MXPA99002228A - Under felt inclined flat former to produce multilayer or monolayer sheet of paper - Google Patents

Abstract

An under felt inclined flat former for making multilayer or monolayer sheets of paper comprising a plurality of forming units arranged along a production line. Each of the forming units is supported on corresponding rigid supports and is provided with a roller system on which the forming unit or a portion thereof rests which when the supports are removed, the selected forming unit or portion thereof can be removed from the production line for cleaning or maintenance purposes, without interrupting the operation of the former equipment. Each forming unit including means to create activity in the stock in addition to causing liquid to be drained therefrom for sheet formation.

Description

FLAT, INCLINED FORMER. UNDER THE FELT, TO PRODUCE PAPER SHEET OF MULTIPLE LAYERS OR OF MONOCOP FIELD OF THE INVENTION The equipment of the present invention serves to form a sheet of paper under the felt line or in a papermaking factory, this sheet can be monolayer or multi-layer paper. The sheet of paper formed in this way has characteristics superior to that of a sheet manufactured in a fourdrinier manufacturing table.

BRIEF DESCRIPTION OF THE INVENTION The fiber suspension is distributed through a headbox on a training table, which allows the fiber to be oriented freely according to the speed of jet / fabric and with the hydraulic pattern generated by an activity lip. deformation. The effect generated by the activity lip supplemented in a first embodiment with a pulse-forming roller or allowing the fibers to be oriented freely or in a controlled manner, according to the speed of the roller. The water remaining in the fiber suspension is drained in a box divided into three vacuum compartments, to achieve a fixed drying to make contact with a previous unit of sheet or with the felt in the case of being the first unit. The equipment comprises a forming table in which the inclination can be adjusted according to the manufacturing requirements. This forming table comprises a fabric for forming the sheet of paper, a front roll that also serves as a fabric tensioner, forming dehydrated sheets, a pulse forming roller, flat boxes, a supporting roll or mold, a guide roller and elements control, support structures to support the previous equipment, water collection trays of the head box and rails and rollers for maintenance of the previous equipment, to allow the unit to be removed from services and stop production. The equipment also comprises a fiber distribution head box facing the training table, as well as a suction slider to extract water from the inside of the felt. It is also provided with a rubber deposition roller which presses the felt and the sheet so that the sheet of paper adheres to the felt and can be transferred to the next forming unit. The deposition roller is provided with a mechanism for adjusting the position against the cylinder mold, as well as with a bellows system for lifting the deposition roller or for applying pressure against the cylinder mold. The equipment includes showers to keep the support roller, the fabric and the previous roller clean. A doctor blade is located on the anterior roller to keep the roller clean and to divert water drained in this area to a tray. This unit has a system comprising two vertical structures and a longitudinal beam to provide rigidity thereto. In a second embodiment, the forming table is essentially the same as that described, except that there are drainage blades replacing the flat boxes which allows the drainage and formation of activity. This eliminates the use of a pulse-forming roller among other advantages that will be discussed. In addition, a variation is provided in the head box which has a means for adjusting the position of a modified upper activity lip with respect to the fabric. Other differences in the two modalities will be readily apparent from the discussion in this document.

BACKGROUND OF THE INVENTION Currently there are several types of multi-layer paper forming equipment among which the following can be mentioned: CYLINDER MACHINE, this machine forms the paper sheet by draining the water through a mesh screen attached to a cylinder. The formed sheet is transferred directly to a felt for additional bonding of the next layer. In this machine there is no control over the fiber orientation or the drainage speed of the fiber suspension. FLAT FORMATORS ON FIELTRO LINE, these shapers have a flat table in the paper sheet forming area, when a sheet of paper is formed, and they are transferred to a felt that completely surrounds the felt felt to later pass under this training unit and reach the next training unit. Most of the prior art equipment has several disadvantages such as: inadequate formation, non-adjustable MD / CD tension ratio, tendency to wrinkle with the paper spread in sheets, non-uniform CD profile (flutes), inactivity and limitations of speed, among others. The present invention is designed to solve the defects of the devices of the prior art, and has the additional advantages, since it allows the control of the orientation of the fiber in the previous equipment under the felt line. It also allows to stop a training unit and the complete or partial removal of it from the production line without inactivating the production process. Certain devices of the prior art should be mentioned. In PCT application O95 / 30048 a tilted former is shown, under the felt, to produce a sheet of paper. Drainage is provided by a vacuum box. A separate activity generating device element 82 is used. There is no description of providing an element which provides both functions, ie drainage and activity. In U.S. Patent No. 4,789,433, only one blade is described to form microturbulence of the fiber suspension. Regarding the North American patent No. 4,472,244, is directed to the conversion of a single wire construction into a double wire construction.

