A proportioning and mixing device for dispensing under pressure a liquid solution having an excellent ratio accuracy irrespective of solvent gauge pressures and liquid solvent and/or solute temperatures, including a multi-stage jet proportioning and mixing device in the first stage of which the solute is free flowing at atmospheric pressure and is aspirated from a mixing chamber by kinetic flow energy of the solvent at a constant rate of flow from a smaller orifice directed through the mixing chamber to entrain solute therefrom and aspirate it into and through a larger orifice beyond which the kinetic flow energy is converted back to pressure in an expanding wall chamber. This pressure rise output enters the gap of the second stage whereupon it is acted upon by the flow from the input orifice and the resulting mixture is directed through an output orifice and then converted back to pressure. This process is repeated in subsequent stages. The output of the final stage flows through a final orifice which may be less but not larger in flow area than output orifice of the last stage, thus, establishing a stabilizing back pressure on the proportioning and working pressure for mixing and dispensing the mixture that maintains liquidity of the solute, solvent and their mixture at all mixing stages, and working temperatures, with or without a conduit used between them, the final proportion of the solution being the multiplicand of accurate liquid solution proportions of the individual stages.

BACKGROUND OF THE INVENTION 
In the proportioning of a miscible solute in a water solvent under 
continuous flow, objectionable ratio variation of over 50% can occur in 
the simple low cost conventional systems because of pressure variations or 
temperatures in either the solvent and/or solute supply. The conventional 
practice particularly with portable units has predominantly become the use 
of either one of two designs in single stages as related to the relative 
pressure of the solute at the mixing chamber, both having their advantages 
and disadvantages: 
(1) High Vacuum, restricted solute flow: A mixing system which develops a 
deep vacuum condition approaching zero p.s.i. absolute in the first mixing 
stage, for the purpose of conducting the solute through a flow restriction 
at the mixing chamber level in order to meter thereby the amount of solute 
supplied for a desired ratio proportioning that is related to the flow of 
solvent into the mixing chamber. Advantage: The use of high vacuum reduces 
the significance of lift height variations on the solute supply pressure 
to the flow restriction; or, Disadvantage: proportioning accuracy is 
affected by solvent pressures and the system is not suitable for low 
ratios due to difficulty of maintenance of high vacuum in such cares. 
(2) Low Vacuum, free solute flow: A mixing system in which the pressure 
acting upon the solute in the confluence chamber is essentially the free 
flow low vacuum lift height variations of the solute. Advantage: 
Proportioning is essentially independent of variations in solvent 
pressure. Disadvantage: lift height variations adversely affect 
proportioning accuracies for single stage mixing systems and high ratios 
are difficult to achieve in a single stage due to close mechanical 
tolerances required for proportion orifices. 
In applications where hot solvent and/or solute is being proportioned and 
used, vaporization of either liquid induced by low pressure can change the 
proportioning ratio. 
Since the degree of vaporization is related to the extent of vacuum 
existing in the primary mixing gap, this vaporization effect is much more 
deleterious in the high vacuum mixing system, and thus the minimal effect 
of vaporization is another advantage of a low vacuum system. 
Although either system is quite accurate if the exact design solute and 
solvent pressures are used and their relationship remains constant, only a 
small percentage of the commercial market would be satisfied and the 
danger of improper solution when higher temperature liquids are used due 
to the vaporization effect still confronts most of the users. 
Thus, at conventionally tolerated performance ratios which are available, 
the solute metered flow system is generally used as limited to ratios 
above a 1 to 10 and the free flow solute system limited to ratios below 1 
to 24. Two-stage conventional high vacuum gap proportioners may provide a 
better pressure output efficiency, but they perform no better than single 
stage proportioners with respect to ratio variations caused by the solvent 
pressure and solvent and/or solute temperatures. 
SUMMARY OF THE INVENTION 
The present invention provides: a mathematically standardized, low cost, 
portable, continuous proportioning-mixing-dispensing procedure and system 
with a free flowing solute that essentially eliminates variations in the 
proportioning ratios caused by variations in solvent pressure and/or 
vaporization of solvent and/or solute; is controlled by the actual ratios 
of the flow port areas for use in mass produced proportioners that deliver 
a predictably accurate ratio generally within a variation of plus or minus 
5%; provides a substantially complete range of usable ratios including the 
high ratio range which economizes on container sizes for concentrated 
solutes; and performs thusly over the expected range of municipal water 
supply pressures above a low gauge pressure that is selected as adequate 
for dispensing and ecologically safe against possible backflow 
contamination of water supply. The first stage protects the later stages 
against variations in ratio and the final output opening protects the 
preceding stages with back pressure against pressure variations therein 
other than possible changes in the first stage due to lift height changes. 
