DE29823639U1 - Papermaking stock inlet jet structure - Google Patents

Abstract

The stock inlet for a papermaking machine has an outlet jet (56) across the machine width with at least one wall (4, 5) across the machine width across the pulp flow direction. A number of separate supports (14) are fitted to at least one of the walls (4), to vary the jet (56) opening dimensions in sections to alter the jet delivery forces. The resulting force line (K) of each support (14) is generally at right angles to the machine width and remains on the plane of the pulp flow direction. The adjustments are made on the pulp flow plane in the center section (1). Supports (14, 14') are fitted to two facing walls (4, 5). The center section (1) is divided into zones across the machine width, as a turbulence generator preferably with a number of pulp diffusers. The entry section (2) is divided into sections across the machine width. At least one jet wall (4, 5) swings on an axis (6) across the flow direction and/or slides in the pulp flow direction. The jet walls (4, 5) have a bending stiffness across the machine width, at the supports (14, 14'), of 5 X 109> Nmm2> to 7.5 X 1010> Nmm2> for each 100 mm of wall length in the flow direction. At least one wall (4, 5) is positioned in sections over several separate supports (14, 14'). The separate supports (14, 14') are linked to the center section (1) and the jet wall (4, 5). The supports (14, 14') have no lateral links between them which carry push, pull and/or bending forces. At least one support (14) at a swing wall (4) is in a static model structure with at least three rods, linked together at a point offset from the center section (1) and jet wall (4). At least one rod is near the entry section (2) and at least one further rod is near the wall swing axis (6), while the third rod is at the jet wall (4). The three rods of a support (14) are in or are symmetrical to a plane on the pulp flow line and at right angles to the machine width. The rod near the wall swing axis (6) grips the jet wall (4) directly or indirectly. At least one rod has a variable length, and their mounting points at the center section (1) and/or the jet swing wall (4) can be adjusted. A lifting mechanism (8) acts on all the supports (14) in the same manner, using a pneumatic or hydraulic cylinder and/or an air bellows, through the toggle joints at the rods and/or the effects of temperature. The rod lengths and/or their mounting points are variable in the same direction and amount for all the supports (14), to shift a jet wall (4, 5) in the same direction across the machine width. At least one rod has a variable length for a fine adjustment of the jet wall position, which is activated separately or together with other supports. The model is used to give a one-piece support (7, 10) on the center section (1) or the jet wall (4, 5) with a junction point for a rod. The jet walls (4, 15) are without stiffening ribs and profiles on the lateral direction. Grooves to compensate for tension are at the jet walls (4, 5) on the flow line from the outer flow side. A non-swing jet wall (5) is mounted to the stock inlet foundation by ribs or profiles. The supports (14, 14') at the jet walls (4, 5) are equidistant or they are at different intervals of 50-1000 mm and preferably 200-500 mm. The swing axis (6) of the swing jet wall (4) is close to the center section (1), and a swing axis (24a) is close to the end (15) of the jet. Two swing mountings are between a stock inlet side wall and a side support. The side supports are at the mounting and/or foundation of the stock inlet. At least one adjustable support (12) grips the center section (1) directly or indirectly, at a gap from the end (15) of the jet, so that the bending of the stock inlet structure is the same laterally between and/or outside the support points. The swing axis at the end (15) of the jet is defined by guides where the axis is mounted. At least one support (12) has at least two support units, at different gaps from the end (15) of the jet on the pulp flow direction, giving different lifts, so that the stock inlet swings close to it

Description

Voith Sulzer Paper Technology S 7254-Ku/Bk

Patents GmbH

Headbox

The invention relates to a headbox for a paper machine with an inlet part, a central part extending across the machine width and a nozzle extending across the machine width, which has at least one continuous wall extending across the machine width transversely to the longitudinal flow direction.

The central part can in particular be formed by essentially vertical components which pass through the entire material flow and can therefore withstand compressive and/or tensile forces in the vertical direction over its entire width and extend over the width of the machine.

