CA1044664A - Purgeable dispensing gun for polyurethane foam and the like - Google Patents

Purgeable dispensing gun for polyurethane foam and the like

Info

Publication number
CA1044664A
CA1044664A CA249,532A CA249532A CA1044664A CA 1044664 A CA1044664 A CA 1044664A CA 249532 A CA249532 A CA 249532A CA 1044664 A CA1044664 A CA 1044664A
Authority
CA
Canada
Prior art keywords
gun
housing
fluid
quill
product
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA249,532A
Other languages
French (fr)
Inventor
William R. Brooks
Irving C. Heinzel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US05/591,174 external-priority patent/US4117551A/en
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of CA1044664A publication Critical patent/CA1044664A/en
Expired legal-status Critical Current

Links

Abstract

PURGEABLE DISPENSING GUN FOR
POLYURETHANE FOAM AND THE LIKE

Abstract of the Disclosure A gun is disclosed for mixing and dispensing a settable fluid product having separately stored constituents. The gun has primary valves for controlling the flow of product fluid constituents along separate primary paths and into a common mixing and dispensing nozzle. A secondary valve permits the flow of a purge fluid along secondary passages, past the primary valves, along at least parts of the primary passages and through the nozzle. According to an important aspect of the invention, a disposable nozzle is arranged with separate, independently operable valves contained therein for isolating the interaction of the product constituents to the nozzle.

Description

Back~round of the Invention This invention relates generally to apparatus for mixing and dispensing multi-component foam or like fluid pro-ducts, and relates.more particularly to purgeable spray guns for urethane foam.

The use of sprayed urethane foams is rapidly expanding in construction, .insulation and packaging industries. This 20 relatively inexpensive product has proved to be a highly valu- .
able insulating and packaging material for a number of reasons.
Its resiliency, high compressive strength and its excellent dimensional stability make it an excellent packing material for shipping relatively fragile items in cartons where rough .

., . i . . . . `

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, 4~64 ~ ~
handling may be encountered.~ It has extremely low heat-trans- ~ -mitting properties, making it an excellent insulation material.
Relatively extreme temperatures do not greatly affect it. It ~ -~
does not deteriorate rapidly, thus providing a long service life. `
Further, urethane foam can be easily prepared and ~ -.; . ., then applied or emplaced in an almost limitless variety of de-sired locations. The several fluid components of urethane foam ; ~ -are often stored separately, and then are mixed on the job site to create the foaming product. This mixed, foaming product is ~ -10 then discharged or sprayed into a desired location or target ;
area. After application, the foam hardens into a light, strong protective and insulative covering. Devices which have been ~used with great success in mixing and applying urethane foam aro disclosed n Brooks U.S. Patents 3,559,890 and 3,633,795.
Experience has shown that the components of urethane foam;can be selected so as to provide a relatively quick-;hardening~product fluid. After the material is sprayed on `~
or into the target area, foam product solidification begins.
Now,~ this solidification occurs not only in the desired target ~20 ~area, but~in~residue product which may remain within~the dis-pénsing~gun~after~spraying has~been stopped. Residue foam product which has hardened inside parts of the gun make gun ;`
cleansing~and~subsequent use difficult. This problem has been met with great succèss by foam dispensing guns such as those ,~~, . ~ -. .
disclosed in Brooks U.S. Patents 3,633,795 and 3,784,110. In these devices, the foam gun i8 provided with a nozzle inside which the foam product constituents are mixed, and from which - ~ 2 -~ 4 the mixed foam product is dispensed. After gun use, the nozzle can be removed, and a fresh nozzle installed.
Recently, the use of urethane foam as an insulation and packing material has found increased favor in applications providing target areas of restricted size and shape. When 1 -workèrs are dealing with such restricted target areas, they often find it necessary to spray or app-ly the foam in an inter~

mittent manner. For example, a layer of foam may be initially ;.
applied to the restricted target area, and then foam spraying is halted while the worker inspects the target area; after ~, . .
inspection, another foam layer is applied. In another case, the worker may be forced to temporarily halt foam spraying while either he or a co-worker place an object to be shipped !:
within a carton or other container. After object emplacement, foam applying operations can be resumed. As the container is filled, spraying operations may necessarily again be halted ¦~`
while inspection of the finished packing operation is under-taken. The carton is then closed, is removed, and a new empty carton is placed at the work station for spraying and packing. ¦~
~20 Under such circumstances, it may be inconvenient to re ve and replace a spray gun nozzle after each short spraying ¦