"Variation in ratio" as used here is sometimes referred to as degradation 
and means a plus or minus change in percentage ratio from the designed 
percentage ratio. The multi-stage mixer has at least two stages in which 
the output of the first stage is the solute under positive pressure for 
the next stage. 
Readily interchangeable inexpensive mixers with fixed ratio stages and 
nominal flow rates are provided for selective use if a different solution 
ratio is to be dispensed by the same gun. 
Each mixing stage of the invention basically comprises a mixing zone at the 
confluence between a free flowing solute and a jet of solvent that 
entrains the solute and ejects the mixture coaxially through an outlet 
port. A converging wall nozzle having an inlet port opening into the zone 
accepts solvent under pressure and converts it to kinetic energy in the 
jet and the outlet port having a larger flow area generally leads to a 
diverging wall passage that converts kinetic flow energy back to pressure. 
For ratio accuracy in the mixing zone the pressure of the solute entering 
said zone must be equal to the pressure of the mixture leaving the zone as 
it passes through the outlet port. At the first stage such pressure 
preferably is the environmental pressure in normal use thereby, and 
differs therefrom only by the pressure equivalent of the lift height, 
inter alia, maintaining a non-vaporizing pressure on the solvent and 
solute. Where the mixture from the previous stage is used as a solute the 
pressures at subsequent stages are the respective positive gauge pressures 
upon the mixtures after the reconversion from kinetic flow energy. 
With implementation of these conditions the mixture ratio provided at any 
zone is related to the ratio of liquid conducting flow areas of its inlet 
and outlet ports in percentage proportions of the mixture designed 
regardless of variations of solvent pressures. 
Furthermore, if any degradation occurs it will occur in the first stage due 
to variation of solute pressure and this degradation will be transmitted 
with minimal alteration in subsequent stages. Accordingly, the attainment 
of the ultimate ratio in the invention is divided in such a way that the 
first stage ratio is designed to be approximately that where minimal ratio 
variation occurs with variations in solute pressures, preferably a 1 to 4 
ratio (20% solution), with an accuracy better than plus or minus 10% 
within a lift height range of plus or minus 4 feet to accommodate the use 
of floor and shelf height solute supplies. The function of the subsequent 
stages is to provide an overall greater dilution and to reduce required 
production accuracy. 
The output of the last stage may be a directed jet discharge from the final 
outlet port without a diverging wall energy converter but preferably is 
provided with such a converter followed by a dispensing nozzle having a 
low pressure (soft flow) or an applicator nozzle ejecting at high pressure 
(hard flow) with or without an extension conduit being used. 
In either embodiment the flow area of the ultimate discharge outlet is not 
greater than the flow area of the outlet port from the last confluence, 
but rather smaller yet not small enough to cause a back pressure feedback 
through the system that would cause a degradation of ratio in the earlier 
stages. Accordingly, the "hard flow" embodiment is described herein since 
it can be used universally with either hard and soft flow nozzles also 
described herein. However, a "soft flow" embodiment maybe provided that 
has port areas designed for that purpose wherein the pressure at the 
confluence of each stage is essentially at atmospheric pressure rather 
than at increasingly higher pressures. The principles and concepts 
portrayed herein apply to both except the diverging wall sections at the 
outlet ports of each confluence chamber of the soft flow modification are 
shorter and convert only enough kinetic energy required to compensate for 
pressure losses occurring in the preceding stage. 
Preferably, all or only the critical inlet and outlet ports may be 
cylindrical for a short distance to minimize any enlargement thereof due 
to flow abrasion, and, the solute gauge pressures are effective at least 
within a distance equal to the radius of the respective outlet ports of 
the confluence chambers. 
Furthermore, in the present multi-stage invention it is preferred that the 
solution ratios of each stage be below 1 to 5. The lower the ratios the 
easier the manufacturing tolerances, the less the effect of port erosion 
in use, the lesser will be ratio variation in any stage, and the more 
stable the ultimate ratio under any unexpected changes in solute or 
solvent supply characteristics including temperature changes for hot 
liquid applications.

