U.S. patent number 3,863,843 [Application Number 05/460,889] was granted by the patent office on 1975-02-04 for anti-back siphoning water supply valve and mixer.
Invention is credited to Valentine Hechler, IV.
United States Patent |
3,863,843 |
Hechler, IV |
February 4, 1975 |
ANTI-BACK SIPHONING WATER SUPPLY VALVE AND MIXER
Abstract
A low cost portable mixer-dispenser device connectable to a
garden hose and supplied with potable water from a municipal water
dispensing system in which a non-contamination safety back flow
check valve located at the inlet of a water chamber along with a
vent valve therebeyond coacts therewith to vent the chamber to
atmosphere at a point upstream of a solution mixing chamber. A
manual dispensing valve is located at the outlet of the water
chamber and the closure and venting of the water chamber occurs
when the pressure on the municipal water supply drops to a
predetermined low gauge pressure below which maximum degradation of
the dilution ratio of the solution is not tolerable for an
aspirating jet pump that is located between the manual valve and a
dispensing nozzle, thereby serving a dual function of protecting
the supply system against contamination and preventing operation if
water pressure becomes inadequate to maintain in a proper mixture
ratio.
Inventors: |
Hechler, IV; Valentine
(Northfield, IL) |
Family
ID: |
26988662 |
Appl.
No.: |
05/460,889 |
Filed: |
April 15, 1974 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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333309 |
Feb 16, 1973 |
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Current U.S.
Class: |
239/318;
239/416.1; 239/335 |
Current CPC
Class: |
B05B
7/30 (20130101); E03C 1/046 (20130101); E03C
1/108 (20130101); B05B 7/2443 (20130101); B29B
7/7438 (20130101); E03C 1/104 (20130101); Y02A
20/20 (20180101) |
Current International
Class: |
E03C
1/04 (20060101); E03C 1/10 (20060101); E03C
1/046 (20060101); B05B 7/30 (20060101); B05B
7/24 (20060101); B29B 7/00 (20060101); B29B
7/74 (20060101); B05b 007/30 () |
Field of
Search: |
;239/414,415,416.1,433,310,311,318,335X,347,348,583
;222/547,544 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: King; Lloyd L.
Attorney, Agent or Firm: Harbaugh and Thomas
Parent Case Text
This is a continuation, of Application Ser. No. 333,309 filed Feb.
16, 1973, now abandoned.
Claims
What is claimed is:
1. In a safety device for potable water supply and dispensing
system having a manually valved outlet;
a housing defining a flow compartment connected releasably to the
outlet and having an inlet port, an outlet dispensing means having
a flow area open to atmosphere substantially less than the flow
area of the compartment, a valve port opening to atmosphere
disposed intermediate the inlet port and the outlet dispensing
means, and mixing means between said valve port and outlet
dispensing means;
an inlet valve closing the inlet port against the inflow of potable
water to the inlet port;
a vent valve in communication with said valve port opening to vent
the compartment to atmospheric pressure;
means for coordinating said valves to open one while closing the
other; and
resilient means under pressure coacting with the coordinating means
to activate said inlet valve to close said inlet port when the
opening force of supply water upon the inlet valve and the closing
forces of water pressure in said compartment upon the vent valve
drops to a predetermined positive gauge pressure.
2. The device defined in claim 1 in which said resilient means
activates said inlet valve to close when the combined atmospheric
pressure on the vent valve and the resilient means urging the vent
valve to open exceeds the positive gauge opening pressure of the
water supply upon the inlet valve.
3. The device defined in claim 1 in which said resilient means
closes said inlet valve when the closing pressures upon the inlet
valve of the resilient means and the pressure in the compartment
exceeds the opening pressure upon the inlet valve.
