US3431941A

US3431941A - Hermetically sealed container

Info

Publication number: US3431941A
Authority: US
Inventors: Valentine Hechler
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-04-25
Filing date: 1966-04-25
Publication date: 1969-03-11
Anticipated expiration: 1986-03-11

Description

March 11, 1969 v. HECHLER 1v 3,431,941

HERMETICALLY SEALED CONTAINER Filed April 25, 1966 v Sheet 1 3 j 50 84 WNW 56 L62 so INVENTOR.

VALENTINE HECHLERIZ' FIG. 3 BY HARB UGH AND THOMAS.

March 11, 1969 v. HECHLER |v HERMETI CALLY S EALED CONTAINER Filed April 25, 1966 Sheet 3 013 FIG. 2

FIG. 5

FIG. l0

+ 7- 3 Jr y s 3 INVENTOR.

VALENTINE HECHLER E HARBA UGH AND THOMAS.

United States Patent 3,431,941 HERMETICALLY SEALED CQNTAINER Valentine Hechler IV, 26 Meadow View Lane, Northfieid, lli. 60093 Continuation-impart of application Ser. No. 520,568, Jan. 14, 1966. This application Apr. 25, 1966, Ser. No. 545,007 US. Cl. 137--604 16 Claims Int. Cl. E03e 1/046; B05!) 7/30; B65d 35/08 ABSTRACT OF THE DISCLOSURE A variable capacity sealed container for storing and dispensing liquid under sub-atmospheric pressure in which a follower means externally exposed to atmospheric pressure moves easily in sealed relation to the container under liquid withdrawal by suction. The liquid is educted through a pressure differential responsive back flow check valve which under resting conditions closes, and supports the stored liquid and the follower means against movement in any orientation of the container.

Cross reference.-Applicants application Ser. No. 520,568, filed Jan. 14, 1966, of which this application is a continuation-in-part application.

This invention relates to a novel fluid mixing, storing and supply container and the method of forming and assembling its components.

The preferred embodiment is characterized by a blow molded unit having a tubular body portion with an integral closed end portion adapted to be severed therefrom preferably for slidable use in the tubular body portion to provide a contractible container, or, if not severed then as a mixture determining means in combination with the tubular body portion.

More particularly with the end portion severed from the body portion, the container assembly is characterized by having the end portion so constructed and arranged that it advances and retracts in sliding sealed relationship within said tubular body. Then when the container is being filled with liquid the two portions will expand to increase the enclosed volume, and when liquid is being withdrawn from the container assembly the two portions will contract towards each other to reduce the enclosed volume correspondingly.

In the disclosure to follow, it will be appreciated that the end wall of either portion can be provided with opening in which an eduction means may be mounted as hereinafter described but for purposes of description, the eduction means will be described as related to the end Wall of the tubular portion which is conformed to receive a closure means that is provided with an opening receiving the eduction means. The other portion is telescopically received in the tubular portion. Hereinafter the tubular portion will be referred to generally as the tubular wall member, the other portion inserted therein as the follower member, and the resulting assembly operating as a variable capacity sealed container will be referred to as the container.

An earlier form of this invention is shown in my copending application Ser. No. 520,568 where its use is associated with dispensing chemicals for horticultural purposes, the liquid being withdrawn from the container by suction. It is immaterial whether the suction is created by gravity flow syphon action, pump intake action or aspiration. It operates proficiently with a very slight negative gauge pressure, or differential, when connected for dispensing purposes and not only prevents unsafe differentials developing but provides a very enduring sealed relationship when not dispensing.

An object of this invention is to provide a fluid supply container having an open end like a bell jar with a removable retractible bottom-like follower member therein that preferably cooperates with a valved outlet and makes the dispensing of liquids therefrom economical, convenient and safe.

The present invention also relates to a multiple purpose container in which a solution or suspension can be mixed in exact proportions; the mixture can be stored without contact with air regardless of the quantity in the container and will not leak when stored; the mixture is free from inflow of any contaminating fluids and the container does not require a dip tube nor any priming for continuous or intermittent dispensing of liquid alone in any position.

