Note: Descriptions are shown in the official language in which they were submitted.
I 2 Roy
The present invention relates to improvements in a
cleaning apparatus and process. More particularly, -the present
invention relates -to a method and an apparatus for automatically
cleaning dir-t from the surfaces of dirty objects by a washing
apparatus using high pressure jet sprays to agitate the cleaning
fluid in an immersion bath.
Litter and its impact on our environment is receiving
increased national attention. In response to this problem, some
states have enacted legislation which has banned the use of throw-
I away plastic, glass, and metal beverage bottles. Recent studies
have shown that this legislation has reduced the amount of litter
on our highways and other public property. However, this leg-
station has also created other unforeseen problems in the storage
and return of returnable beverage buttes
It is common practice in the beverage industry to use
plastic receptacles for shipping glass, plastic and metal bevel-
age containers. These plastic receptacles are normally formed
with a plurality of stiffening flanges and ribs which form a
large number of crevices within which dirt can accumulate. In
some instances, the plastic receptacles are composite
-- 1 --
2~5i3~i
structures which include removable secondary enclosures. For
hygienic and aesthetic purposes, it is desirable to clean these
receptacles each time they are returned to the bottling plant.
The art of cleaning an object by dipping it in an
acidic or basic cleaning solution so that the chemical soul-
lion attacks the surface contaminants is well known. This
method is economical and requires only the most simple equip-
mint. However, it is also time consuming and does not always
clean the crevices and holes in the object being so processed.
Furthermore, the cleaning solution often attacks the surface
of the object itself and, after a substantial number of clean-
in cycles, may have a permanent detrimental effect on the
appearance of the surface.
Cleaning objects by placing them in a liquid bath
and transmitting ultrasonic waves through the fluid in the
bath to impinge upon the surface of the object is also well
known. An example of a cleaning apparatus using ultrasonic
waves is disclosed in the parent application to the present
case. The ultrasonic cleaning method is more effective at
removing dirt than merely immersing the object in a chemical
bath. Unfortunately, as the length of time that any one
object is immersed in the bath is decreased, the number of
transducers needed to properly clean the object is increased
to make ultrasonics effective, there must be at least one
transducer element per gallon of cleaning fluid. While batch
cleaning using ultrasonics is well known, it is sometimes
extremely expensive to use ultrasonic cleaning equipment to
adequately clean objects in a very high volume production line
situation. Furthermore, ultrasonic transducers only loosen
the dirt but do not remove the dirt unless there is sufficient
exposure time and a sufficient amount of ultrasonic energy. A
thorough rinse is therefore essential to remove the dirt from
it
the object. Finally, all ultrasonic cleaners have the dozed-
vantage of being incapable of removing large pieces of debris
from the crevices and cavities of the object being cleaned.
Such pieces of debris as straw, broken glass and bottle caps
are often found within the plastic receptacles used by the
beverage industry when they are returned to the bottling
plant.
One method that has been used to increase the effect
tiveness of ultrasonic cleaning devices is to provide a pro-
wash station where the object is scrubbed prior to being immersed in the ultrasonic immersion bath. In the prewash
station, the object may, for example, be exposed to the scrub-
bring action of a high pressure spray of cleaning fluid. One
disadvantage with the use of a prewash station is that the
cleaning fluid from the prewash station cannot be permitted
to flow into the immersion chamber. If the gleaning fluid
from the pro wash station is allowed to flow into the simmer-
soon chamber and to mix with the cleaning fluid therein, the
effectiveness of the ultrasonic transducers will be greatly
decreased.
In the parent application to the present applique-
lion, it was proposed that a cleaning apparatus be provided
with a liquid immersion bath combining a chemical and a
mechanical cleaning action. The chemical cleaning action was
provided by using a cleaning fluid which reduces the surface
tension of the dirty object and of the dirt itself. The
mechanical cleaning action was provided by either transducers
or a series of high pressure spray jets which agitated the
fluid in the bath. While this apparatus produced the desire
able result of decreasing the number of transducers needed lore predetermined amount of dirt removal, the apparatus still
required the used of more caustic chemicals in the cleaning
~-~25~
fluid than may be desirable. Furthermore, the specific Papa-
fetus disclosed did not suggest that the fluid from the pro-
wash station could be permitted to be mixed with the fluid in
the immersion bath.