BRIEF DESCRIPTION OF THE DRAWINGS Therefore, by means of the present invention, these advantages will be apparent with respect to the prior art, and the description should be considered in conjunction with the drawings, in which: Figure 1 is an elevational view of the paper former showing all its constituents; Figure 2 is a detail of the deposition roller with all the mechanisms thereof; Figure 3 shows a detail of the previous roller, the forming blade and the box head, also with all its components; Figures 4a, 4b and 4c illustrate the activity lip, as well as all components thereof; Figure 5 illustrates the water collection trays and the showers that are part of the training unit; Figure 6 illustrates a side view of the forming roller; Figure 7 illustrates a detail of the formation roll gap; 8 is an elevational view of the forming of paper incorporating the drainage and forming blades and head box along with all other constituents thereof, - figure 9 is an enlarged elevation of the drain and the blades forming machines together with the head box, shown in Figure 8; Figure 10 is an enlarged sectional view of the drainage and forming blade shown in Figure 8; Figure 11 is an enlarged sectional view of the head box shown in Figure 8; Figures 12A, 12B and 12C illustrate the activity lip, as well as the components thereof, Figure 13 illustrates the activity lip on the box head, and Figure 14 is a partially sectioned perspective view of the box. of head shown in figure 8.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES With reference to the embodiment shown in Figures 1-7, the equipment of the present invention comprises a vertical frame (1) anchored in its lower part by screws (4) and also comprises a second frame (3) anchored in the lower part to the floor by screws (7). A beam (2) is located at the top of both frames, joining both frames by means of screws (5) and (6). A mechanism for applying pressure or raising the deposition roller (25) is located on the second frame and on the exit side of the paper sheet. This mechanism comprises two supports (8) and (9), each of them has bellows (10) and (11) corresponding rubber tires, attached thereto. As can be seen in figure 2, the upper pneumatic bellows (10) are joined to the upper part of the support (8) by screws (14) and to the lower part to an arm (12) which is attached to the deposition roller by half of screws (15). The upper bellows (10) have the function of lifting the deposition roller. The lower pneumatic bellows (11) are attached at the bottom to the support (9) by means of screws (17), and at the top are joined to the arm (12) by means of screws (16). A support (13) is attached to the frame (3). The support (13) carries a bearing (30) in its central portion; the bearing houses a pin (31) acting as a fulcrum for the arm (12) which holds the roll deposition by means of a support (18) which in turn is attached to a block (19) support via of the screws (20). The support block (19) has a threaded hole in the central part thereof. This block adjusts its position by means of a pivot (21) fixed to the arm (12) by means of spacers (28) and (29). The support block (19) is attached to the plain bearing (26) supporting the deposition roller 25 by means of rotary screws (23) and the separation block (22). The rotary screws (23) press the smooth bearing of the deposition screw by means of a nut (24) and rotate by means of a bolt (27) fixed to the block (19). With reference to figure 1, the equipment of the present invention also comprises a suction slider (134) that extracts water from the paper sheet and the felt as it passes between the deposition roll (25) and the support roll (32). Note that of the present invention a cylinder machine is being replaced, the cylinder roller of that machine can advantageously be incorporated in the inclined former, instead of being discarded. In Figure 3, it is shown that this equipment also comprises an anterior roller (97), a forming roller (83), a flat box with three compartments (74), (75) and (76) having high polyethylene covers. corresponding density (77), (78) and (79) in its upper part. It also has a cylinder or support mold or roller (32) and a first cloth roll (51), as well as forming cloth (72). The flat box with three compartments (74), (75) and (76) is attached to the main structure (35) by means of screws (80) and (81) which in turn allows the alignment and leveling of the box. The flat box has a plate (130) which prevents water drained from the previous equipment (82) to adhere to the inside of the flat box compartments. The cylinder mold (32) rotates on a bearing housed in a plain bearing (33). This plain bearing is joined to a main structure (35) by means of screws (34). The main structure (35) is supported by means of two blocks (37) and (60) which in turn are joined in the bases (39) and (61) of the previous equipment. These bases are joined to the supports (43), (47), (65) and (68) by means of spacer blocks (41), (49), (63) and (70). A removable block (37) is attached to the base (39) and the main structure (35) by means of two rotary screws (36) and (38). A second removable block (60) attached to the structure and support (61) is attached by means of rotary screws (58) and (59). The removable blocks (37) and (60) serve to maintain the complete forming unit in such a way that when it is required to change the forming fabric (72), the blocks are only removed while the whole unit remains cantilevered, the that allows to carry out the adjustment of the new fabric in a minimum time. The support (39), which is located immediately below the support roller, is attached to the bases (43) and (47) by means of spacers (41) and (49) retained by the screws (40) and (50) ). The support (61), which is immediately below the previous roller, is joined to the bases (65) and (68) by means of spacers (63) and (70). These supports are maintained by means of screws (62) and (71). The equipment of the present invention has a system of rollers (45), (46) and (66), which allows the unit to be housed on rails (44) and (67) when the blocks (63) are removed, ( 70), (49) and (41) support position separators. This allows the unit to be completely removed from the machine without stopping production by only pulling the first one away from its operating position. This unit has a system for controlling the position of the forming fabric (72) by means of a guide roller (51). The mechanism for operating this guiding mechanism operates as follows.- the guide roller (51) is supported by a plain bearing (57), this plain bearing is attached to a support plate (56) which is driven by two bellows (54) and (55) adjustment tires; the support plate (56) is held in place by the rollers (52) and (53), such rollers maintain the horizontal and vertical position of the support plate. The adjustment bellows (54) and (55) adjust the position of the guide roller (51) by changing the pneumatic pressure in each of the bellows.

