DISPENSING BOTTLE AND METHOD
Field of the Invention
The present invention relates to a dispensing bottle having a drop forming plug, a sealing overcap, and a method for assembling the drop forming plug to the bottle. While the primary application is in the dispensing of accurate and reproduceable volumes for blood banking reagents, clinical chemistry assays and the like, it will be appreciated that because of the accuracy reproduceability and resealing features, the same unit can be used for packaging σyano- acrylate, epoxy-type glues, and other products requiring accurate measurements and a purging reclosure. The Prior Art
The prior art is generally summarized by FIGS. 1 and 2 of the accompanying drawings. The exemplary prior art squeeze bottles A have a drop forming plug B inserted at the neck portion. A central channel C is provided in the drop forming plug body, with a rounded plug bottom D. The plug bottom along with the neck of the bottle define a capillary crevice E adjacent to the interior portion of the bottle neck. In usage, a residue F can gather in the crevice E and cause contamination. Also because of the use of a single channel C, means are not provided to control the form of a drop. The prior art bottles A are normally provided with an overcap G, as shown, which threadedly engages the neck threads of the bottle, and does not provide for sealing and purging of the channel C interior of the drop forming plug B.
What is needed in a uniform drop forming bottle is a construction which will permit the formation of uniform size and weight droplets independent of the pressure applied. For example, it is highly desirable to know that with a given solution, exactly twenty drops will be exactly one illiliter. Furthermore it is desirable to have a plug which inhibits contamination. In addition, it is highly desirable to utilize an overcap which will assist in purging the channel C, or other open communication between the drop forming plug and the interior of the bottle. Thus when the ._
bottle is not in use, the tendency for clogging in the channel portion should be minimized.
Summary of the Invention
The present invention is directed to a squeeze bottle assembly including a drop forming plug and an overcap, as well as the method for assembling the drop forming plug to the bottle. The drop forming plug is formed with a drop forming cone at its upper portion, connected by means of a capillary tube to a drop forming reservoir interior of the neck of the drop forming plug. The drop forming plug is seated within the bottle with a construction eliminating any crevices that the heretofore rounded underportion of drop forming plugs have displayed. The overcap is provided with a purging pin and seal plug which centeringly engage the drop forming cone and capillary tube of the drop forming plug. The method of assembly contemplates positioning the drop forming plug on a plug arbor which orients the same. Thereafter a transfer seat is positioned over the drop forming plug and engages the plug. The transfer seat, while carrying the drop forming plug, is positioned over the bottle. The plug is centered by means of the transfer bead on the neck of the bottle. Thereafter the plug is seated into position snugly pressed into the bottle. Interlocking means are provided on the lower portion of the drop forming plug to sealingly retain the same within the neck of the bottle.
In view of the foregoing it is a principal object of the present invention to provide a bottle and drop forming plug in which the metering is precise as to the weight and volume of each drop, or multiples of such drops, and which is essentially independent of the pressure applied to the bottle so long as the drop forming function continues.
A further and important object of the present invention is to provide a drop forming bottle which is free of interior traps for any of the material contained by the bottle.
Yet another highly desirable object of the present invention is to provide a self-sealing overcap for the
bottle, which in addition to sealing, promotes purging of the capillary tube in the bottle.
Still another object of the present invention is to provide means, including the physical construction of the drop forming plug, to assemble the same to the bottle with positive orientation based upon the coordination between a plug arbor, a transfer seat, and the transfer ring on the bottle itself.
An objective achieved, relating to all of the above objectives, is the production of a uniform drop forming bottle which is resealable and self-purging, the inherent cost of which is not substantially in excess of existing containers.
