DK170148B1

DK170148B1 - Vacuum cleaning system for removing dust, lint or color from a printing press cylinder in an offset printing press

Info

Publication number: DK170148B1
Application number: DK55489A
Authority: DK
Inventors: Charles R Gasparrini; Carl Arnolds
Original assignee: Baldwin Graphic Products
Priority date: 1988-02-08
Filing date: 1989-02-07
Publication date: 1995-06-06
Also published as: DE68901977T2; FI94038C; DK55489A; FI890574A0; EP0328369B1; FI94038B; DE68901977D1; NO890516L; FI890574A; NO890516D0; EP0328369A1; DK55489D0

Description

i DK 170148 B1in DK 170148 B1

Den foreliggende opfindelse angår en offsettrykpresse med et forbedret tørt, mekanisk rensningsanlæg til rensning af en trykdugcylinder i pressen og af den i krav l*s indledning angivne art.The present invention relates to an offset printing press having an improved dry mechanical cleaning system for cleaning a printing press cylinder in the press and of the kind specified in the preamble of claim 1.

5 Offsettrykning er i sammenligning med bogtryk blevet den dominerende trykkemetode indenfor dagbladsindustrien. Dette skyldes tildels den forøgede skarphed af det trykte og evnen til at trykke på mindre glatte overflader, end der kræves til bogtryksmetoden. En anden vigtig faktor for off-10 settrykningens popularitet er ligeledes de lavere omkostninger til de trykplader, som bruges i offsetpresser.5 Compared to letterpress, offset printing has become the dominant printing method in the newspaper industry. This is partly due to the increased sharpness of the print and the ability to print on less slippery surfaces than is required for the printing method. Another important factor for the popularity of off-set printing is also the lower cost of printing plates used in offset printing.

Offsettrykpresser anvender typisk en trykdugcylinder, dvs. en gummicylinder eller en gummidækket cylinder, med det formål at modtage farvetryk fra en trykplade. Det farvede 15 tryk afsættes så på papir, som føres mellem trykdugcylinderen og en modtrykscylinder. Kontinuerlig trykning muliggøres ved at svøbe en trykplade eller et antal trykplader omkring overfladen af en pladecylinder, der er beregnet til rotation i kontakt med trykdugcylinderen.Offset printing presses typically use a blanket cylinder, i.e. a rubber cylinder or a rubber covered cylinder, for the purpose of receiving color printing from a printing plate. The colored 15 print is then deposited on paper which is passed between the blanket cylinder and a backpressure cylinder. Continuous printing is possible by wrapping a printing plate or a plurality of printing plates around the surface of a plate cylinder intended for rotation in contact with the printing cloth cylinder.

20 Ved drift af trykdug-mod-trykdugpresser føres en papirbane mellem to trykdugcylindre monteret således, at den ene trukdugcylinder tjener som en modtrykscylinder for den anden, hvilket medfører samtidig trykning på begge sider af papirbanen.In the operation of press-to-press-press presses, a paper web is passed between two press-cloth cylinders mounted such that one draft-cloth cylinder serves as a back-press cylinder for the other, which results in simultaneous printing on both sides of the paper web.

25 Kontinuerlig offsettrykning påvirkes ugunstigt af støv og fnug fra papirbanen, som er tilbøjelig til at samle sig på trykdugcylinderen eller -cylindrene. Dette støv og fnug forringer kvaliteten af det trykte produkt. Ophobningen af støv, fnug eller farve på en trykdugcylinder frembyder 30 således en alvorlig irritation og nødvendiggør uønsket driftsafbrydelse med henblik på rensning. Problemet er særlig akut i dagblads industrien, når som reaktion på de stigende udgifter til avispapir mindre dyre papirkvaliteter med større fnugindhold ofte erstatter dyrere kvaliteter.25 Continuous offset printing is adversely affected by dust and lint from the paper web, which tends to accumulate on the blanket cylinder (s). This dust and lint degrades the quality of the printed product. Thus, the accumulation of dust, lint or color on a pressurized cylinder 30 causes severe irritation and necessitates undesirable interruption of cleaning. The problem is particularly acute in the newspaper industry when, in response to the rising cost of newsprint, less expensive paper grades with higher lint contents often replace more expensive grades.

