WO2009021472A2

WO2009021472A2 - Method of saw timber drying and device for its using

Info

Publication number: WO2009021472A2
Application number: PCT/CZ2008/000088
Authority: WO
Inventors: Radovan Vojtasík
Original assignee: Vojtasik Radovan
Priority date: 2007-08-13
Filing date: 2008-07-24
Publication date: 2009-02-19
Also published as: WO2009021472A3; CZ303305B6; WO2009021472A9; EP2195594A2; WO2009021472A4; EP2195594B1; CZ2007539A3

Abstract

Pilling strips (2) are double-sided applied on saw timber (1) and then, during drying, is induced pressure power by forcing mechanical means to saw timber (1) from opposite sides, but on other sides of saw timber (1) than pilling strips (2) are. Preferably such counteracted to whole saw timber (1) layers in chocks, which layers are arranged as areal planar formation, pressure power is at least in intensity sufficing to force saw timber (1) to each other and keeping them without gaps. Device for using this method contains piling strips (2) provided with a pair of arresting stops (4,5). At least one of them is movable, provided with force element (6). Preferably, piling strips (2) are firmly attached with a gap between them in which is situated force element (6), preferably spring. Movable arresting stop (5) is preferably provided with setting element (8). Unit is provided at least with pressing element (11) for pressing perpendicularly towards arresting stops (4,5) movement.

Description

Method of saw timber drying and device for its using

Technical field

The invention relates to the field of woodworking industry. A new method of drying of lump wood is resolved generally while the invention is suitable especially for drying of saw timber. Then there is also resolved the device for drying of saw timber providing to use the new method.

Background Art

The problems of wood drying are connected to saw timber first of all. As saw timber is meant the wood after cutting to pieces, which is in a form of so called trimmed saw timber or non-trimmed saw timber after primary treatment by the way of cutting to pieces or which is in a form of lamellas, balks, veneer and the like.

The existing methods of saw timber drying deal particularly with temperature, moisture and provision of flow of medium serving for a discharge of moisture during drying. Saw timber drying is commenced by cutting the original material to pieces in fact when it is under progress in common surrounding under natural conditions. The industrial methods of drying are implemented by the way of drying in chambers or in other determined rooms. The saw timber is dried in a form of individual pieces or in most cases in a form of so called chocks which are the systems where the saw timber is laid loose in layers one above another and individual layers are interlaid by so called piling strips. Each layer of saw timber creates an areal flat formation and there are gaps created among them by the means of so called piling strips which gaps serve for circulation of medium which draws discharged moisture off. The bodies of simple form, for example lathes, balks, boards and similar simple items which allow creation of gaps among individual layers of the saw timber are used as piling strips. Sometimes there is a weight put additionally on the chock of saw timber in order to increase an effect of weight influence and thereby to limit undesirable warping of the saw timber during drying. The processes of drying are constantly forwarded and improved. The drying processes are known from number of documents. The methods of drying as well as methods serving for forwarding and improvement of drying are focused on physically-chemical influence on the saw timber. This is first of all a choice of suitable surrounding for drying, a temperature, moisture, influence of microwaves, for example according to WO 82/01766, conservation of dissimilar percent of humidity of drying surrounding when compared with the moisture of saw timber as for example according to WO 82/01411 and the like. These existing methods reach their effect in fact only by the way of creation of fit surrounding for dried saw timber and devices for implementation of these methods are represented by chambers equipped with means leading to creation of desirable surrounding.

The disadvantage of existing methods of saw timber drying and of devices for implementing these methods is the fact that they do not solve the problem of undesirable breaks in fibres and of warping of form of the saw timber during drying fully and sufficiently from the point of view of economy. The problem arises in such a way that the dimensions of saw timber are lessened by drying which results in a creation of breaks in the wood and in creation of cracks and gaps among individual pieces of the saw timber in the layers of chock. That is to say the decreasing of the dimensions induces tension and movement of material while cracks and gaps arising concurrently among individual pieces of material facilitate warping and breaking and they even help to the fixation of arisen breaks and deformations. Because the saw timber is laid loose in chocks, the piling strips among the layers of saw timber cannot prevent undesirable mentioned effects of drying.

The method of saw timber drying with the exploitation of creation of certain pressure in a drying room is described in application WO 1999/023429 (PCT/FR 1998/002318). The method consists in pressurising a sealed chamber to the pressure determined in advance by the way of injecting or by the way of generating saturated vapour and in maintaining such pressure for a predetermined time interval at concurrent conservation of forced circulation of air and saturated vapour in the chamber. Then heating the wood core by emitting of microwaves and drawing off the liquid exudates coming down from the wood to the chamber base where they are collected is implemented. The device according to WO 1999/023429 contains a chamber interconnected with waveguide by the means of windows and equipped with elements serving for creation and preservation of the stated physically-chemical processes in the cavity of chamber. There is a saw timber found in the chamber which saw timber is piled on chocks during drying. The chocks are created on the truck which allows the transport from and to the chamber. There is no operation by any mechanical means made on the chocks themselves or on the layers of the saw timber in the chocks during the process of drying. According to this patent the influence of pressure created by overall increase of pressure in the chamber cavity for a certain period of time has positive effects on the drying process. The document mentions the fact that the pressure increase reaches the limitation of the breaks in wood fibres and reduces the rate of undesirable material deformations.

