PL89042B1 - Continuous press[us3851685a] - Google Patents

Abstract

A continuous press has two rotatively driven endless conveyor belts forming opposed, substantially linear spans defining a pressing zone, press platens applying pressure through these traveling spans to work carried therebetween, and anti-friction means being interposed between the platens and the spans. Such a press is improved in that the anti-friction means is formed by a multiplicity of endless loops of rotatively unpowered roller chains forming a bed interposed between the platens and the belt spans, the roller chain spans extending longitudinally with respect to the belt spans and being transversely packed together, but each chain being individually free to travel independently with respect to the others and to the belt span. [US3851685A]

Description

The subject of the invention is a press for the production of plates, in particular for the continuous production of plates under pressure and optionally under thermal influence, in which the strand is guided between forming belts with a closed circumference, moving in the direction of movement and extending along its entire width, and in which rollers are provided between the forming belts and under and above them, rolling on plates placed in a support structure, running in a longitudinal plane perpendicular to the strand, wherein these rollers transfer the working pressure from the supporting structure to the forming belts. It is known from the United States of America, No. 2,142,932, a press for the production of plates. particleboard, in which the forming strips are formed by a series of flexible steel strips placed transversely to the strip, which rest on a supporting structure by rod-shaped rollers guided on both sides by chains. The rollers have a relatively small diameter and are placed right next to each other so that no undulations occur in the steel strips. The rollers transfer heat from the heated supporting structure to the forming strips located between the strips. A similar construction, but with joints! forming belts is known from the German patent description 923 172. When strips are to be produced in such presses at very high pressure, for example sandwich panels made of heat-cured plastics, difficulties arise with the correct running of the rollers. At high pressure, a particularly small support distance must be maintained at the forming belts due to their flexibility, in order to avoid unacceptable bulges of the forming belt between the individual support points or lines. However, a small support gap when using rollers means a small roller diameter, which results in very long rollers for possible band widths of 2 to 2.5 m. Despite the significantly reduced mutual roller spacing, bends occur between the individual rollers, which, with a roller diameter of 10 to 100 mm and the steel strip thickness of 1 to 1.5 mm, can reach significant dimensions of several hundredths of a millimeter. A slight bend at a specific point on the forming belt will be compensated by moving the forming belt when that point gets under the next roller, but reappears behind the roller. The entire bend is, as it were, shifted along the forming belt. This shifting leads, because it is not a system with ideal elastic properties, to the forces of the bent forming belt acting on the rollers, which absorb them along their entire length and tend to bend the rollers in the rolling plane. Therefore, the rollers in the area between the side chains slightly overtake the chains in the direction of the forming belt movement. Such overtaking also occurs when the forming belts are loaded unevenly across the width of the band. This phenomenon occurs particularly when pressing particleboard, which is pressed from a charge applied to the lower forming belt. Such a charge can never be perfectly uniform, but it does contain zones that, when pressed to a certain height, provide greater resistance than adjacent zones. In zones of higher pressure, the forming belts undergo greater deflection than in adjacent areas. This greater deflection presses the rollers more strongly, and to overcome this deflection during feed, they require greater force, which acts on the rollers and pulls them more strongly in areas of significant pressure than in adjacent areas. This results in a tendency for long, thin rollers to bend in the rolling plane. The bending loads occurring with each rotation of the bent rollers mean significant, permanent deformation of the rollers. It is particularly important, however, that a bent roller has very unfavorable running properties if any section of the roller is not positioned precisely perpendicular to the running direction. The rolling direction of these sections is oblique to the longitudinal direction of the forming belt and the supporting structure. For free rolling, this would mean lateral displacement of the disc relative to the forming belt and the supporting structure, and simultaneously their mutual lateral displacement. This displacement is prevented by guiding the above-mentioned elements in the machine under the action of significant forces. The forming belts and the supporting structure are held in opposite positions, and the rollers are held lateral to the sides between them. The individual discs, into which the roller can theoretically be divided, want to run at specific points diagonally