The present invention relates to a plant for cleaning inking and printing rollers and of the type specified in the introduction of claim 1.

DE 9106454U1 describes an apparatus for cleaning items such as inking rollers and other printing unit parts for printing machines by using a water-based cleaning liquid, the apparatus including a cabinet configured as a vessel with a cover and a mesh-formed support face for items to be cleaned, a number of nozzles adapted to spray the items and a pump arranged to supply the nozzles with a cleaning liquid which is recirculated by sucking from the bottom of the cabinet, at which a filter unit with a disposable filter is inserted between a suction branch from the vessel and the nozzles.

There is described an efficient cleaning apparatus which can operate with a relatively small amount of cheap water-based cleaning liquid. This is possible because the cleaning liquid is recirculated, i.e. pumped up from the bottom of the vessel and cleaned efficiently by passing the disposable filter which can be discarded relatively cheaply according to current environmental requirements.

In addition to this prior art cleaning apparatus which is particularly suited for cleaning small inking rollers and other relatively small printing unit parts, larger special cleaning apparatuses are known which are adapted for cleaning larger inking rollers where the latter are arranged rotating and vertically upright during the cleaning process.

The development within the printing industry has gone in the direction that the present inking and printing rollers with time have become relatively large and heavy, causing a serious work environmental problem in connection with transport of large and heavy inking and printing rollers between cleaning apparatuses and printing machines.

On this background, it is the object of the invention to provide an improved plant for cleaning inking an printing rollers which by simple technical means is capable of counteracting the work environment problems associated with lifting and transporting relatively large and heavy inking and printing rollers between a printing unit the and cleaning apparatus, and not the least handling of such inking and printing rollers in connection with insertion into and extraction out of the cleaning apparatus.

The plant according to the invention is characterised in that in the cleaning chamber is arranged an elevating track system for leading a trolley in and out, the trolley having one or more support bearings for inking and printing rollers which are transferred to and from the rotary bearings in the cleaning chamber by lowering and elevating, respectively, the track system and the trolley which is adapted to be led into and out of the elevating track system in the cleaning chamber via fixed track sections of transport racks which are adapted to be placed at respective sides of the cleaning chamber and to be handled by means of separate lifting equipment, e.g. a forklift truck. By simple technical means it hereby becomes possible to counteract the work environment problems associated with lifting and transporting relatively large and heavy inking and printing rollers between printing unit and cleaning apparatus, and not the least handling such heavy inking and printing rollers in connection with inserting into and extracting out of the cleaning apparatus.

The general aspect of the invention is to achieve an optimised cleaning process and hereby facilitate handling of relatively heavy inking and printing rollers in such a way that lifting of inking and printing rollers in principle only occurs at the printing unit where inking and printing rollers are transferred to and from the printing unit via the said trolley on the indicated transport racks by means of suitable lifting equipment.

In other words, this is an appreciable improvement of the working environment in that transfer of the heavy inking and printing rollers between transport rack and cleaning apparatus can be effected entirely without any lifting operations as during the entire transportation between cleaning plant and printing unit, the inking and printing rollers are supported on the indicated trolley on transport racks.

Alternatively, the inventive plant can be designed such that it includes an apparatus with several successively arranged cleaning chambers, e.g. a primary cleaning chamber in which is performed a pre-cleaning of inking and printing rollers by applying a special cleaning liquid via a system of nozzles, and a secondary cleaning chamber in which e.g. is performed a finishing treatment in the form of high-pressure flushing and drying by means of compressed air.

The plant according to the invention can be suitably designed such that the transport racks with the fixed track sections are adapted in height and in width to the elevating track system in the cleaning chamber of the apparatus such that the fixed track sections of the transport racks can be disposed opposite the elevating track system at respective sides of the plant.

With the intention of further automating the cleaning process, the plant according to the invention may advantageously be designed such that in connection with at least one primary cleaning chamber there are provided means adapted to get hold of a foremost trolley on a foremost transport rack located in front of the primary cleaning chamber and actively draw the foremost trolley with one or more inking or printing rollers into the cleaning chamber.

The plant according to the invention may suitably be designed such that the inserting means are constituted by a hydraulically, pneumatically or electrically powered mechanism with a piston with a palm mechanism adapted to interact with a projecting part of the trolley such that a foremost trolley can be drawn into the cleaning chamber.

The plant according to the invention may be designed in size such that the apparatus including cleaning chamber with associated rotary bearings, the trolley and the transport racks is provided in sizes adapted to inking and printing rollers with lengths between 300 and 3000 cm.

The invention is explained more closely in the following with reference to the drawing, on which:

Fig. 1

shows a perspective view of an embodiment of a plant according to the invention where a trolley with two inking or printing rollers is ready to be moved into a cleaning chamber of a cleaning apparatus;

Fig. 2

shows a perspective view of a plant, cf. Fig. 1, where a trolley with two inking or printing rollers are on their way into the cleaning chamber;

Fig. 3

shows a perspective view of a plant, cf. Fig. 1, where a trolley with two inking or printing rollers are on their way into the cleaning chamber simultaneously with a second trolley with two inking or printing rollers being on their way out of the cleaning chamber at the opposite side thereof;

Fig. 4

shows a perspective view of a part of a plant according to the invention where a transport rack with two inking or printing rollers are shown enlarged;

Fig. 5

shows a perspective view of a plant according to the invention where the transport system of the plant itself is shown without a cleaning chamber, for illustrating the elevating track system in the cleaning chamber;

Fig. 6

shows a perspective view of a second embodiment of a plant according to the invention where two cleaning chambers are arranged in succession; and

Fig. 7

shows a perspective view of a modified embodiment of a plant according to the invention where a transport rack is designed with drain tray and collecting container etc.

