EP1225046A1 - Printing cylinder for accomodating a printing sleeve - Google Patents

Abstract

Outer surface of rubber blanket cylinder (10) has air holes or air jets (14) and air supply with through-flow limiter to alter air flow according to axial position of rubber blanket (12) to prevent blanket sticking to cylinder. Limiter creates eddy if opening is not covered by print sleeve. Additional row of air holes or air jets (16) is provided, axially arranged between first row (14), nearer to drive side, to help in putting blanket on and taking off blanket. Independent claim for method of axially positioning or displacing rubber blanket sleeve on cylinder.

Description

The present invention relates to a pressure cylinder for receiving an axially positionable and / or axially displaceable pressure sleeve according to the preamble of Claim 1.

Furthermore, the present invention relates to a method for axial positioning and / or moving a printing sleeve on a printing cylinder according to the preamble of claim 14.

Tubular or sleeve-shaped pressure sleeves, e.g. Blankets for the Offset printing as described in US 5,215,013 are applied axially to a cylinder applied and removed from this. As for a rubber blanket in that Described patent are usually openings or air holes on the Operator side of the blanket cylinder arranged to apply pressure to the inside of the Blanket to act on when the blanket is axially from the blanket cylinder removed or applied to it.

Blankets, however, can stick if they remain attached for too long because Air pressure from the air holes can be blocked and the drive side of the cylinder do not reach. In addition, the placement of holes is due to use difficult only a series of air holes on the operator side; it could also happen that the sleeve does not inflate or expand at all. Holes not placed correctly can cause air to simply escape from the operator side of the sleeve without the Inflate and expand the drive side of the sleeve.

It may also be desirable to have several blankets side by side on one to apply a single blanket cylinder. A single row of holes on the Operator can inflate only one of the blankets on operator side, so that other blankets closer to the drive side cannot be removed.

Attempts have been made to create additional air holes along the body of the impression cylinder to place. However, the sleeve is in a partially removed or attached position Position, the openings or vents remain uncovered while the vents are open operator side are covered. This leads to a large reduction in pressure if the air emerges from the uncovered holes and the flow at the holes of the Operator side subsides, so placing or removing the rubber blanket becomes more difficult or impossible. Thus the additional holes require the Use of many installation devices to properly control the air flow. These features tend to be expensive and complicated, particularly because of the cylinder has to turn.

In a textbook from 1981 entitled "Non-Contact Seals" the authors describe labyrinth seals in which the fluid flow is based on vortices can be blocked or reduced. 3-56 on pages 174-176 Effect of the placement of fins in airflow and vortex generation shown. The use of these seals in printing machines or in printing cylinders will not discussed.

From US 5,797,531 is a turning bar pressurized with compressed air, which e.g. in the Folder superstructure of a rotary printing press can be used, known which are arranged adjacent on their peripheral surface in the axial direction Has air outlet openings from which blown air emerges and between the surface an air cushion to the turning bar and a paper web guided around the turning bar non-contact transport of the paper web builds up. The individual air outlet openings The turning bar are provided with valves, the valves having two switching states can take. In the first state in which the air outlet opening is not one The paper web is covered, blown air exits through a duct in the valve, while the valve itself closes the air outlet opening and thus a reinforced one Blowing air prevented. In the second state, in which the Air outlet openings are covered by a paper web, it occurs as a result of getting under the compressed air cushion building up the paper web and the associated increased Air pressure to open the valve so that more blowing air than in the first state through the air outlet openings in the area between the paper web and the Surface of the turning bar.

Furthermore, a device for treating webs is known from US 2,828,553, wherein a roller with air outlet openings arranged on the circumference of the roller is provided and is used to transport a train. The air outlet openings can be equipped with ball valves, the ball valves being designed such that a contact of the web with a section of the ball valve, which extends over the Surface of the roller extends beyond, to a displacement of the ball within the Valve leads, which moves the valve from a closed to an open state transforms.

It is therefore an object of the present invention to apply a fluid To create air cylinder for receiving a pressure sleeve, with which one enables trouble-free positioning, sliding and / or removal of a pressure sleeve becomes.

Another object of the present invention is fluid assisted removal or applying more than one printing sleeve to the printing cylinder in a trouble-free manner Way to enable.