` operation. A number of short spraying operations may be re-.
quired during a single packaging or insulating job, and repeated .
nozzle replacement can add to costs, and can delay production.
While relatively short time lapses between sprayings can,under some circumstances, be tolerated without foam set-up .

lQ4~i6~ . I
and gun cloggin~, time lapses of greater duration permit the -;

fluid constituents to either completely or partially solidify 1~''" ~' ' ' ~
within the gun components, thereby completely or partially clogging the gun. Poor gun performance and an insulation or ¦
packing job of degraded quality result. Worker annoyance and hurried efforts can also occur, and can indirectly contribute to a finished product of less than maximum quality. i`
This problem of partial gun clogging during inter~
mittent spraying operations can be minimized or eliminated by ¦- ~
10 purging those parts of the gun wherein the fluid components are ¦- -comingled, mixed and discharged with a nonreactive purge fluid. A
..~, .

gun of this general type i~ shown in U.S. Patent 2,991,015 to Standlick. In addition, purging the gun permits use of fluid ~ . .
components which form a relatively fast-setting product not prac- ~.
tically accommodated in other types of guns or dispensing systems. l~
It is an object of the present invention to provide an improved dispensing gun for mixing and discharging fluids ;
~sùch as urethane foam. !i.
Another objec-t is to provide a fluid mixing and dis-~20 pensing gun wherein the problem of fluid solidification within the gun can be economically minimized or obviated even when the ii gun is used intermittently during short, spaced apart periods.
:..
I ~ Yet another ob3ect is to provide a spray gun which . ~ .
permits purging settable product fluid constituents from important gun parts. ~ -.,...~ .
Still another object of the invention is to provide ~-~

