FI122119B - Device, system and method for measuring the operating conditions of a roller in a forming or finishing machine - Google Patents

Description

APPLICATION, SYSTEM AND METHOD FOR MEASURING THE ROLLING CONDITIONS OF A ROLLER WITH A BRAINING OR POST-MACHINE

The invention relates to an arrangement on a web forming or finishing machine for measuring the operating conditions of a roll. Further, the invention also relates to a corresponding system and method.

Paper, pulp, tissue and board machines and paper finishing and converting machines have a high number of rotating bodies, for example rolling bearings. Measuring the operating conditions of rolling bearings, such as rollers, is very challenging. Real-time awareness of the actual operating conditions of the rolls would be important, for example, for proper roll operation as well as condition monitoring.

Measurement of operating conditions according to prior art is often based on computational methods. They are somewhat incapable of taking into account, for example, the effects of changing load-bearing harnesses. In the known methods, there is often only one measure which is very remote from the operation of the roll itself. Based on this, the actual operating condition of interest can be calculated / evaluated. Indeed, in such a case, there is no real-time measurement of the actual operating conditions by which the operation of the rolls, or of the production process in general, could be maintained ^ or real-time and rationally adjusted, or could even predict emerging problems or damage.

i-30 It is known in the art to determine the roller bearing lubrication status c in computed loads and in a predetermined Q.

lv. environmental conditions. In reality, the bearing

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However, the operating conditions are made up of several factors co 35 at all. These include ambient temperature and air currents, as well as radial and axial loads from the nip and / or tissues. These loads appear to be substantially affected by the amount which is essentially not taken up by the friction, fit and deformation of the bearing housing and the outer periphery of the bearing. In addition, changes in oil properties (eg viscosity) also contribute to the lubrication situation.

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Due to the above-mentioned factors, it has been very difficult to determine the lubrication situation and the amount of oil supplied to the bearing and contains uncertainties. Lubrication has been followed by the amount of oil supplied to the bearing, which does not indicate the actual 10 lubrication situations.

An improvement here is the so-called self-guided lubricating oil adjustment. It evaluates the lubrication situation using different calculation parameters. The control variable is the oil flow and the control variable is the 15 oil temperature. For adjustment, the machine's speed, oil temperature and maximum load are measured / determined. The maximum load has been estimated from the coarse load information of the roll nip obtained from the pressure of the hydraulics used to load the nip. The oil temperature is measured by sensors. When the 20 sensors have detected a temperature rise in the oil, as a result, the oil flow has been increased.

In addition to lubrication control, the measurement of the load on the bearing is also problematic. In highly loaded roller bearings, micro-movement occurs between the outer periphery of the bearing and the housing. As a result, the metal surfaces become sticky (cold-welded, "micro-contactable"). The free end bearing of the roll cannot co-slide axially in the housing, resulting in an incorrect load on the bearing l '' - »-. As a result, the load ir 30 is distributed in the bearing to only one row of rollers, causing overload and possibly bearing damage. Axial movement can

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^ also prevent the bearing from being blocked. In this case the outer circumference of the bearing oo § tends to tilt in the bearing housing, whereby the periphery of the circumference

Cvl "bites" into the housing, changing the coefficient of friction.

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In bearings with rolling members, a "zero load" also creates a problem. The speed of rotation of the rolling members is slowed down or even stopped due to the frictional resistance caused by the lubricant and the bearing holder if the bearing 5 is very light. On certain rollers, the bearing may be subject to such a zero load situation. Sliding of the rolling elements thins the oil film or even the entire lubricating film fails. Metal-to-metal contact may occur in the bearing, resulting in surface damage and possible bearing damage. Known condition control methods 10 only indicate when a certain level of damage has already occurred.

Generally, the state of the art for monitoring bearing misalignment situations is represented by a temperature sensor arranged on the outer surface 15 of the bearing ring. However, as a measurement method, this is very delayed because heat is forced through the bearing ring. In addition, the temperature measurement performed in this manner is further distorted by the oil flow through the bearing ring to the bearing, which cools the measuring point more than the roller track 20 under load.

In addition to strip machines, it has also been difficult for multi-roll calenders to accurately measure the loads of roller bearings (intermediate rolls and deflection compensated / zone adjustable rolls) 25, which can easily fall into the 0-load range. Bearing-safe drive windows, which can now be defined by calculation alone, cannot be trusted,

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? because the roll deck has unknown frictional forces (for example, in linkage and deflection compensated / zone adjustable x 30 rolls).

σ> m It is also known in the art to apply thin-film sensors to measure operating conditions. From the Finnish patent application number 20065305, it is known to apply a thin film sensor to a paper machine environment. However, the problem with thin film sensing is that the sensing has to be arranged on the load surface itself 4 and thus subjected to high pressure and wear. This places great demands on the implementation of the sensor. In addition, sensing wiring is also challenging because it also needs to be done through the load surface. If, for example, the sensor 5 is to be retrofitted to a roll mounted on the application, then the bearing has to be opened completely in order to access the load surfaces.

The object of the present invention is to provide an arrangement 10 for measuring the operating conditions of a roll by a forming or finishing machine. The invention also relates to a system for measuring the operating conditions of a roll 15 in a web forming or finishing machine, and also to a method whose features are set forth in claims 16 and 22.

In the arrangement according to the invention, the roll is fitted with an optical sensor for measuring operating conditions. Sensoring offers 20 new possibilities for pressure, power and heat measurement in terms of size and design.

Optical sensing can be arranged in connection with the roll in a wide variety of ways. According to one embodiment, the sensor may be located, for example, in the case of a rotating body bearing, behind the surface to which the load is to be applied. According to one embodiment, the rotating portion of the roll may be, for example, a roll casing. co? According to another embodiment, the rotating member may also be an I 'roll axis. The invention is of particular interest in nip rolls,

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£ 30 subjected to axial and radial loads.

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According to one embodiment, the optical sensor may be an example behind the target surface. The sensor may then be located 35, for example, in the main loading area of the circumference. If the support bearing consists of at least two roller tracks, each of the fixed bearings of the support bearings may be loaded with a load

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At least one optical sensor may be provided for the 5 webs. The invention can equally be applied to plain bearings.

According to one embodiment, the optical sensor may be coupled to the control of a forming or finishing machine in one or more purposes. One example of such a purpose is monitoring the condition of the bearing means. Thus, according to one embodiment, the adjustment of the lubricating oil flow of the bearing means 10 can be controlled on the basis of measurement by optical sensing. This can optimize friction losses and even prevent excessive thinning of the lubricant film.

