FR2942870A1 - TUNNEL DRYER FOR BUILDING PRODUCTS SUCH AS BRICKS OR TILES - Google Patents

Abstract

Dryer comprising a lower tunnel (110) and an upper tunnel (120) connected at each end by a well (130, 140) traversed by a chain conveyor (150) with pods (155) receiving products to be dried. The chain (150) passes from a horizontal path to a vertical path (or vice versa) at the junction (151) of a tunnel (110, 120) or a shaft (130, 140) by a bevel gear (151-154) and at the well (130, 140), the return pulley (151A-154A) at the end of the horizontal path is completed by a deflection pulley (151B-154B) installed in the well (130 , 140) so that the chain (150) follows an inclined path corresponding substantially to the hypotenuse of the triangle taken in the rectangle whose vertical side is equal to the height of the nacelle (155) to its point of suspension at the chain (150) and the horizontal side is equal to the half-width of the nacelle (155).

Description

FIELD OF THE INVENTION The present invention relates to a tunnel dryer for building products such as bricks or tiles comprising a lower tunnel and an upper tunnel, connected at each end by a well, forming a circulation path consisting of the succession of the lower tunnel, a well, the upper tunnel and a well, this loop path being traversed by a chain conveyor to which are suspended pods receiving products to be dried, - the chain passing a path horizontal at a vertical (or vice versa) path at the junction of a tunnel or well by a bevel gear, - the nacelles being separated from the minimum gap necessary to prevent the collision of two nacelles successive at the junction of the horizontal path and the vertical path (or vice versa), the chain passing on a pulley at each junction, the nacelles generally have a rectangular section with a pole Fixing to the chain in the middle of their width. STATE OF THE ART Such tunnel dryers (s) composed in fact of two superimposed tunnels, are known and are used for the manufacture of building products such as bricks or tiles. These tunnels have a production capacity depending on the number of places available in the nacelle inside the tunnels for the products to be dried. This means that for the same length of tunnel, the capacity is limited by the number of nacelles that can equip the conveyor chain. However, the nacelles must respect a de-terminated interval between two successive nacelles so that, at the level of the angle references constituted by a pulley, between the exit (or the entry) of a tunnel and the well of descent / rise , two successive nacelles do not collide. It is an object of the present invention to develop a tunnel dryer having a larger production capacity for otherwise identical dimensions or allowing a reduction of dryer dimensions for the same capacity as that of known installations. The invention also proposes to create means for improving the capacity of existing dryers.

2 DESCRIPTION AND ADVANTAGES OF THE INVENTION To this end, the present invention relates to a tunnel dryer of the type defined above characterized in that at each return angle of the rectangular path, at the well, the pulley return at the end of the horizontal path is completed by a deflection pulley installed in the well so that the chain which passes around the deflection pulley and the deflection pulley follows an inclined path substantially corresponding to the hypotenuse of the triangle formed by the rectangle whose vertical side is equal to the height of the nacelle to its suspension point to the chain and the horizontal side is equal to the half-width of the nacelle. The dryer according to the invention allows a very significant increase in capacity of the order of 15 or even 25% by a better occupation of the chain with closer nacelles without creating risk of collision of two successive nacelles at the level of a corner reference. Such an increase in production capacity is also possible by transforming existing tunnel dryers by simply modifying the return pulleys at the inlet or the outlet at both ends of each of the tunnels. This transformation, resulting in only comparatively small investments compared to those of the entire installation, allows an unexpected increase in the plant's production capacity which, as indicated above, will be increased by 15%. at 25% or more. According to another advantageous characteristic, the nacelle comprises a single solid partition to close the airlock of a well connecting the two tunnels. This solution simplifies the implementation of the installation because the nacelles do not necessarily have an upper partition and a lower bulkhead to complete the airlock. Indeed, thanks to the important approximation of nacelles made possible by the invention, the airlock can be closed at the top and bottom only by the presence of a low or high full partition of two successive nacelles since they are sufficiently 35 closer to ensure this seal This simplifies the realization of nacelles, alleviates each na-that and reduces the cost of installation and its cost of operation by reducing the dead weight transported.

