CA1057714A - Antidrip volumetric rapid filling machine - Google Patents

Abstract

A B S T R A C T

This device for rapid and extremely accurate filing of bottles includes a volumetric bi-acting piston, a submersible filling nozzle which opens only when it is actually dispensing and which carries an antidrip suction mechanism adapted to draw off only air above the fluid level when it is not picking up drips from the nozzle tip, provisions for control to avoid dis-pensing operations when no bottle is present in receiving position, and adjustability of volume and flow rate individually and volume in common for all filling heads in a multiple-head system -- all without stopping the filler. Also included are provisions for preventing entrainment of air in the system, and for removing any air which is originally trapped in the system at startup or through operation of a supply pump.

Description

This invention relates to an apparatus for at least partially filling containers, such as bottles, with flowable substances ranging from very viscous to very thin and including substances which readily form suds or foam~
According to the invention there is provided an appsratus for at least partially filling containers with flowable substance from a source thereof, having a dispensing system comprising: a volumetric metering chamber adapted to be connected to receive a flowable substance from a source thereof, and within the chamber a biacting piston arranged for motion between positive stops, for establishing controlled volumes of such substance;

` 1~)5 ~ ;i4 dispensing means, downstream of the chamber, for discharge of such controlled volumes into a con-tainer in a filling position along a discharge path terminating at a nozzle from which flowable substance can pass directly into a container without passing along any intervening conduit;
first means, in addition to hermetic sealing, for preventing or reducing access to the chamber of ambient air and/or of gas into the system and second means for preventing or reducing access of ambient air into the discharge path along substantially its whole length.
Through advantageous combination and coordination of certain principles and features heretofore known and employed in distinct and disparate segments of the filling-machine art, and heretofore thought incompatible by many practitioners of this art, it has been found to be possible to achieve a combination of high filling speed and remarkably fine volumetric precision and accuracy heretofore considered unfeasible.
The principles referred to are as follows:
(1~ Accurate fill requires a cyclically operating volumetric metering device.

(2) Accurate fill requires close control of liquid at all points in the system downstream from the metering device to prevent loss of liquid to the surrounds or otherwise -- so that all liquid metered actually enters and remains in the bottle, and no unmetered liquid enters the bottle.

(3) Accurate fill requires close control for and accounting of air which is or might be in the systeJn, as such air affects the fill to S7'714 the extent of the volume displaced. In some cases such trapped air may be gradually removed in successive fills; in other cases a bubble may remain trapped, expanding and contracting variably during the filling cycles; in either event objectionable im-precision of fill results. Leakage of the air into the system must be prevented or at least reduced, and air normally present in the system at startup, or injected into the system unavoidably as by the "whip-ing" action of some sorts of supply pumps and likedevices, or by cavitation, should preferably be sys-tematically removed.
(4~ Accurate fill requires close monitoring of system operation to guard against the possibility of bottles leaving the filler with only a partial fill due to incomplete cycling of the volumetric device (5) Accurate fill in a multiple-head filling machine requires that all the heads be operated under as nearly as possible iden-tical conditions of flow rate as well as nominal volume setting. Otherwise small differences in pres-sure drop through the dispensing lines can cause slightly different behavior of the fluid at and leaving the dispensing nozæle, and at other places in the system, thus rendering the fill imprecise due to the inter-head effects.
(~) Accurate fill requires that the operation generally be clean, in the sense that normal function of the filler should not deposit fluid on external surfaces of the bottle or the filling machine itself --even if there be quite reproducible or consistent ~t~S'77~4 in volume lost from the fill. Such external deposits even if reproducible have the effect of masking or concealing malfunctions of the apparatus -- and thereby prolonging the duration of such malfunctions until they become relatively more significant.
The implementation of these six principles in the present invention is described in ~eneral terms in the following paragraphs.
While these principles taken individually are recognized in various portions of the filling-machine art, as shown below their proper coordination and cooperation has never previously been efected.
In the present invention the volumetric device is a bi-ac~ing piston operating in a chamber. By "bi-acting piston" is meant a piston which meters fluid to the dispensing nozzle in both directions or strokes of its complete metering cycle.
Close liquid control in the present invention may be obtained by (a) employing a submersible dis-pensing nozzle, which fills deep within the bottle sothat sudsing or foaming of liquids subject to such tendency upon impact with the bottom of the bottle from a considerable height is minimized and by (b) fitting the dispensing nozzle with a tip-closure device which prevents uncontrolled discharge of fluid from the nozzle when the piston is not actually in motion, so that fluid intended for one bottle does not end up in the previous or next bottle; and by (c) further fitting the dispensing nozzle with a suitable mechanism for picking up drops of fluid from the tip of the nozzle as it is withdrawn from the container after filling, to avoid thefie drops dripping into the con-_ ~, _ i ` " 1057'7~4 tainer and thereby changing the fill, and also toavoid their dripping onto the outside of the con-tainer or onto the filling machine itself.
As used hexein, the term "submersible nozzle"
denotes one which (a) can be inserted into a container so that the dispensing orifice is below the final level of liquid in the container, and which (b) is made of materials which maintain structural integrity and parts which maintain functional operability when im-mersed in the dispensed substance (to the intendeddepth and in the intended manner).
Close control of air in the present invention may be obtained in part by advantageous combination of some features already described -- viz. (a) the use of a bi-acting piston to avoid sucking air into the volumetric chamber on the fluid-intake stroke, as happens with a single-acting piston; and (b) the use of a tip-closable dispensing nozzle, which prevents uncontrolled admission of air to the system through the nozzle while preventing uncontrolled release of fluid. Air control may further be effected by (c) interaction between the bi-acting piston and the closable nozzle, the latter permitting positive-pressurized operation of the entire system at. all times, to avoid sucking air into the volumetric chamber or other portions of the system across auxiliary or secondary seals -- such as, for example, at a seal between the volumetric chamber and a plunger attached to the piston and extending through an end ~all of the chamber for purposes of providing an e~ternal indication of piston position, and at other seals such as gaskets, hose connections and ~S77~4 the like; (d) suitable isolation of the fluid-trans-ferring tubulations, ducts and chambers from the tubulations of any pneumatic control system -- par-ticularly if at high pressure -- employed to monitor or direct system functions; (e) relative positioning of the dispensing nozzle above the volumetric chamber, so that air initially in the lines therebetween, and particularly within volumetric metering chambers, at startup tends to be eliminated promptly through its own buoyancy; (f) shaping and orientation of the piston and chamber, which has a plurality of ports, preferably two ports, so as to force any air bubbles out of the chamber promptly upon startup; and (g) pro-vision of an entrapment device upstream of the volu-metric chamber, to collect and remove any air initiallypresent in the fluid supply or "whipped" into the fluid supply as by centrifugal pumps -- or bubbles of air or fluid vapor produced by cavitation.
Close monitoring of system operation in the in-stant invention may be effected by providing an ex-tension of the piston through the volumetric chamber wall, and using the motion of this extension outside the chamber for monitoring and control of the system-function sequence. In particular (a) this extension, or "piston rod", or "plunger", is made to operate suitable sensors -- e.g., mechanical, magnetic, pneumatic, electrical -- to determine whether and when the piston completes its stroke before initiating a stroke in the opposite direction, and in particular ~1hether and when the piston completes a full volu-metric cycle, to give a full fill for an individual bottle, before initiating the next volumetric cycle;

~577~4 moreover (b) appropriate system functions are inter-locked with the above-mentioned sensors to alert the human operator to such incomplete cycling, and/or to hold system operation at least for the affected head until corrective action can he taken manually to pre-vent an incompletely-filled bottle from leaving the filler in the production line, and/or automatically to effect such corrective action.
Operation of all he~ads in a multiple-head fill-ing machine under substantially identical conditions of nominal volume setting and flow rate is implemented by providing (a) individual volume adjustment for each head -- this being conveniently effected, for example, by adjust-ing the distance between the stops which define the arrival of the external end of the plunger at the ex-tremes of its motion, because the volume dispensed is directly proportional to the "throw" of the piston at each stroke -- and (b) individual flow-rate adjust-ment for each head -- this being conveniently and stablely effected by providing in the apparatus a se-lectable plurality of constrictions or orifices of different size for insertion in the flow path to each dispensing nozzle -- and (c) common volume ad-justment for all units in a multiple-head fil.ling machine -- whereby the individual volumes once equal-ized can be all varied together over small excursions to obtain exactly the correct volume required (and whereby also, by operation of the common adjustment through larger excursions, the above advantages can be obtained with a single multiple-head filling machine for filling bottles of greatly different siæe, as for example one pint to five gallons).

