Note: Descriptions are shown in the official language in which they were submitted.
A ~ETHOD AND APPA~TUS FS:)R
PRINTING WII~I PAINT
This invention relat~s to prin~ing by transferring
paint from a paint-lad~n design ~to the sur:fac.e of a dis-
tensible ~ransfer member and ~hence on~o ~he surface of an
article. More part.icularly, the present inven~ion relates
to a method and apparatus to transfer paint from a pattern
onto the surface of an ar~icle where the paint a~tains an
instant-dry state by cooling thereof or by treatment wikh
ultraviolet radiation.
As is known in the ~rt 3 pr:~nti.ng by gravure
includes etching a design or image in a plate which is sur-
ro~ded by side walls to retain a supply of a liquid solvent~
type paint~ The wet paint is spread across the surface of
the plate and then a doctox blade is used to clean the plake
surface so that only the etched .image is laden with paint.
A silicone rubber tr~nsf~r pad is pressed :~to contac~ with
the surface of the plate so that some of the paint :in the
image is earried by the pad onto the surface of an article
at a distally-spaced location. The solvent in the paint on
the surface of the article must be released to effect dryLng
of the paint. The wet paint is usually dried in an oven by
heating the container or only its surface. Whil~ printing
a design in this gener~l manner has certain deæirable
features, .it nev rtheless suf:Eers :Erom certain acute dis
advantages which t].le present invention is designed to
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overcom~. In the known process, t:he use of the recluired
paint solvents is objectionable not only because undesirable
working conditions are created but also because of the
hazards and costs associated with supplylng the solvents.
The drying -~ime of the we~ paint demands the use of valuable
space and expensive facillties to assure proper drying o
the pa.intD ~oreover, usually a suppl~ of natural gas or
bot~led gas is used to enhance the drying process through
burners; thus the prscess demands the continued avaîlability
of gas for heating purposes~
This type of printLng is useful for applying
decorations, the name of packaged products and even more
exten~ive information onto unma:rked containers3 but the
printing process requires a periorl ic replacement o the
etched plate~ usually on a daily basis when date coding is
printed along with other indicia which is etched into the
surface of the plateO Etched plates used to print designs
along with an ever~changing cla~e or code inormation must
be discarded even though the plate is undamaged because of
20 the need to update the printing of the proper date or cocle
information. This is an important factc)r to the printing
cost:5 .
The present invention oers advancements in the
art for printing a desired pattern upon an article o any
one o diverse forms and materials~ For example~ it is
currently a practice to us~ a printed design on the safe~y
glass o a windshield and/or backlight for an automobile~
One such printed design extends about one or more marglnal
edges oE the safety glass ~o form a shield or barrier
to prevent deterioration o:f adhesives or cther
ma~erials by ultrav1olet radiation~ Suoh a barxier
is also use~ or aes~hetic purpt~es. Films ~:E o~hPr
material are used on safety glass to form a heater
grid to prevent and/or remove an accumulation of fog
and/or lce9 Because o:f ~he size o:E the design which
must be printed upon the face of a glass sheet used
to :Eorm the windshield andfor backlight ~or an automo-
10 bile or other vehicle, printin~s by gravure was hPreto-
foxe not believed possible. A siïk screen :as used in
t~e present practice foY printirlg upon ~he fac:e of such
a g1 ass shee~ . Damage and ~ven destru ~ion of the screen
requently occllr because a sharp edge of the glass sheet
contacks and severs the screen when it is moved into ~he
proper posltion for print ing .
It is an object of the present invention to
provide an improved prin~ing method and appara~us ~o
transfer palnt with a dîstensible transfer memb~r from a
20 pa:inl:-laden image or design onto the surface o:f an article
to harden thereoII withs~ut heating the pa:in~ he article5
It is a further o~ect of the present :LIlveIIt:Lon
to provide a method and apparatus :Eor printlng with
thermoplast::Lc paint ~erein a ~i:Lk screen or an e~ched
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sur:ace of a member ~orms a pain~bearing pa~tern that
may be additiorlally defined by an insert by transfer
of ~he pairlt wi~h a dis~ensible kransfer pad on~o the
surface of an arl:icle ~o harden ~hereon prac~ical.ly
inst ant ly by ¢ ool ing .
