FI103680B - Device in the dryer section of a coating device, paper machine or the like - Google Patents

Description

103680

SYSTEM FOR DRYING A COATING MACHINE, PAPER MACHINE OR SIMILAR SAS SA

ANORDNING I TORKPARTIET I EN BESTRYKNINGSANORDNING, PAP-PERSMASKIN ELLER MOTSWARANDE

The present invention is directed to a system as disclosed in the preamble of the first claim below, for lifting and / or lowering overlapping drying boxes or the like, e.g., a thread break, on either side of the coating machine, paper machine or the like, preferably facing each other. , cleaning, other maintenance or similar care.

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The system of the invention typically comprises - a first hydraulic cylinder connected to a first drying box or the like on the first side of the web for raising and / or lowering it, and - a second hydraulic cylinder connected to the second drying box on the other side of the web or the like. / or raised in a direction 20 opposite to the movement of the first drying box.

: Y: It is known to use hydraulic or pneumatic lifting cylinders in paper web coating machines or the like to lift and / or lower devices such as drying boxes or hoods on both sides of the web. The lifting rollers • • · M open the device, for example, during maintenance or at the start of the • · · 'to pass the end of the web through the device.

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The international application wo 96/12150 discloses • Y 30 a previously known way of raising hydraulic cylinders «· ·. box mounted on the web. In this case, the hydraulic cylinders are attached to the ends of the boxes.

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As the size of the boxes increased and thus their weight increased, it was necessary to use up to two pneumatic cylinders or hydraulic cylinders with their machines. The hydraulics system with its units increases the cost of the system.

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Generally, lifting is done using pneumatics instead of hydraulics. Therefore, pneumatic lifting cylinders can be used to lift small dryers. However, the current drying boxes are so heavy that they would require too large and too much bulky pneumatic cylinders, e.g. 320 mm in diameter. Raising one pair of boxes often requires 4 such large cylinders, which of course takes up a lot of space.

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It is therefore an object of the present invention to provide a new improved system for raising and / or lowering pairs of drying boxes or the like.

In particular, it is intended to provide a system whereby the actual lifting can be achieved with less force.

In order to achieve the above purposes, the system of the invention is known for being. presented in the first claims below. in its logo section.

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A typical system according to the invention for lifting and lowering a dryer plate or the like

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in a grinding or paper machine comprises a first and a second hydraulic cylinder • connected to the same closed hydraulic system, one of which is connected to a paper web. a first drying box above to lift this • · · 35, and the second is connected to a drying box below the web for simultaneous lowering, opening the boxes between start-up of the machine, 3 103680 maintenance or the like.

In this typical solution, the hydraulic roller hydraulic fluid, i.e. the system medium, is arranged to flow from the second cylinder, i.e. the lower box connection, to the first, i.e. upper box connected cylinder, when the first or upper drying box is raised.

Thus, in the solution according to the invention, the drying boxes are raised and simultaneously lowered by interconnected hydraulic cylinders in which the oil is transferred from one cylinder to another when one drying box is raised and the other is lowered. The hydraulic system is sized 15 so that the hydraulic cylinders keep the drying boxes in a labile equilibrium state. The cylinder diameters, i.e. the size of the hydraulic cylinder, and the lifting angles of the boxes are selected so that the boxes remain as balanced as possible during all lifting stages. Hereby, the drying boxes 20 can be raised and lowered in a controlled manner with very little force, since the cylinder does not have to actually be raised, but merely defeats a small amount of friction and provides initial acceleration of movement. The lifting can therefore be arranged with a relatively small pneumatic lifting cylinder, or even manually if the dryer is light. The pneumatic lifting cylinder can be controlled by itself • • «. ·. come the traditional way.

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The invention will now be described in more detail with reference to the accompanying drawings, in which: Fig. 1 schematically shows a cross-sectional view of a drying section with a system according to the invention, with drying boxes being used.

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. '". position; #« * ·. 35 Figure 2 shows a cross-sectional view of Figure 1 with the machine boxes in the open position for service or • ·' · *; 103680 4

Figure 3 shows another solution according to the invention according to Figure 1, and

Figure 4 shows the solution of Figure 3 according to Figure 2.