In addition, it is an object of the present invention to provide a method which makes it possible to position a printing sleeve axially on a printing cylinder and / or to postpone, whereby faults, in particular a sticking of the pressure sleeve should be avoided.

According to the invention, these tasks are achieved by the features of the independent Claims 1 and 14 solved.

The impression cylinder according to the invention, in particular a blanket cylinder, for receiving an axially positionable and / or axially displaceable pressure sleeve, in particular Blanket sleeve, with a cylinder body having an outer surface, wherein the outer surface comprises at least one opening, and with a feed, in particular a supply line for supplying fluid, in particular air, to the at least one opening, is characterized in that the supply at least has a flow limiter, which the fluid flow depending on the changed axial position of the pressure sleeve.

In the manner according to the invention, the fluid flow through at least one Flow limiter changed depending on the axial position of the pressure sleeve, whereby the jamming of the pressure sleeve can be prevented in an advantageous manner. If the at least one opening on the outer surface of the printing cylinder from the Pressure sleeve covered, the flow limiter enables the escape of fluid, especially air, for the trouble-free positioning or displacement of the pressure sleeve, in the other case, if the opening is not covered by the pressure sleeve, the Flow limiter advantageously the fluid flow through the supply or out limited or even reduced the opening in the surface of the impression cylinder, so that on a simple way to avoid a drop in pressure due to the fluid flowing out unchecked can. As a result, the pressure drop in a connected to the pressure cylinder Fluid reservoir, e.g. a compressed air tank, and the Sizing of the compressed air supply while saving costs and Maintenance work can be reduced. The flow restrictor, which limits the fluid flow in Changes depending on the axial position of the pressure sleeve can thus be advantageous for automatic flow control in the feed or in the opening of the Surface of the impression cylinder. As a result, in advantageously on a complex compressed air supply system, in particular on a Control device and sensors are dispensed with.

According to the invention, a printing sleeve, which is pushed onto the printing cylinder or is removed from it, regardless of its current position on the impression cylinder always with the necessary amount of compressed air through the opening in the surface of the Pressurized pressure cylinder and thereby ensures that the pressure sleeve in necessary stretched, and a trouble-free and reduced friction Moving the pressure sleeve is advantageously possible.

The printing cylinder according to the invention also has the advantage that the Flow restrictor vortex generated when the at least one opening at least is not partially covered by the pressure sleeve.

Due to the automatic formation of eddies, switching elements in Connection with the flow limiter can be dispensed with, which is advantageous to reduce operating costs by avoiding wearing parts leads.

It can further be provided that the flow limiter has a plurality of Has slats.

A flow limiter with a large number of fins is simple producible and insertable into the surface of the printing cylinder. This allows one simple construction of the flow limiter without moving parts using the Flow conditions inside the flow restrictor generating Fluid vortex can be caused.

In a further embodiment of the invention, the ends can be one another opposite slats be spaced such that they have a free channel for the Form fluid flow.

It can further be provided that the flow limiter prevents flow Objects and / or textile material and / or fiber material includes.

In addition, the flow restrictor can comprise a valve which, depending on the axial position of the pressure sleeve is open or at least largely closed.

It is also possible in an advantageous manner to open the openings or the feeders to provide pressure cylinder according to the invention with valves, which like the above mentioned vortex generating flow limiter depending on the axial Position of the pressure sleeve limit the flow of fluid, in particular air. A device is also used when using valves to limit the flow provided which the displacement of a pressure sleeve without problems and allows for reduced friction in any position of the pressure sleeve. In advantageous Additional control devices and sensors can thus be dispensed with become.

The at least one opening may comprise a plurality of openings which are in Circumferential direction offset on the outer surface of the cylinder body are.

According to a further embodiment of the invention, the plurality of openings is assigned to a pressure sleeve.

It can further be provided that the at least one opening has a plurality of Includes openings which are offset in the axial direction on the outer surface of the Cylinder body are arranged.

It is also advantageous if the plurality of openings have different pressure sleeves assigned.

In a further embodiment of the printing cylinder according to the invention, at least one of the plurality of openings assigned to a first pressure sleeve and at least one further assigned to the plurality of openings of a further pressure sleeve, the Pressure sleeves can be positioned axially offset on the pressure cylinder.

