WOOD PRODUCT OF MASSIVE WOOD, FLOOR COVER AND METHOD AND EQUIPMENT FOR THE PRODUCTION OF WOODEN ELEMENTS

Abstract: Objet of the invention is a wood product, method and equipment for a production of a wood product (100), preferably a floor element, such as parquet. Object of the invention is a floor surface cover. The wood product includes flat surfaces and longitudinal and end sides (D1, D2, D3, D4). At least one groove (J2, U, U1, and U2) is formed into the longitudinal side of the wood product. Characteristic to the invention is, that a surface layser that is harder and tighter than internal wood is formed onto the wood product by hot pressing, very preferably saw material or saw blank, which surface layer extends over the flat surface of the wood product to at least one longitudinal side, and that selectively: continuity of the hot pressed surface layer is cut by the groove (J2) or tongue joint (J1) locating in the longitudinal side and/or bottom surface of the wood product; or the hot pressed surface layer extends essentially as continuous over the flat surface of wood product, longitudinal side of wood product and border or opposite surface of at least one groove or tongue joint locating in the longitudinal side.

Description: Wood product of massive wood, floor cover and method and equipment for the production of wooden elements The invention relates to a wood product, preferably a floor element, of massive wood according to the preamble of claim 1, and a method according to the preamble of claim 12 and an equipment according to the preamble of claim 28 for the production of wood products. Object of the invention is also a floor cover according to the claim 36. Massive wood floor products according to the prior art and their match-boarding equipment are manufactured after drying of saw material or saw blanks with the help of turning. Hereunder the wood product of massive wood will mean first and foremost floor element, which is usually floor plank, floor board or lath parquet made of raw or dried saw material or massive wood blank. According to the first aspect of the invention the object is to create a new type of wood element with improved durability. According to the second aspect of the invention the object is to improve the straightness of flat and edge surface of the wood product, preferably of the floor element compared to existing solutions and qualities of stiffness and flexural strength. According to the third aspect of the invention the object is to create wood product, preferably a floor element, in which surface layer a surface tightened and hardened in relation to the wooden interior of wood element has been produced with hot pressing, which extends as continuous over at least the wood element until visible flat surface and longitudinal side contacting the flat surface so that continuity of the tightened and hardened surface on the side surfaces can be cut by matched tongue or groove or any other groove made to the longitudinal side. According to the fifth aspect of the invention the object is to reduce drying ne- cessity of saw material or saw blanks and facilitate essentially the manufacturing of completed massive wood product directly from sawing-ready saw material or saw blank. According to the sixth aspect of the invention the object is to create a floor cover material, into which floor-heating could be integrated. These objects and mainly the objects of first - fifth aspect of the invention have been achieved by the wood product both equipment and method for the production of the wooden product mentioned in the beginning, the essential features of which are specified in the accompanying set of claims, whereby the essential features of the wood product are specified in the characterising part of the independent claim 1 and in the dependent claims 2-11, the essential features of the method are specified in the characterising part of the independent claim 12 and in the dependent claims 13-27, and essential features of the equipment are specified in the characterising part of the independent claim 28 and in the dependent claims 29-33. The objects will be realised also by the floor cover according to the invention, the essential features of which have described in claims 34, 35 and 36. In general it is characteristic to this invention that to the wood product, very preferably by hot pressing saw material or saw blank, has been formed a surface layer, which is harder and thicker than internal wood of the wood product and extends from flat or usable surface of the wood product until at least one longitudinal side of the wood product and that the continuity of the hot pressed surface layer of the wood product is interrupted selectively by a groove located on longitudinal and/or bottom side of the wood product or the hot pressed surface layer extends as continuous over the flat or usable surface of the wood product, longitudinal side and the surface on longitudinal side limiting at least one groove or its reverse side. Tongue and groove joint of massive wood floor element can be formed either as traditional solution with one match or according to the invention with two matches or separate floor-heating or joint elements. In case of massive wood floor element deepened groove described in the invention or deepened groove in bottom flat sur- face of floor element can be used, with which a channel can be formed in floor cover consisting of floor elements, which will enable to install floor-heating in the floor and guarantee large heat transmission surface between floor element and heating element. Hence in accordance with the invention the application includes tongue and groove joint means and a tongue and groove joint by means of the same; forming tongue and groove joint to a floor element by means of a floor-heating or another joint element of the tongue and groove joint; deepened groove/-s for an installation of floor-heating; a floor cover, such as board floor, parquet or other floor cover that is consisting of wood products according to the invention., provided with an integrated floor-heating. It should be noticed that the application also concerns invention to provide originally completed floor elements with deepened grooves according to the invention for installation of a floor-heating element and hence to integrate a floor cover and a floor- heating element. This application also describes a new production method of massive wood product with or without groove and tongue, preferable floor element. Wood product with groove and tongue is a massive wood floor element, which includes preferably groove and tongue joint means, i.e. at least one tongue or groove, floor element on longitudinal side and floor element, in which groove and tongue joint means are also suitably located on both shorter end sides of the floor element. Thereby in groove and tongue joint the second longitudinal side of massive wood floor element, which includes one or according to the invention two grooves, is female longitudinal joint side and correspondingly the other longitudinal side, which includes one or accord- ing to the invention two external edges or joints, is male longitudinal joint side. The other end side can include correspondingly one or two grooves, or it can be end side with female joint; the second end side may include one or two external edges and be male end side. Massive wood floor element with groove and tongue is also meant according to the invention: floor element with single groove, which has at one longitudinal side a canal formed by deepening the groove, floor element with one tongue or extension edge, which has at a bottom flat surface a canal formed by turning, floor element with double joint means, which has at both longitudinal sides a deepened groove, and floor element without actual joint means, which elements are jointed together by installation of special joint or floor-heating element into the canal formed at the deepened grooves of the adjacent elements. According to the invention specified in this application massive wood floor element with significantly improved characteristics will be formed of fresh saw material or saw blank directly upon hot pressing. According to the invention the saw material or saw blanks preliminarily profiled in necessary amount according to the product will be placed into hot press and at hot pressing floor elements with flat and straight edge will be produced from sawn material or saw blank, which groove and tongue joints can be formed through hot pressing and/or on lathe during preliminary processing before hot pressing and/or at post-processing, turning elements after hot pressing. Suitable floor-heating elements include installation possibility of floor-heating and of other qualities completed massive wood floor elements. According to the invention the temperature within the range T = 150-220 °C