A s~ill fur~her objec~ o ~he present inven~iorl
is to provide a me~hod and appaxa~us to hea~ ~hermoplastic
paint for dispersion o~ ~he paint ~o fOrM a pain~: l~len
image and transer of t:he lîquef ied paint at a.n elevated
10 temperature from the image onto the surface o~ an articleg
More speci:Eically, the pxesent invention pro-
vides a method and apparatus -or printirlg with ~hermo-
plastic pai~t wher~in ~he me~hod includes t~e s~eps of
supporting liquefied thermoplastic paint within a desired
pattern, adhering the liquefied th rmoplastic paint in
the patt rn to ~he heated surface of a distensible
transfer member by contact therewith under su:Eficien~
force causirlg elastic deformation to the heated surface
of the membes, thereaf~er moving the heated surace of the
20 distensible ~ransfer member wi~h the liquefied ~hermo
plastic paint adhered theraon to a distally~s paced, pa lnt -
discharging position, and pressirlg the heated s~rfaoe o:E the
dîstensible trans:Ee~ member with the liq~lefi.ed thermoplastlc
paint there~n agairlst a suxface of the article to
trarlsfer the liquefied ther~oplastic paint by solidi-
fica~iorl upon a sur:face of ~he article.
The inven~io~ provides various embodiments
of appara~us which are preferred to caicry ou~ ~he
aoresaid rrethod. The c~arrier used in the method
and apparatu~ is a debossPd plate, a debossed roller
or a silk-screen as~embly which may include a detachabl e
inser~ deinillg addi~ional indicia for printing upon
lû the article.. Such carriers are hea~ed, e.g., within
the range of 150F to 300F, by electrical re~is~ive
means or by in:Erared radiationO The distensible trans-
iEer member is a spherically-shaped sili~one rubber pad~
or a transfer roller with an annularly shapad silicone
sleeve thereonO The th~rmoplastlc paint is usecl in
the method and/or apparatus, when desired, as a
carrler fsr ceramic frit or firlely-d:Lvlded snetal
particles, whereby upon post-print:ulg operatiolls,
su~h as ~iring in a ~urnace, the paint is vaporiz~d
2û while ~he ri~ or pax~icles of meta:L are used ~o pro-
duce a ~ lm on th~ article.
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Th~ se :Eeat ure s and adv ant age s o~ t he
present invention as well as others w;ll bP more
fully understood when the fo:Llowing description
is reaa in light o:E ~he accompanying drawings~ wherein:
Figure 1 is a perspec~ive view 3f one
embodiment of the apparatus of the presen~ ins7en-
~lon which is useflll or carryirlg out ~he me~hod
thereof;
F:ig~ 2 is a sectional view taken along
10 llne II II of Fig. l;
Fig. 3 is a sectiorlal vlew taken alon~s
line III- III o:E Fig . 1;
Fig. 4 is an elevational view of apparatus
:Eor moving the 'cransfer pad b~ween pain~-receiving
and paint-d;scharging positions;
Fig, 5 is an elevational view of a second
embodiment of the apparatus of the present inven-
tion which is also llseful to carry oll~ the method
thereof,
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Fig. 6 is a sectional view taken aloIlg line
VI-VI of Fig. 5; and
Fig. 7 is a perspec~ive viPw o:f a further embodi-
ment of the apparatlls of the presen~ inventiorl which is
useful for carrying out the method ~hereof~
Referring to Figs. 1~3, there is illustrated a
carrier in the form of a debossed plate 10 located upon a
suitable support 11. The upper exposed face surface of the
plate includes an ~ched des.ign of an imag~ which, for the
purpose of illustration only~ forms the words i'YOUR DAIRY".