A further characteristic of the invention is that the container is not critical with respect to any particular position or changing of positions it may assume and will dispense liquid under a very slight but desired differential of pressure across a spring closed back flow check valve, at any orientation or attitude in which it might be disposed, yet is equally secure against spilling, draining or leaking in use or in storage, whether connected to or disconnected from an idle flow-inducing device.

A further object of the invention is to provide a container in which mixtures can be made by shaking the container without any leaking, and, if dropped, will not break, spill or release any of its contents.

The invention is protected against contamination from any back flow of liquid to the container after it has left the confines of the container and against damage from excessive pressure differential.

A further object of the invention is to provide a container that will not easily rest on its eduction end and in all other positions, any solids that might be present in the mixture that might settle will gravitate away from the eduction opening.

Another purpose of the invention is to provide a container having a tubular member and a movable follower member whose relative production are quite closely maintained in that they are integrally formed simultaneously for identical shrinkage and cure and then when severed and assembled in production for relative movement between them, they provide exceptionally uniform devices.

A further object of the invention is to provide an inexpensive single molding method for a contractible volume plastic container which provides quick fabrication and assembly of container components.

The invention is further characterized by providing an improved liquid handling container for a large number of applications.

A further object of this invention is to provide a novel design of a fluid supply container and its method of molding, marking and cutting the parts thereof from plastic which are easily performed, and are economical and time saving.

These and other objects of this invention will be described or become apparent as the specification proceeds.

The invention is described in illustrative embodiments represented by the drawings in which:

FIG. 1 is a diagrammatic view of the device embodying this invention as used by way of example for horticultural purposes;

FIG. 2 is a side elevational view partly in cross-section of a fluid container of this invention as formed in a blow molding machine;

FIG. 3 is a partial side elevational view partly in crosssection of the bottom of the container as it comes from the blow molding machine, being cut to form the movable follower member;

FIG. 4 is a plan view showing two washer members as they are cut from one piece of flexible material such as neoprene for use as seals in this invention;

FIG. 5 is a partial view of the lower end of the bell jar portion of the container in cross-section showing the insertion of the movable follower member with its mounted seals or inserts into the open end of the tubular member left by the cutting operation of FIG. 3 after fabrication, cutting and assembly;

FIG. 6 is a fragmentary view in partial cross-section and partial plan view of the lower portion of the container with the movable follower member in place and a cover thereon;

FIG. 7 is a partial plan view in partial section showing the top cap and differential outlet valve and seal arrangement in the container of this invention;

FIG. 8 is a cross-sectional view taken along line 88 of FIG. 7;

FIG. 9 is a cross-sectional view of another top cap and outlet valve arrangement to be used as an alternative form of the invention; and

FIG. 10 is a cross-sectional view of a portion of FIG. 5 enlarged to show more clearly the clearances preferred between sliding elements and the edge contact of the seal with the elements engaged thereby.

Although this invention is described by way of example in connection with the horticultural aid for home owners who are unskilled in handling chemicals for application of solutions to plants for fertilizing and other benefits such as control of pests, it is not limited thereto and has many other uses in agriculture, parks laboratories and industry. The container of this invention can also be used where asceptic conditions are required and where it is desirable to withdraw liquid from the container by gravity or mild suction. Any tendency to create a substantial negative gauge pressure therein is obviated by movement of the follower member Within the bell jar-like tubular member. A feature of this invention is the provision of means to supply vapor-free liquids, mixtures and solutions at atmospheric pressure from vapor-free portable storage containers which can be carried, set down and disposed in any gravitational orientation or desired location.

Referring to FIG. 1 the container of this invention is illustrated at 10 as connected by means of a tube 12 to a mixing device 14 to supply a chemical for mixture therein with water that is supplied thereto through a hose 18 from a spigot 20 of a water supply system in a house 22. The mixture passes from the device 14 through hose 24 to a nozzle 26 equipped with a spray control 28. The spray 30 thus provided is accurately proportioned, uniform in concentration and easily applied. The mixing device 14 and the container 10 are portable and can be located next to the nozzle 26 or at the spigot. Moreover, the container can be secured directly to the mixing device to provide a unitary assembly if desired.