will be produced in saw mate- rial or saw blank. Pressing pressure, which is directed onto the surface of saw blank, is then within the range P = 10-15 kp/cm 2 and time of processing remains within the range H = 2-5 h. During pressing heat is produced in saw material or saw blank and due to the temperature the surface layer can be formed, tightened and hardened. Treatment of surface layer of floor element, formed in such way, will guarantee higher compaction degree and hardness, which will be equal to that in internal layers of massive wood. Hot pressing is carried through according to the invention with fresh (possible also dry) saw material or saw blank, which can be pre-profiled in case of necessity. Pref- erably sawn pre-profiled saw blank will then pass during the process into drying, pressing temperature treatment and/or profiling phase taking place simultaneously in the same machine. Pre-profiling of saw material or saw blank carried out will facilitate thermal treating and profiling, which will take place during hot pressing, necessary for the desired end product. After pressing the saw blank is already essentially in the state of a completed floor element of massive wood. According to the inven- tion grooves or extension edges of longitudinal and/or end sides of the floor element can also be made to a blank of a floor element by means of a turning postprocessing. End product corresponding to the invention, which is dried, thermal treated and hardened both compacted from the surface thereof by means of hot pressing will retain its dimensions and state even in the most differing conditions better than an end product manufactured by a traditional way, i.e. by drying saw material or saw blank and by a turning post-processing. According to the invention also such tools are used, which are placed before hot pressing against flat surfaces or both longitudinal sides of saw material or saw blank. According to one realisation method of the invention pressing means will include such formation method of joint and groove, that through direct hot pressing joint means, i.e. necessary joint grooves and tongues or extension edges and needed deep- ened grooves are formed on longitudinal sides of saw material or saw blank. Hence for pressing of the second longitudinal side the pressing tools of such second longitudinal edge include first pressing tool elements, first groove and tongue joint tool elements and deepened groove tool elements: and for pressing the other longitudinal side the second groove and tongue joint tool include: second pressing tool elements, second groove and tongue joint tool elements and deepened groove tool elements. It should be noted that when deeper grooves is desired to be formed in the longitudinal edge it is preferred to use for the formation of the grooves a preliminary turning processing before hot pressing, whereby it is additionally preferred to profile by hot pressing the groove, tongue or extension into a desired final dimensions and/or an after turning following the hot pressing, by which after turning it can also be performed a final dimensions of the groove or extension edge. According to the invention, in case of more preferred method groove and tongue joint means will be formed also in both short ends of floor element, i.e. necessary joints or extension edges in one end and necessary grooves in the other end. Pressure means of hot pressing will press only saw material or saw blank surface. In such case wood will soften and its binding substances will melt and the wood will be pressed together from surface layer, at the same time, when crimping of wood will decrease towards the midpoint of the blank. While the floor element will according to the invention harden and thicken significantly only from surface at hot pressing and/or profiling: inside the element will remain an increasing discharge space for extruding water and water vapour due to propagating press and heat, which will contribute essentially to successful completion of the process, size, stiffness and flexural strength of the element will not decrease, as cross section profile of saw material or saw blank will not change essentially during hot pressing, hardness and compaction of element surface is maximum, because higher pressing force can be used due to the counter pressure that increases towards centre (counter- pressure of colder wood and water vapour forced to extrude), need for pressing force and temperature are minimal and massive wood floor element will gain the greatest possible surface hardness, surface compaction, humidity retention, stiffness preventing deformation and flexural strength. In such way according to the invention a new type of massive wood floor element with very high quality is provided by hot pressing and especially by using pressure parts not only on flat surfaces, but also for at least pressing thermal treatment and/or forming of longitudinal sides and their grooves and tongues as well as deepened groove elements. In a hot pressing equipment according to the invention saw material or saw blanks are loaded between press plates of a multi-layer hot plate press side by side and one after the other. For pressingly thermal treating and flatting sides of a floor element of massive wood and selectively thermal treating and/or profiling side groove and tongue elements or side tongue means and deepened grooves, preferably narrow and very preferably profiled, pressure parts, so-called hot plates, running in the direction of the longitudinal sides of the saw material or saw blanks, are placed before hot pressing between the saw blanks. At the selection of vertical size of pressure parts the height of longitudinal sides of hot pressed products will be the thickness of desired end product. Side profiled pressure parts with length equal to the width of the element, corresponding with thickness, can also be placed in both ends of floor element for pressingly thermal treating and/or forming the ends and/or end tongue joints and end groove joints. Additionally the pressing equipment according to the invention includes: first and second force means, placed preferably in vertical direction of hydraulic cylinder or geocentric adhesion and two horizontal directions endwise in relation to each other, which pressing force can be directed onto saw material or saw blank in vertical as well as horizontal direction and Temperature rising elements placed preferably so that corresponding heating devices or circulation pipes of heated air are located not only on flat surfaces of saw material or saw blanks, but also in pressure parts of longitudinal sides of saw material or saw- blanks and small pressure parts of short side surfaces are heated sufficiently through surrounding large pressure parts with heat circulation. When pressing and heating is located precisely in the tools, which upon pressing will cause thermal treatment and/or forming of surfaces, tongues, grooves and deepened grooves, pressure and temperature can be directed directly onto the surface of pressed saw material or saw blank so that the desired chemical and physical changes for forming, compaction and hardening of the surface will take place only in surface layer. Charging part is preferably formed of saw material or saw blanks, which charging part means blanks laid in parallel and sequence in several layers. Hence the pressing and thermal treating is performed simultaneously for a large amount of saw material or blanks. There are in every layer own pressure tools necessary to make or pressingly thermal treat a tongue means / a deepened groove. Massive wood product according to the invention has achieved, among others, following advantages: wood product is a profiled massive wood floor element, which is by hot pressing thermal treated and/or essentially finished, external surface of the wood product is composed of compacted wood material, which is glued, with adhesive substances of its own, external surface of the wood product is compacted really tight and hard wood material, wood product has straight flat surface and side, humidity deformation and other deformations are minimal, need to use chemicals is minimal, rot resistance and heat conduction are improved, fire resistance is improved, as wood product of pressed massive wood has low inflammability, wood product is a massive wood product in one piece. Flexural strength is high, which enables to provide thin product thickness. According to the invention it is also essential to massive wood floor element that it can be a double joint floor element and a floor element, which may include a deepened groove extending in both longitudinal sides or a deepened groove extending in only one longitudinal side or a canal groove extending in the flat downwards facing surface thereof, the groove/-s or canal forming a canal for installing a floor-heating element