FI120460B - Sheet forming machine equipped with an arrangement for mounting or replacing a blade and method and apparatus for mounting or replacing a blade in a sheet forming machine - Google Patents

Description

MACHINERY WITH A SCRAPER

FOR INSTALLATION OR REPLACEMENT, AND METHOD AND DEVICE FOR SCRAPER

FOR INSTALLING OR REPLACING THE BLADE IN A FOLDING MACHINE

The invention relates to a web-making machine provided with an arrangement for mounting or replacing a doctor blade, in which the frame structure of the web-making machine is supported by a blade holder for the doctor blade. The invention also relates to a method and apparatus for installing or replacing a doctor blade in a web-forming machine.

The web making machine uses scrapers in several positions which require replacing the scraper blades. The web-making machine is a paper, board, or puck machine or web-finishing machine. When replacing a single scraper blade, the first worn scraper blade is removed from the blade holder and a new one is installed in the blade holder. The scraper is almost invariably placed in the vicinity of a rotating machine member such as a roller. In the scraper operating position, the scraper blade contacts the surface of the roll, but in the case of replacement, the scraper blade is generally off the roll surface. As is known, when removing a doctor blade, the machine element is first stopped, after which the installer goes to the blade holder and pulls the doctor blade out of the blade holder in the transverse direction of the web making machine. Then insert the new scraper blade into the blade holder. 25 After replacement, the web making machine is started and the doctor blade is loaded against the surface.

The current web making machine is already over ten meters wide. At this end, the machine member 30 supported at each end is massive and its end portions with bearings take up a lot of space. The bearings are usually supported on the web structure of the web making machine. In this case, the installer must go inside the frame to reach the blade holder. This practice requires at least two installers, one inside the frame and 35 outside the other to support a long and flexible scraper blade. To ensure occupational safety, the machine element must first be stopped and then restarted, which will take a lot of time, even if the scraper blade itself is changed quickly. The problem is further exacerbated when the machine body itself or a nearby component is hot after the production process. In this case, after the machine element has been stopped, it is necessary to wait for cooling first, and after changing the doctor blade, it is necessary to wait for the heating to start before the production begins. Thus, the total exchange time is several tens of minutes, even hours. In addition, several machine members and their scrapers are often very close together, leaving little space near the blade holder. In some of the 10 positions, even removable auxiliary platforms have had to be used on which the installer had to crawl to access the cutter holder. This is extremely dubious for occupational safety, especially when the blade holder is high when viewed from the machine level. For example, the top scraper on the current calender is more than five meters 15 feet from the plane. In this case, changing the scraper blade also carries the risk of falling, especially when using temporary auxiliary levels.

It is an object of the invention to provide a web-making machine 20 provided with an arrangement for mounting or replacing a doctor blade, which is easier to use but more versatile than before. It is also an object of the invention to provide a new method for installing or replacing a doctor blade in a web-making machine, whereby changing the doctor blade 25 is faster and safer. It is a further object of the invention to provide a new device for mounting or replacing a doctor blade in a web making machine which can be safely and versatile applied in connection with various web making machines. The web forming machine 30 of the present invention is characterized in that the means include a manual tool for mounting and replacing the doctor blade, which at one end includes gripping means for engaging a portion of the doctor blade extending outside the blade holder and actuating means Similarly, the method according to the invention is characterized in that, for mounting and replacing the doctor blade, the doctor blade is moved by a hand-operated tool from the opposite side of the blade holder to the frame structure by engaging the doctor blade portion extending outside the blade holder the use of tools. Further, the device according to the invention is characterized in that the device is a hand-held tool comprising gripping means for engaging a scraper blade portion extending beyond the blade holder and actuating means for actuating the gripping means at the other end and extending from the blade holder during installation and replacement. on the opposite side of the blade holder from the frame structure. The web making machine provided with the arrangement 15 according to the invention employs a tool for moving the doctor blade from outside the frame structure. In this case, it is unnecessary to get between the frame structure and the machine member, while it is unnecessary to wait for hot surfaces to cool down, which increases safety at work, speeds up blade change and shortens production downtime. Auxiliary devices for supporting and guiding the scraper blade can be combined with the tool, allowing even one person to install or replace the scraper blade. The tool and accessories can be used with different blade holders. In addition, the scraper blade can be replaced with up to 25 machine members rotating. Preferably, the tool is part of a device that can be used to install and replace scraper blades of known webmaking machines.