It is true that the increase of atmospheric pressure in the room of drying partially limits the breaks of fibres of wood material however in fact the spatial dry shrinkage of material and its consequences are not limited. That is why the consequences of dry shrinkage of material which is accompanied by reduction of volume of dried saw timber are not eliminated either at this way of drying and at utilization of stated device. There are gaps created among individual pieces of material, pieces laid in the layer side by side, during drying in the same way as at the other existing methods of drying and at existing devices as a consequence of dry shrinkage, and this spatial clearance allows breaking, warping and undesirable crimping of the saw timber.

Disclosure of Invention

The invention removes all the above stated disadvantages to a considerable extent. The method of saw timber drying use the dried pieces of saw timber which are also fixed against warping by the way of loading. Drying is implemented by placing of piling strips to two opposite sides of the dried pieces of saw timber when at the same time, with the view to the volume of these piling strips, there is a free space created by placing of these piling strips to and along the surfaces of saw timber where these piling strips are found. Then the moisture is drawn off through it during drying which moisture is discharged from the saw timber while besides the influence of weight caused by gravitation and by mass of saw timber and of piling strips there is at least a temporary pressure power induced on the dried saw timber during drying. The disclosure of invention consists in a fact that the pressure power is not of a character of mere increase of atmospheric pressure in the surrounding of drying kiln as it is at existing methods but that pressure power is induced by mechanical means, by their forcing down to the dried pieces of saw timber, namely in opposite directions which is realized on other two opposite sides when compared with position of piling strips. This accomplishes a compressing of saw timber or tapping individual pieces of saw timber down one to another as the case may be which prevents the creation of gaps between adjacent pieces of saw timber and it also prevents a creation of breaks at reduction of the volume of the wood by dry shrinkage, and as a consequence of the above stated it also prevents undesirable crimping and warping of saw timber. The additional influence of pressure power by the increase of atmospheric pressure or influence of microwaves or a combination with other modern methods of drying are not excluded by this anyway.

The dried saw timber is preferably first piled in at least one layer creating an areal plane formation and afterwards there are piling strips placed to the areal surfaces of this layer with forming free spaces created along those plane surfaces by the means of mentioned piling strips. During the drying there is a pressure power induced by the means of mechanical means which pressure power affects the lateral sides of the layer or layers of saw timber while the pressure power is induced as a pressure to the lateral sides of the layer of the saw timber in the opposite direction and in the direction of the course of planar surfaces of the layer at the same time. This is implemented continuously or interruptedly for a certain period of time while the pressure power is induced in the intensity sufficing at least to forcing the pieces of saw timber down to each other and keeping their position side by side even after reduction caused by dry shrinkage without creation of gaps between the pieces of saw timber lying side by side.

It is even more advantageous, especially for industrial drying of common saw timber, when the dried saw timber is piled on chocks which means in the layers creating areal planar formations situated in parallel levels one above another whereupon the pressure power induced by mechanical means in the opposite directions operates not only to the lateral surfaces of these layers but besides this also to the planar surfaces of the layers perpendicularly to the pressure power working in the direction of course of planar surfaces of the layers during the course of drying.

Imitated induction of pressure power on the saw timber at saw timber drying according to the invention need not be limited to the process of basic drying only. It is advantageous if the chocks or saw timber layers arranged to the utilization of the method according to the invention are brought under at least one of the consequent operations of saw timber treatment at which the saw timber is treated by chemical or biochemical processes. Preservation, saturation, penetration, staining and the like may occur as chemical or biochemical processes. It results in the fact that the saw timber is fixed during this process as well and so the creation of breaks or warping is limited. Then it also results in a considerable saving of necessary handling and this at the same time brings a time saving, power saving as well as financial savings. The device for saw timber drying, in the way understood according to the invention, contains at least two piling strips for application to the surface of dried saw timber where these piling strips are made as oblong bodies with thrust faces for propping of saw timber and they are situated on the body of the piling strip on the opposite side. The disclosure of the new solution is that at least one of these piling strips is equipped with a pair of arresting stops which are situated in the area of its opposite ends and at least one of those arresting stops is movable. The movable arresting stop is fixed towards the piling strip in a sliding way and it is equipped by at least one force element which is chosen in such kind and such position which allows its forcing down in the direction to the other one of this pair of arresting stops.

