Wood shaping methods

Abstract

Improve the method of forming wood objects. The present invention relates to a method for forming an object made of wood, comprising the steps of: obtaining a workpiece by cutting the wood in a cross-grain direction crossing the fibres of the wood; positioning the workpiece using a die; and pressing the workpiece using a forming press applied to the free face of the workpiece while applying pressure in the grain direction parallel to the fibres of the wood, the pressing pressure being 1.5×10 6 N / m 2 the pressing step being cold pressing and the pressing step being dry pressing, the die having a positioning side against the workpiece during pressing, the positioning side making a first angle with the wood fibres of the workpiece placed in the die not exceeding 5°, and the forming press having a punching side against the workpiece during pressing, the second, punching side making a second angle with the wood fibres of the workpiece placed in the die not exceeding 5°. The invention also relates to a wooden object obtained using this method.

Description

[Technical Field]

[0001] The present invention relates to a method for shaping wood, and more particularly to a method for making wood products using pressure. [Background technology]

[0002] In general, woodworking presses are a well-known technique for creating woodworking products. This technique often involves applying significant force to the surface of a workpiece made of wood placed in a die, thereby compressing the wood to impart a predetermined shape and simultaneously increasing the strength of the object as a result of increased density. This technique also has the advantage of enabling the creation of recessed shapes that are impossible with milling, such as polygonal shapes with sharply defined corners.

[0003] In most cases, compression is applied in the transverse grain direction, perpendicular to the wood fibers. This is because the pressure required to compress wood in the transverse grain direction is much lower than the pressure required to compress the same wood in the longitudinal grain direction, parallel to the fibers. In other words, the energy required to bring the fibers closer together through compression is less than the energy required to compress the fibers in the longitudinal direction.

[0004] Compressing wood in the direction of the grain, parallel to the fibers, has also been proposed, but this method is rarely used because the pressure required to compress wood fibers along the grain can be extremely high, making it impossible for ordinary presses or large objects to handle.

[0005] Patent Document 1 describes a wooden object, such as a housing for an electronic device, obtained by compressing a previously machined (e.g., milled) workpiece. In this document, the bottom of the die (or mold) on which the workpiece is placed is greatly curved to avoid demolding problems and problems with the sharpness of the finished product's contour. The workpiece requires pre-processing for cavity formation, such as milling. The depth of the cavity is increased only by the pressing process. Only the bottom of the cavity is subjected to compression. In contrast, the top surface of the workpiece is not deformed by the action of the forming press. The aesthetic appearance of the outer and inner edges of the object is determined primarily by milling. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] European Patent Application Publication No. 1706248 [Overview of the project] [Problems that the invention aims to solve]

[0007] One of the objectives of the present invention is to propose a method for forming woody materials that is free from the limitations of methods known from the prior art.

[0008] Another objective of the present invention is to propose an ecological and economical method for forming woody materials.

[0009] Another object of the present invention is to propose a method for shaping woody objects that can quickly obtain particularly clean sides and fronts, as well as sharp corners.

[0010] Another object of the present invention is to propose a method for forming wood-based molded bodies that can quickly obtain moisture resistance and impact resistance. [Means for solving the problem]

[0011] In the present invention, these objects are achieved in particular by a method for shaping an object made of wood, which comprises the following plurality of steps. These steps are - a step of obtaining a workpiece by cutting in a cross-grain direction intersecting the fibers of the wood, - a step of positioning the workpiece using a die, - a step of pressing the workpiece while applying pressure along the grain direction parallel to the wood fibers, using a shaping press brought to the workpiece so as to be applied to the free surface of the workpiece and in this method, the pressure during pressing exceeds 1.5×10 2 , , , , 6 ,

[0014] , ,

[0013] N / m 2 , the pressing step is a cold pressing, the pressing step is a dry pressing are characterized in that, the die has a positioning side portion that is applied to the workpiece during pressing and forms a first angle not exceeding 5° with the wood fibers of the workpiece arranged in the die, the shaping press has a punching side portion that is applied to the workpiece during pressing , the above the punching side portion forms a second angle not exceeding 5° with the wood fibers of the workpiece arranged in the die characterize at least one of them.

[0012] The pressure during the pressing step preferably exceeds 2x10 6 N / m 2 and preferably exceeds 5x10 6 N / m 2 . The force used to press the fibers in the direction parallel to the grain is on the order of to 20 times that of the compression perpendicular to the grain.

[0013] The punching side portion slides along the grain of the workpiece during pressing.

[0014] The punched-out side may slide along the grain of the workpiece during pressing without contributing to compression in the longitudinal direction of the fibers, or, if the punched-out side is not parallel to the grain of the fibers, contributing to this compression only in a very limited manner.

[0015] In one embodiment, the entire punching side and the positioning side slide along the wood grain of the workpiece during pressing.

[0016] Compression along the grain of the wood provides advantages to the resulting object.

[0017] In particular, the surfaces, edges, and contours of the finished object are defined by the wood fibers, resulting in particularly sharp definitions. These fibers are compressed themselves, yet maintain their linearity.