~)S~7~4 Clean operation in the present invention may be obtained by (a) provision of a suction-operative drop-catching mechanism at the nozzle, which is care-fully synchronized with system sequencing so that it does not suck fluid up from the body of fluid in the bottle but only sucks drops -- potentially drips -- from the tip of the nozzle, well above the fluid level in the bottle, after filling; and (b) provision of inter-locks preventing system sequencing, and/or actual dis-charge of fluid from the dispensing nozzle, in theevent that no container is fed into receiving position under that particular nozzle. These provisions in turn interact with the positive pressurization men-tioned above as important for air control, in that a leaking seal anywhere in the system will produce an external deposit which can be seen -- since the bottles and system in normal, proper operation are clean -- thereby flagging the existence of the leak even when it amounts to only one of two drops per bottle.

BACKGROUND OF THE INVENTION

While some of the above points taken individu-~5 ally and cursorily may seem apparent, and while the filling-machine art and industry have stood severely in need of a machine which is both extremely rapid and extremely accurate -- since, in particular, the users of filling machines labor under consider-able economic disadvantage from the unavailabilityof such machines -- it nonetheless remains true that the above principles have never heretofore been co-operatively combined and coordinated in the ways and for the purposes herein described. I

lOS~
As a direct consequence the current state of the filling-machine art considers imprecisions of one or one-and-a-half ounce per gallon -- or 0.8 to 1.2%
-- to be at the limit of feasible operation, in a reasonably rapid filler. Since packaging companies must under the law fill every container with at least as much fluid as is nominally contained -- i.e., as the label indicates -- this means that the average container must be overfilled by at least 0.5 to 0.75 ounces per gallon, or 0.4 to 0.6%. Needless to say, 0.4~ of the value of product dispensed by a large manufacturer of liquid detergent, or antifreeze, or solvent, amounts to a significant sum -- particularly in low-profit-margin industries, where 0.4% of the gross value may represent 20% of the net profit.
Yet the requirement that every customer receive at least a nominal fill is properly founded in the currently maturing concern for consumer protection;
while the objectionability of significant overfill, in some industries, is compounded by the undesirability of waste per se from an ecological or natural-resources-conservation point of view.
By contrast the above-stated principles, skill-fully applied, permit manufacture of filling machines precise to 1/28 ounce, or roughly five drops, per gallon, or 0.03%. This precision is 30 times - well over an order of magnitude -- finer than that obtain-able with the best filling machines heretofore available.
Previous filling machines have employed sub-mersible nozzles, some with closable tips. ~owever, these have been employed primarily with bottom-filling valves for ~udsing liquids, in which the product is ~57~L4 transported into the container without measuring, and such fillers are subject to considerable inaccuracy both through the absence of an accurate volumetric system per se and also through the fact that any drip-catching mechanisms associated with such fillers have operated to draw off fluid below the fluid level in the bottle, thereby variably (i.e., imprecisely) diminishing the fill.
Other previous filling machines have employed volumetric pistons, but most of these have objection-ably been single-acting devices, wherein the piston is driven back and forth by a mechanical cam or like mechanism, only sucking product into the cylinder at one stroke and only driving it from the cylinder in the following stroke. I have found experimentally that tiny bubbles are entrained at the piston-chamber seal during the suction stroke, in such fillers, and on the expulsion stroke some of the bubbles are carried with the fluid to the dispensing nozzle, or as earlier noted remain trapped and are subject to variable expansion and contraction, in either event variably and objectionably diminishing the volume of fluid dispensed.
Some previous filling machines have employed bi-acting volumetric pistons -- e.g., Buford, U.S. 3,447,281;
and British patent specification 807.338 to Unilever Limited; and U.S. patents 3,419,053 to Tanner; and 2,276,157 and 2,303,822 to Chapman. A bi-acting piston is disclosed by E.A. Pontifex in U.S. 162,575. In the Unilever Patent Specification, however, the piston is a dual element having an air space between its t~o pressuring sidefi and thus failing to obviate the air-entrainment disadvantages of the single-acting piston.

~57~4 In this regard it is important to emphasize that for the fullest realization of the advantages of the instant invention all of the aforementioned principles must be brought into action, through suitable imple-mentations such as the features herein described.That is, as these principles are functionally com-bined in concert the resulting incremental capability, with the addition of each principle, becomes quali-tatively different -- where by qualitatively differ-ent we here mean an accuracy improvement by consider-ably better than an order of magnitude in a clean, very fast filling machine, resulting in the ~ualita-tively different capacity of accurately filling each and every container to at least its nominal volume and with negligible overfill.
Of course it is possible to omit some of these principles and suffer the loss of this qualitative difference in capability only under extraordinary conditions: for example, omission of suitable sequence-control provisions may not prevent manufactureof a filling machine which is extremely accurate -- ex-cept in the event of certain kinds of system malfunc-tion such as incomplete cycling of the ~olumetric piston or failure of the bottle-feed mechanism. Hence some of these features may be re-garded as secondary, and their omission from a par-ticular device shall not diminish the applicability to such device of those of the appended claims which do not recite such secondary features.
There will no~7 be described, by way of example only, various forms of the apparatus in accordance with the invention, and parts of the apparatus, with refer~nce to the accompanying drawings in which:

1~)57714 DESCRIPTION OF T~ DR~WINGS

Figs. la, lb and lc are drawings in section show-ing the configuration of the submersible closable nozzle and the relative positions of its parts at three different positions relative to a hottle to be filled -- these corresponding to five different phases of the operational sequence.
Figs. 2 and 2a through 2e are drawings mostly in section and partly in elevation showing the con-figuration of the various parts, and the interconnec-tions of these parts, forming one embodiment of the present invention, specifically one in which pneumatic valves are employed as sensors and are employed to control system sequencing. These illustrations repre-sent the operation of a "single-head" system, that is, a system having only one piston and one nozzle for filling one bottle at a time; these illustrations also represent one head of a multiple-head system, that is, a system having a multiplicity of pistons each with its respective nozzle and sharing a common supply and certain other common elements for filling a multi-plicity of bottles concurrently or even simultaneously Figs. 2a through 2d, in particular, represent equivalent arrangements for connection of one of the modules in Fig. 2 to the other components of the Fig. 2 system. Also, Fig. 2e in particular represents the interior of that same module, partly cut away as Fig. 2, but in Fig. 2e a certain movable internal part of that module is shown in a different position than that in which it is shown in Fig. 2.
Fig. 3 is an elevation drawing, partly cut away, ~howing portions of a rotary multiple-head filling 1~57714 machine in accordance with the instant invention.
~Jhile an actual device of this sort may have as many as a dozen or twenty or even more heads, for purposes of clarity only three heads are illustrated in Fig. 3.
It may be noted in this connection that the vertical orientation of the metering pistons and chambers arises from space limitations in multiple-head filling machines. The embodiment of Fig. 3 is sub-stantially in correspondence with that of Fig. 2 and 2a except that the sequence-monitoring and -controlling sensors are electrical rather than pneumatic.
Fig. 3a is an electrical schematic represent-ing the electrical wiring to the elements forming each "head", and its corresponding peripheral devices, of Fig. 3.
Fig. 4 is an elevation drawing showing portions of a rotary multiple-head filling machine in accord-ance with the instant invention. This embodiment is as to hardware very similar to that of Fig. 3, and accordingly only one and part of a second head are shown; it is different from the embodiment of Fig. 3 in that pneumatic rather than electrical sequence sensing and control are employed, as in Fig. 2; and also in that the sequence-control logic is somewhat different, as hereinafter described.
Fig. 4a is a pneumatic schematic, with some de-vices shown in section, representing pneumatic tubula-tion connections of the elements forming each "head", and its corresponding peripheral devices, of Fig. 4.
Fig. 4b is an elevation drawing showing certain variations in the design of a directional-control fluid valve employed in the various embodiments.

1~357714 Fig. 5 is a pneumatic schematic representing con-nections for sequence sensing and control of a rec-tangular-array multiple-head filling machine in ac-cordance with the instant invention, and intended for substantially simultaneous filling of containers in a "case-at-a-time" or "in-line" ("line-at-a-time") mode.