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Figures 1 and 2 show a cross-sectional view of the dryer section 10 of a paper machine or coating machine in the transverse direction of the web 12. A first drying box 14, such as a fluidized bed dryer, is arranged on the web 12 and below the web «! 10 another preferably similar drying box 16.

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Drying boxes 14, 16 are arranged to pivot about support points 18, 20j. In Figure 1, the hydraulic cylinders 22, 24 support the boxes so that their sides 26, 28 facing the web 12 are parallel to the web plane.

The fluid compartments 30, 32 of the hydraulic cylinders are connected to one another by a hose 34 through which oil can flow from a fluid of one hydraulic cylinder into the fluid space of another hydraulic cylinder. A valve 36 is provided in the hose 34 for controlling the flow of oil to control the opening or closing rate of the boxes. The hydraulic cylinders are at 3 V. · 'at one end supported on the machine frame or otherwise::: the support structure shown more closely, by means of the support members 38, 40 = 25, partially pivoted about these support members; ***; tyviksi. The piston rods 42, 44 of the hydraulic cylinders 22, 24 are Ί · · t i. ·. ·. connected from boxes 14, 16 outward from the service side of the machine • ·. ·; ·. protruding ears 46, 48.

Thus, the hydraulic cylinders in the solution according to the invention are supported on a solid machine structure. In the solution according to the invention, the small hydraulic cylinders with a working pressure of over 100 bar, up to 210 - 250 bar.

Next to the upper hydraulic cylinder 22 is mounted a lifting cylinder * ··· * 50 for actuating the lifting or lowering movement, which is pivotally attached at one end to a supporting tongue 52 of the 10363680 machine frame or other structure. the piston rod 54 is connected in the case shown in the figure to the same ear 46 as the piston 42 of the hydraulic cylinder 22 of the upper box 14.

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In the solution according to the invention, considerably less force is required to achieve the lifting than in the previous solutions, whereby a considerably smaller pneumatic cylinder can be used for lifting than before. The diameter of the cylinder 50 is typically about 50 to 100 mm.

As the arm 54 of the lifting cylinder 50 pushes, i.e. lifts the upper box 14 upward to the open position, the ear 46 pulls the piston of the upper box hydraulic cylinder upwards, causing oil to flow in hose 34 toward the reservoir 32 to hose 34. As the oil flows from the blades 20 of the lower box towards the cylinder of the upper box, the piston rod 44 of the lower box 24 begins to project inwardly from the weight of the lower box 16 to lower or open the lower box 16 as shown in Figure 2. about the support points 18, 20 on the drive side 25.

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As the upper box 14 rises to its highest position, the reservoir or fluid chamber 30 of the roller cylinder 22 is substantially filled with oil, whereby this cylinder holds the box ... 30 in the open position. At the same time, the lower box 16 has reached its lowest position so that the piston 44 of the cylinder 24 is * · a 'substantially fully inserted and the reservoir, i.e.: the liquid chamber 32 is emptied of oil. seek to return to the closed position by itself.

In the open position, the weight of the lower box 16 keeps the hydraulic cylinder 103680 6 pushed inside the piston 44 and prevents the oil from flowing freely into its tank 32. On the other hand, the upper cylinder 14's hydraulic cylinder 22 is filled with oil 30, raised or open position. Cylinders 22 and 24 hydraulically balance the boxes to remain in their respective positions.

However, the force exerted by the small pneumatic cylinder 50 can lower the upper box, whereupon the oil begins to flow in the hose 34 in the other direction, from the upper 22 cylinder to the lower 24, and the boxes close or move toward the web. The pneumatic cylinder 50 is thus dual-acting in the embodiment illustrated in the figures, causing the boxes to open and close.

Conventional hose break valves can be fitted to the system for increased safety. On the other hand, the Micro Switches can also be incorporated into the system, which, when detecting an abnormal leakage movement of the boxes, gives an alarm.

In the embodiment of Figures 1 and 2, the treatment side of the upper drying box, the floating box, and the same side of the lower drying box, i.e. the treatment side, are connected to operate together: 9 mi, one for rising and one for lowering.