The load applied to the bearing means can also be determined by optical sensing. An example of this is the problematic zero load. On this basis, when the set criterion is met, the bearing can be subjected to an axial load that restores the bearing's functionality.

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Optical sensing can also be applied to the active control of process conditions during operation. In this case, the sensing may be for example in connection with the loading means of the roll.

In accordance with the invention, the operating conditions can be adjusted based on the actual operating conditions, as determined by measurements made by optical sensing. The invention eliminates

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? adjustments based on estimation and computational / theoretical consideration. The real-time x £ 30 awareness provided by the invention enables proactive maintenance and can also prevent damage.

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The arrangement according to the invention is simple in terms of operation, installation, calibration and possible interchangeability. In addition, it is very durable. Other additional advantages obtained by the arrangement, system and method of the invention will be apparent from the description and the features of the appended claims.

The invention, which is not limited to the following embodiments, will be further described with reference to the accompanying drawings, in which:

Figure 1 shows a first embodiment of a bearing according to the invention in a rough ka-10 view,

Figure 2 shows another embodiment of a bearing according to the invention in rough diagram, Figure 3 shows a side view of a bearing according to the invention in rough side view,

Figure 4 is an exemplary diagram of optical sensing,

Figures 5-7 show an example of a measurement principle where intensity measurement is applied, Figure 8 is a diagram of intensity measurement,

Figure 9 shows an example of the shape of a recess,

Fig. 10 shows a first embodiment of an arrangement according to the invention with a central roller of the press, Fig. 11 shows a second embodiment of an arrangement according to the invention with a deflection compensated roll,

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? Fig. 12 shows a third exemplary embodiment of an arrangement according to the invention with a calender caliper roll, t ^. Fig. 13a shows a first embodiment example σ> S of an arrangement according to the invention with online fishers,

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Fig. 13b shows another embodiment of an arrangement according to the invention with a multi-roll calender, 7

Figure 13c illustrates an application example for arranging sensing in a zone shoe,

Figure 13d shows a fourth embodiment of an arrangement according to the invention with a plain bearing roller 5a roll,

Fig. 13e shows an application example for arranging sensing on a plain bearing shoe,

Fig. 14 illustrates an embodiment of a system according to the invention with a web forming machine, Fig. 15 illustrates an embodiment of an application of sensing according to the invention for zero load elimination,

Fig. 16 illustrates an embodiment of an arrangement according to the invention with a press shoe roll, Fig. 17a illustrates an embodiment of a bearing failure and

Fig. 17b shows the measurement data formed from the bearing damage of Fig. 17a by the sensor according to the invention.

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Figures 1 and 2 show, in rough diagrams, some examples of bearing means 11 in connection with which the sensor 12 of the invention can be applied. Such bearings 11 may be one or more, for example, in a forming machine or in a finishing machine. The bearing 11 enables a piece 10 or a part of piece 10 belonging to the machine

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? rotating motion. Some examples of web forming machines N · are paper or board machines (Figure 14),

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£ 30 pulp machines. Some examples of finishing machines include calenders (Figs. 13a and 13b), winders and interleaver.

S The post-processing machine may be part of, or substantially off-line, the actual forming machine.

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35 Some examples of rotating bodies are different rolls, for example nip rolls and cylinders in several different machine assemblies. Examples include suction rolls, press rolls 10.1 (Fig. 10), deflection compensated rolls 10.2 (Fig. 11), drying cylinders, guide rolls, calender rolls, soft calender rolls, heat / thermal rollers 10.3 (Fig. 12), polish 5 ink rollers, tambour and roll rolls, (Figure 16).

Although Figures 1 and 2 show a spherical roller bearing, it is to be understood in this context as just one example of a type of bearing used in a production or finishing machine. Other possible types of bearings could be, for example, cylindrical roller bearings, bevel bearings, tri-ring bearings, plain bearings and pivot bearings.

The spherical roller bearing 11 is used on machines, for example, as a bearing for rotating bodies 11.1, 11.2 (Figs. 10-12). The bearing 11 in its basic form generally consists of an outer ring 16, an inner ring 15 and the rolling members 18 and holders 17 therebetween. The rolling members in this case are rollers 20 18. They roll along the rolling tracks 19.1, 19.2 formed by the rings 15, 16. The holder 17 may surround the rolling members 18.

On the other hand, the holder may be not only a circumferential structure but also a so-called solid holder.

The bearing rings 15, 16 now form two axially adjacent roller tracks 19.1, 19.2. Of course, there may be more roller tracks in the bearing unit 11, or even just one. Patience what? the roller paths 19.1, 19.2 serving as bearings 11.1, 11.2 are in a h · spherical arrangement. In this case, the inner surface of the outer ring 16 16.1

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The £ 30 and the outer surface 15.2 of the inner periphery 15 are in an axially curved shape. For spherical roller bearings 11

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S related basic technology is quite obvious to a person skilled in the art and is therefore not discussed in more detail in this context.

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to sort out. As such, the bearing unit 11 may already be 35 technologies which are fully known or are in the process of being developed, and are not limited in any way by the invention.

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In the embodiment of Figure 1, optical sensing 12 is integrated into the structures of the bearing 11 on its outer periphery 16. The sensing consists of at least one assembly formed by a functional sensor structure 12. There are a total of 5 sensors 12 out of 5 visible.

The sensors 12 may be equally spaced around both roller paths 19.1, 19.2, wherein one or both roller paths 19.1, 19.2 have at least one sensor 12 at a rolling 10 groove. By arranging a plurality of sensors 12 per roller path 19.1, 19.2, circumferential loading, deviations therein, and events in general (not necessarily / merely load) can be indicated.

In the embodiment of Figure 2, the sensors 12 are integrated into the inner ring 15. Here too, both roller tracks 19.1, 19.2 are provided with sensors 12, which are now visible in a total of five.

It will be apparent to one skilled in the art that the basic principle of the invention 20 does not limit the arrangement of the sensors 12 to any particular arrangement on the bearing and their rings 15, 16. The sensors 12 may even be associated with both rings 15, 16. In addition, the number of sensor units 12 or their placement with the bearing 11 may be extremely free within the scope of the basic idea of the invention, taking into account the requirements of each application.