[0018] When punching and positioning sides are parallel to the wood grain during pressing, the lateral surfaces of the object along these sides are defined by the lateral surfaces of the compressed continuous fibers, and the end faces (ends of the fibers) are not visible on these surfaces.

[0019] As a result, the roughness of the sides is very low, and the sides become especially smooth when they come out of the press.

[0020] On the one hand, the number of fiber ends that appear on the side of the object can be limited, even if the angle between at least one of the punched-out side and the positioning side, and on the other hand, the angle between the wood fibers and the punched-out side is less than 5°, thus enabling the acquisition of a clean (non-rough) smooth surface.

[0021] These sides and at least one of the front surfaces, defined by fibers compressed longitudinally along the grain, are particularly resistant to moisture and impact.

[0022] The workpiece does not require prior machining of recessed housings or voids.

[0023] One or more recessed portions of the component may be obtained by only pressing without prior machining.

[0024] Since high pressure is used, there is no need to wet or heat the wood to deform it.

[0025] 1.5x10 6 N / m 2 A pressure exceeding, preferably 2x10 6 N / m 2 A pressure exceeding, more preferably 5x10 6 N / m 2 makes it possible to obtain objects with sharply defined surfaces and edges, and even objects with polygonal cavities or contours.

[0026] 1.5x10 6 N / m 2 A pressure exceeding 0.5 kg / dm 3 has been demonstrated by tests to enable compression of at least 50% of the height (along the grain) of the workpiece for wood with a density of or less. As an example, for wood with an average density of 0.5 kg / dm 3 the height of the workpiece can, as a result, be compressed by up to 50% without damaging the finished product. For wood with a lower density, even greater compression can be applied without breakage. For example, for wood with a density of 0.4 kg / dm 3 the maximum height of the workpiece can be compressed by 60% without endangering the integrity of the workpiece.

[0027] The forming press and the die may be provided with guide side portions that slide relative to each other during the press. The guide side portion(s) advantageously hold the die in an exact fixed position during the press, ensuring controlled deformation and precision forming. Thereby, the workpiece is fixed during the press.

[0028] The guide side portion belonging to the die may guide the forming press during the press, thereby contributing to obtaining sharply defined sides on the compressed component.

[0029] The pressing process may be carried out using a forming press having a first side perpendicular to the grain of the wood and a second flat side, the two flat sides connected by a punched side.

[0030] The pressing process may include a step (process) for guiding the forming press, and the guide side of the die guides the forming press.

[0031] The guide side is advantageously parallel to the pressing direction.

[0032] The guide side is advantageously parallel to the grain direction of the wood fibers.

[0033] In this way, the wood is compressed longitudinally while being pressed laterally against the positioning sides of the die.

[0034] The maximum height of the workpiece in the direction of the wood grain can be reduced during pressing.

[0035] The height of the die's guide side can be greater than the maximum height of the workpiece before pressing.

[0036] At least one of the first surface, the second surface, and the bottom surface of the die may be structured.

[0037] The minimum determination interval for the structural relief may be very fine, i.e., between 10 μm and 50 μm. This allows for the formation of a very fine structure on the surface of the wood.

[0038] The punched-out side may be provided with a first chamfer that particularly smooths the transition between the inner side and the inner bottom of the manufactured object.

[0039] The first chamfered portion may have an angle of up to 35° with respect to the bottom surface of the die.

[0040] The positioning side of the die may, in particular, include a second chamfer that smooths the transition between the outer side and the outer bottom surface of the object being manufactured.

[0041] The second chamfered portion may have an angle of up to 55° with respect to the bottom surface of the die.

[0042] The forming press may have a stepped profile in the lateral or longitudinal direction. This is particularly useful for approximating curves that would otherwise be difficult to achieve.

[0043] The pitch of the steps in a stepped staircase can be very fine, typically between 0.01 mm and 0.2 mm.

[0044] This method may include a step after the step of pressing the workpiece in which the workpiece is removed so as to peel it off from at least one of the die and the forming press.

[0045] The material being processed is 0.75 kg / dm 3 Less than 0.5 kg / dm 3 It is acceptable if the pre-press density is less than a certain amount.

[0046] The wood from which the workpiece is cut may be chestnut, okoume, Japanese pine, linden (lime), alder, poplar, balsa, spruce, fir, maple, walnut, ash, or beech.

[0047] By introducing a machining process for the workpiece before the pressing process, the porosity and density of the workpiece can be increased.

[0048] The mechanical processing may involve multiple micro-perforations aligned with the grain of the wood fibers.

[0049] Microdrills may be manufactured by punching using a drill bit or, for example, a needle driven simultaneously in a direction parallel to the grain of the wood fibers.

[0050] One end of the forming press that contacts the workpiece may have a chamfered contour.

[0051] According to the present invention, these objectives can also be achieved by wooden objects obtained by the methods described herein.