According to another advantageous characteristic, the deflection pulley and the deflection pulley are completed by an auxiliary pulley, creating an outward deflection of the chain circulation path which would pass only on the return pulleys and the pulleys. deflection, enough to divert the deflection pulleys well to create an airlock closed by one or two successive nacelles. This solution makes it possible to transform the existing driers and whose height between the lower tunnel and the upper tunnel would not be sufficient so that, once equipped with the corner-bearings according to the invention, there remains a sufficient height at the level of the well. ascent, in the exit station to realize the airlock. The invention also relates to a dryer comprising, for one of the tunnels, at the junction of the wells, a return pulley and a deflection pulley and, for the other tunnel, at each end, a return pulley combined with a deflection pulley and supplemented by an auxiliary pulley creating the outward deviation of the chain circulation path. The invention, in its various characteristics, allows not only the realization and the first installation of reduced space tunnel dryers between the nacelles but also the transformation of existing tunnel dryers to seriously increase the production capacity. Drawings The present invention will be described in more detail with the aid of the accompanying drawings showing two embodiments of a tunnel dryer according to the invention and an embodiment of a tunnel known to allow comparisons. In the drawings: FIG. 1 is a diagrammatic vertical sectional view of a tunnel dryer according to the state of the art, FIG. 2 schematically shows, in its parts A and B respectively, FIG. 2A, the junction of a tunnel and a well at any end of a tunnel of the dryer of FIG. 1, 35 * in FIG. 2B, a diagram similar to that of FIG. 2A of the junction between FIG. a tunnel and a well of a dryer according to the invention, 4 - Figure 3 is a schematic vertical section of a tunnel dryer according to a first embodiment of the invention, - Figure 4 is a sectional view. schematic vertical view of a tunnel dryer according to a second embodiment of the invention, adaptable to existing dryers, - Figure 5 shows schematically the combination of the two solutions of Figures 3 and 4, - Figure 6 is a schematic view. the junction of a tunnel and a well, allowing the calculation of the distance m between the two nacelles 10 of the known installation of FIG. 1, FIG. 7 is a diagram of the junction of a tunnel and a well of the tunnel dryer of FIG. 3, allowing the calculation of the minimum distance. between two nacelles, FIG. 8 is a diagram similar to that of FIG. 7 relating to the junction of a tunnel and a tunnel dryer well of FIG. 4 allowing the calculation of the minimum distance between two nacelles. DESCRIPTION OF EMBODIMENTS OF THE INVENTION Before describing the three embodiments of the invention, by way of comparison reference, a tunnel dryer (s) according to the state of the art will be described below. in its general structure and for the principle of joining a tunnel and a well (Figure 2A). According to FIG. 1, a tunnel dryer (s) 1 intended for drying construction products such as bricks or tiles comprises two horizontal tunnels, a lower tunnel and an upper tunnel, opening at each of their two ends 11, 12; 21, 22 in a vertical shaft 30, 40. The tunnels 10, 20 and the wells 30, 40 are traversed by a chain conveyor 50 passing over four return pulleys 51, 52, 53, 54 at each junction between a tunnel 10, 20 and a well 30, 40, both at the descent into the well and at the bottom end of the well as well as up a well to the entrance in the upper tunnel 20. chain conveyor or to simplify the chain 50, is equipped with nacelles 55 or swings in which the products to be dried are loaded. These nacelles 55 are spaced a minimum distance (d) so as to make the best use of the space available in the dryer (1) to optimize the efficiency. The distance (d, dl) separating two nacelles 55 or their attachment points 56 to the chain 50 is limited to a minimum because of the problem of collision between two successive nacelles at the junction of a tunnel and a well, when the nacelle 55 upstream, down into the well and the downstream nacelle comes from the tunnel, which is also true for a traffic in the opposite direction. This collision problem will be discussed schematically using FIG. 2A. The loading / unloading of the nacelles is done in one of the wells 40 equipped with a loading / unloading station 60. The loading station 60 comprises, in the passage 61 followed by the nacelles 55, a double opening 62, 63 of on both sides of a platform stopped in this position. The loading / unloading of the products are two operations that are done almost simultaneously. The load-ment device, not shown, pushes the products placed on a floor of the nacelle through for example the opening 62 and at the same time, deposits green products, that is to say products to dry , via the opening 63. This nacelle loading technique, known per se, does not require a more detailed description. It should be noted that at the loading / unloading station, the nacelles provide a certain degree of tightness in order to prevent too much outside air being sucked in by the vacuum cleaner 74 of the chimney 75. for the sake of simplicity, the description refers to a chain 50 driving the pods 55, this chain is actually doubled and the pods 55 are attached to the parallel chains 50 which follow the flow path described above. The chains 50 pass on the return pulleys 51-54 which may be toothed pulleys or chain wheels, at least some of which drive the chains. In the example shown, the pulley 54 is a driving pulley.

The nacelles 55 are attached to the chains 50 in the upper part substantially in their middle 56 for reasons of balance and in practice, the attachment points are located slightly below the top of the nacelle. The sides of the nacelles are equipped with unrepresented rollers which circulate in lateral rails to the passage of the nacelles in the lower tunnel 10 and in the upper tunnel 20. On the other hand, in the descent and rise well 30, 40, the Nacelles 55 are only sus-hanged to chains 50.

6 The dryer 1 whose structure is described above, is traversed by the boats 55 which circulate in a certain direction (arrow F) and by hot drying gases circulating against the current (arrow G). Hot gases are provided by equipment 70 consisting of burners and fans that blow hot gases into the lower tunnel 10 near its exit. The hot gases pass through the lower tunnel 10 to exit through a bypass 71 equipped with a vacuum cleaner 72 and bypassing the vertical descent shaft 30 to be injected again in the upper part of the well at the upper tunnel 20 in which the gases also flow against the current. The hot gases circulating in the upper tunnel 20 can be partially recovered at point 73, near the entrance 21 of the tunnel to be recycled through the equipment generating the hot air 70. But the main part of the hot gases The branch 71 is equipped with a fan 72 so as to blow the hot gases from the lower tunnel 10 into the outlet 22 of the upper tunnel 20. But to prevent hot gases thus blown into the upper tunnel 20 from attempting to pass through the well 30 to circulate in a loop, the well comprises an airlock 31 closed by the nacelles 55. This airlock 31 is formed by a cylinder 32 of section rectangular corresponding to the section of the nacelle 55 (width and depth, the depth is the dimension of the nacelle perpendicular to the plane of Figure 1). This cylinder 32 is closed on the sides. Its height is such that at least the bottom wall 55I of a nacelle and the upper wall 55S of the following nacelle are in the cylinder 32, in the closed parts around the entire periphery. To form the cap defining the lock 31, each known unit has an upper wall 55S and a lower wall 55I constituted by a solid plate so that whatever the movement of the pods 55 in the cylinder 32, there will always be a upper wall 55S and a lower wall 55I belonging to the same nacelle or two successive nacelles, which will plug this cylinder 32.

