US3039500A - Pipette filling and liquid dispensing device - Google Patents

Description

June 19, 1962 M. GOLDBERG 3,039,500

PIPETTE FILLING AND LIQUID DISPENSING DEVICE Filed Jan. 22, 1959 INVE NTOR MOSHE LEVY GOLDBERG DEZSOE STEINHERZ ATTORNEY.

T nie 3,039,566 Patented June 19, 1962 My invention relates to devices for dispensing liquid in drops or in small quantities, and, more specifically, to devices which discharge liquid from a pipette filled by sucking liquid from a bottle or the like.

Objects of my invention are to discharge the liquid by its own weight under normal atmospheric pressure whereby the liquid will flow more evenly and slowly than it fiows when ejected by pressure, thereby to increase the accuracy of observation and measurement of the dispensed liquid, to regulate the flow by admitting air to the upper level of the liquid through small openings, to make possible selection between the discharge in small single drops and a somewhat quicker discharge, to avoid the necessity of cumbersome and time-consuming adjustment during this selection, to make possible quick succession of filling and discharging operation, and thereby to provide a device adapted to discharge liquid immediately after sucking it into the pipette.

I have found that these objects and advantages can be obtained by a combinationwhich comprises air inlet openings and one or two valves, which can be opened and closed in the manner described hereinafter. The arrangement of these elements will be described later.

Other objects are to affix the pipette to a pipe, through which the sucking of liquid into and discharge of liquid from the pipette is effected, said pipe having a design adapted to attain certain advantages. One of these advantages is to make possible a compact or short shape of the device despite the fact that the pipe must have a certain length in order to accommodate the above mentioned elements whereby storage and handling of the device is facilitated. Another advantage is that the pipette can be located so near to these elements, that its graduation can be conveniently observed during operation of the latter.

Further objects are to facilitate the removal of liquid from the pipette, and to provide, if desired, an opening at its upper end, through which discharge of the liquid can be effected.

Still other objects are to affix the pipette to the pipe exchangeably and air tight, to provide, for this purpose, the pipe with a Widening end and with a rubber lining of this end, and to facilitate attachment and exchange of this lining.

Still further objects are to provide additional means for holding the pipette in proper position, and to make possible quick and easy attachment to and detachment from these means.

Still other objects are to attain these results with simple and reliable means, and to provide a structure that can be inexpensively made and easily operated. Still further objects and advantages will appear from the following description of some specific exemplifying embodiments of my invention, from the appended claims and from the accompanying drawings which show, by way of example, some preferred embodiments of my invention, and in which:

FIG. 1 shows a partly sectional side view of an illustrative embodiment of my invention, the sectionally represented parts being shown in central vertical cross section;

FIG. 2 is a sectional view along line 22 of the device shown in FIG. 1;

FIG. 3 illustrates a modified embodiment of my invention, in a view similar to that in FIG. 1;

FIG. 4 illustrates-in a view similar to that of FIG.

l-a device similar to that shown in FIG. 1, including a valve of modified structure.

Identical parts are denoted by identical reference symbols in the various figures.

The embodiment shown in FIG. 1 comprises a pipe generally denoted 1, which has a part 2 ascending in the drawing, an end part 3, and a bent part 4 connecting the parts 2 and 3. These pipe parts 2, 3, 4 may preferably form a unitary U-shaped tube member. End part 3 has a cross-section widening toward its outer end, as shown in.

FIGS. 1 and 3.

A resiliently compressible bulb or ball 5, consisting of rubber or other equivalent plastic material, is afiixed to the lower end of the pipe part 2. The interior of this bulb communicates with channel 6 which extends through the entire pipe 1. An opening 7 provided in pipe part 2 near the bulb 5, connects channel 6 with the open air. Said opening 7 can be closed air-tight, for example by a ball-shaped closure member 9 which is carried by an arm 8 that is pivotally mounted in a protuberance 10 on the outer surface of the part 2 adjacent the lower end of the part 2 where it is afiixed to the bulb or ball 5.

A little above the opening 7, the pipe 2 has a lateral extension forming a small housing 11. The pipe channel 6 is connected with said housing 11 through an opening which can be closed by a valve by advancing, by turning, the valve stem 12 until it comes in contact with the registering surface of a partition 13 provided in channel 6 of tube part 2. The valve has a threaded stem 12 which passes through the outer wall of the housing 11 and can be advanced by turning button-like handle 14 aifixed to the stem. In the drawing, the valve is represented in simplified manner, and its details may be constructed or designed, in conventional manner.

The widening end 3 of the pipe is provided with a lining of rubber, or the like, 15 which is affixed to the tube in suitable manner. For example, the lining 15 has an extension 16 which reaches out of the pipe about its rim and is bent to engage the outside of part 3.

A pipette 17 has an upper end tightly inserted in the lining 15 whereby this pipette forms a continuation of the pipe channel. The pipette is held disengageably and exchangeably in the lining by resilient pressure. Preferably, the pipette is secured in proper positionadditionally by a clamp comprising two resilient arms 18.

The device shown in FIG. 1 is preferably operated in the following manner:

With valve 12 closed and closure member 9 in open position, the rubber ball 5 is compressed by the operators hand so that the air is expelled from the rubber ball. Opening 7 is then closed so that the rubber ball remains in compressed condition. The free end ofthe pipette 17 is now dipped into the liquid to be dispensed, valve 12 is first opened to the desired extent, and is closed again when the desired amount of liquid has entered the pipette. In order to discharge liquid from the pipette, first closure member 9 is shifted in order to open opening 7 and liquid can be then discharged by opening valve 12 to an extent at which the liquid flows with the desired speed from the pipette.