4. In a device of the class described, the combination of a housing
including an inlet element connectable to a pressurized potable
water supply outlet and having a passage therethrough;
safety valve means for controlling the flow of water through the
passage;
a jet pump in said passage including an energy converting nozzle
with converging walls to convert water pressure to energy;
a mixing chamber of appreciably larger flow area than the nozzle
disposed in axial alignment therewith;
means for laterally supplying a liquid to said mixing chamber
whereby said water exchanges energy with and entrains said liquid
to form a solution;
a dispensing nozzle connected to said jet pump having an outlet
orifice with a flow area appreciably less than the flow area of
said valve means; and
means responsive to the pressure of said water upstream of said jet
pump for closing said valve means and venting said passage to
atmosphere when the pressure upon said water drops to a
predetermined gauge pressure.
5. The device in claim 4 in which said valve means and valve
element are slide valves closing cylindrical ports.
6. The device defined in claim 5 in which the slide valves and
ports have substantially the same areas exposed to the pressure in
said passage.
7. The device defined in claim 4 in which said jet pump in said
mixing chamber establishes in operation a back pressure in the
passage upon the valve means.
8. The device defined in claim 7 in which the inlet pressure and
compartment pressure vary proportionately and said resilient
pressure is a varying pressure diminishing with closure movement of
the inlet valve.
9. The device defined in claim 7 in which the back pressure upon
the valve means is dropped to atmospheric pressure by the opening
of said vent valve immediately following the initial closure of the
valve means.
10. The device defined in claim 4 including a valve element opening
said passage to atmosphere and in which said pressure responsive
means includes a resilient element urging the closing of said valve
means and opening of said valve element.
11. The device defined in claim 4 in which the differential in size
between said jet pump nozzle and the energy exchange chamber
determines the proportioning ratio between the water and entrained
liquid above said predetermined gauge pressure.
12. The device for use at the dispensing end of a watering hose
having a resilient wall expansible under water pressure;
a housing secured to the dispensing end having a compartment
passage therethrough to a dispensing end and a lateral opening in
communication with the atmosphere;
flow conducting discharge including a nozzle means connected to
said dispensing end;
an inlet valve adjacent said end opening with the flow of water
under pressure into said compartment;
a vent valve closing said lateral opening under said pressure in
the compartment;
means urging closure of said inlet valve at a predetermined low
gauge pressure;
means interengaging said inlet valve and vent valve to open said
vent valve upon closing of said inlet valve; and
aspirating means in said compartment adjacent to the discharge
means actuated by the flow of water through said compartment above
said predetermined gauge pressure upon the water.
13. The device defined in claim 12 in which water pressure in said
compartment upstream to said aspirating means exerts an opening
pressure upon the inlet valve substantially equal to its closing
pressure exerted upon said vent valve when closed, said vent valve
being directly exposed to the path of flow of water through the
compartment.
14. The device defined in claim 12 in which said discharge means
and said dispensing end having an unconventional thread thereon for
interchange of specific discharge means that are continuously open
to atmosphere.
15. In a device of the class described the combination of a housing
defining a water chamber having a water inlet connectable to a
pressurized potable water supply and an outlet;
a manual valve controlling outflow of water under pressure through
said outlet;
a back flow check valve opening said inlet in response to a
predetermined rise in pressure differentials between the chamber
and water supply pressure when the manual valve is closed;
means for venting the chamber directly to atmosphere when the
pressure in the chamber drops to a predetermined low gauge pressure
and the manual valve is open;
a solution mixing means having a chamber open to atmosphere at all
times comprising;
a jet pump for aspirating a chemical concentrate into said housing
and mixing it with water flowing through the manual valve in proper
proportion; and
nozzle means having a restricted orifice for dispensing said
mixture to atmosphere;
said predetermined gauge pressure being a pressure below which
maximum degradation of the dilution ratio of the solution is not
tolerable for dispensing purposes.
16. The device defined in claim 15 including a nozzle having a
restricted orifice opening to atmosphere in communication with the
manual valve outlet;
said manual valve being disposed in the chamber space between said
check valve and the vent valve.