a dispensing and spraying gun for polyurethane foam and like 1' ~ ' _ 4 _ I :, . .
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. .
products wherein relatively complete purging of both the nozzle and relatively upstream gun portions i8 assured. A more specific object is to-provide a dispensing gun for urethane foam and like ', fluids wherein the fluid components and product can be easily ~ ~' and quickly purged from gun valves, the mixing nozzle and other '~ , ' parts thereby obviating clogging. ' '`~' ' Yet another object of the invention is to provide a ` '~
.: .
gun for mixing and spraying polyurethane foam and like fluids '~
which can be easily purged when the gun is being used for inter- "'`, 10~ mittent spraying, and which is provided with à nozzle m~ember which can be~easily removed and quickly replaced after the ,~
completion of ma~or-length spraying operations. '' A further object is to provide a gun of the described ;'-, , ~ ., ~ kind which i8~ inexpensive' in initial cost, and~which can be ;,;' :: : ~ . ...
easily and effectively operated by even inexperienced personnel. ';
; And a~further obJect of the invention is to provide a '~
mixing and~dispenoing gun for polyurethane and like products '~, whérein interaction of the respective components is positively "
re,stricted~to~a~disposable or reconditionable nozzle.
~20,~ 0ther~ob~ects~and,advantages of the invention will,be- ~ '~ come appar~ént~upon reàding the following detailed description 'and;~upon~'referencé to the drawings. Throughout the drawings, like~rei'erence numerals refer to like parts.
Bri d Description of the Drawings , ,~, Fig. 1 is a general view showing use of the novel~', dispensing gun in a typical application;
' Fig. 2 is a side elevational view showing in further ,~, detail the nove,l dispensing gun; `~
_ 5 _ - , --~ ~
~` 16)44~64 Fig. 3 is a sectional view taken substantially in the plane of line 3-3 in Fig. 2 showing in further detail parts of the dispensing gun as they appear when the gun is discharging a multi-component product fluid; , Fig. 4 is a fragmentary sectional view similar to ,~ ' Fig. 3 and showing the gun parts as they appear when a purge fluid is being directed through the gun; ,,~
Fig. S is an exploded view showing in further detail `~ ~
; portions of the purge fluid regulating mechanism; ~, , Fig. 6 is a front elevational view of the gun; ,,~, , ,,~
Fig. 7 is a central sectional view similar to Fig. 3 ~,,,;~ , ~, but showing a modified form of the invention wherein interaction ~
of the fluid components is restricted positively to the nozzle; ~'`~''''~' ,, ,Fig. 8 is an enlarged séctional view taken along the ' line 8 - 8 of Fig. 7 to show the check valve retainer; and '.
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Fig. 9 is a view similar to the showing of Fig. 7 ' ~
but~suggesting one of the check valves in open condition as , might~occur on plugging of the opposite line. ~
: ..~
~ Deocril~b~ b~ !tion '
2 0~ . ~ Whlle~ the invention will be described in'connec- ~
tion with;~a preferred embodiment, it will be understood ,, that~it is not intended to limit the invention to that , embodiment.~ On the,contrary, it is intended to cover all ,~ -~
alternatives, modifications and equivalents as may be in-~ cluded within the spirit and scope of t,he invention. ' :: ~ ' ~. :: .
.,.,...
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`` lQ4~ ;4 Turning first to FIG. 1, there is shown a typical embodiment of the present invention in use. A worker 10 is shown spraying a wall surface 11 with a urethane foam product 12 by means of a spray gun 14 embodying the present invention. ;~
The fluid components of the urethane foam are stored separately in individual pressurized vessels 16 and 17 which, in turn, may be located for convenience within a carrier 18. The ure- ;
thane foam components are separately lead to the spray gun -14 by individual connector hoses 19 and 20 where the components are mixed and are then discharged or sprayed against the wall 11 as urethane foam 12. `
In accordance with the invention, a relatively inert fluid is discharged through portions of the gun to purge mixed product foam fluid from it after gun use is terminated. This `~
purge fluid can also be conveniently stored in a pressurized . .
vessel 21 which may be mounted or retained within the carrier 18, and is separately lead to the gun l4 by a connector hose ;
22. :`
As shown in FIGS. 2 and 6, this mixing and discharge spray gun 14 includes a housing 25 from which depends a handle 26 which is formed to encourage easy gun use and deft handling.
e product fluid constituent lead-in hoses 19 and 20 are securely attached to the gun housing 25 by interconnector fittings 27 and 28, respectively. In the illustrated embodi-ment, these fittings 27 and 28 are each formed with grooves 29 and 30 of reduced diameter. The grooves 29 and 30 are engaged by housing lock screws 31 and 32, respectively, which serve to secure the fittings 27 and 28 and their hoses 19 and ' '', .

.. ~ .. . . ... . .... .. .

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~- 16)4~64 20 against axial motion or inadvertent disconnection from the gun 14. Seals such as 0-rings 34 or other known devices can be provided to prohibit fluid leakage.
For controlling the flow of each product fluid `
component through the gun, a plurality of primary valves 37 and 38 intercept and selectively inhibit or permit fluid flow. -In the illustrated embodiment, these valves include respective ball members 39 and 40 adapted for fluid-tight engagement with seats 41 and 42 respectively formed in the housing 25.
10 Normally, these balls 39 and 40 are biased into their closed, ;~- ~
fluid-flow inhibiting positions; here, this biasing action is -accomplished by valve coil springs 43 and 44 interposed between the fittings 27 and 28 and the valve ball members 39 and 40. S ' ~', Simultaneous actuation of these valves 37 and 38 ~-, ., ~ - .
and consequent product fluid component flow is caused by a trigger mechanism 50 as shown in FIGS. 2 and 3. A trigger ~
member 51, conveniently pivoted to the housing 25, is adapted ~-to engage thrust pins 53 and 54 which are mounted for sliding ~-.. "~ .. . ~
~ motion in the housing 25. Rear ends 56 and 57 of these pins ~ . -. . .
~;2053 and 54 are located to engage the valve ball members 39 and 40;and move them from their closed seated positions shown in ?`'i '~
.,, ~ . .
FIG. 4 to open unseated positions shown in FIG. 3. When pres~
sure on the trigger 51 i5 released, biasing devices such as compression coil springs 58 and 59 draw the pins 53 and 54 `
away from the valve ball members 39 and 40 and permit the balls `;- ~-to relocate against the seats 41 and 42. Guide collars 60 and `~
61 can be provided to insure smooth spring~ trigger and valve action. ^