DESCRIPTION OF EMBODI~NTS

As shown in Figs. la and lc, the submersible closable nozzle assembly comprises three basic parts:
(1) a subassembly 1 consisting of a supply body la and attached rotably thereinto a supply hood lb with lateral orifices lk and lj and integrally attached centerpin lc and tip ld; the supply body la also having a lateral supply tubulation lg;
(2) a supply sleeve 2;
(3) a vacuum hood 3 with depending section 3b, downward-extending actuator step 3a, and lateral vacuum tubulation 3c.
There are in addition five O-ring (or T-ring) seals 7, 8, 9 and 10, and two springs 5 and 6. The en-tire assembly is suspended from a lowerable support staff lh -- indicated as a rod extending upward out of the drawings -- which is integral with the supply body la.
The apparatus is essentially a figure of revolu-tion -- i.e., cylindrical or conical -- except for the lateral tubulations lg and 3c, the lateral orifices lk and lj, the transverse passage lf in the tip ld, the "actuator" section 3a which forms part of the right side of the vacuum hood 3, and the springs 5 and 6.

16~S7714 Lateral dimensions are greatly exaggerated re-lated to vertical dimensions, for the sake of clarity.
In Fig. la the apparatus appears suspended above a container 4, such as a bottle, which is to be auto-matically filled using the apparatus.
Note that in Fig. la the vacuum hood 3 and supply sleeve 2 are both in contact with seals 9 and 10 mounted in the tip ld. Thus the material supply -- ~enerally liquid or syrup -- is constrained within the cavity formed by the supply body la, supply hood lb, and tip ld; while the vacuum system sucks air through a drip-catching orifice at the end of passage le from the vicinity of the bottom of tip ld, via tubulation 3c and the pas-sages lf and le within the tip. As shown, neither spring is compressed beyond the amount required to effect good seal closures at seals 9 and 10.
If Fig. la is taken to be a view of the nozzle assembly descending into position to start filling the bottle, then of course there is no liquid in the bottle; hence eventual liquid level lla is shown here in the phantom line. In this state, the sucking opera-tion through the drip-catching orifice is not accom-plishing any useful purpose -- but it is normally left in operation for simplicity of the control system.
~s the assembly is lowered further, the actuator portion 3a of the vacuum hood 3 contacts the top of the bottle 4, preventing further descent of the vacuum hood. The rest of the assembly continues to move down, compressing the springs -~ primarily the lighter spring 6. The supply sleeve 2 slides through the seal 8 mounted inside the vacuum hood, so that the supply sleeve, the centerpin and the tip continue downward to the position shown in Fig. lb. The lower 1~5'77~4 seal 10 mounted on the tip ld is now lowered out of contact with the vacuum hood 3, so the vacuum system is now sucking air from the region above the tip through a second orifice. The supply sleeve 2, however, is still maintaining contact with its tip seal 9, so there is still no supply flow and no fluid in the bottle.
As the supply body an~ hood, centerpin and tip --subassembly 1 -- continue to move downward, the lighter spring 6 is fully compressed, between the vacuum hood 3 and the flange 2a of the supply sleeve 2, stopping descent of the supply sleeve. The supply body, hood, centerpin and tip, however, move still further -- lowering the upper seal 9 on the tip out of contact with the supply sleeve 2 -- to the position shown in Fig. lc.
This permits supply flow, and the bottle is filled.
Filling is expedited -- though under some typical con-ditions this effect is negligible -- by removal of air from the bottle by the vacuum system; air is also pushed out of the mouth of the bottle by the rising fluid. At the lowest point of descent of the supply body, hood and attached centerpin and tip, the inside of the hood may contact the top of the supply sleeve --depending on equipment design. The fluid rises above the bottom of the supply sleeve, to the level lla shown in Fig. lc.
~ 7hen the rated fluid volume has been transferred to the bottle, the supply body and attached parts rise again. At the position of Fig. lb, with the tip ld and the bottom of the supply sleeve 2 still immersed, the supply channel is again closed. This prevents spillage of uncontrolled quantities of fluid from within the sleeve, between fills, either into a container or otherwise.

`` 10577~4 The assembly rises toward the position of Fig. la, where the vacuum system sucks fluid drops from the tip, providing a clean fill.
Flow-rate adjustment is implemented by providing a plurality of orifices such as lj and lk arrayed about the periphery of the upper portion of supply hood lb, each selectably positionable for communication with supply tubulation lg by means of rotation of hood lb with respect to supply body la. Suitable detent means (not illustrated) are provided to maintain the hood lb in the angular position thus selected.
The apparatus may take forms considerably differ-ent from that illustrated, but the key features are (1) provision for supplying material to ~ill the con-tainer via a conduit whose lower end extends into thecontainer and is submerged by the fluid in the con-tainer when the fill is complete; (2) closing of the fill conduit at its very tip before the nozzle is removed from the fluid; (3) provision for vacuum removal of drips, after the nozzle is removed from the fluid, and (4) flow-rate adjustment. A secondary feature is (5) vacuum assist of air removal from the container during filling.
All of these characteristics are directed to pro-ducing a rapid but extremely accurate and clean fill.
The systems shown in the following illustrationsall include submersible filling nozzle assemblies per Figs. la through lc, though not shown in such detail.
Fig. 2 illustrates generally the subassembly 1, sleeve 2, vacuum hood 3 and attached parts, identi-fied as in Figs. la through lc. The fluid level in Fiy, 2 i5 ~hown at llb; thus the sequence in Fig. 2 has proceeded to the point at which the nozzle is in l~S77~4 the position of Fig. lc but the liquid level has not yet risen to the level lla therein indicated.
Raising and lowerin~ of the nozzle subassembly relative to the container is in principle effectable either by moving the container or moving the nozzle subassembly. Of these alternative and equivalent ways of operation only the latter is herein pictured. In Fig. 2 the subassembly is shown as controlled by air cylinder 35, under control of bidirectional pushbutton valve 36; supplying air from source 37 to cylinder 35 raises the subassembly, and interrupting the air connection permits the subassembly to descend under the influence of gravity. Valve 36 may be operated manually or pedally by forces at 36a and 36b, or may as appropriate be connected for actuation by mechan-ical cams or other means.
Vacuum connection via 3c is made to vacuum vessel 800, whose internal volume is suitably maintained at a negative pressure relative to ambient by a pump mechanism whose final delivery chamber is representable as vessel 800. Fixed to support staff lh is pushbutton valve 31, for use as described below.
Shown generally at 26 is a volumetric chamber defined by end walls 26a and 26g, side wall 26b, and other seals and porting as apparent. A piston is sho~m within the chamber at 27, with upper face 27a and advantageously with shaped lower face 27b and a shaped projection 27c adapted for interaction with the corres-ponding features of wall 26g as herebelow detailed.
The piston is also provided with extension 27e and remote actuating member 27f, and the piston and ex-tension are mounted for longitudinal sliding motion within and outside of the chamber while ~aintaining i - 1û -1~577~4 seals thereto at 25 and 24 -- thus forming first and second subchambers for fluid at lli above and llj below the piston.
~lso suitably mounted to chamber 26 as by brackets 28, 28a and 28b are pneumatic pushbutton valves 29 and 30, the latter being a single-channel valve and the former a dual-channel valve or t~o single-channel valves ganged together, or any other suitable func-tional equivalent. These valves are both adjustably positioned in the path of actuator 27f to "sense"
positioning thereof and thus of the piston 27 within the chamber; and in response to such "sensin~" to gen-erate, when suitably excited by attachment of pneu-matic tubulations 38d and 38c from compressed-air source 37, pneumatic signals to control system opera-tion as herebelow described. Actuated surfaces 30a and 29a of the valves 30 and 29 respectively are spring-loaded outwards and actuated by force from member 27f.
The amplitude of the piston excursion is thus positively but adjustably defined and thus the metered volumes of substance are substantially free of varia-tion due to any time delay in operation of the control system of the apparatus.
Flow of substance to be dispensed is to and from the chamber 26 via tubulations 12d and 12e and five-port, four-way valve 14. This valve in turn is connected via tubulation 12f and other intermediate devices as shown to supply tank 62 and via tuhulations 12b, 12c, and 12a, to the dispensing-nozzle supply subassemhly 1. Within valve 14 is movable spool 15, having three sections, 15b, 15d and 15f just slightly smaller in external diameter than the narrO~JeSt internal diameter of the main barrel of the valve, and slidably sealed thcreto as by seals - 19 ~

