DE1461144A1 - Dewatering device for a Fourdrinier machine for producing paper or similar fibrous webs - Google Patents

Description

A I5565 August 30, 1965 '

^A 13665 Dr. EM / Zr

Company P. OBERDORPEIi, metal cloth factory, Heidenheim / Brenz

Dewatering device for a Fourdrinier machine for the production of paper or similar fiber tracks *

The "invention relates to the direction of drainage of a Fourdrinier machine for the production of paper or similar fiber webs. The service life of the Fourdrinier is essentially determined by the wear and tear they give way to the so-called flat suction cups of the drainage system suffer, and you: did you? tried on the one hand through suitable material pairings between drainage sieves and flat mammal lining * on the other hand by moving Suction pads in the form of rotating suction boxes ^ Rotabelts or over sieves to reduce wear and tear * These facilities

are not satisfactory, however, partly because of their inadequate effect, partly because of the effort required. Even has been proposed, but is not the state of the art, the friction between the fourdrinier wire and the suction box cover as a result to partially cancel the fact that the fourdrinier in the suction zone from the normal forces acting by the suction force relieved by designing the suction box cover according to the elastic slack line which the sieve assumes under the action of suction force and longitudinal tension, with for taking up the total normal force in front of and support rollers are arranged behind the suction boxes. On this one Proposal builds on the present invention; their goal is., to remedy the disadvantage that the sag curve of the sieve ^ depends on the longitudinal tension of the screen and the. Suction, which changes depending on the type of fabric, so that. an exact Adaptation of the suction box cover to the respective sagging curve not or at least not without special and complex adjustment means is possible. According to the invention, therefore, the fourdrinier wire is arranged over two spaced apart Guided back-up rollers and above the screen, in the middle of the distance, a dandy roll is arranged presses far into the sieve so that the fabric and sieve web wrap around the dandy roll in as large a central angle as possible, while below this wrapping zone a suction cup is arranged, the cover exactly after the deflection

■ The shape of the Fourdrinier is worked, which always has a cutout forms from a cylindrical surface. It succeeds in this way, the suction box cover largely and to relieve normal forces in all operating states and thereby significantly reducing screen wear.

In a further development of the inventive concept, several dandy rolls can alternate between two support rollers be arranged below and above the Fourdrinier wire, the upper dandy roll being expedient in a top wire to run. Such a modification is also possible that the sucker is built into the dandy roll, with his Cover 4er is adapted to the inner surface of the dandy roll and its width of the wrap zone of fabric and Fourdrinier.

Further features and advantages of the invention emerge from the following description of three exemplary embodiments, from the drawings and the claims. They show in a scheraatic representation and viewed from the side: ·. '.. ·. · .. ■.': ..;. ■;> ·: .. ■ ;; ■.; ■■■

Fig. 1 as a first exemplary embodiment, e "L .ei ^^ Erihug ^. with a dandy roll and a'äauge'r, where'der ""

8Q 9B 14/08 5.9- -

Dandy roll presses a cylinder jacket-shaped sag curve onto the fourdrinier wire resting on two support rollers,

Fig. 2 as a second embodiment a device, with the dewatering units according to FIG. 1 arranged alternately above and below the screen are,

3 shows a modification as a third embodiment of the first embodiment.

Designated in all three exemplary embodiments L the fourdrinier wire and S the fabric web, 11 and 12 the support rollers for the fourdrinier wire.

In the first embodiment (Fig. 1) the two support rollers 11 and 12 are at a distance from one another arranged 'and on top of the sieve is in the spacing ridge the dandy roll 13 is stored, which pushes so deep into the fourdrinier that the fabric and the fourdrinier Wrap around it in as large a central angle CXl as possible. I. E. the dandy roll presses the fourdrinier on the middle one Part of its sagging L ^ a cylinder jacket-shaped Deflection so that the cover 14a of the suction cup 14 can be worked exactly after this deflection and In every operating state of the Fourdrinier wire and the dewatering device, it is guaranteed that the Fourdrinier wire is in the the same distance from the suction box cover, which can be kept very small, so that the wire almost

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non-contact runs over the suction cup cover while the Total normal force is almost completely absorbed by the support rollers 11 and 12.

In the second exemplary embodiment (FIG. 2), two dandy rolls 50 and 51 are arranged at a distance from one another and in the upper wire 52 on the upper side of the Fourdrinier wire L and the fabric web S. A third dandy roll 55 is provided on the underside of the Fourdrinier wire L in the middle of the distance between the two upper dandy rolls 50 and 51. As in the first exemplary embodiment, each dandy roll is assigned a suction cup Ik * , IV ¹ and IV '' and each dandy roll presses a deflection corresponding to a partial lateral surface into the fourdrinier wire resting on the support rollers 11, 12, on which, as in the first embodiment, the suction cup cover exactly is adapted.

In the third embodiment (Pig. J), in contrast to the two previous embodiments, the suction cup 100 is in the interior of the dandy roll lOl built in. The dandy roll in turn pushes in between the support rollers H and 12 sagging part of the fourdrinier L a zone, the © inem portion of its outer surface corresponds to, d. H. is a cylindrically curved surface. The AMeakation 100a of the nipple 100 is the inner shape

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* 1461Ί44

adapted to the dandy roll, also in its width the one pressed on by the dandy roll on the fourdrinier and the length of fabric cylindrical surface.

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Claims (2)

PATENT CLAIMS 1. Dewatering device for a Fourdrinier machine the like for the production of paper or / fiber webs, characterized in that the fourdrinier wire (L) is guided over two spaced-apart support rollers (11, 12) and a dandy roll (Ij) is arranged above the fourdrinier wire, which extends so far into the Sieve (L) presses in so that the fabric and sieve web wrap around the dandy roll (13) in as large a central angle CC as possible, while below this looping zone on the other side of the sieve a suction device (14) is arranged, the cover (14a) of which exactly matches the deflection shape of the Fourdrinier wire follows. '· 2. Drainage device according to claim 1, characterized characterized in that between the support rollers (11, 12) several and suction boxes (14 *, 14 ", 14 ^tn ). Dandy roll (50, 51, 53) / alternately below and above of the Fourdrinier wire (L) are arranged, the dandy rolls lying on the upper side of the wire running in an upper wire (52). J. Dewatering device for a Fourdrinier machine for the production of paper or similar fibrous webs, characterized in that the fourdrinier wire (L) has two im. Support rollers (11, 12) arranged at a distance from one another are guided 809 812/0 «59 146114 and a dandy roll (lOl) is arranged above the fourdrinier that presses so far into the sieve (L) that the material and sieve web wrap around the dandy roll in as large a central angle as possible, while inside the dandy roll Sucker (Ho) is arranged, the cover (lOOa) of the inner surface of the dandy roll (lOl) and the width of the wrap zone is adapted. · COPY 809812/0859