All the included arresting stops have advantageously at least one level pressure face created on them in order to induce a pressure power on the laid saw timber. This pressure area causes a better distribution of induced power and it prevents the wood material damage. It protrudes on the outside periphery of the piling strip on the side where there is a thrust face for saw timber created. At least two arresting stops of one piling strip are situated on the same side of piling strip which is at the same thrust face, and their pressure areas are situated against each other. The piling strip having more than two arresting stops has either all of them only at one thrust face or it has at least two ones at one thrust face and at least two ones at the opposite thrust face with an advantage. In practice the more simple solution with all arresting stops at one thrust face will be probably more preferably and more often used. At least two piling strips are preferably joined to each other firmly and immovably in a mutual parallel position and with a gap between them where this joint is realized by the means of fixed immovable joints while at least one pair of adjacent piling strips has common arresting stops. The force element or at least its part is situated in a gap between those piling strips joined to each other preferably. The force element is preferably created by at least one spring stretched in the gap between adjacent piling strips joined to each other which spring is fixed to the movable arresting stop by at least one its end. The fixed unit the internal space of which in the shape of gap between the piling strips may be utilized for a placement of a force element is acquired by the connection of the piling strips to each other as stated in the previous paragraph. The spring may be located there safely with no risk of warping or undesirable release and it provides with the advantages of spontaneously functioning system without a necessity of delivery of force from the outside. It may be stretched between the arresting stops through all the length of the gap between the arresting stops or it may be attached only in a part of a gap. Eventually two or more springs side by side or one behind another may be used according to the dimensions of the dried saw timber.

Articulated joint, movable, preferably pivoted arm and/or piston may be used as a force element in an alternative way or in addition which parts are placed in the device and they are fixed in such a way for their movable part to be attached to the movable arresting stop.

The movable arresting stop is preferably provided with at least one setting element serving for preservation of its position in stretched conditions. The screw, pin or any other common setting element may be used as a setting element which will allows a temporary fixation of the position of the movable arresting stop in stretched conditions in such a way for the piling strip to be able to be put on the saw timber or for the saw timber to be piled on the piling strip according to the invention. Then the saw timber is drawn together by the move of movable arresting stop in the direction to the opposite arresting stop by a simple release of setting element.

Between the opposite ends of the piling strip there are at least two movable arresting stops created preferably at one thrust face. Each movable arresting stop is attached to the force element. The solution with two arresting stops when both of them may be movable is advantageous especially at larger dimensions. The number of arresting stops higher than two may be advantageous for large dimensions, for example there may be an immovable arresting stop found between movable arresting stops and the like. This version of solution is suitable especially at larger dimensions, when the piling strips are longer then usually.

The piling strips may be preferably created as rods of tetragonal cross- section which rods are provided with arresting stops in the form of bodies which are also of the shape of rod and which have also tetragonal cross-section. This version is especially advantageous for its practicality and simplicity of workmanship however it does not limit a possibility to execute other shapes according to the intention and possibilities of manufacturer anyhow.

The advantages of the device according to the invention appear most efficiently at saw timber drying in bulk when the new drying device is used for saw timber in chocks. The device in such case is implemented as a modular set containing a set of piling strips in the chocks of saw timber where the piling strips are located in a parallel way to each other on the layer of saw timber with at least two layers of saw timber which are interlaid by piling strips and which are situated one above another. Individual pieces of saw timber of each layer are laid loose in these chocks side by side in a plane and they create areal planar formation between the arresting stops of the piling strips while the piling strips are laid on both planar surfaces of each layer of the saw timber. So the areal planar formation which is created by each saw timber layer in the device is propped there on the thrust faces of piling strips from above and underneath. The pressure areas of appropriate arresting stops are propped on lateral sides of the planar formation which is created by each saw timber layer.

All piling strips are also preferably interconnected each other firmly and immovably on one layer of the saw timber in the chock. This creates a set similar to grid which allows ventilation and discharge of moisture at saw timber drying with a possibility to take an advantage of induction of pulse, continuous or interrupted pressure on the saw timber by the way of mechanical means. The strength of the system and a possibility of simplification of handling, as for example relocation of all the grid at once from the exsiccated layer to the layer of saw timber which is in the stage of preparation for drying, is an advantage of the connection of the type of grid.

Attachment of the piling strips, the ones which do not create a fixed block with an attachment by welded bar or another practical block, is preferably executed as a unit which may be disassembled by the means of connecting elements of the demountable unit as for example bolts with nuts, clips, clamps and the like.

