CA1174209A - Down flow apparatus for dispensing viscous material and method of loading same - Google Patents

Abstract

DOWN FLOW APPARATUS FOR DISPENSING
VISCOUS MATERIAL AND METHOD OF LOADING SAME
Abstract Simple apparatus permits material, such as a hand cleaner whose viscosity is too great to flow downward under the force of gravity, to be loaded by inverting a can of the material and pressing downward onto the top of a reservoir sleeve. For pumped dispensing, two rubber valves of the "duck-bill" type are provided in the flow line downward from the reservoir bottom wall. While their lips are so soft as to be unable to restrain the down flow of conventional liquid, this is no problem when used with the viscous material. The material is dispensed by pumping until its level in the reservoir is so low that an air channel forms downward through the material to the valved flow line, preventing further dispensing. At this stage, inverting and pressing downward a second can of material drives air in the reservoir downward through the air channel so formed and out through the soft rubber valves, so that dispensing can recommence.

Description

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DO~N FLOW APPARATUS FOR DISPENSI'NG
VISCOUS MATE~IAL AND METHOD OF LOADING'SAME

Technical Field:
This invention relates to a di:spenser for hand cleaners and the 5 like whose viscosity is too great to ~low downward under force of gravity and the method of loading same.

Background Art:
A popular type of hand cleaner, used especially in factories, garages and other industrial and commercial establishments, is of a lO viscosity much like that of a pasty creme, too great to flow downward under the force of gravity. Dispensing such a material involves prob~
lems different from those of dispensing a flowable liquid. Loading and reloading of such dispensers has offered serious problems, particularly with regard to the channeling of air through the material on dispensing 15 and the elimination of air in refilling dispensers.
Such hand cleaner material may be furnished in cylindrical cansi and these may be left in place over a cylindrical reservoir for the materialg as shown in U. S. Patents No. 2,818,998 to Jones and 3,809,293 to the present inventor. In the types of dispenser there shown, when 20 the reservoir is partly filled an additional can of material may be so put in place over it, to descend as the material within the reservoir is pumped from it; this descent is caused by outside air pressure, acting against the vacuum induced by the dispensing action. In both of these patents the problem of charging a partially-filled dispenser and elimi-25 nating the air between-th.e mate.ri.al already in the reservoir and the new materi:al to be added is met by pr~v;:di'ng a verti:cal pi'pe within the reservoir, closed at its top end and having a series of orifices at its sides so that the interveni'ng ai.r, at any level, may be forced into t '7 ~ 9 pipe and discharged downward duri.ng the filling operation. Of these patents, No. 3,802,293 sh.ows. that the vi:scous material may be drawn out by being pumped in a downward course leading from the bottom of the reservo;r through a ball valve and thence. pressed by a pis:ton through a 5 second ball valve to a discharge outlet.

D;sclosure of Inventi.on:
The present ;.nvent;on prov;.des much s;:mpli`f;:ed apparatus and an entirely new method of loadi:ng and reloading the apparatus with such viscous material. With the present method and apparatus, it is pre-ferred that the reloading (or at least a f;nal act thereof~ take place when the level w;thin the reservo;r is so low that pumping has formed an air channel through the materlal, pre.venti.ng further dispensi:ng. At this time the superimposed container of the material is merely pressed downward, driving out air through the ai:r channel so formed and the two lS readily-opening rubber valves in the pumpi.ng system. Th.is reloading takes place without any pumping act;on and w;thout need for any such vertical air vent pipes.
To achieve the present method of dispens;ng material whose viscos-ity is too great.to flow downward under force of gravity, I provide a 20 dispenser similar in certain respects to:those of the prior patents.
Thus, the hollow cylindrical reservoir, presented vertically, has a vertical air inlet groove formed in its outer surface, and a notch in the upper cylinder edge connecting the groove to the interior, for commun;cating air flow. A bottom reservoir wall which supports the 25 cylinder includes a valve, preferably formed integrally of a rubber-like material and popularly known as a "duck bill" valve, of sufficient capacity to permit down-flow of the material under vacuum caused by reciprocating a dispensing piston, which in the preferred embodiment operates on a horizontal axis forwardly of the valve outlet. The piston 30 is hollow and communicates with the hollow of a piston rod leading outward to and through a dispensing knob. At the juncture of the hollow piston and rod there is housed a second valve of the same type, which because of the small space afforded mus.t b.e su~s~tantially smaller; the force applied by the pi.ston, and res.i.ste.d on the closi`ng of the. fi:rst 35 valve, may create a pres5ure.sub~stantially exceeding atmospheri:c pressure, which alone is avaîled of for driving th.e vi:scous material through the smaller valve.
Heretofore, the formation of an air channel through the material in the reservoir as its level lowered, was a serious problem. In using the present dispenser, the air channel, formed through the viscous material S when its level in the reservoir is low, is utilized to facilitate re-loading. Assuming reloading has been delayed to this point, a new can of material is applied by inverting and pressi`ng down over the reservoir sleeve. Since the sleeve fits closely against the inner surface of the can of material, the material is readily introduced downward into the reservoir by manual pressure, and the intervening air above the level of the old material is easily driven out by such pressure tnrough the two valves.
If, however, the user has preferred not to wait unti:l the air channel forms, but places a new can of material on top of the reservoir prior to such channeling, the intervening ai`r cannot be driven out; the can may move down only slightly below the top edge of the reservoir sleeve, leaving a large amount of air intervening. After this, drawing the material from the dispenser will cause the newly added can of material to telescope gradually downward, with its material separated from that already in the reservoir by the intervening air. As soon as the level of the material previously within the reservoir has lowered sufficiently to form an air channel, the dispensing will stop until the air below the newly added material is exhausted. This is done readily by applying manual pressure at that time to the bottom of the can, quickly driving the air through two duck bill valves in the dispensing passage.