35 Et kendt tørt, mekanisk rensningsanlæg er omhandlet i DE offentliggørelsesskrift nr. 3 601 539 og omfatter bør- DK 170148 B1 2 steorganer, organer til at bevæge børsteorganerne mellem en inaktiv stilling i afstand fra cylinderen og en funktionsstilling tæt grænsende til cylinderen for at børste snavs og fnug fra overfladen af cylinderen og fnugfjernelsesorganer 5 i form af en fnugfanger med en åbnelig dør til fjernelse af i afbørstet fnug og snavs.35 A known dry mechanical cleaning system is disclosed in DE Publication No. 3 601 539 and includes brush means, means for moving the brush means between an inactive position away from the cylinder and a position close to the cylinder for brushing. dirt and lint from the surface of the barrel and lint removal means 5 in the form of a lint trap with an open door for removing brushed lint and dirt.

Det er ligeledes kendt at anvende fugtige vakuumanlæg til fjernelse af snavs fra cylindre.It is also known to use moist vacuum systems to remove dirt from cylinders.

I et sådant fugtigt anlæg neddykkes segmenter af 10 trykdugcylinderen kontinuerligt i og renses med et opløsningsmiddel. Det overskydende opløsningsmiddel fjernes så med en visker med et vakuumhoved grænsende til viskerbladet.In such a humid plant, segments of the pressurized cylinder are continuously immersed in and purified with a solvent. The excess solvent is then removed with a wiper with a vacuum head adjacent to the wiper blade.

Se f.eks. US patentskrift 3 835 779. Et andet fugtigt anlæg er omhandlet i US patentskrift nr. 1 378 278.See, e.g. U.S. Patent No. 3,835,779. Another moist plant is disclosed in U.S. Patent No. 1,378,278.

15 Den foreliggende opfindelse undgår behovet for opløs ningsmidler ved at anvende et fuldstændig tørt anlæg til fjernelse af snavs, og til forskel fra tidligere tørre anlæg behøves eller anvendes der ingen konventionel fnugfanger.The present invention avoids the need for solvents by using a completely dry system for removing dirt, and unlike conventional dry systems, no conventional lint trap is needed or used.

Den foreliggende opfindelse er ejendommelig ved, at 20 fjernelsesorganerne indbefatter et hus, i hvilket børsteorganerne er monteret, idet huset sammen med cylinderen i en funktionsstilling afgrænser et delvis evakuerbart kammer, og en vakuumkilde til delvis evakuering af kammeret for derved at fjerne snavs og fnug fra trykdugcylinderen.The present invention is characterized in that the removing means include a housing in which the brush means are mounted, the housing together with the cylinder defining a partially evacuable chamber and a vacuum source for partially evacuating the chamber thereby removing dirt and lint from the housing. blanket cylinder.

25 Trykdugcylinderen kan renses under forløbet af en pressekørsel uden at afbryde pressefunktionen eller forårsage spild under kørslen. Dette tillader en skarpere reproduktion af et trykprodukt og involverer mindre stilstandstid. Det tillader ligeledes anvendelse af kvaliteter af papirmateriale 30 med større fnugindhold.25 The pressurized cylinder can be cleaned during the course of a press run without interrupting the press function or causing wastage during the run. This allows for a sharper reproduction of a print product and involves less downtime. It also allows the use of grades of paper material 30 with greater lint content.

Rensningsanlægget er egnet til integreret sammenbyg- * ning med en offsetpresse eller til fremstilling som en tilføjelsesanordning, der kan efter installeres på en eksisteren-de presse.The purification plant is suitable for integrated assembly with an offset press or for manufacture as an additive which can subsequently be installed on an existing press.

35 Rensningsanlægget er egnet til automatisk funktion med en indgrebsfrekvens, som kan indstilles af en presseope- DK 170148 B1 3 ratør.35 The purifier is suitable for automatic operation with an engagement frequency which can be set by a press operator.

Frekvensen af den automatiske indgriben og funktionen af trykdugsrensningsanlægget kan således indstilles af presseoperatøren som reaktion på forskellige forventede eller 5 observerede driftsparametre såsom længden af trykningsperioden og fnugindholdet i papirmaterialet.Thus, the frequency of the automatic intervention and operation of the pressurized cleaning system can be set by the press operator in response to various expected or observed operating parameters such as the length of the printing period and the lint content of the paper material.