The etched image represents the desired pattern to be print-
ed. According to the preferred aspect of the present Lnven-
tion, th plate Eurther Lncludes a recPss 14 in clo~e proxi-
mity to the etched image. For the purpose of illustration
only7 the recess 14 is loca~ed between the words "YOUR" and
'1DAIRY" . When the recess 14 has a rectangular shape ~ an
.unsert element 15 has a corresponding rectangular shape to
tightly fit within the recess so that the top surface of the
insert is flush with the top surface of the plate. The
exposed face surface of the insert includes an e~ched pattern
of indicia, such as code dating~
The insert is held within ~he recess 14 by asten-
ers 16 which extend thro~1gh openings in the bottom o:E the
plate into threaded engagement with tapped holes in the
insert . While a rectangularly- shaped insert 15 has been
selected or the purpose of illustrating the present .inven-
tion, it will be unders~ood by those skilled in the art ~ha5c
any desired shape of insert may be employed including circular,
_ 7 -
square or the like~ Secured to the plate lO about its
outer peripher~l edges are upstanding side walls 18. The
side walls 18 retaLn a supply of ~hermoplastic pain~ on ~he
surface of the plate lO. A first supply reservoir of paint
is denoted by reference numeral 1~ along one side edge of
the plate and a second supply reservoir o:E paint i9 denoted
by reference numeral 20 along the opposite side edge o~ ~he
plate. According to o~e aspect of the present ~nvention~
the paint within these reservoirs is ~hermopl~stic hav~ng a
1~ liquidus temperature of about 200F but typically in the
range of b~ween 150F and 300Fa The composition of one
suitable form of thermoplastic pain~ is disclosed in U.~.
Patent No. 3,399,165.
Electrical h~atLng elemPnts 22 extend into bored
holes in the plate. The heat~lg elements are connect d by
a line coupled th~ough a rheostat 25 to a power supply 24.
The rheostat is used to vary the current delivered to the
heating elements and thereby control the heating of khe plate
10 to a suf:Eicient temperature :Eor conductive:Ly heating the
paint within the reservoirs 19 and 20 to a desired te~npera-
ture such as Lndicated above. Photosensitive paint is
utilized in reservoirs 19 and 20 according to a urther
aspect of the present inventionO Such a paint dries withouk
solvents by cur~g to a hard film when ~posed to ultra~
violet radiatLon.
A frame 26 is carried by two opposed side walls
18. The frame supports a squeegee 28 and a doc~or blade 2~
in a spaced apart and parallel relation so that each extends
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downwardly toward the face surface of ~he pla~e. The frarne
26 is moved ei~her manually or by suitabLe power means
across t~e face of the pla~e so that a supply of paint is
carried from a reservoir by squee~ee 28. The frame is then
rotated sli~htly about an axis extendin~ along its extended
length so that do~tor blade 29 engages the surface of the
plate to strip all ~he paint from ~he xurface of the plate
while providing a paint-ladeII etched designO
A spherically-shaped distensible transfer pad 30
is preferably made from so~t silicone rubber and forms an
elastomer transer member. The pad is supported by a earrier
plate 31. When prLnting with thermoplastic paint~ the pad is
heated to a temperature within the range above-indicated by
conductive heat transer from heating elements 32 that ex~end
into bored openings in the plate 310 The heating elements 32
are coupled to a controlled power supply Ln the same manner as
described in regard to heating elements 22, The distensible
transfer pad 30 is moved along a vertical path of travel into
contact with the surface of plate 10 wherein the distensible
transfer pad 30 is compressed into a somewha~ 1a~ened
condition from the spherical shape shown in Fig~ l~ Ac, this
occurs 7 some of the heated thermoplastic pain~ or photo-
sensitive paint contained within the etched designs of plate
10 and insert 15 adheres to the soft silicone rubber material
of the transfer pad in the same pattern as defined by the
etched design. When paint is carried on the soft silicone
rubber material of the transfer pad 7 the paint is ~aintained
in a fluid state because the transfer pad is heated. Ater
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~he transfer pad is lifted out o contact with the plate
10~ it is movPd to a dis~ally spaced locakion where it is
brought into contact with the surface o~ an article ~or
deposi~ing the paint carried on the surface cf the trans-
fer pad, Because the sur:face of the article is at ambient
temperature, h~ated thermoplastic pa.int solidifies on the
surface of the article almost instantly. The rapid freeziIIg
of the paint thus releases it from the transfer pa.d. When
photosensitive paint is employedg the paint is dried by
irradiation with ultraviolet energy~ A mercury arc vapor
tu~e 33 is l.ocated wi~hin an adjustably-positioned housLng
34 that includes a movable arcuate reflector 34A. The ultra-
violet radiation cures the paint very quickly wh~reby the
paint is hardened to a dry state.
