US2558043A - Dispensing apparatus - Google Patents

Description

June 26, 1951 R DELQR 2,558,043

DISPENSING APPARATUS Filed May 27, 1946 INVENTOR. RAYMOND A. DELQ R Patented June 26, 19 51 DISPENSING APPARATUS Raymond A. Delor, Kalamazoo, Mich., assignor to The Upjohn Company, Kalamazoo, Mich., a corporation of Michigan Application May 27, 1946, Serial No. 672,565

6 Claims.

liquid dispensing apparatus, and more particularly to apparatus adapted to dispense automatically a predetermined amount of liquid during each cycle of operation.

In the manufacture and packaging of liquid. pharmaceutical preparations, it is common practice to employ bottle filling machines comprising, as a part of their mechanism, a reciprocating syringe which, through suitable connections and valves, automatically and continuously effects the alternate withdrawal of a predetermined amount of liquid from a reservoir and the discharge thereof to a bottle filling needle or similar outlet.

The type of syringe employed in apparatus of this character usually consists of a glass cylinder and a cooperating, reciprocable glass piston or plunger, the cylinder being provided at one end with a small intake and discharge orifice and the opposite end being open to receive the piston. As the piston is partially withdrawn a predetermined distance from the interior of the cylinder, an exact amount of liquid will thus be induced therein from the source of supply and when the piston is moved into the cylinder, the liquid therein will be forced out of the discharge orifice to the filling needle and thence to the bottle or other container. However, in the syringes of this type, there constantly occurs a small amount of fluid leakage from the cylinder past the walls of the piston as it reciprocates therein. As the liquid thus adhering to the piston wall is brought into contact with the atmosphere, a certain amount of evaporation takes place and a crystalline or other solid residue which is formed as a result of such evaporation begins to adhere to and build up on the piston. It Will be obvious that if any appreciable accretion of this nature is permitted, the encrusted, and thus enlarged piston, being positively driven into the cylinder, will cause a breakage of the parts with the attendant expense, inconvenience and loss of time.

In order to prevent a prohibitive amount of breakage from this source, it is now the practice for the operators of these machines periodically to spray water or other liquid under pressure onto the piston as it reciprocates. This must be done frequently to prevent any appreciable accumulation and requires a great deal of attention by the operator, taking the time from the regular operation of his machine and attendant duties.

formance of this function, sufiicient evaporation and crystallization will occur to cause a breakage of the parts as previously pointed out.

Further, inasmuch as at least a portion of the piston reciprocates from within the cylinder out into contact with the atmosphere and back again, there is continuous danger of contamination from the atmosphere of material within the cylinder.

Accordingly, the present invention has for primary objection the provision, in a liquid dispensing apparatus employing a cylinder and piston, of means for preventing evaporation of liquid and the resulting injurious accretion of solids on the relatively movable parts.

Another object of the invention resides in the provision of means to seal the fragile moving parts of aliquid dispensing syringe against atmosphere contact.

Still another object of the invention is to provide, in a liquid dispensing apparatus employing a cooperating cylinder and reciprocatin piston, a liquid filled jacket surrounding the exposed portion of said piston to effect an atmospheric seal.

Other objects and advantages of the invention will become apparent from a reading of the following description taken in connection with the accompanying drawings, in which:

Figure 1 is a vertical sectional view of the por tion of the apparatus comprising the present invention and showing a bottle filling needle and its associated parts, which may be employed with the apparatus, and

Figure 2 is a partial elevational view showing the essential parts with which the present invention is employed.

Referring now to the drawings and particularly to Figure 2 thereof, the apparatus to which my invention is applied for illustrative but not limit-,-

ing purpose generally comprises a housing It) which may enclose a suitable source of power such as a variable speed electric motor con-' nected in any well known manner to drive a crank shaft having an eccentric crank pin H extending through a wall of the housing l0 and which in turn carries a relatively rotatable, two part bearing member l2. A bracket 13 is positioned exteriorly of the housing It and car ries a vertically adjustable fluid header I 4 having an angularly extending arm l5 adapted to carry in threaded relationship liquid inlet and outlet fittings I l and I 8 which communicate with a liquid reservoir (not shown) and a bottle filling needle I9, respectively, through suitable flexible hose connections 2! and 22.

Theelectric motor may be provided with a suitable speed con-'- trol having a knob and dial 20 positioned exteriorly of the housing 49.

As shown in Figure 1, the fluid header is provided with a transverse fluid passageway 23 in open communication adjacent one end thereof with fluid passageways 24 and 26 formed in the fittings l1 and I8, respectively. The fittings l1 and I8 are provided with extensions 2? and 28 forming nipples to receive the flexible couplings 2| and 22. The extensions 2? and 28 are also formed with fluid passageways 29 and 3! communicating with valve chambers 32 and-33. which contain spring pressed needle valves 34 and 36, respectively.

