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Publication numberUS2330149 A
Publication typeGrant
Publication dateSep 21, 1943
Filing dateFeb 16, 1942
Priority dateFeb 16, 1942
Publication numberUS 2330149 A, US 2330149A, US-A-2330149, US2330149 A, US2330149A
InventorsLouis W Schaaff
Original AssigneeWaldes Kohinoor Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 2330149 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Patented Sept. 21, y 1943 y 33ans DROPPER Lodis w. schaart, Jacks() to Waldes Koh-I-No n Heights, N.,Y., assignor or, Inc., Long Island City,

N. Y.. a corporation of New York y l ,Application'rebruary 1s, 1942, serial No. 431,169 7 Claims. (Cl. 221148) 'I'his invention relates to improvements in droppers of the type commonly referred to as medicine droppers,` although it will be understood that droppers in ,accordance with the present invention are capable of generalusage in measuring and dispensing liquids other than medicines. j

Droppers as usually constructed employ an open-ended glass tube formed with a restriction at one end and carrying a rubber bulb at the other which is manipulated to both ll the dropper and to expel the liquid therefrom in the form of drops. While this form of dropper has enjoyed 'wide usage, it is nevertheless open Ato objection, notably the difficulty in cleaning, Athe requirement that a nice kdegree of pressure be exerted on the-bulb in dispensing drops therefrom, and the deleterious effect that'bothtime and chemicals have on the frubber bulb `used therewith. Moreover, shcrtagesin'essential raw materials such as rubber` give `indication that rubber. bulbs for droppers will not be readily available, and make apparent the necessity of developing a substitute for the rubber bulb or of providing a functionally effective dropper which does away entirely with the `rubber bulb.

The present invention contemplates and' has for its principal objects the provision of a novel and improved dropper which" is effectivein operation, which is soconstructed `that the requirement of a rubber bulb for` operating: the

same is dispensed with entirely, and which instead may be manufactured complete from readily available materials; theprovision of a dropi per which accurately forms and measures each drop regardless of the force or pressure applied in manipulation; the provision of a dropper which may be readily taken apart and cleaned; and the provision ofV a dropper which is of rugged and substantially non-breakable construction,

which can be inexpensively fabricated and as` sembled in quantity, and which is unaffected by age and the' chemicals with which it is used.

Other objects will be in` part1 obvious and'in part hereinafter pointed out in connection with the following analysis of this invention wherein is illustrated an embodiment of the `invention in detail.

In the drawings lig.y 1 vis a :front elevation of dropper of the present'invention;

Fig. 2 is a rear elevation .of the dropper illustrated in Fig. l; 1

l'ig; 3 is a section along line 3--3 of Fig. 1;

Fig. 4 isa section along lined- 4 of Fig. 1.

the improved Y In .the drawing, wherein like characters `designate like parts throughout the several views, the improved dropper is shown as constituted by two elongated half-sections `lll and i2 which are hingedly related by ahinge pin I4, of which the section Ylll will be referred toas the front section and the section l2 as the rear section. Each section is provided with a dat, outwardly convexed handle or grip portion, the grip` portion |2a of the under section terminating in a for-r wardly extending tongue lZb of depth corre-v sponding to thethickness of the end of the upper grip portiony lila ot the front section. The upper terminal edge lob of the frontsection is normally spaced slightly from the under lacel ofthe tongue, but when iinger pressure is exerted .on the ygrip-portions the handle portion lila elongates slightly whereupon its top` edge engages against the tongue which thereupon acts as a stop and limits the degreev of finger pressure which can be exerted. v

' Somewhat below its grip portion the rear section is provided with forwardly extending hinge ears I2C spaced to receive a mating ear Ille formed on thefront section and extendingrearwardly thereof. The hinge pin I4 projects through said ears and thus hingedly connects the, sections.

