The calenders of a paper machine have to be serviced and cleaned also during operation. It is important for the use that the machine can be cleaned right after the web feeding. This requires that work has to be done in the area between calenders during operation, where it is dangerous to work. The biggest risk of accident is in a situation in which the person performing the cleaning is between the calenders when the roller coating breaks. In this case pieces of the broken roller coating fly with a great velocity to the working area.

Cleaning the calenders has been done so that the person performing the cleaning has entered with the cleaning equipment the area between the calenders and performed the necessary cleaning steps. For securing the safety, the person has used normal protective gear required by the circumstances and known in itself, such as protective glasses, and hearing protectors.

With the present methods, it is usually possible to clean the calenders in an appropriate way during operation. However, the safety risks for the person performing the cleaning are high. The normal protective gear used in industry does not offer very much protection if the roller coating tears. In fact, it usually only makes working more difficult and weakens the observation. Naturally, it is also dangerous to work between the rotating rollers at other times besides the moment the roller coating tears. For example, a tool, sleeve of a jacket, or some other object or piece of clothing suitably hitting them may easily get caught between the rotating rollers. If this object is attached to the person or his clothes, this may result in a serious accident.

Description of the invention It is the object of the invention to provide a safety device with which the above said safety risks are avoided. Further, it is the object of the invention to bring forward a safety device, which restricts work as little as possible and the use of which makes it

possible to perform the necessary cleaning, service and maintenance work during operation as well, as easily and as fast as possible.

The object of the invention is achieved with a safety device which is characterised in what is disclosed in the claims.

The safety device of the invention is a room movable between the structures of a paper machine and fitted for one person, and formed of one or several walls. At least one wall contains one or several openings for performing service and maintenance measures to the machine. Because of the box, for example, the cleaning, service and maintenance steps to be performed on the calenders of the paper machine can be done safely also, for example, when the coating of the calender roller breaks. Due to one or several openings, repairs can be made from the interior of the room in a simple and easy manner, using tools that are known in themselves.

In an advantageous embodiment of the invention, the safety device is movably attached to rails between the structures of the paper machine. A fastening carried out in this way operates in an appropriate way, it is simple and economical.

In a second advantageous embodiment of the invention, one or several openings have been arranged so as to be movable in relation to the wall. Thus, the targets in different places in the paper machine are accessible easily and fast, preferably through the same opening.

In a third advantageous embodiment of the invention, the safety device includes at least one wall or wall part, which can be opened as a passage. Due to the wall or wall part to be opened, it is possible to leave the room in an easy and fast way both in an emergency and in a case in which the room has been transferred to the place of exit. In this case, the safety device preferably includes a door, which is placed to the side wall of the safety device, seen from the direction of the paper machine. Both side walls may contain a door. The position of the exit ways then comes to an advantageous place in relation to the paper machine so that it is simple and safe to leave the box.

In a fourth advantageous embodiment of the invention, the paper machine has at least one gate placed by the safety device, which can be opened and locked fast by a locking device to prevent access to any other place besides the safety device. In this way access is efficiently prevented to a dangerous area as the safety device is in use and transferred into the interior of the paper machine. A gate may be provided on

both sides of the paper machine. In this way it is possible to enter the safety device from both sides of the paper machine so that efficiency in work increases and the convenience to use the safety device improves.

In a fifth advantageous embodiment of the invention, the room is formed of a rectangular tubular frame, to which side walls, end walls and roof are attached. Such a structure is durable and safe, and the number and place of the working openings in the walls can easily be altered.

The invention is next described in more detail, referring to the enclosed drawings, in which Fig. 1 is a side view of a safety device according to the invention, and Fig. 2 is a front view of the safety device of Fig. 1.

The safety device of Figs. 1 and 2 has a room 1 fitted for one person and comprising a tubular frame 2 and a side walls 3 and 4 attached to it, a front wall 5, a back wall 6, and a roof 7. In its front wall, the safety device further comprises an opening 8, movable in the vertical direction, fixed openings 9 and 10 in the side walls, rails 11 fastened to the structures of the paper machine, and gates 12 which can be locked at the place of the room on both sides of a paper machine.

The room 1 has been manufactured of the tubular frame 2, to which the side walls 3 and 4, the front wall 5, the back wall 6 and the roof 7 are fastened. The room is fastened on rolls, movably supported on two transverse rails 11 in relation to the paper machine so that the room can be moved between the structures, such as the rollers of the paper machine, from one side of the machine to the other.