In FIG. 2, a preferred form of the container 10 embodying the invention is shown as made preferably of translucent or transparent polypropylene as it comes from a conventional blow molding operation.

The container comprises a bottle-shaped blank having a tubular wall portion 34 with a smooth inside wall surface 36 along a substantial portion of its length. The top wall 32 is formed with an outwardly crowned shape as at 38 for strength against inward collapse, a neck 40, an enlarged head portion having heavy screw threads 42 of the Mason jar type externally thereon and terminating in an axial flange 44 defining a substantially wide mouth opening 46. Externally the container 10 may be equipped with a handle (not shown) and volumetric indicia such as indicated at 48.

The lower portion of the tubular wall 34 of the blank 10 has an external circumferential reinforcement rib or bead for protecting its lower marginal edge snap supporting a protective cover. Below this head the blank has a truncated conical wall portion 54 inwardly tapering at an angle of 20 whose radii differential is approximately the same as its wall thickness whereby the external dimension at its lower end can provide a sliding fit within the inner wall 36 with a celarance of A to of an inch as shown in FIG. 10.

The lower marginal edge 52 of the bead 50 and the lower marginal edge or corner 56 of the wall portion 54 serve as guide lines for severing the bottom portion of the blank from the tubular portion by means of suitable cutters S2 and 84 as shown in FIG. 3 whereupon the head 50 then defines the bottom open edge of the container 10, and the severed bottom portion becomes the movable follower member indicated by the numeral 66 which comprises an integral unit having a cylindrical skirt 62, terminating in groove 70 having a depth diameter of 3" and a width of approximately defined by an upper wall 64 and a lower wall 66. A connecting wall 72 joins the lower wall 66 at a rather sharp corner 68 and diverges outwardly at an angle of l5-20 to another cylindrical wall 74 which defines therewith another corner 76. At the lower edge of the cylindrical wall 74 the follower member is enlarged to the same radial size at 78 as the skirt 62. Beyond this point the follower member terminates in a crowned wall or head 80 mating with the crown 38 to empty the container. The outside diameter of the wall 74 is approximately A; inch less than that of the walls '78 and '62 which provides a radial working clearance between the tubular wall 36 and the follower member wall 74 of approximately of an inch.

Then when the severed bottom portion is inverted and slipped into the open lower end of the tubular portion 34, as shown in FIG. 6, it functions easily as a follower member slidably engaging the surface 36 with the skirt 62 and the shoulder 78 spaced to prevent jamming of the follower member 60 both during assembly and in subsequent operation.

Referring to FIG. 4, two circular washer-shaped

elements

86 and 88 are shown, same being concentrically cut or stamped from a single fiat sheet of an elastomer such as Buna-N and having

outer edges

90 and 92 and

inner edges

94 and 96, respectively. Time, material and molding operations are saved by this concentric cutting of the

elements

86 and 88 by a cutter having three or four concentric cutting edges, the outer cutter making edge 90, the middle one or two

cutters making edges

94 and 92, and the inner cutter forming edge 96. The washer elements are made from stock approximately thick, the inside diameter of the larger element 86 being 2 /2" and the outside diameter 4". It will be observed that this thickness is about .010 less than the width of the groove (FIG. 10) and the inside diameter /z" less than the diameter of the groove 70.

As shown in FIGS. 5, 6 and 10 the fiat element 86 is converted to a seal by being stretched over the head 80 of the follower member 60 so that its inner edge 94 is received in groove 70 with the inner edge stretched by the groove to impose radially outward compression on the outer portion with its outer edge theoretically free to respond and flex in either direction. However, in view of the shorter depth of the wall 66, it Will flex around the

corners

68 and 76 and over

walls

72 and 74 and assume a cup shape. The corner 68 will lever the inner edge 94 against the wall 64 and the outer edge 90 will be levered by the corner 76 to diverge outwardly to form a sealing edge on the face of the washer that presses against wall 36 with a fine line contact at the edge of the seal and particularly after a lubricant coating has been applied to the exposed face of the seal, or incorporated in the seal material itself, capillary action between the seal and the wall 36 is in hibited. Then after the follower member has been inverted and pushed into the position shown in FIG. 6 in the open bottom with the seal edges 90 extending towards the top of the container, the container 10 is ready for use as an open top jar or bottle. Although frictional contact between the follower member and tubular member is desirably low in the embodiment, this can be varied by the type of seal and its size and thickness.