l~)S7714 17, 18, 19, l9a, 19b, 20, 21 and 22 for motion between two positions: one position as shown in Fig. 2 and the other position as shown in Fig. 2e.
The length of central spool section 15d must be such as to bridge seals 19 and l9a or seals 19 and 19b, to prevent improper bypassing during shiftin~ of the spool.
When spool 15 is in the position illustrated in Fig. 2, fluid at lln from the supply lls via the inter-mediate tubulations and devices shown passes into subchamber llm within the valve barrel formed by the end walls of spool sections 15f and 15d and the outer cylindrical wall of necked-down intermediate portion 15e, and from this subchamber flows as at llk into lS the first (lower) subchamber of chamber 26, holding fluid llj. This fluid forces piston 27 upward by pressure at the lower surfaces 27b, 27c and 27d of the piston, whose upper surface 27a forces fluid lli in the second (upper) subchamber correspondingly up-ward and out as at llh into valve subchamber llg formed by the end walls of spool sections 15b and 15d and the outer cylindrical wall of necked-down intermediate portion 15c. From this subchamber the fluid proceeds as at lle and lld to the dispensing nozzle subassembly 1. Once filling has begun, the "CONTAINER READY" cam 32 must be manually or automatically withdrawn from contact with bu~ton 31a, as will be seen shortly.
During this operation, fluid is discharged at llc into the bottle 4, and the actuator 27f rises toward button 30a. When the actuator fully depresses the "OUT" valve button 30a, the piston is mechanically halted thereby, and compressed air from line 38c proceeds via line 38f and hole 14a in the side lQ57714 wall of the four-way valve into contact ~lith the end wall of spool section 15b, and the air pressure thereon forces the spool to the position shown in Fig. 2e.
Connections are thereby reversed so that enter-ing fluid lln flows via llh to lli, forcing piston 27 downward and thereby forcing fluid at llj from below the piston outward as at llk, whence it traverses the valve and exits at llf to lld, where as before it reaches and is dispensed through nozzle subassembly 1 and sleeve 2.
This operation continues until the piston bottoms out. Although actuator 27f does fully depress button 29a of the "IN" valve 29, no control action results therefrom yet, because due to withdrawal of cam 32 the valve 29 is not pneumatically excited via valve 31.
The dispensing nozzle is then raised from the container as by force at surface 36a of valve 36, to actuate air cylinder 35; the full bottle is re-moved and an empty one positioned in its place.
Surface 36b is depressed to deactivate the air cylinder 35 and permit lowering of the nozzle.
After the vacuum hood 3 has had ample time to descend into contact with the top of bottle 4, the cam 32 is replaced in the location shown in the figure.
If the placement of a bottle in receiving position as shown has not been accomplished, then the nozzle has proceeded past the height illustrated and the button 31 is not in position to be depressed by the cam 32, so no cycle-control action results. The same is the case in the event the nozzle fails to descend fully to engage the ~ottle.

15)577~4 However, if the bottle is properly in place then repositioning of cam 32 as illustrated provides pneu-matic signal from source 37 via 38a, 38b and 38d to excite pneumatic sensor valve 29. ~s the latter has, S per the normal operational cycle above described, al-ready been actuated, pneumatic signals are applied ther~through and via line 38e to hole 14b at the right (as illustrated) end of valve 14, to force the spool back to the position shown in Fig, 2. This ini-tiates another filling cycle as above described, pro-vided that the spool responds properly.
If the spool does not move in response to the pneumatic signal from valve 29, the cycle will not start. This can generally be the case -- barring seri-ous breakdown -- only when the system has been shut down for a period of many hours, permitting the com-pliant seals 17, 18, 19, 19a, l9b, 20 21 and 22 to "cold-flow" into the pores of the spool sections 15b, 15d and lSf. Breaking the spool loose under these con-ditions may require a force ten times the normal oper-ating force applied to shift the spool back and forth.
To ascertain whether this has occurred, external ex-tensions 15a and 15g are provided for the spool and these are slidably sealed at 16 and 23 to the internal circumferences of apertures in the end walls. When the system is to be turned on after being shut down for several days, the operator first manually de-presses buttons 31a and 29a, or button 30a as appro-priate, while visually or otherwise observing the ex-tensions 15a and 15g to verify that the spool is not"frozen" in place: when this verification can be satisfactorily completed, the substance supply can be connected and operation begun. If the initial veri-~ ~2 -i()57~4 fication attempt is negative, the operator can tap on an end anvil 15i or lSh to free the spool, and then repeat the test; of course the "tap" can be a force automatically applied through a cam or otherwise.
In the event that the nozzle is raised out of contact with the bottle, thereby sealing sleeve 2 to tip ld, before the piston has had time to bottom out, then when the next bottle is in position and the nozzle lowered to contact the bottle and with it valve 38b, even if the nozzle stops at the correct height to en-gage cam 32 and excite valve 29 no pneumatic signal will pass through line 38e to shift the spool -- be-cause the button 29a has not been depressed by actu-ator 27f. This is essential to avoid passage of the previous (underfilled) bottle into production line and marketing, and to avoid continued underfilling of the series of bottles to follow.
Under these circumstances the valve 29 instead generates an incomplete-cycle signal via line 38g to utilization means which may comprise (1) an alarm as represented by bell 39 and pneumatically-actuated clapper 38h, (2) pneumatically-actuated supply-fluid shutdown valve 33 with reset button 33a, (3) pneu-matically-actuated compressed-air shutdown valve 34 with reset button 34a and a time-delay provision com-prising constriction 38i and expansion charnber 38k to ensure supply shutdown prior to disabling of the pneu-matic system, or (4) interlocks (not shown) to remove the incompletely filled bottle from the production line. Depending on the details of system operation these shutdown provisions rnay or may not be useful in a given system.

105'~7~4 Some systems may be supplied with fluid for dis-pensin~ via tubulation 12f directly from supply lls in tank 42, by gravity. In other cases a pump 43 may be provided; in such cases, particularly in the event a centrifugal pump is employed which tends to "whip"
air bubbles into certain kinds of fluids, an air-entrapment device as indicated at 41 is desirable.
Container wall 41 defines a broadened flow path for fluid llo, relative to the breadth of other portions of the flow path as at llr and lln, so that the velo-city of fluid through container 41 is greatly diminished relative to that through tubulations elsewhere in the system, as 12g and 12f. The transverse dimensions and length of the container must be worked out in terms of the flow rates and viscosities for which the system is de-signed, so that air bubbles entering with fluid from the tubulation 12g have ample time to rise to the top of the container 41 of their own buoyancy before reaching the dome section 41a. Such bubbles thus ac-cumulate in the dome section 41a forming an air spaceabove the fluid level llp. As the fluid level llp falls by accumulation of additional bubbles the float 40 falls also and with it the attached needle of needle valve 40a, whereby air is exhausted through the escape needle valve 40a to maintain the fluid level llp above the bottom of the dome section 41a -- or in any event above the top of the exit tubulation 12f.
Another air-entrainment control feature i5 the cooperative shaping of piston 27 lower surface 27b and the projection 27c and its lower surface 27d with chamber lower end wall 26c, port 26d and the bottom 26h of port 26d, so as to expel from the chamber any air bubbles initially trapped in the system at startup.