FIG. 2A schematically shows the operation of the conveyor 50 carrying the n-boats, at the junction between a horizontal tunnel 10, 20 and a vertical well 30, 40 for example the top left-hand corner of the installation of FIG. to facilitate the presentation 7 of the state of the art and its comparison with the invention, it will be assumed that the pulley 51-54 has a zero diameter; it is represented by the point T2. As indicated, the efficiency of the tunnel dryer 1 depends inter alia on the speed of circulation of the pods 55 in the tunnels and also of the interval separating two pods 55, it is necessary to bring the nacelles (or swing) as much as possible while avoiding the collision between two successive nacelles at a level of reference between the horizontal direction and the vertical direction as shown in Figure 2A. To simplify the presentation, references specific to FIG. 2A (or subsequently FIG. 2B) have been used; thus, the nacelle carries the reference N. The path of the conveyor chain 50 driving the nacelles N is represented by the path TO, Ti, T2, T3, T4 corresponding to the characteristic points of the path. By hypothesis, the horizontal path TO, Ti, T2 joins the vertical path T2, T3, T4 of the chain at the pulley T2 which is of zero radius in this example of principle. The nacelle N has a rectangular shape of vertices A, B, C, D; it is attached to the middle M of its upper side AB to the chain 50. The width of the nacelle N corresponds to the side AB and its height to the side BC. Half width is AM or MB. The diagram shows the three characteristic positions N1, N2, N3 of a n-boat respectively upstream of the angle gear, in the angle gear and downstream thereof. These three positions 25 are joined and highlight the problem of collision at the passage of the PC contact point. The first position N1 of the nacelle is that of the end of its horizontal path in the tunnel, when the nacelle begins to penetrate into the vertical well continuing to flow in the horizontal direction to its position N2. The position N1 of the nacelle is defined by the points Al, B1, Cl, Dl of the vertices. The second position shown N2 is that of the point of attachment (M2) arrived on the pulley T2. The position of the tops of the nacelle are references A2, B2, C2, D2. In the case of a pulley of non-zero radius, the pulley will be schematically tangential to the two segments T 1, T2 and T2, T3.

The positions N1 and N2 are joined so that the distance T1T2 is equal to the half-width of a nacelle. The third important position in this context is the N3 position of the nacelle lowered from its N2 position by a height of na-that. In this position N3, the vertices bear the references A3, B3, C3, D3. For two successive nacelles occupying the positions N1, N3 do not collide, it is necessary that if one of the nacelles occupies the position N1, the gondola which precedes occupies at least the position N3. If it occupies an intermediate position N2-3 between the positions N2 and N3, its vertex B3 will hinder the arrival of the vertex D 1 of the na-that N1 in the zone represented by the rectangle A2, B2, C2, D2 which corresponds to the change of direction. Conversely, if the nacelle were located lower than the N3 position, the interval between the fixing points of two successive nacelles would be increased unnecessarily. In summary, the minimum possible distance separating the attachment points M of two successive nacelles is the length of the chain between the points M1 and M3, that is to say the distance M1, T2, T3, M3. Since the segment (M1T1) is half the width AB of a nacelle and this distance is equal to the distance (T1T2), the minimum interval between two nacelles in the known installation is equal to the sum of the width of the nacelle and its height. This theoretical minimum distance does not take into account the radius of the pulley T2 and a precautionary interval that is reserved between two nacelles. The precise calculation of this distance will be made with the aid of the diagram of FIG. 5. FIG. 2B, positioned with respect to FIG. 2A, shows the path of the chain at an angle gear according to the invention. . The trajectory of the chain conveyor 50 is defined by the points T0, Ti, T5, T6 and the characteristic positions of nacelles N11, N3, N4 as well as an intermediate position N11-3 between the positions N1 1, N3. The vertices A, B, C, D of the nacelle are not all referenced in the different positions to avoid cluttering the drawing.