According to a further embodiment of the invention, the at least one opening be arranged in the region of the drive-side end section of the printing cylinder and in The area of the operator-side end section of the printing cylinder can have further openings be arranged.

A printing press according to the invention, in particular offset printing press or Web-fed rotary offset printing machine, with a compressed air supply, is characterized by a first impression cylinder and at least one second impression cylinder as above described from.

A method according to the invention for axially positioning and / or moving one Printing sleeve, in particular blanket sleeve, on a printing cylinder, in particular Blanket cylinder, the impression cylinder having an outer surface comprises at least one opening having a cylinder body, and wherein one Supply, in particular a supply line, for supplying fluid, in particular Air to which at least one opening is provided is distinguished by providing fluid pressure on an inside of the pressure sleeve by means of the at least an opening, axial displacement or positioning of the pressure sleeve, and automatic Limiting the flow through the at least one opening by means of a Flow limiter, which determines the fluid flow depending on the axial position of the Pressure sleeve changed, off.

The method according to the invention is accompanied by advantages such as those above have been described with regard to the printing cylinder according to the invention.

It can further be provided that the step of automatically limiting the Flow includes the formation of fluid vortices.

It is also advantageous that the step of automatically limiting the flow includes at least largely closing a valve.

The invention is more preferred below with reference to the drawings Embodiments described.

Fig. 1

eine schematische Ansicht einer erfindungsgemäßen Offsetdruckmaschine, in der eine einzelne Luftquelle, z.B. ein Kompressor, vier verschiedene Gummituchzylinder versorgt,

Fig. 2

einen erfindungsgemäßen Gummituchzylinder für ein einzelnes Gummituch,

Fig. 3

einen erfindungsgemäßen Gummituchzylinder für mehrere Gummitücher,

Fig. 4a und 4b

eine erste Ausführungsform eines erfindungsgemäßen Durchflussbegrenzers für die durchflussbegrenzten Öffnungen bzw. Luftlöcher des Zylinders, wobei in Fig. 4a ein Gummituch über dem Loch angeordnet ist, und in Fig. 4b das Gummituch nicht über dem Loch angeordnet ist,

Fig. 5

eine weitere Ausführungsform des erfindungsgemäßen Durchflussbegrenzers des Zylinders,

Fig. 6

eine weitere Ausführungsform des erfindungsgemäßen Durchflussbegrenzers des Zylinders,

Fig. 7a und 7b

eine Draufsicht und eine Seitenansicht einer weiteren Ausführungsform des erfindungsgemäßen Durchflussbegrenzers des Zylinders, wobei Fig. 7a die Ansicht durch den Schnitt VI a - VI a von Fig. 7b und Fig. 7b die Ansicht durch den Schnitt VI b - VI b aus Fig. 7a zeigt,

Fig. 8a und 8b

eine Draufsicht und eine Seitenansicht einer weiteren Ausführungsform des erfindungsgemäßen Durchflussbegrenzers des Zylinders, wobei Fig. 8a die Ansicht durch den Schnitt VII a - VII a von Fig. 8b und Fig. 8a die Ansicht durch den Schnitt VII b - VII b von Fig. 8a zeigt,

Fig. 9

eine weitere Ausführungsform des erfindungsgemäßen Durchflussbegrenzers des Zylinders, und

Fig. 10

eine weitere Ausführungsform eines erfindungsgemäßen Durchflussbegrenzers in Form eines Kugelventils.

The drawings show:

Fig. 1

1 shows a schematic view of an offset printing machine according to the invention, in which a single air source, for example a compressor, supplies four different blanket cylinders,

Fig. 2

a blanket cylinder according to the invention for a single blanket,

Fig. 3

a blanket cylinder according to the invention for several blankets,

4a and 4b

1 a first embodiment of a flow limiter according to the invention for the flow-limited openings or air holes of the cylinder, a rubber blanket being arranged above the hole in FIG. 4a and the rubber blanket not being arranged above the hole in FIG. 4b,

Fig. 5

another embodiment of the flow limiter of the cylinder according to the invention,

