US3421664A - Pressurized dispensing container and method of filling same - Google Patents

Description

Jan. 14, 1969 H. z. SOKOL 1,

PRESSURI'ZED DISPENSING CONTAINER AND METHOD OF FILLING SAME Filed May 9, 1967 Sheet of 2 i I i vanuinpgilunrnrriluwlll HERBERT Z. SOKOL BY 1 q ATTORNEY 5.

Jan. 14, 1969 H. z. SCKOL 3,421,664

PRESSURIZED DISPENSING CONTAINER AND METHOD OF FILLING SAME Filed May 9, 1967 Sheet 2 of 2 STEP I. STEP 2. STEP 3. A202 STEP 4.

ATTORNEY 5.

INVENIOR United States Patent 3,421,664 PRESSURIZED DISPENSING CONTAINER AND METHOD OF FILLING SAME Herbert Z. Sokol, Atlanta, Ga.; Joseph Eichberg, executor of the estate of said Herbert Z. Sokol, deceased, assignor to GK Industries, Inc., Atlanta, Ga., a corporation of Georgia Continuation-impart of applications Ser. No. 502,656, Oct. 22, 1965, and Ser. No. 540,795, Apr. 6, 1966. This application May 9, 1967, Ser. No. 637,115 US. Cl. 222-340 1 Claim Int. Cl. G01f 11/04 ABSTRACT OF THE DISCLOSURE A dispensing container comprising a tubular side wall slidably receiving a piston having a deep skirt for stabilizing the piston and for nesting therewithin the compressed spring which seats between the bottom of the container and the piston. The piston also includes an extension which projects through the bottom when the piston skirt is seated thereon, to aid in holding the piston during filling.

This application is a continuation-in-part of Ser. No. 502,656, filed Oct. 22, 1965 now abandoned, which in turn is a continuation-in-part of Ser. No. 540,795 filed Apr. 6, 1966 now abandoned.

Background of invention It has previously been proposed to provide dispensing containers comprising a spring disposed in one chamber of a container and separated from a second chamber by a piston device. A typical example of such prior proposals is that shown in the Kaye et al., Patent No. 2,809,774. In such prior devices, the spring acts as a supplement to a gaseous charge and material expulsion is a function of a differential in the hydrostatic pressure existing between the chambers on either sides of the piston. Such prior devices have the disadvantage of difficulty of filling, and, in addition, retain the necessity for the imposition of a gaseous charge to at least one of the chambers thereof.

Summary of invention To overcome the foregoing deficiencies, and to supply an improved container which is readily filled by either of two alternative filling methods by reason of its construction and which completely eliminates the need for the imposition of a gaseous charge, the present invention provides an improved container structure which is characterized by the lack of necessity for any pressurization of the container other than that occasioned during and incidental to filling the container with material to be dispensed.

The present invention relates essentially to a pressurized, piston-type container for fluid substances which employs a spring and piston arrangement in combination with a valve assembly in the controlled expulsion of the fluid materials from the container subsequent to filling. It is a basic objective of the invention to provide a dispensing container of the type aforesaid wherein charging of the container with gaseous materials, rendering the container dangerous under some circumstances, is overcome by replacement of the gas operated expulsion system with a piston-spring arrangement.

Patented Jan. 14, 1969 General objectives of the invention include the improvement of the efficiency of filling of container for fluid substances: reduction in the cost of pressurized packaging: minimization of the time of filling and material loss occasioned in filling: and provision of dispensing containers for materials of such viscosity as to be un suited to packaging with presently available aerosol containers.

Brief description of drawings Other and further objects and advantages of the invention will become apparent to those skilled in the art from a consideration of the following specification when read in conjunction with the annexed drawings, in which:

FIGURE 1 is a disassembled perspective view partially broken away for disclosure of details, of a container structure fabricated in accordance with the teachings of this invention;

FIGURE 2 is an enlarged, assembled view in vertical cross section of the container shown in FIGURE 1;

FIGURE 3 is a sectional view showing the piston bottomed within the container and illustrating one means for retaining the piston in such position against the action of the compressed spring;

FIGURE 4 is a diagrammatic view showing a sequence of filling operations employing a first method hereof; and

FIGURE 5 is a diagrammatic view showing a secondavailable filling procedure.