This equipment comprises an anterior roller (82) attached to the main structure (35) by means of screws (101), which is fixed to the plain bearing (83) around which the front roller rotates to the structure. As shown in Figures 6 and 7 the anterior roller is constructed with a core (138) of steel which is coated with a resin (82) whose surface is machined to provide therewith an aerodynamic profile (139), which It allows the generation of a positive pulse at the first contact with the fabric and a negative pulse at the moment when this profile loses contact with the plastic forming fabric. The peripheral speed of the roller is less than that of the forming fabric, which allows the injection of water from the bottom of the fabric towards the upper part where the fiber suspension is, which therefore generates a rearrangement of the fibers. The previous roller (97), shown in figure 3, rotates on the bearings located in a plain bearing (98), which is joined to the main structure (35) by means of screw (99) and (100). The adjustment of the position of the previous roller is carried out with a pivot (91) by means of nuts (95) and (96). The pivot (91) is attached to a structure (88) which also supports the base of the forming blades (86). The base is attached to the structure (88) by means of a screw (87). The position of the base of the forming blades against the previous rollers is adjusted by means of a pivot (92) and lock nuts (93) and (94). The structure (8) is attached to the main structure (35) by means of screws (89) and (90), the structure of the forming blades retains the forming blade (84) by means of sliders (85) in shape of T. A plastic blade (103) is provided to keep the former roller (97) clean, the plastic blade (103) plays a cleaning paper and at the same time diverts the water drained by the previous roller, towards a tray (128). ) of collection. As shown in Figure 3, the forming equipment comprises a flow box head which comprises a conical manifold (121) whose function is to evenly distribute the flow of the fiber suspension in a direction across the width of the unit. training. Attached to this conical manifold by means of a throat (117), there is a stepped diffuser (114) which is sealed at the lower and upper part by means of a plastic tube (118) .To avoid bending of the stepped diffuser, it is provides a plate (115) that completely covers the diffuser.The plate (115) is attached to the manifold and to the top of the headbox by screws (119) and (120) .The main role of the stepped diffuser is to maintain the fibers in a state of complete dispersion.

