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(11) | EP 0 736 379 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Long table serigra phic printing machine with balanced propulsion and equidirectional compensated adjustable repeat |
| (57) Traveling along the printing table impelled by two gears , each one of them engaged
in one rack conveniently fixed in the corresponding side of said table. With the repeats digitaly adjustable to the mean lengths given by the racks teeth pitch. Dinamicaly rigidized by the shaft that desmodromicaly engages the two impelling gears between them and with the two side racks. With modularized plane rigid structure allowing easily building of different sizes both in width and maximum repeat length and giving a precise alignment after a round rail gide when in static position. With positionning equidirectionnality for each printig repeat. With the longitudinal synchronisation of the rack's pitch when they are fixed to the table's structure. Improving the printing precision, its productivity, its functionnal reliability and its dimensionnal and programatic adjustability. |
[0001] The printing of textiles and other substrates by the serigraphic process, using long tables as a fixed support of such a substrate and with a rail or guide generaly metalic for the correct positionning as well in alignement as in advance or repeat of the screen frames, is known from long ago, having attained great difussion at the mid of this century.
[0002] With this process,the die is pushed througth the mesh in the non varnished screen areas,by means of a moving blade or squeegee
[0003] In the following explanations, instead of repeating fabric or other substrate to be printed, we will use the word fabric,and instead of pattern or flat screen we will use the word screen.
[0004] The serigraphic manual printing still in use was followed by a variety of more or less automated carriages gliding along the table rails.usually refered to as printing carriages.
[0005] In this patent application,the mention of machine should be understood as refering to a printing carriage.
[0006] This kind of machinery appeared in the fifties under the form of manual carriages gliding on weels guided on the corresponding rail and with the rising and lowering of the screen and the the repeat indexing were obtained by manual levers and the squeegee was a single one,moved and raised by two handles -one in each operator's hand.
[0007] The most prominent manufacturers of this kind of machinery were Viero,Robustelli and Mecanotessile in Italy,Societe Alsacienne des Constructions Mecaniques de Mulhouse in France,Hobbo in Holand and Peter and Johannes Zimmer in Austria
[0008] In the sixties this applicant designed patented and manufactured,(Spanish patent 3741223 of 1969 extended before the following 12 months to Argentina, Austria, Brasil, France, Holand, Italy, Japan, Mexico, Portugal, Germany, United Kingdom and Switzerland) one printing carriage with all the described functions fully automated and faster by means of compressed air, with squeegee pressure and speed and span of each movement fully adjustable within broad limits.
[0009] Due to its simplicity and working fiability from the last sixties trhough the seventies this machine was the first in the sales ranking, with more than 1300 units supplied to more than 400 printing shops in more than 50 countries.
[0010] Perhaps we should make clear that we refer once more to the serigrafic printing over long table,that is to say, printing wet over dry where between one printing passage and the next, including the return, sufficient time has elapsed for, with the ambient conditions of heat and air movement, the previous printing die would be suficiently dry not to mix with the following color or to wed the screen sides when pressed by the squeegee.
[0011] These advantages are additionnal to the alternate repeat printing by which the od repeats are printed in one machine's passage and the even ones in the next, to avoid the screen sides pressing over the printed dies.
[0012] Moreover,by this wet over dry printing procedure,the number of screens (and of dies)to be printed is not limited by the size of the machine, giving thus a complete freedom of textile design.
[0013] The final gloss obtained with most dies used, is directly related to a minimum time to be dried, confirming thus the long table printing as the best quality one.
[0014] At the same time that automatic screen printing carriages were developping,companies like Fritz Buser in Switzerland, Zimmer in Austria and Mecanotessile and Reggiani in Italy , developped another systems of screen printing machinery of continuous printing process, where,adhering temporarily the fabric to be printed to an endless band and printing on it wed over wed consecutively with the desired screens (as many as the dies required by the printing design until the limit imposed by the size of the machine) and detaching the fabric once printed, obtaining great productivity with some limitations in quality,number of dies and difficulty of design.
[0015] Later on, Stork in Holand,developped with great success the circular or rotary screen printing machine , solving with it some of the screen pressing problems and improving thus the wed over wed printing quality and by avoiding the flat screen printing alternativity it improved the productivity, always, like in the flat bed machines, screen printing all the dies cosecutively without suficiently long intermediate drying.
