US 2419795 A
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April 29, 1947. w, SAUNDERS 2,419,795
BREAST PUMP Filed July 11, 1945 INVENTOR. faul W 5 aunders 5 62 r ATTORNEYS Patented Apr. 29, 1947 UNITED STATES PATENT OFFICE BREAST PUMP Paul W. Saunders, Tarpon Springs, Fla.
Application July 11, 1945, Serial No. 604,415
This invention relates to breast pumps.
The general object of the invention is to provide a breast pump, including the breast applicator, milk receiving vessel and a suction pump, serially connected, constructed so as to be adapted for self use, and which when set aside maintains the suction pump in such position as to protect the moving parts of the suction pump from contact by liquid which may have entered the connection to the suction pump during use, or moisture condensing in said connection.
A more specific object of the invention resides in the novel construction of suction pump, particularly the means for protecting the valve parts from being contaminated by moisture or other liquid entering the pump.
Other objects of the invention will appear as the following description of a preferred and practical embodiment thereof proceeds.
In the drawing:
Figure l is a side elevation of the breast pump apparatus, the full lines showing the position of the suction pump assumed when the milk receiving vessel is supported upon a table, the broken lines representing a position of the suction pump when being used; and
Figure 2 is a longitudinal cross-section through the suction pump.
Referring now in detail to the drawing, the numeral I represents the breast applicator which is rigidly attached to the stopper 2 by means of the integral tubular outlet 3, which is tightly inserted in a hole in the stopper and opens at theinner end of the stopper.
The latter is tapered and fits frictionally into the mouth of the milk vessel 4. The latter is flat bottomed, affording a stable support for the apparatus, and is preferably of glass or other transparent material and provided with a scale 5. The taper of the stopper permits it to fit milk vessels having various sized months. The stopper has a short rigid tubular suction connection 6, fitted tightly in an aperture through the stopper, extending above the outer end of the stopper, and opening through its inner end.
The suction producing member or pump 1 comprises a tubular barrel 8, terminating in an exteriorly conical coupling flange 9. at its suction end, the taper of said flange being so slight as to constitute what is known as a sticking taper. The barrel 8 is provided with a cross partition It at the base of the flange 9, having an axial aperture I I for the passage of the stem [2 of the valve [3, the diameterof the stem being smaller than that of the aperture H, to permit air leakage. The valve l3 seats upon a washer 38, fitting within an annular rabbet 31 in the partition l0 surrounding the aperture II. The valve stem 12 extends beyond the partition I0 a suflicient distance to permit it to be surrounded by a spring 14, which abuts against the partition I0 and is confined by a collar l5 on the end of the valve stem. The valve opens inwardly against the tension of this spring.
The partition 10 is provided on both sides with longitudinally extending flanges l6 and I1 coaxial with the barrel 8, the flange l6 surrounding the valve I3, while the flange l1 surroundsthe spring l4 and collar IS. The internal diameters of the flanges l6 and Il are such as to provide air leakage past the parts which they surround.
The inner flange l6 provides, between itself and the barrel 8, a seating channel ill for the base of a plunger operating spring 20, housed within the barrel and being of such diameter for the greater part of its length that its coils are supported by the inner wall of said barrel.
The barrel has a screw cap closure 2|, at the end opposite the valve, through which cap the plunger rod 22 reciprocates, having a head or handle 23. The structure at the inner end of the plunger rod is conventional, the rod being reduced to form a shoulder retaining a washer 24, a cup leather 28, resting against the washer, and a back plate 25 resting against the cup leather. A nut 26 holds the assemblage on the rod.
The end of the spring 20 adjacent the plunger is of reduced diameter to seat against the back plate 25, surrounding the nut 26, by which itis centered. l
The inner face of the end of the cap 2| is provided with an exteriorly conical flange 21 coaxial with the barrel and projecting thereinto, of such diameter as to engage the margin of the cup leather 28 and re-expand it against the wall of the barrel 8 at the end of each plunger stroke. The cap has an air vent 29 and the barrelhas the fingerholes 30.
The flange I1 is spaced from the coupling flange 9 to form a channel 3|, having-a particular purpose, to be explained. 7. 7
The suction pump 1 is connected to the suction connection 6 of the stopper by a flexible tube.32-
having a coupling cup 33 at one end. Said cup hasa relatively small tubular neck 34, fitting into the tube 32 and communicating with an enlarged portion 35, the inner wall 36 ofwhich tapers in-;
wardly with the same degree of slope as the outward wall of the flange 9, the latter fitting within the cup 33 with a sticking frictional engagement. The cup is preferably transparent. Cumulative Vacuum in the milk vessel 4 is obtained by repeated actuations of the plunger.
The length and resiliency of the tube 32 are such that when the vessel 4 is set upon a table the tube assumes the form of an arch supporting the vacuum pump 1 with its valve end in uppermost position, and when being transported the pump 1 dangles from the tube 32 at a distance from the vessel 4 with its valve end uppermost. This prevents moisture, which may condense upon the inner wall of the barrel or the plunger, from reaching the valve and causing it to become stuck.