The

seals

86 and 88 preferably have a durometer of 70 and it will be observed with respect to seal 86 that al though it is under tension along its inner edge and related at its periphery to form a cup-shaped seal, the seal is so disposed that fluid pressure or weight in the container acts in a direction to increase the sealing pressure at both marginal edges thereof and thereby prevents capillary seepage or drip, particularly as safeguarded with a nonsoluble substance applied to the sealing areas. The seal tightens when the container is shaken, yet relieves excessive partial vacuum conditions if the follower member accidentally cannot move. Not only is the sealing effect complete, but when the time comes to refill the container and the plug 108 is removed, the follower member 60 will move downwardly under the weight of liquid supplied to the container more readily when the seal is so disposed.

It is to be observed that with the tubular portion 34 of the container fabricated of polypropylene or similar transparent or translucent plastic, the seal 86, particularly the upper edge 90 thereof can be used as an indicator to cooperate with indicia 48 to show the content of fluid in space 98 above it. By making seal 86 of a dark or colored material having a contrasting color, an accurate gauge is formed. Intermediate indicia between the 1 qt. and /2 pt. levels can be applied. Such indicia may be either raised or lowered letters and lines that are molded into the outside plastic surface when the container is molded.

In order to protect the working parts from dirt and the beaded edge .against damage as well as maintain the tubular configuration of the container and provide a flat surface upon which the container can be set, a cover 100 is provided as shown in FIG. 6 which engages bead 50 with a snap action by means of inner groove 102 in the manner described in United States Patent 2,487,400. Cover 100 also assists in locating and holding the follower member 60 in correct position when filling the container and also is protective during use or rough handling of the container whether the container is empty or full. Moreover, the snap cover 100 also prevents the accidental dislodgement of the follower member when the container 10 is open at the top and filled with liquid. Otherwise, it should be noted that with the container 10 filled with liquid and sealed or closed at the top there is still no freedom for the follower member 60 to become dislodged because air cannot displace the liquid even if the snap cover 100 were left off. The cover 100 has one or more air inlet holes as indicated at 103 so that a hermetic seal is prevented.

FIGS. 7 and 8 relate to the construction, attachment and operation of the closure 101 at the top of container 10. The closure includes a retaining ring .104 having an internally threaded flange 106 engaging threads 42 of neck 40. The ring holds a closure lid member 108 in place and the recess of the neck .at 40 below the ring 104 serves as a finger hold for lifting the container and to provide a sealing wall internally for the lid seal.

Referring more particularly to the lid member 108, it is a generally cup-shaped plastic molded part received within and having a radial flange 1 10 around its top edge clamped against the container flange 44 by the ring 104. The wall 112 of the lid follows the contour of the neck 40 in spaced relation to support a bottom wall 116 having a valve port opening centrally therethrough surrounded on the upper side by a valve seat .and a tubular element 114 defining a valve compartment. A radial groove 118 similar to the groove 70 is provided marginally in the bottom wall 112 to receive the inner edge 96 of the washer like member 88 with its outer unstretched peripheral edge 92 normally extending beyond the sides of the lid wall 112 to be deflected and received in sealing relationship between the wall 112 and neck 40 when the lid is inserted into the container opening in the same relation described heretofore for the washer element 86 (FIG. 10). The inner side of wall 114 has one or more longitudinal guide ribs 126. Four such guide ribs are shown.

In this connection the central portion of the follower means can serve as the bottom wall 116 .and be provided with a tubular element 114 having guide ribs 126 surrounding a valve set 124 at the valve port 122 to receive the suction outlet means which will now be described.

The guide ribs 126 in either instance extend inwardly from wall 114 to the outer edges of a resilient valve member which is held against valve seat 124 by means of a small metal disk 125 and a spring 132. The disk 125 is dimpled at 127 to embed in the valve member as urged by the spring while the other end of the spring is held in position by a flexible cap member 134 which fits snugly over wall 114 and into circumferential recess in bottom wall 116. The top end of spring 108 bottoms against the inner side of the cap 134. The cap has a central aperture 138 in its circumferential radially flanged top 136.