[0016] More recently, M.S. and Viero in Italy, to avoid the problem of wed over wed printing and at the same time to reduce the surface ocupied by the printing tables and to improve the automation of the related process they have intended to introduce a new concept that they call "tavola rotante" or turning table where the long table is flexible like in a continuous process,but were tre printing process is made essentialy like on a fixed long table.
[0017] These diversity of solutions, until the profuse permanence of the entirely manual tables , where the screeen with its frame together with the die and squeegee is taken by hand and raised from one repeat to the next, shows the permanence of an important market in high quality serigraphic printing on long table by the wet over dry process.
[0018] On the long tables, there is always the problem of repeat that means to change the position along the table of a kind of metallic stops (called repeat stops) that should be loosed and with a special gauge be situated at a precise distance for the desired design and fastened again with great care to avoid any misplacement.
[0019] The repeat stops setting must be made by a well qualified worker and stops the table production for a half an hour, but the worst is the difficulty for further readjustments that could be shown necessary after the printing of the first repeats.
[0020] To solve this problem, in the early eighties we decided to design a selfrepeating printing carriage, that is to say, runnning along the table at identical distances and being able to modify at will the repeat with the needed precision.
[0021] The result has been a new series of machines in pneumatic (LXP), and in electronic self repeating version (LXE), (spanish patent 8700754/1 and italian 1219079) of which we have supplied more than 200 units with new experiences that has lead us to the following:
CONCLUSIONS:
[0022] Until now, in all the printing carriages, the longitudinal driving is engaged at only one side of the table and machine,usually the one from which the printer supervises the process.
[0023] In such a machine, which for productivity reasons is submited to fast alternative sequencial movements with strong impulses, the lateral unbalance during acceleration braking and blocking, submits the machine and table structures to great stresses.
[0024] Such stresses have imposed more rigid machine structures with the consequent increase in its weight, which impeaches the eficiency improvements inspite of the unavoidable reinforcement of the printing tables.
[0025] Moreover, each time a high rate of printing is intended, the said unbalance, producing elastic pivoting oscillations around the blocking point and submitting the guiding rail to bending, reduces the precision in longitudinal repeat and lateral centering.
[0026] The rail for guiding the machine along its table is nearly always a round shape precission finished steel bar accurately straight and bolted every 25 cm to an stronger profile fixed to the table.
[0027] The printing machine guiding weels for its traveling along that rail, have been always v channeled and for the diferential contact radius in that channel, once the weels and rail wearing has increased the contact surface, the friction between them is also increased, expending more energy for traveling and reducing the printing precision.
[0028] Moreover, the great variety of printig shops that use this kind of machines, from the small artisan printing short runs on commission in only one table,to the great vertical process textile complex with dozens of very long electricaly heated tables, has conviced us of the need for a basicaly simple, reliable and low cost machine , allowing the incorporation of all the controls and accessories asked for in the most sofisticated shops.
PROPOSED SOLUTIONS:
[0029] Te invention is referring to a machine for the serigrafic printing of fabrics of the type commonly named printing carriage,that runs along a table -1- over which the piece of fabric -2- to be printed is fixed and which machine is guided by means of weels -3- who are running over a roud rail -4- bolted and correctly aligned on one side of said table,they hold and guide longitudinaly one side of said machine, while the other side of the same is hold on weels -5- who run over a flat rail -6- horizontal and correctly leveled with the rail -4- in the other side of table -1-.
[0030] To avoid the wear of the round rail -4- the guiding weels -3- are mounted by pairs with their axis crossed so the rail -4- wear is changed to a surface cold hardenning lamination. of same rail.
[0031] When necessary, the pairs of weels would be mounted in assemblies of two or four pairs with the new designed supports -109- and -110 - allowing two degrees of elastic fredom to each two pairs of weels with the consequent advantages of distributing the weigt of the machine fairly well between two or four sets of less charged weels ,reducing rail lamination and vibration of machine when running over the joints of the rails.