to the strand, but can only move straight. Pure rolling is impossible in this situation. Furthermore, the circumference of the rollers in places where the rollers run properly and in places where the roller axis is oblique is different in length, so that in a given section of the circuit, given places of the rollers move by different angles, that is, they become twisted. The more oblique the roller position in a given place, the higher the speed at that place. This causes the bend, once created, to increase automatically. Due to the presence of forces restoring the roll to its original shape, an equilibrium is created in which the twisting moment caused by the different rotation angles of individual roll locations balances the friction acting on the circumference and prevents further twisting when the roll is moved in specific locations in the circumferential direction relative to the contact surface. This phenomenon leads to significant friction of the rolls, which are not completely straight. Under significant linear pressure, these roll defects play a significant and detrimental role, as the constant friction causes wear to the rolls and belts. Repairing the pressure transfer system in a device of this type is a very difficult undertaking, as the forming belts, rollers, and sometimes even the support surfaces must be replaced. These machines have a working width of 2 to 2.5 m and a length of 10 to 20 m, which practically require partial refurbishment and extended downtime, which naturally applies to the entire production chain. Therefore, reducing component wear is of paramount importance. The friction process described also increases the power requirement for moving the forming belts. A belt resting on properly running rollers can be pulled much more easily than a belt that must overcome the forces of diagonally running rollers. The driving force required to move the forming belt through the pressure area, especially at high operating pressure, is significant and can stress the forming belts to their breaking point. Therefore, improving the running properties of the described system is also of great importance in this respect. Finally, the precision requirements of the produced panels are also important. When the rollers or belts are worn or the tracks in the supporting structure are worn, differences in the thickness of the produced strip can occur, far beyond the permissible tolerance, causing uneven loading of the rollers and correspondingly uneven heat transfer. French patent specification 1469 225 describes a press for the continuous production of panels in which, instead of U-shaped rollers arranged across the entire width of the strip, rollers arranged behind each other transversely to the strip are provided, two adjacent rollers of which are connected by coupling pins. Ladder chains running longitudinally are arranged between adjacent rollers. This arrangement does not differ significantly in operation from the arrangement with rod-shaped rollers. Regarding the forces exerted on the rollers by bending the forming belts, the conditions are essentially identical to those in other known presses. However, the effects of these forces are even more negative in the roller arrangement described in French patent specification 1469 225 than in other solutions, because the rollers are not made in one piece and are not provided with adequate protection against bending, but are weakened at the coupling pins. Therefore, the row of rollers transverse to the belt bends more easily. Furthermore, there is an additional connection by an internal ladder chain. The rollers are connected not only laterally but also to the front and rear rollers, creating a rolling field. As a result, a local bearing fault in one roller is not limited to it, but is transferred through the coupling pins and chain to the adjacent rollers and spreads to the surrounding roller system. Also known from U.S. Patent 3,120,862 is a press in which, to support the forming belts, there are a number of side-by-side rows of cylindrical rollers running parallel to each other. Instead of flexible forming belts, link chains are used here, arranged over the entire width of the band, creating pressure planes, which do not bend between the support points on the rollers and which do not experience any problems with this. To guide the rollers laterally on their tracks, grooves are provided both in the supporting structure and in the link chains, in which the rollers run freely and rest with their front surfaces on the sides of the grooves. In one version, the rollers run directly behind each other, with considerable circumferential friction occurring between the rollers. To reduce this friction, a cage similar to a bearing cage is provided between the rollers, which keeps the rollers at a distance. This necessary distance is not important in the case of flexible link chains according to U.S. Patent No. 3,120,862, but in the case of flexible forming belts, it is very undesirable, especially since it simultaneously reduces the amount of heat. transferred by the rollers per unit area. Cages are also unsuitable because they catch the rollers on the circumference. When the cages transmit longitudinal forces, which, as practice shows, can happen with uneven chain runs, the friction forces cause a correspondingly higher braking torque. Furthermore, the roller