PROCESS AND APPARATUS FOR PRECISION FILLING OF CONTAINERS

METHODE ET DISPOSITIF DE REMPLISSAGE DE PRECISION POUR RECIPIENTS

English Abstract

TITLE
Process and Apparatus for
Precision Filling of Containers
ABSTRACT
A process and apparatus for the precision
filling of containers used in combination with a
convention filling equipment: tare weigh of the
container is determined, the container is initially
filled with material and then weighed; a computer is
fed the tare weight data and initial fill weight data
and calculates the precise amount of material to be
added to bring the container to its content weight
and then a positive displacement pump driven by a
servo motor controlled by a servo control connected
to the computer adds the exact amount of material to
the container. The process and apparatus are
particularly useful in a paint filling line.

Claims

The embodiments of the invention in which an
exclusive property or privilege is claimed are
defined as follows:
1. A process for precision filling of
containers with liquid material to an exact content
weight used in combination with conventional filling
equipment having a material reservoir and having an
initial filling station, a digital control computer,
first and second weighing stations each electrically
connected to the computer and a final filling station
tubularly connected to the reservoir and fed by a
constant displacement gear pump coupled to a servo
drive motor which drives the pump and servo
controller electrically connected to the servo drive
motor and connected to the computer which process
comprises the following steps:
(1) placing an empty container in the
first weighing station and measuring
the tare weight of the container and
feeding the tare weight to the
computer;
(2) shifting the container to the inital
filling station and filling the
container with material within 10% of
the exact content weight of the
container;
(3) shifting the container to the second
weighing station and measuring the
weight of the container and feeding
the resulting weight to the computer;
(4) shifting the container to the final
filling station and filling the
container to the exact content weight
by adding a precise amount of material
as determined by the computer to the
container by the constant displacement
pump.

2. The process of Claim 1 in which the
material is a paint.
3. The process of Claim 2 in which the
final filling station has a non-drip solenoid
activated dispersing valve.
4. An apparatus for precision filling of
containers with material used in combination with
conventional filling equipment having a material
reservoir and having an initial filling station; the
apparatus comprises:
(1) a digital control computer;
(2) first and second weighing stations
each electrically connected to the
computer,
(3) a final filling station tubularly
connected to the reservoir
(4) a constant displacement gear pump
tubularly connected to the reservoir
and final filling station;
(5) a servo drive motor coupled to the
gear pump and which drives the gear
pump, and
(6) a servo controller electrically
connected to the servo drive motor and
to the computer and which controls the
servo drive motor.
5. The apparatus of Claim 4 in which the
final filling station has a non-drip solenoid
activated dispensing valve.
6. The apparatus of Claim 4 in which the
material is paint.

Description

~3~
TITL~
Proce~s and Apparatus for Preci6ion
Pilling of Con~ainers
BACKGROUND QF THE INVENTION
Thi~ in~en~ion i8 rela~ed to a proce6s and
~ppara~us for precision filling of containers.
One problem ~hat ha~ plague~l industry i~ the
filling of cont~iner~ with ~he e~ac~ amount o~
~at~rial a6 6ho~n on t~e label of ~h~ contai~er.
U~derfilling of container~ viola~ion of laws
and can result in ~ubstan~ial fine and ~ive6 the
manufacturer a poor reputation. One traditio~al way
to oYercome the under illing problem i6 ~0 ov~xfill
con~ainer by about 0.5-1%. While this is acceptable
to the con~u~er, the manufacturer sustain6 a direct
106s 0~ profit on Pach container by the amoun~ of
overfill.
The proces~ and apparatus o~ thi~ invention
pro~ide6 ~or the exact filling of ~ontainers ~d
pre~ent~ underfillin~ and profit 108~e8 due ~o
overfilling of ~ontainers.
SUM~ARY ~F THE INNENTION
A p~o~e~s and ~pparatus ~or ~recision
~illing oP co~tainers ~ith ~aterial used in
co~binatio~ wit~ co~ventional ~illing equipment
havi~g a materîal re~erYoir and haYing an ini~ial
fillin~ station, a control ~omput~r, fir~t and ~e~ond
w~lghing statio~s each ~lectrically connec~ed to ~he
computer and a ~in~ g ~t~tion tubularly
conn~cted ~o the reservoir and fed by a ~o~tant
di~placement pump having driving and control ~ean~
~ontolled by ~he computer; ~hich process ~omprises
the following ~teps:
(1~ placing an ~mpty co~tainer i~ the first
wei~hing station and mea6uring ~e tar2

weight of the container and feeding ~he
reæulting weight data to the computer,
(2) ~hifting the contai~er to ~he initial
filling ~a~ion and filli~g the
con~ainer wi~h ma~erial within 10% of
i~s ~otal weight:
(33 ~hifti~g the filled container to the
second w~ighing &ta~ion and mea~uring
it8 weight and ~eedin5~ the re~ulting
weight da~a to ~he computer;
(4) shifting the filled con~ainer to the
final filli~g 6tation and ~illin~ the
container o it~ exact conten~ weight
by adding the preci~e amount of
ma~erial a~ de~ermined by the computer
and fed ~o the container by the
con~tant displacement pump.
BRIEF_D~SCRIPTION_OF THE D AWING
The ~IG is a ~chematic repre~entation
illu6trati~g the major co~ponent6 o~ the apparatus of
thi~ inYention.
DETAI~LED DESCRIPT ON OF THE INVENTION
Thi~ invention is directed ~o a proces~ and
appara~u6 for preci~ion ~illing of ~ontainer~ wit~
~aterial. The procs6s a~d apparatu6 can b~ used for
all types of liquids, e.~., 601ution6, dispersion,
and lati~eæ. The proce6~ and apparatus is
particularly designed for u6e i~ illi~g of
containeræ with paint~.
In the proce66 of ~his inventio~ ~Ref
to FIG~, conventional paint filling machine 1 ~hown
in box of broken line) i~ u~ed. The fill~g ~achine
has a r~6ervoir 2 and an in;~ial fill control
~echa~i~m 3~ I~ a ~onventional paint ~illin~