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In Figures 3 and 4, on the other hand, the service side of the upper dryer box 30 and the drive side of the lower dryer box are connected to work together, so that as the upper tray rises, the lower tray decreases on the operating side. Otherwise, • the hydraulic systems of the boxes correspond to those shown in Figures 1 and 2.

A pump can be provided adjacent to the hydraulic system hose 34 to fill the hose / piping with oil and to compensate for oil leaks. It is also advantageous to connect a valve to the system, by means of which the excess liquid formed due to thermal expansion, for example, can be discharged into the reserve tank.

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The system according to the invention achieves, among other things, the following advantages over the prior art: - increasing safety near the machine when the boxes or the like are balanced and can be raised in a controlled manner; 10 - the actual lifting cylinder is reduced in size and a pneumatic cylinder can be used; - the lifting speed can be adjusted by means of a valve arranged in the hose between the cylinders; - hydraulic cylinder components can be simpler and cheaper than pneumatic lifting cylinders.

The invention is not intended to be limited to the solution exemplified above but, on the contrary, is intended to be widely applied within the scope of the inventive idea defined in the claims below. Thus, there may be two sets of hydraulic cylinders per pair of boxes, one on the service side and the other on the service side, whereby the box pair may be arranged to be opened on each side.

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Claims (10)

103680 l. A system for lifting and / or lowering over-the-web drying boxes (14, 16) or the like arranged on both sides of the web (12), preferably on opposite sides, of the web (12), e.g. or in connection with a similar treatment operation, the system comprising: - a first hydraulic cylinder (22) connected to a first drying box (14) on the first side of the web or the like for raising and / or lowering it, - a second hydraulic cylinder (24) connected to a second drying box (16) on the other side of the web 15 or the like for lowering and / or raising it in a direction opposite to the movement of the first drying box, characterized therein. that - the first and second hydraulic cylinders (22, 24) are coupled to a common closed hydraulic system such that the fluid in the hydraulic system when raising or lowering the drying boxes (14, 16 or the like) moves from the first hydraulic cylinder (22) to the second hydraulic cylinder (24). . ···. A system according to claim 1, characterized in that: - the first hydraulic cylinder (22) is arranged to support the first drying box (14) or the like, 30. the second hydraulic cylinder (24) is arranged to support the III * second drying box (16) or the like and V; - the hydraulic system is dimensioned so that • the hydraulic cylinders keep the drying boxes or the like • essentially in equilibrium, from which one 35 drying box or the like is lightly raised • «· * ·. . y | :! 103,680. A system according to claim 2, characterized in that a lifting cylinder (50), preferably a pneumatic cylinder, is connected to the first drying box (14) or the like to provide a force for lifting the first drying box. System according to Claim 2, characterized in that the first hydraulic cylinder (22) and the lifting cylinder (50) are connected to a drying box (14) on the web (12) and the second hydraulic cylinder (24) is connected to a drying box (16) below the web. ). A system according to claim 1, characterized in that the first hydraulic cylinder (22) is connected to a drying box on the first side of the machine, e.g. the machine maintenance side, and the second hydraulic cylinder on the other side of the machine, e.g. System according to Claim 1, characterized in that the first and second drying boxes (14, 16) are each arranged to pivot about a support point (18, 20) arranged on the other side of the box. 4 «« «4 v: 25 A system according to claim 6, characterized in that the first and second drying boxes are arranged to pivot about support points arranged on the same side of the boxes. • · • * • t · • t · • 8. A system according to claim 6, characterized in that the first and second drying boxes are arranged on opposite sides of the boxes. pivot points. • · • · · • 4 · •:: 35 System according to Claim 1, characterized in that a hydraulic flow regulator (36) is provided in the hose (34) connecting the hydraulic cylinders to control the lifting or lowering speed of the drying boxes. A system according to claim 1, characterized in that the first and second drying boxes have - on the drive side - a pair of hydraulic cylinders belonging to the first hydraulic system and on its service side a pair of hydraulic cylinders 10 belonging to the second hydraulic system. i «i« i * I * Il «i * I I * I * I« I * I * I * I I S il 103680