According to one embodiment, the sensors 12, or at least most of them

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The 9 may be provided solely in connection with a bearing 11, such as the bearing bearings 11.1, 11.2 x £ 30 shown in Figures 10 to 12, being located behind one or more of its loadable surfaces 15.2, 16.1.

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The embodiment shown in Figure 1 may have an outer ring 16

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fixed and rotatable with inner tube 15. Examples of such 35 applications are shown in Figures 10 and 12. The embodiment of Fig. 2 is a solid inner tube 15 and a rotational outer ring 16, respectively. A similar example of an application is shown in Figure 11.

Figure 3 shows an embodiment when the bearing 11 is viewed from the side 5. The bearing 11 is shown in its bearing bracket 31. Accordingly, the weighted positioning of the sensors 12 at some point in the circumference is also possible. The optical sensor means 12 may be connected to the fixed periphery 15, 16 of the bearing 11, so that their position is weighted to be in the loading area 30 of the bearing 11.1, 11.2. The loading area 30 is now a sector below the bearing 11 which may be somewhat flexible. The loading area 30 may have sensors 12 more densely than elsewhere in the periphery 16.

Figure 4 shows a possible sensor structure 12 mounted on a rotating body in a rather reduced embodiment. The optical sensor 12 may be integrated into the bearing 11 or sliding surface. The bearing metal 61, such as, for example, the outer ring 16 of the bearing 11, is provided with a recess 65 which extends near the tribological contact surface 68, which is now the inner circumference 16.1 of the outer ring 16 of the bearing. The recess 65 is then located behind the loadable surface 68. One way to make a recess is to use sparking. However, the hole 65 can also be drilled. More generally, the recess 65 may be arranged in a rotating body at a position subject to deformation. Deformations can be caused by a continuous or discontinuous load applied to the surface at 68 o, or

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? pressure. In addition to, or in addition to, the deformation, the changes may be i ^.

also focus on temperature.

£ 30 i ^. For example, surface 68 may be of a slip material type and may be provided with a layer Mi having a thickness S of, for example, 0.02-0.8 mm in the outer ring. The layer Mi follows, for example, steel

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material layer M2. The total thickness H2 35 of the layers Mx and M2 may be, for example, 10 to 80 mm, such as 50 mm.

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The base 63 of the recess 65, or at least the center thereof, is, for example, a polished or otherwise sufficiently light-reflecting surface. The need for polishing or surface treatment depends, for example, on the method of manufacturing the hole 65, and 5 special treatments of the bottom 63 of the hole 65 may not always be necessary. In the following, the base is called the mirror surface 63.

An optical fiber 64 is provided inside the recess 65, which may be formed in a manner known per se, for example from the core 66 and the shell layer 67. The fiber 64 may be introduced into the recess 65, for example, by drilling into a bearing bracket 31. The end of the fiber 64 is at a distance from the mirror surface 63, so that an observation space is formed between the ends of the fiber 64 and the mirror surface 63, i.e. Etalon 62. The distance between the bottom 63 of the recess 65 and the contact surface 68 is T.

The optical fiber 64 and the recess 65 may have, for example, screw threads 86 that are mutually compatible or other similar fastening means. The optical fiber 64 can then be pre-stressed in the recess 65 against its base 63, so that it is always at a distance from the reflective surface 63 at the base 63 of the recess 65, even if there is thermal expansion at the target.

According to one embodiment, Etalon 62 may be filled, for example, with a thermochromic material. One example of this is o, a thermochromic polymer whose color changes with temperature

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you. Even more particularly, an example of such a material is acrylic doped with a thermochromic pigment. In the solution of this embodiment x £ 30, the temperature of the bearing or other surface can be measured by measuring the reflected S radiation from the mirror surface 63. As the color of the thermochromic material changes as the temperature changes, the color of the C 1 light reflected back to the optical fiber 64 changes at the same time and the temperature can be detected by detecting the 35 colors of the light. Detection can be done with color filters by measuring the amount of 12 light transmitted by each filter that passes through different colors. Temperature detection can also be performed using an optically active substance which changes its polarity according to temperature, whereby the temperature can be detected by rotation of the polarization. The advantage of this solution is that the temperature measurement 5 is obtained near the object to be measured. The optical fiber 64 also requires a much smaller hole or recess than, for example, a thermocouple.

Figures 5 to 7 show one principle for measuring the distance 10 of the mirror surface 63. It is to be noted that the invention is by no means intended to be limited to this exemplary method of measurement, but that other possible methods of measurement may equally apply.

Because the mirror surface film 63 formed on the bearing metal 61 moves under pressure from the contact surface 68, the movement of the mirror surface 63 can be used to measure, for example, the pressure exerted by the bearing rollers 18 on the bearing circumference 16. The movement may be, for example, the deflection of the mirror surface 63. The measurement of the movement of the mirror 63 20 may be carried out, for example, by measuring the distance between the end of the optical fiber 64 and the mirror surface 63. The end of the optical fiber 64 can be positioned at a precisely defined distance L from the mirror surface 63. The ends of the fiber 64 have a lens 70 which can be manufactured in a manner known per se to modify the end of the fiber 64. Thus, no separate parts are needed, the fiber 64 £ with its lenses 70 being a single integrated piece. Fiber Lens 70

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^ focuses the light beam 73 from the fiber 64 to the focus point 71. The focus distance 71 is between the end of the fiber 64 and the playing surface 63.

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According to another embodiment, the end of the optical fiber 64 may be M "

For example, Lg attaches to a ceramic fixture which may have two holes for optical fiber. The second hole is the light

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to conduct from the light source to the reference and another to conduct the reflected light 35 for the reference intensity measurement. A third optical fiber 13 can also be mounted on the same bracket to measure surface temperature 63 (for example Fot-Hero). If a standard ceramic component is used at the end of the optical fiber 64, a third hole is provided for this purpose.

Figures 6 and 7 show the effect of changing the distance between the mirror surface 63 and the fiber lens 70. When the mirror surface 63 is in its extreme position as far away from the focusing distance 71 as possible, the light from the core 64 of the fiber 64 diffuses into a wide beam 72 on the mirror surface 63. Now, the mirror surface 63 the intensity of the incident light incident on the core 66 is low. As the mirror surface 63 moves closer to the focusing distance as shown in Figure 7, a greater portion of the reflected light 74 hits the core of the optical fiber 64 66. Thus, by measuring the intensity of the reflected light, the change in distance between the mirror surface 63 and the optical fiber 64 can be measured. When this distance change is calibrated to suit each application, absolute or relative pressure on the surface 68 to be measured can be detected.