The path of the conveyor TO, Tl, T5, T6 according to the invention differs from the path TO, T1, T2, T3, T4 of the known installation according to FIG. 2A in that the path portion T1, T2, T3 is replaced by the diagonal Tl, T5 which reduces the minimum spacing between two successive nacelles to avoid their collision at the PC corner. The reference pulley T2, known, is replaced by a return pulley installed at the point Ti and is completed by a deflection pulley installed at point T5. The two pulleys are of zero diameter in this example also for simplicity bear each time the reference points Tl, T5. The two characteristic positions around the contact point PC, identical to that of FIG. 2A since the tunnel 10, 20 and the well 30, 40 are unchanged, make it possible to calculate the minimum chain length between two closest successive nacelles. The chain length between the attachment points M11 and M3 is equal to the sum of the diagonal T 1 T5 and the segment T 1 T 11. The intermediate position N11-3 is shown to show the displacement of the nacelle between the two typical positions N11 and N3. The position N4 shows the nacelle which precedes the nacelle at the position N3, at the minimum distance defined according to the invention. The comparison of FIGS. 2A, 2B linked by return lines shows that the spacing gain between the attachment points M of the two successive nacelles is equal to the difference between the sum of the length of the diagonal T1-T5 (which is the diagonal of a half-nacelle) and the sum of the width and the height of the nacelle this corresponds to the difference between, on the one hand, the sum of the height BC and 1/2 AB and, of on the other hand, the hypotenuse of this right triangle. For this tracing of the chain 50 of the conveyor, there can not be a collision since the point of contact PC is bypassed. Thus, in summary, the theoretical minimum distance between the attachment points of two successive nacelles is equal to the sum of the width of the half-nacelle and the length of the diagonal of a half-nacelle.

10 A simple numerical calculation (right triangle 2-3-4) shows that the reduction of the interval between successive nacelles can represent a gain of the order of 30 or even 40%, which is considerable. In practice, this distance also takes into account the diameter of the pulleys T1, T5 and the guard distance which it is desired to add as a precautionary measure. Figure 3 shows a tunnel dryer (s) 100 according to the invention in which the angle references 151-154 are made according to the principle shown in Figure 2B. This dryer 100 consists of two parallel tunnels, a lower tunnel 110 and an upper tunnel 120, or greens at both ends to open into connecting wells 130, 140. The circuit formed by the two tunnels 110, 120 and the two connection well 130, 140 is traversed by an endless conveyor 150 formed of two chains carrying pods or swing frames 155 in which the products to be dried are loaded. These nacelles 155 are laterally provided with rollers so as to roll in lateral rails inside the two tunnels whereas at the level of the wells in their downward or upward movement, the nacelles are suspended freely in the chain. These particular means are not represented. The tunnel dryer 100 is traversed countercurrently by a hot air vein (arrow G) supplied by a hot air generator 170 provided with heating and driving means such as fans, not detailed, leading to the lower tunnel 110 near its exit 111 to bypass the descent well 130 of the nacelles by a bypass 171 provided with a vacuum cleaner or fan 172 to open into the upper tunnel 120, still against the current of the nacelles 155. Near from the end through which the upper tunnel 120 opens into the upwell 140, the hot gases are sucked by the vacuum cleaner 173 which discharges the main part of the hot gases loaded with moisture into the chimney 174. A fraction of the gases The heat is taken near the exit of the tunnel 120 by the hot gas heating and circulation system 170 to be reinjected into the lower tunnel 110. Allocation, the entry and exit of the products 35 for the nacelles are at the loading / unloading station 160 integrated into the hoistway 140. The station comprises a passage 161 through which the nacelles 155 with a double opening 162, 163 on both sides, to access both sides of a

11 nacelle stopped in this opening for loading and unloading. These operations can be done simultaneously: the unloading through the opening 162 and the loading through the opening 163 with non-detailed means.

It is interesting to note that, moreover, this invention makes it possible to increase the free space between the upper and lower tunnels, thus offering the possibility, if necessary, of installing a loading station separate from the unloading (for example for special products or for high rates of handling).

The nacelles provide a certain seal at the loading / unloading station 160 vis-à-vis the depression created in the top of the well 140 by the vacuum cleaner 173. In the well 130, between the diverting pulley 151B and the pulley deflection 152B, there is an airlock 131 formed by a cylinder 132 constituting with the successive nacelles, a plug avoiding the passage of hot gases. As the distance W between the return pulleys 151B, 152B makes it possible to give the cylinder 132 a sufficient length, there will always be two homologous parts 155i of two successive nacelles 155 inside the cylinder 132 so as to form a stopper avoiding the passage of the hot gases forming the airlock 131 by cooperation with the bottom wall 155I full of each nacelle 155. The nacelles 155 are sufficiently close to each other so that the cylinder 132 can register in the height separating the above the lower tunnel 110 and the underside of the upper tunnel 120.

The four angle references 151-154 at the entrance and exit of the upper tunnel 120 and that of the lower tunnel 110 communicating with the two wells 130, 140, are produced according to the invention as shown schematically in FIG. 2B. The chain (or pair of chains) 150 passes over a return pulley 151A-154A and a deflection pulley 151B-154B so as to incline the path traveled by the chain 150 as has been described and shown with reference to FIG. 2B. The nacelles or swings 155 are at the minimum distance defined above thanks to the deflection pulleys 151B-154B provided at the level of each angle gear 151-154.

FIG. 3 also shows that it is in principle immaterial that the pods 155 move from the right to the left in the upper tunnel or from the left to the right (arrow F), the operation of the angle gears 151-154 according to the invention being necessary both for the

12 junction of the upper tunnel 120 with the descent shaft 130 with the upwell 140 and vice versa for the lower tunnel 110 with the upwell 140 and the descent well 130. In this installation, one of the pulleys of return is the driving part, for example, limb 154A. The tunnel dryer 100 shown in FIG. 3 comprises a lower tunnel 110 buried so that the loading / unloading station 160 of the products is situated at a height easily accessible to handling equipment. The upper tunnel 120 is carried by a non-detailed frame. The burial of the lower tunnel 110 is also of interest for thermal insulation problems since the lower tunnel is the hottest part of the installation. The invention relates not only to the design and construction of a tunnel dryer but also to the transformation of existing tunnel dryers. Thus, to transform the existing dryers, it is enough to renew the wells at the entrance and exit and change the chains to ensure the hooking of the swings to the new attachment points without intervention on horizontal traffic.