Opfindelsen skal i det følgende beskrives nærmere ud fra foretrukne udførelsesformer, idet der henvises til tegningen, på hvilken 10 fig. 1 viser en perspektivisk gengivelse fra siden og til dels i tværsnit af én udførelsesform for et vakuumtryk-dugsrensningsanlæg ifølge den foreliggende opfindelse, fig. 2 set fra siden vakuumtrykdugsrensningsanlægget i anliggende stilling, 15 fig. 3 set fra siden vakuumtrykdugsrensningsanlægget i den udkoblede stilling, fig. 4 i større målestok set fra siden og i tværsnit børsteenheden, fig. 5 set forfra og i tværsnit en børsteenhed med 20 opdelte børster, og fig. 6 set forfra og i tværsnit en børsteenhed med i sideretningen indstillelige børster.The invention will now be described in more detail with reference to preferred embodiments, with reference to the drawing, in which: 1 is a side elevational and partial cross-sectional view of one embodiment of a vacuum press fabric cleaning system of the present invention; FIG. 2 is a side view of the vacuum pressurized cleaning system in abutting position; FIG. 3 is a side view of the vacuum pressurized cleaning system in the switched-off position; FIG. 4 is an enlarged side view of the brush unit; FIG. 5 is a front and cross-sectional view of a brush unit with 20 divided brushes; and FIG. 6 is a front view and in cross section a brush unit with laterally adjustable brushes.

Fig. 1 viser en tør trykdugsrenser ifølge en udførelsesform for den foreliggende opfindelse. Trykdugsrenseren, 25 der i almindelighed er betegnet med 20, indbefatter en børsteenhed 21 dannet af mindst én børste 24 og et ikke vist vakuumorgan.FIG. 1 shows a dry press cloth cleaner according to an embodiment of the present invention. The blanket cleaner 25, generally designated 20, includes a brush assembly 21 formed by at least one brush 24 and a vacuum means not shown.

Trykdugsrenseren ifølge denne udførelsesform for den foreliggende opfindelse er monteret i funktionel tilknytning 30 til en trykdugcylinder 28 hovedsagelig parallelt med længdeaksen for trykdugcylinderen. Trykdugsrensermonteringskon-soller 30 er befæstet til det ikke viste pressestativ hovedsagelig udenfor begge ender af trykdugcylinderen 28. Svingarme 34 forbinder trykdugsrenseren 20 med monteringskonsol-35 lerne 30. Disse svingarme 34 tjener til at bære trykdugs-renseen 20 og er svingelige omkring tappe 36.The press cloth cleaner according to this embodiment of the present invention is mounted in functional connection 30 to a press fabric cylinder 28 substantially parallel to the longitudinal axis of the press fabric cylinder. Pressure cleaner assembly brackets 30 are attached to the press frame not shown, mainly outside both ends of the presser barrel 28. Swing arms 34 connect the presser cleaner 20 to the mounting brackets 30. These pivot arms 34 serve to carry the presser cleaner 20 and are pivotable about pins 36.

DK 170148 B1 4DK 170148 B1 4

Trykdugsrenseene er generelt svingelig mellem to funktionsstillinger. Svingning af de nævnte arme 34 mellem disse stillinger bevirkes af et antal aktivatorer 38 befæstet til svingarmene 34. Fortrinsvis er den anvendte aktivator 5 en pneumatisk aktivator, selv om elektriske eller hydrauliske 4 aktivatorer om ønsket kan anvendes. Konventionelt anvendes trykluft, fordi det sædvanligvis er til rådighed i presse-lokalet, mens elektriske eller hydrauliske kilder ikke er.Pressure cleaning is generally pivotal between two operating positions. Swinging of said arms 34 between these positions is effected by a number of activators 38 attached to the swing arms 34. Preferably, the activator 5 used is a pneumatic activator, although electrical or hydraulic 4 activators can be used if desired. Conventionally, compressed air is used because it is usually available in the press room while electrical or hydraulic sources are not.

I den første funktionsstilling trykkes trykdugsrenseren 20 10 bort fra trykdugscylinderen 28 for f.eks. at muliggøre udskiftning af børsterne, reparation eller vedligeholdelse af maskinen og/eller ændring af banen.In the first operating position, the blanket cleaner 20 10 is pushed away from the blanket cylinder 28 for e.g. to allow brush replacement, repair or maintenance of the machine and / or changing the web.