17. A device of the class described comprising an elongated housing
having a wall with an inwardly offset wall portion between a water
chamber and a mixing chamber including an axial flange defining a
vent valve port and a cylindrical main valve port interconnecting
the two chambers;
a flanged sleeve means at the inlet of the water receiving chamber
defining a cylindrical inlet port;
reciprocating valve members slidably received in said ports;
means interconnecting the vent port valve member and the inlet port
valve member for coaction in which one valve is closed while the
other is opening with momentary overlappig of their closing
movement;
resilient means interengaging the inlet port valve and main port
valve urging the closure of both and the opening of the vent port
valve;
a jet pump in the mixing chamber, said water chamber being open
continuously to atmosphere through jet pump when said main port
valve is open;
said jet pump including a converging energy converter, and a
diverging energy converter with an energy transfer chamber between
them; and
a nozzle mounted on the outlet end of the housing.
Description
BACKGROUND OF THE INVENTION
In increasing numbers of states, anti-back siphoning devices must
be installed at a valve outlet of a potable water distribution
system if the valve outlet level from which the water will flow is
not above a potential flood level. This requirement in the codes of
a few states generally operates to protect the rest of the states
on nationally merchandised products. Where valves are used in such
devices the performance test generally employed for acceptable
protection involves placing a 0.050 inch wire in all check valves
which are in the path of reverse flow, if there is no adequate
vacuum breaker per se, in the pure water line leading from the
valve outlet. Most valve devices fail and very few, if any, have
passed this test.
Although fertilizers and pest control chemicals can be sprayed into
open air without a vacuum breaker but with only a constantly open
minimum air gap siphon sprayer at the outlet end of a hose, the
handling of the chemical supply along with the nozzle is a
deterrent and critical proportioning deficiencies and
irregularities are involved.
Vacuum breakers, required in an endeavor to prevent back-flow
contamination of a municipal potable water system, one sometimes
used with dilution mixing-dispensing devices located at the end of
a garden hose that utilize both the water and its pressure to mix
and dispense fertilizer or pest control solutions. As the
designation vacuum implies, however, a back flow stops flow and
vents to atmosphere when the municipal water supply drops to zero
pounds gauge pressure. Contaminating flow back into the municipal
supply line may or may not occur.
On the other hand, vacuum breakers are generally located upstream
well ahead of flow control valves so that theoretically there can
be no backflow of solution into the municipal supply. However, some
mixtures may have already moved back past the check valve before a
vacuum gauge pressure occurs or the vacuum breaker operates. Other
vacuum breakers are made of an elastomer that can deteriorate and
permit dangerous leakage even with the potable water open to
atmosphere.
SUMMARY OF PRESENT INVENTION
A safety back flow cut-off valve, preferably a slide valve, is
located where the potable water enters a potable water chamber
whose supply outlet to the mixing chamber is controlled preferably
by a two-state manually opened and closed valve. A vent valve
between the two valves opens the chamber to atmosphere to drop the
chamber pressure to atmospheric pressure when opened. The cut-off
valve is urged to its closed position by a spring exerting an
effort in the range of 3 to 10 pounds and the venting valve is
coupled therewith to open immediately following initial closure of
the cut-off valve.
With this arrangement a unitized gun type device can be provided to
mix and dispense a mixture which includes a safety back flow check
valve, a flow control valve, mixing chamber and dispensing nozzle.
The gun is connected to the outlet of a potable water supply hose
and a predetermined ratio solution is produced and dispensed under
a minimum loss of water supply pressure yet, as a matter of safety,
the flow of water and venting of the potable water chamber to
atmosphere can sequentially be made when the water gauge pressure
drops too low to provide a dilution ratio. This is accomplished
regardless of whether or not the pressure may drop further to a
point where back-siphoning might otherwise occur. A further
safeguard is present wherein the volume of water under pressure in
the supply hose continues a positive flow of a hydraulically solid
supply to provide a time interval within which the safety
components can be activated to avoid danger before it occurs. For
instance a 150 foot garden hose subjected to 70 p.s.i.g. stores
approximately one half gallon of water to provide an operational
time lapse for valve actuation before a flow back potential is
reached.