FIG. 4 shows another variation of kiln 200 of the invention that differs from the tunnel dryer of FIG. 3 in that it concerns the transformation of existing tunnel dryers and whose height difference H between the lower tunnel 210 and the upper tunnel 220 is not sufficient to allow the installation of the diverting pulleys and to respect the minimum distance W between the two deflection rollers 251B, 252B or 253B254B in the wells 230, 240, especially in the well. 230 to realize the airlock avoiding the short-circuit by the hot gases between the upper tunnel 220 and the lower tunnel 210. For this, the two ends 211, 212; 221, 222 of the lower tunnel 210 and the upper tunnel 220 are transformed to accommodate a deflection pulley 251B-254B by lowering or very locally raising the path of the chain 250 of the nacelles 255 just upstream (downstream) of the pulley 251A-254A. For this purpose, in the four angle references 251-254, the return pulley 251A-254A and the deflection pulley 251B-254B are combined with an auxiliary pulley 251C-254C which gives the path followed by the chain. 250 between the idler pulley and the diverting pulley, an

13 outward, that is, downward or upward along the corner of the dryer. Thus, the pairs of pulleys formed each time of a deflection pulley 251A-254A and a deflection pulley 251B-254B, are displaced out of the way that the chain 250 would follow if it passed over the pulleys. of return, usual so as to respect the minimum distance W. It is thus possible to form an airlock 231 between the two deflection pulleys 251B, 252B by a cylinder 232 of section corresponding to the horizontal section of the pods 255 so that the passage through the cylinder, the nacelles form a plug. In addition, as the nacelles are very close together thanks to the provisions of the invention, it suffices that the na-ones 255 have a solid bottom as already indicated, consisting of a solid sheet, to automatically form a plug in the cylinder 232. As in the previous installation, the hot gases flow in the direction of the arrow G. The hot gases are introduced near the exit in the lower tunnel 210 to get out and take a bypass 270 bypassing the airlock from outside to pass by a vacuum fan 272 and be reintroduced into the upper tunnel 220 still against the current (G) relative to the direction of circulation of the boats 255. At the other end of the upper tunnel 220, the hot gases are extracted by a vacuum cleaner 273 which discharges them into the chimney 274. As in the previous example, the loading / unloading station 260 situated in the well 240 comprises a passage 261 with two openings 262, 263 to allow simultaneous unloading / loading of a nacelle. The installation supplying the hot gases and driving them is not shown in this figure. It is simply noted that this installation introduces the humid gases at the entrance of the lower tunnel 210 and takes a fraction of the hot gases from the upper tunnel 220 near its outlet, the remainder being discharged through the chimney 274. The dryer described above requires for driving the chains with the nacelles, only one driving pulley, for example the pulley 254C. The other elements of the dryer are identical or similar to those already described and have the same references as the similar elements of Figure 3, whose references are increased by 100.

FIG. 5 shows another variant embodiment 300 of the invention which combines the two solutions given in FIGS. 3 and 4. In the upper part, the tunnel 320 and the wells are those of the embodiment of FIG. 3 and, in lower part, the lower tunnel 310 and the wells are those of the embodiment of Figure 4 or vice versa. This solution can be adapted for certain new or transformation installations, depending on the height H available between the lower tunnel 310 and the upper tunnel 320 and / or the depth of burial of the lower tunnel 310.

This installation 300 will not be described in detail. The different constituent elements bear the same references as in FIGS. 3 and 4 and which, as the case may be, have been increased by 200 for the references of the elements coming from the embodiment of FIG. 3 and 100 by those of the elements coming from the mode. In this design, it is interesting to observe that the total height of the dryer, in current section, is significantly reduced compared to FIG. 3.20 DIGITAL EXAMPLES

The invention will be explained hereinafter by the comparative calculation of the interval between two nacelles of a tunnel dryer, known, according to FIG. 1, of a first embodiment of a tunnel dryer according to FIG. invention shown in Figure 3 and a second embodiment of a tunnel dryer shown in Figure 4. These calculations are made at the junction of a horizontal tunnel and a vertical well and take into account real data, that is to say the size of the nacelles (also called swings), namely their height and width and the radius of the pulley and a guard distance which is usually applied in addition, as a precautionary measure. The calculation concerning the known dryer will be done using the diagram of FIG. 7, the calculation of the first embodiment of the invention will be done using the diagram of FIG. 6 and that of the second embodiment of FIG. the invention, using the diagram of FIG. 7. 1 °) Calculation of the minimum pitch of the nacelles on the existing installation (FIGS. 1, 6). The legend of the references of FIG. 6 is the following: H = Platform height La = Platform width Ra = Radius of the pulley C = La - Ra T = Diameter of the pulley Ha = H + 20 mm of guard Y = txII / 4

According to FIG. 6, the minimum pitch between nacelles is as follows: P = B + Y + C • Numerical example Dimensions of the platform: 30 Height = 1990 mm (H) Width = 860 mm (La) Diameter of the pulley = 647.22 mm (T) (10 teeth at 200 mm pitch)

