U.S. patent number 3,578,041 [Application Number 04/761,441] was granted by the patent office on 1971-05-11 for automatic apparatus for packaging powdered material with uniform bag weight and with dust-free operation.
This patent grant is currently assigned to Nippon Jido Fukurozumeki Mfg. Co., Ltd.. Invention is credited to Katsuji Obara.
United States Patent |
3,578,041 |
Obara |
May 11, 1971 |
AUTOMATIC APPARATUS FOR PACKAGING POWDERED MATERIAL WITH UNIFORM
BAG WEIGHT AND WITH DUST-FREE OPERATION
Abstract
An automatic packaging apparatus for powdered material in which
such material is fluidized in an air chamber and delivered by air
to a filling means associated with a receiving bag. Flow control
means are provided responsive to automatic weighing means, and
recirculation means are provided for returning the dust from the
air chamber and the region of the filling means for
recirculation.
Inventors: |
Obara; Katsuji (Yokohama,
Kanagawa, JA) |
Assignee: |
Nippon Jido Fukurozumeki Mfg. Co.,
Ltd. (Tokyo, JA)
|
Family
ID: |
25062194 |
Appl.
No.: |
04/761,441 |
Filed: |
September 23, 1968 |
Current U.S.
Class: |
141/59; 141/128;
141/68; 141/317 |
Current CPC
Class: |
B65B
1/18 (20130101) |
Current International
Class: |
B65B
1/04 (20060101); B65B 1/18 (20060101); B65b
001/18 (); B65b 001/34 () |
Field of
Search: |
;141/67,68,59,128,317 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Myhre; Charles J.
Claims
I claim:
1. An automatic packaging apparatus for powdered material, said
apparatus comprising a hopper for containing such material, a
chamber disposed beneath said hopper, said chamber being provided
in its upper portion with an air exhaust outlet for discharging air
therefrom after packaging has been finished and at its lower
portion with air inlet means for blowing air into said chamber to
fluidize said material moving therethrough, a housing arranged
beneath the bottom of said chamber, said housing being provided
with a second air inlet means for admitting air into said housing
for fluidizing the material delivered thereto, said housing being
provided at a point above said second air inlet means with an air
supply pipe for urging the fluidized material through and out of
said housing, feed pipe means connected to and communicating with
said housing for receiving material moved by said air supply pipe,
flow control means connected to said feed pipe means for
controlling the rate of flow of the material through said feed pipe
means, filling means associated with said flow control means for
discharging the material into a bag, automatic weighing means
operatively connected to said flow control means to selectively
regulate material flow according to bag weight whereby a plurality
of bags may be filled to a uniform weight, and means for feeding
dust in said chamber and at said filling means back into said
hopper for recirculation of said dust.
2. Apparatus according to claim 1 wherein each of said air inlets
comprises a casing which is provided at one side with an air
pervious pad and at the other side with an air supply pipe of large
diameter and an air exhaust pipe of small diameter for relieving
air pressure both in the chamber and in the housing.
3. Apparatus according to claim 1 wherein said air exhaust outlet
comprises an air exhaust pipe of large diameter and a cleanout pipe
of small diameter, which are connected to two flexible coupling
pipes of different diameters which can be pinched alternately by a
flow cutoff arrangement.
4. Apparatus according to claim 1 wherein said flow control means
comprises a control pipe of large diameter for full flow of the
material to be packaged and a control pipe of small diameter for
dribble flow of the material, both of said control pipes being
connected to a manifold by two flexible coupling control pipes of
different diameters which can be pinched alternately by a flow
cutoff control arrangement.
5. Apparatus according to claim 4 wherein the entrance to said
control feed pipe for dribble flow is provided with a grid screen
for preventing passage of large particles of the material through
said control feed pipe.
6. Apparatus according to claim 1 wherein said filling means
comprises a discharge spout connected to said flow control means by
a flexible coupling, for discharging the material into a bag, an
outer sleeve surrounding said discharge spout for providing an air
exhaust path, the end of said outer sleeve being provided with a
filtering mesh for releasing air from the bag while preventing
escape of the material therefrom, and an air cleanout pipe in the
outer sleeve for cleaning said filtering mesh.
