During web breaks and threading of paper and board is formed shredded material which must be removed from the area of the finishing device, for example, a calender or a coating device. For example, the rolls of a finishing device may also be fouled by the coating material, which penetrates through the pores in the paper during coating, and by dirt carried by the web. Until now, rolls have been washed manually and cleaned by means of a doctor blade. Manual cleaning with a sponge is cumbersome and time-consuming and also labour-intensive. Due to a high running speed and greater susceptibility to fouling than before, the need for cleaning is great as rolls are soiled rapidly. Since manual cleaning of the rolls is slow and soiling rapid, manpower is required for cleaning almost constantly. The work demands great care, because water may not drip from the sponge onto the web, and it is usually desirable to carry out the cleaning during running. Since the running speeds and widths of current machines are great, cleaning long rolls manually is extremely difficult and work safety in the area inside the frames of the finishing device is questionable.

Instead of manual washing, rolls are typically cleaned by using cleaning doctor blades. In using them, the surface of the roll is scraped clean by means of a doctor blade. Water is used to facilitate cleaning. Disadvantages of doctor blade cleaning include splashing of the water used, the wearing effect of the doctor blade on the roll, and poor functioning with high speeds exceeding 10 m/s (600 m/min). The splashing of water causes uncleanliness and, if splashed on the web, spoils the paper being treated. Due to disalignment of the roll being cleaned and the doctor blade, the load directed

by the doctor blade on the roll is uneven, which wears the blade and the roll.

Since the requirements for straightness made on the roll are extremely strict, even the slightest wear in the roll will result in a fall in the quality of paper, and thus in a change of roll. Changing the expensive roll and the stoppages resulting from it increase operating costs.

Accordingly, it is an aim of the present invention to provide a new type of cleaning apparatus, by means of which the finishing device can be cleaned while running, avoiding at the same time movement in the area between the frames of the finishing device.

To achieve this aim, the cleaning apparatus according to the invention is characterised in that the cleaning apparatus comprises first cleaning means and/or second cleaning means, which first and second cleaning means are remote-controlled and arranged to direct a cleaning medium jet at desired points of the finishing device. Some preferred embodiments of the cleaning apparatus relating to the invention are disclosed in dependent claims 2 to 5.

The invention is described in greater detail in the following, with reference to the accompanying drawings, in which: Figure 1 shows diagrammatically the cleaning apparatus according to the invention when fitted in a calender, and Figures 2-4 show diagrammatically details of the cleaning means comprised in the apparatus shown in Figure 1 on an enlarged scale.

In Figure 1, by reference numeral 10 is marked a calender, between the frame parts 11 and 12 of which are rolls 13 and 14 which form a calender nip. For example, during web breaks and threading of the material to be calendered paper shreds are formed, which must be removed from the

calender area. In the embodiment shown in Figure 1, the cleaning apparatus comprises five different types of cleaning devices which can be used together or separately according to need. These cleaning devices are remote- controlled, which means that moving in the area between the frames can be avoided. By reference numeral 1 is marked a conveyor mat by means of which fallen shreds can be conveyed directly to a pulper. The conveyor mat consists of a fabric (e. g. an old machine felt laid over a frame, the fabric being wound by means of an electric motor and the fabric being supported from underneath by means of plates, which means that walking on it is possible when the cleaning device is switched off. By reference numeral 2 is marked a blast-cleaning device, which is movable in the longitudinal direction of the roll and described in greater detail in connection with Figure 2. By reference numeral 3 is marked an embodiment of a mechanically controlled edge zone blast-cleaning device, which is described in greater detail in connection with Figure 3, and reference numeral 4 designates a second embodiment of a mechanically controlled edge zone blast-cleaning device, which is described in greater detail in connection with Figure 4. By reference numeral 5 is marked a fixedly mounted blast head, which can be directed at a predetermined location.

Figure 2 shows in greater detail a preferred embodiment of an electrically remote-controlled blast-cleaning device, which comprises a transfer car 22 movable by a cable wire or by means of an electric motor installed directly in the transfer car, on wheels 25 along a transfer rail 23, in the longitudinal direction of the roll 13. To the transfer car 22 is connected a telescopic arm 21, preferably in a turning manner, through which a cleaning jet 20, for example an air jet or a liquid gas jet, can be directed at desired points on the surface of the roll 13 to be cleaned. Reference numeral 24 denotes a hose and cable reel, by means of which the cleaning medium hoses and electric cables can be maintained in order.

Figure 3 shows in greater detail the blast-cleaning device 3 shown in Figure 1 for the edge zone adjacent to the frame part 11 of the roll 13, the said device being used mechanically by means of a swinging arm 31, by means of which the blast head 32, for example an air jet, can be directed into the desired position via the vertical swivelling axis 33 and the sideways swivelling axis 34. Reference numeral 30 denotes a cleaning medium jet. The swivelling axis 33 is fixed to the frame part 11 through bearing means 45.

By reference numeral 5 is marked a fixedly mounted blast head, from which a cleaning medium jet 50 can be directed at a predetermined location. There may be a fixed blast head 5 in both edge zones of the roll, or it may also be left out altogether.

Figure 4 shows in greater detail the cleaning apparatus 4 for the edge zone adjacent to the frame part 12 of the roll 13 shown in Figure 1. The apparatus comprises a turning handle 4S, by means of which the blast head 42 can be controlled from outside the frame for directing the cleaning medium coming from the blasting arm 48, for example an air jet 40, at the desired point in the edge zone of the roll. To the turning handle 41 is connected a belt or chain 43 and a cable wire 44 for performing the turning movements. The chain 43 is connected to a chain wheel 46 on the turning handle 41a and to a chain wheel 47 on the blast head 42. The movement of the turning handle 41a rotates the blast head 42 via the chain 43 about its longitudinal axis in the bearing means 50, and the blasting arm 48 turns in the vertical part at the same time. The turning rod 41a is mounted in bearings on the frame part 12 by bearing means 45. The wire cable 44 is connected through supporting rolls 49 to the turning handle 41 and blasting arm 48 to turn the blasting arm 48 sideways with respect to the blast head 42.

In the cleaning apparatus according to the present invention, the cleaning medium used is preferably compressed air, but it may also be a composition

of liquid and gas, for example aqueous steam. The cleaning medium may also contain cleaning agent and/or degreasing agent, for example, for dissolving and removing the coating agent from the surface of the backing roll of the coating device.

The edge zone cleaning devices of the roll may be identical, for example, there being a cleaning device 3 or 4 in both edge zones, or different, as in the embodiment shown in Figure 1.

The cleaning apparatus according to the invention can also be used for cooling the rolls during running, for example, for cooling the end zones of polymer-surface rolls. Cooling may take place in connection with the cleaning of the rolls or, if necessary, as a separate procedure.

Above, the invention is described in connection with the cleaning of the calender roll, but objects of cleaning may also include other parts of the finishing device, such as different beam constructions, for example, the doctor blade frame, various measuring beams, coating machine nozzle beams, and other constructions.