The present invention provides a novel method for
cleaning dirty objects and further provides a novel apparatus
using the method. In the method of the present invention, the
dirty object is first prewashed with a high pressure spray
adapted to impinge directly on the surface of the dirty object
to remove a portion of the dirt from the surface of the
object. The object is then immersed in an immersion chamber
containing heated cleaning fluid for a predetermined period of
time. After the object has been immersed in the cleaning
fluid in the immersion chamber for the predetermined period of
time, the cleaning fluid is agitated by high pressure jets.
The high pressure jets are adapted to create substantial turn
Balinese in the cleaning fluid so that additional dirt is loo-
sexed and removed from the surface of the object and so that
large pieces of debris are lifted away from the object.
Finally, the object is removed from the immersion bath and is
rinsed with a high pressure spray of rinsing fluid adapted to
impinge directly on the surface of the object to remove the
cleaning fluid and remaining dirt from the object.
In the preferred embodiment, the method misapplied
to a continuous process for cleaning multiple dirty objects.
Thus, the dirty objects are first passed through a prewash
chamber where they are exposed to the scrubbing action of sex-
oral high pressure spray jets of cleaning fluid. The initial
scrubbing action removes or loosens a portion of the dirt.
Next, -the objects are passed through a longitudinally extend-
in immersion chamber having a soaking station and a scrubbing
station. In the soaking station, additional dirt is loosened
. , . j
~2~25~
by the cleaning fluid. In the scrubbing station of -the simmer-
soon chamber, additional dirt is loosened and removed from the
object by the vigorous mechanical scrubbing action of turbo-
fence created by a high pressure fluid distributor. Finally,
the remaining dirt is removed from the object by passing the
object through a rinse chamber. In the rinse chamber the sun
faces of the objects are exposed to a high pressure spray of a
rinsing fluid or wetting agent which removes the dirt from the
object and also assists in drying the object.
The apparatus of the present invention is character-
iced by a housing. prewash chamber is provided at the
input end of the housing. The prewash chamber has a first
spray tunnel mounted therein for spraying cleaning fluid
directly at the surfaces of the dirty ob;ectsO A rinse champ
bier is provided at the discharge end of the housing. The
rinse chamber has a second spray tunnel mounted therein for
spraying rinsing fluid directly at the surface of the objects.
An immersion chamber is provided in the housing between the
prewash chamber and the rinse chamber. A high pressure fluid
distributor is mounted in the portion of the immersion chamber
nearest the rinse chamber. A transporting apparatus for move
in the objects serially through the prewash chamber, the
immersion chamber and the rinse chamber are provided. Guide
bars are mounted in the housing for guiding the objects son-
ally through the wash chamber, the immersion chamber and the
rinse chamber.
The cleaning apparatus further is provided with a
filtering apparatus interconnected with the portion of the
immersion chamber nearest the prewash chamber to remove
therein at least a portion of the dirt dissolved in the clean-
in fluid. A first high pressure pump is provided for drawing
cleaning fluid from the filtering apparatus, pressurizing the
5 -
~2~53~'~
gleaning fluid to a predetermined pressure level and deliver-
in the pressurized cleaning fluid to the first spray tunnel.
A second high pressure pump is provided to draw cleaning fluid
from the filtering chamber, pressurize the cleaning fluid to a
predetermined pressure level and deliver the pressurized
cleaning fluid to the high pressure fluid distributor.
Thus, the present invention provides a cleaning
apparatus which will remove dirt from dirty objects and will
effectively clean a dirty object in one pass through the Papa-
fetus. To accomplish this, the surface tension of the dirt and of the object is
pa -
I
reduced by the action of the cleaning fluid in the soaking stay
lion of the immersion chamber. Another portion of -the dirt is
loosened and the loosened dirt is removed by the vigorous scrub-
bring action of the turbulent cleaning fluid in the scrubbing station
of the immersion chamber. The remaining portion of the dirt and
the cleaning fluid residue is removed from the object by the vogue
porous mechanical scrubbing action of the rinsing fluid from the
high pressure fluid distributor.
The present invention also provides an inexpensive
cleaning apparatus adapted for a high volume batch operation.
The present invention again provides a high pressure
fluid cleaning apparatus in which a transporting apparatus is pro-
voided to drive multiple dirty objects through the apparatus so as
to maintain the dirty objects in a longitudinally spaced relation-
ship.