A fitting 31 may be screwed into the lower face of the header l4 and is provided with a fluid passageway 38 communicating with the transverse passageway 23 in the header. This fitting 31 carries a sleeve 39 which in turn supports a syringe cylinder 49 having an inlet and discharge orifice 4| communicating with the passageway 23 in the header l4 through the passageway 38. The opposite end or mouth of the cylinder 40 is open to receive a cooperating reciprocable plunger or piston 42 which, at its lower end, is provided with a neck and radially extending flanged portion 43 forming an enlarged, cylindrical base by means of which the piston is connected for reciprocation by the crank.

. The crank pin bearing i2 is provided with an integrally formed, upstanding boss 44 through which reciprocating motion is imparted to the piston 42. The lower end of the piston 42 may be secured to the boss 44 for movement therewith by means of a split-ring 46 positioned around the neck of the piston 42, overlying the flanged portion 43 thereof and provided with an outwardly radially extending flange 41. The boss 44 on the crank pin bearing i2 is associated with an upwardly extending sleeve 48 having an inwardly extending flanged portion 49 adapted to overlie the radial flange 41 of the split-ring 45 carried by the piston. It will be understood that as the crank pin H carrying the bearing 12 and boss 44 moves downwardly the piston 42 will be withdrawn from the cylinder 49 to substantially the position shown in Figure 1. The upward thrust of the crank pin l l istaken by the enlarged base portion 43 of the piston and, to prevent the escape of the hereinafter mentioned sealing liquid,

From the description thus far, it will be apparent that as the piston 42 is partially withdrawn from the cylinder 45 to the position shown in Figure l, a predetermined quantity of liquid will be withdrawn from the reservoir through passageway 29, the valve chamber 32, passageway 24, transverse passageway 23 and passageway 38 into the syringe cylinder 40. Upon further rotation of the crank, the piston 42 will be moved upwardly within the cylinder 49 forcing the liquid therein out through the cylinder orifice 4|, passageway 38, transverse passageway 23 to passageway 26, through valve chamber 33 and passageway 3i and to the bottle fillin needle l9 through the flexible coupling 22. As the crank is further rotated, this cycle of operation is continuously repeated.

' As the piston 42 continues to reciprocate in and out of the cylinder 49, a small amount of liquid will, in conventional operation, constantly leak past the piston through the open end of the cyl- 4 inder 49, will adhere to the walls of the piston and, during each downward stroke thereof, be brought into contact with the surrounding atmosphere, whereupon evaporation will take place and a crystalline or other solid substance will adhere to and build up on the walls of the piston. If accretion of this nature is permitted to continue, it will be obvious that the effective diameter of the piston will be materially enlarged so that breakage of the cylinder 49, and often the piston itself, will soon occur.

To obviate this serious objection, I propose to provide a casing surrounding the piston and a portion of the cylinder and to fill the chamber formed thereby with a suitable liquid, such as water, forming an eiiective seal against contact of these parts with the surrounding atmosphere. To accomplish this end, a cylinder 52, of substantially greater diameter than the syringe cylinder 40 or piston 42 and open at both ends, is positioned in coaxial, radially spaced relation with respect to the cylinder 49 and piston 42 and is supported at its lower end for vertical reciprocating movement upon the outer annular shoulder 59 of a relatively stifi rubber sealing sleeve 53. The sleeve 53 is provided at its upper end with an inwardly extending flanged pore tion 54 over-lying the flange 49 of the sleeve 48 and is formed at its opposite end with an in-. wardly turned lip 55 adapted to engage the lower peripheral edge of the boss 44 in liquid sealing relationship thereto. To further seal the interior of the casing 52 and reduce the possibility of atmospheric contamination of the liquid being dispensed, a flexible rubber sleeve 55 may be positioned between the upper end of the casing 52 and the upper end of the syringe cylinder 49 and secured as by split, resilient, or other retainer rings 51 and 58. The wall section of this sealing sleeve 56 is sufficiently thin to permit flexible distortion thereof when the liquid filled casing 52 is moved upwardly from the position shown in Figure 1.

As shown in Figure 1, the bottle filling attachment may conveniently comprise a sleeve 59 extending substantially coaxially with the filling needle 19 and adapted to be readily slipped over the mouth and a portion of the neck of a bottle BI, and the needle [9 may be positioned centrally of the sleeve 59 by a suitable stopper 62 through which the needle extends.

The quantity of fluid delivered on each stroke is determined by suitable adjustment of the length of each stroke. This adjustment is made in any convenient manner, as by adjusting the radius of the circle (by means not shown) described by the crank pin l l.

With the syringe cylinder 40 carried by the header in the manner above described, vertical adjustment thereof, as previously described, on the bracket is will vary the relative position of the cylinder with respect to the piston 42, wheree by there may be efiected suitable cooperation of the cylinder 49 with the piston 42 as the length of piston stroke is adjusted.

From the above description, the operation and advantages of the invention will be readily ap parent. As the crank is rotated and the boss 44 is moved to reciprocate the piston 42, the liquid casing 52 Will likewise be reciprocated through the medium of the sleeve 48 and the rubber sealing sleeve 53. On the upstroke, the flexible sealing sleeve 55 will partially collapse to permit such movement and on the downstroke the parts will assume. the relative positions as shown in Figure 1. The outer cylinder or jacket 52 is filled with water, or other suitable liquid, so that the otherwise exposed portion of the piston 62 is at all times throughout its cycle of reciprocation effectively sealed against atmospheric contact and, accordingly, evaporation of the liquid being dispensed and the subsequent accretion of solids on the walls of the piston, as well as possible contamination of the liquid being dispensed, are effectively prevented.