~)5'~7~4 The effect is obtained in the embodiment shown by causing the clearance between surface 27b and surface 26c to be slightly larger at the center of the cham-ber than at its periphery, and causing the clearance between surfaces 27d and 26h to be slightly larger at the right side, which opens into the tubulation, than at the left (blind) side. That is, the inclination of the conical surface 27b to the diameter of the chamber is slightly less than the inclination of the conical surface 26c thereto, and similarly with conical surfaces 27c and 26d, and inclined planar surfaces 27d and 26h. Thus the periphery of the piston bottoms out to the periphery of the chamber end wall but the inner portions of the piston do not bottom out, thus forming a wedge-shaped space which squeezes bubbles toward the central port and down into the port and out through tubulation 12e.
Yet another air-entrainment control feature is provided in the form of double seals 17 and 18 in series, and 21 and 22 in series, with respective re-lief holes 14d and 14e to ambient pressure, whereby seal leaks cannot result in pneumatic air leakage in-to fill fluid (or vice versa) but only to the ambient air and surrounds.
To align the system for operation, the bracket 28b is adjusted to bring button 29a into its just-fully-depressed state when the piston 27 is fully bottomed out in the chamber. The bracket 28a is then adjusted so that button 30a is just fully depressed ~7hen the piston is raised to a position which dispenses through tube 12d half the desired fill volume -- ma -king appropriate allowance for the volume of the plunger within the chamber~ This adjustment may be i l~S7 71~
expedited in a variety of ways, such as the use of graduations along member 2~ or weighing the fluid dis-pensed into a container while the container is still in position under the nozzle. In any event small ad-justments will generally be required after the systemis in operation to obtain an exactly accurate fill.
Rotation of the supply hood 501b with respect to supply body 501a for the purpose of selecting ori-fices to regulate flow rate -- and correspondingly for each of the other heads on the filler, all as described with respect to orifices lk and lj of Figs. la, lb and lc -- is particularly important in all multiple-head systems, including that illustrated in Fig. 3, to equalize flow rates for the purposes set forth here-above under "Summary of the Invention".
Numerous other arrangements for connection ofthe valve 14 to chamber 26 and to supply tank 42 and nozzle subassembly 1 are equivalent in operation to that shown in Fig. 2. Some of these equivalents are 2G pictured in Figs. 2a through 2d. While the type of valve pictured in Figs. 2 and 2a through 2d is particularly well suited to use with a highly precise and rapid filling machine, other types of valving providing -- as does this type -- four flow paths, available in two combinations, are in principle equivalent and may be substituted as appropriate.
The hardware at each "head" of Fig. 3 is highly similar to that indicated in the system of Fig. 2.
One important difference is that the pneumatic sen-sors 29, 30 and 31 and the pneumatic spool-shi~ting provisions o Fig. 2 are here substituted for by electrical sensors 529, 530 and 531 and electrical 577~4 solenoids 570 and 569, for the head shown near the left-hand side of the figure; correspondingly numbered elements with the prefix "6" for the head shown near right-center, and correspondingly numbered elements with the prefix "7" for the head shown near the right side of the figure. Another difference is that the connections between the valves and supply nozzles have been shown somewhat more realistically in Fig. 3 as comprising flexible sections 512h, 712h to accom-modate nozzle vertical motion. Another important dif-ference is that the apparatus is here mounted and the bottles rest on a rotary platform 89, and all of the other elements of the apparatus similarly rotate with platform 89, through mechanical interconnections not illustrated -- with the exception of tank 42, hand-operated sprocket 53, bell 390, relay 56, motor-gearbox 57-58 and electrical attachments thereto and gear 59 driven thereby, pump 800, cams 43 and 66 and the various attachments thereto, all of which are stationary.
Wires to the various electrical components are connected as indicated schematically in Fig. 3a, to obtain substantially the same logical sequence-control functions as in Fig. 2, but here electrically. While connections for only one head are shown in Fig. 3a, these connections are duplicated for each of the other heads of Fig. 3. Connections from the rotating plat-form to the stationary elements of the apparatus are made via slip-contacts or "brushes" 931 for the "hot"
power line, 969 for the ground line, and 929 for the utilization means, here comprising a bell 390, and a relay 56 for interrupting power to drive motor 57 to stop rotation of the apparatus in event a "~ON-ln~7~7~4 TAINER READY" switch is actuated before an "IN" switch.
The "CONTAINER READY " switches here are actuated by cam 66, suspended by hinge 65 from stationary plate 62.
If desired to avoid the possibility of multiply over-filling a container in the event the rotary platformshould stop with one of the "CONTAINER READY" switches depressed by cam 66, solenoid 67 may be positioned by bracket 64 and operated in response to platform stop-page, by application of power via connections 63 to pull cam 66 out away from engagement position, and then by interruption of power via connections 63 to the solenoid to release the latter into engagement position subsequently when rotary motion resumes.
As shown in Fig. 3 the raising and lowering of the nozzles is effected by cam 43, shown partially cut away, which raises the nozzles by pushing on suit-ably mounted cam followers fixed to the support staffs of the nozzle subassemblies. Ilere the followers are shown as conveniently mounted just behind the switches, on the respective staffs.
As in Fig. 2 the switches 529, 530 and so forth are mounted for vertical adjustment, so as to permit alignment and volume calibration as earlier described.
Here however there is an added important feature in the mounting of all the "OUT" switches to a common plate 44, suspended by threaded rods 45 from the up-per rotating plate 60. The distance between platform 89 and plate 44 is controlled by adjusting the dis-tance between plates 44 and 60, and this in turn by adjusting the angular positions of the threaded rods 45.
The threaded rods in turn are rotated by sprock-ets 46, in turn operated by chain or belt ~1. The belt 61 i8 functionally connected by sprockets 49a, l~S~7~4 49, and 51, and belts 50 and 52, to sprocket wheel 53 and handle 54, stationarily mounted for rotation about the axis of wheel 53 as at 55. It will be appreciated that claarance must be provided between the sprocket 49a and the sprocket 46, for instance by mounting sproc~et 49a so as to engage the belt or chain above the level of the other sprockets. By this means common adjustment of the volumes dispensed at all the heads may be effected by manipulation of the handle 54 whether the platform and the rest of the machine are rotating or not. When the machine is in operation and rotating, the handle 54 is continually turned by the action of belt 61 upon sprocket 49a;
the handle may be momentarily manually stopped, or pushed forward momentarily in the same direction as its continual travel, to make a small adjustment in the height of plate 44 and thereby the volumes dis-pensed from all the heads in common.
Bottles are loaded onto the rotary platform 89 and unloaded therefrom near the right-hand end of the drawing, where as shown cam 43 causes the nozzles to be in raised position. The actuator as at 727f should in normal operation be fully down when the heads pass this point, and should be only just begin-ning to rise as at 627f for heads which have justpassed cam 66. The system operation for heads in the position shown with prefixes "5" in the callouts, near the left-hand side of the drawing, corresponds generally to the phase of operation represented in Fig. 2.
Suction lines 503c, 703c and so forth are con-nected by a conventional rotary joint to suction line 803c from the pump 800.

I

1~:)577~4 The system of Fig. 4, like that of Fig. 2, em-ploys pneumatic sensors and pneumatic actuation of the spool valve; it also employs pneumatic actuation via air cylinder 867 of cam 66. The elements of the head s shown near the left side of Fig. 4 correspond to those in Figs. 2 and 3 with the su~stitution of call-out prefixes "10"; and the elements of the head shown near the right side of Fig. 4 correspond similarly with the substitution of callout prefixes "11".
Valve 1038~ from the high-pressure air supply 37 to air cylinder 867 is operated to withdraw and re-lease cam 66 in response to rotary-operation stoppage and resumption as described above for the solenoid operating cam 66 with reference to Fig. 3.
However the system shown in Fig. 4 is different in the details of its sequence-control logic, by the addition of pneumatic "SYSTEM READY" pushbutton valves 1075, 1175, and so forth, mounted for rotation with the upper plate. These valves are actuated by engagement with cam 76, stationarily mounted as by bracket 76a, to test the status of the "IN" pushbuttons while the nozzles are out of the bottles, in advance of the engagement of cam 66 with pushbutton valves 1131, 1031, and so forth. If an "IN" pushbutton such as 1029 is not properly depressed when the correspond-ing "SYSTEM READY" pushbutton 1075 is actuated by cam 76, pneumatic signals pass to utilization means 938g for alarm and/or shutdown functions as previously de-scribed. By providing this "SYSTEM READY" button-cam combination as a separate entity from the "CONTAINER
READY" buttons and cam 66, some additional latitude is gained in the exact positioning of "CONTAIMER READY"