The present invention further provides a method of
cleaning objects by a mechanical and chemical cleaning process
which minimizes the amount of caustic chemical required for sails-
factory cleaning of the dirty objects.
The present invention again provides an apparatus which
will mechanically and chemically remove dirt from dirty objects
in one pass. To achieve this object, a portion of the dirt is
loosened and removed by the vigorous mechanical scrubbing action
and by the chemical action of the cleaning fluid from high pros-
sure jets of the firs-t spray tunnel. Another portion of -the dirt
is loosened by immersion of the object into -the heated cleaning
fluid in the soaking station of the immersion chamber. Still
another portion of the dirt is loosened and removed by the vigor
rows scrubbing action of bye turbulent and agitated cleaning
fluid in the scrubbing station of the immersion chamber. The
remaining dirt and
-- 6 --
I
the cleaning fluid residue is removed from the object by -the
vigorous mechanical scrubbing action of rinsing fluid from the
high pressure spray jets of the second spry tunnel.
The invention also provides an apparatus which will
mechanically and chemically remove dirt from dirty objects and
will mechanically remove large pieces of debris from the objects.
This is accomplished by the vigorous action of the -turbulent and
agitated cleaning fluid in the soaking station of the immersion
chamber.
The invention further provides an apparatus which
mechanically and chemically removes dirt from dirty objects in
which a transporting apparatus is mounted in a prewash chamber,
immersion chamber and rinse chamber. The transporting apparatus
is adapted to drive dirty objects in a longitudinally spaced
relationship -through the apparatus. Thus, the entire outer sun-
face of the dirty object is exposed Jo the scrubbing action of
the high pressure spray jets in -the prewash chamber, the action
of the cleaning fluid in the soaking station, the scrubbing
action of the turbulent cleaning fluid in the scrubbing station,
and the scrubbing action of the high pressure spray jets in the
rinse chamber.
The present invention again provides a method for
cleaning objects by combining the mechanical and chemical cleaning
from a process utilizing high pressure spray jets with -the
mechanical cleaning from a process utilizing an immersion bath
which contains heated and agitated chemical fluid. In addition,
the method utilizes high pressure spray jets in a rinse chamber
in order to fully clean the object.
The present invention will be further illustrated by
way of the accompanying drawings in which:
7 --
~22~
Figure 1 is a perspective view of an example of the
cleaning apparatus of the present invention having a prewash
chamber, an immersion chamber, and a rinse chamber;
Figure 2 is an enlarged perspective view with parts
cut-away of the immersion chamber of the cleaning apparatus of
Figure 1 and illustrates internal components of the cleaning
apparatus and a dirty object capable of being cleaned by the
cleaning apparatus;
Figure 3 is a partially cutaway top view of the
cleaning apparatus of Figure l;
Figure 4 is a partially cut-away side view of the
cleaning apparatus of Figure l;
Figure 5 is a perspective side view of a spray tune
not and a portion of a feed conveyor which is provided within
the prewash chamber of the cleaning apparatus of Figure l;
Figure is a perspective side view of a spray tune
not which is provided within the rinse chamber of the cleaning
apparatus of Figure l;
Figures 7 through 11 are partial views of the clean-
in apparatus of Figure 4 taken, respectively, along -the lines
7-7 through 11-11 thereof;
Figure 12 is a perspective view similar to Figure 2
and illustrates a modified cleaning apparatus according to the
invention; and
Figure 13 is a sectional view similar to -that thus-
treated in Figure 10 and depicts the high pressure spray jets
to -the immersion chamber of the cleaning apparatus of Figure
12.
Referring now to the drawings, and more particularly
Figures 1 through 4 thereof, an example of an apparatus for
cleaning dirty objects is generally designated by -the role-
fence numeral 10. In the example illustrated, the dirty
?!~ - 8 -
2 I
object to be cleaved is a plastic receptacle 12 figure 2) for
soft drink bottles. The plastic receptacle 12 has a bottom
wall 14, four sidewalls aye through 16d, and two handles aye
and 18b. The receptacle 12 has an internal compartment 20 for
storing soft drink bottles. Those skilled in the art will
recognize that the cleaning apparatus 10 also has application
for cleaning other dirty objects such as plastic, wood, metals
or other containers used in dairy, meat, confectionery, bake
cry, and other food industries. The present invention also
Lo has application for cleaning plastic members, machine parts
and similar dirty objects.