The gun serves as a carrying member and a nozzle-directing handle
with a concentrate bottle flexibly hung thereto without burdening
the movement of the handle for spray purposes other than to support
the dead weight of the bottle. This support is a close distance of
a few inches so that the gun never gets below the bottle contents
when set down. Further, the lift height of the concentrate is
negligible and insignificant within ounces for the concentrate
because it is aspirated only a short height directly to the jet
pump concentrate inlet.
The jet pump preferably is a two-state jet pump in which converging
walls leading to a jet nozzle converts pressure on the water to jet
flow energy and the jet is directed into a mixing chamber having a
larger flow area than the nozzle where water molecules transfer
energy to and entrain molecules of the solution in relation to the
differential in sizes to provide a predetermined proportioning
ratio and then passing the mixture through expanding walls to
convert the energy back to pressure for dispensing through a
dispensing nozzle having a flow area substantially less than the
water flow area ahead of the jet pump where the water is above a
predetermined low pressure.
With great efficiency a substantially constant dilution ratio can
be provided with jet pumps in tandem as where the first stage ratio
is 1 to 5 and the output of this is supplied to the second stage at
a ratio of 1 to 5 to provide a 1 - 25 dispensing solution. This
ratio can be maintained rather accurately over the expected range
of municipal water pressures, particularly with the supply solution
close to the level of the gun.
Moreover, with a ball check in the diverging walls of the first
stage to protect against any drain of diluted flow back to the
concentrate supply and to maintain priming, any back-flow tendency
that may be residual in the compartment will be negligible for the
mixture remaining in the co,partment because below a certain
working water supply pressure the aspirating effect will decline to
a negligible gauge pressure well before the water supply pressure
drops to zero gauge. Then with the first stage mixing chamber
closed any back flow at atmospheric pressure through the first
stage before zero gauge is reached is prevented. Accordingly, for
plural advantages, the safety factor can be related to a critical
low water pressure. The safety cut-off for everything can be
resolved at the lowest pressure flow for acceptable proportioning
of the jet pump mixer. Thereby any potable water pressure below a
desired mixing efficiency will not be permitted to continue to
flow. This is accomplished by a positive closure of the inlet
valve. With this shut-off action of the inlet valve the water
chamber is vented to atmosphere while there is still inlet pressure
in the potable water supply hose that would prevent back flow into
the hose at atmospheric pressure even if there is possible leakage
at the closed inlet valve, and back flow of diluted solution in the
concentrate supply will be inhibited.
IN THE DRAWINGS
FIG. 1 is a perspective view of the device embodying the invention
as manipulated in use and operation;
FIG. 2 is a longitudinal section through the gun-handle portion of
equipment shown in FIG. 1;
FIG. 3 is an enlargement of the valve portion of the sectional view
of FIG. 2 with the valves disposed in full liquid flow
positions;
FIG. 4 is a view similar to FIG. 3 in which the valves are in full
no-flow positions;
FIG. 5 is a view similar to FIGS. 3 and 4 in which the valves are
at an intermediate stage of operation;
FIG. 6 is a section taken on lines 6--6 in FIG. 2;
FIG. 7 is a section taken on line 7--7 in FIG. 2; and
FIG. 8 is a view similar to FIG. 3 showing a simplified
modification of the dual flow and the dual action vent valves.
DESCRIPTION OF A PREFERRED EMBODIMENT
Referring now to FIG. 1 in further detail, a unitary housing 10
molded of a plastic is shown having an elongated compartment 11
therethrough with its inlet end 12 comprising a coarsely threaded
3/4 inch opening 14 receiving the outlet fitting 16 of a garden
hose 17 whose end 18 seals against a washer 20 having the marginal
edge 19 of a screen member 21 embedded therein supported by a
flanged insert 22, engaging a housing shoulder 24. The outlet end
26 of the housing is externally threaded with an unconventional
thread 28 which prevents standard water garden connections used
with gardening equipment being reversely or improperly made. Only
an intended outlet fitting such as a spray nozzle 30 can be
attached that is open continuously for discharge to atmosphere as
at 31.