cam 66 angularly "ith respect to nozzle-raising cam 43 i~577~4 (Fig. 3). This can permit in some instances careful synchronization of the start of the piston cycle with respect to the opening of the nozzle; such careful synchronization is critical to avoid violent sudsing of some liquids on pressurized discharge from the nozzle.
Fig. 4b shows in one drawing various features which may be incorporated in the spool to provide external visibility of the position of the spool with-in the valve barrel. The external spool extensions as 1215g, shown in earlier drawings, are reproduced here for completeness. A section 1214h of the valve barrel may be constructed of transparent material to permit direct observation of the end 1215f of the spool. One of the isolation holes -- represented as 14d in Fig.
2 -- may be made large as at 1214i in Fig. 4b (with suitable separation of the isolation seals at the two sides thereof), exposing a portion of the spool wall 1215b and suitable indicia 1215h thereon. Again, these various features may be considered equivalent alterna-tives, any one of which may be employed, though some externally manipulable extension such as 1215g is in any event desirable to permit freeing of the spool by a manually applied blow or by automatic mechanical means.
Fig. 5 illustrates schematically the pneumatic connections for a case-at-a-time or in-line (line-at-a-time) filler. }~igh-pressure air from a suitable com-pressor or other source enters the system at 895, and traverses filter 894, pressure regulator 883 and oiler 893 which provides lubrication for the various pneumatic valves and other pneumatically operated components.
(These system elements 894, 883 and 893 may be present i¢~S-7714 in the other pneumatic systems hereinabove discussed.) The twelve pushbutton valves 884 in series are "IN"
sensors analogous in function to the lower section of valve 29 in Fig. 2, and the twelve pushbutton valves 887 connected in parallel to manifold 896 are "OUT"
sensors analogous to the valve 30 in Fig. 2.
Spool valve 888 is typical of twelve such valves connected between manifold 890 and the respective pushbuttons 887, and is analogous in function to spool valve 14 of Fig. 2.
Nozzles 886 are representative of twelve nozzles identical in function to the nozzle assembly of Figs. la, lb, lc and 2; these nozzles are raised and lowered in common by air cylinder 885, in response respectively to pneumatic signals at 885b and 885a respectively, applied from selector valve 884a which is in turn controlled pneumatically by signals at 898 and 899 from foot-pedal-actuated selector valve 891.
When pressurized air is applied through valve 884a to line 885b to raise the heads, this same line 885b also applied air to air motor 882 which operates vacuum pump 800a, fitted with muffler 876. The vacuum pump applies suction via manifold 878 to the various suction lines as 3c in Fig. 2, through separator bowl 879 which removes collected droplets from the suction path and deposits them via air-operated valve 880 in collector bottle 881. The air-operated valve also receives controlling air signals via 885b when the heads are raised (or rising); to close valve 880 to obtain maximum suction; and to open valve 880 when the heads are lowered, to permit collected droplets to pass into bot~le 881. (System elements 882, 876, 879, 880 and 881 may advantageously be present in certain of the other pneumatic systems hereinabove discufised.) 1~)577~4 To operate the system, with the heads initially all raised and the "IN" buttons 884 all depressed by their respective actuators (as 27f in Fig. 2), and with a case of empty bottles in receiving position under the he.ads, the operator first operates pedal-actuated valve 891 to apply pneumatic signal from 896 via 884 and 897 to line 898, which applies "pilot air"
to shift the spool in valve 884, applying high-volume air flow to air cylinder 885 via line 885a to lower the heads.
The operator then actuates start valve 892 to shift the spool in fluid-control valve 888, and the other eleven valves of which it is typical, starting upward the volumetric pistons (not shown) operated by spool valves 888. As soon as this happens the "IN" buttons 884 are closed by deactuation on the part of their respective actuators (such as 27f of Fig. 2), preventing any further effect on the system of manipulating foot-pedal selector valve 891, which may be released by the operator. If the latter valve is spring-loaded it will return to a position which effects continuity between lines 897 and 899, but this has no observable effect on the system at this point in the sequence: during filling, the air cylinder 885 is locked out of operation by the interruption of continuity at buttons 884, so that the operator cannot erroneously inltiate raising of the heads until the last one of the pistons has completed its cycle and restored continuity through buttons 884. First, however, the several rising pistons actuate theix respective "OUT" buttons, reversing the pistons at the tops of their respective strokes and continuing the filling cycles. ~7hen in fact the do~m~ard strokes are complete I

and continuity is restored through all buttons 884 the selector valve 891 can be reversed -- or if springloaded has already been reversed by earlier release of the foot pedal -- and the heads are raised together through applica-tion of air to cylinder 885 through 885b. The case of full bottles may then be removed, and a case of unfilled bottles placed in position for filling;
the system is then ready to begin a new cycle of operation as above described.

- 34 _

Claims (62)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Apparatus for at least partially filling containers with flowable substance from a source thereof, having a dispensing system comprising:
a volumetric metering chamber adapted to be connected to receive such substance from such source thereof, and within the chamber a biacting piston arranged for motion between positive stops, for establishing controlled volumes of such substance; dispensing means, downstream of the chamber, for discharge of such controlled volumes into such container along a discharge path terminating at an orifice from which such substance can pass directly into such container without passing along any intervening conduit; first means, in addition to hermetic sealing, for preventing or reducing access of gas to the chamber; and second means for preventing or reducing access of ambient air into the discharge path along substantially its whole length.

2. Apparatus as claimed in claim 1, wherein the dispensing means comprises a nozzle having a tip, the nozzle being adapted for insertion into such container to be filled and adapted to be operated to define a dispensing orifice; and the dispensing means are arranged to conduct the controlled volumes of substance from the chamber to the nozzle for discharge thereof; and the second means include means, responsive to insertion of the nozzle into such container in filling position, for permitting operation of the nozzle to define a dispensing orifice only when the resulting orifice is below a final fill level of such substance in such container so that, in operation, the orifice is submerged when the final fill level is reached and the orifice is then sealed while it is still submerged.

3. Apparatus as claimed in claim 2, also comprising suction means for removing drops of such flowable substance from the tip after each such discharge is complete, without affecting the body of such substance in the container.

4. Apparatus as claimed in any one of claims 1 to 3 wherein the volumetric metering chamber has a plurality of ports each of which, in operation, functions as a substance exhaust port of the chamber and each is at a respective elevation lower than the elevation of the dispensing means; and including means, connected to the chamber and to the dispensing means, capable of defining a flow path from each port of the chamber to the dispensing means; so that, in operation, bubbles in such flowable substance within the chamber tend to escape, along the flow path, by buoyancy to and through the dispensing means.

5. Apparatus as claimed in claim 1, wherein the volumetric meter-ing chamber has an inner cylindrical surface terminating in at least one shaped end wall, a port is formed in the chamber at the same end of the chamber as the said wall, and the bi-acting piston is positioned within the chamber and adapted for motion therein toward and away from said one end wall, to meter controlled volumes of such flowable substance out of the chamber via the port to the dispensing means; and wherein the piston has an end surface facing said one end wall, the end surface and end wall being so shaped as to expel from the chamber via the port any gas bubbles within the chamber at the end of an exhaust stroke when the said end surface most closely approaches the end wall.

6. Apparatus as claimed in claim 5, wherein the end surface and end wall are each inclined relative to the diameter of the cylindrical chamber surface, the respective inclinations being slightly different so that at the end of the exhaust stroke when the end surface most closely approaches the end wall the space between surface and wall is thickest in a region adjacent the port, whereby, in operation, bubbles in the chamber tend to be squeezed out of the chamber via the port, at the end of the exhaust stroke.

7. Apparatus as claimed in claim 5 or claim 6, wherein the end surface and end wall are each substantially conical, the apex angle of the conical end wall being slightly smaller than the apex angle of the conical end surface, and the port is formed substantially in the center of the end wall, whereby in operation bubbles tend to be squeezed toward the center of the end wall and out through the port.

8. Apparatus as claimed in claim 5 or 6, wherein the end surface is formed with a projection closely matched to the shape of the port, to assist in the expulsion of bubbles therethrough.

9. Apparatus as claimed in claim 1, which includes resilient means for effecting a sliding seal between the outer circumference of the piston and the inner surface of the chamber, so that, in operation, the piston forms a movable wall to define first and second subchambers, each having at least one port.

10. Apparatus as claimed in claim 1, wherein there are provided means defining an actuating surface movable with the piston; and the positive stops comprise limit means fixed relative to the chamber and located and adapted to engage the actuating surface, for mechanically defining one end of the piston stroke; and adjusting means, responsive to manual manipulation, for effecting relative longitudinal adjustment of the actuating surface and the limit means so that, in operation, the overall volume of such substance metered by the piston and chamber from such source into such container is adjustable by manipulation of the said adjusting means.

11. Apparatus as claimed in claim 10, wherein a plunger is attached to and movable with the piston, and extends longitudinally in a direction parallel to the motion thereof, through a sealed aperture in an end wall of the chamber, and the means defining the actuating-surface defining means are secured to the plunger outside the chamber.

12. Apparatus as claimed in claim 5, which includes a control system responsive to the piston, and comprising at least one member which is res-ponsive to the relative position of the piston with respect to the chamber, for reversing the motion of the piston at the end of each stroke; and actuating-surface defining means which move with the piston longitudinally;
and wherein the positive stops are longitudinally fixed relative to the chamber, and located and adapted to engage the actuating-surface defining means to halt the piston at each end of its stroke; and the apparatus also comprises means for adjusting the distance which the piston may move longi-tudinally relative to the chamber, between the two points at which the con-trol system responds to the piston and between the two points at which the actuating-surface defining means engage the positive stops so that, in operation, the amplitude of piston excursion is positively but adjustably defined.

13. Apparatus as claimed in claim 1, which includes means for adjusting the discharge flow rate of the flowable substance.

14. Apparatus as claimed in claim 13, wherein the means for adjust-ing the flow rate comprise a plurality of orifices of different cross sections and means for selectively positioning any one of the orifices in the path followed by such flowable substance.

15. Apparatus as claimed in claim 1, wherein the first means comprise means for filling the chamber by positive pressure, which means include a valve which is connected to a port at each of the two ends of the chamber and to the dispensing means, and which is also capable of being connected to such source, and which is arranged when set in one sense to direct such flowable substance from such source into a first port at one end of the chamber and to direct such substance from a second port at the other end of the chamber to the dispensing means and when set in another sense to direct such substance from such source into the said second port and from the said first port to the dispensing means.

