US 2442047 A
Description (OCR text may contain errors)
May 25, 1948. R` 1 KEMPER 2,442,047
ANTIDRIP POURING SPOUT Filed Sept.' 25, 1944 INVENTOR zoeszv J. Kar/:m12
f ATTORNEY Patented May 25, 1948 UNiTED sTATss Para @FFME ANTIDRIP POURING SPOUT Robert J. Kemper, San Carlos, Calif.
Application September 25, 1944, Serial No. 555,63?
- upon close scrutiny.
The invention possesses other advantageous features, some of which with the foregoing will be set forth at length in the following description where that form of the invention which has been selected for illustration in the drawings accompanying and forming a part of the present specification is outlined in full. In said drawings, one form of the invention is shown, but it Ais to be understood that it is not limited to such form, since the invention as set forth in the claims may be embodied in -a plurality of forms.
Referring to the drawings: Figure 1 is an elevation of a pitcher embodying the pouring spout of my invention, a portion of the pitcher being.
broken away to disclose the structure. Figure 2 is a fragment of the spout in vertical section, and on a larger scale than Figure 1. Figure 3 is a sectional view of the spout, the plane of section being indicated bythe line 3 3 of Figure 2.
Whenever a liquid is poured from a container. the problem presented by dripping of some portion of the liquid must be met. Although the economic element of waste may not be important in the direct loss of liquid, it can be a large element indirectly by reason of the effect of the lost portion. The handling of acids and other corrosive liquids in a laboratory presents lsuch a problem. Perhaps equally, or more important, is the largely esthetic problem presented by dripping edges in the handling of medicines, milk, syrups, and other liquids in the home and public eating places, in which of course there is also the indirect waste of labor and materials.
I have discovered that dripping from a pouring spout can be prevented with complete certainty and irrespective of the character of the liquid poured, whether a light benzine or a heavy molasses. Upon analysis, a surprisingly large and interrelated number of physical phenomena are found to be involved. It is believed however that surface tension and viscosity in the liquid. capillarity, molecular or mass attraction between the liquid and the spout, and gravitational pull are the chief phenomena involved.
The structure of my invention comprises a spout l on the container 2 and having a groove 3 for channeling the nal dribble of the pouring liquid. Across the groove at its end is a dem 4 having a. sharp crested edge i. The groove 8 concentrates the liquid 'at the end of the flow into a narrow stream or thread in which its surface tension and viscosity tend to exert their maximum restrictive influence. The groove also presents surfaces l between which and the liquid. an
attraction exists;` and this attraction whatever'7 its value 'is an added Iforce tending toward and contributing to the result sought.
The shape of the groove as shown in Figure 3. is not perhaps the ideal one if this molecular or mass attraction were the only consideration to be taken into account. Certain practical values and the operation of other phenomena also enter; and the resultant of these suggests a groove having a broadly triangular section with a rounded bottom 8, and of the general shape shown in Fig? ures 2 and 3.
The dam l is placed at the ldischarge end ot the groove, which is -best located centrally in the bottom surface of the spout, and which extends to the end of the spout, terminating against the inner face 9 of the dam.
Preferably the dam is shaped on this inner face to extend smoothly from the crest edge into the bottom of the groove, in order to give at least a small effect, to the momentum or the last portion of the poured liquid, so that such momentum. small as it may be, tends to carry the nai portion of liquid outwardly and .awayirom the discharge or outer face Il of the dam.
When pouring is completed, the container, which may bea pitcher of milk or a becker or bottle of acid, or any other vessel having a pouring lip or spout, is returned to its normal upright position, as suggested in Figure 1. During this return movement the bulk of the flowing liquid is of course cut oil! almost immediately by the mere action of gravity. However there will always be a small portion of -the liquid in the groove and between the sides of the spout. about to pass over the crest of the dam. Much of this will pass over, clearing the dani and falling free into the receiving receptacle. The remainder may be considered as composed of two portions. one on the inside of the dam which collects in the groove and runs down into the container; and the second portion which is small, and which for a fraction of a second. remains at the crest but on the outside of it. This portion corresponds to what ordinarily constitutes the dropwhich clingto and'rundown the outside o!I the container.
Itwlll benoted that the outer lace ii oi the dam. in the normally upright position oi the con tainer is undercut. sloping downwardly and backwardly-with reference to the body of the dam.
Because of the sharp crest edge of the dam and this undercut iront or discharge face; or more properly perhaps. 'because of the shape and po-` sition oi the Yentire dam, the second portion of liquid which lies momentarily against and on the outside of the crest oi the dam, is
mail in volume-appreciably smaller than is ordinarily formed from a vsmooth or rounded pouring lip.
' Because ofthe small mass of this second portion,- the forces of surface tension. molecular cohesion and capillarity are increased relative to the. gravitational' pull and other small iniluencesv tendin ',to cause'the second' portion to drip from thees'pout or run down the outside of it, with -the i result that it is pulled back over the dam and into thev groove, leaving the dam crest and its discharge tace completely free of liquid. This q yretraction or actual uphill ilow of the drop. ac-
cording to the position ot the receptacle at the instant it occurs. is readily observed; and always follows under the conditions I have described. irrespective ot the character of the liquid o r the rapidity with which the pouring is per'- formed.
While I have chosen an ordinary pitcher for illustration. it will be obvious that my invention i may be applied to the widest range of chemical and pharmaceutical laboratory ware. Medicine bottles especially afford a tremendous field; and
the application ot the invention to all manner of kitchen and table furnishings. as well as to contai ners for liquids in commercial packages will be A i the container proper may vary widely u insizeandvolumathepouringspoutlsusually small, and 'because oi the simple nature ot the structure ci my invention it may be incorporated into the spout structure with no complications in the manufacture thereof. Such a spout appears like any other; and it is only on close examinaticn that the small groove and dam are observed.
1. A pouring spout including a groove extending along the bottom of the spout in the direction oi' iluid pouring therefrom, and a dam hav# ing a sharp crest and an outer face undercut from the crest edge in the'normally upright position of the spout and disposed across the outer end of the groove.
REFERENCES CITED The following-references are of record in the ille of this patent: Y l
UNITED STATES PATENTS Number Name Date 1,236,955 Lindsay Aug. 14,1917 1,512,984 Willis Oct. 28, 1924 FOREIGN PATENTS Number Country Date 366,207 Great Britain Feb. 4, 1932 55,286 Germany Feb. 6, 1891 86,856 Germany Mar. 30, 1895 457,585 Germany Mar. 27, 19,28