Spaced from its inlet end 12 the compartment 11 is internally
provided with an axial circular flange 32 (FIG. 3) extending
towards the inlet 14 and concentric with and radially spaced from
the interior wall 33 of the housing to define a ring valve port 34
terminating in radial apertures 35 open to atmosphere.
The flanged insert 22 internally defines a cylindrical port 36 of
an inlet slide valve 37 construction having a spider 38 at its
inlet supporting a valve guide 40 having a head 42 thereon
supporting an almost fully compressed long compression spring 44 at
one of its ends whereby its effort at the other end varies very
little with its working movement. A U-shaped V-ring valve 46 is
reciprocably mounted on the guide 40 with the inner wall 48 thereof
sliding in sealed relation on the guide 40 while the outer wall 49
slidably engages the cylindrical wall of the port 36.
A semi-conical cup-shaped valve member 52 having flow openings 54
in its walls 56 has its base 58 reciprocably mounted also on the
guide 40 where, on its outer side, it supports the edges of the
seal 46 with its bottom directed towards the inlet 14 while on its
inner side it engages the other end of the compression spring 44
for it to urge the closure of the inlet valve 46. The rim 47 of the
valve member 52 is continuous and circular to receive in adhered
relation an elastomer V-ring 60 thereon internally of its bight in
a position so that the spread walls 61 thereof slidably engage as a
valve member 63 the walls 33 and 62 of the ring valve port 34.
As shown in the sequence steps of FIGS. 3-5, the wall 56 serves to
direct substantial flow of water from the inlet port 36 against the
valve member 63 and its length is such that when the inlet valve 46
is closed, resting against the spider 38, the vent valve member 63
is fully open; and when the vent valve member 63 is fully closed as
when engaging the wall 62 beyond the vent openings 35, the inlet
valve 46 is wide open. The spacing of the entrance edges of the
inlet and vent ports in relation to the length of the wall 56 is
such that the inlet valve 46 begins to seal the inlet port 36
before the vent valve 63 begins to open so that in their concerted
coacting movement preferably momentarily both valves are closed at
the same time during their transition.
It is preferred also that the inlet and vent ports 36 and 34
substantially have the same flow area and the spring 44 exerts a
valve closing effect from three to five pounds, but, if there is
substantial differential it would be with the vent area being the
larger for stable conditions. Thereby, with the inlet valve 46
closed and atmospheric pressure present in the compartment 11 the
inlet valve will not open until the inlet pressure opens the inlet
valve 46 and in doing so initiates closure of the vent valve 63.
Thereafter, with no outlet from the comparment open to atmosphere,
the pressure upon the vent valve 63 will drive it to its fully
closed position and will thereby overcome any tendency of the inlet
valve to be drawn back against a full opening by virtue of the
reduced pressure of the high rate of flow passing between the valve
and the seat. The spring then supplies the means for urging the
inlet valve to close when pressure in the compartment drops below a
predetermined pressure. Until then the vent valve holds the inlet
valve fully open for full flow operation. In fact, given
substantially equal pressures on opposite sides of the inlet valve,
the inlet valve 46 is held open by the pressure differential across
the vent valve 63. Then as water inlet pressure happens to decrease
to a predetermined gauge pressure the opening of the vent valve and
closure of the inlet valve can be accomplished by the spring
44.
The vent valve 63 thereby serves as a safety pressure relief to
atmosphere when the compartment pressure drops enough for the
spring 44 to initiate closure of the inlet valve 46 and therewith
initiate the opening of the vent valve 63 while gauge pressure
still exists in the inlet compartment. Atmospheric pressure is then
sure to take over and prevail in the compartment 11 while some
gauge pressure still exists at the inlet valve and the inlet valve
46 is further closed to the extent urged by the spring against the
decreasing inlet pressure.
As the input pressure varies, so long as the force developed by
pressure against the vent valve exceeds that of the spring force,
the inlet valve will remain fully open.