7. Apparatus according to claim 6 wherein said outer sleeve is
provided around a portion of its outer periphery with an expansible
membrane whose interior communicates with an air supply pipe for
sealing the inlet of the bag airtightly during filling of the
bag.
8. Apparatus according to claim 1 wherein said automatic weighing
means comprises a seat for a bag, a weighing mechanism including a
main balancing weight somewhat lighter than a predetermined desired
filled bag weight and an auxiliary weight for balancing the
predetermined bag weight, detecting means operative just before the
predetermined bag weight is attained, and means for temporarily
stopping the auxiliary weight at a certain level.
9. Apparatus according to claim 1 wherein said dust feeding means
has an upper cylindrical portion, to which dust conduit means for
each air inlet and from the filling means are connected and a
conical lower portion to which an air supply pipe is connected, an
opening in the lower end of said lower portion being connected to a
feed back conduit loading to said hopper.
Description
BACKGROUND OF THE INVENTION
This invention relates to an automatic apparatus for packaging
powdered materials such as carbon black, starch, wheat flour, fly
ash, powdered synthetic resin, diatomaceous earth, fertilizer and
other chemical by-products, with uniform bag weight and with
dust-free operation, while in a fluidized state of the
materials.
According to the packer heretofore used, an uniformity of the bag
weight is not obtained due to the difficulties in the fine bag
discharge of the material to be packaged.
Further, the air impervious bags such as polyethylene, polyvinyl,
vinyl bags or laminated paper bags, for example, are used to
prevent the packaged material from being moistened. According to
the conventional apparatus of this class, however, the quick
filling of the material into such air impervious bags cannot be
achieved since the material escapes outside through the clearance
formed between the discharge spout and the inlet of the bag.
SUMMARY OF THE INVENTION
It is, therefore, a principal object of the invention to eliminate
the above difficulties and disadvantages and to provide a new
automatic apparatus for packaging powdered material with accurate
and uniform bag weight and with dust-free operation, which enables
the accomplishment of such packaging even for the air impervious
bag with a high filling speed.
Another object of the invention is to provide an automatic
apparatus for packaging powdered material with uniform bag weight
in which means for filling the material is provided with a flow
control system which comprises two feed pipes having different
diameters, i.e. one for the full flow and the other for dribble
flow so that the flow rate of the material at the final step of the
packaging is finely controlled.
Still another object of the invention is to provide an automatic
apparatus for packaging powdered material with uniform bag weight
in which an open end of the feed pipe of smaller diameter for
dribble flow of the material is covered with a grid screen to
prevent the said feed pipe from being plugged.
Yet another object of the invention is to provide an automatic
apparatus for packaging powdered material with uniform bag weight
in which means for filling the material at its open end is provided
with a mesh means so that the air discharged into the bag together
with powdered material may be exhausted through an exhaust pipe
connected to the said filling means of the material.
A further object of the invention is to provide an automatic
apparatus for packaging powdered material with uniform bag weight
in which an outer periphery of the filling means at its base
portion is provided with a retractable valve means into which an
air supply pipe is connected so that the clearance formed between
the filling means and the inlet of the bag may be sealed airtightly
when the said valve means is expanded by the air supply.
Still a further object of the invention is to provide an automatic
apparatus for packaging powdered material with uniform bag weight
in which a weighing system comprises a main balance weight means
and an auxiliary balance weight means which are cooperative with
the flow control means consisting of two feed pipes of different
diameters to ensure a highly accurate weighing.
And a further important object of the invention is to provide an
automatic apparatus for packaging powdered material with dust-free
operation and a high filling speed in which air exhaust means are
connected to the aerator units arranged at the lower inclined
periphery of the air chamber and at the bottom of the housing, and
to the filling means and are assembled into the dust collecting
means which communicates with the upper serge bin so that all the
leaked dusts are perfectly fed back by the circulation system.