Headboxes of this type are known, for example, from EP 0 323 468 Bl or EP 0 631 Oil Al. These known headboxes are each divided into sections in the transverse direction, i.e. transverse to the longitudinal direction of the flow. The advantage of such a structure is that the construction is independent of width and in the cost reduction resulting from the handy, reproducible parts. The practical implementation of such designs is difficult, however. For example, a relatively large amount of effort must be made in the areas affected by the flow in order to prevent the accumulation of fibers and the like at the section boundaries. The cost advantage previously achieved is thus canceled out.

The invention is based on the object of creating an improved, cost-effective headbox of the type mentioned at the outset, in which the problems mentioned above are eliminated.

This object is achieved according to the invention by the features specified in the characterising part of claim 1.

According to the invention, at least essentially only those elements of the headbox that come into contact with the material flow can be designed in a modular design that are not adjustable relative to one another. By combining modular components and components that extend at least essentially over the entire width, the aforementioned advantages of a modular design are thus used on the one hand, while on the other hand, deposits of fibers and the like on the adjustment joints are practically excluded without additional effort. In particular, flow-guiding parts following the central part are not designed in a modular way, while at least one nozzle wall is supported by several separate support devices distributed across the width of the machine. This means that the expansion forces that occur as a result of the internal pressure of the nozzle are absorbed relatively evenly across the width. Temperature differences in the support devices, as are known from practice, no longer have any effect on the accuracy of the nozzle gap due to the division into individual modules.

In particular, support devices can also be attached to two opposite walls.

In a practical embodiment, the central part is divided into sections across the width of the machine. Alternatively or additionally, the inlet part can also be divided into sections across the width of the machine.

The central part can, for example, be designed as a turbulence generator and preferably comprise several stage diffusers.

Conveniently, at least one nozzle wall is mounted so as to be pivotable about an axis extending transversely to the flow direction and/or displaceable in the flow direction.

Advantageously, at least one continuous nozzle wall supported by several separate support devices is provided, the bending stiffness of which in the transverse direction, ie in the direction of the machine width, is in a range from about 5 x 10 ⁹ Nmm ² to about 7.5 x 10 ¹⁰ Nmm ² per 100 mm of wall length extending in the direction of flow. This ensures that the sections are "decoupled" with regard to deformation.

Preferably, at least one continuous nozzle wall supported by several separate support devices can be positioned section by section via the individual support devices.

In a preferred practical embodiment of the headbox according to the invention, the various support devices are individually connected to the central part and the relevant nozzle wall.

It is particularly advantageous if at least one support device assigned to a pivotable nozzle wall corresponds to a static model with at least three rods which are brought together at a distance from the central part and the pivotable nozzle wall at least substantially in a node, with at least one rod acting on the central part near the inlet part and at least one further rod near the pivot axis, and at least a third rod acting on the pivotably mounted nozzle wall, and that the at least three rods of a respective support device are arranged in or symmetrically to a plane which runs perpendicular to the direction of the machine width and in the longitudinal direction of flow.

Conveniently, the length of at least one rod is variable.

It is also advantageous if the position of at least one point of application of the rods on the central part and/or on the pivotable nozzle wall can be changed.

The support devices acting on the nozzle wall can be connected to the central part via a base plate, for example.

According to a further advantageous possible embodiment, at least one support device comprises a support part that establishes the connection to the central part and/or to the nozzle wall. Such a support part can consist, for example, of a one-piece cast or welded part.

The nozzle walls are expediently designed without stiffening ribs and stiffening profiles extending in the transverse direction.

Grooves running in the direction of flow to even out the tension can be provided on the outer sides of the nozzle walls facing away from the flow.

In a preferred embodiment, the headbox can be pivoted about an imaginary transverse axis, preferably provided in the area of the nozzle end, which acts directly or indirectly on the central part. Thus, by pivoting the headbox accordingly, the point of impact of the material jet on a downstream dewatering unit can be adjusted. Such a design of the headbox is therefore also advantageous regardless of the modular design.