circumference and cage naturally wear out, with the higher relative speed on the roller circumference also being of significant importance. The aim of the invention is to create a device in which the uninterrupted running of the support rollers is ensured even at high operating pressure. This aim was achieved by developing a press design that has roller chains installed closely next to each other in its longitudinal section across the entire width of the band, independently moving forward, forming single Segments with rollers with axes transverse to the strand. The narrow roller width eliminates the harmful effects of roller deflection across the entire strand width. The areas where different pressures occur for given strands are larger than the roller length, so they are not subjected to significantly different operating pressures and are therefore not subjected to bending forces. For a strand 2.5 m wide, there should be 50 to 100 roller chains spaced side by side. It is crucial that adjacent roller chains run independently of each other. Slight deviations in the running of one roller chain must not be transferred to adjacent roller chains and disturb their running. If a roller of a roller chain is for some reason subjected to a force that causes it to accelerate slightly, the adjacent rollers of the next roller chain will not be forced to be positioned obliquely, but remain in the correct position, and an accidental failure of another chain will not affect it. By separating the roller system transversely to the track, the above-described inconveniences caused by the rollers being connected along the entire section transverse to the track are eliminated. By arranging the rollers in the chains, it is achieved that the individual rollers of the chain are held in a parallel position to each other and cannot run out to the sides. Roller chains are understood to mean chains in which the individual rollers are mounted on axial journals in Side ladder chains, which have end-punched links running perpendicular to the rolling plane, with the ends of successive links overlapping. Roller chains of this type can be constructed so that the rollers of one chain do not touch each other, but follow each other with the smallest possible distance, which is advantageous in terms of bending of the forming belts and the heat transfer capacity of the system. The chains thus take over the role of grooves and cages, as described in U.S. Patent No. 3120,862. The chains can transfer significant longitudinal forces without causing friction on the circumference of the rollers. The force is transferred over a small radius on the axle journals. rollers. For better heat supply, it is advantageous if the plates constituting the side surface of the rollers on the side subjected to pressure are smooth. The word "smooth" means that the entirety of the running surfaces of the individual roller chains, lying next to each other transversely to the band, forms a toothless surface. Unlike known devices with separately machined grooves, it can be manufactured in one piece with appropriate precision and evenness. The word "smooth" does not mean, however, that the surface must be closed in one part; slots and small holes can be provided in it. Adjacent running surfaces should be machined together to ensure positional accuracy and reduce machining costs. In the first version of the solution, the roller chains can directly border each other along a section This requires a suitable design of the outer limit of the roller chains, which must be free from protrusions to prevent adjacent roller chains from catching and to ensure independent free running. Roller chains can be manufactured as Gall chains with link chains fitted on both sides. These chains are characterized by simplicity and economy, as they are commercially available in many standardized dimensions. This type of chains necessarily creates gaps between adjacent rollers, transverse to the strand, the width of the link, in which the shaped belt is not supported by the rollers. This also occurs in the case of multi-strand chains at the inner point. connectors. These gaps create longitudinally extending strips, unsupported streets. At not very high pressures, these free spaces do not yet lead to disruptions. However, with certain materials, for example, artificial resin laminates, etc., it is important to exert significant pressure as evenly as possible. Furthermore, the rollers of the system in question transfer not only the pressure but also the heat from the heated support structure to the forming belts, and thus to the hardening mass pressed between them. Known chains necessarily provide a strip-like transfer of pressure and heat, which, with certain artificial resin laminates, leads to defective products. In order to ensure uniform transfer, Due to the application of high pressure and heat to the forming belts and the mass between them, the lateral boundaries of the individual strands following each other in the direction of roller travel are displaced transversely to the direction of travel. This means that in the transverse direction there is no part of the strand that remains permanently free of rollers. The intermediate space between laterally adjacent rollers is covered by subsequent rollers, which are displaced relative to the previous roller and reach into this intermediate space. It is not