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In principle, the mirror surface 63 may be between the optical fiber 64 and the focusing distance 71. Thus, as the distance of the mirror surface 63 changes, the same intensity change occurs as in the example described above. However, the intensity change is less pronounced, so a better result would be achieved with the mirror surface 63 farther away from the focusing distance.

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Fig. 6 shows, for illustrative purposes, a bearing 11 t ^.

contact surface 68 and roller 18 rotating in bearing 11.

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Figure 8 illustrates, in simplified form, one exemplary embodiment of the aforementioned xr g distance measurement. In that light source 77, light is directed to fiber 78, by which light c1-1 is further guided along fiber 79 to sensor 80. For detecting reflected light 35, a junction of detector fiber 14 detector 82, more generally a light detector. The light source 77 may be a superbright LED or other light source of sufficient intensity. The detector 82 is suitable for conventional light detectors. Since the intensity change in the solution according to the invention is strong, the detector may not be required to be very sensitive.

If extremely high measurement accuracy is required, monochromatic or broadband light and the Fabry-Perot principle can be used to measure the distance between the mirror surface and the optical fiber. This measurement method, known per se, is based on the interference of transmitted light and reflected light in the reference. A third alternative to implementing pressure measurement may be to measure the phase shift of the reflected light 15. The result of this measurement is even more accurate.

Figure 9 illustrates by way of example a mechanical solution for implementing the sensor. A shoulder 83 is formed therein in the recess 65 entering the bearing metal 61, against which the sheath 67 of the fiber 64 can be pushed. Thus, the distance between the end of the fiber 64 and the mirror surface 63 can be easily set. In turn, the annular recess 84 is machined at the edges of the mirror surface 63, thus forming narrow brackets 85 on the sides of the mirror surface 63 in bearing metal 61. Now the deflection occurs at the brackets 85 and the mirror surface 63 itself remains straight. It should be noted that the shapes of the recess 65, the shoulder 83 and the recess 84 are shown here simply.

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, rectangular and sharp for straightness. In a real cd? however, the angles in the structure may be shaped such that their N-distortion effect is minimized.

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The dimensioning of the actual sensor structure 12 depends in part on the dimensions of the optical S fiber 64 and partly on the object to be measured itself, whereas the core 64 of the optical fiber 64 has a diameter of about 10 µm to 50 µm. Fiber 64 is surrounded by a protective sleeve 35 having a diameter of about 0.5 to 3 mm. The diameter of the sleeve determines the diameter of the hole 65 made in the bearing metal 61. The thickness T of the film between the load contact surface 68 of the mirror surface 63 and 15 depends on the bearing material 61, the type of contact and the maximum load level. For example, for conventional plain bearings, the thickness of the bearing metal film can be a few hundred 5 micrometers, with the mirror having a maximum travel of a few micrometers. The accuracy of the intensity measurement is about one-hundredth of the 63 movement distances of the mirror. As shown above, in one embodiment, the mirror surface 63 may be farther away from the focal length 71 of the lens 70 of the fiber 64 than the end of the fiber 64. io Focusing distance 71 is suitable for a few hundred micrometers, and the focus can be achieved with slightly inaccurate focus and no need for spot focus. So it is not necessary to measure the exact intensity, but the change in intensity. Otherwise, the sensor 12 must be tuned to its application. 15 In this case, it may be necessary to take into account, inter alia, the penetration of the bearing 11 and the wear of the bearing 11 during long-term use.

The recess 65 of the sensor 12 need not necessarily be made as a closed hole as described above. According to one embodiment 20, the hole 65 required by the sensor 12 can be made through the bearing material 61 and then covered with a film made of a suitable material. The recess 65 may also be made in a separate piece to be inserted into the bearing material 61, such as between the outer periphery 16 of the bearing 11 and the bearing bracket 31 25 (Figure 3). The shape of the bearing 11 or other measurable surface and also its elasticity correspond to the actual bearing material 61.

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By varying the shape of the mirror surface 63, its reflection properties can be affected. The surface 63 can be made either curved x 30 or convex, depending on whether it is desired to hit or bend the light beam upon reflection from the surface 63. If the edges of the base 63 of the recess 65 are shaped as shown in Fig. 9, the shape of the mirror surface 63 remains substantially unchanged because the deflection at the edges is significantly greater than the deflection 35 of the thicker center. On the other hand, the base 63 of the recess 65 may also be made flat. Such a shape may be simpler in manufacturing technology 16. Now, the distance between the end of the optical fiber 64 and the mirror 63 can be adjusted by modifying the sleeve 67 extending past the end of the fiber 64 from the sheath 67 of the fiber 64. Thus, the end of the fiber 64, the bore of the sleeve, and the mirror surface form the measuring space, i.e. 5 standards. One or more of the fibers, or even two fibers can be used for measurement, one of which emits light to the standard and the other receives it. The light used may be broadband, polarized, monochromatic, or otherwise treated, and its wavelength need not be within the wavelength of visible light.

Figures 10 to 12 show some of the arrangements provided by the invention for measuring the operating conditions of a rotating body, such as a roll forming or finishing machine roll 10.1 15 to 10.3. Referring to Figures 10 to 12, it is to be understood that they are not intended to show roll, bearing and machine structures in exact detail, but to be extremely coarse at a very principled level. As previously mentioned, rolls 10.1 to 10.3 include bearing spacers 11 that allow rotation of one or more portions 13, 14 of roll 10.1 to 10.3. Now, these rolls 10.1 to 10.3 are provided, for example, with optical sensor lines 12 as described above for measuring / controlling the operating conditions of the roll and / or the manufacturing process in general.

25 t ~ Figure 10 shows a roughly simplified example

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C \ 1, press roll, more particularly press roll 10.1.

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Figure 14 shows the location of the center roll 10.1 with the press portion 51 of the paper machine N ·.

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The bearing means 11 shown in Figures 1 and 2 are provided in the bearing brackets xj-31 acting as support bearings 11.1. The shaft 14 of the roll 10.1 is, when mounted, connected to the bearing bracket 31, while also rotating the roll shell portion 13. Here, therefore, the rotating element is the roll 35 10.1 with its shaft 14 and the shell 13 along its entire transverse length. For example, the optical sensor means 12 are now 17 in connection with the fixed bearing ring of the bearing bearings 11.1, which is the outer ring 16 of the bearing 11.1. In general, irrespective of the embodiment, the sensors 12 can measure temperature and / or pressure (loads).