DESCRIPTION OF PREFERRED EMBODIMENT 
The invention will be described, by way of example, as related to the 
proportioning, mixing and dispensing of municipal water under pressures of 
15 to 100 p.s.i. serving as hot or cold solvent, and a chemical 
concentrate serving as a hot or cold solute having a free open flow for 
purposes of mixture entrainment in the first stage that is subject only to 
minor gravity influences, either positive or negative, if at all. The 
mixture is dispensed from a gun 10 under pressure through either one of 
two types of nozzles 12 with or without an extender conduit 14 between the 
nozzle 12 and the proportioning-mixer 16. 
The invention is illustrated as part of a manually controlled automatically 
vented proportioner-mixer-dispenser gun 10, such as illustrated in Hechler 
U.S. Pat. No. 3,862,640, connected to the outlet of a garden hose 18 to 
utilize municipal water pressure having a working pressure of 40 p.s.i.g., 
and the mixture is dispensed from the other end of the gun 10 as 
controlled by a person 19 holding and manipulating the gun to which a 
solute supply is connected. 
SOLVENT AND FLOW CONTROL 
The housing 20 inlet end 22 receives an adapter 24 (FIG. 2) selected for 
the source of solvent and it is held in place by screws 26. As shown, the 
adapter has a threaded opening 28 mating only with an outlet male fitting 
30 such as conventionally provided on a garden hose 18 for dispensing 
municipal water. 
The flow control and low positive gauge pressure venting is more 
particularly described in Hechler U.S. Pat. Nos. 3,862,640 and 3,984,053. 
Briefly, referring now to FIG. 2, the gun 10 preferably has the unitary 
housing 20 that provides an anti-contamination venting chamber 32 in which 
manual control of the flow of solvent through the compartment is provided 
by a dual valve arrangement in which a pilot valve 34 is opened first by a 
slidably manually operated actuator 36 with a low opening effort followed 
by equalization and a main valve 38 is then opened with a final low effort 
full opening. A backflow check valve 40 opens with the incoming flow and 
closes with no flow whether the flow control valves 34 or 38 are open or 
not. 
In controlling the solvent flow, the outer end of a stem 42 for the manual 
valve 34 extends in an axial direction through an opening 44 in a 
cross-wall portion 46 where a thumb handle 48 actuated manually operates a 
push rod 50 reciprocably mounted on the housing 20 to drive a T-shaped 
head 52 that actuates the valve stem 42 where it projects into a recess 54 
and selectively actuates the solute valve 56. At its rear end a manual 
release spring latch hook element 58 is provided selectively to hold the 
main valve 38 open for dispensing. 
For venting, the housing wall 20 is provided with large vent openings 60 
proximate to the inlet opening 28 bordered by reinforcement ribs 62 which 
guide two reciprocating valve members 64 and 66 therein that have movable 
side walls 64A and 66A defining two chambers 64C and 66C. When subjected 
to adequate water supply pressure, the walls coact with each other to 
close the vent openings at 60. However, end walls 64E and 66E are movable 
with their respective side walls and comprise valve elements for automatic 
venting as coordinated for predetermined coaction when normally separated 
by spring 68 at a low water supply gauge pressure. The strength of this 
spring determines the critical pressure at which mixing may proceed. 
Preferably, the spring 68 induces venting at and below 6 to 10 p.s.i.g. so 
that all backflow of mixture is prevented by continued forward flow of 
fresh water and the device is fully flushed and vented before zero p.s.i.g 
is reached. Above 10 p.s.i.g. the proportioner is operative for 
proportioning and dispensing a mixture as controlled by the manual flow 
control main valve 36. This venting pressure can be designed to be high 
for critical mixtures, if desired, as related to providing a minimum 
venting pressure below which the mixing and proportioning will not perform 
satisfactorily. 
SOLUTE SUPPLY 
The solute supply 70 is designed for wide open flow when used and although 
the supply tube 72 could lead directly to the mixing zone inlet opening 74 
it is preferred to valve the solute, ON or OFF, selectively and 
simultaneously with the water, through a mechanical connection 76 with the 
manual actuator 36 when solute is used to maintain prime. The solute valve 
56 is located on top of the outlet end 80 of the housing 20 as a unit 81 
to the rear of the thumb handle 48 and the valve 56 being spool shaped the 
valve housing 83 has two cylindrical slide portions 82 and 84 of different 
diameters separated by a tapering shoulder 86 for ease of assembly with a 
spring 88 for normally closing the valve which is retained closed by 
pressure differentials across the valve effected by the area of the head 
90 of the spool valve 56 exposed to atmosphere being greater than the area 
of the head 90 thereof exposed to the solute valve inlet port 92 when 
closed. Thereby, any drop in pressure in the intermediate space 94 when 
open through the passage 96 to the opening 74 will tend to hold the valve 
56 closed. 