16. Apparatus as claimed in claim 15, wherein the valve comprises a spool capable of sliding between two operating positions within a cylindrical housing, the spool being subdivided so as to define, in conjunction with the housing, a plurality of flow chambers which provide communication between appropriate inlets and outlets in the housing in accordance with the position of the spool.

17 Apparatus as claimed in claim 16, which in-cludes means for driving the spool from one operating position within the housing to the other, which com-prises two compressed-gas ports, one at each end of the valve housing, each communicating with a space within the housing and defined in part by an end sur-face of the spool, compressed-gas conduits for pro-viding physical communication between a source of gas under pressure and the said two compressed-gas ports, and control means, responsive in operation to the position of the piston in the chamber so as to apply the pressurized gas selectively via the com-pressed-gas conduits to one or the other end surface of the spool.

18 Apparatus as claimed in claim 17, wherein the first means also include isolating means for pre-venting transfer of compressed gas into the flow chambers, the said isolating means comprising: dual sealing means intermediate between each of the flow chambers and an associated one of the compressed-gas ports; the dual sealing means comprising in series a first resilient seal exposed on one functional side to the flowable substance and exposed on a second functional side to ambient air at atmospheric pressure, and a second resilient seal exposed on one functional side to ambient air at atmospheric pressure and on a second functional side to the compressed gas so that, in operation, partial failure of the first seal re-sults in pressurized leakage of the flowable substance to the atmosphere, and partial failure of the second seal results in pressurized leakage of compressed gas to the atmosphere, but in no case can failure of only (Claim 18 continues . . .) the second seal result in leakage of compressed gas into the flow chambers and passageways of the valve containing such substance, and in no case can failure of only the first seal result in leakage of such sub-stance to the compressed-gas port.

19 Apparatus as claimed in claim 16, which in-cludes electrical drive means for moving the spool be-tween its operating positions.

Apparatus as claimed in claim 1, wherein the dispensing means comprise a dispensing nozzle and which includes positioning means, attached to the dispensing means, for effecting relative motion between the dispensing nozzle and a container to be filled, wherein, in operation, the dispensing nozzle may assume a dispensing position within such container.

21 Apparatus as claimed in claim 20, wherein the second means include control means, also attached to the dispensing means, for sealing the dispensing nozzle when the nozzle is not in or nearly in the dispensing position, whereby the dispensing nozzle is opened to connect such source with such container via the metering chamber only when the dispensing nozzle is in or nearly in the dispensing position.

22 Apparatus as claimed in claim 21, wherein the control means are responsive to physical engage-ment of a portion of the apparatus with such container to be filled.

23. Apparatus as claimed in claim 3, wherein the suction means comprise a vacuum vessel within which, in operation, there is developed and maintained a negative pressure with respect to atmospheric pressure, a drip-catching orifice in the vicinity of the nozzle tip, vacuum conduits providing sealed physical communication between the vessel and the drip-catching orifice, and secondary control means for interrupting sealed physical communication between the drip-catching orifice and the vacuum vessel via the conduits, when the dispensing nozzle is in or nearly in dispensing position, and for restoring sealed physical communication between the drip-catch-ing orifice and the vacuum vessel when the dispensing nozzle is not in or nearly in dispensing position so that, in operation, the drip-catching orifice provides suction at the tip of the dispensing nozzle, but only above the prevailing level of such substance within such container being filled at any instant of time, for removing drips sub-sequent to filling.

24. Apparatus as claimed in claim 23, wherein the suction means also define a second orifice communicating between the vacuum conduits and the ambient air, and the secondary control means comprise means for sealing the second orifice when the dispensing nozzle is not in or nearly in dispensing position, and for unsealing the second orifice, to substantially remove suction at the tip of the nozzle, when the nozzle is in or nearly in dispensing position.

25. Apparatus as claimed in claim 24, wherein the second orifice is disposed near the position of a container's mouth during filling, so that, in operation, the second orifice provides suction at the mouth of the container, but always above the substance level in the container, for assistance in air removal from the container and for catching spray, during filling.

26. Apparatus as claimed in claim 1, wherein the first means comprise means for supplying flowable substance from the source to the chamber at a positive pressure relative to ambient atmospheric pressure.

27. Apparatus as claimed in claim 15, wherein the first means comprise means for supplying flowable substance from the source to the chamber at a positive pressure relative to ambient atmospheric pressure, and including resilient means for effecting a sliding seal between the outer circumfer-ence of the piston and the inner surface of the chamber, so that, in operation, the piston forms a movable wall to define first and second sub-chambers in which are located said first and second ports respectively, and wherein, during a first half-cycle of operation, the valve provides physical communication between the first subchamber and the source, so that, in operation, pressurized substance from the source forcibly moves the piston, enlarging the size of the first subchamber and reducing the size of the second subchamber, filling the first subchamber with the substance, and provides physical communication between the second subchamber and the dispensing means, so that, in operation, reduction of the second subchamber forcibly moves the substance out of the second subchamber to the dispensing means; and during a second half-cycle of operation the valve provides physical communication between the second subchamber and the source, whereby pressurized substance from the source entering the second subchamber forcibly moves the piston, enlarging the second subchamber and reducing the first subchamber, and provides physical communication between the first subchamber and the dispensing means.

28. Apparatus as claimed in claim 20, wherein the dispensing means comprise a supply hood provided with tubing seals; a tip-support structure and at the remote lower end thereof an integrally attached, formed tip; an internal passageway adapted for connection to the metering chamber, for flow of such substance into the hood from the metering chamber; a supply sleeve comprising a tubing section, adapted to provide conduction of such substance to the container, mounted for longitudinal sliding motion relative to the hood while constantly sealed thereto by the tubing seals, and adapted for longitudinal compressive engagement with the tip, the tip being provided with at least one tip seal for sealing engagement with the tubing section from the supply hood; first compliant means limiting longitudinal motion of the supply sleeve toward the supply hood, and means, connected with the supply sleeve, and adapted for and responsive to engagement with the container to be filled, for urging the supply sleeve toward the supply hood, act-ing against the compliance of the said first compliant means, only when the bottom of the supply sleeve is inserted into such container to be filled, so that, in operation, longitudinal separation of the supply sleeve from sealing relation with the tip, to permit flow of substance from the metering chamber via the sleeve into such container only when the bottom of the supply sleeve is inserted into such container to be filled, is controlled by transmission of compressive force to the supply sleeve by the said urging means, from a container to be filled.

29 Apparatus as claimed in claim 28, wherein the dispensing means further comprise a vacuum hood comprising a tubing section mounted for longitudinal sliding relative motion about the tip support struc-ture and supply sleeve, and for longitudinal com-pressive engagement with the tip, and adapted to pro-vide communication between a point above at least one of said tip seals and a partially evacuated chamber, the said tip also having formed within it a suction conduit from the vicinity of the lower ex-tremity of the tip to a point above at least one of said tip seals, for sucking substance droplets from the lower extremity of the tip into the vacuum hood and toward the partially evacuated chamber, and second compliant means limiting longitudinal relative insertion of the supply sleeve into the vacuum hood, and the said supply sleeve urging means comprising means, connected with the vacuum hood, and adapted for and responsive to engagement with such container to be filled, for urging the vacuum hood toward greater in-sertion of the supply sleeve thereinto, acting against the compliance of the said second compliant means and thereby also urging the supply sleeve toward the supply hood, only when the bottom of the supply sleeve is insert-ed into such container to be filled, whereby longitudinal separation of the vacuum hood from sealing relation with the tip, to interrupt sucking of substance droplets from the vicinity of the lower extremity of the tip via said conduit toward the partially evacuated chamber when the bottom of the supply sleeve is within a container to be filled, is controlled by transmission of compressive force upon the vacuum hood via the said vacuum hood urging means from a container to be filled, as the dispensing means and the container are moved closer together, and so that, in operation, the said sucking of substance from the vicinity of the lower extremity of the tip is inter-rupted during said flow of substance from the source via the sleeve into such container.

30. Apparatus as claimed in claim 1, which includes supply pipes which conduct the substance from the source to the metering chamber, and wherein the first means com-prise means for removing gas from the supply pipes.

31. Apparatus as claimed in claim 30, wherein the said gas-removing means comprise an enlarged portion of the supply pipes which defines a flow path for such substance whereby, in operation, gas bubbles within such substance rise to the top of the enlarged portion while such substance passes therethrough.

