US3362343A - Liquid dispenser - Google Patents

Description

O. H. DUDA LIQUID DISPENSER Jan. l9, 1968 Filed March 1, 196e United States Patent 3,362,343 LIQUID DISPENSER Otto H. Duda, Hacienda Heights, Calif., assigner to Calmar, Inc., City of Industry, Calif., a corporation of California Filed Mar. 1, 1966, Ser. No. 530,855 16 Claims. (Cl. 103-178) This invention relates to improvements in liquid dispensing pumps of the type generally disclosed in the Corsette Patent No. 3,228,347, of common ownership herewith.

The aforesaid application disclosed dispensing pumps adapted for application to portable containers in which various liquid products are sold and in which the pumps are particularly adapted for application to the -lilled containers at the factory to 4be sulbsequently sh-ipped with the lled containers to suitable sources of distribution.

It is particularly important, therefore, that such dispensers be equipped with suita'ble shipping seals adapted for preventing leakage of the liquid, either through the pump discharge passages or between the pump cylinder and plunger, incident to rough handling or inversion of the containers. It is also desirable that such shipping lseals ybe effec-tive in either the fully-projected or the fullydepressed position of the plunger so that the same basic pump structure may 4be shipped with the plunger in either position, except that where the pump and its associated container are to be shipped with the plunger in its fullyprojected position, the usual means for locking it in a fully-depressed position may be omitted.

It is an object of the invention to render a reciprocating pump type dispenser capalble of achieving the foregoing ends and also to adapt it yfor economical production and assembly. Also, it is an important object of the present invention to provide an improved pump structure capable of attaining the foregoing ends by means of a relatively-reduced number of parts, and also capable of other important advantages.

-In accordance with the present invention, there is provided a fricti-onal coupling or telesc-oping clutch connection between the plunger and the inlet valve stem. This connection is rendered operative only near the extremity of the plunger retraction movement (on its suction stroke) to transmit a seating force to the inlet valve upon inception of the next-ensuing compression stroke of the plunger. Such frictional coupling is established by frictional reception of an enlargement of the valve stem in a constricted portion of the plunger discharge passage.

It is a yfurther important feature of the invention to make dual utilization of the said clutch structure, both for clutching purposes and also as a sealing valve which is automatically closed and open incident to the engagement and disengagement of the clutch, thus to automatically establish a shipping seal in the fully-projected plunger position.

Further, there is provided an additional frictional connection or coupling between the plunger and inlet valve, established only as the plunger nears its fully-depressed position. This coupling, which is estab-lished incident to the complete depressing Iof the plunger, opera-tes to exert an unseating force on the pump inlet valve on the inception of the next suction stroke of the plunger and is automatically discontinued after but a brief projection movement of the plunger in order to -avoid interference with the continued plunger movement.

It is a further feature of the invention that this additional frictional connection also may serve the function of a sealing valve or plug operative in the fully depressed position of the plunger.

Thus, where -both of the dual-acting frictional cou- Patented Jan, 9, 1968 plings and sealing valves are employed, the inlet valve is both seated and unseated by movement of the plunger from either extremity of its movement; and, in addition, the plunger discharge passage is effectively sealed when the plunger is at either extremity of its movement.

Moreover, there is contemplated an advantageous disposition of the sealing valve for relative movement between axially-sp'aced por-ts in the discharge passage of the plunger, incident to reciprocation of the latter, and for alternate seat-ing Irelative to these ports at opposite extremities of the plunger movement, to thus provide effective shipping seals at either extremity of the plunger movement.

In accordance with certain specific but advantageous 4features of the invention, the sealing valve is so associated with one of its said sealing ports yas to be capable of ybeing forced there-through to an operative position between the alternate ports, thus facilitating assembly of these parts. Also, provision is made for simultaneously seating of the inlet valve and the sealing valve by direct engagement between the sealing valve and a plunger seat or port in the fully-depressed position of the plunger and for maintenance of a constant resilient seating pressure of both of these valves with `their associated ports by forming either or both of the valve seats around said ports of elastically expansible material, to be expanded by seating therein of conical portions of the sealing and/or inlet valves.

The invention also provides an improved external seal (that is, a seal externally of the plunger between the plunger and -cylinderl in which the seal is rendered operative only at the extremity of the plunger movement and is rendered inoperative throughout the major portion of the plunger stroke in either direction, -both to avoid impeding the plunger stroke and also to establish communication of the container interior with the exterior atmosphere so as to permit the entry of air to take the place of liquid removed by the pump.