Calculation of BB = Ha - Ra 35 Ha = H + 20mm = 1990 + 20 = 2010 Ra = 0/2 = 647.22 = 323.61 B = 1686.30 mm Calculation of YY Tx3,14 647.22mm x3.14 _508'06mm 4 4

Calculation of C C = La - Ra La = 860 mm Ra = 323.61 mm 5 C = 860 - 323.61 = 536.39 mm

Pas = B (1686.30) + Y (508.06) + C (536.39) P = 2730.75 mm = 273 cm

The attachment points of the nacelles must take into account the length of the links of the chain and as for reasons related to the structure of the chains, a nacelle can be attached to only one link out of two, the real pitch of the nacelles holding account of the pitch of the links of the chain which is equal to 200 mm or 400 mm for two successive links. The actual pitch between two nacelles will be equal to 7 x 400 = 280 mm. 15

2 °) Calculation of the minimum pitch of the nacelles according to the first embodiment (FIGS. 3 and 7) The references of FIG. 6 have the following meaning: H = platform height La = platform width Ra = radius of the pulley 0T1 = diameter pulley N ° 1 0T2 = Pulley diameter N ° 2 Ha = H + 20mm of guard 25 a = Angle given by the two nacelles in minimum position with the 20mm of guard f3 = Angle formed by the chain with respect to the vertical = 180 ° + a 0 = center pulley N ° 1 01 = Center pulley N ° 2

According to Figure 7, the minimum pitch of the nacelles is as follows: 30 Pitch = AB

Pas = AB BC + AC + Ha = H + 20mm 35 AB2 = AC2 + BC2 AB = VAC2 + BC2 16 20 • Calculation of the angle a BC Tangent of A = = a AC • Calculation of the center O of the pulley Ti relative to the attachment of the car A AE cosa = AE = cosa x A0 A0 = Ra AE = cosa x Ra A0 OE sina = OE = sina x A0 A0 = Ra OE = sina x Ra A0 • Calculation of the center 01 of the pulley T2 with respect to the attachment of the pod B 10 Computation of the angle 180 180 ° -a = f3 CBD = 90 ° = + S2 S2 = 90 ° - cosI1 = 2 2 BF = COSS2 × BO1 BO1 = Ra 01F 15 BF = cosIlxRa sinQ = BOl

01F = sin) xBO1 BO1 = Ra 01F = sine x Ra • Calculation of the horizontal distance of the centers of the two pulleys 01-O horizontal = The - BF + AE • Calculation of the vertical distance of the centers of the two pulleys 01-0 vertical = Ha - OE + 01-F • Numerical example 25 Dimensions of the platform Height = 1990 mm (H) Width = 860 mm (la) Diameter of the two pulleys Ti and T2 = 647,22 30 • Calculation of the minimum pitch with guard 20 mm Pas = AB BF BOl 15 BC = La = 860 mm AC = 2010 mm AB = / 20102 +8602 = V4779700 AB = 2186.25 mm Calculation of the angle at BC The 860 Tangent of A = __ = 0.428 = 23 ° 18 AC Ha 2010 • Calculation of the center O of Ti at the attachment A of the upper nacelle AE cosa = A0 AO = Ra = 323.61 a = 23 ° 18 cos23 ° 18 = 0.920 AE = cosa x Ra = 0.920 x 323, 61 = 297.72 mm 298 mm OE sina = A0 AO = Ra = 323.61 a = 23 ° 18 sin23 ° 18 = 0.394 OE = sina x Ra = 0.394 x 323.61 = 127.60 z-127.5mm Calculation of the center 01 of T2 at the attachment B of the lower nacelle Calculation of the angle S2 f3 = 180 ° - a = 180 ° -23 ° 1 8 = 156 ° 82

CBD = ù + S2 = 90 ° = 90 ° - 156 ° 82 S2 = 11 ° 59 2 2 BF 20 cosI1 = BO1 = Ra = 323.61 S2 = 11 ° 59 B01 cos 11 ° 59 = 0.980 BF = cosL x Ra = 0,980 x 323.61 BF = 317 mm 01F sinQ = BO1 BO1 = Ra = 323.61 S2 = 11 ° 59 sinl 1 ° 59 = 0.201 25 01F = sinQ x B01 = 0.201 x 323.61 = 65 mm • Calculation of the horizontal distance between the centers of the two pulleys 01-O horizontal = La - BF + AE

The = 860mm BF = 317mm AE = 298mm 30 01-0 horizontal = 860 - 317 + 298 = 841 mm 1015

• Calculation of the vertical distance of the centers of the two pulleys 01-0 vertical = Ha - OE + 0 Ha = 2010 OE = 127.5 mm 01-F = 65 mm 01-0 vertical = 2010 - 127.5 + 65 = 1947 , 5 mm

Calculation of the actual pitch of the nacelles according to the pitch of the chain links Chain pitch = 200 mm Min. Pitch or AB = 2186.25 mm

