Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
32
SI-6938
AERATOR PROPORTIONER FOR A GRAVITY FEED
FROZEN COMESTIBLE FREEZER
Cross References to Related Application,_If Any:
BACKGROUND OF THE INVENTION
Field of the Invention
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This invention relates to frozen comestible
freezer/dispensers, and particularly to a modified
liquid/air proportioner or carburetor containing check
valve means for preventing backflow of dis-charged
materials and air due to an imbalance of pressure which
may occur when withdrawing frozen comestible from the
freezer chamber.
Description of Related Art
U.S. Patent No. 4,221,117, assigned to the same
assignee as the present application, disclosed a prior art
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~31:3Z
device for proportioning a liquid comestible with air
enroute from a liquid comestible tank to a freezing
chamber in which the liquid comestible and air are blended
and cooled to a serving consistency. The patent disclosed
an improvement over earlier devices having a similar
function. The patented improvement eliminated adding air
to the liquid comestible via a single tube which often
created air bubbles in the liquid comestible in the
combined air and liquid fill tube. The patented
improvement accomplished this by utilizing a pair of tubes
wherein the aerator proportioner, or carburetor, had a
feed tube solely for liquid comestible and an air tube
solely for air.
Although the U.S. Patent No. 4,221,117 disclosure
provided a distinct improvement over the single tube
devices, when placed in an actual working environment,
there have been instances noted where when withdrawing the
product there is created a low pressure in the
freezer/dispenser unit tending to draw the product and air
into the unit in undesired proportions due to the unequal
pressures.
SUMMARY OF THE INVENTION
The proportioner or carburetor of the present
invention provides an improvement over prior art devices
the form of a "check valve" means for either or both the
air supply and the liquid comestible supply t.o the
proportioner or exit therefrom to the receiving chamber.
The check valve means provides for retention of the
desired proportion of air and feed, which at times in the
past has been lost because of a pressure imbalance
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existing in the hopper or receiving tank when compared to
back pressure in the freezing chamber or barrel.
The check valve means may take various forms, and the
preferred mode at present utilizes a "check valve" means
wherein each through-bore of the bushing member includes a
"cage" portion providing an inverted seat having a
configuration arranged to receive a floating closure
member, such as a ball or other object conforming to the
seat if and when pushed upwardly by fluid entering the
bottom of the bushing member due to undesirable pressure
imbalance. Closure thereby prevents the fluid from rising
in the respective tube.
Another uses flaps made of resilient, elastomeric
material supported by a bushing member secured to the
lower end of individual air and liquid comestible supply
tubes, the bushing member has a pair of through-bores
communicating with each of the respective tubes and
normally closed at the opposite ends of the respective
through-bores by the resilient flaps .
Other embodiments of the "check valve" means are also
disclosed herein. The term "check valve" is intended to
be considered in its broadest sense to define various
closures which automatically prevent backflow of air
and/or liquid comestible due to a differential in pressure
which may cause the mix to rise into the carburetor or
aerator proportioner. For instance, it is conceivable, as
herein disclosed, to provide a "trap", not unlike a "bell
jar", where the air tube comprises two separate sections,
the upper opening of the lower section of the member
extending to the mix level in the enclosed receiving tank.
The upper opening of the upper air tube section extends
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outwardly from the enclosed receiving tank, with its lower
opening extending into the mix and below the upper opening
of the lower section. Thus, if the mix should rise in the
chamber, air will be entrapped thereabove, not unlike a
"bell jar", and after being compressed to a predetermined
volume, the pressure of the compressed air will preven-t
the mix from rising above a pr~edetermined level.
Obviously, the second mentioned tube will have its end
raised above that predetermined level above which the mix
will not pass. Other embodiments will be hereinafter
discussed, each of which incorporate the inventive concept
disclosed herein.
The proportioner, or carburetor, may also be
configured to provide a chamber having two entrance
openings, one in connection with liquid comestible and the
other with air by means of a tubular extension rising
above the liquid comestible level, and with a single exit
communicating with a freezer mixing barrel. The chamber
contains a check ball valve for closure of either or both
entrance openings should there be a pressure imbalance.
DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a fragmentary vertical longitudinal
section taken through a frozen comestible freezer
embodying the present invention;
FIGURE ~ is a fragmentary enlarged view of a bushing
member containing air and delivery tubes and/or portions
containing through-bores, shown in FIGURE 1, and utilizing
entrapped or caged closure members to provide check valve
means for the respective through-bores;
FIGURE 3 is a fragmentary enlarged view of a bushing
member inserted at the lower end of air and liquid
comestible delivery tubes and utilizing resilient flaplike
members normally closing the lower ends of the respective
tubes;
FIGURE 4 is a fragmentary enlarged view of another
embodiment of this invention similar to the embodiment of
FIGURES 1 and 2, but illustrating retained ball closures
disposed in a separate bushing member located at the lower
end of a pair of air and liquicl delivery tubes;
FIGURE 5 is a fragmentary cross-section taken
approximately across lines 5--5 of FIGURE 1, but
illustrating another embodiment of the present invention;
FIGURE 6 is a cross-sectional view taken along lines
6--6 of FIGURE 5;
FIGURE 7 is a fragmentary sectional view of a modified
plug member illustrating the present invention in still
another embodiment;
FIGURE 8 is a fragmentary view of an inlet air tube
. 25 modified to disclose still another embodiment of the
present invention;
FIGURE 9 is a fragmentary view of still another
modified air inlet tube providing another embodiment of
the present invention.
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DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides an improvement to
frozen comestible freezers, such as that described in
United States Patent No. 4,221,117. As was disclosed
therein, and with reference to FIGURE 1 herein, a frozen
confection freezer 10 comprises a horizontally elongated
cylinder 11 enclosing a cylindrical freezing chamber 15
having its inner wall 8 cooled by refrigeration ducts 21.
Freezing chamber 15 contains an auger type blender,
agitator and aerator 12 mounted for rotation substantially
on the axis of the cylinder 11. Liquid comestible 9 in
tank 13 is fed through a through-bore 43 of a molded plug
member 35. Air enters tube 42 and both comestible 9 and
air are fed through the pipe or passageway 14 in-to the
receiving chamber 19, which is adjacent freezing chamber
15 and partially partitioned therefrom by the disk 20.
The aerator and agitator 12 may be made in any desired
form. It draws liquid confection 9 and air from receiving
chamber 19 through the peripheral gap between disk 20 and
the wall 8 of cylinder 11 and agitates7 mixes and blends
the air and liquid to aerate the liquid and cool the
aerated mixture to the desired serving consistency. The
proportion of air and liquid in the final mix will depend
upon the proportion of air and liquid in receiving chamber
19, and this depends upon the proper functioning of the
proportioner hereinafter described.
The illustrated aerator and agitator 12 has a drive
shaft 16 mounted at one end on an external bearing 17.
The opening 40 in the end wall 80 of freezer 11 through
which drive shaft 16 extends is sealed by a rubber cup
seal 18. Drive shaft 16 carries the disk 20 to which ends
of auger blade 23, scraper blade 27 and stay rod 30 are
attached. At the end of the blender 12 remote from the
disk 20 there is a bearing hub 24 which is supported on a
bearing boss 25 from the end wall or door 26 which closes
the end of freezing chamber 15. Hub 24 carries a bracket
29 to support the respective ends of scraper blade 27 and
auger blade 23 which are remote from disk 20. Hub 24 also
supports the end of stay rod 30 a'c its end remote from
disk 20. When drive shaft 16 is turned by a motor (not
shown), the stay rod 30, scraper blade 27 and auger blade
23 rotate as a unit. Blender bar 22 is held stationary by
its anchor rod 39 which is seated in a corresponding
groove in the side of end wall 26.
The end wall 26 of freezing chamber 15 has a dispenser
nozzle 31 with a handle 33 by which frozen confection of
serving consistency is dispensed from the freezing chamber
15 through duct 32.
The aerator proportioner 34 in passage 14 includes a
mounting plug 35. It desirably has an intermediate
portion 36 which seats into the passage 14 and is sealed
thereto by O-ring 37. The upper level portion 38 of the
plug 35 is considerably elevated above the bottom wall of
tank 13 and is provided with a peripheral finger grip
portion 41 so that it can be readily grasped by an
operator for purposes of manual manipulation of the plug
for inserting it into the passage 14 and removing it
therefrom.
Plug 35 provides support means for air tube 42 and
contains a liquid comestible fill through-bore 43 in the
lower portion 39. Air tube 42 extends through the plug 35
and through the upper level portion 38 thereof, and
downwardly into the lower portion 39. The lower portion
39 of the plug 35 extends into the passage 14 into the
receiving chamber 19. The air tube 42 also extends
upwardly from the plug 35 above the level of the liquid
comestible 9 in tank 13, so as to have its upper end
exposed to the air of the atmosphere.
