KR102476537B1 - Wood drying method for manufacturing high-quality wood - Google Patents

Abstract

A wood drying method for producing high-quality wood is disclosed. Wood drying method for manufacturing high-quality wood according to the present invention comprises the steps of measuring the weight of wood and calculating the moisture content; and accommodating the wood in the chamber and then drying the wood using a microwave irradiator that irradiates the wood with microwaves based on the type and moisture content of the wood, wherein drying the wood is performed for a first predetermined time. irradiating wood with microwaves intermittently at intervals of 1 hour; Measuring the temperature of wood after a first predetermined time has elapsed; Determining whether the temperature of the wood has reached a set temperature; and intermittently irradiating the wood with microwaves at a second time interval according to a set condition for a second predetermined time when the temperature of the wood reaches the set temperature.

Description

Wood drying method for manufacturing high quality wood {WOOD DRYING METHOD FOR MANUFACTURING HIGH-QUALITY WOOD}

The present invention relates to a wood drying method for producing high quality wood.

In general, raw wood or primary processed wood contains a large amount of moisture, so when used for construction or furniture, the wood is dried and used.

Wood drying methods include natural drying and artificial drying.

The natural drying method is a method of reducing the moisture content of wood by exposing the wood to the atmosphere, and this natural drying method takes too long time to dry the wood and has a problem in that it is difficult to obtain the moisture content required for a specific purpose.

In order to solve the problems of the natural drying method, an artificial drying method was developed, and the artificial drying method is a method of controlling the moisture content of wood in an artificially controlled environment.

The artificial drying method has the advantage of rapidly drying the wood compared to the natural drying method, and the artificial drying method includes methods such as hot air drying, vacuum drying, and dehumidifying drying.

In particular, in the case of hot air drying, wood can be dried more quickly than natural drying, but wood deformation and splitting occur frequently. When drying wood with hot air, heat transfer is not uniform, so the surface of the wood dries quickly, but moisture remains inside the wood, so the surface of the wood tends to shrink while the inside of the wood does not shrink, resulting in high drying stress. When the level of this drying stress exceeds the inherent mechanical strength of wood, deformation and splitting of wood occur.

Accordingly, the present applicant proposed a wood drying method using microwaves in order to prevent deformation and excessive splitting of wood in Korean Patent Registration No. 10-2014484.

However, even when drying wood using microwaves, fine splitting may occur in wood. Therefore, in order to improve the quality of dried wood, it is possible to improve practicality by minimizing the splitting of wood and producing wood having high strength. Research is needed.

Republic of Korea Patent Registration No. 10-2014484 (2019.08.30. Notice)

Therefore, the technical problem to be solved by the present invention is to provide a wood drying method for manufacturing high-quality wood that can minimize splitting of dried wood and improve the strength of wood.

According to one aspect of the present invention, measuring the weight of wood and calculating the moisture content; and accommodating the wood in the chamber and then drying the wood using a microwave irradiator that irradiates the wood with microwaves based on the type and moisture content of the wood, wherein the drying of the wood is performed for a first predetermined time. intermittently irradiating the wood with microwaves at a first time interval; measuring the temperature of wood after the first predetermined time has elapsed; Determining whether the temperature of the wood has reached a set temperature; and intermittently irradiating the wood with microwaves at a second time interval according to the set condition for a second predetermined time when the temperature of the wood reaches the set temperature. can be provided.

When the temperature of the wood does not reach the set temperature, the microwave may be intermittently irradiated to the wood at the first time interval for the first predetermined time.

In the step of drying the wood, the wood is irradiated with microwaves while simultaneously compressing the wood with a compression unit, the compression unit being in close contact with the wood accommodated in the chamber, and compressing the wood; and at least one cylinder member coupled to the compression unit to elevate the compression unit in a height direction and to adjust compression force for compressing wood.

The step of drying the wood may include measuring the weight of the wood and calculating the moisture content after the second predetermined time has elapsed; and determining whether the moisture content of the wood reaches a set value after the second predetermined time has elapsed, and when the moisture content of the wood reaches the set value after the second predetermined time has elapsed, the wood is naturally dried. Further steps may be included.

The step of drying the wood further includes irradiating the wood with microwaves and rotating the wood using a support unit supporting the wood when the moisture content of the wood does not reach the set value after the lapse of the second predetermined time. When the wood is rotated, microwaves may be intermittently irradiated to the wood at the first time interval for the first predetermined time.