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4 i ~
, . ..
As shown particularly in FIG. 2, a trigger keeper 62 can be included if desired to retain the trigger and asso-ciated valves in either a closed position interdicting fluid flow as illustrated or, alternatively, in an open position permitting fluid flow. This is accomplished by providing recesses 63 and 64 in the gun handle 26. A leg portion 65 ~.
of the keeper 62 is adapted to be disposed within either :
of these recesses 63 and 64 and to retain the attached trigger .~.
. . , 51 in the corresponding location.
10 . Downstream from the valves 37 and 38 are primary passages 67 and 68. These passages, here formed in the housing 25, establish separate fluid pathways between each primary valve 37 and 38 and a mixing and discharge nozzle member 70 : (FIG. 3~. To encourage thorough mixing of the separately received product fluid constituents, a helically shaped baffle member 71 is provided within the nozzle 70. Component mixing and positive product fluid discharge is further encouraged by ~.
a nozzle orifice 72 which is sized to permit a free or ready flow of product flu~d through the nozzle with sufficient velo- . :
.~20 city to create a relatively well-defined, easily.directed stream. ~
.
- .Tt is a feature of the invention that this nozzle member 70 cah be quickly.removed from the gun and a fresh :~ .replacement nozzle easily installed when desired. To this .
end, the illustrated nozzle 70 is provided with a somewhat .:
.
enlarged bayonet base 74 adapted to mate with a bayonet recess :
75 formed in the housing 25. Nozzle extensions 76 and 77 are .-~
adapted to be matingly inserted into receiving parts 78 and 79 ;
' .. . .~

. . . . ~ . . . . ~ ~ .

... .

1~)44tj~4 and to form fluid-tight connections therewith. Thus, product fluid constituents flowing rom the valves 37 and 38 flow ;
down the primary passages 67 and 68, through the extensions ;
76 and 77, and comingle within the interior of the nozæle member 70 Positive constituent mixing action.is encouraged by the helical baffle member 71, and the mixed, foaming fluid is `...... ... - .
discharged through the nozzle orifice 72 toward the target area. -:
To securely retain the nozzle member 70 and to assist .`
in its replacement in the gun when desired, a nozzle ejector~
retainer léver mechanism 80 is provided as illustrated in FIG. 2. The lever mechanism 80 is provided with a first exten-sion 81 terminating in a hook 82 which is adapted to engage an annular collar 84 partially defining the enlarged bayonet base 74 of the nozzle 70. Interaction of.the hook 82 and collar 84 prevent.accidental ejection of the nozzle from the gun when nozzle removal is not desired. A second lever exten~
sion 85 is adapted to engage the rear of the nozzle member 70 -~
as illustrated in FIGS. 2 and 3. Pivotal motion of the ejector~
retainer lever 80 from the position shown in solid lines in 20 FIG. 2 to that shown in dotted lines causes the second lever ;
extension 85 to move forward and forcibly eject the nozzle 70 ~.~
*om the gun housing 25. The lever 80 is normally retained .~ . .
in its nozzle-retaining position by a biasing means such as a coil spring 87 conveniently mounted atop the gun housing 25. .
In accordance with the invention, the primary passages 67 and 68 and at least portions of the nozzle 70 can be purged ~-of constituent and mixed product fluid. To this end, a secondary r 1¢~4~4 valve 90 is provided for controlling the flow of a purge fluid lnto the gun, and secondsry passages 91.and 92 establish purge ..
fluid pathways between the secondary valve 90 and respective primary passages 67 and 68. By this arrangement, the purge fluid is caused to ~low through at least portions o~ each primary passage 67 and 68 and the nozzle 70 in purging the gun, and extensive, positive purging is encouraged. The purge fluid is preferably compressed air, nitrogen or some other inert fluid which will not.react with the product fluid,. the product fluid constituents, or gun parts.
It is a feature of the invention that the secondary .
.
passages 91 and 92 intersect the primary passages 67 and 68 at respective points 93 and 94 adjacent the primary valves 37 and 38. Purge fluid is thus routed past the primary valves ..