into a floor cover constructed from floor elements. In addition to that it is possible to produce above described or any other floor element, which is turnable, i.e. both flat surfaces thereof can be used as a floor surface. In addition to a double joint elements it is also characteristic, that two completely ready-made floor ele- ments can be produced when such element is sawn into two pieces in horizontal direction, the flat surface to be a utility side and side surfaces of which are of compacted massive wood and which can also include tongues, grooves and deepened grooves. Below the invention has been described by disclosing at the same preferred floor element solutions, to which, however, the invention is not intended solely to be limited. Figure 1A describes the method of production of massive wood floor element from saw blank according to the invention. Figure IB describes production of massive wood floor elements performed in practise, where saw blanks are placed in hot press in parallel and one after another in several layers. Figure 2A describes massive wood floor element manufactured with the method according to the invention. Figure 2B describes schematically tight and hard surface layer f of massive wood floor element, manufactured with the method according to the invention. Figure 2C massive wood floor element manufactured with the method according to the invention, where joints are located in longitudinal sides of the element as well as in both ends. Figure 2D describes massive wood floor element given in figure 2C from the direction of the arrow Figure 3A describes massive wood floor element, which has been manufactured from the element described in figure 2 A by deepening the joint groove in the latter. Figure 3B describes massive wood floor element, which has been manufactured from the element described in figure 2C by deepening joint groove. Figure 4A describes massive wood floor element manufactured with the method according to the invention, where actual joint is missing or which both longitudinal sides have deepened groove. Figure 4B describes elements given in figure 4A, which have been placed together for jointing; deepened grooves of massive wood floor elements complement each other and form a relatively wide canal. Figure 4C describes pressure tools necessary for the formation of long lateral sur- faces of massive wood floor element given in figure 4A. Figure 5A describes massive wood floor element manufactured with the method according to the invention, which both edges have elements for the formation of so- called double joint. Figure 5B describes joint pressure tools for the production of floor element described in figure 5A. Figure 6A describes massive wood floor element manufactured with the method according to the invention, which has deepened grooves in addition to double joint means. Figure 6B describes two massive wood floor elements connected to each other, given in figure 6A, where deepened grooves of the elements complement each other and form a relatively wide canal. Figure 6C describes pressure tools for the formation of joint and deepened grooves of massive wood floor element given in figure 6A. Figure 7A describes floor element manufactured with the method according to the invention, in which bottom flat surface canal groove has been made. Figure 7B describes floor element with main joint given in figure 7 A. Figure 1A describes schematically the production of floor element 100, hot pressed from each side, according to the invention from saw blank 200. In this application a floor element 100 of massive wood means floor plank, floor board or parquet, which has been made of saw blank 200 and which surface layer has been compacted and hardened during hot pressing. Joints Ji and joint grooves J 2 as well as other grooves Ui and U 2 of longitudinal sides Di and D 2 as well as end sides D and D 4 of floor element complying with the invention, contacting with flat and bottom surfaces, have been manufactured selectively: by preliminary turning before a hot pressing, whereby final form of tongues and grooves has been achieved also with hot pressing or post-turning after hot pressing, by turning after hot pressing, whereby final form of tongues and grooves has been achieved by this post-turning, and/or essentially by hot pressing, whereby floor element has been manufactured from saw blank directly to an essentially ready-made floor element by hot pressing. According to the invention saw blank 200 has been made of saw material. This involves both flat sides, longitudinal sides Di and D 2 and end sides D and D 4 . Pref- erably saw blank already during a sawing phase is pre-profiled if necessary according to comply with a product, whereby the same may include preliminary groove and tongue joint means, i.e. one or two preliminary extension edges and grooves both pre-deepened grooves. Such a possible pre-pro filing of saw blank is not pre- sented in the figure. According to the invention at least one saw blank 200, which is composed of massive wood, is placed into a pressing equipment between an upper pressure plate 12a 1 and lower pressure plate 12a 2 thereof. Between the mentioned plates 12a 1 and 12a saw blank 200 are placed to be surrounded from all sides, at least from longitudinal sides D) and D by tongue and groove joint formation tools, i.e. pressure tools l lai and l la . When completed joint grooves and other grooves necessary for completed product are profiled in saw blank 200 during hot pressing, such thermal treating means and/or groove and tongue joint formation means 11 are used for the pressing of longitudinal sides Di and D 2 , which form an extension element of groove and tongue joint by profiled pressure tool 1 lai on one longitudinal side Di of the saw blank and which form groove element of groove and tongue joint by pressure tool 1 la 2 on the other longitudinal side D of the saw blank. It is essential to note that in pressure tools of longitudinal sides O \ and D 2 it is not inevitable according to the principle of the invention to form extension or groove elements of longitudinal sides Di and D 2 , but according to the invention by these pressure tools can also selectively: pressingly thermal treat grooves and extensions formed by turning; or pressingly thermal treat only a flat surface of the longitudinal side. Preferably one can use at both shorter ends D and D 4 of saw blank 200 the pressing thermal treatment tools and/or end side pressing tools 11 for the formation and/or pressingly thermal treat groove and tongue joint means, preferably it is used at one short side D 3 forming the extension element of groove and tongue joint or for pressing thermal treating the same by the pressure tool 1 lai', and at the other short side D 4 is used the pressure tool 1 la ' which forms the groove element of groove and tongue joint or pressingly thermal treats the same. In the figure is described only profile that forms a saw blank 200. In practical situation there are several saw blanks located side by side and one after another, whereby at an opposite side of the tool there is a form that pressingly thermal treats and/or profiles the side of the adjacent saw blank. The figure 1A describes schematically heating devices 13 located in upper pressure plate 12aι and lower pressure plate 12a as well as in pressure tools 1 lai and 1 la of longitudinal side. Electrical heating device is used, which generates sufficiently high temperature or oil canals, through which hot oil is led, in order to achieve the effect necessary for thermal treating of the surfaces of saw blank 200. Means generating pressing effect are marked with reference number 140 and 130. Pressing cylinder 140aι is used preferably, which generates pressure in upper pressure plate 12aι and lower pressure plate 12a 2 , as well as pressing cylinders 130b 2 and 130b 3 , which gen- erate pressure in pressure tools 11 ai , 11 a 2 , 11 & \ ' and 11 a '. In a first stage flat surfaces of saw blanks are pressed straight and to the thickness specified by pressure tools. Most of the water discharges during this stage. Then in the width direction of the blanks the sides of the blanks are pressed straight and at the same their widths are pressed to correspond to the length of the pressure parts llai ' and lla 2 ' of the groove and tongue joints while the pressure parts of the longitudinal sides pressingly thermal treat the sides of the blank and/or form and/or in addition to the side surfaces pressingly thermal treat also groove and tongue joint means at both longitudinal sides of the blank, i.e. extension edge/edges J t or joint tongue and joint groove/grooves J 2 , and/or grooves Ui and U 2 having the form of deepened groove U. Finally, if necessary, longitudinal pressing of saw blanks is performed with pressure parts l lai ' and l la 2 ' of blank ends, which upon