[0052] Exemplary embodiments of the present invention are shown in the description accompanied by the accompanying drawings. [Brief explanation of the drawing]

[0053] [Figure 1] Figure 1 shows a possible method for cutting a workpiece from a block of wood. [Figure 2] Figure 2 shows the die into which the workpiece is placed. [Figure 3a] Figure 3a shows the pressing process in which a forming press is applied to the workpiece inside the die. [Figure 3b] Figure 3b shows the pressing process in which a shaping press compresses a portion of the workpiece. [Figure 4] Figure 4 shows a cross-section of a die containing a wood workpiece (the die's positioning surface is inclined). [Figure 5] Figure 5 shows a cross-section of the workpiece passing through the die that holds the workpiece and through the forming press (the positioning side of the die and the guide side of the press are inclined). [Figure 6] Figure 6 shows a cross-section through a forming press equipped with a punch having an inclined punching side. [Figure 7] Figure 7 shows a cross-section of a die with a specific housing holding a wooden workpiece. [Figure 8] Figure 8 shows a cross-section through a forming press with a specific contour having two punched-out sections. [Figure 9] Figure 9 shows a cross-section through the structured die at the bottom. [Figure 10a] Figure 10a shows a cross-section of the workpiece after passing it through a forming press, before various pressures are applied to the surface of the workpiece. [Figure 10b] Figure 10b shows a cross-section of the workpiece after it has been subjected to a forming press, with various pressures applied to its surface. [Figure 11a] Figure 11a shows a chamfered forming press. [Figure 11b] Figure 11b shows a chamfered forming press. [Figure 12] Figure 12 shows a die with a chamfered bottom surface. [Figure 13] Figure 13 shows two positions of the device used to remove the forming press after pressing. [Figure 14a] Figure 14a shows a forming press with a stepped section on one side. [Figure 14b] Figure 14b is a view from below of a forming press whose contour has a stepped section. [Figure 15a] Figure 15a shows a forming press equipped with multiple punches. [Figure 15b] Figure 15b shows a forming press equipped with multiple punches. [Modes for carrying out the invention]

[0054] The present invention relates to a method for shaping a wooden object by compressing a workpiece, wherein the compression is performed in a direction parallel to the wood grain.

[0055] Examples of wooden products that can be obtained using the method of the present invention include toys, cutlery handles, ornaments, tableware, boxes, watch cases, jewelry boxes, cosmetic containers or packaging, sundries, or clothing elements such as buttons and footwear, and others.

[0056] The method of the present invention is particularly suitable for containers of viscous products such as ointments, creams, or liquids. This is because densification by pressing reduces the porosity of the wood, resulting in sufficient impermeability to hold viscous or liquid products. As a result, the transport pathway is closed, reducing the risk of molecules moving from the wood to materials in contact with it, or vice versa. In addition, wood is a naturally inert material with antibacterial properties, has a pleasant feel, and often possesses a scent that is perceived as comforting.

[0057] Figure 1 shows a possible method for cutting a workpiece 11 from a piece of wood 10. The cutting is performed along the cutting line 12, perpendicular to the wood grain, to allow for compression parallel to the wood grain in the second stage. The terms "cross-grain" or "transverse" here should be understood as meaning a direction that is "not parallel" to the wood grain, i.e., a direction in which the angle between the cutting line 12 and the wood grain is not zero.

[0058] The workpiece 11 obtained by cutting is then positioned in or with the die 20. The die includes positioning sides 21 that are applied to the workpiece. As shown in Figure 2, the workpiece is positioned in the die such that one side of the workpiece, crossing the wood grain, is exposed, and the positioning sides and the bottom surface of the die surround the workpiece over the remaining surface. Positioning the workpiece may consist of simply placing the workpiece through an open portion of the die that guides the forming press, or in more complex embodiments, the workpiece may be introduced laterally into the die housing. Such embodiments are shown in Figure 7, where geometric constraints on the workpiece necessitate that the workpiece be positioned in the die 20 by sliding it, for example, perpendicular to the pressing direction. The workpiece may also be positioned by openings machined into the workpiece or by multiple die components that can grip each other.

[0059] Once the workpiece 11 is positioned relative to the die 20, it is pressed by the forming press 30. The direction of the press is parallel to the wood grain of the workpiece. In this way, the forming press is pressed against the exposed surface of the workpiece, and pressure is applied to the forming press to deform the workpiece until all or part of the volume of at least one of the forming press and the die is reproduced in the workpiece as a negative value.

[0060] One of the features of the present invention's method is that the pressing process involves dry pressing with a cold press. Hot pressing can reduce the pressing force required to deform the wood. However, the rise in the wood's temperature promotes drying, which in turn increases the tendency for deformation, particularly shrinkage, requiring correction or causing cracking. Such corrections can be avoided by steaming the wood before pressing or by using a die that can shrink to a specific dimension. However, such processes further complicate the method and increase its cost.

[0061] Dry pressing also means that the woodworking piece does not require pre-pressing immersion, and typically does not require immersion in a curing resin or steaming.

[0062] The forming press includes a punching side portion 303 that is applied to the workpiece during pressing.