During a mixing operation with the solute and solvent valves open the free 
flowing solute is under approximately zero gauge pressure within 2 
p.s.i.g. and the converging solvent nozzle converts solvent pressure to 
approximately zero gauge pressure in the first stage mixing chamber. When 
the solute valve 90 is opened it is desired that the solute flow as freely 
as the solvent can ingest it. When closed the mixture trapped beyond the 
valve 90, being liquid solid, will not respond to any aspirating effect 
except vaporization, if hot, which would be quite imperceptible. The load 
on the solute push rod 50 due to the spool valve is generally quite modest 
yet can be at a temperature qualifying as a hot wash without vaporizing at 
atmospheric pressure in the mixing operation. On the other hand, if hot 
solvent alone is being dispensed, there is no load from the spool valve 
involved with the push rod 50 and any unsatisfied aspirating effect 
against the internal balances between the spool valve heads with the 
atmospheric pressure against the head 81 urging closure of the valve head 
90. 
Either plain solvent or a chemical solution can be discharged merely by 
selectively turning the solute valve shaft 56 by the end tab 85 a quarter 
turn for the tab into latching interference with the fork 87 on the T-head 
52 of the push rod 50. When the push rod 50 is pressed far enough the 
dispensing of solvent or a mixture may be sustained by the latch 58 any 
length of time without manual attention. 
The larger cylindrical portion of the housing 83 opens towards the front of 
the gun where it receives a T-shaped fitting 61 whose inner end valve head 
65 is of the full housing diameter 63 and is rotatable as sealed in the 
mouth 67 of the valve chamber with an O-ring under mild negative gauge 
pressure during operation with the solute suspended from the gun. The 
inner end of the member 61 serves as the cut-off valve seat 92. The outer 
end of the arm 71 serves as a nipple that can be adjustably positioned 
over 180.degree. on either side for the convenient attachment of the 
semi-transparent solute supply hose 72 where the prime of the solute can 
be visually checked at a glance. 
The head end of the passage 73 in the leg portion provides a valve port 75 
where it intersects the arm openings. A rotary valve 77 is mounted in the 
second arm 81 and has an externally exposed screwdriver kerf 85, which 
also serves as an indicator, and a hollow inner end 87 defining an 
L-passage therethrough. A ring element 93 at the inner end journals the 
end so that the lateral opening coacts as a valve with the cylindrical 
concavity of the valve port 75. With this arrangement the T-fitting can be 
displaced 180.degree. for left or right hand operation, and the rotary 
valve 77 is subjected to negative gauge pressure at the port for holding 
it in place. 
PROPORTIONING AND MIXING 
The housing 20 provides a proportioning mixing chamber 98 adjacent to its 
outlet end 80 which receives solvent from the main valve 38 and solute 
through the opening 74 in the side wall thereof. The chamber 98 is molded 
and tapers inwardly slightly. The mixer-proportioner unit 16 received in 
the mixing chamber 98 comprises an outer shell 100 (FIG. 9) whose outside 
surface 102 tapers inwardly slightly from an external flange 104 the same 
as the inner wall of the housing 89 for ready placement and replacement 
therein. The external flange 104 adjacent its outer end which supports a 
resilient seal 106 that engages the outer end 108 of the gun housing as 
held in place by a gland nut 110 threaded at 112 to the outer end 108 of 
the gun housing 20. Adjacent the inner end of the shell an external 
circumferential groove 114 is provided for coincidence with the opening 74 
in the housing wall 20 and has an opening 116 from the groove to the 
interior of the shell 100 for flow of solute to the primary stage of the 
proportioner-mixer assembly 16. Closer to its inner end the shell 100 has 
an external shouldered space 118 receiving an O-ring 120 sealing against 
the escape of any liquid at this point. 