pressing will treat thermally the ends of saw blanks and selectively form end groove and tongue joint elements in them, i.e. extension edge/edges Ji or joint tongue and joint groove/grooves J 2 . In order to discharge vapours, to improve pressing thermal treatment and to improve profiling series of the press is repeated several times according to the necessity. As a last stage is performed a cooling of saw blanks while pressing continues below 40 °C. Hereby in a pressing temperature, which is between 150 - 220 °C, melted adhesion materials will stiffen. Pressed, essentially completed floor element of massive wood will remain in the desired form after press is opened. Figure IB describes several saw blanks 200 placed on each other. Layers are marked in the figure as c ls c 2 , c 3 .... Each layer ci, c 2 ... contains several saw blanks in paral- lei and one after the other in pressed condition and between them there are, according to the invention, pressure tools 11 meant for hot pressing and/or forming of joint/deepened groove. As according to the invention it is not inevitably necessary to form final shape of the longitudinal side of floor element by the pressure tool, such final shape of pressed floor element has not been presented in the figure neither there is presented a corresponding form profile of pressure tools 11. Height H of pressure tools 11 is preferably just the height, to which thickness the board floor blank 200 is desired to be pressed in order to form a hot pressed floor element 100 of massive wood. So according to the invention pressing force is generated vertically and in right angle in relation to it, i.e. horizontally. Pressing force is brought against longi- tudinal sides in horizontal direction with pressure tools l lai, Ha 2 , which will provide to the longitudinal sides D ls D of floor element of massive wood the pressing thermal treatment, the side straightness, the desired width, which corresponds to the pressure part 11 of the end, to the joint groove, to the joint tongue, to the deepened groove. One preferable embodiment is naturally also such, wherein pressure tools l lai' and l la ' are used in a horizontal pressing direction in order to pressingly thermal treat and/or by hot pressing form both shorter end sides of the saw blank 200. Following processing is used according to the invention. Temperature T is within the range of 150-220 °C. Pressing pressure P is within the range of 10-15 kp/cm 2 . Total pressing time H is within the range of 2-5 h. The application includes also solution, wherein pressing of joint, joint groove and/or deepened groove has been performed partially, with pressure tools, which do not correspond to the shape of end product. Hence is achieved all essential and desired special features of floor element, such as side straightness of longitudinal sides and sufficient thermal treatment of groove and tongue joint means and deepened groove. Hence post-turning provides the final exact profile of floor element preferably after hot pressing. In all cases it is possible according to the invention to perform finish polishing of floor element, where will take place minor accommodating of the profile, which was provided by pressing, into end product. In order to make hot pressing process, thermal treatment by pressing of product pro- file and its surfaces successful in a desired way there is a reason to comply details of product profile, pre-turning profile and pressure tool profile with the product. The application does not describe possible pre-turning tools or profiles neither detailed and precise pressure tool and product profiles. In the Figure 2 A is presented a floor element 100, which is provided by a method described in the figures 1A and IB. In the floor element 100 of massive wood presented in the figure 2 A the joint element Ji, J has been formed on both longitudinal sides Di and D 2 of the floor element of massive wood. In the embodiment presented in the Figure 2A both end sides D and D 4 are presented without groove and tongue joint means Ji and J 2 . In the Figure 2B is presented schematically a compacted and hardened surface layer f in the floor element of massive wood with groove and tongue joint means, pro- duced by the method according to the invention. From the standpoint of the invention it is not most essential, whether the groove and tongue joint means are provided directly by hot pressing or if a pre-turning e.g. during sawing preceding the hot pressing and/or a post-turning after the hot pressing is used for their production. So according to the invention, using heat production and surface heating in the hot pressing phase, the above mentioned compacted and hardened layer is produced on the surface of massive wood floor element and at the same time it is possible to pressingly thermal treat and or profile the groove and tongue joint means Ji and J 2 and/or grooves Ui and U with the shape of deepened groove U in longitudinal sides Di and D of massive wood floor element, using pressure tools 11. If pressing thermal treatment according to the invention is directed into pre- turned joint groove or another groove it accomplished the advantage that the border surface of that groove will harden and compact. Independent of the fact, that whether pre-turning is used or not, pressure tools will perform the formation and/or pressing thermal treating of groove and tongue joint means in desired form and dimensions of essentially completed floor element. According to the invention also such an embodiment is possi- ble, wherein groove and tongue joint means or their pre-blanks are formed during hot pressing stage into the saw blank 200, which does not include pre-sawn grooves and extension edges for the groove and tongue joint. If during hot pressing the pre- blanks of the groove and tongue joint means are performed, the groove and tongue joint means are formed and deepened to final dimensions after hot pressing by post- turning. In the Figure 2C is presented a floor element 100, which corresponds to the element of the figure 2A, in which element a completed floor element of massive wood is manufactured by hot pressing horizontally and vertically, whereby it includes groove and tongue joint means Ji, J 2 on all sides Di, D , D 3 and D 4 thereof. In the Figure 2D is presented a floor element massive wood of the figure 2C in the direction of arrow Ki of the figure 2C. Figure 3 A is described a floor element 100, which has been formed from the element of the figure 2A by deepening the groove and tongue joint groove J 2 on the side sur- face thereof to function as a U shaped deepened groove Ui and U 2 , which forms a canal necessary for installation of floor-heating element. Hereby it is preferable according to the invention that cross section or external circumference profile of floor- heating element will correspond essentially to the shape of cross section profile of the deepened groove U receiving the same whereby the heat transmission surface between heat element and opposite surface of deepened groove will be as large as possible. Heating element installed in such canal according to the invention can be a flow pipe for heating medium, e.g. liquid, air or gas, or an electric resistance. In such a way floor-heating is as-installed and integrated in the floor elements and floor cover constructed thereof and not in floor base construction according to the prior art, which would a more unprefered solution especially when wooden floor covers are used. The floor element 100 described in the figure 3B has been formed correspondingly from the element of figure 2C. Further, it includes an above mentioned end groove and tongue joint means. In the figure 4A is described a floor element 100, which is lacking a true groove and tongue joint means. Sides of the element are provided with a groove Ui, U having a shape of a deepened groove U. In the figure 4B is described elements 100' and 100" according to the figure 4A as- oriented side by side. Jointing the elements together will take place by placing a joint element or more preferably the heating element, which is manufactured for the pur- pose, into a canal formed of the deepened grooves U and Ui of floor. Heating element may include a flow pipe for heating medium, e.g. liquid, air or gas, or an electric resistance. In such a way floor-heating is placed inside the floor elements and floor cover constructed thereof and does not remain in the floor base construction according to the prior art, which is a more unprefered solution especially when wooden floor covers are used. In the figure 4C are described pressure tools 1 lai and l la , by which the deepened grooves on the sides Di, D of the element of the figure 4A are formed and/or pressingly thermal treated. In the figure 5 A is described floor element 100 accomplished of massive wood preferably of full wood by a