37 and 38 to discourage valve clogging and consequent gun mal-! . : .
function. Formation of both the primary passages 67 and 68 .
and the secondary passages 91 and 92 can be conveniently accom- `-plished by driLling them through work recesses 95. After passage I .
formation is completed, these recesses 95 can be closed off by cap screws 96.
- It is a feature of the invention that the secondary --or purge fluid valve 90 can be controlled independently of the gun trigger even though the operator may still hold the gun handle 26 and trigger mechanism 21 in one hand. To this end, the illustrated valve 90 includes a hollow quill member 97 which is adapted for connection to the purge fluid hose 22. .
j ,.
As illustrated in FIGS. 3, 4 and elsewhere, thls hose-quill 1.
,:

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- ` 1()44~4 interconnection i9 accomplished by providing a hose fitting -, 98 with a groove 99 of restricted diameter. On an enlarged ;,,- ~ , portion 100 of the quill 97, a lock screw 101 is provided to ~, intercept and engage the groove 99. One or more O-rings 102 ,~' provide fluid-tight interconnection between the quill 97 and ,~ '-the fitting 98. The enlarged quill portion 100 is here knurled to make quill rotation and secondary valve operation easy.
The quill 97 and a quill-receiving housing well 107 ~, .....
are provided with mating threads 108 and 109. When the quill '~'' 10 97 is turned about,its axis relative to the housing 25, inser- 'i tion of the quill into the housing 25 or alternative partial ' ,.. ~.
withdrawal of the quill from the housing occurs. ,,,, " ,, The quill member 97 is also provided with a bore 111, . . . .
as best seen in FIG. 4, down,which the purge fluid can pass. ,',~ ~

Adjacent an end face 112 of the quill, a plurality of radially ,' ''' - ' , oriented passages 113 permit flow of the purge fluid out of ''' the quill member,97 and into an annular chamber 114 between a il;", ',,~, ~.il, .
~ reduced-diameter quill tip 115 and the housing well 107. An ';,'~ ,-'f "
O-ring 117 is provided to prohibit purge fluid from flowing 20 ~backwards out of the housing past the quill member. ~ ', .,;
~, ' In a bottom 118 of the housing well 107, one or more ,,;
orifices 120 and 121 permit purge fluid to flow from the chamber , ,~
114 to the secondary passages 91 and 92 as shown by the arrows ,' A in FIG. 4. However, when the quill member 97 is fully ' inserted into the housing well, purge fluid is prohibited `;
from flowing through the orifices 120 and throughout the gun ,, by sealing abutment of the quill face 112 against the well ' .