The movem~nts of ~he transfer pad as just
described may be effected by hand-operation or preferably
through the agency of a device shown in Fig, 4. Thls devlce
essentially includes a vertical arm 35 secured to the car-
rier plate 31. Parallel arms 36 and 37 a.re secured for
pivotal movement to the arm 35 at spaced-apart locations. At
simi3.arly-shaped locations, the arms 36 and 37 are secured
by sha~ts 38 to a pivot ~haft 39~ The pi~ot shaft 39 is,
in turn, supported in a housi.ng 40 ~hat includes a bracke~
41 projecting in a generally parallel directi~n w:ith arm 37O
The bracket includes arms 42 whlch~ in Lurn, rotatably sup~
port a cam 43 such t:hat the surEace of the Ca~D. engages a
portion of arm 37. The arm 37 is ~naintained in c~ntac~ wi~h
cam 43 by a spring 44 which interconrlects arm 37 and bracke~
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41. A motor, not shown, is used to rotate cam ~3 and thus
effect a ver~ical reciprocating motion ~:o ~he transfer pad
by virtue o:E ~he parallel arms 36 cmd 37 be i.ng pivotally
connec~ed to arm 35 and pivot sha~t 39~ These members form
a parallelogram~ The ~ransfer pad is moved from a position
overly~ng the plate 10 to a position where it overlies the
surace of the ar~icle ~o receive ~he thermoplastic paint
carried by the transfer pad. For this purpose; a cam 45
driven by a motor~ not shown, contacts the vertical surface
o~ arm 37 so that upo~ ro~a~ion of cam 45, the arm is ro~a-
ted about pivot shaEt 39. It will be understood by ~hose
skillPd Ln khe art that linear actuators, such as piston and
cylinder assemblies, may be used to move the support struc-
ture for the transfer pad in a manner similar to that just
described through the use of cams 43 and 45. It will also
be understood by those skilled Ln the art that sources of
infrared energy such as radiated by an incandescent lamp may
be dirPcted toward the surface of plate 10 and another source
directed toward the surface of transfer pad 30 Eor heating
the ~hermoplastic paint in place of heating elements 22 and
32. Printing upon any one of diverse surface c~ltours of
an article will now be readily apparent to those skilled in
the art.