method according to the invention or by a hot pressing, which element include groove and tongue joint means Ji, J on both longitudinal sides Di, D of floor element so that there are two groove and tongue joint means on either longitudinal side. In the figure there are two extension edges J] or male joints on longitudinal side Di and two grooves J or female joints on the opposite side D 2 . Such a double joint construction provides a very stable jointing. Further, the advantage is that due to smaller size of groove and tongue joint means lower pressing force is needed for forming the same just by hot pressing. Further, the floor element, according to the invention, with double joint of massive wood can be sawn along the midline y shown in figure 5 A so that it will produce two essentially completed floor elements, both of which have flat usable side surface and lateral surfaces of massive wood, which is compacted and hardened by hot pressing. Within the scope of the invention also such an embodiment is possible, wherein double groove and tongue joint elements Ji, J 2 are formed so that one side Di has female and male joints are located respectively and preferably opposite to each other male and female joints on the other longitudinal side D 2 . In the figure 5B are described pressure tools 1 lai, 1 la 2 for the longitudinal side for providing double groove and tongue joint means and/or for pressing thermal treating of longitudinal sides Di, D 2 of the element according to the figure 5 A. As shown in the figure 5B, the profile of one pressure tool l lai comprises grooves Cj, C for formation and/or for pressing thermal treating the male joints Ji according to the figure 5 A on one longitudinal side Di of the floor element 100 and the profile of the other pressure tool 1 la comprise extension edges Cio, C 0 for the formation and/or pressing thermal treating of the female joints according to the figure 5A of on the other longitudinal side D 2 of the floor element 100. Corresponding pressure tools can also be placed at the ends of a saw blank 200 for the formation and pressing thermal treating or hot pressing of groove and tongue joint elements. Further to the so-called double joint shown in figure 5 A, the massive wood floor element 100 according to the figure 6 A include grooves Ui, U having the shape of deepened groove U running in the direction of longitudinal sides Di and D 2 of the floor element 100 of massive wood. The massive wood floor element, according to the invention, which element include the double groove and tongue joint means and deepened grooves, can be sawn along the horizontal midline y presented in the figure 6A so that two essentially completed floor elements are provided therefrom, both of which have flat usable surface side and lateral surfaces of wood material, which is compacted and hardened by hot pressing. Within the scope of the invention such an embodiment is also possible, that the double groove and tongue joint means J 1 } J 2 is provided so that on one side Di are located the groove both the and extension edge and on the other longitudinal side D are located respectively the extension edge and the groove. In the figure 6B are described two massive wood floor elements 100', 100" according to the figure 6A as connected to each other, whereby the deepened grooves U 2 and Ui of massive wood floor elements 100', 100" located side by side are connected with each other and form a rather wide canal. According to the invention flow pipe of heating medium, e.g. air, gas or liquid, or electric resistance heating device can be installed into the canal. In such a way floor-heating is placed inside the floor elements and floor cover constructed thereof and does not remain in the floor base con- struction according to the prior art, which is a more unprefered solution especially when wooden floor covers are used. In the figure 6C are described pressure tools 11a- . , l la for massive wood floor element including the canal element according to the figure 6A. The massive wood floor element has been made like the floor elements described in the previous figures of saw blank, but the pressure tools 11 are formed here so that they include means which form double groove and tongue joint and deepened grooves and/or pressingly thermal treat the same. One pressure tool 1 lai include an edge C , which provide the extension edges Ci, C both the groove Ui, U having the shape of deepened groove U. Correspondingly the pressure tool 11 a 2 to be located along the second longitudi- nal side of the floor element, includes means forming the edge C , which provide and/or pressingly treats thermally the grooves Cio, C 2 o of groove and the tongue joint both the groove Ui, U having the shape of the deepened groove U. The pressure tools 1 lai, 1 la 2 are treated by pressing force achieved by means of a power device, such as power cylinder. Further, heating is provided according to the invention via the pressure tools by heating devices 13 installed therein so, that by simultaneously pressing the surface and/or the groove and/or the extension edge of the saw blank by the heating pressure tool the pressing thermal treating is provided to the mentioned longitudinal sides Di and D 2 of the saw blank. It is possible to install at the ends of the saw blank 200 pressure tools, which provide and pressingly thermal treat groove and tongue joint means corresponding to side groove and tongue joint means. In the figure 7A is described a massive wood floor element produced by splitting the floor element according to figure 2A or figures 5A and 6A, which element has in the bottom flat surface a groove U' formed during a post-processing, which together with a base floor forms a canal necessary for installing a floor-heating element. Into the canal can be placed a flow pipe for heating medium, e.g. liquid, air or gas, or an electric resistance. In such a way floor-heating is placed inside the floor elements and floor cover constructed thereof and does not remain in the floor base construction according to the prior art, which is a more unprefered solution especially when wooden floor covers are used. In the figure 7B is described a floor element according to the figure 7A but provided with groove and tongue joint means of the end. There is a reason to emphasise that basic idea of the invention referred to in this application includes also a solution, that a groove or grooves described in figure 3A or 4A or 6A or 7A or a corresponding, by means of which a floor-heating element is installed, differing of the prior art techniques, directly into a floor cover and not into the base construction of the floor cover, is used as a solution for floor cover, such as floor board, parquet or another floor cover, to be constructed of floor elements by providing the above mentioned floor elements with such a groove or grooves and by installing a floor-heating element into the canal, which is formed inside the floor cover composed of mutually connected floor elements. Heat transmission from the heating element locating inside the surface cover mate- rial cover to the surface cover and further therefrom to room air is more efficient and economical, because: The surface cover does not function as insulation in the extent corresponding to the prior art solutions. Base construction of the floor does not function as a heat accumulator and transmit- ter but functions as a heat insulator. Heat insulating and reflecting material is located under the surface cover and not under the base floor. No qualities of heat conduction and storage are required from the base construction. The need for heat insulation of the whole floor construction is small. Less heat is needed. Heat is transferred more quickly into the room space. Reaction speed to the changes of heat need taking place in the space will increase. Hereby a lower water temperature can be used. Also a lower floor surface temperature is achieved. In addition to that, better efficiency is available for use of soil, air or sun heat. The application includes also solutions, that double groove and tongue joint de- scribed in figure 5A or 6A or a corresponding, differing from the prior art floor cover technology, preferably a double groove and tongue joint, or another preferable groove and tongue joint provided by using the floor-heating element (figure 4B) is used also for a floor surface cover such as floor board, parquet or other floor cover. The invention has been described above only by a way of an example, by means of some preferred examples thereof. This is naturally no intention to limit to any extent the invention to concern these kind of particular examples. Hence, as it is clear to any experienced in the field, several modifications and alternative solutions are possible within the scope of the inventive idea defined in the accompanying claims.