To this end, the invention employs a novel arrangement of sealing ring or gasket which encircles the plunger rod and is interposed between ythe plunger rod and cylinder. The plunger rod is formed to cooperate with the said sealing ring in lthe manner of a slide valve and, for this purpose, is formed with suitably-positi-oned enlargements adapted to enter the sealing ring, preferably at fboth extremities of the plunger movement, so as to compress the ring radially between the opposed Wall portions of the cylinder and plunger. Between such enlargements, the plunger rod is Ifo-rmed to permit a suicient flow or seepage of air for venting purposes.

A preferred embodiment of the invention, incorporating the various features and advantages above enumerrated, is illustrated -by way of exemplication in the accompanying drawings in which:

FIGURE l is a sectional view in an axial plane through a reciprocating pump structure in accordance Iwith the invention wherein said structure is supported in a heretofore-known manner in a container closure. In this figure, the plunger of the pump is in its fully-projected position;

FIGURE 2 is a view similar to FIGURE l, but with the plunger secured in its fully-depressed position; and

FIGURE 3 is a section on the line 3--3 of FIGURE l showing certain details of the inlet valve construction.

The accompanying drawings and the ensuing detailed description are lby Way of exemplication only for the purpose of disclosing what is -presently contemplated as 'the best mode of practicing the invention. It will accordingly be understood that the description and accompanying drawings both will involve details which may be omitted or changed, as those skilled in the art will understand, without departing from the spirit of the invention.

Referring now in detail to the structure shown in the accompanying drawing, same illustrates a reciprocating pump in which the several elements or components, broadly speaking-cooperate in conventional manner to achieve the pumping action, and, in addition, incorporate certain new structural features, advantages and modes of cooperation as later described.

Considering first the general organization of elements, the pump structure is adapted to be supported in the outlet of a liquid container to dispense the contents thereof. Accordingly, the pump cylinder 10, which is here exemplified as the stationary portion of the pump, is provided with a conventional fianged collar 12 at its upper end. This collar 12 extends through and supports the pump cylinder within an opening defined by the top wall 13 of a container closure, here illustrate-d as provided with a depending internally-threaded skirt 14 4for application in usual manner to the externally-threaded neck or spout of a bottle or other usual container, not here illustrated. The upper and lower fianges 16 and 17 respectively of the collar 12 project above and below the closure top wallr13 to secure the collar in place within the central opening lof the closure wall 13, the upper flange 16 being formed, preferably Iby a swaging action in known manner, after the collar has been inserted through the opening to bring the pre-formed flange 17 into abutment with the lower surface of the top wall. It will be apparent that the threading of the closure 13 onto the container will clamp to the lower fiange 17 against the upper end of the container neck or spout. The annular sealing rib 1S of the lower flange exemplifies any conventional means for providing fluid-tight engagement of the flange 17 with the bottle neck.

It will thus be seen that the major portion of the pump cylinder 10, as well as of the pump in its entirety, will normally be housed within the container with its lower end communicating with the container contents through an axially-directed inlet port 20 which, in the preferred embodiment, is defined by the elastically-stretchable or deformable upper end extension 21 of the dip tube 22 through which the inlet port 20 is placed in communication with the lower end portion of the container so as to be capable of withdrawing substantially the entire liquid contents therefrom. An inlet valve 23 permits the flow of liquid upwardly through the inlet port 20 and prevents its downward flow from the pump chamber 30.

The reciprocable portion 25 of the pump here shown is exemplified by the tubular plunger, generally designated 25, and including a hollow plunger rod 26 which is received with substantial clearance in the cylinder 10, together with the anular piston 27 of relatively-greater diameter having an outwardly and downwardly-flaring skirt 28 in operative wiping engagement with the inner wall surface of the cylinder to define a variable volume pump chamber 30 in the lower end portion of the cylinder between the piston 27 and the inlet port 20` in the lower end wall of the cylinder. The passage 29 through the plunger opens upwardly thereinto from the pump chamber 3f) into communication with other passages leading to the outlet or discharge orifice of the plunger, as hereinafter described.

The plunger 25 is resiliently projected upwardly on its suction stroke by the coil spring 31 which encircles the lower end extension 32 of its plunger rod 26 and is compressed between the piston 27 and a spring seat 33 jointly defined by the axially upwardly-presented ends of a series of annularly-arranged and relatively circumferentially spaced splines 34 formed integrally with and projecting radially inwardly from the inner wall of the cylidner concentrically to the inlet valve port 20. Disposed for axial sliding movement between the respective splines 34 are the splines or keys 35 of a peripherally-splined disc 36 projecting radially outwardly beyond the base of the conical valve body 24 and preferably afiixed thereto as an integral portion of the valve. The splines 35 thus extend radially outwardly beneath the lower convolution of the plunger spring 31, which thus serves as a stop -for limiting the unseating movement of the inlet valve 24.