The pivot axis of the pivotable headbox can be defined in different ways. For example, two pivot bearings can be provided, each arranged between a headbox side wall and a lateral support. In principle, the pivot axis, which is preferably provided in the area of the nozzle end, can also be defined by guides in which the headbox is mounted accordingly.

In a practical embodiment, the headbox is supported on at least one support device, which comprises at least two support units, which in particular have two support points at different distances from the nozzle end in the direction of flow.

• ■··*· t «

and carry out different strokes so that the headbox can be pivoted approximately around the nozzle end.

An inlet plate can be assigned to the central part on the inflow side, which serves to stiffen the central part and/or as a fastening element for further functional elements and which extends transversely to the flow direction over at least substantially the entire width of the central part. Such an inlet plate can be involved in particular in absorbing forces from the hydraulic pressure of the material flow.

In an expedient embodiment of the headbox according to the invention, at least one nozzle wall is mounted on a support part fastened to the central part so as to be generally displaceable in the direction of flow.

Further advantageous embodiments of the headbox according to the invention are specified in the subclaims.

The invention is explained in more detail below using exemplary embodiments with reference to the drawing, in which:

Fig. 1 is a schematic, partially sectioned side view of a

first embodiment of a headbox,

Fig. 2 is a schematic front view of the headbox according to Fig.

1 in the direction of arrow X,

Fig. 3 is a schematic, partially sectioned side view of a

Design of a pivoting headbox,

Fig. 4 is a schematic, partially sectioned side view of a

another embodiment of a pivoting headbox,

Fig. 5 is a schematic, partially sectioned side view of a

another embodiment of a headbox with a movable nozzle wall and a schematically shown support device formed by a rod construction, the middle rod of which engages the central part,

Fig. 6 is a section through the adjustment device associated with the movable nozzle wall, cut along the line I - I of Figure 5,

Fig. 7 is a schematic, partially sectioned side view of a

another embodiment of a headbox comparable to that in Fig. 5 with a schematically shown support device formed by a rod construction, the middle rod of which, however, engages the pivotable nozzle wall,

Fig. 8 is a schematic, partially sectioned side view of a

another embodiment of a headbox comparable to that in Fig. 5 with a schematically shown support device formed by a rod construction, the middle rod of which, however, engages the joint of the pivotable nozzle wall, and

Fig. 9 is a schematic, partially sectioned side view of a

another embodiment of a headbox comparable to that in Fig. 5, showing two of the support devices distributed over the mesh width.

The headbox for a paper machine shown purely schematically in Figures 1 and 2 comprises an inlet part 2, a central part 1 and a nozzle 56.

The nozzle 56 is provided with two continuous walls 4, 5 extending transversely to the longitudinal flow direction across the machine width, to which a plurality of separate support devices 14 and 14' distributed across the machine width are assigned in order to absorb and dissipate nozzle expansion forces.

The inlet part 2 is supplied with fiber suspension via individual supply bores 18. The supply bores 18 are connected either to longer individual hoses 3 or directly to a common distribution pipe 19, which is arranged essentially parallel to the outlet gap.

In the present case, the central part 1 is designed as a turbulence generator and is provided with several step diffusers. The flow is guided via the upper nozzle wall 4 and the lower nozzle wall 5 to a jet outlet 15, where the material jet finally exits at an angle α to the horizontal.

The upper continuous nozzle wall 4 is pivotally mounted about an axis 6 extending transversely to the longitudinal direction of the flow and arranged near the central block or central part 1. In the present case, this pivot axis 6 is defined by a hinge or joint divided into sections transversely to the direction of flow across the width of the machine. This hinge defining the pivot axis 6 is mounted in the supports 7 assigned to the support devices 14.

In the direction of the jet outlet 15, the pivotable upper nozzle wall is supported by lifting gears 8, which are also assigned to the support devices 14 and are hinged to the top of the supports 7, each of which acts on the nozzle wall 4 via a bridge member 9. As a result, the support forces resulting from the hydraulic pressure in the nozzle 56 are introduced into the central part 1 via the lifting gears 8 and the supports 7. The resulting force lines K of each support device 14, which comprises a bridge member 9, a lifting gear 8 and a support 7, lie in a plane oriented in the direction of flow and perpendicular to the direction of the mesh width.