The upstream end of the shell receives an anti-backflow check valve section 
122 on a reduced end portion 124 (FIGS. 3A and 4A). This section comprises 
an axial draw molded body 126 having an enlarged entrance area 128 housing 
a backflow check valve 130 (FIG. 4A) closing against shoulder 132. The 
check valve in turn comprises a collar defining a valve seat 134 and a 
cage 136 telescoping therethrough carrying a resilient valve washer 138 
supported by the rounder face of a retainer 140. Both are assembled on a 
central stud 142 to close against the valve seat to prevent back flow. 
Shoulders 144 on a cage define with the housing 14 a circumferential 
groove that receives a light compression spring 146 which urges the 
closure of the valve. The contents within the mixer are thereby contained 
and prevented from flowing back and possibly causing damage to the gun. 
The inside wall 122 of the shell 100 also tapers inwardly to receive the 
proportioner-mixer assembly of elements press-fitted therein permanently 
in correct orientation. The invention is illustrated with three elements 
collectively providing three interrelated stages permuted from a wide 
selection of defined different mixing zone inlet and outlet port sizes and 
for different but determined output ratios. The upstream element 148 (FIG. 
9) is cored from both ends. The upstream core thereof forms the converging 
wall nozzles 150, 152 and 154 of all three stages and the downstream core 
forms the diverging wall energy converter 156 of the first stage. A saw 
kerf forms the confluence gap or mixing zone 158 therebetween in free 
flowing communication with the opening 74 to introduce the solute. The 
third stage nozzle 154 is axially located; the first stage nozzle 150 and 
the diverging wall energy converter 156 are located laterally thereof on 
one side and the second stage nozzle 152 is divided into several nozzles 
(FIG. 10) located on the other side of and spaced around the third stage 
nozzle 154. 
The intermediate element 160 centrally telescopes over the third stage 
nozzle 154. It provides the second stage mixing zone with diverging wall 
energy converters 160 disposed in alignment with the second stage nozzles 
152 and provides an axial space between the elements which serves 
collectively as an outlet chamber 166 for the first stage confluence 
mixing zones 164 for the second stage nozzles. 
The final stage element 170 provides the diverging wall energy converter 
and mixing zone 172 of the third stage nozzle. It is disposed in axial 
alignment with its nozzle 154 and is spaced therefrom to provide a space 
168 that receives the output from the second stage mixer 162 and supplies 
it as a solute to the confluence zone 174 of the third stage mixer 172. 
In manufacture, the triple mixer-proportioner lends itself for quick 
molding chambers from one set of ratios to another merely by changing pin 
sizes in the cores, or by not using pins to form the nozzle of any one of 
the mixer stages if only a two-stage pump is designed. 
For example, with a two-stage free flowing solute system the relative 
diameters of the port flow areas may be as follows for an overall ratio of 
1:24 and rate of flow at 6 gallons per minute of water as a solvent: 
______________________________________ 
Zone Inlet Port 
Zone Outlet Port 
______________________________________ 
First Stage .0664" .1713" (1-3) 
Second Stage .0885" .2156" (1-8) 
______________________________________ 
Also by way of example, but not limitation, the relative diameters of the 
port flow areas for a free flowing solute system are as follows for an 
overall ratio of 1:64 and rate of flow at 6 gallons per minute of solvent 
at 40 p.s.i.g.: 
______________________________________ 
Zone Inlet Port 
Zone Outlet Port 
______________________________________ 
First Stage (155) .0395 D 
(157) .0527 D (1:4) 
Each of 3 Second Stages 
(163) .0582 D 
(165) .0776 D (1:4) 
Third Stage (173) .1996 D 
(175) .2677 D (1:4) 
______________________________________ 
Rate of flow is related to solvent pressures. The relative sizes of the 
inlet and outlet ports of the stages determine the ratio, their overall 
sizes the rate of flow. Preferably, the first stage is less than 1 to 5 
and if the ultimate ratio is above a 1 to 4 ratio (20% solution) the 
overall system ratio is divided up between the other stages in such a way 
that the first stage ratio resides in that area where there is minimum 
degradation. Thereby a minimized degradation for the overall system is 
attained. This essentially relates the elements of the invention and ultra 
high ratios may be accurately provided. 
The importance of this system is noted when compared with a single stage 1 
to 16 system that might have a degradation of plus or minus 20% for a 
given lift height change because a 20% degradation in the first stage is 
present. By using the two-stage system this is mathematically cut down to 
only plus or minus 5% for the same lift height change. The two stages have 
reduced that which may be tolerable at 20% to 5% variation that is much 
more tolerable. 