The invention will now be described in detail with reference to the accompanying drawings, in which:

Fig. 1a shows a part of the calender of a web making machine according to the invention, viewed from the machine direction, Fig. Ib shows a part of the view from the operating side,

Fig. 2a shows a partial magnification of the schematic position of Fig. Ib, 4

Figure 2b shows a partial magnification of Figure 1a,

Figure 3a is a side view of a hand tool according to the invention,

Fig. 3b is a top view of Fig. 3a,

Fig. 4a shows a top view of a guide structure according to the invention,

Fig. 4b is a cross-sectional view of the guide structure of Fig. 4a;

Figure 5b is a side view of the fastening engagement of Figure 5a,

Figure 5c is a plan view of the fastening stop of Figure 5a,

Fig. 6 shows an arrangement according to the invention fitted in the frame structure of a web forming machine.

Figure 1a shows a portion of a calender in a web making machine provided with an arrangement for mounting or replacing a doctor blade. In Fig. 1a the view is in the machine direction 20, while in Fig. Ib the calender is viewed from the operating side. The calender consists of a plurality of overlapping rolls 10 between which are formed a plurality of fish knife nipples. The rolls 10 forming the roller 11 are supported at each end by the frame structure 12 of the web making machine. Especially in the fish blade, at least a part of the rolls 25 10 are arranged to be movable by levers 13 with loading members. In addition, the calender may be a direct extension of a web-making machine, so-called on-line calender. On the other hand, the calender may be part of a separate finishing line 30, whereby the web rolled on a web making machine is unwound prior to coating and calendering. This is the so-called off-line calendar.

Calender rolls, as with many other roll forming machine 35 rolls, generally have a scraper. The scraper is used to keep the roll surface clean and, in some applications, further 5 strips are removed from the roll surface. The scraper 14 has a blade holder 16 for the doctor blade 15, which is supported on the frame structure 12 of the web making machine (Fig. 2a). Correspondingly, the blade holder 16 is usually supported on a scraper bar 19, which is supported at each end 5 by the frame structure. Only one scraper 14 is shown in Fig. Ib, the arrangement of which is to be fitted with a check mark. In other words, all seven rolls 10 have both a scraper and an arrangement for changing the scraper blade. According to the invention, the arrangement comprises a hand tool 17 for mounting or replacing the doctor blade 15, which extends from the blade holder 16 to the opposite side of the blade holder 16 to the frame structure 12. This allows the doctor blade to be safely handled without having to enter between the frame structure 12 and the machine elements 21. This is especially important in the case of the calender, which is an application example, since there are numerous machine members and scrapers and they are also close to each other. In this case all treatment levels must be clearly outside the frame structure. In addition, the rolls are hot during production and there may be, for example, hot steam boxes between the rolls.

20 In practice, the doctor blade is mounted or replaced in the blade holder by moving the doctor blade in its longitudinal direction. In other words, the doctor blade is moved across the web making machine. The trailing edge of the plate-like doctor blade generally has pins or other protrusions that prevent the doctor blade from leaving the knife holder knob but allow the doctor blade to be moved longitudinally. According to the invention, for installing or replacing the doctor blade, the doctor blade is moved by a hand-operated tool from the opposite side of the blade holder to the frame structure. This provides good occupational safety and an ergonomically advantageous working position for the installer. 1a and 2b, the treatment bridge 18 is shown in principle in broken lines. The distance s from the blade holder 16 to the treatment bridge 18 is shown in Figure 1a. In this embodiment, such a distance is nearly two meters, so with only 35 hands it would be impossible to extend from the treatment bridge 18 to the doctor blade 15. According to the invention, the tool has a reach of at least 1000 mm.

6

Figure 2a shows a part of the roll 10 and the scraper bar 19 on which the blade holder 16 with its scraper blade 15 is supported. Here, the scraper bar 19 is shown in the operating position where the scraper blade 15 contacts the surface of the roll 10. Figure 2a also shows an arrangement according to the invention 5, the structure of which will be described in more detail later. Figure 2b shows a situation in which the doctor blade 15 in the blade holder 16 is being removed. Here, the scraper bar 19 is already turned to the blade change position. As shown in Figure 2b, the tool 17 easily and safely extends from the treatment bridge 18 10 to the scraper blade 15. Generally, when installing the scraper blade, at least a portion of the scraper blade from the frame structure to the blade holder is moved by the tool. On the other hand, when replacing the doctor blade, at least a part of the doctor blade from the blade holder to the frame structure is moved by a tool. In practice, just starting the uninstallation and completing the installation are the most difficult points where the tool has significant benefits.