I den anden funktionsstilling holdes trykdugsrenseren 20 i kontakt med overfladen af trykdugcylinderen 28. I denne 15 anden stilling kan trykdugsrenseren bevirke rensning og fjernelse af fnug og snavs fra trykdugcylinderen.In the second operating position, the blanket cleaner 20 is kept in contact with the surface of the blanket cylinder 28. In this second position, the blanket cleaner can effect the cleaning and removal of lint and dirt from the blanket cylinder.

Vakuumdelen af den første udførelsesform for trykdugsrenseren 20 består generelt af ét i det væsentlige U-formet hus 40, der strækker sig langs længden af trykdug-20 cylinderen, og en børsteenhed 22. Børsteenheden 22 er monteret inden i huset 40, som igen er monteret på svingarmene 34. Huset 40 indbefatter børster 24, som fastholdes i en børsteholder 25, der er udtageligt monteret i huset 40 på en hvilken som helst bekvem måde og let kan udskiftes efter 25 behov. Børsterne 24 kan som vist være monteret i par og have en forholdsvis lang levetid. Kontinuerlig funktion vil imidlertid kræve udskiftning og vedligeholdelse af børsterne.The vacuum portion of the first embodiment of the blanket cleaner 20 generally consists of one substantially U-shaped housing 40 extending along the length of the blanket 20 cylinder and a brush unit 22. The brush unit 22 is mounted within the housing 40 which is again mounted on the swing arms 34. The housing 40 includes brushes 24 which are retained in a brush holder 25 which is removably mounted in the housing 40 in any convenient manner and can be easily replaced as needed. The brushes 24 may, as shown, be mounted in pairs and have a relatively long life. However, continuous operation will require replacement and maintenance of the brushes.

I fig. 5 og 6 er vist to alternative udførelsesformer 30 for børsteenheden. X fig. 5 er børsteholderen 62 opdelt for at tillade, at de enkelte afsnit løftes, så at de ikke be- „ rører trykdugcylinderen under rensning. Opdeling kan være ønskelig, eftersom avistrykdugcylindre i almindelighed er opsat i kvarte eller sider, dvs. at en bane kan have dobbelt 35 bredde (hel trykdug) eller enkelt bredde (halv trykdug).In FIG. 5 and 6, two alternative embodiments 30 of the brush unit are shown. X fig. 5, the brush holder 62 is divided to allow the individual sections to be lifted so that they do not touch the blanket cylinder during cleaning. Splitting may be desirable since newspaper cloth cylinders are generally set up in quarters or pages, i.e. that a web may have double the width of 35 (full press cloth) or single width (half press cloth).

Hvis der anvendes en enkelt bredde, kan der komme farve på DK 170148 B1 5 den cylinder, som ikke er dækket af banen. Når dette forekommer, kan farve tilstoppe de sammenhængende børster i området uden bane. Opdeling af børsterne, fortrinsvis i fire afsnit, tillader, at børsterne i det uanvendte område løftes 5 bort.If a single width is used, color may occur on the cylinder not covered by the web. When this occurs, color can clog the cohesive brushes in the area without trajectory. Splitting the brushes, preferably into four sections, allows the brushes in the unused area to be lifted 5 away.

I den i fig. 5 viste udførelsesform udføres løftning ved manuelt at bevæge en vægtarm 64 i en løfteenhed 65 til den øverste stilling. Dette virker til at løfte en styrestang 66, der er befæstet til børsteholderen 62, og trykke dette 10 afsnit af børsteholderen bort fra trykdugcylinderen. Børsteenheden kan være opdelt i så mange afsnit som ønsket for at tilvejebringe maksimal alsidighed. I almindelighed dækker opdeling af børsteenheden i fire afsnit de fleste funktioner. Ligeledes kan løftning udføres ved et hvilket som helst 15 effektivt middel og kan ske enten manuelt som vist eller med automatiske eller halvautomatiske midler.In the embodiment shown in FIG. 5, lifting is carried out by manually moving a weight arm 64 in a lifting unit 65 to the upper position. This acts to lift a guide rod 66 attached to the brush holder 62 and push this 10 sections of the brush holder away from the press fabric cylinder. The brush unit can be divided into as many sections as desired to provide maximum versatility. In general, dividing the brush unit into four sections covers most functions. Also, lifting can be performed by any effective means and can be done either manually as shown or by automatic or semi-automatic means.