Claims: Claims 1. Wood product (100, 100', 100") of massive wood, preferably a floor element, such as a floor plank, floor board, member parquet, which has flat surfaces, forming usable or cover surface and bottom surface of the wood product and longitudinal and end sides (D \ , D 2 , D , D 4 ), and which wood product has at least one groove or cavity (J 2 , U, Ui, U 2 ) in the direction of the longitudinal side, characterised in, that in the wood product (100) is provided by hot pressing a surface layer, which is harder and tighter than internal wood of the wood product both is essentially compact and which surface layer extends over the flat surface of wood product to at least one longitudinal side (Di, D 2 ) of the wood product (100, 100', 100") and, that selectively: compactness of the surface layer, which is harder and tighter than internal wood of the wood product, is cut by the groove or cavity (J 2 , U, Ui, U 2 ) and/or extension edge or tongue joint (Ji) locating at the longitudinal side of wood product and/or groove or cavity (U') locating at the flat bottom surface, or the surface layer, which is harder and tighter than internal wood of the wood product, extends essentially continuous over the flat surface of upper side and longitudinal side of the wood product and over border or opposite surface of at least one extension edge or tongue joint (Ji) and/or groove or cavity (J 2 , U, Ui, U 2 ) located on longitudinal side. 2. Wood product according to claim 1, characterised in, that the wood product (100, 100', 100") is a floor element, both longitudinal sides (D l 5 D 2 ) of which is provided with two groove and tongue joint means (Ji, J 2 , Ui, U ). 3. Wood product of massive wood according to claim 1 and/or 2, characterised in, that the extension edge or tongue joint (Ji) and/or the groove or cavity (J 2 , U, Ui, U 2 ) is made to at least one longitudinal side (Di, D 2 ) of the wood product (100) selectively: by turning pre-processing before hot pressing; by turning post-processing after hot pressing; and/or by profiling hot pressing during hot pressing. 4. Wood product of massive wood according to claim 1 and/or 2, characterised in, that the extension edge or tongue joint (Ji) and/or the groove or cavity (J 2 , U, Ui, U 2 ) is made to at least one end side (D 3 , D ) of the wood product (100) selectively: by turning pre-processing before hot pressing; by turning post-processing after hot pressing; and/or by profiling hot pressing during hot pressing. 5. Wood product according to any of claims 1-4, characterised in. that a cross section profile of the groove (Ui, U 2 ) of the longitudinal side (Di, D 2 ) of the wood product (100, 100', 100") is formed to correspond essentially to a cross section or exter- nal circumference profile of a floor-heating element to be installed therein. 6. Wood product according to claim 5, characterised in, that the groove (J ) of the longitudinal side (D 2 ) of the wood product (100, 100', 100") is deepened to receive both the floor-heating element having a shape corresponding essentially to the pro- file of the deepened groove (U) and the tongue joint (Ji) of the neighbouring wood product. 7. Wood product according to any of claims 1-6, characterised in. that both longitudinal sides (Di, D 2 ) of the wood product (100, 100', 100") have the groove or cav- ity (Ui, U 2 ) having a shape of a deepened groove (U) j that the joint of the two wood products is formed by placing into a canal formed by grooves (Ui, U 2 ), which have the shape of the deepened grooves (U), of the neighbouring wood products the formed to correspond essentially to the shape of the cross section profile of the canal, which floor-heating element acts then as a joint element, , 8. Wood product according to any of claims 1-7, characterised in, that the wood product (100, 100', 100") is a floor element, both flat surfaces and preferably also longitudinal sides of which have a surface layer, which is harder and more compact than internal wood of the floor element, whereby the floor element is turnable for using the both flat sides of the floor element selectively as the usable or surface side of the floor element. 9. Wood product according to any of claims 1-8, characterised in, that the floor element includes a surface compacted and hardened by hot pressing, which surface extends over the usable surface and both longitudinal sides (Di, D 2 ) of the floor ele- ment either essentially compact or cut by groove/-s or cavity/-ies (J 2 , Ui, U 2 ) and/or tongue joint/-s (Ji) to a base surface of the floor element. 10. Wood product according to any of claims 1-9, characterised in, that both sides of the wood product (100, 100', 100") have groove or cavity (Ui, U ) having the shape of the deepened groove (U) and two groove and tongue joint means (Ji, J 2 ), the channels having the shape of deepened grooves of the neighbouring wood products, which are connected together by the groove and tongue joint, define inside the same the canal, into which the floor-heating element, which is formed essentially into the shape of the cross section profile of the canal, is preferably installable, and that the wood product is splittable along a horizontal midline (y) of the wood product so, that it essentially two completed floor elements are provided, in both of which the surface, which is compacted and hardened by hot pressing, extends over flat surface to side surfaces (Di, D 2 ). 11. Wood product according to any of claims 1-10, characterised in, that the wood product (100, 100', 100") is the floor element, which includes groove (IT) on a lower flat surface or bottom surface, which groove together with a base floor or a heat insulating and reflecting base material of a floor cover installed on a base floor forms the canal so, that the floor-heating element is installable in the said canal be- tween the base floor and floor element, while the bottom flat side of the floor element is in contact with the base floor or the heat insulating and reflecting base material of the floor cover installed on it. 12. Method for providing a wood product (100, 100', 100") of massive wood, pref- erably a floor element, such as a floor plank, floor board, member parquet, which wood product include flat surfaces, forming usable or cover surface and bottom sur- face of the wood product as well as longitudinal and end sides (D \ , D 2 , D , D ), and to which wood product is formed onto at least one longitudinal side (Di, D ) at least one groove or cavity (J 2 , U, Ui, U 2 ) in the direction of the longitudinal side, characterised in, that at least a visible flat surface of the cover surface and at least one lon- gitudinal side (D \ , D ) of saw material or saw blank (200) is hot pressed by a pressure tool (llai, Ha 2 ), whereby a harder and tighter than internal wood both an essentially compact surface layer is formed to the hot pressed saw material or saw blank, which surface layer extends over the flat surface of saw material or saw blank onto the longitudinal sides (D 1 } D 2 ) of the saw blank, whereby selectively: compactness of the surface layer, which is harder and tighter than the internal wood of the hot pressed saw material or saw blank, is cut by an extension edge or tongue joint (Ji) and/or the groove or cavity (J 2 , Ui, U ) locating on the longitudinal side of the hot pressed saw material or saw blank and/or the groove or cavity (U') locating on the flat surface of the bottom side, or the surface layer, which is harder and tighter than the internal wood of the wood product (100), extends essentially continuous over the flat or usable surface of the wood product, longitudinal side and a border or opposite surface of at least one extension edge or tongue joint (Jj) and/or groove or cavity (J 2 , U, Ui, U ) located on longitudinal side. 13. Method according to claim 12, characterised in, that extension edge or joint (Ji) or groove or cavity (J 2 , IT, Ui, U 2 ) is made to the longitudinal side (Di, D 2 ) of the saw material or saw blank (200) selectively: during turning pre-processing before hot pressing; by turning post-processing after hot pressing; and/or by profiling hot pressing during hot pressing. 