Thanks to the tool, when installing and replacing the doctor blade, the doctor blade can be moved on one and the same side by 20 frame structures. This avoids entering the frame structure, which increases occupational safety. Depending on the application, the doctor blade is moved from the treatment or operating side of the web making machine. With just one tool, the scraper blade can be threaded into the blade holder from the treatment bridge or other level. However, with the long 25 tools, aligning the scraper blade can be difficult. Thus, the method utilizes a guide structure 20 to guide the doctor blade 15 to or away from the blade holder 16 (Figure 2b). In this case, when installing, the scraper blade is simply first threaded into the guide structure and then inserted into the blade holder. The remainder is then moved by a tool according to the invention. Similarly, when removing the doctor blade, the tool first pulls the doctor blade into the guide structure and then until the doctor blade is exposed at one end of the guide structure. The remainder of the scraper-35 can then be pulled by hand. In practice, thanks to the tool and the guide structure, even one person can change the scraper blade quickly 7 and safely. To allow easy replacement, the guide structure is supported in the frame structure as an extension of the cutter holder to a position corresponding to the position of the cutter holder arranged in the cutter position. Thus, with the blade holder in the blade change position 5, the doctor blade can be removed from the blade holder or mounted on the blade holder by simply pulling or pushing.

The conductor structure is preferably removably secured to the frame structure. In this case, the conductor structure can be removed during production, thereby avoiding breakage and contamination of the conductor structure. On the other hand, there can only be space for the guide structure when the blade holder is in the blade change position. Removability can also be utilized in other ways. According to the invention, the same tool and guide structure are used to install or replace more than one scraper blade. In this case, by changing the position of the guide structure, the scraper blades of the different positions can be changed. The strip making machine uses different scraper blades, so that the guide structure is preferably adapted to run on different scraper blades. On the other hand, the guide structure can be designed for a particular type of doctor blade 20 and position, whereby, for example, the calender has one movable guide structure and the dryer part has another. In addition, more than one conductor structure may be used simultaneously if sufficient persons are present. In any case, only one person is needed to replace one scraper blade.

Thanks to the tool and the guide structure, the doctor blade can be replaced without going near a rotating machine member such as a roller. In addition, the end of the guide structure is very close to the blade holder, whereby the free length of the scraper-30 blade is short. In other words, the scraper blade is constantly under control. In this case, the scraper blade can be changed while the machine member belonging to the web-making machine and in the vicinity of the blade holder rotates. It is also unnecessary to cool the hot roller, which only takes a few 35 minutes to replace the scraper blade. By the way the production process otherwise allows, the doctor blade 8 can be changed even during production without compromising work safety.

Figures 3a and 3b show a hand tool 5 according to the invention for moving a doctor blade. The tool 17 includes gripping means 22 for engaging a portion of the doctor blade 15 extending beyond the blade holder. The doctor blade can then be gripped while it is in the blade holder or guide structure. Here, the gripping members 22 consist of a stopper 24 fixed to the tubular body 23 and a clamping jaw 25 movable therewith. The clamping jaw 25 is actuated via a rod 26 or wire by a handle 27. The stopper and clamping jaw are equally wide and adjustable. In this case, the relative position of the handle and the gripping end 15 can be adjusted as desired. The abutment and the clamping jaw extend clearly beyond the tubular body, whereby the doctor blade can be grasped on either side as the doctor blade squeezes while the handle is pressed between the clamp and the clamping jaw. Figure 3b also shows a portion of the scraper blade 15. Here, the gripping jaw 25 has a width of about 100 mm and a total tool length of about 1900 mm. Appropriate dimensioning of the handle and gripping head provides sufficient force to achieve a permanent grip.

Figures 4a and 4b show in more detail the guide structure 20 belonging to the arrangement according to the invention. The guide structure 20 is shaped according to the doctor blade 15 and may vary in length at different positions. Here, the length of the guide structure 20 is about 1400 mm. In this case, the guide structure extends from the proximity of the end of the blade holder to the opposite side of the blade holder of the frame structure, whereby the doctor blade 30 can be replaced safely. Figure 4b shows the guide structure 20 in more detail. Here, the guide structure 20 is formed of two similar and opposed C-profiles 28. The C-profiles 28 are spaced apart so that the doctor blade 15 fits therebetween. However, the rivets 29 in the doctor blade 15 prevent the doctor blade 15 from leaving the guide structure 20. In other words, the guide structure allows only 9 longitudinal movement of the doctor blade. The guide structure can then be in any position on the web making machine, making it suitable for use with scrapers in different positions. The guide structure is further adapted to extend the blade holder. In Fig. 2b, the distance between the guide structure 20 and the blade holder 16 is about 200 mm.

