is threadedly engaged with adaptor 30 which is inserted into the orifice 31 of a ski boot. After the contents of container 10 have been discharged, the cartridge is disengaged from adaptor 30, adaptor 30 is withdrawn from the orifice 31 and orifice 31 is then plugged.

Optionally, when the cartridge is in the storage condition, nozzle 14 may be sealed by a pellicle 32 and when the cartridge is to be employed for discharging the contents stored therein, pellicle 32 may be pierced by suitable means such as the spike 33 disposed within the barrel of the adaptor 30.

Although we have described preferred illustrative embodiments of this invention in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the construction details may be modified or changed without departing from the spirit or scope of the invention.

Claims

We claim:

1. A cartridge comprising:

a. a container having a substantially cylindrical side wall and an apertured end wall at each end thereof;

b. a piston slidable within and lengthwise of the container;

c. a piston rod slidably passing through said piston and through the aperture in one of said end walls, said piston having a substantially fluid-tight seal with said piston rod and with the side walls of the container;

d. a mixing element affixed to said piston rod on the side of said piston remote from said one end wall; and,

e. two-part interengaging means of which one part is arranged on said piston and of which the other part is arranged on said piston rod.

2. The cartridge of claim 1 wherein the mixing element is a disc of smaller diameter than the internal diameter of the container, said disc possessing one or more apertures for the free passage of ingredients therethrough.

3. The cartridge of claim 2 wherein the mixing element possesses one or more spikes on the side thereof facing the piston for facilitating rupture of a frangible envelope stored in the container.

4. The cartridge of claim 1 wherein said one end wall of the container possesses an axial extension of non-circular section and the side of the piston remote from the mixing element possesses an axial extension of non-circular section substantially fitting within the axial extension of said one end wall.

5. The cartridge of claim 1 wherein the two part interengaging means comprises a female thread on the piston and a male thread on the piston rod at the inner end thereof directly behind the mixing element.

6. The cartridge of claim 1 wherein the end wall remote from the end wall through which the piston rod passes possesses a nozzle fitted over the aperture of said end wall.

7. The cartridge of claim 1 wherein the end of the piston rod exterior to the cartridge chamber has a handle (24) affixed thereto.

8. The cartridge of claim 1 constructed of plastic.

9. A cartridge comprising:

a. a container having a substantially cylindrical side wall and an apertured end wall at each end thereof;

b. a piston slidable within and lengthwise of the container;

c. a piston rod slidably passing through said piston and through the aperture in one of the said end walls, said piston having a substantially fluid-tight seal with said piston rod and with the side walls of the container;

d. a mixing element affixed to said piston rod on the side of said piston remote from said one end wall;

e. two-part interengaging means of which one part is arranged on said piston and of which the other part is arranged on said piston rod; and

f. at least one frangible envelope within the container between said piston and mixing element.

10. A cartridge comprising:

a. a container having a substantially cylindrical side wall and an apertured end wall at each end thereof;

b. a piston slidable within and lengthwise of the container;

c. a piston rod slidably passing through said piston and through the aperture in one of said end walls, said piston having a substantially fluid-tight seal with said piston rod and with the said side walls of the container;

d. a mixing element affixed to said piston rod on the side of said piston rod remote from said one end wall;

e. two-part interengaging means of which one part is a female thread on the piston and a male thread on the piston rod at the inner end thereof directly behind the mixing element; and

g. means for substantially preventing rotation of the piston during disengagement of the piston rod therefrom.