As shown in Figure 1, the cleaning apparatus 10 is
enclosed within a housing 11 having a longitudinally extending
top wall 22, two longitudinally extending sidewalls aye and
24b and two end walls aye and 26b. One of the end walls, end
wall aye, is provided with an inlet passage aye for-admission
of receptacles 12 into the housing 11. The other of the end
walls, end wall 26b, is provided with an outlet passage 28b
through which receptacles 12 exit the housing if after they
have been cleaned. The housing 11 of the cleaning apparatus
10 is further provided with a bottom wall or floor 29,
described later. The walls of the housing 11 may be thermally
insulated to reduce the heat loss from the fluids within -the
chambers and to thereby minimize the energy cost associated
with maintaining the fluids at a desired temperature.
The interior of the housing of the cleaning appear-
tusk 10 is divided into a prewash chamber 30, an immersion
chamber 32 and a rinse chamber 34 serially arranged between
the inlet passage aye and the outlet passage 28b. The details
and the function of each of the chambers 30 through 34 within
the housing of the cleaning apparatus 1`0 will be described in
detail shortly.
~22S3~
As best shown in Figures 1 and 4, the floor I has a
horizontal central portion 36 in the central portion of the
immersion chamber 32. The floor 29 further has horizontal end
portions aye and 38b located in the prewash chamber and the
rinse chamber, respectively. The horizontal end portions aye
and 38b are each located in a plane above the central portion
36. Intermediate sloping floor portions aye and 40b are pro-
voided within the immersion chamber 32 between the end portions
aye and 38b, respectively, and the central portion 360 An
additional vertical wall 42 is provided between the immersion
chamber 32 and the rinse chamber 34. A passage 43 is provided
through the wall 42 for the receptacles 12.
The details of the prewash chamber 30 are best
illustrated in Figures 3 through 5. The prewash chamber 30
contains a first spray assembly or tunnel I. The first spray
assembly 44 includes a pair of tubular end frame members aye
and 46b which are arranged to form an open rectangle. Several
tubular cross members 48 are mounted longitudinally between
the tubular end frame members aye and 46b. The frisk spray
assembly 44 is fed by a high pressure pump (Figures 1 and 3)
50 which receives cleaning fluid withdrawn from a cleaning
fluid recirculating apparatus 66, described later herein. The
pump 50 delivers cleaning fluid at a pressure in the range of
seventy to eighty t70-80) prig to the first spray assembly 44.
The preferred delivery pressure is seventy-five (75) prig.
Several spray nozzles 52 are mounted to the tubular cross mom-
biers pa so as to direct several first spray jets of cleaning
fluid into the interior of the spray assembly 44 and directly
at the surface of the receptacle 12. The spray nozzles 52 are
selected so as to maintain a high pressure over a great!dis-
lance and have an aperture of approximately eighty thousands
of an inch (.080") in the preferred embodiment. The high
-- 10 --
I
pressure spray jets produced by the nozzles 52 form high
velocity streams which mechanically scrub the dirty object so
as to loosen or remove a portion of the dirt from the recap-
lade. The combination of the scrubbing action of the fluid
spray and the chemical action of the cleaning fluid losses or
removes a portion of the dir-t from the dirty receptacle. The
cleaning fluid within the prewash chamber 30 is permitted to
flow freely from the prewash chamber into the immersion champ
berm
I The details of the immersion chamber 32 are best
shown in Figures 2 through 4. The immersion chamber bath 32
is filled to a predetermined level with a chemical or cleaning
fluid preferably containing a non-foaming agent. The type and
concentration of the cleaning fluid depends on the nature of
the dirt to be removed and the degree of cleaning required.
Many appropriate cleaning fluids are well known in the art and
are commercially available. In the example illustrated in the
drawing, one percent to two percent detergent in the cleaning
fluid has been found to be acceptable.
The immersion chamber is functionally divided into a
soaking station 60 for presoaking the receptacles 12 and a
scrubbing station 62 for scrubbing the receptacles 12.