As illustrated in Figures 4A, 4B and 4C, the head box has a lower lip (109) and a lip (108) of higher activity. The upper lip positions its open position to control the discharge flow by means of screws (122) located at the ends of the head box. The profile of the box is adjusted by means of the screws (104) located on the inside of the head box, in both cases the screws are adjusted by means of lock nuts (106) and (104). Internal (104) and external (122) screws are attached to a bridge (105) which allows uniform movement of the lip. As illustrated in Figure 3, at the opposite end, the upper activity lip (108) has a universal joint (110) supported on a plate (112) and a retainer unit (111). This allows the upper activity lip (108) to move freely without leakage of fiber suspension. The upper activity discharge end has a profile designed to generate activity in the fiber suspension and which is capable of orienting the high concentration of fibers; It also allows to obtain a lower density paper. The profile consists of a part (136) inclined and a part (135) straight, which produce a change in the flow velocity of the fiber suspension, both horizontally and vertically. The activity profile is separated across the width of the head box by means of sectors (137), (illustrated in Figure 4B), which maintain the same thickness of the upper activity lip. The upper activity lip internally generates a hydraulic pattern and produces transverse fluxes on the formation table at the moment when the fiber suspension leaves the box head. This causes the fiber orientation to be transversely improved, that is, the fiber orientation ratio in the machine direction decreases with respect to the transverse orientation of the fiber. In this way, the values of the physical properties of paper in the transverse direction tend to be similar to those obtained in the machine direction. As shown in Figure 5, a shower (131) keeps the cylinder mold (32) clean. There is also a second shower (132) to keep the guide roller (51) clean.

The forming fabric (72) is kept clean by means of a high pressure shower (133). To collect the water drained in the unit there are a series of trays (127), (128), (12'9) and (126) that collect such water and that drive it to an independent tank. Returning now to the embodiment of the invention shown in FIGS. 8 to 13, parts similar to those previously described have been numbered in a similar manner and are distinguished by a quote. The frame is essentially the same, with a second single member (150) which is replaced by the composite member (3). The beam (2 ') supports the suction slider (134') by means of an adjustable support member (151) which can be configured in any manner suitable for the purposes. The deposition roll (25 ') is supported by the frame (150) in a manner as described above. A support roll or cylinder (32 ') supported by a base (152) is provided. Different from the previous embodiment, a main structure (153) is provided which is fixedly mounted and coupled to the base (152) by means of a removable beam (154). The support roller (32 ') and the base (152) can be pulled away from the forming unit by removing the spacer blocks (41' and 49 ') and the beam (154) to provide service, replacement or for any other reason why it is necessary to do this. The main structure (153) includes a leg (155) that extends downwards and a horizontal frame (156) which is coupled to a base (157) which supports the front roller (97 '). The leg (155) and the base (157) are fixedly mounted by means of the bolts (158, 159, 160, 161). The blocks (37 ', 162, 60') which are then removed, allow the forming fabric (72 ') to be replaced. Of course, when such blocks are removed, the supporting elements must be held in position by means of a cantilevered means temporarily placed on both sides of the machine (i.e., the sides facing in or out of the figure). 8).

As you can see in figures 8 and 9, in this mode, the flat boxes have been removed. A series of drainage / activity blades (167 and 168) have been provided which are placed in respective suction boxes (169 and 170) 5, which are supported by the horizontal frame (156) on a reservoir (171) of collection also supported by the frame (156). The blades (167 and 168) provide activity to, and also drainage of the blade. Figures 10A and 10B show one more representation detailed of one of the blades or the board (167) activity trainer. In this regard, the blade comprises a blade (172) primary and a rear blade (173). The primary blade (172) may include an insert (174) at its leading edge or contact area (175) which can be made of material ceramic or wear resistant, or other suitable material. The leading edge (175) provides a support surface for the forming fabric (72 ') and is essentially planar horizontal with respect thereto. The rear part of the edge (175), the surface of the blade along the line (176) diverges from the fabric (72 ') at an angle of approximately 2 °. The leading edge (175) is followed by a series of raised, regularly formed areas (177) and recesses (178) that start at a distance (179) away from them. In the blade (167) as shown, the raised areas are approximately 38 mm (1.5") to each other Based on the speed of the machine, recesses (178) can be larger or smaller to provide the desired backflow amount, while maintaining laminar flow. it is provided with an upper surface (180) which is inclined downward away from the fabric (72 ') approximately at an angle of 2. The whole of the blade (167), for example, is approximately 42.9 cm (16 7/8") long with a rear blade (173) of approximately 9.8 cm (3 7/8"). The primary blade (172) has a surface of approximately 33 cm (13") adjacent to the fabric (72 ') formed between the primary blade (172) and the rear blade (173) is a space (181) which in its midpoint is approximately 4.8 mm (3/16") across. Several conventional T-mounts (181) are provided for slidably mounting the blade (167) on the suction box (169). This space (181) provides drainage of liquid from the fabric (72 ') and remains flooded during operation along with the space (183) between the primary blade (167) and the web (72'). This will allow a transfer of water from liquid to liquid from the fabric (72 '). The dimensions mentioned above and the angles, although desirable, are not critical. The space size (181) can be adjusted based on the speed of the machine, the consistency of the pulp, the retention of the pulp and the quality of the pulp to obtain the desired amount of drainage. By using a narrow space between the blades, drainage induced by a given drainage force is maximized by insulating the underside of the fabric from the air by flooding the space between the fabric and the blade. The main factor which determines the amount of water drained from the leaf is the size of the space. When using small spaces, the amount of drained water is not affected relatively by the shape of the blade or by the vacuum level of the box. Although a laminar flow is maintained on the curved surface of the blade which induces a vertical flow velocity (ie, upward through the cloth and the pulp) which is beneficial for the formation. The geometry of the blade to provide this, while remaining close to a laminar flow, can be determined and defined by the principles and flow equations of known fluid on thin foils and as set forth in the publication "Theory of ing Sections." by Ira H. Abbott and Albert E. Von Doenltoff published by Dover Publications, Inc., (which includes, in particular, pages 110-115), and "Incompressible Aerodynamics" edited by Bryan Thwaites and published by Dover Publications, Incl., (which includes particularly pages 42-56).