Figure 4b also shows a guide bar 30 at each end of the guide structure 20, which facilitates the threading of the doctor blade into the guide 20 of the guide 20. The corresponding guide structure 31 is also preferably located at the end of the blade holder 16 (Figure 2a). To support the conductor structure 20 in the frame structure, it also includes a support structure 32. Further, according to the invention, the conductor structure is adapted to be removably attached. This will remove it from the dirt core and break it. The guide structure 20 also includes guide means 33. In Figures 4a and 4b, the guide means 33 are formed as part of the C-bars 34 of the support structure 32. The fastening means corresponding to the guide means are integral with the body structure of the web-making machine. Thus, fastening and detaching the guide structure 20 is quick and easy. Also, the guide guide structure 20 comprising the support structure 32 has locking pins 36 at each end of the support structure 32. Further, the guide structure is preferably symmetrical in the mid-sectional plane. In this case, the guide structure can be threaded into the retaining clamps either way. In this way, the features and limitations of the scraper position can be taken into account and the scraper blade can be replaced as easily as possible.

Figures 5a-5c illustrate a fastening stop 35 according to the invention. 30 The fastening stop 35 consists essentially of one or more, in the embodiment of Figures 5a-5c, two C-rails 37. The number of rails depends on the case, particularly the need to guide the retractable doctor blade. The C-rails 37 are dimensioned and positioned in accordance with the C-rails 34 of the guide structure 20. However, the C-35 rods 34 can be inserted into the C-conductors 37. Further, the length of the C-rails 37 is at least the length of the C-rails 34, whereby a secure attachment is achieved. In particular, Fig. 5c shows a hole 38 at the bottom of the second C-conductor 37, dimensioned according to the above-mentioned locking pin. In practice, when the guide structure is pushed far enough into the retaining engagement, the locking pin locks springwise into the hole, locking the guide structure in place. This fastening stop 35 further includes a guide plate 39 which facilitates the threading of the guide structure to the fastening stops. The C-rails 37 are connected to one another by means of spacers 40, from which the fastening stop 35 can be attached directly to the frame structure 10. On the other hand, preferably, a fastening structure 41 is attached which is fastened to the intermediate supports 40. The fastening structure 41 is shown in Figures 2a and 6, where the fastening structure 41 is fastened around the frame structure 12. Figure 2a shows the flange 42 of the mounting structure 41 having a plurality of oval holes 15 43. Thus, the fastening stops and thus the entire guide structure can be fine-tuned to the correct position and to the maintenance position with the turned blade holder. The fastening stops take up little space so that they can be permanently attached to the frame structure of the web making machine or, for example, to the lever of the calender. Thus, in accordance with the invention 20, the fastening responses are arranged integrally with the frame structure at one or more blade holders. Preferably, all the desired scrapers are fitted with simple fastening stops into which the guide structure can be easily threaded. However, regardless of position, changing the scraper blade is always 25 equally quick, easy and above all safe.

Figure 6 shows one example of the actual positioning of the guide structure 20 and the use of the tool 17. The guide structure is adapted to the respective blade holder, so the guide 30 can be in any position. In the example of Fig. 6, the tip of the doctor blade points obliquely downwards. Preferably, the guide structure 20 further includes support surfaces 44 for supporting the tool 17 when installing or replacing the doctor blade 15. In particular, in the embodiment of Fig. 6, the tool rests on the support surfaces 44 during use, thereby facilitating the movement of the doctor blade 15. The support surfaces also reduce the risk of the tool 11 touching the roll surface. In Fig. 4b, the support surfaces 44 consist of two shaped plate portions which can be utilized with the guide structure in different positions.

The device according to the invention can be made so universal that it is suitable for almost any web-making machine. On the other hand, certain types of positions and scrapers may require special solutions. In any case, especially a device which includes, in addition to the tool described above, a guide structure, guide rails and corresponding fastening stops significantly increase work safety and speed up the installation and replacement of the doctor blade. However, the size of the device may vary from application to application.