The support unit includes a pair of moving parts disposed to be horizontally movable inside the chamber and facing each other; And doedoe installed on each of the pair of moving parts, it may include a rotation unit for fixing both ends of the wood in the longitudinal direction and rotating the wood.

The rotation part is rotatably installed on the moving part, and one end is fixed to the wood; And doedoe installed in the moving unit, it may include a rotary motor coupled to the other end of the fixed shaft to rotate the fixed shaft.

In an embodiment of the present invention, microwaves are intermittently irradiated to wood at a first time interval for a first predetermined time according to set conditions in which different drying conditions are converted into data according to the type and moisture content of wood, so that the temperature of the wood reaches the set temperature. In one case, by intermittently irradiating the wood with microwaves at a second time interval for a second predetermined time to dry the wood, generation of heat and carbonization at a specific location of the wood during the drying process of the wood can be prevented.

In addition, the embodiment of the present invention can minimize the splitting of wood after drying by compressing wood during the drying process of wood, shorten the drying time of wood, improve productivity, and also make the structure of wood dense. High-strength compression wood can be obtained.

In addition, the embodiment of the present invention may rotate the wood during the drying process of the wood so that the entire wood is dried evenly.

1 is a side view showing a wood drying apparatus according to the present invention.
2 is a plan view showing a wood drying apparatus according to the present invention.
3 and 4 are perspective views showing a compression unit according to the present invention.
5 is a flowchart showing a wood drying method according to the present invention.
6 to 8 are operational state diagrams of the wood drying apparatus according to the present invention.

In order to fully understand the present invention and the advantages in operation of the present invention and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings. Like reference numerals in each figure indicate like elements.

1 is a side view showing a wood drying apparatus according to the present invention, Figure 2 is a plan view showing a wood drying apparatus according to the present invention, Figures 3 and 4 are perspective views showing a pressing unit according to the present invention.

1 to 4, the wood drying apparatus according to the present invention includes a chamber 110 in which wood T is accommodated, a plurality of microwave irradiators 130 installed spaced apart from each other in the chamber 110, and a chamber ( A temperature sensor (not shown) installed in the 110), a support unit 150 supporting the wood T, and a compression unit 170 continuously compressing the wood T while irradiating the wood T with microwaves And, it includes a control unit (not shown) for controlling the drying operation of the wood (T).

The chamber 110 according to this embodiment serves to provide a receiving space (S) for drying the wood (T).

Referring to FIG. 1 , wood T enters and exits the chamber 110 through a door (not shown) provided in the chamber 110 . In addition, water vapor generated during the drying process of the wood T is discharged to the outside through a plurality of outlets (not shown) provided in the upper part of the chamber 110 .

In addition, a guide rail R is installed on the inner bottom surface of the chamber 110, and a support unit 150, which will be described later, enters and exits the chamber 110 along the guide rail R.

A temperature sensor (not shown) for measuring the temperature of the wood T may be installed on the sidewall of the chamber 110 . A non-contact type infrared temperature sensor may be used as the temperature sensor. The infrared temperature sensor measures the temperature of the wood T through a through hole (not shown) formed on the side wall of the chamber 110 . At this time, while the microwave irradiator 130 is operating, the through-hole is blocked to protect the infrared temperature sensor, and while the microwave irradiator 130 is stopped, the infrared temperature sensor measures the temperature of the wood T through the through-hole. And the temperature of the wood (T) measured by the infrared temperature sensor is transmitted to the control unit.

The microwave irradiator 130 according to the present embodiment serves to dry the wood T by irradiating microwaves into the chamber 110 .

As shown in FIG. 2 , a plurality of microwave irradiators 130 are installed spaced apart from each other on opposite side walls of the chamber 110 .

The microwave irradiators 130 installed to be spaced apart from each other on one side wall of the chamber 110 and the microwave irradiators 130 installed to be spaced apart from each other on the other side wall opposite to one side wall of the chamber 110 are installed in opposite directions but do not overlap each other. can be installed alternately. This is to ensure that the microwaves uniformly affect the entire area of the wood T to be dried.