The supports 7 are firmly connected and, for example, screwed to the central part 1 via a corresponding number of base plates 7a or via at least one common base plate. Apart from that, these supports 7 are not connected to one another transversely to the flow direction.

Accordingly, support devices assigned to the lower nozzle wall 5 can be connected to the central part 1 via one or more base plates 10a.

If the nozzle walls 4 and 5 are now pushed apart due to the internal nozzle pressure, the resulting expansion forces are absorbed evenly across the width due to the modular support devices 14 and 14' distributed across the width of the machine. The structure is such that the force lines K run in a C-shape when viewed from the side of the headbox. As can be seen from Fig. 1, both tensile and compressive forces run through the central part 1.

The machine-wide material jet emerging from the exit gap or jet outlet 15 reaches an endless, rotating screen belt 17 in the area of a breast roller 16 in the usual manner.

As can be seen from Fig. 2, drive pins 20 of lifting gears 8 lying next to one another are connected to one another in an exclusively torsionally rigid manner via a drive shaft 21 which is divided into sections across the width of the machine transversely to the direction of flow, so that when an associated drive 22 is actuated, the nozzle wall 4 (see also Fig. 1) is moved in the same way across the entire width, without any other tensioning forces being transmitted by the drive shaft 21.

The lower nozzle wall 5 can basically be supported in the same way as the upper nozzle wall 4, for which purpose modular support devices 14' can be provided, distributed over the width of the machine and each provided with a lifting gear 12. A rigid support part 10 designed as a support module absorbs the hydraulic forces of the nozzle wall 5 and transmits them to the central part 1 forming a central block. By arranging several support devices in a row,

By means of the support devices 14' across the machine width, the lower nozzle wall 5 is supported evenly across the entire machine width.

Both with regard to the upper modular support devices 14 and with regard to the lower modular support devices 14', the respective module division can be defined according to the respective circumstances. For example, a division length in a range of approximately 50 to approximately 1000 mm and preferably in a range of approximately 200 to 500 mm is conceivable.

The central part 1 gives the entire headbox structure the desired rigidity. This can be further increased by an inlet plate 11 assigned to the inflow side of the central part 1 preferably extending beyond the height of the inlet part 2. This inlet plate 11, which preferably extends at least substantially over the entire width of the central part 1, can simultaneously serve as a structural component of the inlet part 2.

The entire headbox is pivotably mounted about an axis 24a provided in the area of the nozzle end or jet outlet 15, so that a corresponding jet angle adjustment is possible. In the present case, each side wall 23 of the headbox is assigned a journal bearing 24, which is attached to a support 25. The supports 25 are attached, for example, to a frame and/or a headbox foundation. The pivoting movement is effected by at least one lifting gear 12, which is advantageously positioned in the area of the center of gravity of the headbox.

Fig. 3 shows a schematic, partially sectioned side view of an embodiment of a headbox that can be pivoted as a whole. In this case, the headbox is mounted on at least one support device 12, which comprises at least two support units 40, 41, which define two support points that are at different distances from the nozzle end or jet outlet 15 in the direction of flow and execute different strokes, so that the headbox can be pivoted approximately around the nozzle end 15. In the following case, the two support units 40, 41 engage the lower rigid support part 10.

Otherwise, this embodiment can have the same structure as that according to Figures 1 and 2, wherein corresponding parts are assigned the same reference numerals.

Fig. 4 shows a schematic, partially sectioned side view of another embodiment of a pivotable headbox. In the present case, the pivot axis of the headbox, which is preferably provided in the area of the nozzle end 15, is defined by guides 30 in which the headbox is mounted accordingly. By activating an associated adjusting device 31, the headbox can then be pivoted about the imaginary axis defined by the guides 30 and located in the area of the nozzle end.