[0063] Figure 3a shows the first step of this method, in which the workpiece 11 is brought against the positioning side 21 and positioned within the die 20, and the forming press 30 is moved toward the exposed surface of the workpiece. Figure 3b shows the second step, in which the central part of the forming press 30 compresses the workpiece 20, forming a depression on the side of the workpiece.

[0064] During the pressing process, the forming press 30 is brought into mechanical contact with the exposed surface of the workpiece 11. To minimize the lateral movement of the forming press as it moves toward the workpiece, the die may be provided with a first guide side 24 that guides the forming press. In a preferred embodiment, this first guide side may consist of a portion of a positioning side 21. In another embodiment not shown, the guide side 24 of the die may be a modular element firmly fixed to the die to increase the surface area that serves to guide the forming press. One function of this first guide side 24 is to ensure accurate guidance of the forming press relative to the die and the workpiece during pressing.

[0065] As shown in Figures 3a and 3b, the forming press may include a second guide side 32 that slides against at least one of the first guide side 24 and the positioning side of the die during the movement of the forming press 30. To optimize press guidance, the diameter of the forming press at the portion of the second guide side is made slightly smaller than the inner diameter of the die at the portion of the first guide side, leaving a clearance of 0.01 mm to 0.5 mm necessary to remove the object after pressing.

[0066] To optimally hold the workpiece 11 during pressing, the positioning side 21 of the die is ideally parallel to the wood grain. However, to facilitate demolding of the workpiece after pressing, at least one positioning side of the die may be slightly inclined by a first angle α with respect to the wood grain, forming a truncated cone whose widest diameter is located on the exposed side of the workpiece. Such an embodiment is shown in Figure 4. This first angle α may be at most 5° with respect to the pressing direction, i.e., the direction along the wood grain when the workpiece is placed inside the die.

[0067] In one embodiment, the die includes an inclined positioning side as described herein to facilitate demolding, and a guide side that is substantially perpendicular to the positioning side to ensure guidance of the press during pressing.

[0068] The clearance between the first positioning side portion 21 and the workpiece is preferably very small before pressing, allowing insertion of the workpiece into the die but ensuring secure fixation of the workpiece during pressing while avoiding lateral deformation. In one preferred embodiment, this clearance is preferably less than 0.5 mm.

[0069] The forming press 30 in Figure 5 includes a second guide side 32 that, like the positioning side 21, is inclined at a third angle β with respect to the compression direction to match the inclination of the positioning side. The third angle β may be at most 1° with respect to the pressing direction. Figure 5 shows an embodiment in which the guide side 32 of the forming press forms an angle β corresponding to the inclination of the positioning side 21.

[0070] A die or individual forming press may have one or more inclined positioning or guiding sides and at least one other positioning or guiding side parallel to the wood grain of the wood fibers. This allows for effective guidance of the forming press to the die throughout the entire movement of the forming press.

[0071] By inclining the second guide side 32 of the forming press to form an angle β with respect to the wood grain of the wood fibers, for example, demolding of the workpiece after the pressing process can be facilitated. However, this inclination prevents the vertical movement of the forming press relative to the workpiece as soon as the second guide side of the forming press comes into contact with the first guide side 24 of the die, thus preventing the forming press from guiding within the die.

[0072] In another embodiment, the die 20 is disassembled to facilitate demolding of the wooden object after pressing. Alternatively or additionally, the die may also have a punching die that similarly facilitates demolding of the object.

[0073] There are two distinct problems that may arise during demolding. Firstly, the forming press 30 and the workpiece may remain stuck to each other, and secondly, the die and the workpiece may similarly remain stuck to each other.

[0074] To separate the forming press from the workpiece after pressing, a demolding support may be positioned above the die, as shown in Figure 13. The demolding support may include a rod that is movable relative to the die and parallel to the press axis, capable of pressing the upper portion of the die so as to mechanically separate the die, which holds the pressed workpiece, from the forming press.

[0075] In another embodiment, the movable rod is replaced by a retaining ring that can press the workpiece as the forming press is withdrawn, so that the forming press is withdrawn from the workpiece.

[0076] Forming press 30 hit Side section 303 This forms a second angle γ with respect to the wood grain. This angle may be varied between 0° and 5° to allow for a wider variety of shapes to be pressed onto the workpiece and to facilitate demolding of the workpiece from the press after pressing. As a result, the contour of the punched side of the forming press will taper slightly, as shown in Figure 6. This second angle γ also allows for a higher quality finish on the internal surface of the wooden object.

[0077] Alternatively, a drawing mechanism may be used to remove or detach the object from the die after pressing. These drawing mechanisms consist, for example, of a die or a modular element of the forming press. Generally, the addition of a drawing mechanism is preferable when the punching side of the forming press is vertical, i.e., when angle γ is equal to 0°.

[0078] In one preferred embodiment shown in Figure 6, the forming press 30 comprises a first flat surface 301 and a second flat surface 302 perpendicular to the wood grain when the workpiece 11 is in a predetermined position within the die 20, and these surfaces are connected by a punching side 303 of the forming press. The first flat surface and the punching side together make a punch that determines at least one of the shape and volume for the compression of the workpiece. During the pressing process, the first flat surface 301 is the first part of the forming press that, after contacting the workpiece, penetrates the workpiece by the effect of pressure.