Fig. 6

another embodiment of the flow limiter of the cylinder according to the invention,

7a and 7b

a plan view and a side view of a further embodiment of the flow limiter of the cylinder according to the invention, FIG. 7a the view through the section VI a - VI a of FIG. 7b and FIG. 7b the view through the section VI b - VI b from FIG. 7a shows,

8a and 8b

a plan view and a side view of a further embodiment of the flow limiter of the cylinder according to the invention, FIG. 8a the view through the section VII a - VII a of FIG. 8b and FIG. 8a the view through the section VII b - VII b of FIG. 8a shows,

Fig. 9

a further embodiment of the flow limiter of the cylinder according to the invention, and

Fig. 10

a further embodiment of a flow limiter according to the invention in the form of a ball valve.

Fig. 1 shows a schematic view of the drive side of an inventive Offset printing machine 1. A web 5 runs through a nip, which is from a first sleeve-shaped rubber blanket 12 and a second sleeve-shaped rubber blanket 62 is formed, and then through a second gap formed by a third sleeve-shaped rubber blanket 112 and a fourth sleeve-shaped rubber blanket 162 is formed. The blanket 12 is axially attached to a blanket cylinder 10, the Flow restrictor, as described with reference to FIG. 2, includes Blanket 62 is axially attached to a similar blanket cylinder 59. The Plate cylinders 8, 58 contact the rubber blankets 12, 62, respectively, for a colored one Create image on the rubber blankets, the image then transferred to the web 5 becomes.

The rubber blankets 12, 62, 112, 162 are through openings on the operator side of the Frame of the printing press 1 with the aid of compressed air, each through openings in the blanket cylinders 10, 60, 119, 160 is supplied axially removable. On Compressor 80 guides the blanket cylinders 12, 62, 112, 162 through a feed line 90 air closed. There are preferably no valves or separators in the feed line 90 is provided so that all four cylinders 10, 60, 110, 160 are supplied with air at the same time becomes.

Fig. 2 shows one of the blanket cylinders 10 with a plurality of openings in the form of air holes or nozzles 14 on the operator side of the blanket cylinder 10. If the blanket 12 is removed from or applied to the cylinder, are the Holes 14 are normally covered unless the blanket is completely removed. To remove and apply the rubber blanket 12 from or to the Supporting blanket cylinders 10 is an additional series of flow-limited openings in the form of holes or nozzles 16 are provided. The Holes 16 are axial between the first row of operator side holes 14 and the Drive side of the cylinder arranged. The additional holes 16 include at least a hole that is located closer to the drive side of the cylinder than to the operator side is.

As shown in one embodiment in FIGS. 4 a and 4 b, the flow-restricted holes 16 have a supply line or an inlet 70 with a flow limiter 78 in the supply line 70. The flow restrictor 78 can be part of the cylinder 10 or be removable from it. The flow limiter 78 in this embodiment comprises a plurality of opposing fins 76, the tips of which form a free or open channel d, ie a free flow channel, if there are no eddies. When a rubber blanket sleeve 12 is placed over the hole 16, as shown in Fig. 4a, a back pressure is provided by pressure build-up, so that a uniform air flow through the flow restrictor 78 is obtained, the pressure on the inside of the blanket 12 exerts and when expanding the Blanket 12 helps.

If the rubber blanket 12 is pulled in the operator-side direction 2 so that it can be removed, the holes 16 are not covered, as shown in Fig. 4b. There no back pressure blocks the flow of air through flow restrictor 78, the Elevations 76 as the speed of air flow increases, vortices that the block most of the air flow through flow restrictor 78, and thus Air pressure created by compressor 80 (FIG. 1) in line 90 receive.

All holes that are not located near the operator-side holes can Have flow limiter 78. The operator-side holes 14 can also Have flow restrictors or not.

3 shows a blanket cylinder 10 for a plurality of sleeve-shaped blankets 12, 212, 312, which are shown schematically above the cylinder 10. To the Applying blankets 12, 212, 312 to the cylinder 10 slides the blanket 312 over the operator side holes 14, then over a second row of holes 114 and comes to a standstill so that the operator-side end of the rubber blanket 312 over one third row of holes 214 is arranged. The rubber blanket 212 is arranged so that it is next to the rubber blanket 312, the operator end of the Blanket 212 lies over the second row of holes 114. The rubber blanket 12 lies on the operator end above the holes 14. All holes in this Embodiment can have flow restrictors. Additional holes with Flow restrictors could also be between rows 14, 114, 214 of holes be arranged.

