FI111658B - Shoe-loaded deflection compensated roller - Google Patents

Description

111658

Shoe-loaded deflection compensated roller

The present invention relates to a shoe-loaded deflection compensated roll of paper / board 5 or finishing machine comprising a stationary roll shaft on which a tubular roll partially or wholly of composite material is rotatably disposed, with a roll roll bearing interposed between the roll axle and the axial belt, a plurality of axially spaced circumferential axial loads are provided between the roll axle and the hydraulic roller shoe acting on the inside of the roll shell and annular zones of low stiffness 15 arranged axially therewith, whereby rigid, the annular zones are formed by coaxially spaced annular stiffeners, the stiffeners on the outer periphery of which are connected by a tubular shell portion, which portion of said shell portion between said stiffeners forms an annular zone 20 of said low stiffness.

Various properties in the direction of the periphery of the sheath and the axis of the roll are required for a shoe-loaded deflection compensated roll, and especially for a roll of such a roll. Deflection-compensated rollers are commonly used as nip rolls, whereby the shape of the diaper 25 should be maintained even at high nip loads. However, in cases where nip pressures are to be profiled along the axis of the roll, the axial stiffness of the roll shell must be low. Conventional deflection compensated rolls are thick-skinned steel rolls, in which case nip pressure profiling requires extremely high forces on the roll shell.

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In order for the diaper to be well profiled, a small stiffness in the axial direction and a corresponding large circumferential direction are required in order not to endanger the load shoe oil membranes.

Although the composite can be made directly by winding such a structure, it does not work as desired because the diaper between the shoes is unsupported and causes loss of oil film at the edge of the shoe.

Initially, such a roll, which is made of steel, is known from 10 Finnish patents 74067. In the case of a composite sheath, such a sheath is not profiled in the desired way, but undergoes sharp deformations leading to paper thickness variations.

It is an object of the invention to provide a shoe-loaded deflection compensated roller 15 having a high-profile, partially or completely composite-material jacket in which the oil film is uniform throughout the load-shoe.

This object is solved in this way and the roll according to the invention is characterized in that the gaps between the stiffeners are filled with a resilient material, preferably resin.

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The portions between the annular stiffeners of the tubular shell portion provide the desired low stiffness in the sheath in the axial direction, while the annular stiffeners attached to the shell portion 25 provide a high circumferential stiffness, thereby ensuring a smooth oil film throughout the shoe.

Advantageous further developments of the invention are set forth in the dependent claims.

The invention will now be described in more detail with reference to the accompanying drawing, in which: 3 111658

Figure 1 shows a schematic longitudinal section of a roll according to the invention.

Figure 2 is a sectional view taken along line II-II of Figure 1.

Figure 1 is a schematic longitudinal section of a shoe-loaded deflection roller 1 provided with a sheath 2 of a paper / board or finishing machine according to the invention.

The roller 1 includes a stationary roller shaft 3. The tubular roller shell 2 is pivotally mounted on the roller shaft 3 by means of end bearings 4,5. Between the roll shoe 2 and the roll shaft 3 there are provided in the nip plane hydraulic loading shoes 6 acting on the inner surface of the roll shell 2 and supported by the hydraulic pressure medium, to which the pressure of the applied fluid medium can be profiled in the direction of the roll axis 3.

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The sheath 2 comprises a plurality of axially and circumferentially substantially annular annular zones 7 arranged at the loading shoes 6 and annular zones 8 of low rigidity arranged therebetween.

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In the embodiment of Figure 1, this is accomplished such that the jacket 2 comprises a plurality of annular stiffeners 9 coaxially spaced apart. The stiffeners 9 form the major part of the stiff zone 7. The stiffeners 9 are connected on the outside by a tubular shell portion 10. The portion of the shell portion 10 between said stiffeners 7 forms said annular zone 8 of low stiffness in the axial direction, while the shell portion 10 at stiffeners 9 further increases the stiffness of the zone 7.

The rigid zones 7 at the loading shoes 6 ensure that the oil film 30 remains uniform over the entire area of the loading shoes 6. In the axial direction 111658 4, the low stiffness annular zones 8, in turn, ensure that the diaper is well profiled.

In order to ensure the uniformity of the oil film, the inner circumference 11 of the stiffener 5 9 is arranged to provide at least the width of the loading shoe 6 for the loading shoe 6 at a width corresponding to the width of the loading shoe 6.

Technically, the annular stiffeners 9 and the tubular casing portion 10 may be formed of discrete parts connected in a manner known per se.

However, it is also possible to arrange that the annular stiffeners 9 and the tubular casing portion 10 are formed as a unitary structure.

The gaps 12 between the stiffeners 9 may be empty, but it is preferable to fill them with a resilient material, preferably resin.

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The material of the sheath 2 may be selected from very different materials depending on the application, but preferably the sheath is formed partly or wholly of a fiber reinforced composite material. The material of the stiffeners 9 may be e.g.

composite, aluminum or steel. By composite is meant a structure comprising reinforcing fibers, e.g. carbon, boron or glass fibers or mixtures thereof, and a matrix material which may be polymeric, ceramic or metallic. The ceramic material comprises various oxides and carbides such as, for example, Al, B, Cr, Ti, Si, Sn, W, · ·

Zn, Zr oxides and carbides or mixtures thereof and various nitrides such as BN and Si3N4.

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Claims (5)

1. Shoe-loaded bend-compensated roller (1) for a paper / cardboard or finishing machine, said roller (1) having a stationary roller shaft (3), on which a tubular roller sheath (2) is partially or completely rotatable by composite material. and which roller sheath (2) at its end is stored at the shaft (3) by means of end bearings (4, 5), whereby between the roller sheath (2) and the shaft (3) is arranged at a nip level in the inner surface of the roller shaft (2). and supported by hydraulic pressure shoes 10 (6) loaded on the shaft (3) of the roller (3), whereby by adjusting the pressure medium fed to the shoes, the roller nip pressure in the direction of the shaft (3) can be profiled, the sheath (2) of the roller (1) having a plurality of substantially rigid, annular zones (7) disposed in the axial direction (6) in the loading shoes (6) and a small stiffness disposed in the axial direction (8), the rigid zones (7) being formed by koaxie spaced apart from each other annular struts (9), which struts (9) on the periphery are joined together by a tubular casing part (10), the intermediate portion of said casing (9) forming its side in said axial direction annular zone (8) of low stiffness, characterized therein, the slots (12) between the struts (9) are filled with flexible material, preferably resin. Roll according to Claim 1, characterized in that the inner periphery (11) of the stiffener (9) is arranged to form a width of at least the loading shoe (6) corresponding to the impact surface of the loading shoe (6). 25 Roll according to claim 1, characterized in that the annular struts (9) and the tubular casing part (10) are formed of separate parts, which are connected to each other. Roll according to Claim 1, characterized in that the annular struts (9) and the tubular casing part (10) are formed as a mutually uniform construction. «Λ f 111658 8 5. Vais according to claim 1, characterized in that the annular struts (9) are of composite material, aluminum or steel. > · * * T