Figure 10B generally illustrates the expected flow pattern of the fluid drained from the stock (184) of material on the fabric (72 '). The arrows (185) show the flow of liquid. As can be seen, a partial flow of liquid is caused to flow back through the fabric (72 ') into the pulp (184) which causes activity and dispersion of the fibers (186) constituting the pulp ( 184). The blades can operate without the presence of external vacuum, or with limited vacuum as a primer during startup. A controlled vacuum can be provided to the boxes (169) and (170) suction. In the illustration in figure 9, the boxes (169) and (170) Suction with the blades follow the roller (97 ') above and operate on the fabric (72') not horizontal or inclined. The construction of the blade (168) is the same as that of the blade (167). Note that the opposite ends of the blades (167) and (168) in the CD direction are "sealed with mold frames and the upper surface at the ends is flat." The blade (167) acting in its double capacity (ie , drainage and activity) is able to remove approximately 65-80% of the water in the pulp without sealing the blade The second blade (168) removes a small amount of water, which leaves the water necessary to provide a bond of improved sheets of sheets formed by successive units, if used.

After passing over the blades (167 and 168), the blade moves until it reaches the constriction between the deposition roll (25 ') and the support mold (32'). At this point, the sheet is transferred to the underside of the fabric (73 ') of the horizontal papermaking machine. The sheet afterwards can be moved to another unit or to a series of forming units with wire in the lower part similarly constructed where additionally formed sheets are attached to it. Returning now to Figures 11 to 13, an alternative flow box head (164) is shown. The box head (164) evenly distributes a stream of pulp or fiber suspension through the CD address of the forming unit. A throat portion (117 ') is provided into which pulp is fed through the inlet (187) Positioned in the throat portion (117 ') is an enhanced trapezoidal shaped blade (202), made primarily of a plastic material slidably held on the T-shaped blade retainers (189). The portion (117') runs through the length of the head box (164) in the direction CD and serves to reduce the turbulence of the pulp passing through it. Coupled to the throat portion (117 ') is a stage diffuser (188). The box head (164) has a lower lip (109 ') and a lip (189) of higher activity. The upper lip (189) is coupled to a support member (190) which rotates around the bearing (191) supported by the member (192) which is mounted to the lip (189). A plurality of adjustment devices (204) are coupled to the support member (205) which is fixedly attached via the members (206) to the lip (189) and placed at spaced intervals along the CD direction of the part. back of the lip (189) to allow or flex or rotate the lip (189) around the bearing (191) by the individual adjustment thereof. The lip (189) is attached to each end to an adjustment mechanism (193) (only one of the two is shown) which is coupled thereto by means of an articulation device (194) to the member (205) of support. This allows the position of the entire lip (189) of activity to be adjusted relative to the lower lip (109) by pivoting it around the pivot point (203). By adjusting the distance between them, the discharge flow is controlled and affected. The activity lip (189) is also coupled to the support (190) by means of retaining nuts (196). As with the previous embodiment, and as shown now in Figures 2A-12C and 13, the upper activity lip (189) has a profile designed to create activity in the fiber suspension and which is capable of creating turbulence to avoid a high concentration of fibers; It also allows to obtain a lower density paper. This profile comprises an inclined portion (197) and a straight portion (198) adjacent to the inclined portions (199 and 200) and to the straight portion (201). This causes a change in velocity (an increased space causes less speed, and a decreased space causes greater velocity) in the flow of the fiber suspension, both horizontally and vertically together with the flow in the CD direction. The activity profile is separated across the box head by means of the sectors (137 ') separated, for example, by approximately 13 mm (0.5") with a depth of approximately 5.1 mm (0.2") which maintains the same thickness of the upper activity lip. The upper activity lip internally generates a hydraulic pattern and produces transverse fluxes on the formation table at the moment when the fiber suspension leaves the box head. This causes the fiber orientation to be transversely improved, that is, the ratio of fiber orientation in the machine direction to the cross fiber orientation decreases. In this way, the values of the physical properties of the paper in the transverse direction tend to be similar to those obtained in the direction of the machine. The head box (164) allows the pulp to be distributed without affecting the base weight profile due to speed or grade change. The lip (189) of activity generates activity and avoids the appearance with striae of the leaf. The use of the blades (167 and 168) in combination with the head box (164) causes a freezing formation on the sheet and prevents back rolling with unrestrained drainage. Note also that the angle between the fabric of the papermaking part (73 ') and the fabric (72') in the first embodiment is approximately 10 °, while in the second embodiment it is approximately 5o. The lower angle allows an increased speed of the fabric. Therefore, by virtue of the present invention, its advantages can be realized and, although the preferred embodiments have been presented and described in detail herein, their scope should not be limited by them, rather, their scope should be determined by that of the appended claims.