The chocks with saw timber are preferably provided with at least another pressure element located on the surface of the body which is created by the chock as a modular unit, namely in functional position to induce a pressure on the chock perpendicularly towards the direction of movement of arresting stops. This may be implemented easily, for example by the means of weights or pistons and rods and so on. Eventually the chock may be also provided with other additional piling strips which are of the same structure with the arresting stops as the piling strips incorporated in the chock, they are also situated parallelly against each other however along the lateral sides of the layers of saw timber, perpendicularly to the piling strips lying on planar surfaces of these layers. These additional piling strips are then provided with arresting stops and with force elements but the pressure areas of arresting stops of these additional piling strips are propped on the upper and lower wall of the chock. The saw timber drying device according to the invention can have a preferable variant at which the piling strips, movable arresting stop and force element are found within the frame construction. The immovable arresting stop may be created within the space of frame construction in such a case or it may be replaced by the wall of the frame construction. The force element or force elements as the case may be can be attached to the frame construction. Also box is understood to be a frame construction here. The invention is useable for saw timber drying, namely both of individual pieces and also of the saw timber in layers or in chocks. It is suitable for drying of various kinds of saw timber as for example veneer, lamellas, saw timber with bark and/or bast, as for example saw timber from frame-saw as well as saw timber free of bark as for example floorboards, boards, lathes, balks and others. It is suitable for drying in natural way in a common surrounding of terrain or of halls and also for methods of drying with utilization of drying halls, chambers or tunnels with the use of artificially crated conditions for drying as for example influence of heat, air circulation, decrease or increase of pressure, influence of microwaves, UV radiation and the like. Its main advantage is represented by the compensation of dry shrinkage which prevents creation of undesirable breaks in the wood and undesirable warping of the saw timber very efficiently. The advantage of the new technical solution according to the invention is represented also by its undemanding character for energy and independence on drying device with a possibility to combine a new method and the device with another drying device and methods additionally within a common process and in one period of time. Another advantage is represented by the possibility of its utilization in the field or in free environment, the possibility of the proposed device to be disassembled, its storability as well as a possibility of transport to any place as well as undemanding character for space.

Brief Description of Drawings

The invention is illustrated using drawings, where shows Fig. 1 view of the example device according to the invention with one dried layer of saw timber from the top, Fig. 2 view of the same from the front, meaning upon previous picture, Fig.

3 view of the same from the right side, meaning upon previous two pictures, Fig. 4 view of the device according to the invention with one dried piece of saw timber from the top, Fig. 5 view of the same from the front, meaning upon previous picture, Fig. 6 view of the same from the right side, meaning upon previous two pictures, Fig. 7 view of the device according to the invention with a chock of saw timber from the top, Fig. 8 view of the same from the front, meaning upon previous picture, Fig. 9 view of the same from the right side, meaning upon previous two pictures, Fig. 10 variant of the device with articulated joint, view from the front, Fig. 11 variant of the device with pivoted arms, view from the front, Fig. 12 variant of the device with combination of piston with frame construction, view from the front.

Disclosure of Invention Example 1

An example of embodiment of the invention is the method for saw timber drying and the device for using of this method according to Figures 1 to 3. The drying set which includes also dried saw timber 1 for clearness is demonstrated. The set is created in a modular way out of the pairs of piling strips 2 which are distributed parallelly partly on the bottom, under the dried saw timber ± and partly on the dried saw timber ±. There is a section comprising such a pair of connected piling strips 2 chosen for an illustration in the pictures, such sections are then repeated in all the length of the saw timber i in the same arrangement side by side. The chosen section contains two pairs of piling strips 2 above each other. Both these pairs of piling strips 2 are constructed in the same way. First of them is the upper pair of piling strips 2 lying on the saw timber ± on the top and the other one is found under this first one. The piling strips 2 themselves are of the shape and of dimensions which are known in the branch, suitable for adding to the surface of dried saw timber Λ. They are created as oblong bodies made of steel with flat thrust faces 3 for propping of the dried saw timber ± which thrust faces 3 are located on the body of the piling strip 2 from the opposite sides. The ends of piling strips 2 are welded on the fixed plates which create fixed joints among them this way and it allows the piling strips 2 to be fixed side by side in each pair firmly, in an undetachable way. One of these plates, in Fig. 1 and Fig. 2 on the right, is at once the fixed immovable arresting stop 4 for the laid saw timber 1- There is the movable arresting stop 5 found in the area of opposite ends of each pair of interconnected piling strips 2 which arresting stop is movable towards the pair of connected piling strips 2. The difference in the position of movable arresting stop 5 of the upper pair of piling strips 2 is well apparent in the pictures Fig. 1 and 2 at the stretched position of the device when compared with the position of the movable arresting stop 5 of the bottom pair of the piling strips 2 where there is a saw timber 1 included. The movable arresting stop 5 is provided with the force element 6 for its forcing down in the direction to the other one of this pair of arresting stops 4J5 which is to the immovable arresting stop 4.