necessary for the immediately following roller to cover the entire free space. This can only happen after several rollers have passed. To ensure the solution of this problem, a roller chain with rollers following each other in the direction of chain travel and parallel to it ¦ the front side of the rollers with connectors, is characterized in that the connectors connecting two consecutive rollers are bent laterally between the rollers. The bent occurs naturally in the rolling plane. The advantage of this solution is that a relatively large lateral displacement of the rollers running directly one after the other can be achieved. However, it should be taken into account that the bent connector element placed between the rollers running one after the other does not allow for direct pressing of the rollers against each other and increases the support distances. Due to the tensile strength of the chain, the bent elements are obviously not advantageous, which is not significant as long as the chain is not pulled, but, as in the continuous press system according to the invention, it only serves to hold rollers. It is advantageous when several successive links, connecting two adjacent rollers, are displaced relative to the preceding link each time in the same direction of the strand, whereby straight links are used primarily. These links form a longitudinal string parallel to the strand, as in conventional roller chains, but within one chain strand they are arranged diagonally as a result of repeated displacement, while the chain as a whole runs straight. In a specific solution, this can be achieved, for example, by the links of one single strand being arranged with a constant displacement in the same direction, and on the side of the single strand from which the links move away by displacement, after several successive A new ladder chain begins on the rollers at the edge of the strand, while on the other side, after a corresponding number of successive rollers, the ladder chain closest to the edge ends. Such a chain comprises a plurality of ladder chains that run parallel to each other, but diagonally to the chain's course. Between these ladder chains, a plurality of rollers are provided inside the individual strands, each separated by a number of ladder chains. The ladder chains slide as a result of constant diagonal displacement on the rolling surface encompassed by a single strand, which, on the other hand, means that the rollers reach every point of this surface. Another solution is that the direction of movement of the ladder chain links is changed after several successive rollers so that the chains The ladder chains run in a zigzag pattern in the individual strand. This avoids breaking and re-hanging the chain. Admittedly, the strand coverage is not completely uniform, because next to the areas that are constantly touched, there are areas that are touched at regular intervals. Purposely, one single strand includes two ladder chains, whose links are each moved in opposite directions. Another feature of this type of chain is the different width of the outer rollers, so that the outer limiting surfaces of the outer rollers of the strand lie in the same plane. This feature allows the parallel limiting of the roller chains to be maintained despite the fact that the strand chains do not run in the longitudinal direction. If, in addition, the outer rollers are supported on one side and the ends of the outer roller journals are embedded in their front surfaces, a configuration is obtained in which the rollers of adjacent strands, i.e. their supporting areas, are in direct contact with each other, the former to the strand. On the outer limits of the strands there are no connectors that would condition the free span of the forming belts. Inside the individual strands, the action of the existing ladder chains is canceled by their diagonal guidance. The independent run of adjacent strands is secured with the simultaneous rolling of the entire pressed surface. To exclude any mutual influence of the roller chains, it is advantageous to place flat roller chains extending in the running direction, standing vertically to the plane of the belts' rolling. The belts between the roller chains cause their complete separation from each other so that the transmission of various longitudinal movements of adjacent roller chains through friction or the catching of protruding edges is excluded. 40 45 50 65 0089042 9 In one version, these belts are permanently arranged in the longitudinal direction on the support structure. The roller chains run along the belt on both sides. To hold the belts, they can be tensioned on tensioners located at the ends of the support structure. Difficulties with the proper running of the roller chains occur where they run under pressure, i.e. between the plates of the support structure and the forming belts. In principle, it is therefore sufficient if the belts are only arranged between the roller chain sections that transfer pressure between the support structure plates and the forming belts. In another embodiment, endless belts run around the drums in a longitudinal plane perpendicular to the web. The belts then run essentially parallel to the roller chains, while at the turning points at the front and rear of the support structure, the belts are rotated 90° to avoid kinking and can be bent with their flat