[0032] These new designed supports take advantage of the bending and torsional flexibility of a thin plate to provide for a good sitting on the round rail of the two pairs of weels, taking advantage of the same thin plate in the sense of its highest moment of inertia to secure the necessary vertical and transversal to de rail guiding rigidity.
[0033] When the use of double pairs of sets is the case,the two thin plates are bolted to a rigid bridge that is solidary of a central thin plate -111- that holds the complete assembly.
[0034] The machine is driven and eventually blocked by both of its sides in a symetric and balanced way towards its gravity centre and the table central axis.
[0035] The machine weigt reduction that this balancing allows for, gives the possibility to modularize its structural parts, reducing manufacturing and assembly time and cost and making easier to modify a suplied machine when required.
[0036] Once the machine is ready to travel along the table -1-, suited means have been provided in said machine to make it go ahead by precise longitudinal lengths or repeats previosly stablished, bearing in mind that, after each advance, the serigraphic screen -7- held on by the machine,will sit down on the table -1- or remain very close to it, to allow that the squeegee -8- with its stroke, makes a certain quantity of die to go trough the screen's mesh left open by the photogravure treatment of the textile design..
[0037] The screen -7- descending, squeegee stroke, screen rising and table repeating, are sequential, succesive, fast and smooth.
[0038] For this purpose, the machine is light and rigid and the characteristics of its squeegeing and repeating motors are the suitable for said duties.
[0039] Electric energy is used for the machine longitudinal advance and return, the squeegee strokes and the control of stroke length and all the speeds and accelerations.
[0040] Electric energy is also used to feed the electronic and informatic hardware the air cooling of the repeat motor -9-, its controls -10- and the squeege motor -12- controls -11-.and for the feeding of auxiliary devices as table cleaning aspirators or fabric extenders.
[0041] The electric supply could be by the known system of brush friction trolleys or by a flexible flat set of cables -14- of the commonly used for traveling devices.
[0042] The cables and trolleys feeding the electric motors trough their controls,are feeded at their time trough a transformer to filter the back electromagnetic interferences.
[0043] On the contrary, the cables and trolleys feeding the electronic equipment, are feeded trough a current tension estabilizer.
[0044] The aforementionned transformer and estabilizer are staticaly fitted under the printing table not to increase the mass of the fast accelerating printing machine.
[0045] Compressed air is used to energyze the rising and lowering of screen -7- and its clamping,for the rising and lowering of the squeegees and the setting of its evenly adjustable pressure on the screen, and for the clamping to the table flat rails of the machine frame holding the screen,in order to impede any transversal displacement of it in the weft sense.
[0046] The machine is driven along the table by means of two gear weels -18- engaged with two racks -19- fixed respectively at each side of the printing table -1-.
[0047] To protect them from infalling dirtiness, the said racks -19- are fixed in inverted position in the downside of a calibrated flat handrail bolted to the table metalic structure and to the guiding rail to obtain the desired vertical and transverse rigidity as well as the precise even distance between the teeth -20- of the rack -19-and the closest rail -4- or -6- guiding surfaces.
[0048] The gear weels -18- engaged with the racks may be substitued by geared belts -21- of suitable no clearance profile driven by a combination of two pulleys -22-engaging the belt -21- to the rack and a toothed weel -23- tangentialy pretensionning said belt -21- and transmitting the driving force to move the machine.
[0049] To provide for the best matching between belt and rack, several guiding small pulleys may be mounted.
[0050] The two driving weels -18- engaged to the racks -19- or in their place, the toothed belts -21- that accomplish the same duty, are solidary between them in their turning movement by means of a transversal shaft -25- of a suitable torsional rigidity to ensure the rigth synchronisation of traveling of both sides of the machine.
[0051] The transversal shaft -25- is driven trough a gear pulley -26- equidistant of the shaft ends to secure that any torsional deflection will be transmitted symmetricaly, not giving misalignements that could revert in lack of centering precission or matching with the neighbour prints.
[0052] The electrical motor -9- that, by means of a no clearance gear belt -27- drives said centered geared pulley has, coupled to its shaft, an encoder or resolver -28- of enough resolution to reproduce any desired repeat length along the table -1-.
[0053] The encoder or resolver -28- may if convenient,be coupled to one or both ends of the transversal shaft -25- or even at the driving gears shafts -29-.