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Figure 11 shows an example of a crude simplified roll of a press, more particularly a bend compensated roll of a press 10.2. The deflection compensated and zone adjustable roll 10.2 provides the press portion 51 with the desired web quality throughout the web.

The deflection compensated zone adjustable roll 10.2 can also be applied, for example, with calender 53. Figure 14 shows the position of the deflection compensated roll 10.2, 10.2 'on the press section 51 of the paper machine and also with the online calender 53.

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The spherical roller bearings 11 shown in Figures 1 and 2 are now housed within the shell 13 of the roll 10.2. Here too, they can be said to act as support bearings for the diaper 13 11.2.

The deflection compensated roll 10.2 is loaded on the calender 53 20 against the counter roll 10.3 in a manner known per se.

The deflection compensated roll 10.2 consists of a non-rotatable shaft 14 'and a rotatable roll shell 13 provided with bearing means 11.2 of the invention which rotates about the shaft 14' on the spherical roller bearings 11.2 of the invention. The shaft 14 'inside the sheath 13 is interdependent

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^ infinitely adjustable pame elements 35. Elements 35? support the diaper 13 hydrostatically and with the aid thereof

The deflection of the roll 10.2 is adjusted. The sheath 13 is adjusted, for example, to the shape of the sheath of the counter roll 10.1, 10.3.

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g The shaft 14 of roll 10.2 is connected, for example, by means of pivot bearings 33 o to the bearing brackets 34. The roll shell portion 13 engages the shaft 14 ', for example, by means of roller bearings 11.2. Thus, the rotating element 35 here is the diaper 13. The optical sensor means 12 are now e.g. in connection with the fixed bearing ring 18 of the bearing bearings 11.2 of the diaper 13, which in this case is an inner ring 15 attached to the shaft 14 'of the bearing 11.2. Thus, the sensor 12 may be, for example, 5 at the maximum pressure of the oil film.

Figure 12 shows a roughly simplified example of a calender roll, more particularly a calender thermo roll 10.3. Figure 14 shows the location of the thermo roll 10.3 on the online calender 53 of the papermaking machine and Figs 13a and 13b show applications of fishteroping in which the deflection compensated and / or thermo rolls 10.2, 10.3 according to the invention can be applied. For example, the calender thermo roll may be heated by any suitable heat transfer medium. The nip load, or compressive force 15, depends on the type of paper being manufactured. The basic construction of the calender roll 10.3 largely corresponds to the central press roll 10.1 already described above. Here too, the bearing means 11 are bearing bearings 11.1 in the bearing brackets 31 at the ends of the roll 10.3, in connection with which the optical sensor means 12 are arranged.

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Figure 13a is a schematic illustration of an example of a soft-fish application. It may have a heat roll, such as, for example, a thermal roll 10.3 and a deflection compensated roll 10.2 (e.g., a zone adjustable SYM® type). The transducers 12 according to the invention 25 may be provided on both rollers 10.2, 10.3, for example in their bearings 11.1, 11.2 and / or in the load conditioners 35.

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Figure 13b is a diagrammatic representation of an embodiment of a multi-roll

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£ 30 from lantern 42. The upper roll 10.2 'illustrated at the right edge of the figure can be a fixed deflection roll σ> S compensated roll and the lower roll 10.2 are deflection compensated and oo § also bearable type 11.2. Top and Bottom

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between the slots 10.2 there may be, for example, intermediate rolls and 35 alternating thermo rolls 10.3.

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The lower roll 10.2, shown in more detail in Figure 13b, may be a hydraulically deflection compensated zone adjustable nip roll (for example, applicant's roll type SYM®-Z). The deflection compensation of the roll 10.2 is achieved by hydraulic loading elements 35 on the shaft 14 '5 of the roll 10.2, which act on the shell 13 of the roll 10.2 by supporting it in zones. The loading elements 35 compensate for the deflection of the roll 10.2 in a desired manner to obtain the desired uniform line load. In addition, the load elements 35, in addition to deflection compensation 10, also provide the desired profiling, since each element 35 can be adjusted to the particular profile need. The sensor 12 may be located at different locations on the loading means 35. As an example of the locations, the location of the sensor 12 behind the loading surface 164, 87 of the loading member 35 may be mentioned (Fig. 13c).

Fig. 13c shows an exemplary embodiment for providing sensing to a zone shoe 35. The optical fiber, not now shown, can be introduced from outside the shoe 35 into, for example, its peripheral portions. The exact location of the bore 65.1, 65.2 and the reflective surface at its end is selected according to whether it is desired to measure the pressure and / or temperature of the pocket 164 or slider 87. When measuring the pressure of the pocket 164, the reflective surface may be behind the pocket 164 in the corresponding area, and when measuring the pressure of the heel 87, behind the heel 87. As shown in Figure 13c, the bore 65.2 may also be at least partially horizontal. vertical

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This drilling may have been made through the loading surface of the pocket 164, which is then covered with a film 88 of a suitable material.

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The deflection-compensated roll 10.2 can be so-called impacted or non-impact. In the impacting nip roll (for example, Applicant o roll type SYM®-ZS) between the bearings 11.2 of the roll shell 13 and the shaft 14 'of the roll 10.2, the loading means 35 36 can move the entire shell 13 in the direction of the nip 45. Hereby, a load ring may be provided against the inner surface 15.1 of the bearings 11.2 20 of the shell 13.2, which is known per se and which rests on the shaft 14 'of the roll 10.2. In such an impact roll 10.2, the shell 13 of the roll 10.2 can be secured to the counter roll.

5

If the bearings 11.2 and / or the load ring and / or the hydraulic loading means 36 are provided with sensors 12 according to the invention, the peripheral areas of the track passing through the calender 42 can also be controlled and adjusted more precisely by the load applied to the bearings 11.2. The sensor 12 according to the invention determines the actual load on the edge areas of the roll 10.2. This has a substantially reducing effect on the amount of wreckage generated, for example, since in the past the edges of the web have been wrecked.

15

As is known, the spherical roller bearings 11.2 of the shell 13 end can also be replaced by plain bearings 11.3 known per se. The sensing according to the invention can equally be applied to the plain bearing 11.3 regardless of the roll position.