- 12 - ~ , 16)44~4 i bottom 118, as shown in FIG. 3. By opening the quill 97 an appropriate amount, purge fluid can flow freely through the gun and drive out the purged material without creating more than a relatively low back pressure in the,nozzle 70 behind ~, the-dispensing orifice 72.
It is a feature of the invention that wear and tear ~
on the well bottom 118 is inhibited and purge fluid flow -,;
encouraged by a washer'member 130 adapted to be retained in ,' the well bottom 118. Here, this washer member 130 is provided ,'-~
10, wLth orifices 131 and 132 adapted to align with the housing secondary passage orifices 120 and 121 to permit purge fluid to pass from the quill and well into the secondary passages 91 `~
~; and 92. The washer 130 is retained in the housing well 118 ' ~, Ln Lts orifice-aligned position by one or more alignment pins 135 which extend between pLn-receiving recesses 136 in the ,~
housing 25 and pin-receiving recesses 137 in the washer 130 '~
itself. To extend the service life of the gun 14, this washer 'i' 130 is farmed of a polytetrafluoroethylene material whLch is ' Lnert~with respect to the purge fluid and each product fluid 20'~ component.
' The described construction of the spray gun makes its '~'~
use easy by,even inexperienced personnel. Each product fluid constLtuent is lead to the gun along- separate product fluid constituent flow paths by the individual hoses 19 and 20. Flow `''' , of each product fluid constituent is controlled by a valve means 37 or 38. Each fluid constituent passing the valve 37 or 38 ?
flows down a separate primary,passage 67 or 68 to the common - 13 _ - ~ '~` - -' . ,,, `'~,` ' "' ~~~` 10 4~ ~6 4 mixing and dispensing nozzle chamber 70. This nozzle and ,' the gun itself are adapted to accurately direct the mixed foaming product to a target area. After gun use-and when the gun will not be in use for a short time, a secondary valve 90 is opened by turning the knurled portion 100 of the quill ',' , 97. Purge fluid flows down secondary passages 91 and 92, ,'ri' ,1 ' .
past the primary valves 37 and 38, and into the primary ,-passages 67 and 68 to drive out the product fluid constituents ' , ' from the primary passages and from the nozzle itself, thereby ~ ,. , 10 purging the gun even when a relatively fast-setting product ,~
foam~is formed by the fluid constituents. If the gun will ,`~,'' no't;be used for relatively long periods of time, the nozzle .,~
70 can be~reved from the gun, thereby eliminating the i~
possibility that any unpurged f,oam product could flow back-wards into upstream portions~ of the gun. When gun use is a~ga,in~desired, a fresh nozzle can be installed. '' While a~particular emb,odiment of the invention has ~7 beèn~thus~far shown and describedS it should be understood, ' ~ ' ,of course, that the invention is not limited thereto since '-~ -,20~ many~ ~ dific-ations may be made, Therefore and in order to , enbnnce the~4nderstanding~of`the invention, one such mo,dified ,OY`
form of the invention is~shown in Figs. 7-9 inclusive. Because the~embodiment of~Figs. 7-9 incorporates many of the elements '~ ,' employed~in,the embodiment`of Figs. 1-6, like numerals have been~used to designate like parts with the suffix letter "A"
béing employed to distinguish those common elements assqciated with the embodiment of Figs. 7-9.
. ... .

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The embod~ment of Figs 7-9 is characterized by the provision of check valves within the nozzle 70A for use in selectively admitting fluid product constituents into à
mixing chamber-portion 138 of the nozzle 70A and, more importantly, for obstructing retrograde flow. Provision of check valves of the type to be described hereinafter positively restricts physical and chemical interaction of the product constituents to a separate nozzle member which may be dis-cardet or reconditioned. The check valves thus prevent one product constituent from leaking across the nozzle and into the companion product constituent passage and plugging up the gun 14A, as might otherwise be experienced upon loss ~`-of pressure in one constituent line only or a change in the evenness of the trigger pull, for example. Thus, while it , .
ls not possible to inspect the gun system visually, the described check valve arrangement confines problems arising from~parts failure and resulting in constituent intéraction, to the~nozzle which can be removed for trouble-shooting ~:~ purpo-es.
I~- 20 ~ The check valve arrangement to be described also allows~different pressures to be used on the various product coDstituent lines while maintaining a preselected stoichio~
mètric~ratio of the constituents themselves. Viscosity variables in the product constituents may also be accommodated ~ -by proper design of the check valves of the invention. .
Referring particularly to Fig. 7 and with secondary ~;

- 15 - t;