The soaking station 60 of the immersion chamber 32
is located near the prewash chamber 30. The soaking station
60 is provided to permit the cleaning fluid to act to reduce
the surface tension of the receptacles 12 and the dirt on the
receptacles. A drain passage 64 (shown in figure 1) in the
side wall 24b of -the housing permits a portion of the cleaning
fluid to be drawn from the soaking station 60 into the clean-
in fluid recirculating apparatus 66. The drain passage 64 is
preferably located in the first one third of the immersion
chamber 32 so as not to reduce the turbulence of the fluid in
` v -- 1 1 --
the latter one half to one third of the immersion chamber The
fluid recirculating apparatus I has a housing 68 defining a
fluid tank 70. A filtering apparatus (not shown) is provided
within the fluid tank 70 for removing dirt from the cleaning
fluid therein.
The scrubbing station 62 of the immersion chamber 32
is located near the rinse chamber 34. The scrubbing station
62 is provided with a high pressure fluid distributor I or
74' adapted to agitate the cleaning fluid in the latter port
lion of the immersion chamber 32, Two examples of structure
for a high pressure fluid distributor 74 or 74' shown in the
drawing, one example being illustrated in Figures 2 through 11
and the other example being illustrated in Figures 12 through
13.
In the first example of structure, best depicted in
Figures 2, 3 and 10, the fluid distributor 74 consists of a
long main tubular element 76 interconnected at one of its ends
to a high pressure pump 78. The high pressure pump 78 draws
recycled cleaning fluid from the fluid recirculating apparatus
66 and pressurizes the fluid to a pressure of 45 to 50 prig.
The fluid distributor 74 further has a series of '
spray nozzles 80 permitting the pressurized fluid within the
tubular element 76 to exit the element 76 in the form of sex-
oral high pressure streams. The spray nozzles 80 are chosen
so as to deliver a high pressure and high slow spray of
cleaning fluid into the immersion chamber. From the preferred,
embodiment, the nozzles have apertures of about one quarter
of an inch (.25"). Additionally, the fluid distributor 74 has
several tubular arms aye through 82d interconnected with the
-tubular element 76 and extending radially therefrom. Add-
tonal spray nozzles 80 are provided at the end of each of the
arms aye through 82d. The cleaning fluid from -the distributor
- 12 -
74 thus agitates the cleaning fluid in the immersion chamber
32. The agitated cleaning fluid scrubs the surfaces of the
receptacles 12 to remove dirt from the surfaces.
The second example of structure for a distributor
74' is shown in Figures 12 and 13 . AS with the distributor
described above, the distributor 74' has several radial arms
aye through 82'd interconnected with a long main element 76'
Each of the arms aye through Ed is provided with a spray
nozzle 80' to agitate the cleaning fluid. Additionally, the
distributor 74' has several Lo shaped arms aye through 83d
interconnected with the element 76' and each provided with a
spray nozzle 80' The various locations and orientations of
the nozzles will depend on the size and shape of the article
to be cleaned and the surfaces which must require scrubbing.
The majority of dirt on the receptacles 12 has been found on
the side walls aye through 16d. The hardest part of the dirt
to remove, however, has been found to be on the bottom wall
14 . A substantial number of the nozzles 80' are therefore
located below the receptacle 12. The spray nozzles 80' that
are directed towards the bottom wall 14 of the receptacle 12
from the distributor 74' are upstream of the spray nozzles 80'
on the arms aye through 83d and therefore create more turbo-
fence due to their greater pressure.
A heating apparatus (not shown) may also be provided
within the immersion chamber 32 to heat the cleaning fluid to
a predetermined temperature, preferably in the range of 150-
160F. Appropriate heating apparatuses are commercially
available and are well known to those skilled in the art.