Both arresting stops 4,5 have a lever pressure face 7 created on them for evocation a pressure power to the laid saw timber 1. Pressure face 7 protrudes on the outside periphery of the piling strip 2 on its side where there is thrust face 3 found. Both two arresting stops 4J5 are located on the same side of the piling strip 2, at the same thrust face 3^ and pressure faces 7 of these arresting stops 4J> are located against each other. Each of the demonstrated pair of the piling strips in the pictures Fig. 1 to

Fig. 3 is an independent detachable body. It is possible and also practical due to this fact that each pair of firmly connected piling strips 2 disposes of created common arresting stops 4,5 and in the gap which means in the space between the piling strips 2 there is a force element 6 found. In this exemplary embodiment of the invention, the force element 6 is in the preferably form of a spring. This is stretched between the arresting stops 4,5, where it is fixed to the movable arresting stop 5 by one end and to the immovable arresting stop 4 by the other end. The movable arresting stop 5 is provided with the bolt with nut in the position of setting element 8 for keeping its position in stretched conditions, which allows an easy storage of damp saw timber 1

The piling strips 2 are created in a simple practical shape as rods of the tetragonal cross-section and they are provided with arresting stops 4J5 in the form of plates which are also of the shape of a rod and of tetragonal cross-section.

The bodies of the pairs of the connected piling strips 2 are laid for drying on the saw timber 1 side by side, crosswise towards the saw timber 1 In the pictures Fig. 1 and Fig. 2 there are other screws apparent which screws are found at the fixed joints of the piling strips 2. They create fixation mandrels 9 which allow a fixation of piling strips 2 found one above another in combination with openings IQ in fixed joints of the piling strips 2. All the set is modularly built up in such a way that the pairs of piling strips 2 with arresting stops 4J5 in stretched conditions are placed side by side on the bottom. Then there is a layer of saw timber 1 laid down on the piling strips 2 crosswise towards them. The saw timber 1 has to be piled side by side. When the entire layer is laid down, another layer of pairs of piling strips 2 is laid down on the top of the saw timber 1. These pairs of piling strips 2 are connected to the pairs of piling strips 2 beneath. Then there are setting elements 8 released which release disengages force elements 6 in the shape of spring which will cause that the movable arresting stops 5 will be forced down on the layer of saw timber 1 and they start to induce a pressure power towards immovable arresting stops 4. This will put the device into operative conditions and it allows using of the new method of drying of saw timber JL

At this new method of drying of saw timber 1 there is at least a temporary influence on the dried saw timber 1 implemented by the means of pressure power induced by mechanical means, by their forcing to the dried pieces of the saw timber 1, namely in the opposite direction to the two opposite sides of the saw timber 1 when compared with the position of the piling strips 2 besides the fact that the dried pieces of saw timber 1 are fixed against warping by the way of loading by the means of adding the piling strips 2 to the two opposite sides of dried pieces of saw timber JL At such exemplary embodiment, the pressure power is induced by the force element 6 in the form of spring, which causes that the movable arresting stop 5 forces to a layer of the saw timber 1 down in the direction to the immovable arresting stop 4, whereby the layer of saw timber 1 is pushed down and individual pieces of saw timber I are pressed to each other. At this procedure the application of the pairs of piling strips 2 causes a creation of free space along those surfaces of the saw timber 1 where there are piling strips 2 found through which free space there is a moisture discharged from the saw timber 1 drawn off 1 during drying. The method of drying of saw timber 1 according to the pictures Fig. 1 to Fig. 3 thus represents the technical solution at which the saw timber i is first piled at least in one layer creating an areal planar formation when being laid to be dried. The piling strips 2 are then added to planar surfaces of this layer which piling strips 2 create free space around these planar surfaces. Under such conditions there is a drying implemented while during the drying a pressure force induced by mechanical means is induced on the lateral surfaces of this layer in opposite direction and at the same time in the direction of the course of planar surface areas of the layer. Such influence may be under progress continuously or interruptedly, for example in a way of pulses, for a certain period of time. The pressure power at it is induced in the intensity which is at least sufficient to force the adjacent pieces of saw timber 1 down to each other and to keep them side by side as close as possible even after reduction of volume caused by the dry shrinkage of the wood substance without creation of gaps if possible. The piling strips 2 are disassembled into individual pairs after exsiccation and they are put at suitable place or they are directly relocated on the new damp saw timber ± for other utilization while dried saw timber 1 is passed on other treatment or sale. It is purposeful to leave the piling strips 2 on the saw timber 1 as long as possible.

It is also possible to make at least one of the following additional operations of saw timber 1 treatment under the conditions when piling strips 2 are fixed according to the invention. This applies especially to the operations at which there is an influence by chemical or biochemical agents induced on the saw timber 1

This is possible before drying, during the course of drying or after drying.

Example 2

The way of drying of saw timber and device according to figures Fig. 4 to 6 is another example of the invention.