The actual pitch of the nacelles will be optimized by a multiple of a single step of the chain. Not real = 2200 mm 3 °) Calculation of the minimum pitch of the nacelles of the dryer according to FIGS. 4 and 8 Before calculating the minimum distance between two nacelles, the pulley will be examined for the calculation of the pitch diameter of the pulley in the case of a chain of 20 mm links and a 16-tooth pulley. Chain pitch 200 mm Number of teeth 16 teeth 25 Angle a of each tooth 360 ° u = = 22 ° 50 16 • Calculation of A0 (radius of the pulley). a AB sin ù ù 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 11 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 , 82 x 2 = 1025.64 • Calculation of the minimum pitch of the nacelles and the positioning of the three pulleys (figure 8) H = Platform height 20 La = Platform width

RaT1 = Pulley radius 1

RaT2 = Pulley radius 2

RaT3 = Sheave radius 3 0T 1 = Sheave diameter Ti 0T2 = Sheave diameter T2 Ha = H + 20 mm guard a = Angle given by both nacelles in minimum position with 20 mm guard f3 = Angle formed by the chain relative to vertical = 180 ° -a S2 = Angle resulting from the bisector of 13 CBD = 90 = + S2 2 52 = 90 ° - [3/2 O = Center pulley N ° 1 Pitch = AB 01 = Center pulley N ° 2 BC = The

02 = Center pulley N ° 3 AC = Ha = H + 20 mm

0T3 = T3 pulley diameter AB2 = BC2 + AC2 AB = jAC2 + BC2 Calculation of the tangent angle of A = BC AC 30 • Calculation of the center O of the pulley Ti with respect to the attachment of the upper basket A AE 25 cosa = AE = COSa x A0 A0 = RaT1 AO AE = cosa x RaTl OE sina = OE = sina x A0 A0 = RaTl AO OE = sina x RaTl • Calculation of the center 01 of the pulley T2 with respect to the attachment of the lower platform B Calculation of the angle S2 21 180 ° -a = (3 CBD = 90 ° = - + S2 e = 90 ° - (3/2 BF cose = BOl BF = cose x BO 1 BO 1 = RaT 2 BF = cosco x RaT2 01F sine = BOl 01F = sine x B01 BO 1 = RaT2 01 F = SINe x RaT2 • Calculation of the horizontal distance of the centers of the two pulleys 01-0 horizontal = La - BF + AE • Calculation of the vertical distance of centers of the two pulleys 01-0 vertical = Ha - OE + 01-F • Calculation of the distance from the center O (pulley Ti) to the center 02 (pulley T3) K = variable side never less than the width The + 640 mm from the nacelle • Calculation of distance from center O (Ti pulley) to center 02 (in ulie T3) J = 0-01 vertical - (RaT2 + raT3) • Numerical example 20 Dimensions of the platform: Height = 1990 mm (H) Width = 860 mm (The) Diameter of the pulleys = 0T1 = 1025.64 mm = 0T2 = 647.22 mm 25 = 0T3 = 1025.64 mm Distance K (0-02 horizontal) The + 640 mm = 860 + 640 = 1500 mm • Calculation of the minimum pitch with guard of 20 mm Pas = AB 30 BC = La = 860 mm AC = Ha = H + 20mm = 1990 +20 AC = 2010 mm AB = V20102 + 8602 = V4779700 AB = 2186.25 mm • Calculation of the angle at BC The 860 Tangent of A = _ù_ = 0.428 AC Ha 2010 Tangent of A = 0.428 = 23 ° 18 • Calculation of the center O of Ti at the attachment A of the upper nacelle AE cosa = A0 A0 = RaT1 = 512.82 mm a = 23 ° 18 cos 23 ° 18 = 0.920 AE = cosa x RaTl = 0.920 x 512.82 = 471.79 mm 10 AE = 472 mm OE sina = A0 OE = sina x RaTl = 0.394 x 512.82 = 202.05 mm z-202 mm • Calculation of center 01 of T2 to the attachment B of the lower nacelle 15 Calculation of the angle e f3 = 180 ° - a = 180 ° -23 ° 18 = 156 ° 82 CBD = ù + S2 = 90 ° e = 90 ° - 156 ° 82 = 11 ° 59 2 2 cos e = B01 = RaT2 = 323.61 11 ° 59 cos 11 ° 59 = 0.980 BF B01 BF = cose x RaT2 = 0.980 x 323.61 20 BF = 317 mm 01F sine = BOl 01F = sine x B01 = 0.201 x 323, 61 = 65.04 mm 65mm • Calculation of the horizontal distance between the centers of the two pulleys 25 01-0 horizontal = La - BF + AE

The = 860 mm BF = 317 mm AE = 472 mm

01-O horizontal = 860 - 317 + 472 = 1015 mm

30 • Calculation of the vertical distance of the centers of the two pulleys BO1 = RaT2 = 323.61 e = 11 ° 59 sinl 1 ° 59 = 0.201 01-0 vertical = Ha - OE + 01-F Ha = 2010 MM OE = 202 mm 01-F = 65 mm 01-0 vertical = 2010 - 202 + 65 = 1873 mm • Calculation of the distance from the center O (pulley Ti) to the center 02 (pulley T3) (0-02 horizon-tale) K = The + 640 never lower K = 1500 mm • Calculation of center distance O (pulley Ti) at center 02 (pulley T3) (0-02 vertical) J = 0-01 vertical - (RaT2 + raT3) RaT2 = 323.61 mm RaT3 = 512.82 mm 0-Olvertical = 1873 mm J = 1873 - (323.61 + 512.82) = 1036.57 z-1037 mm • Calculation of the real pitch of the nacelles Identical to the version N ° 2 Pas real = 11 x 200 = 2200 mm20 NOMENCLATURE 1 10 11 20 21 22 30, 40 l0 31 32 32