Når det drejer sig om kommercielle banepresser, kan opdeling af børsterne eventuelt ikke være mulig. Dette er fordi den bane, som der trykkes på, kan variere meget i 20 bredde. Til sådanne anvendelser kan børsteenheden gøres indstillig i sideretningen langs bredden af trykdugcyl inderen (se fig. 6). I den i fig. 6 viste udførelsesform er en børsteholder 68 forskydeligt monteret indeni et hus 70 langs slidser 72. Låseorganér 74 tjener til at holde børsterne i 25 den ønskede placering i sideretningen. I den i fig. 6 viste udførelsesform anvendes vingemøtrikker til at låse børsterne i den ønskede placering. På denne måde kan børsterne oprettes til den specielle anvendelse, der skal udøves.When it comes to commercial web presses, splitting the brushes may not be possible. This is because the web that is pressed on can vary widely in 20 widths. For such applications, the brush assembly can be adjusted in the lateral direction along the width of the blanket cylinder (see Fig. 6). In the embodiment shown in FIG. 6, a brush holder 68 is slidably mounted inside a housing 70 along slots 72. Locking means 74 serve to hold the brushes in the desired lateral position. In the embodiment shown in FIG. 6, wing nuts are used to lock the brushes in the desired location. In this way, the brushes can be created for the special application to be exercised.

Der kan anvendes en række forskellige materialer til 30 børsterne 24, forudsat at de ikke beskadiger overfladen af trykdugcylinderen 28. Disse materialer indbefatter både naturlige og syntetiske fibre. Ligeledes kan børsterne 24 være monteret under en vinkel på indtil 90* med tangenten til overfladen af trykdugcylinderen for at forbedre deres 35 evne til at løsne og fjerne fnug og andet snavs fra overfladen.A variety of materials can be used for the brushes 24, provided they do not damage the surface of the printing barrel 28. These materials include both natural and synthetic fibers. Likewise, the brushes 24 may be mounted at an angle of up to 90 ° with the tangent to the surface of the pressurized cylinder to enhance their ability to loosen and remove fluff and other debris from the surface.

DK 170148 B1 6DK 170148 B1 6

Huset 40 i form af en omvendt U-formet kanal har en øvre flade 44 og parallelle sider henholdsvis 46 og 48.The housing 40 in the form of an inverted U-shaped channel has an upper surface 44 and parallel sides 46 and 48 respectively.

Huset 40 er monteret mellem svingarmene 34 i en nedadven-dende stilling med den åbne ende vendende imod trykdugcy- * 5 linderen 28. Alternativt kan den U-formede kanal 40 efter ønske være monteret foran eller bagved i forhold til midter-linien af trykdugcylinderen 28. Fig. 4 viser f.eks. en udførelsesform, hvor børsterne er monteret foran for midterlinien af trykdugcylinderen.The housing 40 is mounted between the pivot arms 34 in a downward-facing position with the open end facing the pressurized cylinder 28. Alternatively, the U-shaped channel 40 may be mounted in front or rear as desired at the center line of the pressurized cylinder 28. FIG. 4 shows e.g. an embodiment in which the brushes are mounted in front of the center line of the blanket cylinder.

10 Mindst én børste 24 er monteret til den øvre flade 44 af huset 40 via børsteholderen 25 og i det væsentlige parallel med siderne 44 og 48, så at børsterne, når renseren er i funktion, berører overfladen af cylinderen og løsner snavs og fnug, der tilbageholdes inde i huset. Alternativt 15 kan et antal børster være anbragt i rækker eller søjler inden i huset 40 til brug ved løsning af fnug og snavs fra overfladen af trykdugcylinderen 28.At least one brush 24 is mounted to the upper surface 44 of the housing 40 via the brush holder 25 and substantially parallel to the sides 44 and 48 so that when the cleaner is in operation, the brushes touch the surface of the cylinder and loosen dirt and lint which detained inside the house. Alternatively, a plurality of brushes may be arranged in rows or columns within the housing 40 for use in loosening dirt and debris from the surface of the pressurized cylinder 28.