[0079] In another embodiment shown in Figure 8, the forming press 30 comprises a plurality of punches capable of forming a plurality of different marks (punching marks) on the workpiece 11. Each punch comprises a first flat surface 301 perpendicular to the wood grain when the workpiece is in a predetermined position within the die, a second flat surface 302, and a punching side 303 connecting the first flat surface and the second flat surface.

[0080] Here, the term "punch" is used to refer to the protruding portion of the forming press at the end closest to the workpiece during pressing. Figures 15a and 15b show a forming press with multiple punches, for example, three punches. The three punches may have different widths. The punches are thus separated laterally by the punching side 303 of the forming press or by the notches 305 of the forming press.

[0081] The minimum determination spacing of wood for pressing with a forming press equipped with multiple punches, i.e., the minimum distance between the nearest ends of two consecutive punches, should be between 0.1 mm and 10 mm, preferably 0.5 mm and 8 mm, typically between 1 mm and 5 mm. This resolution is related to many variables, such as the type of wood and the depth of the press. Figure 15a shows a forming press with a determination spacing of the order of 3 mm, meaning that the width of the notch 305 is approximately equal to 3 mm. Figure 15b shows an embodiment where the determination spacing is approximately 2 mm and the indentation is offset particularly from the center of the forming press.

[0082] The shape of the lower portion of the punching side 303 of the forming press 30, that is, the portion that first contacts the workpiece during pressing, is of particular importance with respect to the sharpness of the side and the sharpness of the transition between the bottom and side of the wood part obtained from the press.

[0083] In one embodiment, the punched-out side forms an acute angle with respect to the forming press portion, which is perpendicular to the wood grain of the wood fibers.

[0084] As shown in Figures 11a and 11b, the punched-out side portion 303 may have a chamfered portion 304 that provides a chamfer corresponding to the workpiece after pressing. Such a chamfered portion is typically used to smooth the transition between the side and the bottom of the part obtained after pressing the workpiece.

[0085] In terms of internal geometry, the transition between the vertical side and the bottom surface of the die 23 typically exhibits an acute angle with a chamfer of up to 35°, preferably up to 30°.

[0086] Alternatively or additionally, the punched-out sides 303 may be radially shaped so that the angle they make with the bottom surface of the die does not exceed 35°, preferably 30°.

[0087] In embodiments not shown, the guide side 303 may have a chamfered portion on its upper surface to form a chamfer on the outer shape of the workpiece during pressing. For such an outer shape chamfer, the chamfer angle is typically in the range of up to 50°.

[0088] As shown in Figure 12, the positioning side portion 21 of the die may have a chamfered portion 211 at the transition between the positioning side portion and the bottom surface of the die.

[0089] Such a chamfered portion 211 particularly facilitates the removal or peeling of the workpiece from the die after pressing. It also allows for a sharply defined transition between the outer side surface of the workpiece and the outer surface of the bottom of the workpiece. The chamfered portion 211 typically has an angle of up to 55°, preferably 45°, with respect to the bottom surface of the die.

[0090] To improve the way in which parts are formed from a workpiece by press working, the punching side portion 303 of the forming press 30 may have a relatively small stepped contour with a pitch equal to the size of the workpiece. Such a stepped contour makes it particularly possible to approximate curves that are complex to achieve in the pressing process without compromising visual representation. It is also possible to improve the clarity of certain transition areas between the side and bottom surfaces of the workpiece.

[0091] In the embodiment shown in Figure 14a, the contour of the transition between the pressing process and the lower part of the forming press is stepped, with a pitch, i.e., the depth of the step treads, between 0.01 mm and 0.2 mm. Thus, the step treads are perpendicular to the wood grain when the workpiece is in the die.

[0092] In another embodiment, the guide side has a stepped contour in which the tread surface is parallel to the wood grain of the workpiece. Figure 14b shows a stepped contour of a forming press, which is obtained by cutting in a die with a plane perpendicular to the wood grain of the workpiece. As described above herein, pressing curved portions, especially when the curvature is parallel to the wood grain, presents problems in terms of side sharpness, particularly when the angle of the curve is large. This problem can be overcome by approximating such curves with stepped portions in which the rectangular section is sharply defined during the pressing process.

[0093] The sharpness of the side definition may depend on the press speed. Generally, higher press speeds result in sharper, more defined sides. This speed is typically between 4 mm / s and 180 mm / s.

[0094] During the pressing process, the workpiece 11 may be compressed across its entire exposed surface or across one or more predetermined areas corresponding to the shape of the forming press. Therefore, the maximum height H of the workpiece in the direction of the wood grain may be reduced after pressing if the entire workpiece is compressed. In contrast, the maximum height H of the workpiece in the direction of the wood grain may remain the same after pressing if only one area of ​​the workpiece is compressed.