Also, the microwave irradiators 130 may irradiate the wood T with microwaves in a zigzag direction. That is, the microwave irradiators 130 installed on both side walls of the chamber 110 are arranged offset from each other around the timber T disposed in the longitudinal direction inside the chamber 110, and the microwave irradiated from the microwave irradiator 130 The wood (T) can be evenly dried by irradiating the wood (T) at an angle rather than perpendicularly to the wood (T).

The temperature of the wood T is heated to 90 to 160° C. by the microwave irradiators 130 . As described above, the temperature of the wood T may be measured using an infrared temperature sensor. The control unit may control the intensity of the microwave or the irradiation time of the microwave according to the temperature of the wood T.

In addition, the control unit may control the intensity of the microwaves or the irradiation time of the microwaves according to setting conditions in which different drying conditions are converted into data according to the type of wood T and the initial moisture content.

Here, the setting conditions are the type of wood (T), the size, weight and density of wood (T), the initial moisture content of wood (T), the intensity of microwaves, the wavelength of microwaves, the wood after the drying process derived by the irradiation time of microwaves, etc. It is expressed in a relational formula or table prepared by converting at least one result value of the moisture content of (T) and the temperature of the wood (T) into data. The user can determine the intensity, wavelength, irradiation time, compression force for compressing the wood, etc. of the microwave considering the type, size, weight, density, moisture content, etc. of the wood (T) to be dried with reference to these setting conditions.

The support unit 150 according to the present embodiment supports the wood T during the drying process and serves to rotate the wood T to dry the wood T evenly.

The support unit 150 is provided to be horizontally movable inside the chamber 110 and installed on a pair of movable parts 151a disposed facing each other and a pair of movable parts 151a, respectively, and the wood (T) It includes a rotating part (153a) for fixing both ends in the longitudinal direction of and rotating the wood (T).

The pair of movable parts 151a may be moved closer to each other or spaced apart from each other along the guide rail R installed on the bottom surface of the chamber 110 according to the size of the wood T. On the other hand, during the drying process of irradiating the wood (T) with microwaves, the pair of movable parts (151a) are continuously moved from side to side to disperse the heated parts of the wood (T), thereby excessively heating a specific part of the wood (T). can prevent it from happening.

And the rotating part (153a) is installed on each of the pair of moving parts (151a) fixedly supports both ends of the longitudinal direction of the wood (T) and rotates the wood (T).

Specifically, the rotation unit 153a is rotatably installed on the moving unit 151a and has one end fixed to the wood T, and a fixed shaft 154a installed on the moving unit 151a and the other end of the fixed shaft 154a. It is coupled to and includes a rotation motor (not shown) for rotating the fixed shaft (154a).

The fixed support and rotation of the timber (T) by the support unit 150 as described above is to move the pair of movable parts (151a) adjacent to both ends in the longitudinal direction of the timber (T) according to the size of the timber (T). Then, the fixing shafts 154a are fixedly installed at both ends of the timber T in the longitudinal direction to fix and support the timber T. In addition, the fixed shaft 154a and the timber T may be rotated using a rotary motor in a state in which the timber T is fixed to the fixed shaft 154a. At this time, the control unit is electrically connected to the rotation motor to control the rotation time and rotation angle of the wood T.

And in the present embodiment, the microwave irradiators 130 installed spaced apart from each other on one side wall of the chamber 110 and the microwave irradiators 130 installed spaced apart from each other on the other side wall opposite to one side wall of the chamber 110 face each other. However, since they are installed alternately without overlapping with each other, while the wood T is rotated, the wood T is evenly exposed to the microwave, so that the entire wood T can be dried evenly.

On the other hand, even when the wood (T) is dried using microwaves, since fine cracks occur in the dried wood (T), in order to solve this, in drying the wood (T) to be dried using microwaves, the dried wood (T ) In order to improve the quality of the wood (T) by minimizing the occurrence of splitting, the wood (T) is compressed during the drying process of the wood (T). In addition, when the wood (T) is pressed during the drying process of the wood (T), the drying time can be shortened by easily discharging moisture or water vapor in the wood (T), and also by making the structure of the wood (T) dense The strength of the wood T may be improved. To this end, in this embodiment, a compression unit 170 installed in the chamber 110 to compress the wood T is provided.

The compression unit 170 according to the present embodiment is disposed on the upper and lower portions of the wood (T) accommodated in the chamber 110, respectively, and while irradiating the wood (T) with microwaves, the wood (T) accommodated in the chamber 110 T) plays a role in continuously compressing.