Claims (10)

1. A shaper inclined under the felt, in a papermaking machine, the shaper is characterized in that it comprises: a front roll; a support roller downstream of the previous roller; a forming fabric; a drainage means placed between the anterior roller and the support roller for draining liquid from the forming fabric; the anterior roller, the support roller, the forming fabric and the drainage medium are placed under the paper forming felt in a paper forming machine, the forming fabric engages the anterior roller and the supporting roller in an endless circuit and they pass over the middle drainage which removes liquid from the pulp on the forming fabric and a medium of activity which generates activity in the pulp; the draining means includes a means of activity which drives a portion of the liquid drained back through the fabric to cause activity in the pulp therein while allowing drainage of liquid therefrom; a deposition roller positioned above the paper-forming felt and above the support roll to cause the paper-forming felt to engage the forming fabric so as to allow the transfer of a sheet formed on the forming fabric to the forming felt of paper; the draining means and the forming fabric are inclined with respect to the paper forming felt; a box head placed at the beginning of the forming fabric for placing the pulp thereon; and wherein the pulp is introduced on the forming fabric by the box head, which, due to the rotation of the anterior roller and the support roller, causes the forming fabric to pass over the drainage means, which causes activity. in the pulp and liquid is drained from the pulp into a sheet which is then transferred to the paper-forming felt at the joint formed between the deposition roll and the support roll.

2. The planar shaper, inclined, under the felt, according to claim 1, characterized in that the activity medium comprises at least one activity-forming blade.

3. The planar shaper, inclined, under the felt, according to claim 2, characterized in that it also comprises an inductor activity agent located in the box head to induce activity and dispersion of pulp before it flows on the forming fabric.

4. The planar shaper, inclined, under the felt, according to claim 2, characterized in that the support roller is a cylinder mold.

5. The flat conformer, inclined, under the felt, according to claim 2, characterized in that the head box comprises a stepped diffuser which keeps the pulp in a dispersed state.

6. The planar shaper, inclined, under the felt, according to claim 3, characterized in that the activity inducing means comprises an upper activity lip located in the box head to create activity in the pulp as it is fed onto the training.

7. The flat, inclined shaper, under the felt, according to claim 2, characterized in that the shaper includes a support means for supporting the shaper under a paper-forming felt and including a means for pulling the support roller away from the shaper. bottom part of a paper-forming felt without stopping production therein.

8. The flat, inclined shaper, under the felt, according to claim 2, characterized in that it includes a plurality of inclined shapers under the felt which are placed in series and used in the sheet formation.

9. The planar shaper, inclined, under the felt, according to claim, characterized in that the inclination angle of the former is about 5 to 10 ° with respect to the paper-forming fabric.

10. The planar shaper, inclined, under the felt, according to claim 6, characterized in that the activity lip causes a variation of the flow velocity as the pulp flows in a machine direction.