Furthermore, this embodiment can also have the same structure as that according to Figures 1 and 2, wherein corresponding parts are again assigned the same reference numerals.

Figures 5 and 6 show a purely schematic representation of another embodiment of a headbox in which the lower nozzle wall 5 is slidably mounted on the support part 10 and can be moved relative to it in the longitudinal direction of the flow. The nozzle wall 5 can be moved in the desired direction via at least one adjustment device 48, for example a mechanical, hydraulic and/or pneumatic one. In the present case, this adjustment device 48 acts on the support part 10 and the nozzle wall 5.

As can be seen from Figures 5 and 6, the adjustment device 48 comprises two pivot pins 50 mounted in the support part 10, each of which has an eccentric extension 51 that engages in a groove 55 provided in the nozzle wall 4. The pivot pins 50 carry levers 52 with integrated pivoting nuts 53 that can be actuated via a common adjustment spindle 54 (see Figure 6) with opposing threads. The eccentric attachments 51 can preferably be detached from the respective pivot pin 50.

Otherwise, this embodiment can again have the same structure as that according to Figures 1 and 2, wherein corresponding parts are again assigned the same reference numerals.

In addition, Fig. 5 shows a purely schematic representation of an embodiment of a respective support device 14, as is also conceivable in particular in the other embodiments of the headbox.

Thus, a respective support device 14 is formed by a rod structure which in the present case comprises three rods 57, 58 and 59 which are supported in a spread arrangement on the central part 1 and/or the upper nozzle wall 4 and converge at a distance therefrom at least substantially in a node point 60.

The support devices 14 assigned to the pivotable nozzle wall 4 therefore each correspond to a static model with, in the present case, three rods 57, 58, 59 which are brought together at a distance from the central part 1 and the pivotable nozzle wall 4 at least essentially in the node 60, with the rod 57 near the inlet part 2 acting on the central part 1, the middle rod 58 near the pivot axis 6 and the third rod 59 acting on the pivotably mounted nozzle wall 4. The rods 57, 58 and 59 of a respective support device 14 are arranged in or symmetrically to a plane which runs perpendicular to the direction of the machine width and in the direction of flow. In the present case, the rods 57, 58 and 59 are in a plane running perpendicular to the direction of the machine width and in the longitudinal direction of flow, i.e. in the drawing plane of Figure 5.

In the embodiment shown in Fig. 5, the rod 58 provided near the pivot axis 6 engages the central part 1 directly or indirectly.

Fig. 7 shows a schematic, partially sectioned side view of another embodiment of a headbox comparable to that of Fig. 5 with a schematically shown, by a framework construction,

tion formed support device 14, the middle rod 58 of which is provided near the pivot axis 6, however, acts directly or indirectly on the nozzle wall 4 pivotally mounted about the axis 6.

Otherwise, this embodiment has the same structure as that according to Figures 5 and 6, wherein corresponding parts are assigned the same reference numerals.

Fig. 8 shows a schematic, partially sectioned side view of another embodiment of a headbox comparable to that of Fig. 5 with upper support devices 14 each formed by a rod structure. In the present embodiment, this middle rod 58 of a respective support device 14 engages the joint of the pivotable upper nozzle wall 4 defining the pivot axis 6. The left part of Fig. 8 shows the view x of the anchoring of a rod end to the nozzle wall.

Otherwise, this embodiment can have the same structure as that according to Fig. 5, wherein corresponding parts are again assigned the same reference numerals.

Fig. 9 shows a schematic, partially sectioned side view of another embodiment of a headbox comparable to that in Fig. 5, in which two of the support devices 14 distributed across the width of the machine are shown. In this Fig. 9, a coordinate system with the axes X, Y and Z is also indicated. The X direction coincides with the width direction of the paper machine, while the Y direction coincides with the longitudinal flow direction. The Z direction

runs perpendicular to the X-Y plane. Accordingly, the support devices 14 are arranged one behind the other in the X direction, while the rods 57, 58 and 59 of a respective support device 14 each lie in a y-z plane. The continuous upper nozzle wall 4 supported by these separate support devices 14 can thus be positioned section by section via the individual support devices 14.