Figs. 5 and 6 illustrate a second embodirnent of
the apparatus which is also useful to carry out the method
according to the present inventio~. The apparatus utilizes
rokary motion to transport heated thermoplastic paLnt or
photosensitive paint :Erom a debossed carrier to c~m elaskomer
3~
member and thence onto the surface of an article. A housing
50 Eorms a gearcase wherein arbor shafts 51 and 52 are
supported in a generally parallel relatîon by spaced-apart
bearing~ 53. Gears 5~ and 55 are carried on the arbor
shafts Sl ancl 52~ respectively, which are spaced apart for
meshing engagement by the gears. A motor 56 is coupled to
an extension or arbor 51 at one side of gearcase 50. A~
the opposite side of the gearcase 50,, arbor sha:~t Sl is
coupled to a roller assembly 57 which includes an outer
sleeve 58 carried on a support flange 59 that is~ in turn~
secured to arbor shaft 51. The arbor shaft 52 is coupled to
an elastomer roller assembly 60 which includes a sleeve 61
made of silîcone elastomer material carried orl a support
flange 62 secured to th~ arbor shaft 52. When printing with
thermoplastic paiht~ each arbor shaft 51 and 52 has a
~entral bore to pass insulated wires from separate collector
rings 63 located within the gearcase. Brushes 64 deliver
electrical current ~rom a controlled power supply 65 which
includes Q rheostat in a manner similar to that described
~0 previously in regard to Fig. 1. The .insulated wires extend
from the ends of the arbors on which roller assemblies 57 c~nd
60 are supported. A junction box clistributes electrical power
from the power supply 65 to radially, spaced-apart heating
elements 66 embedded in each of the support 1anges 59 and
62. The heating elements 66 provide a sourc~ of hea~ t:o
main~ain thermoplastic paint at a desirecl tempera~ure within
the range indicated hereto:Eore~ The thermoplastic paint is
con~a:ined within a reservoir 67 supported in a manner so tha~
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the peripheral surface of roller assembly 57 dips into ther~servoir below the surf~ce of the paint in t'ne reservoirO
As shown in Fig. 6, sleeve 58 is debossed by pro-
viding an etched design defining the wo~ds "YOUR DAI~Y~.
~n Lnsert elPment 68 is secured wi~hin a recess adjacent
the debossed area. The insert elemen~ is etched or other~
wise provided with a relief design defining-desired indicia
to be printed along with the debossed design in the surface
of sleeve 58. The ins~r~ element is readily replaceable by
screw-type fasteners so that dif:Eerent insert elements hav-
ing desired indicia may be used from time-to-time. As the
etched surface of the sleeve 58 as well as the etch~d sur-
-face of insert element 68 pass into the reservoir, thermo-
plastic paint adheres to the face surfaces of these members.
The roller assembly 57 is rotated in a clockwise direction,
as one views Fig. 5, beyond the proJected edge of a doctor
blade 70 which strips the thermopLastic pain~ from the face
~urfaee of the member 58 and insert 68 to provide paint-laden
relief image~. The doctor blade is supported in an adjust-
able manner by a mounting block 71 ~hat is, in turn, receivedwithin a carrier 7~ wherein it is releasably secured by a
threaded sllaft 73. Shims 74 are used to position the doctor
blade with respect to the roller assembly 57~ The paînt-
laden relief images on the roller pass into contact with the
elastomer sleeve 61 whereupon sorne of the paint rom the
relief images is carried by the sleeve in a dlrection which
is counterclockwise to the rotation of roller assembly 57O
At some point spaced from tlle contact between th~ roller
asse~blies 57 and S0, the paint carried by the elastomer
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sleeve is brought into contact wlth the article ~o be print-
ed. l'ypically, articles printed by using the apparatus
show~l ln Figs. 5 and 6 include bottle caps and similar clo~
sures. A conveyor 75 carries the articLe for printing hy
contact with the elastomer sleeve 61. Prin~ing of such
articles is carried out at a relatively high rateO
When printing with photosensi~ive paint9 heating
of the roller assernhlies 57 and 60 is eliminated. The paint
is dried by curing when exposed to ultraviolet radiation in
the same manner as described hereinbefore in regard to Figs,
1-3. Typically, for exampleg the photosensitlve paint cures
withirl microseconds depending, of course, on the thickness
of ~h paint which is deposited on the article. Presen~ly,
there are two known sources of supply o the photosensitive
paint5 one called Linde Photo Cure from Union Carbide and
one called Photo 5et from K.C. Coatings of Kansas City.
The embodimen~ of the invention shown in Fig~ 7
is particularly adapted for printing a desired pattexn upon
a rela~ively large surface of an ar~icle such as safety
glass to form a windshield or a backlight of an automobile.