As the pressure diminishes to a point less than the force exerted
by the spring, the spring 44 sequentially closes the inlet valve
and opens the vent valve. This closing pressure can be
predetermined and is at a positive gauge pressure and preferably
above that which would be reached at or shortly before the
municipal water pressure and flow drops to a point that is
inadequate to provide acceptable aspiration of the concentrate and
proper proportioning of the mixture of liquids in the mixing
chamber as herein described.
Manual control of the flow of water through the compartment is
provided by a dual valve arrangement having a low opening effort
followed by equalization and a final low effort full opening. Thus,
a partial flow, full flow or no-flow operation well within the
thumb strength of a housewife is provided to assure adequate
working action of a pump jet syphoning device that provides a
desired amount of different solutions of proper proportions for
various tasks including cleaning detergents.
For this purpose the inside wall of the cylindrical flanged member
32 internally provides a large cylindrical port 70 (FIGS. 4-6)
which receives a radially vaned guide 72 carrying a flanged valve
sleeve member 74 supporting a V-ring valve seal member 76 thereon
with the edges of the sides 78 of the seal resting against the
radial flange 80, to close it as guided by the vanes 72.
The inside face 82 of the wall 84 of the flanged member 32 also
provides a cylindrical port 86 with which a smaller area valve 88
cooperates sequentially with the larger area valve member 76. The
smaller valve member 88 is preferable an integral part of a single
molding which includes the radial guide vanes 72 reduced in their
radial dimension at 90 to radially and axially support the sleeve
member 74 loosely with a lost motion relationship on the integral
stem 92 which in turn terminates forwardly in the smaller valve
head 88 having a circumferential groove around it also receiving a
V-ring or an O-ring valve seal 94. An O-ring may provide some
frictional effect to assist in closing the larger valve. The inner
end 96 of the stem 92 reciprocably extends in an axial direction
through an opening 97 (FIG. 1) in a cross wall portion 98 of the
housing having a molded cup shape 100 carrying a V-ring 102 seal
therein which seals the stem as exposed to atmosphere at its inner
end in a recess 110.
In the assembly of the two valves 74 and 88, the stem 96 has the
V-ring 102 slipped thereon with the sides of the V-ring disposed
towards the valve head 88 and the flanged member 74 in place
against the ends 90 of the vanes 72. Thereupon the seal ring 94 is
installed and the assembly slipped into its working position as
shown in FIG. 3 and then pushed home to the position shown in FIG.
4 with the vanes 72 seating the seal 102.
In operation, the dual valve manually opens sequentially. The stem
96 is moved towards the inlet 14 to open the small valve 88 against
water pressure in the compartment 11, only nominal effort being
required due to the smallness of the valve area exposed to the
pressure. Upon its opening and water flow the pressures are
essentially equalized on both sides of the larger valve 76
whereupon it can be easily moved manually to its wide open position
by continued movement of the valve stem. Thereafter the valves can
be held open manually with little sustained effort and when
released the pressure upon the stem 92 at the seal 102, even at low
pressures is enough to urge closure of the valves when manually
released.
Referring to FIG. 8 a modification is shown in which a "feel" of
opening the larger valve 74 is assured by eliminating the valve
guide 40 and spacer 43 of FIG. 4 and extending the spring 44. The
extended spring 44A is much longer and is of such initial length
that its change of effort in its working length is greatly
minimized to provide an action equivalent to that performed by the
spring 44 in FIG. 4 when both valves 44 and 76 are wide open.
The small valve 88 is integrally formed with an elongated guide rod
which also serves as a push rod 92A which is slidably supported at
its opposite ends. The inlet end is slidable in a spider 38A and
its other end is slidably supported on the housing for manual
actuation as later described. The cup member 52A is slidably
mounted upon the rod 92A at its inlet end with the V-ring seal 46
carried on the end wall 58 thereof.