In the present case, the middle rods 58 engage directly or indirectly on the central part 1. In principle, however, such a rod construction is also possible, for example, in which the middle rod 58 of a respective support device 14 engages directly or indirectly on the pivotably mounted nozzle wall 4 or on the joint defining the pivot axis.

Furthermore, this embodiment can also have the same structure as the previous embodiments, with corresponding parts again being provided with the same reference numerals.

On the outer sides of the nozzle walls 4 facing away from the flow, grooves 62 running in the direction of flow can be provided to even out the tension, as can be seen, for example, in Fig. 9.

List of reference symbols

1 Central part 2 Inlet part 3 Supply lines 4 upper nozzle wall 5 lower nozzle wall 6 Swivel axis 7 Support 7a Base plates 8th Lifting gear 9 Bridge link 10 Support section 10a Base plate 11 Inlet plate 12 Lifting gear 14 Supporting devices 14' Supporting devices 15 Jet outlet, nozzle end 16 Breast roller 17 Sieve belt 18 Drilling 19 Cross distribution pipe 20 Drive pin 21 drive shaft 22 drive 23 Side wall

18

24 journal bearing 24a axis 25 Support 30 guides 31 Adjustment device 40 Support unit 41 Support unit 48 Adjustment device 50 Pivot bolt 51 eccentric attachment 52 lever 53 Nuts 54 Adjusting spindle 55 Groove 56 jet 57 Rod 58 Rod 59 Rod 60 Node 62 Grooves K Lines of force &agr; angle

Claims (43)