20 The plain bearing roller may be a self-loading roller with a normal function or a moving sheath. Fig. 13d shows an exemplary embodiment of a schematic sectional view of a roller 10.5 bearing with impact plain bearing. In this case, the position of the sensors 12 may lie behind pockets / cavities 161, 162, 164, 165, 165, for example, of sliding surfaces and / or of sliding bearing elements 114, 115. Fig. 13d shows some exemplary positions o for sensors 12 and Fig. 13e shows an application example antu-co? for arranging the sliding bearing shoe 117.

h- £ 30 Also in Figure 13d, the axis of roll 10.5 is denoted by reference numeral 14 'and the roll mantle by reference numeral 13. The roll mantle 13 is supported

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Sliding bearing members loaded against the inner surface 13 'of the roll shell are provided with seals 170, 171 and pressurized cavities 35 161, 162. , 115 are c1i 21 projecting into the cavities 161, 162 of the plain bearing elements 114, 115. 161, 162. As such, basic technologies for roller bearings for rollers are known to those skilled in the art, and the invention does not require special technical solutions. Reference is made to the applicant's Finnish patent number FI-10 116538.

As shown in Figure 13e, an optical fiber not shown in the figure can be introduced from outside the shoe 117 into its peripheral parts. The exact location of the bore 65 is selected depending on whether the pressure of the 15 pockets 164 or the slide head 87 is to be measured. When measuring the pressure of the pocket 164, the reflective surface may be behind the pocket 164 in its area and when the pressure of the pocket 87 is measured behind the 87 or in the region that the reflective surface exhibits movement as the load changes. As shown in Figure 13e 20, the bore 65.2 may also be at least partially horizontal or oblique. In this case, the vertical drilling can be made through the load surface of the pocket 164, which is then covered with a film 88 made of a suitable material.

25 «- Figure 14 shows an example of a forming machine o, being more particularly a paper machine 37. The paper machine 37 is formed

CD

? a plurality of consecutive subassemblies, such as a headbox 49, a web forming, press and drying member x £ 30 50-52. Prior to the reel 54, there may be, for example, a calendering portion 53. All of this is monitored and managed by the processor unit.

CD

S using the CPU. More specifically, the processor unit means CPU

co o can be understood as machine control and condition automation

CM

100-105.

35 22

The sensor 12 arranged in rotating bodies according to the invention, such as rollers 10.1 to 10.5, can be coupled to the processing unit means CPU. Together, they may form a system for monitoring and / or controlling the operating conditions of the rotating body of the web forming or finishing machine 37, 42 5, such as roll 10.1 to 10.5. The method can be derived directly from a system that represents only one embodiment of putting the basic idea into practice. At least some of the rolls 10.1 through 10.5, such as their bearing and / or loading means 11.1 to 11.3, 114, 115, 35, 36, may be provided with optical sensor means 12 on the machine. They can provide real measurement results for at least one measurable size to the CPU. As a sub-module, the issue can be harnessed to handle the monitoring module 15 100 of the sensors 12 with its communication links 205, which now functions as an optical fiber.

According to a first embodiment, the sensor means 12 can perform condition monitoring of bearings, such as roller / sliding bearings 11.1, 11.2, 11.3 (module 102).

20 In condition monitoring of bearing 11.1, 11.2, 11.3, the optical sensor 12 can detect a problem condition even before the actual damage has started. An abnormal load distribution or load / temperature level indicates an abnormal event and thus provides an opportunity to correct the situation and prevent or prolong damage. The sensor 12 is connected via the automation CPU to monitor the condition of bearings 11.1 to 11.3.

cd o n.

An exemplary problem of condition monitoring, to which the x £ 30 invention can be applied, may arise from the change in roll length due to thermal expansion. This change can cause malfunctions in the bearings 11.1 if the axial oo functions as intended (Figure 12). This may be due, for example, to stickiness caused by microscopic movement of the sliding surfaces. As a result of this, the load on the second roller track o of the bearing 11, the sliding fit 43 between the outer periphery 16 of the bearing 11.1 and the housing 31 does not increase strongly, which is undesirable with respect to the calculated bearing load of the bearing. The sensing 12 detects a drawback in the load and as a result the nip can be opened. Lowering the loads reduces the frictional force on the slider fitting 5, whereby the bearing housing 31 and the outer ring of the bearing 11 move relative to one another and the bearing 11 returns to "alignment". The nipple can then be closed again and returned to the desired load.

According to another embodiment, the sensor 12, 100 according to the invention can be harnessed to optimize the lubrication of bearings 11 such as roller bearings 11.1, 11.2 and / or on the other hand plain bearings 11.3, 114, 115. In the current adjustable circulating lubrication system 101, 300, the setpoint value of the lubricating oil flow for the roller bearings 15 11.1, 11.2 is calculated based on the calculated maximum load and the actual machine speed. In bearings 11.1, 11.2 with optical sensors 12, control of the lubricating oil flow can be made based on actual operating values (load and temperature, or just one) 20. The aim is to keep bearing 11.1, 11.2 within certain limits with the correct oil flow.

In this case, the processing unit CPU 101 can control the oil flow control 25 (control means 41) of the bearing means 11.1, 11.2 of the roll 10.1 10.5 based on the measurement made by the optical sensor means 12. Failure of the lubrication film causes ^ temperature and pressure peaks (load). It can be detected in co? sensing 12 at an early stage before damage occurs and I '- gives corresponding alarms.

£ 30 i'- According to a third embodiment, optical sensor means 12

Using the Oi S, it is also possible to determine on the bearing means 11.1, 11.2 00 the pressure data produced by the sensor 12. One application 35 for this may be a roller bearing 11.1, 11.2 0-load elimination system. A criterion value can be set for the load. Its o load. The load information can be found in the calculation-

CM

for example, when the bearing means 11.1, 11.2 are filled, a small axial load of the set can be applied.

24

By utilizing optical sensors, an active load system 104, 20 can also be incorporated into the bearing 11 to eliminate any overload. Optical sensing 12 can detect, for example, an overload on the second roller track 19.2 or even an indication of an impending overload. If the pressure measurement of the optical sensor 12 indicates, for example, that the load increases on the second roller track 19.2 to a critical area, the position of the fixed periphery of the roller bearing is shifted axially. For example, the offset can be aligned with the free end of the roll. The shift causes the load to be evenly distributed on both lines. For movement control, the feedback can be built 15, for example, from the bearing pressure, which is measured by the sensor 12.