It will be evident that the flexible sleeve 56 may be omitted without affecting the protection afforded by the device against evaporation of liquid on the syringe piston the sole purpose of this part being to protect the sealing liquid from pos sible atmospheric contamination. The entire syringe portion of the apparatus may be quickly removed from the header M for sterilization by merely rotating the sleeve 39.

The invention may evidently be applied to other forms of syringe utilizing machines, such as those operated by pressure and cooperating resilient means, and the above description in connection with power operated means should be understood as illustrative and not limiting.

While various modifications in construction and design will readily suggest themselves to those skilled in the art, it should be understood that the invention is to be limited only by the spirit and scope or the appended claims.

What is claimed and desired to be secured by Letters Patent is:

1. In combination with an apparatus for dispensing liquid supply, a syringe connected to said source of sup-ply comprising a cooperating cylinder and piston, power driven means connected to reciprocate said piston, a casing mounted on, and for reciprocation with, said piston and having a liquid therein surrounding a portion of said cylinder and piston and in contact with that portion of said piston which extends outwardly of said cylinder, and hydraulic sealing means resistive to passage of said liquid between said casing and said cylinder and piston.

2. In an apparatus for dispensing liquid having a source of liquid supply, an adjustably mounted fluid header connected to said source of supply, a syringe comprising a cylinder carried by said header, a piston reciprocably associated with said cylinder, power driven means connected to reciprocate said piston, a fluid filler casing surrounding a portion of said piston and mounted for reciprocation therewith, a liquid within said casing surrounding said cylinder and said piston and in contact with that portion of the piston immediately outwardly of said cylinder; an atmospheric seal resistive to atmospheric penetration between said casing and said cylinder, and a hydraulic seal resistive to passage of said liquid between said casing and said power driven means.

3. In a device for pumping a liquid containing normally solid substances in solution therein and including a syringe plunger operating in cooperation with a syringe cylinder, means for simultaneously lubricating and cleaning said plunger comprising in combination: a cylindrical casing concentric with, and spaced radially outwardly from, said plunger having one end axially adjacent that end of the plunger which is outside of said cylinder and extending in a direction for telescoping the said plunger a distance greater than the stroke of said plunger; liquid tight means mounting said casing to said end of said plunger for positive reciprocating movement therewith; said syringe and associated casing being arranged substantially vertically with the fluid receiving and discharging end of said syringe uppermost; a liquid within said casing which liquid comprises a solvent for said normally solid material; whereby said liquid will surround the portion of said plunger extending outward from said cylinder during all parts of its reciprocation cycle and said liquid will both prevent the exposure of said plunger to the atmosphere and will hold in solution any of said normally solid material which may be thereon.

4. The invention defined in claim 3 having also a flexible membrane closing the annular space between the free and uppermost end of said casing and an adjacent portion of said syringe whereby atmospheric contamination will be prevented from reaching said liquid.

5. In a device for pumping a fluid and including a plunger operating in cooperation with a cylinder, means for lubricating said plunger comprising in combination: a casing concentric with and surrounding said plunger, having one end axially adjacent that end of the plunger which is outside of said cylinder and extending in a direction for telescoping the plunger a distance greater than the stroke of said plunger; liquidtight means mounting said casing through said end of said plunger for positive reciprocating movement therewith; a liquid within said casing, said liquid being present in sufficient quantity to cover entirely during all positions of said plunger with respect to said cylinder the portion of said plunger which is outwardly of said cylinder; whereby said liquid will both prevent the exposure of said plunger to the atmosphere and will effect complete lubrication thereof.

6. In a device for pumping a liquid containing normally solid substance in solution therein and including a plunger operating in cooperation with a cylinder, means for simultaneously lubricating and cleaning said plunger, comprising in combination: a casing concentric with and surrounding said plunger, said casing telescoping said plunger and a portion of said cylinder radially outwardly of each thereof and mounted on said plunger in liquid-tight association therewith a liquid comprising a solvent for said normally solid substance within said casing, said liquid being present in sufiicient quantity to cover entirely during all positions of said plunger with respect to said cylinder the portion of said plunger which is outwardly of said cylinder; whereby said liquid will both prevent the exposure of said plunger to the atmosphere and will hold in solution any of said normally solid material which may be thereon.

RAYMOND A. DELOR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 19,671 Atwater Mar. 23, 1853 54,399 Patric May 1, 1866 756,630 l-Iernenway Apr. 5, 1904 1,486,498 Smith Mar. 11, 1924 1,546,595 Mader July 21, 1925 1,724,553 Bennett Aug. 13, 1929 1,737,387 Redmond Nov. 26, 1929 FOREIGN PATENTS Number Country Date 12,090 Great Britain .1900

571,166 France 1924

Images