These and other objects and advantages of this invention will
become readily apparent and be understood from the following
description and the accompanying drawings in which the same
reference numerals designate the same or similar parts throughout
the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the automatic apparatus for packaging
powdered material with uniform bag weight and dust-free operation
according to the invention;
FIG. 2 is a pictorial view illustrative of the operation of the
pinch air exhaust device according to the invention;
FIG. 3 is a fragmentarily enlarged front view of the aerator units
according to the invention;
FIG. 4 is a fragmentarily enlarged perspective view, partially
broken away, of the housing in which an entrance of the feed pipe
of the smaller diameter for dribble flow is coated with a grid
screen;
FIG. 5 is a fragmentarily enlarged sectional view of the flow
control system comprising the two feed pipes with pinch couplings
of different diameters;
FIG. 6 is a pictorial view illustrative of the operation of the
flow control means of FIG. 5 showing the larger coupling being
squeezed shut, while the smaller coupling is being opened;
FIG. 7 is a fragmentarily enlarged cross sectional view of the
filling means according to the invention;
FIG. 8 is a fragmentarily enlarged cross sectional view of the
filling means of another embodiment according to the invention
which is provided at its base periphery with a retractable valve
means for airtightly sealing the clearance to be formed between the
filling means and the inlet of the bag;
FIG. 9 is a fragmentarily enlarged sectional view of the dust
collecting means according to the invention; and
FIG. 10 is a pictorial view of the weighing means according to the
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, the powdered material is charged into the serge bin 1
and subsequently the material in a suitable amount is dropped into
the air chamber 3 by opening a cone valve 2.
At the inclined outer periphery of the air chamber is provided four
aerator units 5 for fluidizing the powdered material in the air
chamber 3. These four aerator units may be replaced by two or three
units in order to achieve fluidization of the material to be
packaged.
The compressed air supplied through an air pipe 6 is introduced
into an intermediate chamber 7 and then blown into the air chamber
3 through an air-pervious pad 8 to fluidize the material in the air
chamber. In this event, the powdered material is directed
downwardly by the convection of the air into the housing 4
connected to the lower end of the air chamber 3.
A further aerator unit 9 is provided at the bottom of the housing 4
to receive the powdered material shifted from the air chamber 3 in
fluidized state.
An air supply pipe 11 enters one side of the housing 4, through
which a jet air is supplied into the housing so that the powdered
material floating within the housing by an action of the aerator 9
is urged into the feed pipe 17 of a smaller diameter for dribble
flow of the material.
In the air chamber 3 as well as the housing 4 an air inflow through
the pads 8 and 10 is continued even after the air charge exceeds
the allowable limit, so that the powdered material is bound or
bridged under the extensive air pressure increasing the air
pressure more and more with increase of the coagulation of the
material, and as the result the performance of the packer is
remarkably reduced.
According to the invention, the exhaust pipes 12 and 13 are
connected to the aerators 5 and 9 to relieve the pressure in the
air chamber 3. The other ends of the exhaust pipes 12 are connected
to an intermediate pipe 14 surrounding the aerator 5, which is
further connected to a main conduit 15 communicating with the dust
collecting means hereinafter illustrated.
The other end of the exhaust pipe 13 is connected to the
intermediate pipe 14 communicating with the main conduit 15.
By this construction, excessive air permeates through the inclined
air-pervious pads 8 and 10 stretched between the air chamber, the
housing and the aerator units and is directed to the exhaust pipes
12 and 13 together with the dust and then collected into the dust
chamber 33. Accordingly, the air-pervious pads do not prevent
blocking the dust.
In FIG. 5, the flow control system comprises the feed pipe 16 of
the larger diameter for the full flow of the material and the feed
pipe 17 of smaller diameter for the dribble flow of the material
which is provided with a detachable fitting 18 having a conical
orifice. The inner diameter of the fitting 18 may be optionally and
suitably determined in accordance with the particle size of the
material to be packaged.