Fluid connection to the container is made by a tube inserted into the hole in cap 134. Preferably, the tube is terminated in a nipple .142 having a shank 144 with a passage therethrough and a circumferential flange 146 is provided to prevent over insertion, and with'a head 148 having a cross slot 152 in communication with the passage. The shank 144 of nipple 142 is press fitted into .a tube 12. The ring is not removed during connection of the tube. The head 148 is snapped through the aperture 138 where it is supported for appreciable resilient angular movement. The guides 126 provide spaces 156 (FIG. 8) for the passage of fluid around valve 130 in open position.

The arrangement shown in FIGS. 7 and 8 is assembled by dropping valve 130 into housing 114 between guides 126; the dimpled disk is dropped into place; spring 132 is placed thereon .and flexible cap member 134 is pressed into place. The seal 88 (FIG. 4) is stretched to fit into groove 118 and the assembly 101 is pressed into neck 40. With flange 110 in place, the seal is cupped between the inside of neck 40 and wall 120 of the lid 108. Ring 104 is then screwed onto threads 42 and this retains lid .108 in place. The entire assembly forms a valve-controlled outlet for container 10 which is responsive to a differential pressure as provided by the spring .132. During connection, head 148 of the nipple 142 is forced into aperture 138 of cap 134 so that the circumferential groove between flange 146 and head 148 are in sealed relationship with cup 134.

The complete assembly thus far described when connected to a source of suction becomes a supply source of hermetically sealed liquid. As the liquid is withdrawn through the nipple 142, the follower member 60 travels from the position shown in FIG. 6 toward the top of the container. The hole 103 in cover 100 allows air to enter behind the follower member 60 as it moves in container .10. The head 80 being crowned to conform with the shoulder 38 of neck 40, allows substantially all of the fluid contents to be withdrawn.

When a predetermined outflow pressure differential is present across the valve 130, the valve opens to allow fluid to pass through aperture 122, around the valve through spaces 156, into aperture 150 and into tube 12. Any shut-down of withdrawal or drop below the pressure differential allows valve 130 to close against any back flow, the valve being unidirectional i.e. open in one direction and closed in the other.

The device of this invention is adaptable to many uses, one of which is shown in FIG. 9 wherein a conventional aspirating sprayer 158 having a head 160 with a bleed hole 162 and threaded flange 164 is shown fitted to the top of container 10. Head 160 has the conventional Mason jar lid type of threads used in known spray apparatus.

the throat of a venturi 166 is connected to the cap 134 through tube 168 and thereby nullifies the need for orifice 162 generally required in a conventional spray apparatus to .allow air to enter. The advantage of this arrangement is that fluid communication and connection therebetween is established merely by screwing head 160 onto container 10, whereby tube 168 automatically becomes inserted into cap 134, the flexibility of tube 168 and cap 134 accommodating for any misalignment as the head .160 is screwed into place. There is no possible leakage through the bleed hole 162 which occurs with conventional equipment and if the suction outlet means is carried by the follower means the container can be set upside down on the flat top of a closure means having no opening therethrough.

All of the molded parts of the apparatus of this invention may be fabricated from any synthetic plastic material including, but not limited to, phenol-formaldehyde, phenol-fnrfural compounds with or without fillers, furan, urea formaldehyde, melamine formaldehyde, anilineformaldehyde, ethyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose nitrate, nylon, chlorinated rubber, isomerized rubber, vinyl acetate, vinyl chloride vinylidene chloride, vinyl butyral, vinyl alcohol, glyceryl phthalate, allyl resins, polyester resins, diallyl phthalate, polyacrylate esters, methyl methacrylate, polystyrene, modified styrene, acrylonitrile, polyethylene, polypropylene, polybutylene, polymonochlorotrifluoro compounds, polytetrafluoroethylene compounds, casein and shellac molding compounds. Preferably spring .132 is made of stainless spring steel. The choice of materials of construction depends upon the use to which the container of this invention is placed. Some of the plastics mentioned above may not be suitable for use with particular chemicals where others would.