[0054] Each one of said driving gear shafts -18- is mounted at the end of a shaft -29- which at the other end wears another gear weel -30- that, by means of a no-clearance toothed belt -31- ,is driven by the toothed pulley -32- mounted at each end of the transversal shaft -25-.
[0055] Both transversal shaft -25- ends and parts -32-, -30-, -31-, -29-, -18- and its support -33- and bearings -34-, -35-, and -36-, are parts of two driving assemblies that can move guided after a vertical axis at right angles with the table's plane in order not to introduce any lengthwise displacement related to the unavoidable small distance allowances between the racks -19- and related rails -4- and -6-.
[0056] This vertical stroke,by means of the pulling or pushing of a spring -37- or the equivalent compressed air cylinder, is needed to avoid any clearance between gear weel -18- or toothed belt -21- and rack -19-, being also necessary to disengage these two elements in in its descending stroke when the machine needs to be table-exchanged.
[0057] The small vertical stroke of both driving assemblies are possible without the need to move the central part of the transversal shaft -25-, its pulley, -26- and the motor -9- by the said shaft's -25- flexibility due to its length in machines for usual table widths.
[0058] The transversal shaft being made in two halves with flexible joints , no rising mechanism is necessary for its central pulley, even for very narrow machines.
[0059] The main frame of the machine in weft stroke version consist basicaly (without limiting purposes) of six rectangular tube steel profiles of constant section -38- to -43- with the necessary holes and indentures to be bolted to the modules of: union -51-, support -52-, squeegee guiding -53-, rail guiding -54- and -55-, rack engagement driving -33-, careenage -56- to -62-, control -63-, hinge -53-, interlocking -113- and flat rail clamping -114-, standard for a wide series of machines.
[0060] Two longitudinal main profiles -38- and -39- wear the weels supporting the weigth an guiding the machine -54- and -35- as well as the rack engagement driving -33-.
[0061] The operator's side longitudinal main profile -38- also incorporates the squeegeing electric motor -72- with an encoder -73- at the end of its shaft that sets the squeegee stroke and its centering, the driving reductor and the shaft that hold the end small pulleys to drive by means of two toothed belts , the squeegee holder boggies.
[0062] Te aforementionned profile incorporates the hinges and eventualy the rising air cylinders for the frame holding the screen.
[0063] The contrary side longitudinal main profile -39- incorporates the compressed air cylinder and its device to raise and descent the screen holding frame , the interlocking devices to secure the precise down screen position and the flat rail clampings to secure that no relative movement between screen and table is allowed when the squeegees and their related holders and driving boogies are accelerated or decelerated back and forth in their transverse movement.
[0064] The other four main profiles unite transversaly and rigidly with the longitudinal ones, two of them to hold the squeegee gliding guides and the other two to hold the travelling motor, the transversal shaft and all the electronic and computer hardware as well as the pneumatic logic elements, the control board, the upper an lower careenage covers and the air cooling fan, as well as the fabric on the table lint vacuum cleaner if convenient.
[0065] The mentionned main steel profiles form a very rigid frame, united in its corners by specially rigid union modules.
[0066] This rigidity is very important to compensate for the necessary torsionnal flexibility given to the transverse shaft and related drivings, to keep the armonic torsionnal elastic resonance of its two branches,(from the electric motor's shaft to the two rack's teeth) into a frequence well below the 50 or 60 hertz of the alternating electric current supplied by the mains.
[0067] Another four profiles, -43- to -46 this time aluminum extruded ones,form the single or double tilting frame that holds by their ends, the profiles -48- and -49- that gliding along the profiles -45- and 46- give the suitable position to the centering devices and clamps they incorporate to hold the flat screen and rise it by only one side or both sides depending on the table's width.
[0068] The use of extruded and anodized aluminum profiles, is to easily adjust to the screen size the profiles -48- and -49- and centering devices with bolts, heads and nuts, into their grooves and to make them as light as possible and rust protected .
[0069] The last profile -47- holds on the squeegee holder -75- with its clamps -76- and raise stroke guides , as well the air cylinders -77- that distribute the squeegee pressure evently over the screen.