5 to 9 show further embodiments of a flow limiter 60, which in the Space 50 between the outer surface of cylinder 10 and a second inner one Layer 65 of the cylinder 10 is arranged.

The flow restrictor 60 in the embodiment of FIG. 5 includes before Exit hole 16 flow obstructing objects 63 in an air or fluid supply 70.

Fig. 6 shows another embodiment with a textile flow restrictor 60, e.g. made of fleece or a textile or fibrous material.

7a and 7b show a top view and a side view of a labyrinth-shaped Flow limiter 60 in room 50. During the unimpeded fluid flow without Back pressure, which is generated by the sleeve, can arise in the corners of the vortex Form labyrinths.

Figures 8a and 8b show a top view and a side view of another labyrinth-shaped flow limiter 60, which is arranged in space 50.

9 shows a sandwich-shaped flow restrictor 60 in space 50, wherein alternately holes are arranged on the different sides of the sandwich layers.

10 shows a further embodiment of the printing cylinder 10 according to the invention, a flow limiter 78 in the form of a with a ball 400 in the pressure cylinder Ball valve provided. The ball 400 is within the Flow limiter 78 is movably arranged so that it depends on the Position of a pressure sleeve 12 throttle the fluid flow through the flow restrictor 78 can. The fluid is supplied via a supply line or an inlet 70 Flow limiter 78 is supplied and flows around the ball 400.

The pressure sleeve 12 is in a position such that the opening 60 through the Pressure sleeve 12 is covered, so it occurs in the space between the pressure sleeve 12 and the pressure cylinder 10 to build up a compressed air cushion and thus one Pressure increase, so that the ball 400, which is to be regarded as a valve element, at least is moved slightly into the interior of the compressed air limiter 78. As a result, can the fluid flow, e.g. an air stream, wash around the ball 400 and out of the opening 16 escape. Instead, the pressure sleeve 12 is moved into a position so that it No longer covers opening 16, the valve element 400 is only from the inlet side 70 pressurized with a fluid pressure so that it is in relation to the pressure cylinder 10 moved outwards and at least largely closes the opening 16.

A channel 402 can be provided in the valve element or in the ball 400 form, through which even in the closed state of the valve element Fluid flow reaches the outside area, which means that when it covers the opening 16 a pressure sleeve 12 in turn for building an air cushion and thereby for Pushing down the ball 400 comes.

The valve element 400 can deviate from the spherical shape shown in FIG. 10 also take any other form that allows the valve element to move within the flow restrictor 78, e.g. also an elongated shape or conical shape conceivable.

Furthermore, the additional supply channel 42 can take place in the valve element 400 also formed as a bypass to the valve element 400 in the flow limiter 78 his.

The flow restrictors can form a part with the cylinder or can be used as Insertion elements can be formed in the existing holes in a cylinder be pressed or screwed. This makes it easier to manufacture new ones Cylinders and also easier conversion or retrofitting of existing cylinders. The Flow restrictors can be made of plastic or a metal. flow of another form, e.g. slats 76 of square or triangular design in FIG. 4, can also be used.

While air is a preferred fluid to aid in sleeve removal, other fluids could be used.

While the present invention is based on the preferred embodiment Use described with a blanket cylinder, but could also be used with others Types of sleeve-shaped printing blankets, e.g. Flexo sleeves or printing form sleeves for offset printing can be used.

The present invention has particular advantages when used in a printing press with a variety of pressure cylinders powered by a single pressure source be used. The pressure from the pressure source can thus be on a sufficient level is maintained even if different blankets or other sleeves are removed. Even if several sleeves from different cylinders, e.g. even cylinders of different printing units are removed, there is no uncontrolled outflow of fluid.