sides. In one embodiment, the belts have a width smaller than the roller diameter and are placed between the plates and the forming belt(s). Belts constructed in this way have no connection to the plates and can move transversely to the web. Their width is calculated so that they fit between the plates and the forming belts, but in each case they cover the area where the projections of adjacent ladder chains may be likely to catch. The belts must be fastened only at the ends protruding from the part of the supporting structure that carries the working pressure. In some cases, even fastening at the rear end, viewed in the direction of travel, is sufficient, because the belts are pulled by the movement of the adjacent ladder chains and held in position. To provide lateral guidance to the entire roller chain system, at least one belt can be run with its longitudinal edge into the longitudinal groove of the plate and protrude from the groove between the chains. The grooves required for the belts are narrow and do not require special accuracy in depth. Because the belts are relatively thin, and with When making very narrow grooves, machining difficulties increase again. It is advantageous to insert an additional insert belt into the groove next to the belt part. The width of the groove then corresponds to the sum of the belt thickness and the insert belt, so that despite the thin belt, the groove has a width that is easy to "make." The belt can be wedged and held in the groove by the insert belt. The belts inserted into the plate do not have to be provided between every other roller chain. A variation deliberately provides for the belts inserted into the plate to occur at intervals of every few roller chains across the width of the band. Since the belts do not transfer significant forces, but are only intended to prevent the edges and protrusions of adjacent roller chains from catching, they do not have to be very stable. They can be made of steel, for example a steel strip of approximately 1 mm thickness, whereby a friction-reducing coating, for example a sprayed-on Teflon layer, can be provided on the flat sides of the steel strip, or they can be made of plastic. Once the roller chains have passed through the pressing area, they must be guided back towards the inlet. On the one hand, this can be achieved by guiding the chains outside the support structure. However, the discharge can also be achieved by placing a pressure transfer plate between the support structure and the associated forming belt, which has grooves arranged longitudinally on the side facing away from the belt, the depth of which is greater than the roller diameter and the width corresponding to width of the chains. The chains run back to the entrance through these grooves, but due to the greater depth of the grooves they do not transmit forces and move unloaded. The transverse spacing of the grooves corresponds to the spacing of the chains. This is equal to the spacing of the ribs remaining between the grooves, which must bear the entire pressure and therefore cannot be arbitrarily narrow, as would be desirable for a small spacing of the individual tendons. In order to be able to arrange the grooves more densely without endangering the load-bearing cross-section of the ribs remaining between the grooves, it is advantageous for the plate to have a thickness greater than twice the diameter of the rollers. When the lateral surfaces of the adjacent grooves, facing each other, lie in the same plane, these The grooves can accommodate chains whose lateral boundary surfaces run adjacent to each other without interruption. Preferably, the support structure comprises a heavy plate containing heating channels and around which rollers rotate in a longitudinal plane perpendicular to the web. To direct the rollers from the lower side of the support structure, which forms the support surface, to its upper side, reversing devices are provided at the ends of the plate. These devices direct the rollers from the side facing the forming belt to the other side of the plate, or vice versa. During prolonged operation of such devices, especially when processing powdered or fine-grained material, it may happen that particles of this material get trapped between the plates and the forming belts. and there contaminates the roller tracks. To reduce this danger as much as possible, it is advantageous to exert a slight pneumatic overpressure in the area where the rollers roll between the supporting structure and the associated forming belt to transmit pressure. This overpressure prevents particles from entering this area, because any existing opening allows flow from the inside to the outside. To maintain this overpressure, the area between the supporting structure and the associated forming belt is covered and tightly connected to the supporting structure by a cover which has seals for sealing against the forming belts, and a compressed air supply. It is advantageous to arrange the circulation closed rollers in a sealed casing, especially with the rollers discharged to the outside around the support structure. The subject of the invention is shown in an example embodiment in the drawing, in which Fig. 1 shows the device according to the invention in a side view; Fig. 2 — a diagram of the device according to Fig. 1 in longitudinal section; Fig. 3 — the device according to Fig. 1 in