As is shown in FIG. 4, the entrance of the feed pipe 17 for the
dribble flow is coated with a grid screen 19 to stop any inflow of
the crude particles which are likely to clog the orifice of the
feed pipe 17.
In case no such grid is provided in front of the entrance of the
smaller feed pipe 17, a separate filtering means must be added to
the packer in order to remove the crude particles, which increases
relatively the cost of the apparatus.
The feed pipes 16 and 17 of different sizes are connected to a
manifold 22 by the pinch couplings 20 and 21 and the manifold 22 is
connected through a flexible tube 23 to a discharge spout 26.
The flow control system cooperates with the weighing system, and
immediately before the powdered material packaged in the bag comes
to the predetermined bag weight, the pinch coupling 20 of the
larger diameter is squeezed shut by the cutoff device of known
construction to close the feed pipe 16 for the full flow, while the
pinch coupling 21 of the smaller diameter being opened to permit a
dribble flow of the material as is shown in FIG. 6. When the
material in the bag comes to the predetermined weight, the pinch
coupling 21 of smaller diameter is squeezed shut to close the feed
pipe 17 for dribble flow, so that the packaging operation is
carried out under the uniform and accurate bag weight control.
In FIG. 7, the filling means 24 is secured to a flange 25 bearing a
bag seat 40.
The filling means 24 comprises a discharge spout 26 and an outer
sleeve 27. An open end of the outer sleeve 27 is provided with a
mesh filter 28 such as the wire screen or cloth of mesh size
corresponding to the particle size of the powdered material to be
packaged. To the lower periphery of the outer sleeve 27 is
connected an air exhaust conduit 29.
The powdered material discharged together with the air flow is
precipitated in the bag 39, while the air is exhausted through the
mesh filter 28 and the outer sleeve 27 to the exhaust conduit 29.
In this case, some dust is exhausted together with the air flow,
which is subsequently directed to the exhaust conduit 29 and
collected in the dust chamber 33, so that any leakage of the dust
from the apparatus may be prevented.
According to this construction, an automatic packaging of the
powdered material into the air impervious bag may be effected with
a higher speed as compared with the conventional packer. In the
outer sleeve is arranged an air cleanout pipe 30 for cleaning the
mesh filter 28 to prevent any clogging thereof.
In FIG. 8, the outer sleeve 27 at its outer periphery is provided
with a retractable valve 31 to which an air supply pipe 32 is
connected. After the insertion of the filling means 24 into the
inlet of bag 39, the air is supplied into the retractable valve 31
to expand the same spherically as is shown in FIG. 8 so that the
clearance formed between the inlet of the bag 39 and the filling
spout 24 is sealed airtightly to inhibit any leakage of the
material. The air supply pipe 32 is reversible and after the
packaging operation is finished, the air in the valve 31 is
exhausted through the air supply pipe 32 to retract the valve 31 to
the original flat state.
The dust collecting means comprises a drum chamber 33 having a
conical lower portion, with which the main conduit 15 leading from
the aerator units 5 and 9 and the exhaust conduit 29 from the
filling means 24 are communicated as is shown in FIG. 9. An air
supply pipe 34 enters the chamber 33 to urge the dust fed by the
main conduit 15 and the exhaust conduit 29.
The dust chamber 33 at its lower portion is connected to a feed
back conduit 35 and the other end thereof is communicated with the
serge bin 1. Accordingly, the dust collected in the chamber 33 is
fed back to the serge bin 1 without leakage and charge again into
the air chamber 3.
The air pooled in the serge bin 1 is discharged to the atmosphere
through an air vent 39 provided with a filter means and after the
packaging operation the air in the air chamber is exhausted through
the exhaust pipe 37 and fed to the serge bin 1.
As is shown in FIG. 2, the exhaust pipe 37 is provided with an
auxiliary cleanout pipe 38, so that when a flexible coupling 37a is
squeezed shut by the cutoff device of known construction, a pinch
coupling 38a is opened to supply the air through the cleanout pipe
38 whereby to clean the inside of the exhaust pipe 37. On the other
hand, when the coupling 37a is opened to exhaust the air in the air
chamber, the pinch coupling 38a is squeezed by means of the cutoff
device such as the air cylinder.