1~4~664 reference to Figs. 8 and 9, the nozzle 70A is constructed to ;~
include a helicalIy configurated static mixing member 71A , -disposed in the mixing chamber 138 spaced flowpathwise downstream from a pair of tubulations 140. The tubulations 140 are intended to fittingly engage the bores 78A and 79A
and are, for this purpose, provided with a plurality of annular ;~
sealing ribs 142, best seen in Fig. 9. Each of the tubulations 140 is fashioned with a conically tapered tip 144 for facility ~;
in inserting the tubulation into the appropriate bore in the gun housing. The tip 144 of each tubulation 140 is centrally apertured with a cylindrical hole 146 which establishes an -~
inlet for the product fluid constituent, the hole 146 opening r : .
into an internal bore 148. The bore 148 is conically tapered ~;
to flare outwardly in the direction of mixing chamber 138 to establish a valve seat in a check valve arrangement 150.
It is to be appreciated that an important feature of the present invention resides in the provision of check valve arrangements lS0 as an integral part of the nozzle 70A;
and in addition to the valve seat defined by the conically ~20 tapering bore 148, each check valve arrangement 150 includes a valve ball 152 which is disposed between the valve seat `~
..
and a coiled biasing spring 154. The strength of the spring 154 is selected to urge the valve ball LS2 into a position in -, the conical valve seat of bore 148 normally closing off communication through the corresponding tubulation 140, the `
strength of spring 154 being additionally selected to respond ..

, ~ .

.

, . . . . . , , . . . . . ~ . . . - .
, , - , , , ~ , , ,, : : .-~ '~4~;64 to fluid pressure in the tubulation so as to locate the valve ball in a position selectively opening the tubulation to -~
- product constituent flow.
In order to establish a preselected positional relationship between the valve ball 152 and the biasing spring 154 relative to the valve seat defined by bore 148, the nozzle 70A includes a retainer 156, best seen in Figs. 8 and 9. A solid cylindrical, centrally disposed, upstream facing stem 158 extends from the body of retainer 156 to -enter a matching bore 160 in the nozzle base for fixing the ; retainer i~ position; and if desired, a film of adhesive may -be disposed between the stem and the bore 160 to preserve tbe assembled relationship. Outboard of the stem 158, a pa~r of parallel, tubular stem members 162 extend toward the - -tubulations 140 in axial alignment therewith. The members 162 communicate through cylindrical apertures 164 formed therein,~the apertures 164 passing the respective product constituents through the retainer and into the mixing chamber iif 13&. The;members-162 are also provided with radial bores 166 ` 20 to provide supplementary means for egress of the fluid product constltuents. Locating ears 168 may additionally be included ~:
on the reta~iner 156 for supplemental aid in mounting and positioning the same.
It is to be appreciated that the check valves 150 operate independently of each other and in response to the respective biasing spring and product constitue~nt pressures, ~r ~

' ", ~ , ... , , ~

~ 6 4 As is suggested in Fig. 9, one valve ball 152 may be inad-vertently seated so as to close off the corresponding tubula-tion 140 while the companion valve ball is urged by product ~
fluid pressure from its seated condition indicated in broken -outline at 170 to a position, shown in solid outline, opening . , .:
~ its corresponding tubulation and admitting the corresponding ,.; .
~ fluid product constituent into the mixing chamber 138. Such :. ~
a condition is prevented from leaking constituent from bore 78A to bore 79A by the closed check valve. Any product conseieuent interaction is thus restricted to the nozzle 70A.
The nozzle base advantageously includes an axial locating rib 172 which fits into a groove 174 in the gun housing for aligning the tubulations 140 with the bores 78A -~
and 79A.
~:~ : ;"' The drawings and the foregoing descriptions are not intended~to repre`sent the only forms of the invention in -regard~to~thé details of its construction and manner of operation. ~Changes in form and in the proportion of parts, - :, i.,~. .
as~well as the substitution of equivalents, are contemplated -~
20~ as~c~ircumstances 9 suggest or render expedient; and alt~ough specific ~terms have been employed, they are intended in a generic and descriptive sense only and not for the purposes of limitation.