The modified embodiment of the invention, illustrated in FIG. 3 is generally similar to the embodiment shown in FIGS. 1 and 2, and includes parts 1-18 in substantially the same form as in the device shown in FIG. 1. However, the ascending part 2 of pipe 1, is provided with a second valve which is generally denoted 19 and has a threaded valve stem and a button-like valve handle. Furthermore, the upper end of pipe portion 2 is open and adapted to be closed by a closure member 9 carried by a pivotally movable lever 8" pivoted in a second protuberance 10 on the outer surface of the part 2 adjacent the upper open end thereof.

Operation of the device shown in FIG. 3 is substantially similar to the operation described above of the device shown in FIG. 1. However, second valve 19 can be also used for control of the discharge of liquid from the pipette. Furthermore, by removing closure member 9 from the position shown in FIG. 3, the upper end of tube part 2 can be opened in order to quickly discharge liquid from the pipette.

In the embodiment shown in FIG. 4, the rubber ball 5', and the bent tube 1 form a single unitary piece made of rubber or equivalent plastic material. In a manner similar to that shown in FIGS. 1 and 3, an opening 7' and a pivotally movable closure member 9 for said opening are provided in tube 1'. Instead of the valve shown in FIG. 1, in the upper part of the ascending portion of tube 1, a valve structure of different design is pro vided in FIG. 4. In this valve structure a threaded stem 12' can be advanced and retracted by turning valve handle 14f. Upon advancing said valve stem 12', its end is pressed against the wall of elastic tube 1', which thereby moves to the interior of channel 6 until it contacts the opposite Wall surface and thus shuts off communication between the upper and lower part of tube 1'. This device is operated substantially in the same manner as the device of FIG. 1.

The lining 15 shown in FIG. 1 is unnecessary and is omitted in FIG. 4. v

I desire it understood that my invention is not confined to the particular embodiments shown and described, the same being merely illustrative, and that my invention may be carried out in other ways within the scope of the appended claims. For example, in the embodiment illustrated in FIG. 3, either the opening at the upper end of tube 1 and the accessory parts 8', 9', 10', or the second valve 19 can be omitted. These and other modifications can be made without departing from the scope of the invention as defined in my claims.

What is claimed is:

1. A liquid filling and dispensing device comprising a generally inverted U-shaped pipe, said pipe having a longer leg and a shorter leg that are joined by and are integral with a bent portion that is positioned intermediate of one of the ends of said shorter and said longer legs, a pipette adapted to be afiixed to the other end of said shorter leg, a resiliently compressible bulb connected with the pipe at the other end of said longer leg, said longer leg having a lateral opening adjacent the other end of the longer leg to which said bulb is connected, said opening connecting the channel of said longer leg with the open air, a protuberance on the outer surface of said longer leg in diametrically opposed relation to the opening in said longer leg, a movable arm pivotally mounted. in said protuberance, a ball-shaped closure member mounted on said arm in a position for coaction with said opening, said opening, closure member, and bulb being positioned aside of and near to said pipette, a laterally extending housing on said longer leg intermediate of said bent portion and said opening, a regulating valve positioned in said housing, said valve having a stern extending outwardly of said housing, a handle on said stem in alinement with said opening and said valve being adapted to regulate the communication between the interior of said bulb and the pipette in order to bring about regulated sucking in and discharge, respectively, of liquid to be dispensed.

2. A liquid filling and dispensing device comprising a generally inverted U-shaped pipe, said pipe having a longer leg and a shorter leg that are joined by and are integral with a bent portion that is positioned intermediate of one of the ends of said shorter and said longer legs, a pipette adapted to be afiiXed to the other end of said shorter leg, a resiliently compressible bulb connected with the pipe at the other end of said longer leg, said longer leg having a lateral opening adjacent the other end of the longer leg to which said bulb is connected, said opening connecting the channel of said longer leg with the open air, a protuberance on the outer surface of said longer leg in diametrically opposed relation to the opening in said longer leg, a movable arm pivotally mounted in said protuberance, a ball-shaped closure member mounted on said arm in a position for coaction with said opening, said opening, closure member, and bulb being positioned aside of and near to said pipette, a laterally extending housing on said longer leg intermediate of said bent portion and said opening, a regulating valve positioned in said housing, said valve having a stem extending outwardly of said housing, a handle on said stem in alinement with said opening and said valve being adapted to regulate the communication between the interior of said bulb and the pipette in order to bring about regulated sucking in and discharge, respectively, of liquid to be dispensed, said longer leg of the pipe having an extension at its end opposite to the end connected with the bulb, said extension being provided with a closure member adapted to close and open said extension, and to cause quick discharge of liquid from the device in open position of said member.

3. A liquid filling and dispensing device as claimed in claim 2, in which the longer leg of the pipe is provided with an additional valve positioned between said extension and the regulating valve, said additional valve being adapted to regulate entrance of air to the channel of the pipe.

4. A liquid filling and dispensing device as claimed in claim 1, in which the pipe as well as the bulb consists of a rubber-like plastic material and forms a unitary structure and the valve is adapted to completely constrict the piplei by causing the valve stem to press against the pipe wa References Cited in the file of this patent UNITED STATES PATENTS 1,679,104 Trautman July 31, 1928 2,540,360 Ulvild Feb. 6, 1951

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