14. Method according to claim 12, characterised in, that the extension edge or joint (Ji) or groove or cavity (J 2 ) is made to the end side (D 3 , D 4 ) of the saw material or saw blank (200) selectively: during turning pre-processing before hot pressing; by turning post-processing after hot pressing; and/or by profiling hot pressing during hot pressing. 15. Method according to any of claims 12-14, characterised in, that in the method both flat surfaces and both longitudinal sides (Di, D 2 ) of the saw material or saw blank (200) are hot pressed by pressure tools (1 lai, 1 la ), by which pressure tools is carried out the thermal treating of the longitudinal sides. 16. Method according to claim 15, characterised in, that the groove and tongue joint means (Ji, J 2 ) and/or groove or cavity (Ui, U 2 ) and/or deepened groove (U) are profiled and/or hot pressed by the pressure tool (1 lai, 1 la 2 ). 17. Method according to any of claims 11-16, characterised in, that the surface layer that is harder and tighter than internal wood of the saw material or saw blank (200) is formed by pressure tool (l lai, l la 2 ) to the external surface of the groove and tongue joint means (J , J 2 ) and/or groove or cavity (J 2 , Ui, U 2 ) and/or deepened groove (U). 18. Method according to any of claims 15-17, characterised in, that by turning preprocessing or by turning post-processing or by hot pressing by means of the pressure tools (l lai ', 11 a ') to both ends (D 3 , D 4 ) of the wood material or saw blank (200). are formed the groove/-s (J ) and the tongue/-s or extension edge/-s (Ji) of the groove and tongue joint means, whereby are formed the groove/-s (J 2 ) to one end of the saw material or saw blank and the tongue jointZ-s or extension edge/-s (Ji) to the other end. 19. Method according to any of claims 12-18, characterised in, that by the turning pre- or post-processing and/or by the hot pressing is formed the groove (Ui, U ) having the shape of a deepened groove (U) to both longitudinal sides (O \ , D 2 ) of the saw material or saw blank (200), whereby the groove and tongue joint of wood products hot pressed from saw material or saw blank (100, 100', 100") is intended to be made by means of an independent floor-heating element, which is placed into a canal formed by grooves, which have the shape of the deepened grooves, of two neighbouring wood product. 20. Method according to any of claims 12-19, characterised in, that the saw mate- rial or saw blank (200) is hot pressed by means of the pressure tool/-s (1 lai, 1 la 2 ), and that by the pre- or post-processing or by means of the pressure tool is formed: to one longitudinal side (Di) of the saw material or saw blank one or two extension edges (Ji) necessary for the groove and tongue joint and to a second longitudinal side (D 2 ) of the saw material or saw blank one or two grooves (J 2 ) necessary for the groove and tongue joint 21. Method according to any of claims 12-20, characterised in, that the saw material or saw blank (200) is hot pressed by means of pressure tool/-s (1 lai, 1 la ), and that by the turning pre- or post-processing or by the pressure tool is formed: one groove (Ui), which have the shape of deepened groove (U), and two tongue joints or extension edges (Ji) for the groove and tongue joint to one longitudinal side (Di) of the saw material or saw blank and a second groove (U 2 ), which have the shape of deepened groove (U), and two grooves or cavities (J 2 ) for the groove and tongue joint to the second longitudinal side of the saw material or saw blank (D 2 ) 22. Method according to any of claims 12-21, characterised in, that the method includes following steps: the saw blanks (200) are hot pressed flat straight and to the height determined by the thickness of the pressure tools (1 lai, 1 la 2 ), the saw blanks are hot pressed edge straight in the width direction, the widths of the saw blanks are hot pressed to correspond to the length of the end tongue joints, while the pressure parts of the joint grooveΛs (J 2 ) and the groove (Ui, U ) with the shape of deepened groove (U) pressingly thermal treat and/or profile the sides of saw blank and selectively form or profile or pressingly thermal treat by pressing the groove and tongue joint means at both longitudinal sides of the saw blank, i.e. the extension edge/-s (Ji) and joint groove/-s (J 2 ) both groove/-s (Ui, U 2 ) with the shape of deepened groove (U), the saw blanks are selectively hot pressed in longitudinal direction, while end pressure parts (1 lai ', 1 la 2 ) pressingly thermal treat and/or profile the blank and/or form thereto the end groove and tongue joint means, i.e. groove/-s (J 2 ) and tongue joint/-s or extension edge/-s (Ji), and saw blanks are cooled under pressure below 40 °C, whereby in the hot pressing temperature, which is between 150-220 °C, the melted bonding substances of the wood will stiffen and the hot pressed saw blank will form into a form coπesponding es- sentially to the completed wood product, preferable the floor element, which will remain in the desired state after the removal of pressure. 23. Method according to any of claims 12-22, characterised in, that hot pressing is repeated several times in order to release humidity and vapours released from wood material during hot pressing and to improve profiling and forming. 24. Method according to any of claims 12-23, characterised in, that in the method it is used first cylinders (140aι) in a vertical direction for providing of vertical pressure force, and that for providing of horizontal pressure force are used in a horizontal plane second cylinders (130b , 130b ), by means of which second cylinders are influenced to the pressure tools (l lai, Ha 2 , l lai', Ha 2 ') for thermal treating, straightening of all lateral surfaces (D \ , D 2 , D 3 , D 4 ) of saw blanks (200), and for hot pressing or thermal treating or forming of groove/-s (J 2 ) both tongue joint or extension edge/edges (Ji) and/or grooves (Uj, U 2 ) with the shape of deepened groove (U), which is/are belonging to the groove and tongue joint means. 25. Method according to any of claims 12-24, characterised in, that in the method is formed a saw blank (200) from saw material so, that necessary preliminary joint grooves and preliminary joint extension edges both pre-deepened grooves are pre- turned into the saw material, whereby the groove (J 2 ) pre-turned into the saw blank both the tongue joint or extension edge (Ji) and/or the groove (Ui, U 2 ) having the shape of deepened groove (U) is thermally treated and/or profiled by means of pressure tools (l lai, Ha 2 ). 