List of reference numbers

1

press

2

movement direction

5

train

8th

plate cylinder

10

Blanket cylinder

12

first sleeve-shaped rubber blanket

14

Air holes or nozzles / openings

16

Air holes or nozzles / openings

50

room

58

plate cylinder

59

Blanket cylinder

60

flow

62

second sleeve-shaped rubber blanket

63

flow obstructing objects

65

second inner layer

70

Supply line / inlet

76

slats

78

flow

80

compressor

90

Feed line / feed

110

Blanket cylinder

114

second row of holes / openings

112

third sleeve-shaped rubber blanket

160

Blanket cylinder

162

fourth sleeve-shaped rubber blanket

212

sleeve-shaped printing blanket

214

third row of holes / openings

312

sleeve-shaped printing blanket

400

Ball / valve element

402

channel

d

Opening / free channel

Claims (16)

Printing cylinder, in particular blanket cylinder (10), for receiving an axially positionable and / or axially displaceable printing sleeve, in particular blanket sleeve (12), with a cylinder body having an outer surface, the outer surface comprising at least one opening (14), and with a feed (90), in particular a supply line (70), for supplying fluid, in particular air, to the at least one opening (14),
characterized in that the feed (70, 90) has at least one flow limiter (60, 78) which changes the fluid flow depending on the axial position of the pressure sleeve (12). Printing cylinder according to claim 1,
characterized in that the flow limiter (60, 78) generates vortices when the at least one opening (14) is at least partially not covered by the pressure sleeve (12). Printing cylinder according to claim 1 or 2,
characterized in that the flow limiter (60, 78) has a plurality of fins (76). Printing cylinder according to one of claims 1 to 3,
characterized in that the ends of opposing fins (76) are spaced such that they form a free channel (d) for the fluid flow. Printing cylinder according to claim 1 or 2,
characterized in that the flow restrictor (60, 78) comprises flow-obstructing objects and / or textile material and / or fiber material. Printing cylinder according to claim 1,
characterized in that the flow limiter (60, 78) comprises a valve which is open or at least largely closed depending on the axial position of the pressure sleeve (12). Printing cylinder according to one of the preceding claims,
characterized in that the at least one opening comprises a plurality of openings (14) which are circumferentially offset on the outer surface of the cylinder body. Printing cylinder according to claim 7,
characterized in that the plurality of openings (14) is associated with a pressure sleeve (12). Printing cylinder according to one of the preceding claims,
characterized in that the at least one opening comprises a plurality of openings (14, 16, 114, 214) which are arranged offset in the axial direction on the outer surface of the cylinder body. Printing cylinder according to claim 9,
characterized in that the plurality of openings (14, 16, 114, 214) is assigned to different pressure sleeves (12, 212, 312). Printing cylinder according to one of the preceding claims,
characterized in that at least one of the plurality of openings (14) is assigned to a first pressure sleeve (12) and that at least one further of the plurality of openings (114) is assigned to a further pressure sleeve (212), the pressure sleeves being axially offset on the pressure cylinder are positionable. Printing cylinder according to one of the preceding claims,
characterized in that the at least one opening (16) is arranged in the area of the drive-side end section of the printing cylinder and in that further openings are provided in the area of the operator-side end section of the printing cylinder. Printing machine, in particular offset printing machine or web-fed rotary offset printing machine, with a compressed air supply (80, 90),
marked by
a first impression cylinder (10, 59) according to one of the preceding claims and at least one second impression cylinder (110, 160) according to one of the preceding claims. Method for axially positioning and / or moving a printing sleeve, in particular a rubber blanket sleeve (12), on a printing cylinder, in particular a rubber blanket cylinder (10), the printing cylinder comprising a cylinder body having an outer surface with at least one opening (14), and wherein a feed ( 90), in particular a supply line (70) for supplying fluid, in particular air, to which at least one opening (14) is provided,
marked by: Providing fluid pressure on an inside of the pressure sleeve (12) by means of the at least one opening (14); Axial displacement or positioning of the pressure sleeve (12); and Automatic limitation of the flow through the at least one opening (14) by means of a flow limiter (60, 78) which changes the fluid flow depending on the axial position of the pressure sleeve (12). Method according to claim 12,
characterized in that the step of automatically limiting the flow comprises forming fluid vortices. Method according to claim 12,
characterized in that the step of automatically limiting the flow comprises at least largely closing a valve.

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