Upward movement of the plunger on its suction stroke, under the expansive force of the spring 31, is limited by engagement of the upwardly-directed annular shoulder or abutment 37 of the plunger with a suitable stop element such as the sealing ring 38. The sealing ring 38 is secured against axial upward displacement in the cylinder by reception within the inwardly-opening groove or annular seat 39 internally of the cylinder.

The plunger rod 26 extends upwardly for axial movement through the sealing ring 38 and the open upper end of the cylinder 10 for actuation in conventional manner by intermittently-applied finger pressure against its upper end. The plunger 25 includes at its upper end a generallyconventional plunger discharge head 40, which may tbe constructed in a manner heretofore known and formed to provide an upwardly presented button or fingerpiece 41 adapted to receive the actuating finger pressure. In the form here shown, the plunger discharge head40 is fabricated separately from the rest of the plunger, as an integral plastic molding having a blind socket 42 to be fitted yover the upper end of the plunger rod 26 in snug fiuid-tight relation therewith and secured in place thereon, as `for instance by means of cooperating snap rings and grooves 43.

The plunger head here shown is in the form of a spray head and to this end is formed with a restricted spray discharge orifice 45 communicating with a swirl chamber 46 which, in turn, is supplied with fluid through a groove 47 from the inner end portion of the socket 42. This groove or passage 47, in turn, communicates with the axial passage 29 through the plunger. The said intercommunicating passages jointly define the plunger discharge passage leading from the pump chamber upwardly to and through the discharge orifice 45.

It will be readily apparent that the inlet valve 23, in addition to its modes of operation as hereinafter described, also is adapted to function in the manner of a conventional check valve, to open in response to suction created by the up-stroke of the plunger whereby to admit liquid through the inlet port 20r into the pump chamber 30 and to be seated by pressure created Within the pump chamber on the compression stroke of the plunger.

While the function of an upper check valve may be served by the restricted orifice 45 of the spray head in a manner well known in the art, it will generally be desirable to achieve somewhat greater efiiciency through provision of such a check valve 48, in cooperation with the valve seat 5t) within the plunger. The stop finger 51, depending from the plunger head into the upper end of the axial plunger passage 29, limits the unseating movement of the valve 48.

In order that the hereinafter-described interior and exterior shipping seals may be securely maintained when the pump and its associated liquid container are conditioned for shipping with the plunger in its fully-depressed condition, there may be provided any suitable means for thus releasably holding the plunger fully depressed.

The means herein illustrated for purposes of exemplication are conventional, and comprise an externallythreaded plug 55 at the base of the plunger head 4t)l for cooperating reception in the internally-threaded collar 12 of the cylinder 10.

The plug 55 is also illustrated as being provided with radially and axially-projecting annular seals 56 and 57 respectively for engagement with cooperating sealing surfaces of the collar, all in a manner now well known. However, since such seals and their function are merely cumulative to the function of the exterior sealing means more fully hereinafter described, it will be appreciated that the seals 56 and 57 are merely optional.

Referring now in more detail to the particular valve actuating and sealing features constituting the subject matter of the instant invention, it will be noted that'the inlet valve 23 is provided with an axially upwardly-directed and substantially-rigid valve stem 58 which projects axially into the discharge passage 29 of the plunger, and is freely movable in such passage through a sealing valve port 59, through which it passes with sufficient clearance as to permit substantially unimpeded uid flow. Carried at the free end of the valve stem 58 is a sealing valve 60 which is positioned for alternate seating at opposite extremities of the plunger movement with the sealing port 59 and with the further sealing port 61. Port 61 is spaced axially along the passage from the port 59 at such a distance as to cause said ports to cooperate with the valve 60 at opposite extremities of the plunger movement, it being apparent that the latter is movable within predetermined limits .governed by the engagement of the plunger with the inlet valve on the one hand and by the abutting engagement between the annular plunger stop surface 37 and sealing ring 38 on the other hand.

In order to adapt it for alternate cooperation with the specific types of valve ports designated at 59 and 61 respectively, the valve 60` is provided with a conical upper end portion 60a converging toward the port 61 and adapted for sealing reception therein. The port 61 in the present instance is defined by the lower end of a sleeve 62 depending from and constituting an integral portion of the valve seat 50, and of an elastically-expansible material such that the valve seat defined by the lower end of the sleeve 62 at port 6-1 is circumferentially expanded by sealing reception of the conical valve portion 60a. The seating pressure between these parts is transmitted through the valve stem to the inlet valve 23, and the oppositelydirected and elastically-expanded valve seats operate in similar manner in conjunction with their conical valve portions 6a and 24 respectively to maintain a constant resilient seating engagement with these portions as long as the plunger is locked in its fully-depressed position.