a slightly enlarged scale in cross-section; Fig. 4 — the edge area of the pressure-transferring plate marked with a dotted frame in Fig. 3 in partial cross-section; Fig. 5 — examples of embodiments in partial cross-section as in Fig. 4; Fig. 6 — a partial longitudinal section of a section of the plate from Fig. 5; Fig. 7 - another embodiment of the invention in partial cross-section as in Fig. 4; Fig. 8 - an example according to Fig. 7, in partial cross-section; Figs. 9 to 11 - exemplary embodiment of roller chains specially suitable for presses according to the invention. Fig. 1 shows a press for the production of particleboards, mineral-bonded building boards, for sintering strips of Teflon Ltp. It comprises an upper forming belt 1 made of steel sheet with a thickness of about 1 to 1.5 mm and an identical lower forming belt 2. Between the forming belts 1, 2, in section 3, a strip 4 is pressed, which is formed from a charge 4' consisting of the above-mentioned materials. The upper The forming belt 1 runs around rollers or drums 5, 6, arranged transversely to the web 4. The drum 6 is mounted in a fixed stand 7, and the drum 5 in a stand 9, which is pivotable around an axis transverse to the web 4, and is mounted in a support 8 on the ground. The stand 9 is moved by a hydraulic cylinder 10, thereby tensioning the forming belt 1. The forming belt 2 runs around drums 11, 12, arranged transversely to the web, of which the drum 11 is mounted in a fixed stand 13, and the drum 12 in a stand 14 running on rails. The stand 14 is moved by a hydraulic cylinder in the longitudinal direction of the web, thereby tensioning the forming belt 2. The forming belts are driven by means of a drum.* The forming belts 1, 2 run through the device in the direction indicated by arrows 16, so that the hopper 4' provided on the right side according to Fig. 1 is drawn into section 3 by a device not shown. The pressed strand 4 which runs out is removed by a device not shown on the left side of the forming belt 2. In section 3, a forming belt 4 is placed inside the forming belt. The upper support structure 17 cooperates with the lower support structure 18 located inside the lower forming belt 2 and presses the areas of the forming belts 1, 2 facing the compressed strip 4 against this strip 4 and presses them flat with great force. The support structures 17, 18 consist of girders 19, 20, respectively, which, lying opposite each other, are arranged above and below the forming belts 1, 2 and strip 4 (fig. 2). Each pair of girders 19, 20 is laterally connected to each other outside the strip so that they form individual force-locked pressure members. The connection is effected, as shown in Figs. 1 and 3, by strong pins 21, which act between the supports 22, 23, which are connected to the end plates 24, 25 of the girders 19, 20. The pins 21 can be motorized. The connection force is exerted by a hydraulic cylinder. The lower girders 20 transmit their force via a pressure pad 56 filled with a hydraulic medium, which ensures uniform pressure across the width of the beam, even when the girders are bent under pressure. Each pair of girders 19 is assigned one pressure pad or a common pad for several girders. Between the girders 19 and the pads 56 and the forming belts 1, 2 there are thick plates 26, 27 which transfer the force exerted by the individual pressure members 19, 20 superficially to the forming belts and which have channels containing heating elements or filled with a heating medium. Between the sides facing each other of the plates 26, 27 and the forming belts 1, 2 there are arranged roller chains on which the forming belts 1, 2 are adjusted relative to the plates 26, 27 and which rotate in the longitudinal vertical plane of the plate 26, 27. The structure of the roller chains is explained in detail in FIGS. 4 to 8. The roller chains transfer both the pressure and the heat of the plates 26, 27 to the forming belts 1, 2 and thus to the strand 4. After reaching the end of section 3, the roller chains are directed back to the actual pressing area, i.e. between the girders 19, 20 and the plates 26, 27, as shown in Fig. 2. However, it is also possible to route the roller chains outwards, around the supporting structure, as shown in Fig. 2 at the supporting structure 18. Several plates, which are designed like plates 26, 27, can also be arranged along section 3. For example, it may be advisable to separate the forming area an inclined entry 57 of plate 26' at point 28 from the left-hand part of plate 26 according to Fig. 2 and provide two sets of roller chains which run separately around plate 26 and plate 26'. Fig. 4 shows a first embodiment of the plates 26, 27 and the associated arrangement of roller chains. In this embodiment, a plate 30 is provided which has a smooth lower surface 32. The surface 32 is not divided by ribs or the like and can be easily machined. The surface 32 forms a common track for the roller chains 33 arranged next to each other. The roller chains 33 consist of individual, immediately successive, parallel rollers 34, which are connected to each other by links 35 and axial journals 36, perpendicular to the rolling plane and running in the rolling direction. The journals 36 form both the running axle 40 45 50 55 60 13 of the roller 34 and the articulated mounting of the link 35. The roller chains 33 each form individual strands 