Description of the Drawings
Further objects and advantages of the present invention will become apparent as the following description of an illustrative embodiment proceeds, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a typical cross-sectional view of an exemplary prior art drop dispensing bottle, and in which the reference characters are shown with arabic letters;
FIG. 2 is another example of the prior art type drop dispensing bottles, having a slightly modified config¬ uration from that shown in FIG. 1;
FIG. 3 is a partially diagrammatic view illustrating the bottle assembly illustrative of the present invention in its inverted position and diagrammatically disclosing drops being dispensed;
FIG. 4 is an exploded partially broken view of the three principle elements of the bottle assembly including the bottle, the drop forming plug, and the overcap;
FIGS. 5, 6 and 7 are in exploded relationship, much the same as shown in FIG. 4;
FIG. 5 is an enlarged sectional view of the upper portion of the bottle showing the finish and the transfer bead;
FIG. 6 is a transverse sectional view of the drop forming plug;
FIG. 7 is a transverse sectional view of the overca ;
FIG. 8 is a front elevational view of the plug arbor used in the assembly of the drop forming plug to the bottle;
FIG. 9 is a front elevation of the transfer seat used in conjunction with the plug arbor;
FIG. 10 is a partially broken view showing the drop forming plug in its seated relationship with the transfer arbor shaft;
FIG. 11 is a partially broken diagrammatic view illustrating how the transfer seat engages the drop forming plug from its position on the plug arbor for subsequent positioning within the bottle; and
FIG. 12 is a partially transverse sectional view of the transfer seat showing how the drop forming plug is inserted into the bottle neck, and centered by means of the bottle transfer bead coordinating with the centering ring of the transfer seat.
Description of the Preferred Embodiments The Prior Art
The prior art as pointed out above is shown in FIGS. 1 and 2, where the various elements common to both examples are identified by arabiσ numerals. These include a squeeze bottle A, a drop forming plug B, a central channel C in the drop forming plug, and a curved plug bottom D. The curved plug bottom D defines a capillary crevice E which can and normally does accumulate a residue F. This residue, not present with the balance of the ingredients housed in the bottle A can become contaminated, or otherwise degraded to a point where interference with the balance of the contents of the bottle A causes undesirable side effects. The overcaps G provided with both bottles are standard, and normally do not contact the upper portion of the bottle neck terminating at the upper end of the channel C.
The bottle assembly 10 illustrative of the present invention, particularly as shown in FIGS. 3 and 4, includes a bottle 11, the upper portion of which is closed by a drop
for ing plug 12. The bottle 11 is formed with a flexible body permitting it to be squeezed by the user to assist in expelling contained fluids by drop information. As shown in the exploded view in FIG. 4, an overcap 14 is threaded to the neck of the bottle, and completes the closure. Necessarily to dispense the contents of the bottle 11 in drop form, as shown in FIG. 3, the overcap 14 is first removed. Thereafter by squeezing the body portion of the bottle 11, the drops are dispensed into a reagent dish 15, or to any other receptacle or on any other surface as desired. To be noted in both
FIGS. 3 and 4, and described in greater detail below, the bottle is provided with a transfer bead 18. This transfer bead not only assists in anchoring a tamper-proof type sealer cover, but also assists in the method of assembling the drop forming plug 12 to the bottle 11.
Shown in essentially the same exploded form as FIG. 4, are FIGS. 5, 6 and 7. These are all transverse sectional views essentially on the same scale to illustrate how the bottle 11, drop forming plug 12, and overcap 14 interrelate to each other. Beginning with FIG. 5, it will be seen that the bottle 11 has a threaded finish 16 at its upper neck portion. The transfer bead 18 is provided in the neck portion of the bottle above the bottle reservoir portion, and extends diametrically outwardly from the diameter of the threaded finish 16. At the very upper portion of the bottle finish 16 provision is made for a seating ring 19 extending internally into the bottle neck, and in spaced vertical relationship to the seating ring 19, provision is made for a drop forming plug seat 20, here shown as an annular shoulder 20.
Turning now to FIG. 6, it will be seen that the drop forming plug 12, is provided with a drop forming cone 21 at its upper portion. The included angle of this cone is normally between 50° and 65°, depending upon the drop size and weight to be dispensed. Immediately below the drop forming cone 21, provision is made for a capillary tube 22 which is in open communication with the drop forming reservoir 24 of the drop forming plug 12, and interiorly of the
23 of the drop forming plug 12. The lower portion of the drop forming plug 12 has a seal ring 25 which is the maximum diameter of the drop forming plug 12, and also dimensioned and formed to seat within the finish 16 of the bottle 11. Provision is made flanking the seal ring 25 of the drop forming plug 12, including an upper seat 26 and a lower seat 28 which respectively engage the seating ring 19 and seat 20 of the finish 16 of the bottle 11. The contact between seat 28 and seat 20 provides a crevice-free interior interface of drop forming plug 12 with bottle 11.