The Drawing:
FIG. 1 is a side view, principally in section, showing a preferred embodiment of the present invention, with a can of material being supplied to fill an empty dispenser, air being driven out through the valves.
The phantom lines show the final position of the can.
FIG. 2 is an enlarged detail view, after filling, of the dispenser of FIG. l, show1ng th~ piston drawn for~ard to commence dispensing.
FIG. 3 is a detail view similar to FIG. 2~ with the dis-pensing piston pushed back, thus applying superatmospheric pressure to close the first valve in the line of flo~ and di`spense the material through the valve in the piston.
FIG. 4 illustrates how, when the le.vel of the material has lowered sufficiently, drawing the piston forward will form an ai:r channel through the material, thus terminati:ng di:spe.nsing.
FIG. 5 illustrates how, aFter an ai:r channel has formed as in FIG.
4, supplying a new can of materi.al drives out the air through the air channel, so that dispensing may re.commence. as i.n FI~. 2.

Best Mode for Carrying Out the Invention:
The wall-mounted dispenser shown in the drawings has a dispenser body generally designated 10 prefe.rahly formed by molding a conventi:onal plasti'c material suited to the proportions descri.l~ed, such as hardened polyethylene. It has a generally cylindrical body portion ll backed by an integral flat wall flange 12. The generally cylindrical ~ody portion ll is formed about a vertical axi:s:, not shown. Near its lower end, the 15 body 10 has a forwardly projecting hori:zontal cylindrical boss 13 formed about the axis of a pump bore 14 which penetrates a60ut two-thirds or more of the diameter of the body portion 11. At the forward end of the pump bore 14 is a counterbore portion 15.
At its upper end, a circular upper surface 17 of the dispenser body 20 11 is prbvided, referred to here;nafter as the bottom wall of the reser-voir. It is surrounded by an upstanding reservoir mounting flange 18.
Molded in the dispenser body and extending downward from the surface 17 to the rear end of the pump bore 14 is a downflow passage 21 having a counterbore portion 22 extending downward from the reservoir bottom wall 25 17 and threaded as shown. The intersection of the downflow passage 21 with the counterbore 22 provides a shoulder 24. The downflow passage 21 has a bottom outlet 25 into the aft end of the horizontal pump bore 14.
A molded plastic externally-threaded hold-down washer 27, which screws into the counterbore 22, holds in place the larger of two valves 30 used in the dispensing apparatus. The preferred valve is of the "duck-bill" type, generally designated 30. It is molded of soft, natural or synthetic rubber material, and has a hollow cylindrical body portion 31 molded with an integral upper flange. 32 $eated against the shaulder 24, and integral soft lips 33 which. project do~nstream toward the battom 35 outlet 25 of the downflow passage. 21.
Mounted in the pump bore 14 i's. a piston assemb.ly generally des.ignated 40. rt includes a piston rod or plunger 41 naving a dis.charge passage ., ~4~