58. The adjacent strands 58 (which may run independently of each other, for this purpose in this case) The outer sides of the links 35 are smooth, and the heads of the pins 36 are countersunk. The entire chain 33 forms a rolling surface which has no strength in the running direction and in which no forces can occur that would lead to the individual rollers 34 being distorted. In the shown version, the rollers 34 have a diameter of 12.7 mm. Channels 40 run transversely through the plate, which are connected at their ends to sealed supply lines 41 and supply the plate 30 with heat which is necessary for hardening the mass constituting the strip 4. To avoid heat losses between the upper side of the plate 30, i.e. the one facing the support structure 17 or 18, and the side facing this side, A thermally insulating intermediate plate 42 is placed between the girder 19 or 20. The solution according to Figs. 5 and 6 differs from the solution according to Fig. 4 in that belts 100 are placed between the individual roller chains 3a, which in this solution are made of a steel strip of about 1 mm thickness and a width slightly smaller than the diameter of the rollers 34. The belts 100, arranged with a narrow edge vertically, extend between every two roller chains 33 along the entire section 3. The belts 100 are held at their ends by tensioners 101, shown schematically in Fig. 6, provided outside the plate 30. Particularly strong tensioning The belts 100 are not required. It is only necessary to prevent the belts from being caught by the circulating roller chains 33. The belts 100 are enclosed between the smooth surface 32 of the plate 30 and the forming belt 1. The belts 100 serve to separate adjacent roller chains 33 and prevent the heads 39 and the edges of the links 35 from catching. Fig. 6 shows the ends of the plate 30, which are provided with elements 37 which direct the roller chains 33 away from the surface 32 so that they can be led over the support structure to the other end of the plate 30, and in this way the roller chains 33 run along the plate. 30 and a supporting structure. The elements 37 are wedged by springs 38 at the ends of the plate 30. Figs. 7 and 8 show another arrangement of the plates 26, 27 with roller chains. Here, the plate 26, 27 consists of a heating and support plate 43 and a separated return plate 44. The plate 43 has heating channels which are connected in closed channels by pipes 45. Between the lower side of the plate 43 and the forming belt 1, roller chains 60 run, which on both sides of the chain composed of connectors 35 have rollers 34 in which the ends of the journals 3(£) are inserted. Guide strips are arranged on the lateral boundaries of the plate 43. The roller chains 60 form individual strands 58 which can run independently of each other. Between the roller chains 60 are arranged belts 100 which separate the roller chains 60 from each other and prevent the edges of the rollers 34 from catching. In the version according to Fig. 7, three belts 100 are provided which are arranged freely between the underside of the plate 43 and the forming belt 1. According to Fig. 7, the fourth belt 100', seen from the left, is inserted into the longitudinal groove 102 of the plate 43 and forms a lateral guide which is positioned and fixed with respect to the plate 43, while the free belts 100 can can be moved relative to the plate 43. The groove 102 is cut in the longitudinal direction of the plate 43. It can have a width corresponding to the belt 100' and the belt 100' is inserted directly without an insert. To make the groove easier to produce, the groove is wider than the belt 102 and next to the belt 100' an insert 103 is wedged in the groove 102, which holds the belt 100 in the groove 102. Fig. 8 shows the entry of section 3. The roller chains move in the direction of arrow 104. In this running direction, it is sufficient to place a tensioner at the right end of the belt 100 according to Fig. 8. At the left end of the plate according to Fig. 8, a tensioner 101 is not necessary, because the chain of rollers 60 takes the belt 100 and, moreover, the belt 100 is held between the lower side of the plate 43 and the upper side of the forming belt 1. While in the solution according to Figs. 5 and 6 the return of the roller chains 33 takes place outside the structure 17, 18, according to Figs. 7 and 8 this takes place via special return plates 44 which are arranged between the support structure 17, 18 and the plates 43. The return plates 44 are more than twice as thick as the diameter of the rollers of the roller chain 60. On the side facing the girders 19 or 20, the return plate 44 has return grooves 47 and on the side facing the upper side of the plate 43, grooves The grooves 47, 48 are displaced with respect to each other transversely to the strip 40 so that the lateral limiting surfaces 49, 50 lie essentially vertically above each other. In this way, the corresponding limiting surfaces of adjacent roller chains also run almost in one plane, i.e., displaced only by the width of the strips 100, 100'. The force generating the working pressure is transmitted through the intermediate regions 51, which exist because the thickness of the plate 44 is greater than twice the diameter of the rollers. Elements 52 are also arranged at the ends of this plate, which direct the roller chains 60 from the lower