Bøjelige viskere 50 er anbragt ved enderne af siderne 46 og 48 i huset 40 og tjener til at berøre overfladen af 20 trykdugcylinderen 28 for at tilvejebringe tætningsoverflader i berøring med trykdugcylinderen, når trykdugsrenseren er i anlæg. Disse viskere tjener ligeledes det sekundære formål at løsne og fjerne fnug og snavs 52 fra overfladen af trykdugcylinderen 28.Flexible wipers 50 are disposed at the ends of sides 46 and 48 of housing 40 and serve to touch the surface of the pressurized cylinder 28 to provide sealing surfaces in contact with the pressurized cylinder when the pressurized cleaner is in contact. These wipers also serve the secondary purpose of loosening and removing lint and debris 52 from the surface of the blanket cylinder 28.

25 Løsnede fnug og løsnet snavs 52 fjernes fra det indre af huset 40 ved hjælp af et passende vakuumanlæg. En ikke vist vakuumfrembringelsesmaskine er forbundet til en vakuumtilslutning 58 i huset 40 ved hjælp af en slange 56. Fnug og snavs 52 ledes gennem slangen 56 ved hjælp af vakuumet for 30 at blive opsamlet i en passende, ikke vist opsamlingsenhed.25 Loose fluff and loosened dirt 52 are removed from the interior of housing 40 by a suitable vacuum system. A vacuum generation machine (not shown) is connected to a vacuum connection 58 in the housing 40 by means of a hose 56. Fluff and dirt 52 are passed through the hose 56 by means of the vacuum to be collected in a suitable collection unit (not shown).

I fig. 2-4 er vist den almindelige funktion af tryk- ^ dugsrenseren i forbindelse med en trykdug-mod-trykdugspresse-udførelsesform for den foreliggende opfindelse. En bane 60 af trykmateriale passerer mellem modsat roterende trykdug-35 cylindre 28 og påtrykkes på både for- og bagside af banen.In FIG. 2-4 are shown the general function of the printing press cleaner in connection with a printing press against printing press embodiment of the present invention. A web 60 of printing material passes between opposite rotary printing web cylinders 28 and is applied to both the front and back of the web.

I løbet af denne trykningsoperation opsamles fnug og snavs DK 170148 B1 7 52 fra banen 60 på overfladen af trykdugcylindrene 28 og ville, hvis det fik lov til at blive derpå, være tilbøjeligt til at forringe den samlede kvalitet af det trykte produkt.During this printing operation, fluff and debris are collected from the web 60 on the surface of the blanket cylinders 28 and would, if allowed to do so, tend to degrade the overall quality of the printed product.

Med henblik på at fjerne disse fnug og snavset fra 5 overfladen af trykdugcylindrene 28 trykkes trykdugsrensere 20, i almindelighed placeret ovenpå trykdugcylindrene 28, imod cylindrene med trykorganer i form af aktivatorer 38. I almindelighed er det ikke nødvendigt, at trykdugsrenserne 20 til stadighed er i berøring med trykdugcylindrene 28 10 under trykningen, hvor en stor mængde fnug og snavs samler sig forholdsvis hurtigt. Det kan imidlertid være ønskeligt at efterlade dem i indgreb under funktionen af pressen. Under normale driftsbetingelser aktiveres trykdugsrenserne 20 periodisk imod trykdugscylindrene i et forud fastlagt 15 tidsrum for at bevirke rensning af overfladen.In order to remove these lint and dirt from the surface of the blanket cylinders 28, blanket cleaners 20, generally located on top of the blanket cylinders 28, are pressed against the cylinders with pressure means in the form of activators 38. Generally, it is not necessary that the blanket cleaners 20 be constantly in place. contact with the blanket cylinders 28 10 during printing, where a large amount of fluff and dirt accumulate relatively quickly. However, it may be desirable to leave them engaged during the operation of the press. Under normal operating conditions, the blanket cleaners 20 are periodically activated against the blanket cylinders for a predetermined period of time to effect surface cleansing.