1. Headbox for a paper machine with an inlet part ( 2 ), a central part ( 1 ) extending across the machine width and a nozzle ( 56 ) extending across the machine width, which has at least one continuous wall ( 4 , 5 ) extending across the machine width transversely to the longitudinal flow direction, characterized in that for section-by-section absorption and dissipation of nozzle expansion forces, several individual support devices ( 14 ) distributed across the machine width and separate for influencing the nozzle opening ( 15 ) are attached to at least one preferably continuous wall ( 4 ), wherein the resulting line of force (K) of each support device ( 14 ) remains at least substantially in a plane perpendicular to the direction of the machine width and in the direction of flow and the corresponding support forces are individually introduced into the central part ( 1 ) and absorbed at least substantially in the respective associated plane in the direction of flow. 2. Headbox according to claim 1, characterized in that support devices ( 14 , 14 ') are attached to two opposite walls ( 4 , 5 ). 3. Headbox according to claim 1 or 2, characterized in that the central part ( 1 ) is divided into sections across the machine width. 4. Headbox according to one of the preceding claims, characterized in that the central part ( 1 ) is designed as a turbulence generator and preferably comprises several stage diffusers. 5. Headbox according to one of the preceding claims, characterized in that the inlet part ( 2 ) is divided into sections across the machine width. 6. Headbox according to one of the preceding claims, characterized in that at least one nozzle wall ( 4 , 5 ) is mounted so as to be pivotable about an axis ( 6 ) extending transversely to the flow direction and/or displaceable in the flow direction. 7. Headbox according to one of the preceding claims, characterized in that at least one continuous nozzle wall ( 4 , 5 ) supported by several separate support devices ( 14 , 14 ') is provided, the bending stiffness of which in the transverse direction, ie in the direction of the machine width, is in a range from about 5 × 10 ⁹ Nmm ² to about 7.5 × 10 ¹⁰ Nmm ² per 100 mm of wall length measured in the flow direction. 8. Headbox according to one of the preceding claims, characterized in that at least one continuous nozzle wall ( 4 , 5 ) supported by several separate support devices ( 14 , 14 ') can be positioned section by section via the individual support devices ( 14 , 14 '). 9. Headbox according to one of the preceding claims, characterized in that the various support devices ( 14 , 14 ') are individually connected to the central part ( 1 ) and the relevant nozzle wall ( 4 , 5 ). 10. Headbox according to one of the preceding claims, characterized in that the various support devices ( 14 , 14 ') have at least substantially no transverse connections between one another which transmit tensile, compressive and/or bending forces. 11. Headbox according to one of the preceding claims, characterized in that at least one support device ( 14 ) associated with a pivotable nozzle wall ( 4 ) corresponds to a static model with at least three rods ( 57 , 58 , 59 ) which are brought together at a distance from the central part ( 1 ) and the pivotable nozzle wall ( 4 ) at least substantially in a node ( 60 ), with at least one rod ( 57 ) acting on the central part ( 1 ) near the inlet part ( 2 ) and at least one further rod near the pivot axis ( 6 ), and at least a third rod acting on the pivotably mounted nozzle wall ( 4 ), and that the at least three rods ( 57 , 58 , 59 ) of a respective support device ( 14 ) are arranged in or symmetrically to a plane which is perpendicular to the direction of the machine width and in Flow longitudinal direction. 12. Headbox according to claim 11, characterized in that the rod ( 58 ) provided near the pivot axis ( 6 ) acts directly or indirectly on the pivotably mounted nozzle wall ( 4 ). 13. Headbox according to one of the preceding claims, characterized in that the length of at least one rod ( 57 , 58 , 59 ) is variable. 14. Headbox according to one of the preceding claims, characterized in that the position of at least one point of engagement of the rods ( 57 , 58 , 59 ) on the central part ( 1 ) and/or on the pivotable nozzle wall ( 4 ) is variable. 15. Headbox according to claim 13 or 14, characterized in that a respective change in all support devices ( 14 , 14 ') takes place in a similar manner and preferably by means of a lifting gear ( 8 ), a pneumatic or hydraulic cylinder and/or an air spring bellows, via toggle joints associated with the rods ( 57 , 58 , 59 ) and/or by the influence of temperature. 16. Headbox according to one of the preceding claims, characterized in that the rod lengths and/or the position of the points of attack in all support devices ( 14 , 14 ') can be changed simultaneously, in the same direction and uniformly in order to move a respective pivotable nozzle wall ( 4 , 5 ) in the same way over the entire width measured in the direction of the machine width. 17. Headbox according to claim 15, characterized in that the support devices ( 14 , 14 ') each comprise at least one rod ( 57 , 58 , 59 ) to which a device for individual additional fine adjustment of the nozzle wall ( 14 , 14 ') is assigned. 18. Headbox according to claim 17, characterized in that the fine adjustment devices assigned to the various support devices ( 14 , 14 ') can be activated individually or together with others. 19. Headbox according to claim 11, characterized in that a one-piece support ( 7 , 10 ) is formed from the bars ( 57 , 58 ) of the described model, which is supported on the central part ( 1 ). 