From the foregoing description it is seen how the various objects stated are attained and how various and further advantages may be derived from containers embodying the invention. The container is hermetically sealed and can be used to store fluids indefinitely, yet is instantly ready for use. The container can be used in any position or left in any attitude during periods of non-use without leakage. The container also serves as .a mixing and measuring device in preparing solutions of treating agents and any unsoluble materials fall away from the outlet when the container is in use. Also, the follower 60 is easily removed from the empty container 10, for cleaning and rinsing.

The process of this invention comprises forming by blow molding, casting i.e. by centrifugal methods, the tubular open topped body portion with the cup-shaped follower member as an integral bottom part thereof. Thus, with the follower member having a continuous circumferential wall of predetermined outside diameter with respect to the inside diameter of the body portion and of the same general cross-sectional configuration, the two will have identical molding results and when severed and assembled they will provide a guiding or orienting arrangement with identical tolerances between the parts which assures closely held uniformity of production and performance. The process includes the step of forming the follower member in the shape disclosed herein and stamping or cutting the gaskets simultaneously to fit both the follower member and the differential valve housing with or without the use of indicia for the cutting step or steps.

The term fluid as used herein is intended to include discrete small size solid particles which are fiuidizable or flow like a liquid under the influence of a pressure, such as fluidizable catalyst particles used in the fluid catalytic cracking process of other such chemical processes. The container without the top differential valve can thus be used for the introduction of pre-measured quantities of a catalyst or reactant into a reactor without danger of contamination or spilling. The term suction action is intended to include any form of continuous or intermittent suction or withdrawal force such as a vacuum, a pressure differential, gravity flow or a syphoning action.

Having thus set forth the objects and described a preferred embodiment of the invention with its novel arrangement of parts and results attained, it will be seen how the stated objects are attained, particularly in the safe handling of horticultural chemicals by home owners, and how various modifications .and changes can be made therein without departing from the spirit of the invention.

\Vhat is claimed is:

1. A container externally subjected to atmospheric pressure for dispensing liquid therefrom in response to suction upon the liquid stored therein comprising:

(a) an intermediate tubular Wall member defining in part a container space for the storage of liquid;

(b) follower means closing one end of said tubular wall member in engagement therewith in sealing relationship preventing capillary seepage and readily movable in the downward direction under the action of the mass of the liquid therein upon the follower and in contact on one side with the liquid in the container space and exposed to atmospheric pressure on the other side;

(c) closure means closing the other end of said tubular wall member in hermetically sealed relationship;

(d) one of said means having a suction outlet means in communication with said container space and connectible in communication with a source of suction for educting stored liquid therethrough; and

(e) means carried by said suction outlet means including a differential pressure responsive check valve in said outlet means opening in the direction of eduction of liquid through said suction outlet means and biased to close to provide a negative pressure upon the liquid at said other end when said other end is the uppermost end of the container space at any given time for supporting the follower and the stored liquid in said container space against downward movement.

2. The combination called for in claim 1 in which said check valve, while oriented above the stored liquid, opens when the negative characteristic of the pressure on the outlet side of the check valve is increased to overcome the composite effect of the said negative pressure effective within the container and the bias to which the check valve is subjected.

3. The combination called for in claim 1 in which said biased check valve includes a spring element under a compression that urges said valve to close with an enduring sealing relationship against leakage under the weight of liquid in the container at any orientation to which the container is subjected when not dispensing.

4. The combination called for in claim 1 in which said follower means engages said tubular wall member with a readily slidable relationship and defining a circumferential recess, and

sealing means carried by said follower means in said recess held by the opposing pressures of the weight of the liquid above it and the amospheric pressure below it in sealing relationship with the wall member against capillary seepage of liquid under resting conditions and moved with said follower means for advancement along the intermediate tubular wall member by the differential between said opposing pressures.

5. The combination called for in claim 1 in which the intermediate tubular wall member defines a cylindrical inside surface and is of a formed synthetic plastic which will not break if dropped; and

said follower means being readily slidable in both directions in sealing contact with the cylindrical surface and movable downwardly under the weight of liquid filling the container space when said outlet means is removed.