The level of the plug may be finger adjusted to change
the proportion or over-run of air to liquid in the final
mixture. When frozen confection is drawn from the
dispensing spout 31, and blender 12 is rotating, it draws
liquid 9 and air from the receiving chamber 19 into
freezing chamber 15. This lowers the level of liquid 9 in
receiving chamber 19 and uncovers the lower ends of air
tube 42 and through-bore 43. Liquid 9 will then flow by
gravity and suction from tank 13 through the bore 43 into
receiving chamber 19. Air will be drawn by suction down
air tube 42 into receiving chamber 19. The flow rates in
tube 42 and bore 43 will be uniform and precise because
each carries only air or liquid and no attempt i5 made to
mix the two in these tubes. When the liquid level rises
in chamber 19 to or above the lower ends of plug portion
39 both liquid flow and air flow into receiving chamber 19
is simultaneously stopped. Accordingly, the proportion of
air to liquid is automatically regulated by the rising and
falling level of liquid 9 and the initial adjustment of
the level of the lower ends of portion 39 in receiving
chamber 19.
The upper end of the fill through-bore 43 terminates
at the bottom of a cup-like valve cage receiver 44 of the
plug 35-
The improvement provided by the present invention is
in the form of check valve means, variations of which are
disclosed in FIGURES 2-9, inclusive. A preferred
embodiment, as illustrated in FIGURES 1 and 2 comprises
the plug member 35 including an intermediate portion 36,
and an upper portion 38 and a lower portion 39. As
aforestated, the intermediate portion 36 is provided with
an integral groove acting to receive an O-ring 37 for
sealing the plug 35 with respect to the passage member 14.
The lower portion 39 is preferably divided into two
sections 39a and 39b, the section 39a including the
through-bore 43 and the section 39b arranged to receive
the lower end of the tube 42. Portion 39 is preferably
constructed to provide a separation wall 40 at its lower
end to permit the portion 39 to receive a bushing member
46 which may be slipped over and secured to the lower end
of the section 39a and 39b and which is arranged to
receive an air check ball 50 in its cup-like interior.
The bushing 46 is perforated with a plurality of apertures
55 at the lower end thereof to permit entry of air from
the tube 42. It will be apparent that any backflow from
the chamber 19 will be blocked by means of the ball 50
engaging the lower opening of the tube 42.
The liquid 9 enters the plug 35 through the upper
opening formed by inwardly extending flange portion 54a of
a check valve insert cage 56 received in the cup 44 of the
plug 35. The insert cage 5~ is provided with a tapered
seat 57 for receiving a ball 58. The lower end of the
valve seat is slotted between fingers 59 to permit egress
of the liquid 9 into the through-bore 43. The insert 56
may be snapped into place in the cup 44 by finger
pressure. It thus becomes accessible for cleaning
operations. It will be apparent that any backflow of
liquid comestible 9 tending to enter either or both the
air tube 42 or the through bore 43 will be checked by one
or both balls 50 and 58 (see phantom positions)
respectively forced against the opening at the bottom of
tube 42 and the apertured seat formed by the inwardly
extending flange 54a of -the insert cage 56. The outwardly
extending flange 54b provides a shoulder for supporting
the cage 56 at the top exposed surface of the upper
portion 38 of the plug member 35.
In the embodiment of FIGURES 3, a bushing member 46a
molded of plastic material is secured to the bottom of
separate delivery tubes 42 and 43a. Tube 43a delivers
liquid comestible 9 similar to through-bore 43 of the
embodiment of FIGURES 1 and 2. The bushing 46a contains
two through-bores 47 and 48 communicating respectively
with the lower ends of the tubes 42 and 43, being secured
thereto by force fit and/or applied adhesive. Located at
the bottom surface of the bushing member 46a is a
resilient flap member 49 formed from an elastomeric
material and providing separate check valves in the form
of laterally extending flap portions 50 and 51. The
portions 50 and 51 normally act as closures for the
through-bore 47 and 48 of the bushing member 46. The flap
- 25 member may be secured to the bottom of the bushing member
46 by means of a rivet or other suitable attachement
means.
The phantom position of the flap portions 50 and 51
are shown in FIGURE 2 to indicate the open position of the
flap member check valve upon demand of either air through
the tube 42 or liquid comestible through the tube 14 as
required on demand by opening the dispenser nozzle 31
during servinq of a frozen confection. Either or both of
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the check valve flap portions 50b and/or 51b will prevent
backflow of material from the receiving chamber 19 should
there be an air pressure imbalance between the pressure of
the freezing chamber 15 and the atmospheric pressure
exerted on the liquid comestible 9 and the air entering
the tube 42.