Detailed description Proceeding to a description of the invention in more detail, and referring initially to the container per se as shown in FIGURES 1 and 2, it will therein be observed that the invention structure is generally identified by reference numeral 10. The pressurized container 10 comprises an elongate tubular, generally cylindrical body portion 12 having an inner wall 14 and top and bottom sections 16, 18, respectively. The body portion 12 may be formed of any suitable mate-rial such as metal, plastic, coated paper, or the like, and if desired, the inner wall 14 may be coated with an anti-adherent metal foil or synthetic resinous substances such as that sold under the trademark Teflon. A top structure 20 is connected to the body portion 12 at its upper end 16 and has an outer rim portion 22 crimped about the end 16. As shown in FIG- URE 2, the top structure 20 terminates in an upper bead 24 and has a ridged side wall 26 intermediate the crimp and the bead. The wall 26 is domed as shown in order to provide for more complete dispensing of materials from the container as appears below.

Seated in and fixed to the head 24 is an inwardly cupped Valve seat 28 with a central opening 30 formed therein. A valve assembly 32 including an enlarged stem 36 frictionally gripped in a boss 38 of the cup element 28. The member 34 further includes an upper stern section 40 projecting through the opening 30. A cap assembly 42 including a rim 44 frictionally seated about the bead 24 and cup member 28 has a top plate 46 of integral formation separated from the main rim portion by a slot 48 which extends about a major portion of the periphery thereof and is connected to the rim only at a relatively small section 50 whereby the plate 46 is depressible with respect to the cap structure. A spout 52 is connected to the wall 46 and to a handle element 54 and communicates through an opening 56 with a passageway 58 of an interior stem element 60. The stem element 60 is frictionally engaged with the upstanding stem 40 of the valve, and the structure of the valve is such that, upon inward movement of the handle 54 which effects inward or sidewise displacement of the valve stem 40, material under pressure within the container is permitted to pass through the valve and passageway 58 and out of the spout 52.

As is well known in the art, a frictionally engageable cover 62 with an opening tab 64 thereon may be connected in overlying relation about the cap 42 to prevent inadvertent dispensing of material and to protect the cap and spout structure when not in use.

The invention structure further comprises a base member 66 of inwardly concave form and having a peripheral crimp section 68 connected about the end 18 of the container body portion. It is an important feature of the invention that the base member 66 have a central opening 69 formed therein, the purpose of which appears in more detail hereinafter. This opening may be of the relative diameter shown in FIGURES 1 and 2 or may be larger where one alternative filling procedure is employed, as is explained below.

A critical component of the present invention comprises a special piston structure 70 formed of metal, plastic, Teflon coated metal, or some similar low friction substance. The piston 70 comprises an annular skirt 72 presenting a generally vertical inner wall surface 74 and an outer wall surface 76. The head or crown of the piston is surrounded by an annular extension 80 of the skirt 72, the inner surface of such extension being outwardly inclined in knife edge fashion to terminate in the sharp edge 82. The outer surface of this extension is coplanar with the outer surface 76 of the piston skirt.

The crown of the piston comprises an upwardly and inwardly inclined annular wall 84 jointed at the annular apex 88 to the downwardly and inwardly inclined wall 86. An elongate, hollow stem 90 is formed as a continuation of the wall 86, a substantially solid fiat portion 94 extends between the lower edges of the wall 86 and closes the upper end of opening 92 in the stem 90.

A coil spring 98 having a base end 100 tapering to the reduced diameter top end 102 is used to effect material expulsion. Preferably, but not necessarily, the upper end 102 of the spring engages an annular pusher member 104 which is received in the annular recess provided by the apex portion 88 of the piston while the base end 100 is dimensioned to seat upon the base cap 66 in spaced relation to the inner surface of the container side wall. The pusher member 104 has a downturned inner flange 106 that is surrounded by the spring end 102 and serves to center the spring relative to the piston. The member 104 offsets any angularity of the upper convolution of the spring and also relieves any stress on a thin walled piston.