[0095] In Figure 3a, the workpiece has a maximum height H before pressing, but as shown in Figure 3b, the workpiece has a maximum height H' and a minimum height H'' after pressing. In all cases, the following relationship holds. H≧H'≧H” The following conditions are always met: When only a portion of the workpiece is pressed, H = H' > H'', and when the entire workpiece is pressed, H > H' ≥ H''.

[0096] The pressing process may be carried out by applying continuous pressure to the exposed surface of the workpiece with the forming press 30 so as to compress the entire desired height in a single operation. Alternatively or additionally, the pressing process may be carried out by applying a hammering action, which means continuous pressing of the exposed surface of the workpiece by the forming press.

[0097] Hammering allows for at least one of the following: reducing the pressing force required to press to the same height, and making the wood deeper and more densifying.

[0098] Alternatively or additionally, vibrations can be applied to the workpiece, die, or forming press, for example, longitudinal vibrations along the grain of the wood fibers at a frequency between 1 Hz and 1 MHz, to generate vibrations and facilitate compression of the workpiece by the forming press. These vibrations may play a role in making it easier for the forming press to penetrate the wood, making the wood fibers slide more easily against each other, and softening the wood by slightly heating it during pressing. Thus, as with hammering, applying these vibrations to the workpiece makes it possible to reduce the pressing force required to press to the same height and to densify the wood more deeply.

[0099] Structuring is equivalent to pressing a portion of the workpiece to form a relief, which is relatively small compared to the size of the workpiece. The relief obtained by structuring usually has a minimum determination interval on the order of the size of the water channels in the wood, i.e., between 10 μm and 50 μm.

[0100] The depth of the structured relief in the pressing direction is less than the distance the forming press travels within the workpiece. The depth of the structure in the pressing direction may be less than 2 mm.

[0101] In one embodiment, the forming press is structured to create a negative pattern on the workpiece during pressing. Alternatively or additionally, the bottom surface of the die is also structured to create a negative pattern on the outer surface of the workpiece that is in contact with the bottom surface of the die.

[0102] Structuring makes it possible to create logos, trademarks, text, patterns, and special textures (surface conditions) that have physical or aesthetic functions.

[0103] Alternatively or additionally, structuring elements may be placed between the forming press and the workpiece, or between the workpiece and the bottom surface of the die, so that the pattern of the structuring elements is negatively reproduced on the workpiece during pressing. Examples of structuring elements include cloth, leather pieces, paper pieces, and leaves. In one embodiment, the workpiece, particularly its sides, is formed in a first pressing step, and then a portion of the formed workpiece is structured in a second pressing step.

[0104] The portion of the forming press that comes into contact with the workpiece during pressing may be structured to generate a negative or positive image on the workpiece. At least one of the first flat surface and the second flat surface of the forming press may be structured.

[0105] Similarly, Figure 9 shows one embodiment in which the die, in this example the bottom surface 23 of the die opposite to the exposed surface of the workpiece, may also be structured to obtain a positive or negative pattern on the surface opposite to the exposed surface of the workpiece.

[0106] Such structuring of at least one of the forming press and die makes it possible to combine pressing the workpiece with negative or positive marking of patterns, with a view to forming wooden products.

[0107] The structured elements may include, for example, images, patterns, logos, letters, ribs, grooves, and the like on the surface of the forming press, so as to be negatively imprinted onto the workpiece.

[0108] Clearly, the type of wood selected for the workpiece has a significant impact on the pressing parameters and the diversity of manufacturable objects. Specifically, the higher the density of the wood, the greater the pressing force required to compress it to a given height. Therefore, the lower the density of the selected wood, the greater the compression and the larger the volume compressed.

[0109] Therefore, in one embodiment, the workpiece is 0.75 kg / dm 3 From wood with a density of less than 0.5 kg / dm 3 It is cut from wood with a density of less than 0.5 kg / dm³. Suitable tree species include, for example, poplar or lime / linden (approximately 0.5 kg / dm³). 3 ), spruce (approximately 0.45 kg / dm 3 ), Barça (approximately 0.14 kg / dm 3 Other tree species such as chestnut, maple, beech, fir, rice, Alola pine, or alder are also particularly suitable in the context of the present invention. The pressurization method of the present invention is 0.75 kg / dm 3 , or 0.85 kg / dm 3 This list of tree species is by no means limited, as it can be applied to wood of up to a certain density.

[0110] To increase the porosity of the wood and thereby facilitate the pressing process, a preliminary mechanical processing step may be performed on the workpiece. In one embodiment, a series of micro-perforations are made using a drill bit or needle punch to reduce the density of the workpiece before pressing. The holes thus made with micro-drills are filled during compression, so that the resulting object can be fluidly dense enough to hold viscous products (such as creams and pastes) or even liquid products.

[0111] The method of the present invention may also be used to manufacture objects that have no recesses on their upper surface, but only protrusions. In one embodiment, the method is used to manufacture wooden toy parts, such as stackable building blocks.