In the front wall 5 of the room 1, a wall part provided with an opening is movably fastened in the vertical direction of the box on guides installed in the wall so that the opening 8 in the wall part is movable in the vertical direction of the room. The side walls 3 and 4 are fastened to the frame structure between the front wall and the side walls by hinges. The edge of the side walls facing the back wall includes locking bolts. Thus, the side walls of the room can be opened and locked fast.

The side walls 3 and 4 may also operate as emergency exit doors even when the room 1 is in the working position. In this case the opening of the doors may be combined with the operation of the machine so that one or several dangerous

functions are interrupted as the door opens. Such functions may be, for example, the pressing of the nip of the calender or the cutting of the web.

The fixed opening 9 is in the upper part of the side wall 4 and the fixed opening 10 is near the lower part. The locked gates 12 manufactured of tube are installed at the place of the room on the sides of the paper machine. The gates are attached to the structures on the sides or to the fixed fences installed in these, when required, from the other edge by hinges. Electric locks are attached to the other edge of the gates, with which the gates can be locked or they lock automatically as the safety device is moved away from the vicinity of the gate.

Here the room 1 is placed between the drying section 13 and the calender 14 of the paper machine. For example, the roller 15 of the calender can be cleaned from the box by blowing air onto it with the help of the air tube 15. For example, a possibly breaking coating of a soft calender does not harm the employer in the box.

When using the safety device, the person performing the cleaning, service or maintenance goes into the room, bringing the necessary tools with him. In this case, the room has been transferred to either side of the paper machine. The gate is then closed, and it locks automatically, as the room is transferred away from the side of the gate. The room is further transferred to a suitable place, from which the desired maintenance measure can be performed. In the application of Figs. 1 and 2, the transfer of the room is performed manually, but in some other application, the room may, for example, include an electrically operated transfer apparatus, with the help of which it can be moved, controlled by the switches installed inside the box. When the room is at a suitable place, the necessary measures are performed through the openings in the walls. The room protects the employer from objects possibly coming off from the paper machine, such as pieces of roller coating. If there are several targets within the operating range of the room, or the target is big, the room may at times be moved when the need arises so that the measure in question can be done in an appropriate way through one of the openings in the room. After all the desired measures have been done, the room is transferred back to the gate entrance on the side of the paper machine so that the gate with the electric lock opens and it is possible to leave the room with the tools by opening the side wall.

The structure, materials and operation principle of the safety device according to the invention may vary. The room may be a piece formed of one piece as a box. In this case, the room does not necessarily include a separate frame structure, but the different parts are fastened directly to the walls of the room by different fastening

elements. The shape and size of the room may vary. However, it has to be at least so big that at least one grown-up person can work in the room. For tight places the room may be shaped so that it utilises the available space as well as possible. The walls of the room may also include more openings than in the application of Figs. 1 and 2. The openings may be movable, open, or they may be closed by a lid in different ways. Also the position of the openings may vary. There may be openings also in the roof and the back wall. The room may include doors of the size of the wall, as in the application presented above, or the doors may be smaller than the wall. There may be one door or several doors, however, most preferably, two, one on each side of the room, as in the application of Figs. 1 and 2. The doors may be opened in different ways, e. g. they may be turned open or pushed to the side. The room may also include a seat so that the height may be decreased correspondingly.

The moving fastening of the room can be realised in many different ways. The room may be fastened on rails by wheels, rolls or guides belonging to either end wall, the rails being directed also to other directions than the transverse direction in relation to the paper machine. Alternatively, the room can move on rails fastened to the floor or on wheels attached to the lower part of the room, guided merely by a groove formed in the floor or by a pin in the room. The room can be movably attached also on cables or using a mechanism enabling the suitable movement. The most suitable way of fastening can be chosen according to the structure of the paper machine and the places to be repaired in it and the moving space available. The gates to be fastened to the structures of the paper machine preventing access elsewhere besides the room can also be realised in many different ways. The number, size and direction of the gates may vary. The gates may be fastened on hinges or to be opened otherwise, and to be locked fast in many different ways. Besides electric locks, the locks may also be mechanical locks or, for example, merely simple bolts or latches.

The safety device of the invention may be used in different kinds of paper machines for maintenance measures to be performed in the area between the calenders.

However, it may also be used in other similarly dangerous places. The structure of the room, the direction of movement, the number and type of openings as well as the direction of the opened walls or doors can then be chosen appropriately in a way determined by the location and direction of the targets of the maintenance measures.