42 which extends longitudinally forward through it and then downward through a forward end knob porti.on 43 to a di.scharge. outlet 44. The inner end 46 of the piston rod 41 i:s externally threaded.
In the embodiment shown, the hollow plunger 41 has along i:ts lower 5 edge a longitudinal rib 48 whi:ch. is accommodated i:n a notch 4~ formed in a hollow cylindrical retainer plug 50 fitted into the counterbore 15 and there retained, as by a removable screw, not shown. The retainer plug functions also as a guide to the plunger 41, while its notch. 4~ holds the plunger from rotati:on so that its discharge outlet 44 wlll always be 10 presented downward.
Onto the inner end 46 of the plunger 41 is fitted a hollow cyli'ndri-cal piston generally designated 55 penetrated by an axial bore 56 and having an exterior piston seal 57, such. as an O-ring fitted within a groove, the piston 55 also has a counterb.ored th.readed inner end 58, the 5 counterbore providing a shoulde.r 59 at its juncture with. the bore 56.
The shoulder 59 is spaced from the edge of the piston rod inner end 46 sufficîently to provide a shallow annular cavity which accommodates the annular flange 64 of a smaller valve generally designated 65, whose construction is generally similar to the larger valve 30. Thus, the 20 smaller valve 65 has a hollow cylindrical body portion 66 terminating in molded lips 67 which extend downstream, the body 66 and lips 67 being accommodated within the discharge passage 42 of the plunger 41.
Mounted on the dispenser body 10 within the reservoir mounting flange 18 is a generally cylindrical metal reservoir sleeve 70. Its 25 lower circular edge 71 is retained at the reservoir mounting flange 18.
As shown above the top edge of the mounting flange 18, the wall of the sleeve 71 has a vertical inwardly-formed air-conducting groove 72 lead-ing from a lower inlet 73 upward to an inlet notch 75 in the reservoir upper edge 74.
The material to be dispensed is furnished in cylindrical cans 80 shown schematically and not part of this invention other than in its use in the method hereof. As shown in the drawings, the can 80 is of such height that when inverted and pressed down, the outer surface of the reservoir slee.ve will slide closely against the inner surface of the 35 wall of the can 80, and when its. hottom s.urface rests agains-t the upper edge of th.e upper edge 74 of the. reserYoir sleeve, the mouth. of the can 80 will be sufficiently above the reservoir mounting flange 18 as- to ,...

leave open the lower inlet end 73 of the groove, for supply of air therethrough.
The arrangement of the two valves 30, 65 is superficially familiari they are arranged in a flow li:ne i.n pumping relationsh.i:p re~lati:ve to each other. In fact, they would not ;.n th.is arrangement perform a usual pumping function; because their li:ps 33, 67 are so softly resilient as to be incapable of themselves restrai:ning the downflow of a liquid if filled within the reservoir 70.. However, when used with a material whose viscosity is too great to flow downward under force of gravity, such as the pasty hand cleaners heretofore referred to, there is no need for secure closing. Furthermore, the larger valve 30 must have sufficient flow capacity so that the small amount of vacuum, furnished by the atmospheric pressure when the pi:ston assembly 40 is drawn forward, will permit downflow through the valve li:ps 32. ~ersons skilled in the art will recognize that greater than atmospheric pressure is available to open the lips 67 of the smaller valve 65; becausP for this purpose all the force which may be exerted manually on the knob 43 is available.
Accordingly, the valves 30, 65 are molded of the same soft rubber or rubber-like compounds with their lips 33, 67 presented against each other lightly.
The foregoing description shows that the present dispenser, though intended to dispense material whose viscosity is so great as to defy dispensing by ordinary means, nevertheless has fewer parts than con-ventional dispensers and substantially fewer parts than prior dispensers for such special material. To operate with such simplified construction, the following method is used:
As seen in FIG. 1, a can of the material too viscous to flow under force of gravity is inverted and pressed downward about the reservoir sleeve 70. Since the inner diameter of the sleeve 70 is somewhat less than the inner diameter of the can, the material will be slightly in advance of the mouth of the can. As pressed downward with manually exerted force, illustrated by the downward arrbws above the can in FIG.
1, air in the empty dispenser wi.ll b.e driven out, dilati.ng and passing through the lips of the va.lve 30., 6~; and for th.ic purpose the piston assembly 40 may remain in its normal re.tracted pos:ition as sh.own. When the air is dri.ven out, the mate.ri:al w.i.ll fi:ll the reservoir. Tfiereafter when the piston plunger 41 is. drawn. ~orward as shown in FI:G~ 2, air 7~ 9 under atmospheric pressure enteri.ng through. the inlet 73 of the groove 72 will exert atmospheri.c pre.ssure on the material, so that the readily opening larger valve 30 will be dilated as the piston assembly 4~ i:s drawn forward. As this assembly i:s drawn forward, the lips 67 of the smaller valve 65 are driven sealedly agai:nst each other.
Thereafter, as shown in FIG. 3, ~hen the knob 43 i:s dri:ven backward, the piston 55 will exert pressure on the. material b.ehind it in the pump bore 14, causing the lips 33 of the larger valve 30 to be pressed tightly together while the pressure simultaneously opens the lips 67 of the smaller valve and causes the material to pass forwardly through discharge passage 42 and out the discharge outlet 44. The material is dispensed by continued forward-and-aft strokes of the piston-assembly 40, with the air which enters through the groove 72 and the reservoir sleeve 70 continuing to supply atmospheric pressure on the upper surface of the material within the reservoir.
When the level of the materi.al lowers to about 10% to 20~ of the depth of the reservoir (depending on consistency of the material, hei:ght of the reservoir and other obvious considerations) at some such level air will "channel" through the material as shown in FIG. 4, so that it is impossible to draw any more of the contents outward through the dispensing system. At this point, assuming there has not been any prior effort to refill the reservoir, a new can of material is inverted over the reservoir and driven downward as shown in FIG. 5; and it is pressed downward with a manually-applied force, this creating a superatmospheric pressure. The air channel which has so interrupted dispensing now provides a channel of out-flow for the air which had theretofore filled the top of the reservoir sleeve 70. This air flows out readily through the air channel and through the two valves as shown in FIG. 5 until the can is so lowered that its contents fill the reservoir, eliminating the air channel. Thus, pumped dispensing may be resumed.
The prior art dispensers referred to at the beginning of this specification were intended to make it possible to add a second can of the material while the reservoir contents were still substantial, that is, be.fore such an air ch.anne.l had formed. To achieve that advantage, the prior art dispensers were much. more complicated to build. Such advantage can be achieved only in part wi:tn.the present dispenser; to add such a second can of materi;a1, i:t may he inverted and Pres-s-ed down ....