[0070] The required precission on the flat screen -7- centering ,for the necessary coincidence between reference points in successive screens, as well as to match the successive printings of the same screen along the fabric on the table , has made us to incorporate into the computer program of the machine the condition that the flat screen -7- cannot be laid down unless a forward machine displacement , be it of repeat or of a few centimetres if the machine was coming back , is run.
[0071] Said movement will be always in the advance sense to compensate for any elasticity, friction or clearance that could introduce the slightest lack of precission in the repetitive flat screen -7- centering.
[0072] The racks incorporated to the tables could be of any type and material provided the precission and regularity of its pitch and capacity of charge would be adequate.
[0073] Good table racks are the thoothed belts of polyurethane and other plastics be reversible or not , molded over a metalic reinforcement of any kind that currently is made by a plurality of steel tressed or twisted cables -78-.
[0074] To obtain with precission the same pitch in synchronisation or metric coincidence of the two racks -19- mounted in the same table -1-,and on the neighbouring tables intending to print with the transferred same machine and screen we will operate as follows:
[0075] With the racks clamped in a table's end matching with the gears -18- solidary through the transversal shaft -25- such racks will be suspended an guided by a plurality of small pulleys guaranteing that no important friction is allowed on the rack along the table.
[0076] Then, by the action of a threaded adjustable tensor clamping the rack at the contrary table end, this rack must be stressed until the measurements taken with a long high precission teeth gauge shows that the recommended pitch is atteint.
[0077] Once each rack -19- is correctly stressed , it must be secured at regular short distances by means of shoes -79- clamping two lateral wings -80- by means of bolts -81- to the handrail -82- solidary of the rails -4- and -6-.and the steel structure of the printing table , not allowing that any section of rack -19- could remain free in sufficient length for,by its longitudinal elasticity could give sizable screen misalignments or excentricities.
[0078] If the rack is enougth wider than the driving gear teeth or the toothed belt matching it, the lateral wings are not needed provided that the clamping shoes -115- are indented with the racks pitch and clamping the rack with several nails penetrating into the racks plastic amid the teeth and between the first and second cable at each side of the rack
[0079] This shoes will have elongated bolting holes to secure the threaded holes coincidence by jumping the clamp from one tooth to the next one , when necessary.
[0080] Contrary to the other printng carriages ever made , we provided it with integrate standard electronic hardware consisting of a central unit -66- of a personal computer popular in the market , to which we have incorporated two electronic circuit cards to suit it to the specific functions of printing process.
[0081] Said computer has a drive to introduce through a diskette the desired printing program as well as to register in the same the data to be memorized concerning the operations for a given printing design.
[0082] The data may concern the length of repeat and squeegee strokes , the speeds of repeat and sqeegee , number of squeegee strokes per printing , if alternative or continuous repeats , and even complex processes as printing with squeegee return over raised screen ,or alternative repeat with partial return every few strokes to prevent screen drying when using a very fine screen mesh.
[0083] The registered data allows to reproduce with fidelity the same printing conditions each time a similar order is repeated.
[0084] The printing tables are usually covered with two layers of a good quality wool felt (between which an electrical heating blanket is eventualy placed) all to be covered with a thick , longitudinaly and transversaly strongly stressed rubbered or plastified canvass.
[0085] This covering provides for a surface that is soft in vertical sense and very rigid in all the plane senses.
[0086] As the kind of this covering deeply changes depending on the printing duty the table is intended for,in the drawings that , after this application claims , are incorporated to this document,the machine is designed over a modular metalic table with wooden aglomerate top of the standard type we supply , without any covering on it.
[0087] In weft stroke squeegee machines,to secure the correct screen -7- undeflected rising and its subsequent precisely coincident lowering , we provided a rigid and articulated paralelogram device -83- with a rigid triangle -84- adjustable in length , linked to a rotule -85- to compensate the flexions.
[0088] Said articulate paralelogramme -83- is solidly bolted to a torsion bar -86- solidary with a lever -87- linked to an adjustable connecting rod -88-.
[0089] The articulate paralelogram -83- and the end of the torsion bar -86- are articulated in the supports -89- , -90- and -91- bolted to support weels profile -39- and the rotule shaft -85- and the connecting rod -88- are articulated to supports -92- and -93- bolted to the tilting profile -44- of said machine.