For cooperation with the valve port 59 (which may be seen to constitute a constriction defined by the mutuallyconverging conical passage portions 63 and 64 within the plunger passage 29), the sealing valve 60 is provided with la substantially-cylindrical portion 60h proportioned for snug frictional sealing reception in the port or constriction 59. A tapered pilot portion 60C of the sealing valve 60 extends from the cylindrical portion 60h toward the constriction 59 to guide the enlarged portion 6G17 into the constriction of port 59.

It will be apparent that the sealing valve 60 will seat in the port 59 when the plunger is fully projected to the upper or outer limit of its stroke by action of the plunger spring 31, the upward movement of the valve 60 having been previously arrested by cooperation of the spring 31 and splined disc 34. Moreover, by virtue of the relationship of the sealing valve 60 and the constricted port 59, it Vwill be apparent that the valve 60 may be readily assembled in operative position for movement between the two ports or seats 59 and 61 simply by inserting it into the lower or inner end of the plunger passage and forcing it through the constriction 59.

In addition to its valving function, the valve 60 cooperates with the constricted port or seat 59 to establish a frictional coupling between the plunger and the inlet valve at the end of each suction stroke of the plunger, so that, at the inception of a downward or compression stroke of the plunger, its movement is frictionally transmitted to the inlet valve 23 to seat same. The frictional coupling will be disengaged by continued downward movement of the plunger.

A further frictional coupling between the plunger 25 and valve 23 for unseating of the conical valve portion 24, at the inception of the upward or suction stroke of the plunger from its fully-depressed position as shown in FIGURE 2, is provided by means of a cylindrical plug 65 carried by and preferably formed integrally with the valve 23. This plug 65 is proportioned for snug frictional reception in the lower end of the plunger passage 29 below the piston 27. This plug 65 also is preferably provided with a conical guide portion 66 to facilitate its entry into the passage incident to the downward movement of the plunger. Thereafter, when the plunger is released to commence its up-stroke, the frictional coupling thus established between it and the inlet valve 23 exerts an unseating force on the latter until such coupling is disengaged by abutment of the splined disc 36 with the plunger spring.

The thrusting engagement of the valve seat 61 at the lower end of sleeve 62 with the sealing valve 60 exerts a positive seating force which is transmitted to the inlet valve 24 through its stem 58. However, it may be desirable in some instances to duplicate this seating thrust by extending the lower end of the plunger rod 26 to cause it to press axially against the upper face of the inlet valve disc 36 in the fully-depressed position of the plunger. In addition, it will be apparent that the relatively-thicker and heavier plunger extension 32 cooperates with the relatively lighter and resiliently or elastically expandable lower end of the sleeve 62 to gauge and limit the expansion of the latter by affording a positive limit for relative downward movement of the plunger onto the seated inlet valve 24.

It will be apparent that the several parts of the pump other than the plunger spring itself may Ireadily be formed by conventional plastic molding processes from various plastic materials, as for instance polyethylene, having sufficient qualities lof flexibility and elasticity to function as above described. The construction and arrangement of the interior seals having thus been fully described, reference will now be made in greater detail to the preferred construction and operation of the exterior seals.

Such exterior seals comprises the combined sealing ring and plunger stop 38 which, as earlier mentioned, encircles the plunger 25 and is positioned in the cylinder 10 within a groove 39 by which it is secured against substantial axial displacement when engaged by the reciprocating plunger.

The upper end wall of the groove 39 preferably is of substantial radial extent to afford a positive limit for preventing upward displacement of the ring 38, and, therefore, in the preferred embodiment, is formed by an integral inwardly projecting radial rib 68 within the pump cylinder adapted for reception of the plunger with a slight clearance.

In order to adapt the ring 38 for positioning within the groove 39, the ring 38 may be formed of a material such as natural rubber, polyethylene, or the like, capable of being sufficiently deformed to permit its insertion downwardly through the rib 68 and adapted thereafter to expand outwardly into resilient sealing engagement with the bottom of the groove 39.

The pump barrel is provided with a usual vent or opening 69 above the piston 28 and preferably just below the ring 38 to permit the escape back into the container of any liquid which might have :become trapped in the cylinder above the piston 27 and such as might, in the absence of a vent, interfere with the movement of the plunger as well as cause upward leakage of liquid past the sealing ring 38. For venting the interior of the container to the atmosphere so that it may normally be substantially at atmospheric pressure during the pumping operation, the portion 71 of the plunger which -moves through the sealing ring 38 throughout the major part of the plunger stroke in either direction, is of sufficientlyreduced diameter relative to the ring as to have a slight clearance therewith, as is apparent in FIGURE l. Accordingly, when the plunger is in various intermediate positions between the extremities of its stroke, communication is establishedbetween the vent 69 and the atmosphere between the inner periphery of the sealing ring 38 and the plunger rod, through the open upper end of the cylinder.