The wall 56A of the cup member 52A is longitudinally slotted and
elements thereby formed adjacent each slit 50 are alternately
offset radially inwardly and outwardly to provide radially spaced
longitudinal guides 53 and 55. Otherwise, the cup 52A if molded can
be molded to the shape shown. The guides 55 slidably engage the
inner wall 33 of the housing 10 in guided relation while the inner
guides 53 guide the flange member 74A modified to carry a
cylindrical flange 57 to be slidably guided by the inner guides 53
in its excursion. The guides 53 also prevent the spring 44A from
buckling. The spaces 64 made at the slits 50 by the radially spaced
guides provide full flow openings 54. The spider in this instance
slidably supports the push rod 92A and the screen 21A is arched to
accommodate the excursion of the push rod 92A.
In this embodiment the push rod 92A is initially of uniform
diameter throughout and machined to provide spaced circumferential
grooves 150 receiving segmented C-spring 152 washers supporting a
V-ring seal 94A between them cooperating with the cylindrical port
82 as supported concentrically by a third C-spider spring 154
received in a third circumferential groove 156 and provided with
diverging radiating fingers 83 terminally notched to engage the
downstream edge of the wall of the cylindrical port with flow
openings between them. In doing this each finger 83 preferably is
quarter turned to present itself edgewise to the flow of water
through the valve port 82 and the notch can be made in the stamping
of the fingers. Preferably the shaft can be relieved without loss
of necessary beam strength where it passes through the port 82 for
assured full flow of water therethrough.
For manual actuation of the valves a longitudinal channel 104 is
formed in the wall of the housing 10, has a narrow opening 101
(FIG. 6) with convergingly tapered walls 107, to laterally receive
a push rod 106 that is pressed in a radial direction and snapped
into longitudinal sliding supported relation with its L-shaped end
108 reciprocably received in a recess 110 molded for that purpose
ahead of the wall 98. The front end of the push rod is reversely
formed to provide a thumb handle 112 which transmits actuating
pressure in a direction holding the rod 106 in the channel 104. The
inner end 114 of the L-shaped portion 108 engages the end of the
valve stem 96 or push rod 92A. The full flow passage 116 from the
valves is U-shaped as indicated in FIG. 5 around the recess 110 to
the forward part of the compartment which removably receives dual
mix jet pumps operating in tandem.
The arrangement of the jet pumps 111 and 113 is within a unitizing
shell 115 for ready change for different chemicals and proportions.
The exterior closely follows the substantially cylindrical
compartment 118 area in the housing as sealed at opposite ends with
respect thereto by O-rings 117 to provide a minimized space or
reservoir 107 for a chemical concentrate. The inlet to the jet
pumps for the water is at 109 and the concentrate is aspirated to
the concentrate compartment 118 through the depending nipple 103
from a concentrate bottle 130 by a disconnectable flexible hose 138
and dip tube 140 that minimize the height of the lift for the
concentrate.
Each pump includes a tapering converging throat 136 spaced a short
distance from a mixing chamber 137 to provide a gap 105 that leads
through diverging walls 139 to the outlet end 26 of the housing
10.
The second stage jet pump 111 extends the length of the housing
compartment and is off-set radially an appreciable distance from
the axis thereof to accommodate other elements. Along the side of
the converging throat 136A of jet pump 111 is the primary jet pump
113 with a converging entrance 121 for water, a jet gap 105A for
concentrate and a mixing chamber 137A with diverging walls 139A.
The gap 105A of the primary jet pump is in communication with the
space 118 to aspirate concentrate and the outlet of its mixing
chamber is in communication with the throat of the gap 105B of the
secondary jet pump 113. A first dilution proportioning is
accomplished in the first jet and the final mixture proportioning
is accomplished in the second stage, thereby providing a high
degree of constancy and accuracy above 10 p.s.i.g. of water
pressure. A ball 135 is disposed at the outlet of the primary jet
pump where it normally resides in a cavity 133 during operation but
enters the tapered space 123 is guided by cage pins 141 to serve as
a back flow check valve if there is any tendency for back flow of
mixture through the primary jet pump 113.