Also here there is a drying device demonstrated which contains also dried saw timber 1 for clearness, in this case the utilization at one piece of saw timber X is demonstrated. All the modular set for drying of saw timber 1 contains a set of individual piling strips 2 in this case which piling strips 2 are parallel. They are laid down on the ground in one line, there is a saw timber 1 piled on this line and there is another line of piling strips 2 laid on it. Only the section of set which contains two piling strips 2 one above another is chosen and demonstrated in the pictures Fig. 4 to 6 for simplicity. Out of them there is a classically constructed simple piling strip 2 without arresting stops 4J5 placed on the top due to the possibility of comparison and a new piling strip 2 construed according to the proposed technical solution is placed on the bottom under it. All the piling strips 2 are made of metal. The bodies of both piling strips 2 in the drawings Fig. 4 to 6 are of a shape and dimensions common in the branch in question, which fact allows the application on the surface of dried saw timber Λ. These are oblong bodies with flat thrust faces 3 for propping of saw timber 1 which are situated on the bodies of piling strips 2 on the opposite side. The bottom piling strip 2 includes a fixed immovable arresting stop 4 welded on at the area of one end, which is left one in the pictures 4 and 5. Within the area of the opposite side of this piling strip 2 there is a movable arresting stop 5 located which is sliding. The movable arresting stop 5 is provided with the force element 6 serving for its forcing down in the direction towards another one of this pair of arresting stops 4,5 which is to the immovable arresting stop 4. In this case the movable arresting stop 5 is created as a part of hydraulic piston which is utilized as a force element 6. The supporting body of the force element 6 is firmly welded on the bottom piling strip 2. Both arresting stops 4_^5 comprise a level pressure face 7 created on them which area is to induce a pressure power on the piled saw timber 1_. Both the arresting stops 4J5 are located on the same side of the piling strip 2 at one of its two thrust faces 3 and their pressure areas 7 are located against each other.

On the top, at the upper piling strip 2 there are pressure elements 11. in a shape of weight laid.

The device allows the execution of the new method of drying of saw timber 1 at which the pressure power is induced on the dried saw timber 1 at least temporarily, for the time of pressure of force element 6 besides the fact that the dried pieces of saw timber I are fixed against warping by the way of loading by the means of application of piling strips 2 on the upper and bottom side of dried piece of saw timber ±. The mentioned pressure power is induced by the force element 6 in the shape of piston which causes forcing the movable arresting stop 5 down to the dried pieces of saw timber ± and at the same time it causes forcing the saw timber to the immovable arresting stop 4. This causes a pressure power inducing in all the distance between the arresting stops 4J>. The arresting stops 4J5 are forced down in the direction against each other by the pressure, their pressure operates on lateral sides of the piece of saw timber ±. This forcing down then lasts during drying as well as during dry shrinkage of the substance of saw timber 1 and it prevents breaking and warping of the substance of saw timber 1_. At this procedure there is also a free space created by application of piling strips 2 along those surfaces of saw timber 1 where there are piling strips 2 found which free space allows discharging of moisture drawn off the saw timber 1 during the drying. The pressing elements V\_ induce an additional pressure by their weight in the direction of gravity due to their position on the top which additional pressure is induced perpendicularly towards the direction of movement of arresting stops 4J5.

Example 3

Best mode for carrying out the invention shows the new method of saw timber 1 drying consisting in a saw timber 1 drying in chock with the help of device according to the drawings Fig. 7 to Fig. 9. It is an example of optimum application of the invention in bulk, especially in industry.

Also in this case there is a drying device demonstrated which drying device contains also dried saw timber 1 for clearness. Also in this case this is a modular set the base of which is created by the quartet of piling strips 2 connected mutually where in each such quartet the piling strips 2 are fixed firmly in a parallel position side by side. There is a section of one quartet of piling strips 2 chosen out of all the set and demonstrated for the purposes of clarification of the disclosure of invention. In this section there are four quartets of piling strips 2 found above each other. All the system consists of such sections of repeated composition.

Individual piling strips 2 are of a shape and dimensions common in the branch in question and they allow to be applied on the surface of dried saw timber 1 They are created as oblong flat rods with flat thrust faces 3 for propping of the saw timber 1 located in an opposite way on the top and on the bottom. The ends of piling strips 2 are welded on the rods which rods are their fixed joints. One of these rods, in the Fig. 7 and 8 located on the left, at the same time creates a fixed immovable arresting stop 4 for the laid saw timber 1 There is a movable arresting stop 5 found in the area of opposite, right ends of piling strips 2 which arresting stop 5 is movable towards the quartet of connected piling strips 2. The movable arresting stop 5 is provided with the force element 6 for its forcing down in the direction to the other one of this pair of arresting stops 4j5 which means to the immovable arresting stop 4.

Both arresting stops 4J5 include a level pressure face 7 which was created on them in order to induce a pressure power on the laid saw timber ±. The pressure face 7 protrudes on the outside periphery of the piling strip 2 on the side where there is thrust face 3 found. Both two arresting stops 4J5 are located on the same upper side of the piling strip 2 which means at the same thrust face 3. Pressure faces 7 are located against each other at these arresting stops 4,5.