At opposite axial ends of the reduced plunger portion 71, the plunger is formed with cylindrical enlargements 72 and 73 respectively positioned for sealing reception in the ring 38 at opposite extremities of the plunger movement.

The ring 38 is adapted for limiting and sealing engagement with the plunger in the upwardly-projected position of the latter, in the manner exemplified in FIG- URE l, in which the sealing ring is shown to be axially compressed between the annular stop rim or ledge 37 of the plunger and the stop rib y68 within the cylinder. While the stop ring 38 may assume various forms, it has been found that one suitable cross sectional shape of the ring is as illustrated, in which the sarne is provided with radially-inner and outer pairs of relatively upwardly and downwardly diverging conical skirts 74, 74', 75, '75 respectively, connected to each other and to the main body of the ring 38 along a radial plane midway of the axis of the ring. These radially-opposed pairs of skirts are arranged so that the radially outer peripheries of the skirts 75, 75 Will normally be deflected somewhat radially inwardly by and seal against the `bottom of the groove 39, While the inner peripheries of the respective skirts 74, 74 are proportioned for sealing engagement with the respective plunger enlargements 72 and 73 and for clearance with the reduced intervening plunger portion 71. The ring also comprises oppositely axially-diverg ing pairs of conical skirts 76, 76 and 77, 77 of which the radially outer and radially inner such skirts 76 and 77 respectively are adapted for sealing engagement with I the rib 68 and with the annular sealing ledge or shoulder 37 of the plunger. Thus, in the fully spring-projected position of the plunger, the sealing ring 38, in addition to its function as a stop for determining such position, has both of its sealing skirts 75, 75' and also its skirt 74 in resilient radial sealing engagement with the cylinder and plunger respectively, while its upper and lower skirts 76 and 77 are in axial sealing engagement with the stop rim 68 and stop ledge 77 respectively. Rather than form the ring with separate sets of skirts for separate radial and axial sealing engagement with the plunger, the sealing ring may be formed to omit the skirts 76, 76', 77, 77', and to utilize the remaining skirts 74, 74' and 75, 75' for both purposes. Obviously the sealing ring is capable of other cross sectional forms as will be obvious to those skilled in the art.

The linvention in its preferred form is capable of assembly from a small number of parts which, except as to the plunger spring and ball check Ivalve, are adapted to lbe molded in conventional manner of usual plastic materials.

The cylinder may be formed of a comparatively rigid plastic material and assembled to the container cap in conventional manner by pressing or swaging the rib 16 therein after insertion of the collar portion through the opening within the container closure. The castellated shoulder 78 which is formed externally around the cylinder in accordance with conventional practice affords means for supporting the cylinder within the conventional tool both to withstand both axial thrust imposed thereon incident to the swaging of rib 16 and the torsional force incident to holding the cylinder 10 against rotation where, after assembly of the several parts, the pump plunger is locked in its fully-depressed position by simultaneously depressing and rotating same with its externally-threaded plug 55 engaged in the threaded collar 16.

Although various modes and orders of assembly of the pump components will be apparent, it may be noted by way of illustration that inlet valve 23 is capable of assembly within the cylinder merely by dropping it downwardly into the cylinder through the open upper end thereof, following which the spring 31 may similarly be dropped into position around the stem of the valve 23. After insertion of the stop ring 38 into position, same may be resiliently expanded to permit insertion of the plunger. The flexible piston skirt will at the same time be radially compressed to pass through the ring. Even though the splines or keys may not initially have registered with the spaces between the splines 34 of the spring seat, the saidsplines will nevertheless be brought into registry with each other by rotation of the plunger, which will be transmitted through the frictional connections established between the plunger and inlet valve at either extremity of the plunger movement.

Formation of the internal stop rib 68 within the cylinder is preferably deferred until after insertion of the plunger. The plunger components, namely the ball check valve 48 and plunger discharge head 40, may be assembled after the assembly of the plunger and cylinder, and the swaging of the stop rib 68.

OPERATION Plzmger fully depressed Kand locked When the dispenser of the invention is delivered to the ultimate consumer, it will in most instances be applied to the container ofv liquid to be dispensed thereby with the plunger either in its fully-depressed position, as in FIG- URE 2, or in its fully-projected position, as in FIGURE 1. In either event, suitable shipping seals will have been established and maintainedfor preventing loss or leakage of the liquid both through the pump discharge passage of the plunger and between the plunger and cylinder walls.