Turning now to FIG. 7 showing in detail the overcap 14, it will be seen that the central interior member is a purging pin 30, proportioned and dimensioned to extend into the capillary tube 22 of the drop forming plug 12. A conical seal plug 31 is provided immediately above the purging pin 30, and opposing the seal plug 31 is an interior seal ring 32. The side walls 34 of the overcap 14 terminate at their lower portion with a serated skirt 29, interiorly of which threads 35 are provided to engage the threaded finish 16 of the bottle 11. It will be appreciated that as the overcap 14 is rotated by the serated skirt 29, the purging pin 30 along with the seal plug 31 engage in a pressure-type purging reaction on any reagent or other material contained in the drop forming plug 12, specifically in the drop forming cone 21 and the capillary tube 22.
The materials employed in forming the bottle 11, drop forming plug 12, and overcap 14 are essentially hydro- phobic and susceptible of easy molding. The material should also accommodate autoclaving. The bottles, for example, are formed of a primary K123 polypropylene with a clarifier modification. The plug and overcap are formed of Eastman Tenite polypropylene No. 4250.
While dimensions do not necessarily form a critical portion of the present invention, the nature of the interfit should be noted. For example, the diameter of the capillary tube 22 is approximately .030 inches. The depth of the capillary tube is .139 inches, and the distance from the top of the capillary tube 22 to the upper portion of the
forming cone 21 is .060 inches. An included cone angle of 64° is formed in a typical acceptable embodiment, with the interior diameter of the top forming cone 21 being .105 inches, and the outer portion at the upper portion of the neck 23 is .185 inches. All other dimensions, and most desirably that of the sealing ring 25, and the interior of the bottle neck finish 16, are for a pressure-type interfit. Also to be noted is the diameter of .025 inches of the purging pin 30 of the overcap 14, and a 50° included angle of the conical seal plug 31. The relationship between the overcap 14, drop forming plug 12, and bottle 11 is such that the lower edge of the serated skirt 29 of the overcap 14 is in a spaced relationship with the transfer bead 18, when the overcap 14 is securely threaded to the bottle 11.
In forming the exact size of the droplets, no precise mathematical formula is now known. The same is determined emperically subject to a few guide lines. For example, the changing of the diameter and/or length of the capillary tube 22 affects the speed at which the drop is formed (assuming the same or constant pressure on the flexible bottle 11). In all cases a gentle squeeze or touch is required. It is the included angle of cone 21 that really changes the drop size. The drop size is increased by in¬ creasing the wetted surface area which relates to the in¬ cluded angle of the cone 21.
The method of assembling is illustrated in FIGS. 8-12. The first element is a plug arbor 40 having an arbor shaft 41 terminating at its upper portion with a plug seat 42. A gage block 44 is provided at the base of the shaft 41, and atop the base 45 of the plug arbor 40. The plug seat 42 is dimensioned to firmly receive the interior portion of the drop forming plug 12 interior of the seal ring 25. This is the configuration shown in FIG. 10. Thereafter the transfer seat 50 is positioned over the top of the plug arbor 40, and it engages the neck of the drop forming plug 12, as shown in FIG. 11.
More specifically, as shown in FIG. 12, the transfer seat 50 is provided at its upper portion with a neck
to engage the drop forming plug 12. A plug shoulder 52 is provided at a lower portion to engage the drop forming plug 12 and press the same into the finish 16 of the bottle 11. A centering ring 54 is provided interiorly of the transfer seat, and first engages the transfer bead 18 of the bottle 11, prior to the drop forming plug being pressed into position within the finish 16 of the bottle 11. Thus the transfer bead 18 of the bottle 11 not only provides a seat for a shrink band, but in addition is an important adjunct to the assembly of the bottle with the drop forming plug 12.
Various modifications of the precise dimensions and configuration of the subject bottle assembly 10 are contemplated. The usages can vary as well, and need not be restricted to chemical, biological, pharmaceutical, or medical goods and reagents. The same will perform its function of precisely metering droplets independent of the pressure applied to the bottle for color additives, glue, and the like. The method of assembly illustrated in FIGS. 8-12 are primarily directed to the ultimate product component handling and assembly jig. It is contemplated, for example, that the drop forming plugs may be oriented through a vibratory feeder, and then the same are placed onto a plurality of plug arbors. Thereafter similarly a single or several transfer seats 50 are employed to receive the drop forming plugs, and then transfer the same for positioning on the bottle 11 as shown essentially in FIG. 12.
Although particular embodiments of the invention have been shown and described in full here, there is no intention to thereby limit the invention to the details of such embodiments. On the contrary, the intention is to cover all modifications, alternatives, embodiments, usages and equivalents of the dispensing bottle, as fall within the spirit and scope of the present invention, specification, and appended claims.