32. Apparatus as claimed in claim 31, wherein the gas removing means define a gas-entrapment dome and an inlet thereto disposed for communication with the top of the said flow path and toward the down-stream end of the said enlarged portion; and release means, responsive to the quantity of gas accumulated within the dome, for discharging gas from the dome to maintain such substance level therein above the top of the flow path; so that, in operation, the pre-cise control of said volumes discharged into such containers is protected from variations which would otherwise result from discharge of entrained gas with such substance.

33. Apparatus as claimed in claim 16 when dependent on claim 10 wherein the means defining an actuating surface are movable within the piston in an "in" direction and in an "out" direction relative to the chamber, and there are provided sens-ing means disposed for actuation by the actuating sur-face, so as to sense the presence of the piston at each of its respective positive stops, and thereby when suit-ably excited to generate functional signals of such presence, the said sensing means comprising "IN"
sensing means disposed to sense presence of the piston at a first one of its two positive stops and in addi-tion "SYSTEM READY" sensing means disposed to sense a ready condition of the apparatus with respect to filling a particular container, and first functional signal interconnection means between sensing means and the spool valve, adapted to drive the valve-spool to its position which initiates a filling cycle by actuating surface motion away from the "IN" sensing means only when the "IN" and "SYSTEM READY" sensing means are initially simultaneously actuated, whereby initiation of a half-cycle of operation away from the "IN" sensing means is contingent upon completion of the previous half-cycle of operation toward the "IN" sensing means.

34 Apparatus as claimed in claim 33, which in-cludes a plunger attached to and movable with the piston, and extending longitudinally in a direction parallel to the longitudinal sliding motion of the piston relative to its chamber, through an aperture formed in an end wall of the chamber, the aperture being provided with compliant seal means to permit sliding motion of the plunger therethrough in the "in" direction and in the "out" direction while main-taining pressurization of the chamber, the actuating means being secured to the plunger outside the chamber and remote from the end fixed to the piston.

35. Apparatus as claimed in claim 33, which in-cludes second functional signal interconnection means between the sensing means and a signal utilization means, for actuation of signal utilization means if the "SYSTEM READY" sensing means are actuated but the "IN"
sensing means are not actuated so that, in operation, further apparatus operation may be made contingent upon response to the signal utilization means.

36. Apparatus as claimed in claim 35, wherein the utilization means comprise an alarm for alerting a human operator when the "SYSTEM READY" sensing means are actuated but the "IN" sensing means are not actuated.

37. Apparatus as claimed in claim 35 or claim 36, wherein the utilization means comprise shutdown apparatus for interrupting transport of containers to and from the apparatus.

38. Apparatus as claimed in any one of the claims 35 to 37, wherein the utilization means comprise shutdown apparatus for interrupting flow of substance from the source.

39. Apparatus as claimed in claim 35, wherein the sensing means are pneumatic devices and are pneumatically excited and the utilization means are pneumatically actuated.

40. Apparatus as claimed in claim 39, wherein the utilization means comprise shutdown apparatus for de-pressurizing the pneumatic devices.

41. Apparatus as claimed in claim 35, wherein the sensing means are electrical devices and are electrically excited and the utilization means are electrically actuated.

42. Apparatus as claimed in claim 41, wherein the utilization means comprise means to interrupt the elec-trical excitation to the apparatus, including the excita-tion to said electrical devices.

43. Apparatus as claimed in claim 33, wherein the said sensing means comprise, in addition, "OUT" sensing means disposed to sense presence of the piston at a second one of its two positive stops and the first interconnection means are further adapted to drive the valve spool toward that position which initiates plunger motion toward the "IN" sensing means only if the "OUT" sensing means are actuated, whereby, in operation, initiation of each half-cycle of operation is contingent upon completion of the previous half-cycle.

44. Apparatus as claimed in claim 43, which includes "CONTAINER READY" sensing means arranged to sense the presence of a container in a filling position and further functional signal interconnection means between the sensing means and the spool valve, adapted to drive the valve spool to its position which, in operation, initiates actuating surface motion toward the "OUT"
sensing means only when the "IN" sensing means and "CONTAINER
READY" sensing means are initially simultaneously actuated, and to drive the valve spool toward that position which initiates actuating surface motion toward the "IN" sensing means only if the "OUT" sensing means are actuated; whereby, in operation, initiation of the first half-cycle of operation is contingent upon presence of a container, and initiation of the second half-cycle is contingent upon completion of the first half cycle.

45. Apparatus as claimed in claim 16, which includes means for indicating whether the spool within the valve has moved.

46. Apparatus as claimed in claim 45, wherein the indicating means comprise a transparent wall section forming at least a portion of the housing of the spool valve.

47. Apparatus as claimed in claim 45, wherein the indicating means are responsive to functional signal transmission from the "IN" sensing means.

48. Apparatus as claimed in any one of claims 45 to 47, which includes means for freeing the spool within the valve in the event the indicating means indicate that the spool is stuck.

49. Apparatus as claimed in claim 43 or 44, where-in the first functional signal interconnection means between sensing means and spool valve are further adapted to drive the valve spool toward that position which initiates plunger motion toward the "IN" sensing means only if the "OUT" sensing means are actuated while simul-taneously the said "SYSTEM READY" sensing means are not actuated, whereby continual reciprocating operation of the spool and piston is inhibited if the apparatus is stopped in a "system ready" position, thereby preventing multiple overfilling of a container.

50. Apparatus as claimed in claim 44, which in-cludes means for deactuating the "CONTAINER READY"
sensing means when apparatus operation is interrupted.

51. Apparatus as claimed in any one of claims 1, 2 or 3, which includes storage means which comprise the source of flowable substance.

52. Apparatus as claimed in any one of claims 1, 2 or 3, which includes means defining a support for containers when they are being filled.

53. Apparatus as claimed in claim 1, which comprises a plurality of volumetric metering chambers, each having a corresponding biacting piston, arranged for motion between positive stops establishing individually control-led volumes of such substance, and a corresponding plurality of dispensing means for discharging such controlled volumes into containers, the apparatus being arranged to receive flowable substance from a single source thereof.

54. Apparatus as claimed in claim 10, which comprises a plurality of volumetric metering chambers, each having a corresponding biacting piston, as herein defined, arranged for motion between positive stops establishing individually controlled volumes of such substance, and a corresponding plurality of dispensing means for discharging such controlled volumes into containers; the apparatus being arranged to receive flowable substance from a single source thereof, and which includes means for simultaneously ad-justing, from a common control, the relative positions of the stops with respect to each of the actuating surface defining means so that, in operation, the overall volume dispensed from each of the plurality of piston-chamber combinations can be adjusted in common with that from each of the others of the plurality, even while the apparatus is in operation.

55. Apparatus as claimed in claim 54, wherein the common adjustment means comprise means for mounting all the chambers for common parallel motion of all the pistons and actuating surfaces and means for mounting all the limit means individually to a common plate, the said plate being mounted adjustably for motion parallel to the said common parallel motion, thereby providing adjustment of one limit of each piston's stroke from a single common control.

56. Apparatus as claimed in claim 53, wherein the said plurality of chambers rotates about a common axis, and the apparatus includes means for effecting corresponding rotation of such containers to be filled.

57. Apparatus as claimed in claim 1, wherein the first means comprise conduits and flow-control means which in operation cooperate to charge the chamber with such flowable substance by positive pressure.

58. Apparatus as claimed in claim 57, wherein the flow-control means comprise valve means for reversing the direction of flow into and out of the chamber, whereby, in operation, such substance charged into the chamber in each half-cycle of the biacting piston is expelled from the chamber in the next half-cycle.

59. Apparatus as claimed in claim 3, wherein the suction means com-prise a vessel, means for establishing within the vessel a negative pressure with respect to ambient atmospheric pressure, conduit means providing physical communication between the interior of the vessel and the immediate vicinity of the nozzle tip; and drip-catching control means for interrupting said communication during discharge of said controlled volumes, and after each such discharge while the nozzle tip contacts the body of the substance in such container, so that, in operation, drops of such substance are sucked via the physical communication means and away from the immediate vicinity of the nozzle tip after each such discharge, but not until the nozzle tip is moved out of contact with the body of the substance.

60. The apparatus of claim 54, also having means disposed along the flow paths of the substance for individually adjusting the discharge flow rates of the substance to the respective containers so that they may be equalized.

61. The apparatus of claim 1 wherein: the dispensing means comprises a nozzle and the second means comprise a sealing tip adapted to fit tightly against the end of the nozzle externally thereto, the tip being operable to become spaced from the nozzle externally thereto, to define therewith a dispensing orifice.

62. The apparatus of claim 1, wherein the amplitude of the said motion is adjustable.