Assuming that the dispenser is delivered with the plunger locked in its fully-depressed position, as in FIGURE 2, the discharge of liquid through the internal pump passages will have been barred by successive internal seals. To this end, it will be seen that the inlet valve cone 24 is thrust against its valve seat 21 around the inlet port 20 by the lower end of the plunger 25. Plunger passage 29, in turn, is sealed by frictional reception of the sealing plug portion 65 of the valve, while the sealing valve 60 carried at the upper end of the plunger stem is similarly in axially-thrusting sealing relation with the outlet valve port defined by the depending sleeve 62. The seats around the ports 61 and 2) respectively are elastically expanded by the cooperating conical valve portions a and 24 so that the elastic contracting tendency of these ports, acting on the conical surfaces 60a and 24 maintains a constant resilient thrusting and seating force on both valve portions 60a and 24 against their respective ports.

Thus, liquid normally is unable even to enter the pump chamber 30 through the inlet port 20 prior to the initial use of the pump. However, where, after its initial use, the pump plunger is again locked in its fully-depressed position, any liquid then contained Within the chamber 30 is barred from entry into the lower end of the plunger by means of the sealing plug 65. Also, upward movement of liquid through the plunger is barred by the seated relation of the valve portion 60a in port 61.

In addition to the internal seals thus established in the fully-depressed position of the plunger, the enlargement or upper valve portion 72 of the plunger is at this time received within the stop ring 38 to resiliently compress the said stop ring radially between the opposed faces of the enlargement 72 and the bottom of groove 39. Thus, any liquid which may have entered the cylinder through the vent 69 or have leaked upwardly past the plunger skirt or piston 28, will be confined against escape past the sealing ring 38 which thus coacts with the plunger and pump cylinder to define an effective external seal.

Pumping action When the plunger and plunger head are rotated to release the threads 55 from the internally-threaded collal 12 of the plunger cylinder, the plunger spring 31 immediately expands to project the plunger upwardly and outwardly on its suction stroke. At the inception of the suction stroke, the frictional coupling provided by the interengaged plug portion 65 of the inlet valve and the plunger exerts a positive unseating force on the inlet valve to free the latter in the event it should have become stuck in place. This function is augmented by the resiliently-contracting tendency of the expanded valve seat 21. Similarly, the somewhat expanded valve seat of the port 61 and the sealing valve 60a cooperate in a manner to free themselves. As the inlet valve reaches the limit of its unseating movement, as determined by axial abutment of its disclike portion 30 with the lower coil of spring 31, continued upward movement of the plunger disengages it from the plug 65 while simultaneously unseating the valve portion 60a from port 61. Thereafter, continued upward movement of the plunger, with the inlet valve 23 unseated, causes liquid to be drawn upwardly through the dip tube 22 from the container and through the inlet port 20 into the pump chamber 30.

Moreover, in this upward or suction stroke of the plunger, the reduced diameter plunger portion 71 moves freely and with clearance through the sealing ring 38, during which time air from the atmosphere is free to seep downwardly between the ring and the open end of the pump cylinder and thence into the container through the vent 69 to replace liquid withdrawn by the pumping action.

Throughout the upward or suction stroke of the plunger, the upper pump valve 48 will normally be seated to produce a relatively-reduced pressure or suction within the pump chamber 30; or if the ball valve 48 is omitted, the discharge orifice 45 may be proportioned to produce a similar though less efficient function.

The upward unseating movement lof the inlet Valve 23 will have been arrested by the plunger spring, during the early portion of the suction stroke.

As the plunger nears the upper end or limit of its suction stroke, the sealing valve 16, being restrained against upward movement by its connection to the inlet valve, will be frictionally received and seated in sealing relation within the constricted port 59 of the plunger, as shown in FIGURE l. The suction st-roke of the plunger will then be terminated by abutment between the plunger stop ledge or shoulder 37 and the Vsealing ring 38. At this time, pump chamber 30 communicates freely with the container through the inlet port and tube 22, but the plunger passage is firmly sealed by seating of the valve 60 in port 59 of the plunger. At this time, an external seal is provided by the interengaged plunger ledge 37 and sealing ring 38 by virtue both of the axial sealing engagement aforementioned, as well :as of the radial sealing engagement of the plunger enlargement 73 Within the sealing ring.

Thus, the plunger cooperates with the sealing ring in the manner of a slide valve to seal off the vent opening 78 from communication with the atmosphere in either the fully-projected or fully-depressed positions of the plunger, while permitting such communication during normal operation of the plunger.