Fig. 15 shows an exemplary embodiment of such an active loading system 20 fitted to the bearing means 11. The free end of the roll may now include actuators 20 for axially loading the fixed periphery 16 of the roll bearing 11 on the basis of a load determination performed using optical sensor means 12. The actuators may, for example, consist of hydraulic cylinders 20 or electric propellers. The actuator (s) 20 may be coupled symmetrically to bearing ring 16 at three points, for example.

δ c \ i, According to yet another embodiment, with optical sensor voltage? line 12 can also measure nip forces (line load) of roll nip structures 45, for example, roller or pivot mounted x 30 roll nip structures 45 (Figure 13b). For example, force measurements can be made from the fixed means of the bearing means 11.1, 11.2

CD

15, 16. Line load can be measured through the roller track and

oo J

o in counter roll via roller / plain bearing. Based on measurements

(M

adjusting and controlling the calendering process with intermediate or deflection compensated rolls (for example, the SYM® roll type developed by the applicant). Thus, the invention allows a wider use of roller bearings with calenders 42, 53.

25

With the invention, the loads of roller bearing rollers (intermediate rolls and deflection compensated SYM® rolls) can also be measured with the inventive roller calipers 42 in accordance with the invention. With this, the prevailing nip forces (line load) can be precisely determined and, in addition, the bearing load can be prevented from drifting into the 0-load range. In the past, line load may have been estimated as a sum, but now even nip profiles can be caught. In addition to the hydraulic loading elements 35, 36, the profiles can also be measured from the surface of the roll shell 13, which may also be provided with a sensor 12 according to the invention. The invention may also account for previously unknown frictional forces in roll roll 10 'such as leverage and deflection

Still another embodiment of the optical sensor 12 according to the invention can be applied even to load measurements behind the sliding surfaces 38 of the slider shoe 39 of the belt roller 10.4 of the press 51 and / or behind the pockets 38 'of its sliding shoes 39. This embodiment is illustrated in Figure 16. Inside the rotary sheath 10.4 'of the belt roll 10.4, there are loading means 40 for loading the sheath 10.4' against the counter roll. The system can measure 25 actual load pressures and / or temperatures. Also, measuring the line load ^ is more accurate, for example, the sensing is in ^ shoe 39. The sensing may comprise a plurality of load elements cd? 39 such as evenly spaced sensors 12. This h-measurement can also be connected to the machine's automatic / condition monitoring system £ 30 (module 104).

Still further, according to a sixth embodiment, the sliding bearing cavity behind the cavities 161, 162, 164, 165 can also be used to measure the actual bearing load pressures and temperatures by 35 optical sensing according to the invention. Further, this solution can also be used for the sliding surfaces of oysters 11.3, 114, 115 and

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26 apply on production machines for condition monitoring. In the plain bearing applications 11.3, 114, 115, the surface pressures are lower than in the roller bearing applications 11.1, 11.2. However, in sliding bearing applications 11.3, 114, 115, the problems are friction and wear 5, particularly in the event of a malfunction.

Figures 17a and 17b show an example of a pilot test in which the optical sensor 12 is mounted on a roller bearing 11 on its outer periphery 16. The bearing is a cylindrical roller bearing 11 having a total of 13 rollers. The bearing 11 has also been tested with two damaged rollers 18.1, 18.2, the results of which are shown in the coordinate system of Figure 17b. It is seen that the sensing 12 can also serve as a condition monitoring sensor. The rollers 18.1, 18.2 of the bearing 11 are damaged in various ways. Roller 18.1 has a 15-point damage to the periphery and roller 18.2 has an entire circumferential damage. The signal-to-time coordinate system shows faulty spikes caused by defective rollers 18.1, 18.2, which are clearly different from signals from other properly flawed rollers, which are relatively identical with respect to each other. The signals 18.1, 18.2 even show the type of damage. The sensing according to the invention is also immediately seen if, under a low load, the speed of the rollers 18 begins to slow down and the contact slips (0-load problem leading to damage).

25 ^ Measuring and control solutions based on optical sensors

CM

, provides a number of significant advantages in a paper machine environment.

CD

First of all, it offers more degrees of freedom to organize the measurement. Now it is also possible to measure the pressure and temperature of the objects x £ 30, which previously could not be performed for one or more reasons. Measurement of pressure and / or cd S temperature is possible without disturbing the sensor. Through the pressure measurement 35 performed by the sensor 12, loads / forces can be accessed.

§ operation of the machine or machine. The sensor is quite simple

CM

27

As noted above, optical sensors 12 can be used in a wide variety of applications in web forming and post-processing machine environments. The sensor solution according to the invention provides new possibilities for pressure and heat measurement also in terms of size.

It is to be understood that the foregoing description and the accompanying drawings are intended only to illustrate the present invention. Thus, the invention is not limited to the embodiments set forth above or as defined in the claims, but many variations and modifications of the invention which are possible within the scope of the inventive concept defined in the appended claims will be apparent to those skilled in the art.

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Claims (29)