26. Method according to any of claims 12-25, characterised in, that during the hot pressing the pressing force P is between 10-15 kp/cm2, the total pressing time H is between 2-5 hours and temperature T is between 150-220 °C. 27. Method according to any of claims 12-26, characterised in, that the pressing of the groove, cavity or deepened groove (IT, Ui, U ) and the groove and tongue joint means (Ji, J 2 ) is performed partially in order to achieve the desired special features, preferably side straightness of the longitudinal sides (Di, D 2 ) and thermal treatment of the groove and tongue joint means (Ji, J ) and groove or cavity (U, Ui, U 2 ), whereby a final profile of the wood product (100, 100', 100") is made by postprocessing. 28. Equipment for the production of massive product (100, 100', 100") of massive wood, preferably a floor element, such as a floor plank, floor board, member parquet, which includes flat surfaces, forming usable or cover surface and bottom surface of the wood product and longitudinal and end sides (Di, D 2 , D 3 , D ), and to which wood product is formed onto at least one longitudinal side (Di, D 2 ) at least one groove or cavity (J 2 , U, Ui, U 2 ) in the direction of the longitudinal side, characterised of pressure tools (l lai, Ha 2 ) for hot pressing at least flat surface of upper side and at least one longitudinal side (Di, D 2 ) of a saw material or saw blank (200), whereby essentially compact surface layer that is harder and tighter than internal wood will form to the hot pressed saw material or saw blank, which surface layer extends over the flat surface of saw material or saw blank to the longitudinal side of the saw material or saw blank, whereby selectively: compactness of the surface layer that is harder and tighter than the internal wood of the hot pressed saw material or saw blank is cut by an extension edge or tongue joint (Ji) and/or groove or cavity (J 2 , U, Ui, U ), which locates on the longitudinal side of the hot pressed saw material or saw blank, and/or a groove or cavity, which locates on the flat surface of the bottom side (U'), or the surface layer that is harder and tighter than the internal wood of the wood product (100) extends essentially as continuous over the flat surface of the wood product, the longitudinal side and a boarder or opposite surface of the extension edge or tongue joint (Ji) and/or the groove or cavity (J , U, Ui, U 2 ) locating at the longitudinal side. 29. Equipment according to claim 28, characterised in, that the equipment includes, in addition to lower pressure plate (12aι) and upper pressure plate (12a 2 ) for the saw material or saw blank (200) to be hot pressed, pressure tools (l lai, Ha 2 ) for both longitudinal sides (D l5 D 2 ) of the saw material or saw blank to be hot pressed, which pressure tools are pressure tools that pressingly thermal treat the longitudinal sides both form or pressingly thermal treat the groove and tongue joints means (J l s J 2 ) and/or the groove (Ui, U 2 ) having the shape of a deepened groove (U), that the equipment further includes: heating devices (13) for transferring during hot pressing heat into the saw material or saw blank to be hot pressed, and equipment for providing a pressure force, to which equipment includes preferably a first power cylinder means (140aι) for directing the pressure load against both flat surfaces of the saw material or saw blank to be hot pressed and a second power cylinder means (130b 2 ) for directing a pressure force against both longitudinal sides (Di, D 2 ) of the saw material or saw blank to be hot pressed. 30. Equipment according to patent application 29, characterised in that the equipment includes pressure tool (1 laj ', 1 la 2 '): selectively for forming the tongue joint (Ji) or groove (J 2 ) to the end side (D 3 , D 4 ) of the saw material or saw blank (200) or for pressingly thermal treating a tongue joint (Ji) or groove (J 2 ) or a preliminary groove located on the short end side (D 3 , D ) of the saw material or saw blank (200), and a third power cylinder means (130b 3 ) for directing a pressure force to the end side (D 3 , D ) of the saw material or saw blank (200). 31. Equipment according to any of claims 28-30, characterised in, that the pressure tools (l lai, Ha 2 ) of the equipment for the longitudinal sides (Di, D 2 ) of the saw material or saw blank (200) are formed to provide the grooves (J 2 , Ui, U 2 ) with the shape of deepened groove (U) to both longitudinal sides (Dj, D 2 ) and/or to pressingly thermal treat the grooves (J 2 , Ui, U 2 ) with the shape of deepened groove (U) at both longitudinal sides (Di, D 2 ). 32. Equipment according to any of claims 28-31, characterised in, that the pressure tools (l lai, H 2 ) of the equipment for the longitudinal sides (Di, D ) of the saw material or saw blank (200) are formed to provide into one longitudinal side (Di) the extension edge (Ji) that belongs to the groove and into the other longitudinal side (D 2 ) the groove (J 2 ) that belongs to the groove and tongue joint means. 33. Equipment according to any of claims 28-31, characterised in, that pressure tools (l lai, Ha 2 ) of the equipment for the longitudinal sides (Dj, D 2 ) of the saw material or saw blank (200) are formed to provide into one longitudinal side (Di) two extension edges (Ji) and the groove (Ui, U 2 ) with the shape of deepened groove (U) that belong to the double groove and tongue joint means and into the other longitudinal side (D 2 ) two groves (J 2 ) and the groove (Ui, U 2 ) with the shape of deepened groove (U) that belong to the double groove and tongue joint means. 34. Floor cover constructed of wood product according to any of preceding claims 1-11 and/or by method according to any of the preceding claims 12-27 and/or of any of the wood products produced by means of equipment according to any of the preceding claims 28-33, characterised in, that there is integrated into the floor surface cover a floor-heating including at least one floor-heating element, which locates in a canal formed by grooves (Ui, U 2 , U') locating in longitudinal sides (Di, D 2 ) or bottom side of the wood products (100, 100', 100"), and cross section profile of which corresponds essentially to the cross section profile of the groove, whereby also a heat transfer surface between the heating element and opposite side surface of the groove is as large as possible. 35. Floor cover according to claim 33, characterised in, that the floor-heating element integrated into the floor cover is an electric resistance or a flow pipe for heat transfer medium, such as air or liquid. 36. Floor surface cover, such as floor board, parquet or another floor cover, charac- terised in that the floor cover consists of floor elements, longitudinal sides (Di, D 2 ) of which are provided with a groove or grooves (U, Ui, U 2 ), by means of which there is formed a canal, whereby a floor-heating element is installable inside the floor cover.

Inventors: KUKKONEN MATTI, KUKKONEN, MATTI
Applicants: ILVOLANKOSKI OY, KUKKONEN MATTI, KUKKONEN, MATTI
Application year: 2001
Main classification: B27M1
IPC codes: B27M1, B27M3, E04F15