Each of the quartets of the piling strips 2 demonstrated in the figures Fig. 7 to 9 which are firmly and immovably connected to each other in mutual parallel position with a gap between them creates an independent detachable body. Due to this fact it is possible and also practical that this quartet of piling strips 2 disposes of created common arresting stops 4,5 and that in its gap there is a force element 6 found, in this exemplary embodiment it is a piston. The force elements 6 in a shape of piston are firmly fixed by the means of weld on the immovable supports 12 of the pistons which are welded on the ends of piling strips 2. The force elements 6 have their terminal parts located in the gaps between the piling strips 2. The fixed connecting joints of piling strips 2 are used as supports 12 of the pistons on one of their side, it is on the right in Fig. 8. The process of drying is implemented in the following way. Before drying there is the first layer of quartets of piling strips 2 placed on the bottom first, parallelly side by side. The saw timber 1 is piled on it in line within the space between arresting stops 4,5. There is another layer of the quartets of piling strips 2 and another layer of the saw timber 1 piled. This procedure is constantly repeated until all the chock of saw timber 1 is piled. The dried pieces of the saw timber 1 are fixed against warping this way with the help of application of piling strips 2 on the two opposite sides of the areal planar formation of each layer of dried pieces of the saw timber 1, here it is on the top and on the bottom as well. By the way of application of quartets of piling strips 2 there is a free space concurrently created along those surfaces of the saw timber ± where there are piling strips 2 found through which free space there is moisture which was drawn off the saw timber 1 discharged during drying. During the drying there is a pressure power also induced on the saw timber 1 at least temporarily which pressure power is induced by mechanical means in the form of arresting stops 4J5 and force elements 6. The force elements 6 in the form of pistons can be in active operation for a certain period of time or during all the time of drying or they may operate for example by the way of pulses. Their activity causes a pressure of the arresting stops 4J5 on the dried pieces of saw timber 1, namely in opposite direction, here on the lateral sides from the right and from the left which means on other two opposite sides of areal planar formation of each of the layers of the saw timber I when compared with the ones on which there are piling strips 2 found. The pressure power is induced in an intensity pursuant to the size and number of pieces of saw timber 1 in such a way that it is sufficient at least to force the adjacent pieces of saw timber 1 down to each other and to keep them side by side as tightly as possible and without creation of recognizable gaps even after volume reduction caused by dry shrinkage of wood substance. In the Fig. 8 there is a direction of material flow indicated by two arrows which flow is achieved as a consequence of artificially induced force influence by force elements 6 and pressure elements V\_. After exsiccation the grids created of the piling strips 2 are disassembled into individual quartets and they are laid aside on a suitable place or they are directly dislocated on a new damp saw timber 1 for other utilization while the dried saw timber 1. is passed on other treatment or on sale. It is purposeful to leave the piling strips 2 on the saw timber I as long as possible. It is also possible to leave them on the saw timber 1 also after the exsiccation to prescribed moisture and under these conditions to make at least one more of the subsequent operations of the treatment of saw timber 1 after drying. This applies especially to the operations during which there is an influence on the saw timber 1 induced by the way of chemical or biochemical agents. Then the drying may be eventually implemented preferably again without disassembly during which drying the saw timber 1 is again exposed to the influence of pressure force which is induced in the same way.

The demonstrated examples of carrying out do not limit the coverage of technical solution anyhow; it is possible to combine and to modify the proposed new attributes further. It is for example possible to utilize a different number of connected piling strips 2 instead of their pairs or quartets, or to create all the grid out of them and it is also possible to utilize other force elements 6 and the like. Such other variants are explanatory demonstrated by other drawings of other devices on Fig. 10 to 12. Fig. 10 illustrates a device with piling strips 2 connected one above another by the means of articulated joints 13 with force elements 6 in the form of pistons, at Fig. 11 it is by the means of pivoted arms |4 with force elements 6 in the form of pistons. For example in the Fig. 10 and 11 there are movable arresting stops 5_created at both ends of piling strips 2 with the help of the above mentioned system. In the Fig. 12 there is used the frame construction 15 in which there are piling strips 2, movable arresting stop 5, force element 6 as well as pressure element H found. The force element 6 is attached to the frame construction 15.

Claims

C L A I M S

1. Method of saw timber drying providing the fixation of dried pieces of saw timber 1 against warping by loading, which is realised by adding the piling strips (2) to the two opposite sides of the dried pieces of saw timber (1 ) and at the same time a free space is created along these surfaces of saw timber (1) where there are the piling strips (2) found, through which free space there is a moisture drawn off saw timber (1) discharged during the drying, while besides influence of the weight induced by gravity and weight of the saw timber (1) and of piling strips (2) there is a pressure power induced on the dried saw timber (1 ) at least temporarily during drying which pressure power, characterized by that this pressure power is induced by mechanical means, by their pressing to the dried pieces of saw timber (1), namely against each other, which is implemented at the two other opposite sides of the saw timber (1) than where are piling strips (2) found.