Below the `hinge ear each section is formed with anelongated semi-cylindrical portion, the' elongated portion 52d of the rear` section opposing the like portion Mld of the front section. Thus the elongated portions lild, |2d complement eachother to provide an elongated tubular reservoir of, small diameter for the liquid to be dispensed which will hereinafter be termed the reservoir portion.' f i The lower endl of each semi-cylindrical portionv connects with a semi-spherical portion of radius substantially greater than the radius of the semicylindrical portions.'1 Like thelatter portions, the semi-,spherical Yportions designatedV ille and l2e are oppositely'disposed as shown and thus cornextending discharge spout ltend at an angle of approximately 45 to the VVerbe stamped or die-formed from one of the available metals, preferably a metal of a springyv or. exible nature, the metal finish of which may be retained; or the metal sections may, either prior to or after assembly, thereupon baked or heat-treated. In either case the selected material should be such that the sections are flexible to the extent that when assembled and linger` pressure is applied to one or both of the handle grip portions thereof, the spout and valve end of the sections have relative separating movement as indicated in dotted lines in Fig. 3 and that release of such finger pressure causes the sections to close in automatic manner. To add to the flexibility of the grip por tions of the device the same are preferably provided With punched openings, of which the opening lilh. of the front section may diameter than the opening |2h. of the rear section. This difference in dimensioning of the openings is also useful in enabling the user to distinguish between the front and rear of the dropper.

In use, the dropper is immersed in the liquid and, being open at its upper end, the liquid rises to the level of the liquid in the container from which it is taken. When withdrawn from the container the liquid is held by capillary attraction in the reservoir and dropper regulating portions of the device. To measure and dispense a drop, slight nger pressure is exerted on the handle portion thereof, causing the spout and valve ends of the sections to open sufficiently that the pressure of the column of the liquid in the reservoir portion causes enough liquid as will form a drop to escape under the valve and to flow down to the extreme end of the spout portion.` Release of finger pressure on the grip portion causes the valve to again seat in the spout portion, thus to cut off the drop from the liquid column, whereupon the sci-formed drop falls from the end of the spout portion'under its own weight. Repeat operations as aforesaid may be carried on, each resulting in the formation and dispensing of a drop, until the liquid column is exhausted.

In the aforesaid operation, the spherical drop regulating port-ion constituted by the spherical half sections Ie, |2e serves not only in holding by capillary action a portion of the liquid column, but, by rea-son of its relatively great volume which is substantially larger than that of a drop of liquid, permits the drop to form and release itself from the liquid column when the equilibrium between the capillary holding action and the pressure of the liquid column is disturbed as by opening the valve lg. Upon release of a drop from the liquideontained in the spherical portion, a very small quantity of the liquid remains therein, but upon closing the valve the liquid column lowersinto the spherical portion the amount of the released drop.

which `is moldable i be enamelled and be of smaller reason of the is provided.

By suitable calibration, the reservoir portion of the dropper can be preformed to hold a predetermined volume of liquid corresponding to a certain number of drops thereof. By molding the sections from one of the suggested plastic materials, extreme accuracy of liquid volume is obtained. To indicate the capacity of the reservoir in terms of drops contained therein, suitable markings indicated in Fig. 1 may beapplied to the outer surface of one or both sections, preferably the front section IIJ. By fabricating the section from transparent plastic, the quantity of liquid held in the liquid column can be determined visually by reference to such markings.

Manipulation of the dropper as aforesaid results in the formation of drops which are equal in size and volume, account being taken of the viscosity of the liquid being dispensed and its specific gravity. It will also be self-evident that a dropper in accordance with the present invention provides greater uniformity of drop and greater accuracy as to the amount of liquid dispensed than droppers operated by a rubber bulb filled with air because in the latter case the size of the drop and the number of drops is a function of the pressure exerted on the bulb. With a dropper of the present invention, the drop forms irrespective of the degree of pressure exerted by the user, there being no provision for increasing this pressure or for accelerating the formation of the drops as by increased pressure.