6. The combination called for in claim 1 in which said closure means defines a predetermined internal contour at said one end of said tubular wall member and said follower means defines a contour adjacent said one end mating with said internal contour to evacuate substantially all of the stored liquid from the container space under suction upon terminal movement of the follower means during the eduction of stored liquid.

7. The combination called for in claim 1 in which said one of said means has a high point at said suction outlet means to evacuate said container of substantially all air through said outlet means ahead of stored liquid upon contractible movement of said follower means.

8. The combination called for in claim 1 in which said tubular wall member is made of a synthetic plastic material and is internally subjected to negative gauge pressure on said tubular wall member ahead of said follower means during movement of the follower means upon said eduction of liquid from the container space.

9. The combination called for in claim 1 wherein the follower means and said tubular wall member are blowmolded of translucent polypropylene.

10. A container in accordance with claim 1 in which said follower means comprises an axially disposed wall element having a circumferential recess, and tractible sealing means disposed within said recess in sealing engagement with the inside wall of said tubular wall member.

11. A container in accordance with claim 1 in which said follower means has a circumferential recess of lesser diameter than its tubular wall engaging surface and contiguous to a circumferential groove, a flat sided washershaped elastomer member in said groove having its inner edge portion distended and its outer portion under compression to flex its outer portion into said recess for the outwardly exposed side thereof to engage the tubular wall surface in sliding sealed relationship.

12. A container in accordance with claim in which said recess has an annular groove therein and said sealing means comprises a flexible fiat washer-like seal, the inner edge of which engages said groove and the outer edge of which is disposed between said recess and the inside wall of said tubular wall member, said outer edge being cupped toward said liquid confining space.

13. A container in accordance with claim 1 in which said outlet means has an inner depending circumferential shoulder, and said check valve is disposed within the closure member in said outlet means and has a circumferential wall adjacent and spaced from said shoulder, a central aperture in said closure member, a circumferential guide wall around said aperture, a cap member over said guide wall to define a valve compartment, an aperture in the top of said cap member, a nipple member press fitted through the aperture in the top of said cap member, and said carried means includes a valve seat around the aperture in the valve compartment, a valve member in said valve compartment registrable with said valve seat, means biasing said valve member against said valve seat, a circumferential groove in said closure member and a flexible washer-like seal in said groove, the inner edge of which engages said groove and the outer edge of which curls between the space between the shoulder of said outlet means and the shoulder of said closure member.

14. A container in accordance with claim 13 in which said guide wall has longitudinal spacing ribs in guiding relationship with said valve member and provides a fluid path therebetween, and said nipple member has a transverse groove communicating with said longitudinal aperture.

15. A container in accordance with claim 13 in which a tube is connected to said nipple member, a detachable cover member having an aperture therethrough engaging said outlet end of said container in spaced relationship from said valve, with said tube extending through said aperture.

16. In combination:

(a) a liquid dispensing device for mixing a liquid chemical with a liquid flowing under pressure;

(b) suction means driven by said liquid under pressure for supplying said liquid chemical to said liquid under pressure;

(c) a chemical supply container externally subjected to atmospheric pressure;

((1) an intermediate tubular wall member defining in part a container space for the storage of liquid;

(e) follower means closing one end of said tubular wall member in engagement therewith in sealing relationship readily movable in the downward direction under the action of the mass of the liquid therein and in contact on one side with the liquid in the container space and exposed to atmospheric pressure on the other side;

(f) closure means closing the other end of said tubular wall member in hermetically sealed relationship;

(g) one of said means having a suction outlet means in communication with said container space and connectible to said suction means for educting stored liquid therethrough; and

(h) means carried by said suction outlet means including a differential pressure responsive check valve in said outlet means opening in the direction of eduction of liquid through said suction outlet means and biased sufliciently to close with an enduring sealing relationship against leakage under the weight of liquid in the container at any orientation to which the container is subjected when not dispensing.

References Cited UNITED STATES PATENTS ALAN COHAN, Primary Examiner.

DENNIS H. LAMBERT, Assistant Examiner.

US. Cl. X.R.