For example, if a 1 to 16 system ratio is desired and a single stage 1 to 
16 proportioner is used, any degradation is based upon 1 to 16 and is due 
essentially to solute lift height variation. If a two-stage system is used 
and is divided arbitrarily on a 1 to 4, 1 to 4 basis, which still provides 
1 to 16 overall, the degradation would then be based on that of the first 
stage, a 1 to 4 ratio rather than the overall 1 to 16 ratio. This 
essentially cuts down the degradation of the overall system. Thus, the 
first stage can isolate the following stages with respect to what 
conventionally might be due to solute pressure variation degradation. 
Although the rate of flow of solvent can vary, the flow of solute will also 
vary in a direct relation since the flow speed of the free flowing solute 
is directly molecularly geared and controlled by the solvent by physical 
entrainment in the first mixing chamber. The effective pressures of the 
solvent and solute are substantially atmospheric in the first mixing 
chamber and the kinetic energy of solvent flow imparts a related movement 
of free flowing solute in the ratio determined by the relative spacing and 
sizes of the axially aligned, fixed proportioning flow openings located on 
opposite sides of the first mixing chamber. Effective pressures in 
succeeding mixing chambers are preferably higher according to converging 
wall nozzle designs to maximize the pressure efficiency of the overall 
mixer. 
If the final output pressure is to be soft flow, as in a dispenser, the 
enlarging passage or passsageways need only bring the succeeding mixing 
chambers to atmospheric pressure for a final discharge. If the first 
output pressure is to provide a hard flow from a nozzle, diverging walls 
of the enlarging passages are designed in a well known manner to optimize 
the pressure upon the mixture for use as the solute in the next stage to 
establish higher pressures in succeeding mixing zones as in an applicator. 
It should also be noted that the confluent liquids are directed through 
substantially short cylindrical openings defining the ports having flow 
areas larger than the respective solvent nozzles in the ratios that 
produce the ultimate proportioning desired. The ports need not be 
cylindrical but are more easily produced, have the least surface friction, 
and are more enduring to preserve size against erosion. 
The jetting water molecules freely and fully transfer flow energy in 
proportion to their jet strength to entrain molecules of the solutes in 
the mixing zones and the diverging walls convert energy in relation to the 
differential in the relative sizes of the inlet and outlet ports thereof 
to mix the confluent liquids. 
Where the solute can or does flow freely to a mixer chamber regardless of 
the pressure thereon, there is very little degradation of the mixture 
ratio unless the solute pressure is below the environmental pressure 
(atmospheric) in a mixing chamber, or the pressure upon the mixture 
leaving the last stage drops enough to reflect back upon the mixing 
chamber as where the discharge nozzle is too large. 
In the present invention, contrary to the practice in conventional single 
stage mixer-proportioners, the dispensing opening 176 preferably may be 
equal in flow area to the last stage outlet port, and within substantial 
tolerances can be safely less to improve jet discharge up to but not 
beyond the point where the equalization of solvent and solute mixture 
pressure is disturbed in the zone 174 of the last stage. Accordingly, an 
extension conduit 180 (FIGS. 7 and 8) of reasonable length mountable on 
the gun can be used interchangeably between the mixer proportioner and 
mounted nozzles 12 without disturbing the ratio. 
DISCHARGE NOZZLES AND EXTENDER JOINTS 
The outlet end of the shell 100 of the mixer-proportioner unit 16 extends 
beyond the flange 104 and internally defines a diverging conical tapering 
surface 182 ending in an internal flange 184 of a few thousandths of an 
inch reduced diameter (FIG. 9) and may be considered to be a locking 
flange. The extension, tapering surface and flange 184 may be termed a 
female joint member 188. 
Received within this joint member 188 may be any one of a selection of 
dispensing nozzles 12 or an extender conduit 14 which terminally has a 
corresponding but external taper 190 terminating at the upstream end in 
mating relation with the surface 182 and having an external groove or 
shoulder 192 of a few thousandths of an inch deep. The taper surface 190 
and flange 192 may be termed a male joint member 194 and may be repeated 
intermediate the conduit sections at 194A with corresponding taper and 
flange elements identified with the suffix A. The extender conduit is 
provided with a female joint member 188 at its outlet end and the 
dispensing nozzles are provided with male joint members 194 at their inlet 
ends for interchangeable use on the extender circuit of the 
mixer-proportioner. 