From the foregoing analysis of the invention, it will be seenthat a functionally effective dropper eliminating the requirement of a rubber bulb Such a dropper may readily be taken apart and cleaned, is unbreakable, and, in view of its simplicity of construction, lends itself admirably to economic, accurate production.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limit- 1 ing sense.

I claim:

1. A' liquid dropper of the class described comprising two elongated half-sections cooperatively related to form a small diameter, generally tubular reservoir adapted to hold by capillary attraction a column of the liquid to be dispensed, a handle portion at one'end of the reservoir, normally closed discharge means at the other end of the reservoir, and means whereby pressure ex.- erted on the handle portion effects operation of said discharge means'to release and discharge a .single drop of the liquid contained in the reservoir.

2. A liquid dropper of the class described comprising two elongated half-sections cooperatively related to form a small diameter, generally tubular reservoir adapted to hold by capillary attraction a column of the liquid to be dispensed, a handle portion at one end of the reservoir, normally closed discharge means at the other end of the reservoir, said discharge means including a discharge spout on one section and a valve on the other section normally cutting off communication between said reservoir and the spout, and

fmeans whereby pressure exerted on the handle portion effects movement of the valve to open communication between the reservoir and the spout.

3. A liquid dropper of the class described comprising two elongated halt-sections and means hingedly securing the sections,4 said sections being shaped to provide a liquid reservoir including an elongated, small diameter tubular portion andr to the lower end thereof, a hollow spherical dropforming portion, a handle portion extending above the tubular portion, and a normally closed discharge means extending below the spherical ly from its vsemi-spherical portion and normally closing oi communication between the semispherical portionv and the spout ofthe other section,v and means pivoting said sections together adapted to hold by `capillary attraction a column of liquid to be dispensed, a handle portion at one end of the reservoir, normally closed discharge portion, the said discharge means including a i discharge spout on one section and a valve on the other section, normally cutting off communication between the spherical portion and the spout, and means whereby pressure exerted on the handle portion eiTects movement of the valve to open communication between the spherical portion and the spout.

5. A liquid dropper of the class described comprising two elongated half-sections, each including a handle portion, an elongated semi-cylindrical portion, a semi-spherical portion into which the lower end of the semi-cylindrical portion opens, one section having a downwardly eX- tending discharge spout into which its semispherical portion opens, the other section having a tongue-like valve portion extending downwardwhereby said semi-cylindrical and semi-spherical,

portions complement each other to form a liquid reservoir and whereby pressure appliedto the handle portions operates to eiect communication between the spherical portion and the spout. 6. A liquid dropper of the class described comprising two elongated half-sections which together form a small diameter tubular reservoir means at the other end of the reservoir, means whereby pressure exerted on the-handle portion' eiiects operationV of said discharge means to release and discharge a single drop of lthe liquid contained in the reservoir, one of said sections carrying indicia representative of the dropcapacity of the reservoir. i

7. A liquid dropper of the class described comprising two elongated half sections which to.- gether forma tube of small diameter adapted to hold by capillary' attraction a column of the liquid to be dispensed, said sections being provided at theirfone ends withl connecting and operating means and at their opposite ends with portions complementing each other to form a normally closed discharge nozzle communicating with said tube.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5505712 *Apr 13, 1994Apr 9, 1996Mcmillian; Ray M.Medicament applicator with spatulate tip
US5582328 *Aug 18, 1994Dec 10, 1996Brown; Saundria L.Container for toiletries, personal hygiene products and articles
US7182915 *Nov 27, 2002Feb 27, 2007Bristol-Myers Squibb CompanyPipette configurations and arrays thereof for measuring cellular electrical properties
US7401971 *Mar 27, 2001Jul 22, 2008Arkray, Inc.Method for stirring liquid
U.S. Classification222/158, 222/517, 422/930, 222/215, 222/162, 222/420
International ClassificationB01L3/02
Cooperative ClassificationB01L3/0272, B01L2400/0481
European ClassificationB01L3/02D12