A modification of the embodiment of FIGURES 1 and 2
may be observed by the "ball-type" check valves of FIGURE
4. The phantom lines show the balls 50a and 51a in
closure position against the respective lower ends of
delivery tubes 42a and 43a, respectively, upon the
occurance of a pressure imbalance.
Another embodiment of similar performance is described
with reference to the view of FIGURE 5. This embodiment
utilizes a single air tube 42a and a modified plug 35
molded in two parts 35a and 35b which are joined together
as shown in FIGURE 5. The top portion 35a is formed to
provide a shoulder 53 for receiving the lower end of the
air tube 42a. The shoulder 53 opens up into a recessed
entrance 53a for receiving comestible 9. Both the lower
end of the tube 42a and the inner portion of the entrance
recess 53a communicate with a chamber 58, which at its
lower end defines a ball seat 62 arranged for reception of
a floating ball member 60 during closure of the chamber
58. (Obviously, if required because of consistency,
texture or ingredients, the ball may be spring biased
towards closure by means of a helical spring located
directly below the ball (not shown)~. The bottom portion
35b of the plug 35 is provided with a sealing gasket,
which may be in the form of an O-ring 61. With reference
to FIGURE 6, the internal chamber 64 includes a plurality
(4 in this case) of inwardly projecting ridges 65 to
support the ball duriny flow of the comestible 9 and air
entering from tube 42a. The structure prevents accidental
closure of the exit opening 66 and its discharge tube 67
secured thereto.
It will be apparent that the embodiment of FIGURES 1,
2 and 3 may readily be retrofitted to existing systems,
such as the apparatus disclosed in the aforementioned
Patent No. 4,221,117, whereas the ball-type check valve of
FIGURES 4-6, inclusive, may be utilized on newer machines
as they are introduced to the marketplace.
With reference to FIGURE 7, it will be observed that a
"bell jar" version of a check valve for a proportioner or
carburetor may also be utilized. In this embodiment, the
plug 35 may also be in the form of a two-part member.
That is, the lower portion 70 is externally threaded to
receive a threaded inverted cup-like portion 71 and which
is sealed thereto by means of an O-ring 72 seated in
matching grooves formed in both members 70 and 71. The
upper portion provides a "bell jar" air lock and further
supports an air tube 73 extending above the level of the
liquid comestible 9 and externally of member 70. The tube
73 is secured to the member 71 by conventional means such
an an adhesive or heat seal. It will be apparent from
FIGURE 7 that the length of the tube is sufficient to
extend below the height of a tubular extension 75
intergrally molded with the lower portion 70 of the plug
35. The distance "X" between the ends of the tube 73 and
the tubular extension 75 is a function of the head
pressure, which, in turn, is dependent upon viscosity and
may be determined by experimentation. The tube 73 may be
fitted to the upper portion 71 by thread means (not shown)
or other means for permitting the tube 73 to be raised or
- 12 -
lowered to vary the distance "X". The lower portion of
the plug 35 is supplied within an inlet opening or
entrance 76 and the aforementioned tubular extension 75
will determine the height of the level of the liquid 9
which will be substantially equivalent to the height of
the trapped air within the "bell jar" chamber 77. The
lower portion 70 is further sealed by O-ring 74 against
tube 14 to prevent leakage of liquid 9. The lower portion
70 is further formed to provide air and mix chambers 78
and 79, respectively.
Other possibilities for restricting air flow to
prevent backflow due to pressure imbalance are within the
province of the present invention. For instance, as shown
in FIGURE 8, the air tube 82 may be of a soft, squeezable
material that collapses when the change in pressure
increases and pops open during a dispensing operation upon
opening of handle 33. This embodiment suggests utilizing a
stiff air inlet tube 84 as disclosed in ~IGURE 9. Here,
the tube is provided with a constriction 85 acting, at its
lower inner bore to provide a seat area for receiving a
ball or other check valve member having a configuration
conforming to the seat 86 from movement within the bore of
the tube 84. The ball 87 may be of the floating variety
25 or may be provided with a spring 88 and washer 90
bearing, at its opposite end, against a lower tubular
constriction 89.
Thus, the present invention provides for an improved
non-pressurized frozen comestible freezer having the
features of previous freezers but without backflow
pressure problems due to an imbalance of pressure in the
freezer chamber when compared to the pressure of the
liquid comestible contained in a supply tank plus the air
pressure entering a carburetor or aerator proportioner.
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