20. Headbox according to claim 11, characterized in that a one-piece support is formed from the rods ( 58 , 59 ) of the described model, which is supported on the nozzle wall ( 4 , 5 ) and which has a node ( 60 ) in which the rod ( 57 ) engages. 21. Headbox according to one of the preceding claims, characterized in that the nozzle walls ( 4 , 5 ) are designed without stiffening ribs and stiffening profiles extending in the transverse direction. 22. Headbox according to one of the preceding claims, characterized in that grooves ( 62 ) running in the direction of flow and serving to even out the tension are provided on the outer sides of the nozzle walls ( 4 , 5 ) facing away from the flow. 23. Headbox according to one of the preceding claims, characterized in that a non-pivotable nozzle wall ( 5 ) is provided which is connected to a headbox foundation via ribs or profiles. 24. Headbox according to one of the preceding claims, characterized in that the pitch distances of the support devices ( 14 , 14 ') assigned to a respective nozzle wall ( 4 , 5 ) are of equal size. 25. Headbox according to one of claims 1 to 23, characterized in that the pitch distances of the support devices ( 14 , 14 ') assigned to a respective nozzle wall ( 4 , 5 ) are at least partially different from one another. 26. Headbox according to one of the preceding claims, characterized in that the pitch distances of the support devices ( 14 , 14 ') assigned to a respective nozzle wall ( 4 , 5 ) are in a range from about 50 to about 1000 mm and preferably in a range from about 200 to about 500 mm. 27. Headbox according to one of the preceding claims, characterized in that the pivot axis ( 6 ) of the pivotable nozzle wall ( 4 ) is arranged close to the central part ( 1 ). 28. Headbox according to one of the preceding claims, characterized in that it is pivotable about a transverse axis ( 24a ) preferably provided in the region of the nozzle end ( 15 ). 29. Headbox according to claim 28, characterized in that two pivot bearings ( 24 ) are provided, each arranged between a headbox side wall ( 23 ) and a lateral support ( 25 ). 30. Headbox according to claim 29, characterized in that the supports ( 25 ) are attached to a frame and/or a headbox foundation. 31. Headbox according to one of the preceding claims, characterized in that it is pivotable by means of at least one adjustable support device ( 12 ) which acts directly or indirectly on the central part ( 1 ). 32. Headbox according to claim 31, characterized in that the at least one support device ( 12 ) is provided at a distance from the nozzle end ( 15 ) in the region of the central part ( 1 ). 33. Headbox according to one of the preceding claims, characterized in that it can be pivoted by means of several support devices ( 12 ) which are distributed over the machine width in such a way that the deflection of the headbox structure in the transverse direction between and/or outside the support points is at least substantially equal. 34. Headbox according to one of the preceding claims, characterized in that its pivot axis, preferably provided in the region of the nozzle end ( 15 ), is defined by guides ( 30 ) in which it is correspondingly mounted. 35. Headbox according to one of the preceding claims, characterized in that it is mounted on at least one support device ( 12 ) which comprises at least two support units ( 40 , 41 ) which define two support points which are at different distances from the nozzle end ( 15 ) in the direction of flow and which execute different strokes so that the headbox can be pivoted approximately about the nozzle end ( 15 ). 36. Headbox according to one of the preceding claims, characterized in that the central part ( 1 ) is assigned on the inflow side an inlet plate ( 11 ) which serves to stiffen the central part ( 1 ) and/or as a fastening element for further functional elements and which extends transversely to the flow direction over at least substantially the entire width of the central part ( 1 ). 37. Headbox according to claim 36, characterized in that the inlet plate ( 11 ) forms part of the inlet part ( 2 ). 38. Headbox according to claim 36 or 37, characterized in that the inlet plate ( 11 ) extends beyond the height of the inlet part ( 2 ). 39. Headbox according to one of the preceding claims, characterized in that at least one nozzle wall ( 5 ) is mounted on a support part ( 10 ) fastened to the central part ( 1 ) so as to be generally displaceable in the direction of flow. 40. Headbox according to claim 39, characterized in that the nozzle wall ( 5 ) is displaceable via at least one preferably mechanical, hydraulic and/or pneumatic adjusting device ( 48 ) which acts on the support part ( 10 ) and the nozzle wall ( 5 ). 41. Headbox according to claim 40, characterized in that the adjusting device ( 48 ) comprises at least two pivot pins ( 50 ) mounted in the support part ( 10 ), each of which has an eccentric extension ( 51 ) which engages in a groove ( 55 ) provided in the nozzle wall ( 5 ), the pivot pins ( 50 ) preferably carrying levers ( 52 ) with integrated pivotable nuts ( 53 ) which can be actuated via a common adjusting spindle ( 54 ) with opposing threads. 42. Headbox according to claim 41, characterized in that the respective eccentric extension ( 51 ) is detachable from the respective pivot pin ( 50 ). 43. Headbox according to one of the preceding claims, characterized in that the inlet part ( 2 ) is supplied with fiber suspension via individual supply bores ( 18 ) and the supply bores ( 18 ) are connected either to longer individual hoses ( 3 ) or directly to a common distribution pipe ( 19 ) which is arranged essentially parallel to the outlet gap.