On the inception of each downward or compression stroke of the 4plunger by finger pressure on the plunger head, the frictional gripping or clutching engagement between the plunger constriction or valve seat 59 and its associated sealing valve 60 transmits a frictional seating thrlust from the plunger to the inlet valve 23. When the inlet valve is seated and no longer free to move with the plunger, continued plunger movement will afford a .positive unseating of the sealing valve 60.

The -plunger may obviously be reciprocated repeatedly to eject the desired amount of liquid, following which it may either be left in its fully-projected position, under the action of the plunger spring 31, or, if desired, may be locked in its fully-depressed position, in the manner shown in FIGURE 2. In either event, it will be quite apparent that the actuation of the inlet valve 23 and its associated sealing valve 60 will occur independently of gravity, through the transmission of frictional seating and unsealing forces from the plunger. If it is desired to free the pump structure completely from the action of gravity, the ball valve 48 may be eliminated and its function taken over, for instance, by a sufficiently-constricted discharge orifice 45 ofthe plunger head or `by a spring-loaded valve. Also, the action of the sealing valve or plug 65 will similarly be controlled by the plunger position independently of gravity. Thus, the plunger will be effectively sealed internally in either its fully-projected or fully-depressed position and will be fully sealed externally by the coaction between the plunger rod and the sealing ring in the manner of a slide valve.

Having thus described my invention, I claim:

1. In a reciprocating liquid pump, including a pump cylinder having an inlet port through one axial end thereof, an inlet valve disposed in said cylinder for axial movement within pre-determined limits into and from seating relation with said inlet port, and a plunger disposed for axial movement within pre-determined limits in said cylinder on suction and compression strokes respectively away from and toward said inlet port, said plunger being provided with an axial discharge passage therethrough; the improvements comprising:

(A) a pair of relatively axially-spaced sealing valve seats within said plunger and around said passage, and respectively defining ports of smaller cross sectional area than the discharge passage;

(B) a substantially-rigid valve stem afiixed to said in- -let valve and extending axially therefrom into said passage for relative axial movement therein; and

(C) a sealing valve fixed to said valve stem within the passage for relative movement between said sealing valve seats and for alternate seating engagement with said sealing valve seats at opposite limits of the movement of the plunger.

2. In a reciprocating liquid pump as defined in claim 1, the further improvement comprising means for limiting the unseating lmovement of said inlet valve, the seating of said inlet valve determining the limit of its seating movement.

3. In a reciprocating liquid pump as defined in claim 1, the further improvement wherein said sealing valve seats are located relatively adjacent and remote from said inlet port respectively, the valve stem being disposed for free movement through the port defined by said relativelyadjacent valve seat, friction clutch means on said valve stem normally positioned for relative movement between said sealing valve seats and proportioned for axial reception in and frictional radial engagement with said relativly-adjacent valve seat at the limit of each suction stroke of the -plunger to transmit a yieldable axial seating force from the plunger of the inlet valve on the inception of each compression stroke of the plunger.

4. The combination defined in claim 3, in which said friction clutch means comprises the sealing valve, said sealing valve being proportioned for seating and sealing radially against the inner periphery of said adjacent sealing valve seat while frictionally engaging same.

5. The combination defined in claim 4, in which said relatively-adjacent sealing valve seat is defined by oppositely-directed generally-conical surfaces diverging toward each other to define a port the inner periphery of which is proportioned for frictional sealing engagement with said sealing valve.

6. The combination defined in claim 4, in which said relatively-remote sealing valve seat is positioned for positive axial thrusting engagement with said sealing valve to transmit a positive seating force through said sealing valve and said valve stem to the inlet valve as the plunger approaches the limit of its movement toward the inlet valve, and means for releasably interlocking said plunger to said cylinder to secure the plunger at the said lastmentioned limit of its movement.

7. The combination defined in claim 6, in which said relatively-remote sealing valve seat is directed axially toward said sealing valve for positive seating abutment therewith.

8. In a reciprocating liquid pump as defined in claim 1, the further improvement in accordance with which said sealing valve is proportioned for axial movement completely through one of said sealing valve seats to facilitate assembly of the sealing valve and plunger, and for sealing and frictional engagement with the inner periphery of said one sealing valve seat during its passage therethrough.

9. In a liquid dispensing pump as defined in claim 1, the further improvement in which said plunger includes a third downwardly-directed annular sealing valve seat, a second sealing valve being carried by said valve stem in position to seat against said third sealing valve seat near the limit of the compression stroke of the plunger.