side of the plate to its upper side or in the opposite direction. Elements 52 have different turning radii for adjacent roller chains, so that the roller chains 60 can reach the grooves 47, 48 located at different heights in the plate 44. In the version according to Figs. 7 and 8, a slight pneumatic overpressure is maintained in the rolling area of the roller chains 60, in order to prevent dust from accumulating in this area. For this purpose, a cover 53 is provided between the supporting structure, i.e. the girders 19, and the forming belt 1, which is tightly connected to the supporting structure and sealed against the circulating forming belt 1 by a seal 54. The closed space thus created is supplied with compressed air by a supply 55. It is important for the solutions discussed that two adjacent chains 33 or 60 move independently of each other. The entire supporting element creates a field that is divided in the longitudinal direction by the individual strings 58, which, under appropriate load, can move relative to each other in the longitudinal direction. Therefore, in the roller chain system, forced forces resulting from uneven absorption by the shaped belts cannot be created. There are cases in which very high pressure must be very evenly distributed and at the same time the temperature differences must be small. In this case, the chain system according to Figs. 4 and 5 does not lead to the correct results. Therefore, other types of chains have been developed in which there is no 9. The chain 70 has kinked links 71 and rollers 72, 73 of different lengths, which are arranged alternately according to the kink, so that the outer parallel stop surfaces 74, 75 run parallel. The spaces 76 between the rollers, which include the links, are laterally displaced relative to each other by the kink of the links 71. The space 76 between the upper rollers 72, 73 is covered by the next roller 72 when the chain 70 moves upwards. Since adjacent chains 70 can be in direct contact because of the parallel stop surfaces 74 and 75, the entire pressure surface of the shaped belts 1, 2 is covered by such a chain arrangement. Another solution is shown in Fig. 10 in the form of a chain 80 which has straight links 81. However, these links are not arranged in one line running parallel to the running direction, but several successive links are moved in the same direction. For example, link 81* in Fig. 10 is moved upwards with respect to link 81. Link 81b is again moved upwards with respect to link 81a. Link 81c is moved downwards with respect to link 81b, and the next four links are also moved downwards, up to link 81d, from which upward movement begins again. The entire chain of links 81, 81a etc. runs in a zigzag pattern in the chain 80 so that the space left by the two rollers is covered by one of the following rollers. To the connecting rod 81 is assigned a connecting rod 82, the connecting rods of which are displaced oppositely with respect to the central longitudinal plane of the chain 81 than the connecting rods of the chain 81. Each chain link 80 consists of three rollers, the width of which changes periodically and generally completes a chain with parallel limiting planes 83, 84. The three rollers of one link are held by a pin 85, the head 86 of which is placed in a recess 87 and does not extends beyond the limiting planes 83, 84. Chain 80 corresponds to the chain shown in Figs. 6 and 7. Adjacent chains 80 touch each other with their end surfaces 83, 84, so that no gap remains at these places. The gaps between the individual pulleys of the chain links are covered successively by the following chain rollers, so that a uniform load is obtained on the pressure surface or forming belts 1, 2. Fig. 11 shows another chain solution. Chain 90 is constructed similarly to chain 80, with the difference that the links 91a, 91b, 91c are always moved in the same direction relative to the previous link. The links of the links therefore run diagonally to The parallelism of the end surfaces 97, 99 is achieved by appropriately gradating the lengths of the individual rollers. After a certain number of rollers, the upper connecting rod 91 approaches the edge so that the corresponding roller is very narrow. At this point, the connecting rod 91 is interrupted and a wide roller 93 is added, which has the width of both preceding rollers 92 and 92' and connects to the next chain rod 96. At the lower edge of the chain 90, as shown in Fig. 11, the connecting rod 96 has meanwhile moved away from the lateral limit of the chain 90, whereby the roller 92" lying one member in front of the roller 92 has a length corresponding to that of the roller 93. With the roller 92" only two rollers 93' and 93", between which a new chain strand 98 starts. On the other side, roller 93' is joined. A jump has therefore occurred, at which the previous chain strands 91 and 96 are replaced by strands 96 and 98. Due to the shape of the lateral limits of the rollers, chain 90 corresponds to chain 80. In all chains 70, 80, 90 the outer rollers are arranged on one side in the links of the ladder chains, which enables direct contact of adjacent strands. A press for the production of plates with the described chains is an advantageous embodiment of the invention for cases in which, especially on a uniform surface, rolling or heat transfer. PL PL PL PL PL PL PL PL PL PL

Claims (1)

1.