[0112] In one embodiment, the end of the forming press that initially holds the workpiece during pressing has at least one of a chamfer and / or a cut contour to facilitate entry into the wood. Such a contour also avoids the potential need for post-press filing work, as it provides a clean (non-rough) side (flank) to the wood being pressed.

[0113] In one embodiment shown in Figures 10a and 10b, various different pressures may be applied to multiple different sections of the workpiece during a single pressing process using a forming press. As shown in Figures 10a and 10b, a pressing force F2 is applied to a first lateral section of the workpiece, while another pressing force F1 is applied to the central portion of the workpiece. In this way, different compression densities and heights can be achieved in a single pressing process, while simultaneously ensuring optimal retention of the workpiece within the die during pressing.

[0114] The possibility of obtaining multiple different pressing forces from a single forming press can be achieved, for example, by attaching a spring above the lateral section of the forming press (i.e., above the section corresponding to pressing force F2). This allows the spring to absorb some of the pressing force in the lateral section of the workpiece, while the pressure in the central section is maximized, when the same pressing force is applied to the top of the forming press.

[0115] Furthermore, this method may also be applied when a second wooden workpiece is assembled to a first workpiece using press working. In embodiments not shown, the second workpiece is placed between the first workpiece and the forming press. The two workpieces are then assembled one to the other during the pressing process, under the influence of the pressure from the forming press. The assembly of the two workpieces is facilitated by pre-pressing two corresponding contours onto each of the surfaces of the workpieces that are intended to come into contact with each other.

[0116] While the grain direction of the wood fibers in the first workpiece is always parallel to the pressing direction, the grain direction of the wood fibers in the second workpiece may itself be parallel, perpendicular, or oblique to the pressing direction. This degree of freedom allows for interesting patterns to be created in the finished product, and by reducing the pressure required to compress the two workpieces, pressing becomes easier, or a particularly strong finished product can be obtained. Furthermore, combinations of wood with different densities and compressive strengths are also possible.

[0117] The assembly of the two components obtained using the described pressing method may be performed after pressing each component, for example, using a mortise and tenon. Components intended to be inserted into the other component may be dried before insertion. When moisture is recovered from the surrounding air, they tend to expand and strengthen the joint between the mortise and tenon.

[0118] Alternatively or additionally, the pressing method of the present invention may also be applied to workpieces made by gluing together two or more pieces of wood (wood chips) to enable pressing of larger workpieces. The joining may typically be done in the direction of the wood grain of the two pieces of wood. The resistance of the glued joint to pressing is essentially the same as that of an unglued workpiece. Furthermore, the adhesive lines become almost invisible after pressing. This application offers, for example, the following perspectives. [Perspective 1] - A process of obtaining a workpiece (11) by cutting wood (10) in the direction of the wood grain that intersects the wood fibers, - A step of positioning the workpiece using a die (20), - A pressing step in which a workpiece is pressed using a forming press (30) that is brought to strike the free surface of the workpiece while applying pressure along the grain direction parallel to the wood fibers. A method for forming an object made of wood, comprising: Pressing pressure is 1.5 × 10 6 N / m 2 To exceed, In the aforementioned pressing process, cold pressing is performed, In the aforementioned pressing process, dry pressing is performed, It is characterized by, The die (20) has a positioning side portion (21) that is applied to the workpiece during pressing, and the positioning side portion (21) is provided that makes a first angle (α) not exceeding 5° with the wood fibers of the workpiece positioned on the die, The forming press is provided with a second punching side (303) that is applied to the workpiece during pressing, which is a second punching side that creates a second angle (γ) not exceeding 5° with respect to the wood fibers of the workpiece located within the die. A method for shaping an object made of wood, characterized by at least one of the following. [Perspective 2] The method according to viewpoint 1, wherein the die (20) comprises an essentially vertical first guide side (24), and the forming press (30) comprises an essentially vertical second guide side (32), the second guide side being slidable relative to the first guide side during pressing. [Perspective 3] The method according to viewpoint 1 or 2, wherein the maximum height (H) of the workpiece (11) in the direction along the grain of the wood fibers decreases during pressing. [Perspective 4] The method according to viewpoint 2, wherein the height of the first guide side portion (24) of the die is greater than the maximum height (H) of the workpiece before pressing. [Perspective 5] The pressure during the pressing process is preferably 2 × 10 6 N / m 2 It is more than 5x10 6 N / m 2 The method described in any one of viewpoints 1 to 4, which is superior. [Perspective 6] The pressing process is carried out using a forming press (30) having a first flat surface (301) and a second flat surface (302) perpendicular to the grain of the wood, and the punching side (303) of the forming press connects the first flat surface and the second flat surface, according to any one of views 1 to 5. [perspective 7] The method according to any one of viewpoints 1 to 6, wherein the punched-out side portion (303) comprises a first chamfered portion (304). [Perspective 8] The method according to viewpoint 7, wherein the first chamfered portion (304) forms an angle of up to 35° with the bottom surface of the die. [Perspective 9] The method according to any one of viewpoints 1 to 8, wherein the positioning side portion (21) comprises a second chamfered portion (211). [Perspective 10] The method according to viewpoint 9, wherein the second chamfered portion (211) forms an angle of up to 55° with the bottom surface (23) of the die. [Perspective 11] The method according to any one of views 1 to 10, wherein the forming press (30) has a stepped staircase contour. [Perspective 12] The method according to viewpoint 11, wherein the pitch of the stairs is between 0.01 mm and 0.2 mm. [Perspective 13] The method according to any one of views 1 to 12, further comprising the step of removing the workpiece (11) after the step of pressing the workpiece, so as to remove the workpiece from at least one of the die (20) and the forming press (30). [Perspective 14] The method according to any one of views 1 to 13, wherein at least one of the forming press (30) and the bottom surface (23) of the die is formed by pressing to create a relief on the workpiece. [Perspective 15] The method according to viewpoint 14, wherein the minimum determination interval of the relief is 10 μm to 50 μm. [Perspective 16] The workpiece (11) has a weight of 0.75kg / dm 3 Less than 0.5 kg / dm 3 The method according to any one of viewpoints 1 to 15, characterized by having a pre-press density of less than 1. [Perspective 17] The method according to any one of viewpoints 1 to 16, wherein the wood is a tree species selected from chestnut, maple, beech, linden (lime), poplar, balsa, fir, okoume, Japanese pine, alder, walnut, ash, or spruce. [Perspective 18] The method according to any one of views 1 to 17, characterized by a step of mechanically processing the workpiece (11) before pressing to increase porosity and decrease density. [Perspective 19] The method according to viewpoint 18, wherein the mechanical processing step comprises a plurality of micro-drills or needle punches oriented in the direction of the wood grain of the wood fibers. [perspective 20] The method according to any one of views 1 to 19, wherein one end of the forming press (30) that contacts the workpiece has a chamfered contour. [Perspective 21] A wooden object obtained by any one of the methods described in viewpoints 1 to 20. [Explanation of symbols]