The joint members 188 and 194 have a wall thickness of approximately 1/16" 
thick and frictionally overlap about one inch with a taper of 0.25" in 
12". Their walls are glass smooth as molded from an acetal resin such as 
marketed under the trademark "Delrin" by E. I. duPont de Nemours & Co. 
The overlap provided by these tapers cannot be easily tightened or released 
by relative axial or rotary movement, but with this wall thickness the 
tapers of two mating ends when telescoped can be easily flexed laterally 
back and forth from coaxial alignment in a common plane whereby the joint 
ovates transversely of the plane enough to tighten the contact on one side 
while the contacting surfaces on the other side loosen and slide in their 
engagement in a longitudinal direction under the repeated reversals of 
flexing. The joint tightens or loosens depending on the direction of 
opposing axial forces that are additionally applied to the joint during 
flexing. This planar flexing at the joints enables all parts to be 
properly oriented in proper alignment without any critical adjustment 
conventionally required with threaded or bayonet type joints, there being 
no rotational adjustment required after final assembly even with a tubular 
elbow section being used as one of the conduit elements. Rotational 
orientation can be provided before the joints are tightened. 
If the joints are to be permanent, they can be engaged far enough for the 
flange 192 and groove 184 of each joint to engage, otherwise, short of 
this complete engagement they can be made up and dismantled 
interchangeably at will. 
DISCHARGE NOZZLES 
The discharge nozzles 12 interchangeably associated with the flow areas of 
the mixer proportioners described are of two types, soft flow 12S and hard 
flow 12H. In the soft flow a cylindrical housing 196 (FIG. 8) is provided 
with a male joint member 194 having the converging throat dispensing 
opening 176 with a flow area related to that of the mixer third stage 
outlet port flow area 175 which directs a discharge stream axially through 
a zone 212 against a target 198 (FIG. 6) supported on cross-members 200 at 
the outlet 204 at the end of the housing. The size of the zone 202 in 
length is approximately thirty times the diameter of the nozzle 176, or 
five times the diameter of the inlet housing, or both, and the target 198 
about twice the diameter of the nozzle 176 in FIG. 4A. The stream from the 
nozzle upon start-up splashes radially from the target against the side 
wall 196 with a portion flowing back along the wall progressively 
displacing and replacing air in the space around the jet stream whereupon 
the zone of 202 of the housing goes "liquid solid" in a fraction of a 
second and frictionally engages and directly slows down the jet stream, 
absorbing the kinetic flow energy and discharging the mixture as a soft 
flow through the nozzle outlet openings 204, which with the nozzle outlet 
204 below the surface of the water discharged will not cause any foaming 
or splashing in a bucket or receiving containter. 
The hard flow nozzle 12H is a shorter one and preferably has an 
exchangeable tip 204 to provide the appropriate flow area and rate of flow 
for a jet stream, a fan, or a spray discharge flow having a flow area such 
as 176, coacting with and somewhat smaller than the flow area of the 
proportioning mixer outlet port 175 for mixture ratio accuracy of hot as 
well as cold mixtures. Preferably, a single nozzle body 12H (FIG. 3) is 
provided which interchangeably receives secondary nozzle caps mounted 
coaxial thereon to provide particular cross-sectional flow shapes (FIG. 
3A). 
EXTENSION CONDUIT 
For minimizing the conduit pressure losses and cost of various conventional 
cylindrical flow dispensing conduits to provide assured ratio accuracy, 
the extension conduit 14 of the invention is also a designed structure 
that can be provided either as a single unit or preferably made up of 
several sections for shipping purposes and serve either as a permanent 
unit or a knock-down assembly as related to the joint structure described. 
Each section defines a conduit wall 210 that gradually expands in the 
direction of flow and the connections at opposite ends of each conduit 
comprise correspondingly tapered mating joint elements. 
Accordingly, a preferred embodiment of the invention has been described as 
a complete functioning unitary system with several adaptations for 
proportioning and dispensing a substantially accurate mixture ratio hot or 
cold, over a wide range of solvent pressures including a multi-stage mixer 
having a mathematical relationship relating the overall degradation in 
ratio, if any, to that of the first stage with minimum variation of solute 
pressure approximating zero gauge pressure and an ultimate loss of solute 
pressure less than 10%.