Periodisk funktion af trykdugsrenseren ifølge den foreliggende opfindelse kan styres af konventionelle tidsstyringsmekanismer knyttet enten til pressens rotation eller på kommando af operatøren. I hvert tilfælde styres funktionen 20 af aktivatoren således, at når man ønsker trykdugsrensning, betjenes aktivatoren 38, så at renseren bevæges fra den udkoblede stilling (fig. 3) til den indkoblede stilling (fig. 2). I den indkoblede stilling bringes børsterne 24 i børsteenheden 22 i berøring med overfladen af trykdugcylin-25 deren 28. Børsterne 24 anvendes til at børste trykdugcylinderen 28, og efter et forud fastlagt antal omdrejninger betjenes aktivatoren 38 for at få børsteenheden 22 til at udkoble som vist i fig. 3.Periodic operation of the press cloth cleaner of the present invention can be controlled by conventional timing mechanisms associated either with the rotation of the press or at the command of the operator. In each case, the function 20 is controlled by the actuator so that when desirous cleaning is desired, actuator 38 is operated so that the cleaner moves from the switched-off position (Fig. 3) to the switched-on position (Fig. 2). In the engaged position, the brushes 24 in the brush unit 22 are brought into contact with the surface of the blanket cylinder 25. The brushes 24 are used to brush the blanket cylinder 28 and, after a predetermined number of turns, the activator 38 is operated to cause the brush unit 22 to disengage as shown. in FIG. Third

Mens den er indkoblet, afsuges fnug og snavs, som er 30 løsnet og flyttet af børsterne 24 og i en vis grad af viskerne, og deponeres af vakuumanlægget. Dette fjerner effektivt fnug og snavs fra trykdugcylinderen under trykningen.While switched on, fluff and debris, which have been loosened and moved by the brushes 24 and to some extent by the wipers, are sucked off and deposited by the vacuum system. This effectively removes lint and debris from the printing press cylinder during printing.

Den særlige udførelsesform, som netop er beskrevet, foretrækkes på grund af den lette installation og indstil-35 ling, som frembydes af den beskrevne konstruktion. F.eks. er de forskellige arbejdende dele placeret fysisk ovenover DK 170148 B1 8 trykdugcylinderne 28 og er således let tilgængelige både med henblik på installation og vedligeholdelse. Andre placeringer er forenelige med det bredere aspekt af den foreliggende ^ opfindelse. Det er imidlertid klart, at ved at udnytte bør-5 steenheden 22 i forbindelse med vakuumorganet 56 undgås behovet for den fnugsamlerenhed, som anvendes i den kendte teknik.The particular embodiment just described is preferred because of the ease of installation and adjustment provided by the described construction. For example. For example, the various working parts are physically located above the press fabric cylinders 28 and are thus readily available both for installation and maintenance. Other locations are compatible with the broader aspect of the present invention. However, it will be appreciated that by utilizing the brush assembly 22 in conjunction with the vacuum means 56, the need for the lint collector assembly used in the prior art is avoided.

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Claims

An offset printing press including a blanket cylinder (28) and a dry mechanical cleaning system for the cylinder, the cleaning unit including a brush member (24), means (38) for moving the brush member between an inactive position away from the blanket cylinder (28) and a functional position. adjacent the cylinder for brushing dirt and lint from the surface of the pressurized cylinder and means (40.56) for removing brushed dirt and lint, characterized in that the removal means include a housing (40) in which the brush means are mounted, which housing together with the cylinder in the operative position, delimits a partially evacuable chamber, and a vacuum source (56) for partially evacuating the chamber, thereby removing the dirt and lint from the pressurized cylinder.

Apparatus according to claim 1, wherein the offset printing press includes a press stand with a press cloth cylinder (28) mounted thereon, characterized by a press cloth mounting frame (30) attached to the press stand adjacent 20 to the press cloth cylinder and arm means (34) movably connecting the mounting frame with the press frame. (40) is attached to the movable arm members (34).

Apparatus according to claim 2, characterized in that the brush housing (40) is substantially U-shaped in cross-section and extends longitudinally along the length of the pressurized cylinder to enclose a portion of the surface of the pressurized cylinder in the operating position.

Apparatus according to any one of the preceding claims, characterized in that it includes means (50) extending from the housing (40) for contact with the blanket cylinder (28) to provide a sealing surface between the blanket cylinder and the housing in the operating position. .

Apparatus according to any one of the preceding claims, characterized in that the brush members comprise 35 brushes (62) divided into sections, which sections are separately movable between positions in which they engage and DK 170148 B1 out of engagement with the printing cloth cylinder.

Apparatus according to claim 5, characterized in that the brushes have a shorter length than the housing (40) and are adjustable with respect to their position in the housing.

Apparatus according to claim 5 or 6, characterized in that the brushing means includes a pair of linear * brushes (62) which are removably mounted in the housing.

Apparatus according to any one of the preceding claims, characterized in that it includes pneumatically driven moving means (38) for moving the brush means (24) between the operating position and the inactive position. 15 20 25 30 o 35 V