By way of example, the method and apparatus of ~he present
invention are useful to form a film on th~ glass extending
along the marginal edge of one g several or even all of the
sides of ~he safety glass. Such a band is currently pro~
duced on such articles by other methods and the band is
typically about 1-1/2 inches in width to Eorm an impervious
film to light for a2sthetic purposes and irnpervious to
ultraviolet radiation for preventing adverse deteriorating
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effects to the adhesive and other materials used to affix
the safety glass to the frame of the vehicle. Another
pattern that is curren~ly produced on safety glass for
au~omobiles takes ~he form of a grid use~ ~or resistive
heating of the safety glass to prevent or rernove Eo~ or
ice accumulations on the glass. When prln~ing is carried
out to foxm a pat~ern of a marginal light and ultraviole~
radiation impervious coating, thermoplastic paint is admixed
with an effective amount of ceramic frit selected according
to ~he desired color and other properties. The cerami.c frit
is inely divided to such an extent to pass through a 350 or
400 mesh screen. The particles o~ ceramic frit should be
sufficiently small to remain in s~lspension in the ll~uid
thermoplas~ic paint~ The thermoplastic pain~ in thi~ în-
stance serves as a carrier for the ceramic frit to produce
dry printing of the desired pattern on an article for immed
iate handling because the admixture of thermoplastic paint
and ceramic frit solidifies almost instantaneously upon the
safety glass~ When it is d~sired to print a pattern forming
a heating grid on the safe~y glass~ a suspension is prepared
by admixing the thermoplastic paint with finely divlded
metal particles such as silver in effective proportionsO
A~er printing o~ the desired pattern, the glass is heated
in a fuxnace to vaporize the ceramic paint and fuse the
metal particles to the glass. A continuous metal film
correspondLng to ~he print~d grid pa~ern i5 then allowed
to cool.
In Fig. 7, the apparatus of the present in~7ention
shown therein includes a support 80 which may ~ake the form of
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a conveyor to move shee~s of glass or safety glass into a
regis~ered posi~ion for printing upon the exposed face
surface thereof. Usually, printing will be carried out on
a glass sheet rather than a safety~glass assembly because
the subsequent firlng opera~ion is detrimental to the
plastic sheet used in safety glass, AE~er firing, a
safety-glass assembly will be made up according to the
usual practice. A sheet of safe~y glass is identified in
Fig. 7 by reference numeral 810 The safety glass includes
the usual lamLnated cons~ruction of glass sheets with a
sandwiched layer of plastic material therebetween. The ex-
posed face surface of the glass havLng undergone the prin~ing
process ~f ~he present invention con~ains a printed layer of
thermoplastic paint admix~d with ceramic frit extending
abou~ the entire marginal edge of the glass sheet. The
printed f ilm o-E this material is identif ied by re~erence
numeral 82. The printing appara~us shown in Fig. 7 preferably
includes a silk-screen assembly 83. This assembly includes
a frame 84 having side walls defirling an opening in the frame
between which a stencil screen 85 extends for attachment and
support by an adhesive to the side walls of the frame. The
silk screen, or stencil screen as sometimes identified in the
art, bears outlines of the clesired design f~r printing by
processing through the use of well-kno~l techniques and the
use of an emul~ion or film to render the screen impervious
to the passage o~ paint mixture except throllgh areas defined
by the desired pattern. The areas of the screen which do
not eontain a paint~impervious film are used to conduct the
paint through the screen~ In this regarda thermoplastlc
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paint admixecl wi~h the selected finely~divided material ~orthe intended purpose i5 maintained in a liquefiecl state by
contact with the screen which is heated. Tabs 86 and 87
extend from the ends of the frame 8~ ~or support by up-
standing columns 89. T~e tabs 86 and 87 support or form
conductors that are, in turn~ connected to th~ ~erminals of
a con~rollPd power supply for resis~ive heating of the
screen. The ~hermoplastic paint mi~ture is placed within
the frame on the coa~ed screen where it is liquefi~d by
resistive heatLng ~hereof~ The li~uefied thermoplastic
paint is forced through the paint- pervious openings in the
screen by a squeegee 88. A frame9 not showng above the
silk screen is used to support the squeegee and pis~on and
cylinder assemblies move the squeegee across ~he face of the
screen under a controlled ccntact pressure. If desired, the
squeegee is moved across the face of the screen inside the
frame by the h~ld.