2. Method of saw timber drying according to claim 1 , characterized by that the dried saw timber (1) is first piled at least in one layer creating an areal planar formation, afterwards there are piling strips (2) applied on the planar surfaces of this layer which piling strips (2) create a free space along these planar surfaces, whereupon, during drying, there is a pressure power induced to the lateral surfaces of this layer from the opposite sides and simultaneously in the direction of the course of planar surfaces of the layer, which power is induced by mechanical means, namely continuously or interruptedly for a certain period of time, while pressure power is induced in the intensity sufficing at least to force the pieces of saw timber (1 ) to each other and keep them without creation of gaps even after their reduction caused by dry shrinkage.

3. Method of saw timber drying according to claim 2, characterized by that the dried saw timber (1) is piled in chocks which means in layers creating areal planar formations situated in parallel levels above each other, which layers are interlaid by piling strips (2), whereupon during the course of drying there is a pressure power induced counterly by the mechanical means, not only to the lateral sides of these layers but besides that also to the planar surfaces of the layers, perpendicularly towards the pressure power influencing in the direction of the course of planar surfaces of layers.

4. Method of saw timber drying according to claims 1 to 3, characterized by that during the influence of pressure power, induced in the same way, there is at least one of the operations of treatment of saw timber (1) made in the situation when the piling strips (2) are added to the saw timber (1) at which operation there is an influence by chemical or biochemical agents induced on the saw timber (1 ).

5. Device for saw timber drying by the method according to some of claims 1 to

4, containing at least two piling strips (2) for adding to the surface of the dried saw timber (1), where these piling strips (2) are in the form of an oblong bodies with flat thrust faces (3) for propping of the saw timber (1), which thrust faces (3) are located on piling strips (2) in the opposite sides, characterized by that at least one piling strip (2) is provided with the pair of arresting stops (4,5) situated in the area of its opposite ends, with at least one of these arresting stops (4,5) in movable form, where the movable arresting stop (5) has slide gripping towards the piling strip (2) and is provided with at least one force element (6) for its pressing to the second one of this pair of arresting stops (4,5).

6. Device for saw timber drying according to claim 5, characterized by that all its arresting stops (4,5) comprise at least one level pressure face (7) for inducing pressure power to the piled saw timber (1 ), which level pressure face (7) protrudes on the outside periphery of the piling strip (2), on the side where it has its thrust face (3), where at least two arresting stops (4,5) of one piling strip (2) are located on the same side of the piling strip (2), at the same thrust face (3), and their pressure faces (7) are situated against each other.

7. Device for saw timber drying according to the claims 5 and 6, characterized by that at least two piling strips (2) are connected firmly, immovably, to each other in a parallel mutual position, with a gap between them, where this connection is realised through the fixed immovable joints, and where at least one pair of adjacent piling strips (2) has common arresting stops (4,5) and there is the force element (6) or at least its part found in its gap.

8. Device for saw timber drying according to claim 7, characterized by that force element (6) is created like at least one spring which is fixed by at least one its end to a movable arresting stop (5).

9. Device for saw timber drying according to claims 5 to 7, characterized by that force element (6) is created like the articulated joint (13), pivoted arm (14) and/or piston, which has its movable part fixed to the movable arresting stop (5).

10. Device for saw timber drying according to claims 7 to 9, characterized by that movable arresting stop (5) is provided with at least one setting element (8) for keeping its position in stretched state.

11. Device of saw timber drying according to claims 7 to 10, characterized by that between the opposite ends of the piling strip (2) there are at least two movable arresting stops (5) created at the same thrust face (3), where each of the movable arresting stops (5) is connected to a force element (6).

12. Device for saw timber drying according to claims 7 to 11 , characterized by that piling strips (2) are created as rods having tetragonal cross-section and these piling strips (2) are provided with arresting stops (4,5) in the form of bodies which are also created as rods having tetragonal cross-section.

13. Device for saw timber drying according to claims 5 to 12, characterized by that piling strips (2) are situated in the chock, where piling strips (2) are arranged in a line where they are parallelly towards each other, and that between their pair of arresting stops (4,5) there is at least one layer of saw timber (1) piled which layer creates an areal planar formation here, where such lines of piling strips (2) provided with the layer of saw timber (1) are created at least two, one above another, and they are arranged so that the areal planar formation of saw timber (1) is propped from the top and from the bottom on thrust faces (3) of piling strips (2), and the level pressure faces (7) of arresting stops (4,5) are propped on the lateral sides of the planar formation.

14. Device for saw timber drying according to claim 13, characterized by that at least some piling strips (2) from the ones, found side by side and/or above each other, are interconnected together, of which the piling strips (2) found side by side are interconnected together firmly, immovably.

15. Device for saw timber drying according to claim 14, characterized by that at least some piling trips (2) are provided with severable interconnection, by the means of connecting elements for a detachable joint.

16. Device for saw timber drying according to claims 13 to 15, characterized by that the chock is provided with at least one pressure element (11) situated on its surface, namely in a functional position for inducing the pressure perpendicularly towards the direction of the movement of arresting stops (4,5).

17. Device for saw timber drying according to claims 15 to 16 characterized by that piling strips (2), movable arresting stop (5) and force element (6) are situated in a frame construction (15).