The details of the rinse chamber 34 are best shown
in Figures 1, 3, 4 and 6; As shown in Figure 4, the rinse
chamber 34 contains a second spray tunnel or assembly 84 semi-
far to the first spray assembly 44 described in the prewash
,/( ~,~
- 13 -
I
chamber 30. The second spray assembly 84, as shown in Figure
6, has a pair of tubular end frame members 86 which are
arranged to form an open rectangle and several tubular cross
members 87 which are mounted longitudinally between the tub
far end frame members. The second spray assembly 84 is sup-
plied with fluid by a high pressure pump 88 which receives
rinse water withdrawn from a tank 90. A plurality of spray
nozzles 92 are mounted to the cross members 87 so as to direct
a plurality of high pressure spray jets of rinse fluid into
the second spray assembly 84. Those skilled in the art will
recogrlize that the rinse water in the tank 90 must be sepal
rated from the cleaning fluid in the tank 70 by a wall. The
rinse fluid from the second spray assembly 84 is sprayed onto
the receptacles in the rinse chamber 34 a-t a pressure of 70 to
80 prig from the pump 88 in order to remove the remaining dirt
and residual cleaning fluid from the receptacles. The pro-
furred pressure is 75 prig. Thus, the high pressure rinse
fluid spray jets produce high velocity streams which mechanic
gaily scrub the remaining dirt from the objects and rinse any
residual cleaning fluid adhering to the objects. The fluid it
the tank 90 may be heated by any convenient conventionally
available heater member. The removal of liquid from the
objects after they have passed through the rinse chamber 34
may be accomplished by a fan 94 (Figures 3 and 4) which blows
air (shown only in Figure 3), optionally heated, over the
receptacles.
The receptacles 12 to be cleaned are to be entirely
immersed in the cleaning fluid in the immersion bath in order
to loosen all the dirt from the surfaces of the object to be
cleaned. In order to achieve this with dirty objects which
are less dense than water, such as plastic receptacles 12, a
mechanical guidance system is provided to insure that the
- 19 -
~21~3~
objects to be cleaned are held entirely below the surface ox
the cleaning fluid during their passage through the immersion
chamber 32. The receptacles may be directed through the ape
fetus 10 along a guide assembly 96 (best shown in Figure 2).
The guide assembly 96 extends serially through the prewash
chamber 30, through the immersion chamber 32 and through the
rinse chamber 34.
The guide assembly 96 has two lower guide rails aye
and 98b arranged in a spaced apart relationship to each other
and adjacent to the opposite sides of the guide assembly 96
(Figures 2 and 4). The lower guide rails aye and 98b extend
first horizontally to the prewash chamber 30, then angularly
downward to the entrance of the immersion chamber 32 to direct
the objects downwardly below the level of the cleaning fluid
in the immersion chamber 32. Adjacent to the bottom of the
immersion chamber 32, the lower guide rails aye and 98b extend
first horizontally and then angularly upwardly through the
passage 43 in the wall 42. Finally, the lower guide falls aye
and 98b extend horizontally through the rinse chamber 34.
The guide assembly 96 also includes two side support
rails loo and loo arranged opposite to each other, above the
lower guide rails aye and 98b and at opposite sides of the
receptacles 12. These side support rails loo and loo extend
through the prewash chamber 30, through the immersion chamber
32 and through the rinse chamber 34 in a similar way as the
lower guide rails aye and 98b. The guide assembly 96 also
includes a pair of top guide rails aye and 102b which era
arranged opposite each other above the side support rails loo
and loo and at opposite sides of the guide assembly 96. The
top guide falls aye and 102b extend through the prewash
chamber 30, immersion chamber 32 and rinse chamber 34, in a
similar way to the side support rails loo and loo.
- 15 -
so
A conveyor assembly 54 is mounted in the housing.
The conveyor assembly 54 extends horizontally into and through
the prewash chamber 30, the immersion chamber 32, and the
rinse chamber 34. The guide assembly 96 receives dirty recap-
lades 12 placed thereon by an operator or by another conveyor
(not shown). The conveyor assembly 54 pushes each receptacle
12 along the guide assembly 96 and maintains the receptacles
12 in a longitudinal spaced apart relationship. The
longidutinal spacing of the receptacles 12 permits the high
pressure spray jets of the cleaning fluid in the prewash
chamber 30 and of the rinsing fluid in the rinse chamber 34 to
impinge on the leading and trailing side walls aye and 16c of
each receptacle. furthermore, the angular spacing ox Audi-
cent receptacles (see Figure 4) passes through the scrubbing
station and permits the turbulent cleaning fluid therein to
better scrub the leading and trailing side walls aye and 16c.