The piston and its arrangement with the spring is such that the piston remains centered with respect to the inner wall of the container at all times. The fully compressed length of the spring is less than the length of the piston skirt. Thus, the lower end of the piston skirt seats upon the base 66 before the spring can become fully compressed (see FIG. 3). This action, taken in conjunction with the fact that the upper end of the spring seats within a recess substantially smaller in diameter than the diameter of the piston skirt allows the piston to be selfaligning or self-centering. Consequently, integrity of the piston-to-container contact is always maintained, minimizing leakage. The spring is preferably nonuniformly wound so as to possess a non-linear spring constant so that a more uniform expulsion force per unit of volume expelled is achieved.

Referring to the illustrated methods of filling the containers hereof as disclosed in FIGURES 4 and 5, in the sequence of operations disclosed in FIGURE 4, the stem 90 can be omitted from the piston 70 and said piston is initially positioned adjacent the base portion 18 of a container to which the top portion has been applied but not the dispensing valve assembly. Material is then introduced into the container as indicated by the arrow in the second sequential step, followed by capping of the container by seating of the valve structure in step 3. In step 4, the thus assembled container is moved to a position wherein its base portion 18 is gripped by a conventional sealing means 200 over a spring insertion plunger housing 202. There, the spring 98 is forced upwardly by a plunger 204 compressing the spring and forcing the piston into the container to its preselected limit of dwell. The means 200 thereafter serves to seam or crimp the base portion 66 in its desired position.

In FIGURE 5, step '1 shows a substantially reversed procedure wherein the base element 66 is connected to the container subsequent introduction in step 2 of the piston 70. Following this, pressure means such as pneumatic pressure on a pressure operated plunger means 300 is employed to compress the spring, seating the piston skirt on the base 66 and extending the stem through the opening 69. Thereafter, in step 4, while material M is placed within the container the stem 90 is gripp d, as by clamps 250, until the capping procedure and placement of the valve has been completed whereupon the stem may be cut or otherwise released.

In either of the above methods, it is necessary that the steps of spring compression, filling, and capping employ the interaction of the elongate sleeve of the piston and its depending stem. It will be observed that these procedures are carried through without pressurization at any time of the container, and that all filling procedures take place at ambient pressure. This permits filling of the containers with materials of high viscosity and avoids danger to the operators.

In the procedure illustrated in FIG. 5, the hollow stem 90 may be secured beyond the container bottom 66 by means other than clamps 250. For example, as shown in FIG. 3, a plug 108 may be inserted in the stem to grip the stem between the plug and the rim of the bottom 66 surrounding the opening 69. To facilitate insertion of the plug 108, the end of the stem 90 may be provided with axially extending slits 110. Preferably, the plug will be of a size to fit within the dish or hollow of the bottom 66 so that the rim of the bottom can rest on a flat surface. Thus, the plug 108 can be left in place during transport of the container so that the material in the container will not be subject to pressure, which might induce some leakage, until the device is to be used.

Having described and illustrated the invention in some detail and having shown and described several embodiments thereof, it will be understood that these descriptions and illustrations have been offered only by way of example, and that the invention is to be limited in scope only by the appended claim.

What is claimed is:

1. In a container having an interior wall, a top, a valve assembly in the top, and a base, the container having a substance to be dispensed therein:

a piston shaped for sliding movement Within the container;

the piston including a head portion with a depending stem of given length; and a peripheral skirt depending from said head, the skirt including an outwardly tapered upper extension and the skirt being in frictional contact with the interior wall to divide the container into an upper chamber for the substance and a lower force applying chamber;

a spring seated on the base and biasing the piston toward the valve;

the base having an air relief opening formed therein,

said air relief opening and said stem being vertically aligned;

said air relief opening being of a size of admit passage of the lower end of said stem therethrough during filling,

said lower end of said stem being hollow, and

a plug inserted in the hollow end of said stem externally 5 6 of said base and holding said piston with said spring 2,809,774 10/ 1957 Kaye et a1. 222387 X und compression, 3,338,478 8/1967 Hedblad 222387 X References Cited ROBERT B. REEVES, Primary Examiner.

UNITED STATES PATENTS 5 N. L. STACK, JR., Assistant Examiner.

551,540 12/1895 Fowler 222387 1,303,845 5/1919 Blair 222 -34O US. Cl. X.R. 1,971,450 8/ 1934 Heitmuller et a1 222340

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