Arrangement for measuring the operating conditions of a roller (10.1 - 10.5) in a sheet forming or finishing machine 5 (37, 42), characterized in that optical sensing (12) for integrating in said roller (10.1 - 10.5) has been incorporated. to measure changes in shape and the operating conditions mentioned. Arrangement according to claim 1, characterized in that the optical sensing (12) is arranged to consist of - a surface (63) arranged on the roller (10.1 - 10.5) which reflects light, - equipment (64, 78, 79) for directing light from the light source (77) to said surface (63) and ice equipment (64, 79, 81) to direct the light reflected from the surface (63) to an optical detector (82). Arrangement according to claim 2, characterized in that a recess (65) is provided adjacent to the roller (10.1 - 10.5), on the bottom (63) of which the said 1 light-reflecting surface (63) is arranged. Arrangement according to claim 2 or 3, characterized in that the light conducting equipment (64, 78, 79, 81) are optical fiber conductors which are arranged biased in the recess (65) 2 to compensate for the thermal expansion. (M CD Arrangement according to any one of claims 2-4, characterized in that the opening (65) is arranged at a location in the roll x 30 (10.1 - 10.5) which is subject to deformation. 1 ^ 05 sfr Lg Arrangement according to any of claims 3-5, wherein the roller oo (10.1 - 10.5) has a surface (68) which is arranged to be loaded, characterized in that the depression (65) is arranged behind said loadable surface (68). . Arrangement according to any of claims 1-6, characterized in that said roller is a press roller (10.1, 10.2) or a calender roller (10.2, 10.3, 10.5), which comprises a rotating element (13, equipped with bearing means (11)). 14) and which bearing means (11) comprise the supporting bearings (11.1, 11.2, 11.3, 114, 115) of the roller (10.1 - 10.3, 10.5), having said loadable surface (68). Arrangement according to claim 7, characterized in that the said loadable surface (68) is adjacent to the fixed ring (15, 16) of the bearing (11.1, 11.2). Arrangement according to claim 8, characterized in that said loadable surface (68) is connected to the fixed ring (15, 16) of the support bearing (11.1, 11.2) in its main load area (30). Arrangement according to any one of claims 7-9, characterized in that the bearing (11.1, 11.2) consists of at least two roller webs (19.1, 19.2), where at least one optical sensing (12) is provided for each roller web (19.1, 19.2). ). Arrangement according to any one of claims 1 - 10, characterized in that said rotating element is the shaft (14) of the roller (10.1, 10.3) or the sheath (13) of the roller (10.2, 10.5). δ 12. Arrangement according to any of claims 1 to 11, characterized CD of said roller is a bending compensated roller (10.2, h-10.5), which further comprises devices (35, 36) for the load of x 30 roll (10.2). and wherein said optical sensor hearing (12) is disposed adjacent to said loading devices (35, 36). oo o o CM Arrangement according to claim 12, characterized in that the devices for loading the roller (10.2) comprise a plurality of loading elements (35), in which optical sensing (12) has been provided at least in connection with a part. Arrangement according to any one of claims 1 to 13, characterized in that the bearing devices comprise sliding bearings (11.3, 114, 115), behind whose sliding surfaces and / or behind the pockets and heel spaces of their sliding shoes (161, 162, 164, 165). with optical sensing (12), which the aforementioned operating conditions have been arranged to measure for example load pressure and / or temperature. 10 Arrangement according to any one of claims 1 to 14, characterized in that said roller is a belt roller (10.4), behind the sliding surfaces (38) of the sliding shoe (39) and / or behind the pockets (38) of the sliding shoe (39). ') with optical sensing (12), which is the said operating conditions, has been arranged to measure for example load pressure and / or temperature. A system in a sheet forming or finishing machine (37, 42) for monitoring and / or controlling the operating conditions of a roller (10.1 - 10.5), which system comprises processor unit devices (CPU) which perform monitoring of the machine (37, 42) and / or control and sensor devices (12) arranged to provide measurement results thereto, characterized in that optical sensing (12) ^ is provided at least in part of the roll forming or finishing machine rollers (10.1 - 10.5) arranged to offer said measurement results for the aforementioned CPU unit devices (CPU). co cp h- 17. A system according to claim 16, characterized in that the optical X 30 sensing ring (12) is arranged adjacent to the roller devices (10.1 - 10.5) bearing devices (11.1 - 11.3, 114, 115) to provide S measurement results regarding the operating conditions of at least one roll (10.1 co o - 10.5) to the CPU units (CPU). CM 18. A system according to claim 16 or 17, characterized in that the process unit devices (CPU, 101) are arranged to control the control of the roller devices (11.1 -11.3, 114, 115) of butter, and even solder on the basis of the optical sensing (12) performed the measurement. 19. A system according to any of claims 16 to 18, characterized in that the load directed against the bearing devices (11.1, 11.2) has been arranged for which load a criterion value has been determined, and when this has been fulfilled, a predetermined axial load has been arranged against the bearing devices 10 (11.1, 11.2). 20. System according to claim 19, characterized in that actuators (20) are arranged adjacent the end of the roller to move the fixed ring position of the roller bearings (11) in the axial direction on the basis of the measurement made using the optical sensing. (12). System according to any one of claims 16 - 20, characterized in that with the optical sensing (12) it is arranged to measure the nip forces of the roller nip assemblies (45) by measuring the forces on the fixed rings (15, 16) of the bearing devices (11, 16). behind the loadable surface (68) and on the basis of which measurement has been arranged to control the calender process. 25 Method in a sheet forming or finishing machine ^ (37, 42) for measuring the operating conditions of the roller (10.1 - 10.5), characterized in that the operating ratio of the roller (10.1 - 10.5)? it is measured with the roll (10.1 - 10.5) of integrated optical sensor (12), with which it measures shape changes. Method according to claim 22, characterized in that the control of the lubrication flow of the roller (10.1 - 10.5) bearing devices (11.1, 11.2, and 11.3, 114, 115) is controlled on the basis of the measurement performed with the optical sensing (12). . 35 Method according to any of claims 22 or 23, characterized in that the load directed against the bearing devices (11.1, 11.2) is determined for controlling the bearing devices (11.1, 11.2). directed axial load. 25. A method according to claim 24, characterized in that the position of the roller rings (11.1, 11.2) of the bearing rings (11.1, 11.2) is moved from adjacent to the end of the roller (10.1 - 10.3) at the end of the axial direction on the basis of the measurement made using optical sensing (12). Method according to any one of claims 22 to 25, characterized in that the nip forces of the roll pin structures (45) are measured by optical sensing (12), which is measured on the fixed rings (15, 16) of the bearing devices (15, 16) behind the loadable surface (68) and on the basis of which measurement the calender process is controlled. 20 Method according to any one of claims 22 to 26, characterized in that, by means of optical sensing (12), it is measured for example load pressure and / or temperature behind the sliding surfaces of the sliding bearing (11.3, 114, 115) and / or the pockets / heels of the sliding shoes (161, 162). , 164, 165) such as the aforementioned operating conditions for bearing 25 (11.3). δ 28. A method according to any of claims 22 - 27, characteristic CD -? by measuring it with optical sensing (12) for example I '- load pressure and / or temperature behind the belt roller (10.4) X £ 30 slide shoe (39) slide surfaces (38) and behind the pockets of the slide shoes (39) (38 ') such as the aforesaid operations. CD LO CO (11) for a fiber web machine, according to which method the bearing (11) is composed of an inner ring (15), an outer ring (16) and between these coming roller means (18), characterized in that 29. A method for making or maintaining a bearing (M uses the optical sensor (12) measuring the shape changes in the motionless ring of the bearing (11). 5 δ (M CD O h · · x a CL h - · O) sj- m oo oo (M