The arrangement of the invention can easily be fitted to existing web-making machines. After alignment during installation, the guide structure is easily inserted. The design of the device is simple but sturdy. In addition, as the scraper blade accelerates, production interruptions 20 become shorter. At the same time, the stopping and cooling of hot machine elements is avoided as occupational safety is substantially improved. In addition, even in the most difficult position, one person can change the scraper blade.

Claims (17)

A sheet forming machine equipped with an arrangement for mounting or replacing a blade, wherein between the two frame structures (12) contained in the sheet forming machine is supported a blade holder (16) for a blade (15), and the arrangement comprises means for moving the blade ( 15), characterized in that the devices comprise a hand-operated tool (17) for mounting and replacing a blade (15), which comprises at one end of the gripper (22) for gripping the portion of the blade (15) extending outside the blade holder (16) and at its other end actuators (27) for operating the gripping means (22), extending from the blade holder (16) to the opposite side of the blade holder (16) of the body structure (12). Sheet forming machine according to claim 1, characterized in that the range of the tool (17) is at least 1000 mm. Sheet forming machine according to claim 1 or 2, characterized in that the arrangement further comprises a guide structure (20) arranged to be attached to the frame structure (22), which guide structure extends from near the end of the blade holder (16) to the opposite side of the blade holder (16). the body structure (12). 4. Sheet forming machine according to claim 3, characterized in that a guide structure (20) arranged to allow the blade (15) to move only in its longitudinal direction is arranged 30. According to a blade holder (16) arranged in blade change position as the blade holder ( 16) extension. 5. Sheet forming machine according to claim 3 or 4, characterized in that the guide structure (20) is arranged to be removably fastened. 6. Sheet forming machine according to claim 5, characterized in that the guide structure (20) comprises guide devices (33), whose corresponding fastening stop (35) is fixedly arranged in the body structure (12) opposite one or more blade holders (16). 5 Sheet forming machine according to any of claims 4-6, characterized in that the guide structure (20) comprises supporting surfaces (44) for supporting the tool (17) when mounting or replacing the blade. 10 8. A method of mounting or replacing a doctor blade in a sheet forming machine, wherein the doctor blade is mounted or replaced in a blade holder (16) supported between two input frame structures (12), by touching the doctor blade (15) in the longitudinal direction. , characterized in that, for mounting and replacing the blade (15), the blade (15) is moved with a hand-operated tool (17) from the opposite side of the blade holder of the body structure (12) so that the part of the blade (15) extends outside the blade holder (16) is provided with the gripping means (22) located at one end of the tool, which are actuated by actuating means (27) at the other end of the tool. Method according to claim 8, characterized in that during the mounting of the blade (15), at least part of the distance of the blade (15) extends from the body structure (12) to the blade holder (16) with the tool (17). Method according to claim 8, characterized in that, when replacing the blade (15), at least part of the distance of the blade (30) extends from the blade holder (16) to the body structure (12) with the tool (17). Method according to any of claims 8 to 10, characterized in that, when mounting and replacing the blade (15), the blade (15) is displaced from one and the same side of the body structure (12). Method according to any one of claims 8 - 11, characterized in that the blade (15) is guided to the blade holder (16) or from the blade holder (16) with a guide structure (20) which is supported in the body structure (12) as a extending the blade holder (16) to a position corresponding to the position of a blade holder (16) arranged in blade changing position. Method according to claim 12, characterized in that the same tool (17) and guide structure (20) are used for mounting 10 or replacing more than one blade (15). Method according to any of claims 8 to 13, characterized in that the blade (15) is changed while a machine means (21) which is part of the sheet forming machine and is located in the vicinity of the blade holder (16) rotates. Apparatus for mounting or replacing a doctor blade in a sheet forming machine, which device is intended to be used in a sheet forming machine, where a blade holder (16) for a cabinet blade (15) is supported by a blade holder (16). in that the device is a hand operated tool (17), which includes at one end of the gripper means (22) for gripping the part of the blade (15) which extends outside the blade holder (16) and at its other end of the operating devices (27). ) for actuating the gripping means (22), which is arranged so that when mounting and replacing the blade (15) it extends from the blade holder (16) to the opposite side of the blade holder (16) of the body structure (12). Device according to claim 15, characterized in that the tool (17) is in accordance with claim 2. Device according to claim 16, characterized in that, in addition to the tool (17), the device comprises a guide structure (20), which is in accordance with some of claims 3-7.