50 51-54 15 55 55S 55I 56

20 60 61 62 63

25 70 71 72 73 74 30 Tunnel dryer Tunnel tunnel End tunnel Tunnel tunnel Tunnel outlet Tunnel well Cylinder

Chain Deflection pulleys Nacelle Upper wall Lower wall Hanging point of the nacelle

Loading / unloading station Cylinder Unloading opening Loading opening

Equipment generating hot air Deflection Fan Aspirator Chimney. . . F Travel direction of nacelles G Direction of circulation of hot gases N N1-N4 platform Parts of the nacelle 35 A-D Platform tops

100 Tunnel dryer 110 Lower tunnel 111 Tunnel end 120 Upper tunnel 121 Tunnel entrance 122 Tunnel exit 130.1 40 Well 131 Airlock 132 Cylinder

150 Chain 151-154 Deflection pulleys 155 155S aerial 155I top wall Bottom wall 156 Platform nock 160 Loading / unloading station 161 Passage 162 Unloading opening 163 Unloading opening 170 Hot air generator 171 Bypass 172 Fan 173 Vacuum cleaner 174 Chimney. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 Tunnel dryer 210 Lower tunnel 211 Tunnel end 220 Upper tunnel 221 Tunnel entrance 222 Tunnel outlet 230, 240 Well 231 Lock 232 Cylinder

250 Chain 251-254 Deflection pulleys 26 255 Nacelle 255S Nacelle upper 255I Nacelle base 256 Nacelle attachment point 260 261 262 263 10 270 271 272 273 15 274 Loading / unloading station Cylinder Unloading opening Unloading opening

Hot air generator Bypass Ventilator Vacuum Cleaner Chimney ......................................... ................................. ................. .................... 300 310 311 20 320 321 322 330, 340 331 25 332

350 351-354 355 30 355S 355I 356 Tunnel dryer Tunnel tunnel End tunnel Tunnel tunnel Tunnel outlet Tunnel well Cylinder

Chain Deflection pulleys Nacelle Upper nacelle Lower nacelle Platform attachment point 360 35 361 262 363 Loading / unloading station Cylinder Unloading opening Unloading opening 370 Hot air generator 371 Bypass 372 Fan 373 Vacuum cleaner 374 Chimney

Claims (1)

CLAIMS 1 °) Tunnel dryer for building products such as bricks or tiles comprising a lower tunnel (110) and an upper tunnel (120), connected at each end by a well (130, 140), forming a circulation path constituted by the succession of the lower tunnel, a well, the upper tunnel and a well, this loop path being traversed by a chain conveyor (150) to which are suspended pods (155) receiving products to dry, - the chain (150) passing from a horizontal path to a vertical path (or vice versa) at the junction (151) of a tunnel (110, 120) or a well (130, 140) by a angle gear (151-154), the nacelles (155) being separated from the minimum gap necessary to avoid the collision of two successive nacelles at the junction (151-154) of the horizontal path and the vertical path (or conversely ), the chain (150) passing over a pulley (151A-154A) at each junction, the pods (155, N) generally have a rectangular cross-section with a point of attachment (M) to the chain (150) in the middle of their width, characterized in that at each cross-section (151-154) of the path rectangular, at the well (130, 140), the return pulley (151A-154A) at the end of the horizontal path is completed by a deflection pulley (151B-154B) installed in the well (130, 140) of in that the chain (150) passing around the deflection pulley and the deflection pulley follows an inclined path (T 1 T5) substantially corresponding to the hypotenuse (Mi 1 D 1 1) of the right triangle (Al 1M 11 D 11) taken from the rectangle (ABCD) formed by the nacelle whose vertical side (Al 1 D11) is equal to the height of the na-that (N11, 155) and the horizontal side (Al 1M 11) is equal to the half width (AM, 1/2 AB) of the nacelle (N11, 155) to its suspension point (M) at the chain (150). 2) tunnel dryer according to claim 1, characterized in that the return pulley (251A-254A) and the deflection pulley (251B-254B) are supplemented by an auxiliary pulley (251C-254C), creating a deflection towards the outside of the travel path of the chain (250) which would pass only on the return pulleys, to sufficiently distance the deflection pulleys (251B-254B) from the well (230), to create an airlock (261) closed 29 by one or two successive nacelles (255) and blocking the passage of hot gases from the upper tunnel (220) to the lower tunnel (210). 3) tunnel dryer according to claims 1 and 2, characterized in that it comprises, for one of the tunnels (310, 320), at the junction the wells (330, 340), a pulley and a deflection pulley and, for the other tunnel (310), at each end, a return pulley combined with a deflection pulley and supplemented by an auxiliary pulley creating the outward deflection of the chain circulation path (350). ). 4) Tunnel dryer according to claim 1, characterized in that the nacelle (155, 255) comprises a single solid partition (155I, 255I) or (155e, 255e) to close an airlock (131, 231) of the connecting well. the lower tunnel (110) to the upper tunnel (120) in the direction of movement of the nacelles (155) .20