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Claims (8)

The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. A system for mixing and dispensing a product fluid comprising: containers for separately stored constitu-ents; a gun housing connected to said containers; product constituent passages and primary valves in said gun housing, said primary valves being operable to control constituent flow through said passages; actuator means in the gun housing for selectively operating said primary valves to control the flow of corresponding fluid product constituents into the gun housing; replaceable nozzle means mounted in said gun housing for receiving and mixing the product constituents and for dispensing the resultant product, including a mixing chamber having a dispensing orifice, a pair of product con-stituent tubulations opening individually into said chamber away from said orifice and having coupling means connected to a corresponding product constituent passage in said gun housing, and a check valve means mounted in said nozzle means flowpathwise between each of said tubulations and said mixing chamber for selectively admitting the corresponding fluid product constituent into said chamber and for obstructing retrograde flow.
2. A system according to Claim 1 wherein each of said check valve means comprises a valve seat, a valve ball confronting said seat and biasing means for urging said ball toward said seat and into a position normally closing the corresponding tubulation, said biasing means being responsive to fluid pressure in the tubulation for locating said ball in a position selectively opening the tubulation to product constituent flow.
3. A system according to Claim 2 which further includes retainer means fixed in said nozzle means for pre-serving a preselected positional relationship between said valve ball and biasing means and said valve seat.
4. A system according to Claim 1 which further comprises primary valves carried by the housing and connected to the actuator means for controlling the flow of each pro-duct fluid constituent through the gun; secondary valve means for controlling the flow of a purge fluid into the gun housing; and secondary passage means in said housing for establishing fluid pathways between the secondary valve means and each primary passage at a point adjacent the corresponding primary valve, the purge fluid being thereby caused to flow through at least a portion of each primary passage and the nozzle means in purging the gun.
5. A system according to Claim 4 which further comprises a secondary valve actuator operable independently of said trigger means for independently opening and closing the secondary valve means and correspondingly permitting and interdicting the flow of purge fluid through the gun housing.
6. A system according to Claim 4 wherein said secondary valve means includes a quill member adapted for connection to a purge fluid source, a passage in the quill permitting purge fluid flow through the quill, a housing well for receiving the quill and having at least one orifice inter-connecting the well to said secondary passage means and a quill face adapted to abut the housing well orifice and halt purge fluid flow when the quill is relatively inserted in the housing well, the quill face being spaced apart from the housing well and permitting purge fluid flow when the quill is relatively partially withdrawn from the housing well.
7. A system according to Claim 6 wherein said quill and said housing well are formed with mating threads, rotation of the quill relative to the housing in one direc-tion thereby causing quill insertion in the housing and interdiction of purge fluid flow, opposite direction quill rotation causing quill partial withdrawal from the housing and permitting purge fluid flow.
8. A system according to Claim 1 which further com-prises trigger means connected to the actuator means for open-ing and closing each primary valve to correspondingly permit and interdict the flow of product fluid constituents to the gun housing.
CA249,532A 1975-06-27 1976-04-05 Purgeable dispensing gun for polyurethane foam and the like Expired CA1044664A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US05/591,174 US4117551A (en) 1974-05-30 1975-06-27 Purgeable dispensing gun for polyurethane foam and the like

Publications (1)

Publication Number Publication Date
CA1044664A true CA1044664A (en) 1978-12-19

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
CA249,532A Expired CA1044664A (en) 1975-06-27 1976-04-05 Purgeable dispensing gun for polyurethane foam and the like

Country Status (2)

Country Link
JP (1) JPS598222B2 (en)
CA (1) CA1044664A (en)

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GB2542110B (en) * 2015-07-01 2018-04-11 Scotframe Timber Engineering Ltd Improved timber frame insulating elements

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Publication number Priority date Publication date Assignee Title
JPH06100503B2 (en) * 1984-03-27 1994-12-12 大塚電子株式会社 Probes such as colorimeters
JPH0222030Y2 (en) * 1985-08-14 1990-06-13
KR100301169B1 (en) * 1999-02-24 2001-09-22 성영동 Foaming gun for rolyurethane solution
TWI480104B (en) * 2008-04-24 2015-04-11 Graco Minnesota Inc Method of cleaning fast setting material spray equipment
TW201031845A (en) * 2008-05-16 2010-09-01 Graco Minnesota Inc Hose manifold with integrated filtration and shut-off check valves

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2542110B (en) * 2015-07-01 2018-04-11 Scotframe Timber Engineering Ltd Improved timber frame insulating elements

Also Published As

Publication number Publication date
JPS525868A (en) 1977-01-17
JPS598222B2 (en) 1984-02-23

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