The cleaning plant 2 shown in Fig. 1 includes a cleaning apparatus 6 for cleaning inking and printing rollers 4 that during transport to and from the cleaning apparatus 6 are disposed on a trolley 14 in support bearings 16, the trolley 14 disposed on fixed track sections 18 of a transport rack 20 during the transportation.

In Fig. 2, a door 28 for a cleaning chamber 8 of the cleaning apparatus 6 has been opened by activating an opening/closing cylinder 30, and the trolley 14 with two inking and printing rollers 4 are on their way into the cleaning chamber 8.

In Fig. 3 appears that at the same time, a second trolley 14 is on its way out from the opposite side of the cleaning chamber 8 where the trolley 14 with inking and printing rollers 4 are disposed on fixed track sections 18 of a transport rack 20 at the opposite side of the cleaning apparatus 6.

In Fig. 4 appears a trolley 14 with two inking and printing rollers 4 in ready position on fixed track sections 18 of a transport rack 2; through a window in the door 28 an inking or printing roller 4 under cleaning treatment appears in cleaning chamber 28.

Fig. 5 serves to illustrate the moving system of the cleaning plant 2 according to the invention where the cleaning chamber 8 itself has been removed. At opposite sides of the apparatus 6 there are provided transport racks 20 with fixed track sections 18. A trolley 14 is placed on the elevating track system 12 which is supported by four lifting/lowering cylinders 26 (only two are shown) such that the track system 12 and trolley 14 can be moved downward so that inking and printing rollers 4 possibly placed in trolley 14 are transferred to rotary bearings 10 in the cleaning chamber 8 so that the inking and printing rollers 4 can be rotated during the cleaning process, as indicated.

Fig. 6 shows an alternative cleaning plant 3 which includes an apparatus 5 with several successively arranged cleaning chambers, e.g. a primary cleaning chamber 7 in which is performed a pre-cleaning of inking and printing rollers 4 by applying a special cleaning liquid via a system of nozzles, and a secondary cleaning chamber 9 in which e.g. is performed a finishing treatment in the form of high-pressure flushing and drying by means of compressed air.

Fig. 7 shows a modified embodiment of a cleaning plant 2 according to the invention where a larger inking or printing roller 4 is placed on a trolley 14 on transport rack 20 which includes a drain tray 23; furthermore, a collecting container 22 and a filter 24 are seen.

The plant 2 including the apparatus 6 with cleaning chamber 8 and associated rotary bearings 10, the trolley 14 and the transport frames 20 may be provided in sizes adapted to inking and printing rollers with lengths between 300 and 3000 cm.

With the intention of further automating and optimising the cleaning process, the plant according to the invention may advantageously be designed such that in connection with at least one primary cleaning chamber there are provided inserting means adapted to engage a foremost trolley on a foremost transport frame located in front of the primary cleaning chamber, and actively pull the front trolley with one or more inking or printing rollers into the cleaning chamber.

The inserting means can e.g. be constituted by a hydraulically, pneumatically or electrically powered mechanism with a piston with a palm mechanism adapted to interact with a projecting part of the trolley 14 such that a foremost trolley 14 can be drawn into the cleaning chamber 8. When the said foremost trolley 14 is drawn into the cleaning chamber 8, a trolley 14 possibly already drawn therein will automatically be pushed out of the cleaning chamber 8 or further into a possible secondary cleaning chamber 9 if the apparatus 6 includes more than one cleaning chamber 8.

The plant 2 may furthermore include an dedicated accumulation track in front of the cleaning chamber 8 of the apparatus 6 where a number of transport racks 20 can be arrayed with mutually flush track sections 18 such that a trolley 14 situated on a transport rack 20 may easily be transferred to a transport rack 20 disposed in front thereof, etc. Within the main aspect of the invention, such an accumulative track with transport racks 20 can include feeding means that are adapted for providing automatically a continuous transfer of trolleys 14 to an empty transport rack 20 disposed at the front in the accumulation track.

Finally, it is to be emphasised again that the general aspect of the invention is to facilitate handling of relatively heavy inking and printing rollers 4 in such a way that lifting of inking and printing rollers 4 in principle only occurs at the printing unit where inking and printing rollers 4 are transferred to and from the printing unit via the said trolley 14 on the indicated transport racks 20 by means of suitable lifting equipment. In other words, transfer of the heavy inking and printing rollers 4 between transport rack 20 and cleaning apparatus 6 can be effected entirely without any lifting operations as the inking and printing rollers 4 during the entire transportation between cleaning plant 2 and printing unit is supported are supported on the indicated trolley 14 on transport racks 20 which are handled by means of separate lifting equipment, e.g. a forklift truck.

2

cleaning plant

3

alternative cleaning plant (Fig. 6)

4

inking or printing roller

5

alternative cleaning apparatus (Fig. 6)

6

cleaning apparatus

7

primary cleaning chamber (Fig. 6)

8

cleaning chamber

9

secondary cleaning chamber (Fig. 6)

10

rotary bearings

12

elevating track system

14

trolley

16

support bearings

18

fixed track sections

20

transport rack

22

collecting container

23

drain tray

24

filter

26

lifting/lowering cylinder

28

doors for cleaning chamber

30

opening/closing cylinder