The support COlU~lS 89 are also used to pivo~ally
carry levers 90 each having a projectecl end to which there
is secured the rod end of a piston and cylinder assembly 91.
The levers 90 are mounted for pivotal movement by pins so
that the ends of the levers projecting toward each other are
moved ver~ically. These projected ends of the levers have
slotted openings that receive pins carried by support blocks
attached to a frame 92. The frame has a rectangular con
figuration with slotted openings along its longitudinal
sides that receive bearing chocks to sllde along the openings
while carrying khe j ournals of a roller 930 The roller has
a face eclual to or preferably greater than the width of ~he
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silk~screen assembly 83. The roller has a drilled body toreceive heaters that are connected to a power supply in the
same manner as previously descrlbed in regard to Figs. 5
and 6. A sleeve of distensible material~ preferalbly soft
silicon rubber, is adhered to the roller to form an elas-
tomer transfer member. The bearing chocks for ~he xsller
are joined together by a cross member g4 that is, in turn~
coupled to the rod end of a piStOIl and cylinder assem~ly
9S. This piston and cylinder assembly is operated to move
the bearing chocks and~ hence, also ~he roller supported
thereby, ~long the slotted opening in the frame. When the
frame is moved into its upper pOsitlO~ by operation of
piston and cylinder assemblies 91~ the distensible sleeve
is pressed agalnst the underface surface of the silk-screen
assembly. As the roller is traversed across the underface
surface of the screen, it rotates by frictional contact
therewith or by a motor 96 coupled by a suitable drive to
the roller. The heated thermoplastic paint admixed with the
Lnely-divided substance is forced through the pervious open
ing in the screen by the squeegee and adheres to the surface
of the roller. -rt is wlthin the scope of the present inven-
tion to move the squeegee across the screen prior to move~
ment of the roller; to move the squeegee and roller together
with the squeegee forming a tangent ~o the roller~ or move
the screen with t'ne squeegee tangent to the roller. More-
over, the apparatus already described and sho~ in Figs. 5
and 6 is readily useful for printing on a glass sheetO
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It is to be understood, of course~ that ~he
peripheral ace surface of the roller ls at least equal to
but pre-ferably grea~er than the face surface of the siLk
screen to ther~by insure that ~he r~ller rotates through
no more than 1 revolution while displaced across ~he face
of the silk screen. The roller 93 carries adhered thermo-
plastic pain~ on the surface of the elastomer sleeve after
movement out of contact with the silk screen. The frame ~2
is then lowered by actuation of piston and eylinder asem
blies 91 into con~act with a sheet of glass which was pre-
viously positioned beneath the frame. The frame is lowered
to such an extent that the distensible sleeve thereof is
brought Lnto contact with the glass sheet. As this occurs 9
the piston and cylinder assem~ly 95 and/or motor 96 is
again actuated to rotate the contacting surface of the roller
across the face oi the glass sheet. The liquefied thermo-
plastic pa m t adhered to the surface of the roller solidifles
upon contact with the surEace of the glass. The glass sheet
with the solidified thermoplastic paint mixture thereon is
then indexed ~rom its position below ~he roller and trans
ported to storage -facilities, if desired, where the printecl
sheets of glass can be immedia~ely stored without delay.
However, the printed glass sheets can he fed direc~ly into
a Eurnace for firing to vaporiæe the thermoplastic paLnt
and leave only the enameL frit on the surface of the glass
sheet where it ruses to form the desired coating~ Other
'creatmen~ and processing of the glass after fusing of the
admixed substance with the thermoplastic paint rnay be
carried ou~ in any desired manner for the intended purpose
of the artLcle.
_L9_
~ 3~
Although the invention has been shown in con-
nection with certain speci~ic embodiments, it will be
readily apparent to tho~e skilled Ln ~he art that various
changes in form and arrangement of parts may be made to
suit requirements without departung from the spiri~ and
scope of the inventiorl.
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