proce6~, a ~ontainer i6 pla~ed in ~he ~ni~ial fillin~
s~a~ion 4 and f illed bu~ h a ~ligh~c exces~ OI
paint. The filled con'cainer6 weigbt i~ E~ea~ured and
if ~he container i6 under weight, 6hnnted off the
filling line and ~chen manually ~illed ~o i.'C8 proper
weight .
In tlle proce~6 of 'chi6 inverltion, tare
weigllt oî a con~ainel is mea6ured at ~he fir~
weighing 6tatiDn 5. The re~ult~ng weight data i~ fed
~co a control compu~er 6. A typical ~reight mea~uring
in6~rument ~l6ed at tl~e f ir~t weighiny ~eation i~ El
~etrama~i~ Co. check weigherO
The control computer 6 ~cypically i~ a
digi~al compu~r ~uch a~ an Intel SE~C 80~10~* Other
computer~ and microproces~or6 al80 ~an be u6ed.
A~ter tlle tare ~eight of the container ha~
been mea~ured, the conta`; ner i6 ~if ted via a
conventivnal filling line to the initial iEilling
~tation and ~illed within 10~ of it6 total ~eight and
u~ually within about 1-10~ of it8 total ~eight. ~he
contai~er then i~ 6hifted to ~he ~econd wei~hi~g
station 7 and the initial fill ~eight i~ mea6ured
and the re6ulti~g weight data i8 fed to ~he ~omputsr
6. The ~ame ~ype of weighing eguip~ent i~ ~6ed a~
u~ed in the f ir8t weighi~ 6ta~io~.
The eontainer then ~B 6hiPted to the final
filling station 8 and the container ~hen i6 fill~d
with ~he exact amount o~ paint reguired in the
containeE~ Thi6 i6 acco~pliæhed by ~ con~ant
di~placement pump 9 ~hich i~ tubularly ~3~nect~d to
~he paint r~ervoir 2 and driv~ by a ~ervo drive
motor 10 coupl~d to the pu~p. T~ ~ervo drive ~otor
10 i6 controlled by a 6ervo controller 11 directly
conneeted ~o the compu~r 6.
* denotes trade mark

~3~
The eosnRu~r 6 frv~ t~ afox~loe~io~ed
~eigh~ da~a deterr~ine~ ~he a~ount ~f paint to be
added ~co ~he contai3ler. Tlhis i6 ao~e ~y le~e co:npu~er
ooinpariDg tlle data from ~he ~cond weig~ g ~tatior~,
and ~are weig~ data and ~e~ cal~ at~g k~e
additio~ of the require~ ~?eight o paint t~a~ the
eo~cainer ~DUSt ~ontain. Ttli6 ~al~ulated weig~ o~E
pai~t to be a~de~ i~ eo~vert~d to a ~rolu~e ~ddi ion
by tak~ ng in'co account lthe ~ensity of ~he pain~ alld
~hen ~6 conver~e~ l~o an el~eE~cal 6ignal by ~he
~ss~puter and i6 ~d to the ~ervo controller 11 which
allow~ ~he servo ~rive ~o~or 10 to ~rive th~ ~onstant
di~place~ent pump 9 e~e exa~t aumber of ~evolutiosl~
~o add the required weight of paint to the eontainer.
~ ~ypical servo controller that can be u~ed
i6 an Indu6trial I~dexi~g 6y6tem PSC 100 in
comblnaSlon with an Inland*~P/2~ 22-5152
a~plifier. A ~ypiGal ~ervo drive ~0~9r ~6 an Inland*
TT 4202 ~otor and the pu~p i~ typically a gear pump
~ade by Zenit~ ~anufacturi~g ~o~pany typ2 BLB5456-20.
It ~ preferred to u~ a no~-drip ~alve 12
~ubularly connected to the ~u~p 9 at t~e f~al
filling ~tatio~ to preven~ exce66 pai~ ~ro~ beinq
di6pen~d. One ~ypical valve is a ~mall orifi~e
dissharge solenoi~ ~alYe. Typicall~, ~his valve i~ a
601eno~d valve ~odel 300~27 ~anufactured by
Spraymation I~c. The 6mall orifice o~ tbe ~alve
i~rea6e~ t~a exit velocity of tha material ~.2.,
paint being pu~ped ~nto ~e ~on~ainer an~ eli~ina~6
r~sention o ~he ma~rial i~ or on ~he valve ~nd
0r~e6 t~e ~a~erial l~to the ~e~6el. The ~alve ~
~oupled ~o the ~ervo controller 11 whi~h opens tbe
val~e whe~ ~aterlal i6 being ~umped ~to the
eont~iner ~D~ i~media~ely ~106e6 t~e valve v~en
pumping ~top~ to preven~ lea~age of material to ~he
~ontainer.
* denote~ trade mark