Thereby the concentrate is diluted and mixed with one proportion,
and that mixture further diluted and mixed for discharge at the
outlet of the housing. The action of the jet pumps provide a quite
accurately proportional mixture for dispensing through a fixed but
interchangeable, spray nozzle on the front end for operation at
water pressures which generally are well above approximately 5
p.s.i.g. Below this pressure the spring 44 is set to actuate the
valves 46 and 63 as for the antiback-flow purposes already
described. The nozzle can be rotated as sealed by an O-ring 63 when
held by a flange nut 65 threaded as already mentioned to a
non-conventional thread 28.
For the purpose of assisting the constancy of the mixture ratio a
depending stud 120 is provided which is cross kerfed at 122 and
apertured at 124 to receive the free end of a flexible looped
hanger strap 126 secured thereto by a grommet 127. The strap at its
free ends has a snap fastener 128 for receiving and supporting a
conventional bottle 130 or container of concentrate solution by and
close to the handle 132.
The hanger 126 releasably engages the handle 132 of the bottle in
supporting relationship and on the nipple 103 leading to the
chamber 107, a flexible tube 138 of fixed length is connected
between the nipple and a dip tube 140 in the bottle 130.
As shown in FIG. 1, the assembly is manipulated by one hand, either
right or left, with the fingers around the housing 10 used as a
handle and the thumb is disposed in place to operate the flow valve
push rod 106. With the flexible hose 17, hanger 126 and tube 138, a
person can manipulate, aim and direct the spray 142 in any
direction without moving the bottle other than conveniently to
carry it with the operator as the operator moves from place to
place.
Ease of cleaning, servicing, storing and the use of the device are
apparent from the description set forth in the preferred embodiment
and the Summary of the Invention.
The phrase "gauge pressure" employed herein means a pressure above
atmospheric pressure sometimes specifically referred to as positive
gauge pressure.
From the drawings the description relating thereto and the appended
claims, it will be appreciated that a jet pump having two or more
stages provides for better accuracy and control of the dilution
ratios as well as an extended range of such ratios with respect to
variations in water supply pressures; the energy transfer process
never creates any negative pressure than is needed to draw the
concentrate into the device and the variation of ratio with
pressure changes is negligible over a wide range of input
pressures; the use of the diverging energy converter provides
pressurized output capable of an exceptionally good swirl-nozzle
spray pattern; wide open energy transfer chambers along with full
flow large tubing and fittings are not easily clogged by wettable
powders nor unduly restrictive to the passage of viscous
concentrates; and the very high turbulence created by the energy
transfer process within the energy converters assures homogenous
blending of the output spray solution.
Accordingly, the advantages of the spray device are:
a. Maintenance of a practically constant dilution ratio regardless
of variations in input pressure;
b. Wide specification limits are provided for water pressures from
10 to 100 p.s.i.g. and water temperatures as high as the material
of the parts will permit, with the preferred materials used being
polypropylene or the like, anodized aluminum, and synthetic seal
materials.
c. Quick change construction of matched jet pump and nozzle enable
1 to 7 gallons per minute dispensing; mixture ratios up to 20:1
with a single stage jet pump and up to 200:1 with two stage jet
pumps; any cone spray up to 30.degree. and utilize a mixture of any
viscosity concentrate capable of flowing.
d. A thumb operated hydraulically powered valve for instant and
exact control of two different flow rates;
e. Automatic flow cut-off whenever input pressure is insufficient
for satisfactory operation;
f. Extra large concentrate tubing and ports;
g. A slim-line gun dispenser that is easy to grip with a balanced
hing like suspension of concentrate container below for short
lift;
h. Corrosion resistant construction throughout;
i. Larger mouth, one-gallon container with open mouth or vented cap
can be used for suspension including original shipping containers
with concentrate already in them;
j. Extra large valve ports assure insignificant pressure loss
through valves up to 7.5 gal. per min. flow with a housing
approximately one inch in diameter.
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