[0090] The warp squeegee stroke machine reaches the same results by means of the torsion bar -94- and the bracketed levers -95- and bracketed connecting rods -96-
[0091] To compensate for the flexibility of the operators oposed bars -39- and -44- in big weft stroke machines , one or two compressed driven clamps may be incorporated to the main frame to clamp the flat handrail an secure that no transverse screen sliding due to the squeegees assembly inertia is allowed.
[0092] The tilting frame holding and clamping the screen ,being thinner than the main frame and made of aluminum ,is much more elastic , so a guided anchor centering device -113- that may be incorporated in one,two or more units , ensures that at its lower position , the tilting frame is solidary to the main frame not only in the repeat , but also in the squeegeeing direction.
1. A machine for printing fabrics and other substates by the wed over dry flat serigraphic
process, traveling along a printing table -1- which machine is driven by two gears
-18- or, eventualy ,two assemblies constituted each one by one gear -23- engaged without
clearance in a toothed belt -21-that at its time is kept under tension by two pulleys
-22- and pushed by them and a plurality of small rollers to engage without clearance
with each one of two high precision made silent steel cable reinforced polyurethane
racks -19-, each rack being solidary with said table -1- at each side of it.
2. A machine under the claim 1 in which each gear -18-, or the assemblies of a gear ,
two pulleys -22- and geared belt -21- together with the end bearings -34- and the
end geared pulley -32- of the transversal shaft -25- form together two propulsion
assemblies -33- each one of them mounted into two duly adjusted sliding guides -64-
or flexible paralelograms -116- that allow said gears -18- or propulsion assemblies
-33- a pneumaticaly driven vertical displacement perpendicular to the table -1- plane
, such displacement , when ascending , engage without clearance the gear -18- or geared
belt -21- with the rack -19- and when being descendant disengage the assemblies -33-
to allow the machine to be transferred from one printing table -1- to another.
3. A machine under the claims 1 and 2 in which the longitudinal propulsion geared wheels
-18- are solidly engaged between them by means of a transversal divided and universal
flexible joint connected shaft -25-.that provides an even distribution of the pulling
and pushing of gears over the two racks and at the same time , when indexing the nearly
stopped machine ,take the mean pitch of the two racks teeth as reference for precise
indexing.
4. A machine under the claims 1 to 3 in which the engagement between the said transversal
divided shaft -25-, the geared weels -18- engaging with the racks -19- and the electric
motor -9- driving the same shaft by the pulley -26- and the geared belt -27- , is
done by means of elements without any play or clearance , as geared belts or precision
gears where the pressure angles of their teeth flanks are suficient to allow for an
adequate radial precharge.
5. A machine under the claims 1 to 4 in which the electric motor -9- driving the transversal
shaft -25- may be accelerated and decelerated after a squared sinus function and its
turns can be measured by an electrical encoder or resolver-28- directly coupled to
the motor shaft , said encoder or resolver , by means of the program introduced through
the control desk keyboard ,sets through the electronic control of said electric motor
, the precise repeat length and all the necessary adjustments , allowing within certain
limits , to chose the most suitable acceleration rates and translation speeds..
6. A machine under the claims 1 to 5 which structure is made by constant section beams
suited to be bolted to adequate modules of union -51- , of support -52- ,of hinge
-53- ,of wheeling -54- ,of guiding -33- , of careening -56- to -62-, of control -63-
of centering -113- and of blocking -114- , all common to a complete field of machine
dimensions.
7. A machine under the claims 1 to 6 , which is conditionned not to get down the serigraphic
screen -7- on the surface to be printed , unless the machine has run a distance ,
as small as it may be , in its forward sense.
8. A machine under the claims 1 to 7 in which the racks -19- will be mounted with the
teeth -20- downwards to avoid the dust and die drops to soil the teeth flanks and
clamped at each side of them be by lateral finns -80- of the same rack or by indented
clamps fixing the rack at the bottom of their teeth to suited handrails -82- solidary
bolted and rigidizing the printing machine guiding rails and allowing the precise
vertical and horizontal relative calibration between the rails guiding surfaces and
the teeth -20- flanks of each rack.