The apparatus is designed particularly for self use in maternity wards. It may be expected that some users will tilt the milk vessel or shake its contents, so that a small quantity of milk may occasionally enter the tube 32. The transparency r the cup 33 will enable the attendant to note whether any milk has entered the suction pump 31.
, Since the withdrawn milk is at body temperature, the atmosphere in the vessel 4 is humid, so that moisture may condense in the tube 32. Whether milk or moisture gets into the tube 32, whatever part of it may run into the cap 23 is conducted along the wall of said cap and the contigupus flange 9 of the pump 1 which enters the channel 3|, being excluded from the movable valve parts by the flange H. To .cleanse the channel 3| it is necessary merely to place the finger against the end of the flange I? so as to close the chamber surrounding the valve stem, and to flush the end of the barrel beneath a faucet, The interior of the valve 8 may be cleansed or dried, when necessary, by removing the cap 2|, together with the plunger, and then removing the spring 20. This exposes the inner wall of the barrel, which due to the relatively large diameter of the barrel, is readily wiped off with a cloth or suitable brush.
It is obvious from the above that in all the ordinary manipulations of the apparatus incident to use or cleansing, the inner and outer flanges l6 and. ll adequately shield the valve parts from being contacted by liquid, avoiding the nuisance of sticking, so that no attention need be paid to the valve over long periods of time.
'In its preferred form, the barrel of the pump 7, including the several flanges associated therewith, is an integral molded body of plastic, and the cap with its flange is also a molded plastic body, the only other separate parts being the plunger, valve, the two springs, and the washer which forms the valve seat. The valve and valve stem are an integral plastic structure with the spring retaining ring l slipped on the end of the valve stem after the spring is in place, and adhesively united thereto by a drop of volatile solvent for the plastic, applied to the joint. Should it ever become necessary to remove the valve, 2. drop of penetrant solvent is applied to the joint between the ring and valve stem, which cuts the adhesivebond between these two elements so that the ring can he slipped off.
What I claim as my invention is:
1. Breast pump comprising a flat bottomed milk vessel, a closure for the upper end-thereof supporting a breast applicator and an outlet connection, both in communication with said vessel, a suction pump comprising a barrel having a plunger handle at'one'e'nd and aiperipheral cou-' pling flange at the opposite end, a cross partition within said barrel at the base of said coupling flange having an axial bore, means forming a valve seat on said partition about the inner end of said bore, a valve on said seat having a stem extending through said bore, a valve spring surrounding said valve stem retained thereon and abutting the outer end of said partition, the latter having inner and outer coaxial annular flanges surrounding respectively said valve and said valve spring, the outer of said flanges being spaced from said coupling flange forming a channel, and a connecting member between said outlet connection and the valve end of said suction pump comprising a flexible tube connected to said outlet connection and a coupling cup connected to the opposite end of said tube and detachably coupled to said coupling flange, the length and resiliency of said tube being such as to hold said suction pump positioned with its valve end uppermost when said milk vessel and the plunger handle of said suction pump are resting on a common support, said channel functioning as a depository for liquid which may enter it from the wall of said coupling cup.
2. In a breast pump of the type comprising a flat bottomed milk vessel, a closure for the upper end thereof, a breast applicator and a suction connection supported by said closure and communicating with said vessel, a suction pump comprising a barrel, a plunger within said barrel, having a plunger handle extending beyond said barrel at one end and a peripheral coupling flange at the opposite end, a cross partition within the barrel at the base of said coupling flange having an axial bore therethrough, means forming a valve seat about the inner end of said bore, a valve on said valve seat having a stem extending through said bore and beyond, a valve spring surrounding said stem abutting the outer side of said partition, a collar fixed to said stem at its outer end retaining said valve spring under compression, inner and outer coaxial annular flanges surrounding respectively said valve and said valve spring, said inner and outer flanges being spaced from the barrel to form inner and outer channels, a plunger spring within said barrel seating at one end in said inner channel and at the other end abutting said plunger, a connecting member between the suction connection of said breast pump and the valve end of said suction pump comprising a flexible tube connected to said suction connection, a coupling cup connected to the opposite end of said tube and detachably coupled to the coupling flange of said barrel, said outer flange functioning as a depository for liquid which may enter the valve end of said suction pump from the wall of said coupling cup.
3. Breast pump as claimed in claim 2, said barrel including said cross partition and said inner and outer annular flanges being a unitary molded plastic structure, and said valve, valve stem and collar being a unitary plastic structure with the collar cementitiously united to said valve stem.
PAUL W. SAUNDERS.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 684,078 Martin Oct. 8, 1901 2,208,089 Grolman July 16, 1940 2,276,098 Saunders Mar. 10, 1942