10. In a liquid dispensing pump as deiined in claim 1, the further feature in which said inlet valve comprises a plug directed axially toward said plunger and positioned for snug liquit-tight reception in said lplunger discharge passage near the limit of the compression stroke of said plunger.

11. In a liquid dispensing pump as dened in claim 10, the further improvement in which said sealing plug is frictionally received in said plunger discharge passage to transmit a yielding rictional unseating force from the plunger to the inlet valve on retraction of the plunger from its position at the limit of its movement toward the v inlet port.

12. In a reciprocating liquid pump as defined in claim 11, the further improvement in accordance with which said inlet port and said relatively-remote sealing seat are defined by yradially expansible annular means, said inlet valve and said sealing valve having conical portions for simultaneous sealing reception in the said inlet port and relatively-remote sealing seat, whereby the elastic contacting tendency of the respectively-annular means will maintain a constant resilient seating thrust of said annular means against the respective conical portions.

13. A fluid dispensing pump as defined in claim 1, in which said cylinder is encircled internally with a radial groove adjacent its axial end remote from said inlet port and is open through said axial end, said plunger including an annular stop shoulder directed toward said open end, said cylinder being formed with a vent opening through its side wall on the side of said groove remote from the open end, an annular plunger stop and sealing ring received in said groove and encircling said plunger, said ring being resistant to axial compression for axial sealing abutment with said plunger shoulder and with one axial end of the groove to limit the plunger movement away from said inlet port, said plunger having a portion of reduced diameter positioned for movement through said element to permit flow of fluid between said plunger and said ring during the major -portion of its stroke, and portions of relatively-larger diameter at opposite axial ends of said reduced diameter portion for sealing reception in said ring at the opposite limits of the plunger movement.

14. A fluid dispensing pump as deined in claim 13, in which said ring is resiliently compressible radially between said plunger and said cylinder.

15. In a reciprocating liquid pump, including a pum-p cylinder having an inlet port through one axial end thereof, an inlet valve disposed in said cylinder for axial movement within pre-determined limits into and from seating relation with said inlet port, and a plunger disposed for axial movement within pre-determined limits in said cylinder on suction and compression strokes respectively away from and toward said inlet port, said plunger being provided with an axial discharge passage therethrough; the improvements comprising:

(A) a pair of relatively axially spaced sealing valve seats in said plunger along said passage;

(B) and a sealing Valve supported from said inlet valve within said passage for alternate seating engagement with said sealing valve seats at opposite limits of the movement of the plunger.

16. In a reciprocating liquid pump as dened in claim 15, the improvement in accordance with which said sealing valve includes a plug proportion for functional sealing reception in said discharge passage.

References Cited UNITED STATES PATENTS 3,228,347 1/1966 Corsette ..103-178 FOREIGN PATENTS 9,599 5/1907 Denmark.

HENRY F. RADUAZO, Primary Examiner.

Claims (1)

1. IN A RECIPROCATING LIQUID PUMP, INCLUDING A PUMP CYLINDER HAVING AN INLET PORT THROUGH ONE AXIAL END THEREOF, AN INLET VALVE DISPOSED IN SAID CYLINDER FOR AXIAL MOVEMENT WITHIN PRE-DETERMINED LIMITS INTO AND FROM SEATING RELATION WITH SAID INLET PORT, AND A PLUNGER DISPOSED FOR AXIAL MOVEMENT WITHIN PRE-DETERMINED LIMITS IN SAID CYLINDER ON SUCTION AND COMPRESSION STROKES RESPECTIVELY AWAY FROM AND TOWARD SAID INLET PORT, SAID PLUNGER BEING PROVIDED WITH AN AXIAL DISCHARGE PASSAGE THERETHROUGH; THE IMPROVEMENTS COMPRISING: (A) A PAIR OF RELATIVELY AXIALLY-SPACED SEALING VALVE SEATS WITHIN SAID PLUNGER AND AROUND SAID PASSAGE, AND RESPECTIVELY DEFINING PORTS OF SMALLER CROSS SECTIONAL AREA THAN THE DISCHARGE PASSAGE; (B) A SUBSTANTIALLY-RIGID VALVE STEM AFFIXED TO SAID INLET VALVE AND EXTENDING AXIALLY THEREFROM INTO SAID PASSAGE FOR RELATIVE AXIAL MOVEMENT THEREIN; AND (C) A SEALING VALVE FIXED TO SAID VALVE STEM WITHIN THE PASSAGE FOR RELATIVE MOVEMENT BETWEEN SAID SEALING VALVE SEATS AND FOR ALTERNATE SEATING ENGAGEMENT WITH SAID SEALING VALVE SEATS AT OPPOSITE LIMITS OF THE MOVEMENT OF THE PLUNGER.

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