Details of the conveyor assembly 54 may be seen in
Figure 1 through 3. The conveyor assembly 54, shown in the
. drawing, is well known in the art and is available common-
Shelley. while other means for conveying the receptacles thereof the housing are possible, the conveyor assembly 54
preferred. The conveyor assembly 54 has two tracks aye and
55b, each extending through the prewash chamber 30, the
immersion chamber 32 and the rinse chamber 34 on opposite
sides of the guide assembly 96. The conveyor assembly 54 also
has two continuous chains 56, one for each of the tracks aye
and 55b. Each of the chains 56 (only one of which is shown,
in part, in the drawings) extends from a drive mechanism (not
shown) along the entire length of one of the tracks aye or 55b
through the housing 11 and returns also in a manner well known
in the art, but not shown in the drawing, to the drive mocha-
noisome. The conveyor assembly 54 further has several push rods
16 -
53~
I extending between the two continuous chains 56. The push
rods are spaced apart a predetermined distance exceeding the
length of the receptacles 12. the receptacles 12 are deli-
eyed to the conveyor assembly I in a manner such that one
receptacle is provided between each adjacent pair of push rods
58 and is pushed along the guide assembly 96 by the push rod
I adjacent to the trailing side walls 16b of the receptacle.
operation
On operation, a batch of dirty receptacles 12 are
Lo delivered to the inlet passage aye of the cleaning apparatus
10. The conveyor assembly 54 serves to space the dirty
objects from one to the other so that high pressure spray of
the first spray assembly 44 can be applied directly to the
entire surface of each receptacle 12 including the leading
sidewall (wall aye in Figure 2) and the trailing sidewall
(wall 16c in Figure 2) thereof. Thus, the scrubbing action of
the high pressure spray jets impinging on the surface of the
receptacles, combined with the chemical action of the cleaning
fluid acts to loosen or remove a portion of the dirt from the
receptacles.
The receptacles 12 are directed by the conveyor
assembly 54 from the prewash chamber 30 into the immersion
chamber 32 and are guided along the guide assembly 96
there through. In the soaking station 60 of the immersion
chamber 32, the heated cleaning fluid reduces the surface ten-
soon of the dirt and of the dirty receptacle. The cleaning
fluid within this initial portion of the immersion chamber 32
is not agitated for reasons that will become apparent shortly.
The receptacles 12 are directed by the conveyor
assembly 54 from the soaking station 60 into the scrubbing
station 62 of the immersion chamber 32. In the scrubbing sty-
lion 62, the cleaning fluid is agitated to scrub the surfaces
- 17 -
I I
of the receptacle 12. The cleaning fluid may be agitated to
such an extent that large pieces of debris such as straws,
broken glass and caps will be removed from the receptacles.
Preferably, the nozzles 80 of the fluid distributor
in the scrubbing station of the immersion chamber 32 are
adapted to agitate only the final half or final third of the
immersion chamber.
This is done since the scrubbing action of turbulent
cleaning fluid in the initial portion of the immersion chamber
32 is less effective than the scrubbing action of turbulent
fluid in the final portion of the immersion chamber. During
the time that the receptacle 12 is in tune soaking station of
the immersion chamber, the cleaning fluid acts to reduce the
surface tension holding the dirt to the receptacle. Heating
the cleaning fluid, referred to earlier by means of a heating
apparatus in the immersion chamber 32, assists in this process
and reduces the time necessary for the cleaning fluid to act
on the dirt and the surface of the receptacle. Once the sun-
face tension has been reduced, the turbulent cleaning fluid
will quickly and efficiently scrub the dirt from the Rosetta-
ale. Thus, for the same amount of flow and pressure delivered
by the pump 78, a better cleaning result is obtained by having
spray nozzles 80 only in the final portion of the immersion
chamber 32.
The receptacles 12 are finally directly by the con-
voyeur assembly 54 from the immersion chamber 32 into an
through the rinse chamber 34 where the entire surface of each
receptacle 12 is rinsed by the high pressure spray of the
second spray assembly 84.
It is therefore readily apparent that the present
invention provides an economical cleaning method and apparatus
for cleaning dirty objects. The method and the apparatus
- 18 -
described are particularly of value for high volume situations
where a substantial number of dirty objects must be rapidly,
reliably and economically cleaned. The method and the appear-
tusk combine chemical and mechanical cleaning techniques in an
efficient manner to minimize the amount of caustic chemical
that must be used for cleaning the objects. The method and
apparatus are therefore adapted for cleaning dirty objects
including materials which cannot withstand the use of harsh
cleaning fluids. Finally, the method and the apparatus pro-
vise a means for reliably cleaning all surfaces of the dirty objects and for removing pieces of debris from within the ox-
jets.
-- 19 --