[0119] 10 wood 11 Workpiece 12 Cutting line 20 di 21 Positioning side 211 Second chamfered section 22 Housing 23 Die bottom 24 First guide side 30 Forming press 31 Punching section 32 Second guide side 301 First flat surface 302 Second flat surface 303 Punched surface 304 First chamfered section 305 notches 40 movable rods α 1st angle γ second angle β 3rd angle H Maximum height before press H' Maximum height after pressing H" Minimum height after pressing

Claims

1. - A process of obtaining a workpiece by cutting wood in the direction of the wood grain that intersects the wood fibers, - A step of positioning the workpiece using a die, A method for forming an object made of wood, comprising: a pressing step of pressing the workpiece using a forming press that is brought to strike the free surface of the workpiece while applying pressure along the grain direction parallel to the wood fibers, Pressing pressure is 1.5 x 10 ６ N / m ２ Exceeding, In the aforementioned pressing process, cold pressing is performed. In the aforementioned pressing process, dry pressing is performed. The forming press is equipped with a punching side that is applied to the workpiece during pressing, and the punching side creates a second angle not exceeding 5° with respect to the wood fibers of the workpiece located within the die. The contact surface between the forming press and the workpiece comprises a first flat surface perpendicular to the wood fibers and a second flat surface, and the punching side of the forming press connects the first flat surface and the second flat surface, so that during the pressing process, the first flat surface is the initial part of the forming press that contacts the workpiece and then penetrates it due to the effect of pressure. The die is provided with a positioning side portion that forms a first angle not exceeding 5° with respect to the wood fibers of the workpiece, which is applied to the workpiece during pressing and positioned within the die. A method for shaping objects made of wood.

2. The method according to claim 1, wherein the die has a first guide side that is essentially vertical, and the forming press has a second guide side that is essentially vertical, and the second guide side is slidable relative to the first guide side when pressing.

3. The method according to claim 1, wherein the maximum height of the workpiece in the direction along the grain of the wood fibers decreases during pressing.

4. The pressure during the aforementioned pressing process is 2 × 10 ６ N / m ２ The method according to claim 1, which is greater than or equal to the present.

5. The method according to claim 1, wherein the punched-out side portion is provided with a first chamfered portion.

6. The method according to claim 5, wherein the positioning side portion includes a second chamfered portion.

7. The method according to claim 6, wherein the second chamfered portion forms an angle of up to 55° with the bottom surface of the die.

8. The method according to claim 1, wherein the forming press has a stepped staircase contour.

9. The method according to claim 1, wherein at least one of the forming press and the bottom surface of the die is formed by pressing to create a relief on the workpiece.

10. The method according to claim 9, wherein the minimum determination interval of the relief is 10 μm to 50 μm.

11. The workpiece has a weight of 0.75 kg / dm ３ The method according to claim 1, having a pre-press density of less than 1.

12. The method according to claim 1, further comprising the step of mechanically processing the workpiece before pressing to increase its porosity and decrease its density.

13. The method according to claim 12, wherein the mechanical processing step comprises a plurality of micro-drills or needle punches oriented in the direction of the wood grain of the wood fibers.

14. A wooden object obtained by the method described in claim 1.

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