A bag seat 40 is surmounted with the bag 39 for containing the
powdered material and when the powdered material in the bag comes
to the predetermined bag weight, the weighing means cooperates with
the flow control system to ensure the packaging with uniform and
accurate bag weight.
The weighing means comprises the bag seat, balance weighing
mechanism and detecting means FIGS. 1 and 10), and the seat 40 is
shifted downwardly in proportion to an increase of the filling of
powdered material material into the bag 39. In this case, the
filling means 24 is bent downwardly in accordance with the downward
movement of the weighing seat 40 since the weighing seat 40 and the
filling means 24 are integrally secured to the flange 25.
The downward movement of the weighing seat 40 is transferred
through the flange 25, a main lever 41, a draft rod 42, an
extension lever 43 and a draft rod 44 to a scale beam 45 of the
balance weighting system (A) to raise the right-hand end of the
said scale beam 45. The left-hand end of the scale beam is provided
with a center weight 46 to inhibit any oscillation of the scale
beam.
The scale beam 45 at its right-hand side is provided with an
exchangeable main weight means 48, which is somewhat below the
predetermined bag weight, through a suspension rod 47 which is
provided at its lower end with a collar support 50 for bearing an
auxiliary weight means 49 which satisfies the final bag weight.
In advance with the packaging operation, the right terminal of the
scale beam 45 is somewhat raised resisting the main weight means
48, so that a slit plate 51 fitted to the scale beam 45 actuates a
primary photoelectric detector 52 which cooperates with the flow
control system to pinch the coupling 20 of the feed pipe 16 for
full flow of the material. While during the operation of the
primary photoelectric detector 52, the collar support 50 is raised
to the level for receiving the bottom of the auxiliary weight means
49 lying on the floor flame 54 whereby to exert an additional
weight on the scale beam 45. Whereafter, the powdered material is
fed only through the small feed pipe 17 for dribble flow and when
the filling of powdered material comes to the predetermined bag
weight, the scale beam 45 is tilted to enable slit plate 51 to
actuate a secondary photoelectric detector 53 which cooperates with
the flow control system to shut the small feed pipe 17 whereby to
finalize the packaging operation.
In the weighing mechanism mentioned above, the operation of the
primary photoelectric detector 52 induces the starting of the timer
of the delay open relay circuit to energize a solenoid 55 which
makes a magnetic contact with one end of an auxiliary beam 56 to
fix the auxiliary weight means 49 on the floor 54 so that any
unnecessary suspension of the auxiliary weight means 49 by the
suspension rod 47 is positively suppressed.
As illustrated above in the packaging apparatus according to the
invention, the powdered material in the air chamber is sufficiently
fluidized in the air chamber without suffering any overpressure
problem and the flow rate of the material to be packaged is finely
and uniformly controlled by the combination of the flow control
system comprising the larger feed pipe for full flow and the
smaller feed pipe for dribble flow with the weighing system
comprising the main weight means and the auxiliary weight means,
which ensures the packaging operation with a highly uniform bag
weight with the maximum weighing error of 1/5000 which is an
amazing value as compared with those obtainable by the conventional
packaging apparatus of this class.
Further, according to the invention, a perfect dust-free operation
may be achieved since the dust is completely collected by the
circulation system.
It will be appreciated that in lieu of the aerator units arranged
at the conical lower portion of the air chamber, a vertical screw
conveyor can be disposed along the center axis of the air chamber
to convey the wet powdered materials such as salt, sugar and the
like into the housing, while satisfactorily stirring such wet
powdered material.
While certain preferred embodiments of the invention have been
illustrated by way of example in the drawings and particularly
described, it will be understood that various modifications may be
made in the apparatuses and constructions and that the invention is
no way limited to the embodiments shown.
* * * * *