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slightly below the top edge of the reservoir sleeve 70 and left ;n place, to descend gradually on the cushion of air between it and the material therebeneath, as that lower material is gradually dispensed.
If this method of operat;on is ut;lized, once the air channel forms as in FIG. 5, the user merely applies a slight manual force on the top of the can, driving out the intervening air through the air channel so that the dispensing may be recommenced.
Thus, using material which is too viscous to flow under force of gravity, I have taken advantage of the use of rubber-like valves whose lips are too soft and flaccid to restrain downflow of an ordinary liquid. The prior art recognized that such valves might be used for pump dispensers of the upflow type, but this would require at least a dip tube to conduct the liquid upward, and such dip tubes are a source of service difficulties, being likely to come loose. Accordingly, the present invention serves the purpose of dispensing a material which cannot be handled in ordinary dispensers, yet with fewer parts than ordinary dispensers require.
While the claims speak of material whose viscosity is too great to flow downward under force of gravity, it is understood that this is a generalized description of materials which do not flow readily under force of gravity under ordinary conditions of temperature and the like.
The reference in the claims to "manual application of super-atmospheric pressure" means the addition of a small positive force, readily applied by hand, to supplement the atmospheric pressure present.
The principle manifest in the present invention may be utilized with other positioning of component parts, such as the second valve and the flow outlet; thus, they need not be in the piston but may be in some cases advantageously located elsewhere in the line of flow. However, the present arrangement is particularly advantageous because there is no tendency of viscous material to drip out of the horizontal flow passage 42. Nevertheless, from this specification, modifications will be apparent to persons skilled in the design and construction of dispensers.

Claims (2)

Claims The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. The method of driving out air while loading and re-loading creamy material whose viscosity is too great to flow downward under force of gravity, into a dispenser of the type having a reservoir and, in the line of flow therefrom to a discharge outlet, two valves and a reciprocating piston between the valves adapted to open and close the valves alternately, the valves being of the type having rubber-like lips too soft to restrain downflow of a liquid, comprising the steps of introducing into the reservoir from above, such material in a quantity sufficient to fill the reservoir to such level as will avoid channeling of air through the material to the line of flow, pressing such material toward the reservoir bottom and thereby causing both the valves to open simultaneously and the intervening air beneath such material to be driven out therethrough, and then, on dispensing the material by recipro-cating the piston until the material level so lowers that a downward leading air channel forms to the line of flow, repeating the said steps of introducing, pressing and causing both valves to open simultaneously, thereby driving out the intervening air between such added quantity of material and any material already in the reservoir.

2. For dispensing creamy material of viscosity too great to flow downward under force of gravity, a dispenser comprising a hollow cylindri-cal reservoir having a bottom wall and a sleeve formed about a vertical axis, whereby a can whose inner diameter is slightly greater than the outer diameter of the sleeve and containing such material may be inverted and pressed downward thereover, and means to provide a line of flow from the bottom of said reservoir including serially a first valve, a pump piston, a second valve and a discharge outlet, whereby the reciprocation of said piston opens and closes said valves alternately with each other, each of said valves being of the type which has, projecting downwardly in such line of flow, a pair of rubber-like lips too soft to restrain downflow of a liquid, whereby when the level of such material in the reservoir so lowers that a downward leading air channel forms therethrough to said first valve and when a new supply of such material has been added thereover with air intervening, manually pressing downward on such new supply opens said first and second valve simultaneously to drive out the air in such air channel, so as to permit renewed dispensing.