9. A machine under the claims 1 to 8 in which there are two protection end pannels -58-
and -63- with channels in their lateral inside flanks prepared to receive the careenning
modules -56- lower finns and a protection pannel -56- with a finn in each side and
one or more protection pannels that have a channel and a finn alternatively so matching
with their neigbours by the dovetail joint system and not allowing thus the water
or other liquids to enter inside the espace containing the electric, electronic and
informatic -66- controls the traveling motor -9- and the pneumatic logic elements
as well as the most of electric and pneumatic circuitry , the protection pannel -56-
with a finn in each side being the one to be lifted the first to allow the other pannels
successive rising , the channels being suited to drain liquids if necessary and the
pannels being modular , that is to say , having standard dimensions that , combined
between them made any standard machine width and ,the central ones, are suited one
to support the fan ventilating the translation electric motor ,its electronic controls
and computer hardware and another one the vacuum cleaner
10. A machine under the claims 1 to 9 in which of the two end pannels , the one -63- situated
in the operator's side incorporates the control pannel that contains the programming
keyboard with a liquid cristal screen to display the data introduced by the operator
as well as pneumatic valves and flow and pressure regulators and gauges for the compressed
air feeding the pneumatic devices.
11. A machine under the claims 1 to 10 in which contrary to the until to now practice
with the long table printing carriages , it incorporates as a central informatic unit
a standard unit -66- with disket drive common in the market in which we incorporate
two electronic cards specialy designed for the machine's specific functions , to introduce
with the disked in its memory the desired sequential programming as well as to register
each particular screen printing data in said disket.
12. A machine under the claims 1 to 11 in which the horizontal guiding is provided by
two sets of two ballbearing rollers , which axes , geometricaly contained in a plane
perpendicular to the guiding rail cut themselves with a suited angle to be guided
by said rail , and where for heavy models a multiple set of rollers is used , either
incorporating four rollers -110- in two pairs of two rollers each, or eight rollers
-111- in two pairs of two said sets, all the mounting made combining very rigid supports
-112- with very flexible ones -113- in order to have the necessary rigidity in the
vertical sense -to sustain the weight of the machine- and in the transverse to the
table sense , to secure the precise guidance ,and at the same time to allow the necessary
flexibility to distribute the weigt as evenly as possible over all the rollers.
13. A machine under the claims 1 to 12 in which the beams that form the frame holding
the screen and the ones incorporating the guides for squeegeing can , in some cases
,be disposed for transverse to the table (weft) squeegeing and in other cases be disposed
for longitudinal to the table (warp) squeegeing ,being made in both cases of similar
elements with the exception that in the weft squeegeing the screen is raised by one
or both sides of the machine and in the warp squeegeing the screen is raised by one
or both ends of it.
14. A machine under the claims 1 to 13 in which the squeegeing electric motor -72- have
coupled to its shaft an encoder or resolver -73- of enough resolution, to determine
from the control pannel , thorough the electric motor electronic control the squeegee
stroke and its limits ,to center it correctly over the screen design and allowing
within a certain limits , to stablish the most suitable squeegee speeds and squared
sinus law accelerations and decelerations for each kind of printing
15. A machine under the claims 1 to 14 in which the transverse frontal beam -40- is used
to support in it the vacuum collector -102-that has three narrow ports , -103- -a
central one to aspirate the lint and two adyacent to return the filtered air-, covering
the printing width and situated very close to the surface to be printed ,being the
two upper cylindrical ports of said collector directly connected by two hoses -104-
to the intake of the plane vertical filter -106-and to the exhaust of the vacuum cleaner
which filtering element -107- to retain the aspirated lint consist of a frame covered
with a metalic or plastic monofilament net , who is introduced in its place through
a long and narrow port -108- adequate for easy substitution, cleaning and eyesigth
inspection of its clean condition.
16. A machine under the claims 1 to 15 in which the screen -7- rising and descent is guided
by a device of articulated parallelogram -83- and -84- with a torsion bar -86- and
a lever -87- being all the assembly adjustable to assure the table and screen coplanity
and the needed coincidence at all its points of contact.