In this embodiment, the wood T is irradiated with microwaves to soften the wood, such as cellulose, hemicellulose, and lignin, and at the same time to compress the wood T, so that the wood T can be easily compressed.

In addition, the compression unit 170 may adjust the compression force for compressing the wood (T) according to the above-described setting conditions. That is, the compression unit 170 may adjust the compression force for compressing the wood T in consideration of the moisture content of the wood T after the drying process derived by the set conditions. For example, since the moisture content of the wood T decreases as the drying process progresses, the compression force for compressing the wood T may be gradually increased as the drying process proceeds to further lower the moisture content of the wood T.

1, 3 and 4, the compression unit 170 according to the present embodiment includes a compression unit 171 for compressing the wood T accommodated in the chamber 110, and a compression unit 171 ) It includes at least one cylinder member 177 that is coupled to the compression unit 171 to lift and lower the compression portion 171 in the height direction to compress and release the compression and release the compression and adjust the compression force for compressing the wood T.

At least one cylinder member 177 according to the present embodiment is provided on the upper and lower portions of the chamber 110, and is coupled to the compression unit 171 to lift the compression unit 171 in the height direction to cut the wood T. It plays a role in compressing and releasing compression.

The cylinder member 177 may be configured in various forms such as a hydraulic cylinder or an air cylinder, and a compression unit 171 is detachably coupled to an end of a rod of the cylinder member 177. Depending on the setting conditions, the pressing force for compressing the wood (T) can be controlled to vary, and the rod of the cylinder member 177 is extended or contracted to move the compression unit 171 coupled to the rod of the cylinder member 177 in the height direction. can be elevated to

And the compression part 171 according to this embodiment is coupled to the rod of the cylinder member 177, and as the rod of the cylinder member 177 is extended and contracted, it descends and rises in the height direction from the top of the wood T, Depending on the pressure applied by the cylinder member 177, the compression force for compressing the wood T is adjusted.

In addition, since the compression unit 171 continuously compresses the wood (T) supported by the support unit 150 according to the set conditions during the drying process, the occurrence of splitting of the dried wood (T) is minimized to The quality can be improved, the drying time of the wood (T) can be shortened by allowing moisture in the wood (T) to be easily discharged, and the strength of the wood (T) can be improved by making the structure of the wood (T) dense. can

3 and 4, the compression unit 171 is in contact with the wood (T) and the compression plate 172 for compressing the wood (T), one side is coupled to the rod of the cylinder member 177 and the other side is A first compression force transmission member 175 coupled to the compression plate 172 and distributing the compression force applied from the cylinder member 177 in the longitudinal direction or width direction of the compression plate 172 and transmitting the compression force to the compression plate 172; The first compression force is detachably coupled to the compression force transmission member 175 and disposed to cross the first compression force transmission member 175 to apply the compression force applied from the cylinder member 177 in the longitudinal direction or width direction of the compression plate 172 It includes at least one second compression force transmission member 176 that distributes and transmits the compression plate 172 .

The compression plate 172 directly contacts the wood (T) and compresses the wood (T). The compression plate 172 passes microwaves and may be made of a material having high strength and heat resistance of 100° C. or higher. For example, the compression plate 172 may be made of a metal material such as steel or a material such as Teflon, polyethylene (PE), polypropylene (PP), or polycarbonate (PC).

Compression plate 172 is formed in a shape corresponding to the shape of the wood (T). For example, when the wood T has a rectangular cross section, the compression plate 172 may have a flat plate shape in contact with one surface of the wood T. On the other hand, in the present embodiment, the wood (T) to be dried is shown as having a rectangular cross section, but is not limited thereto, and the wood (T) may have a cross section of various shapes such as a circular cross section.

Also, when the wood T has a rectangular cross section, the pressing plate 172 may be formed as a single flat plate as shown in FIG. 3 .

In addition, as shown in FIG. 4 to increase the size of the compression plate 172 according to the size of the wood T, the compression plate 172 may be configured by combining a plurality of unit compression plates 172a with each other. . That is, when the pressing plate 172 is composed of a plurality of unit pressing plates 172a, as shown in FIG. 4, the plurality of unit pressing plates 172a may be arranged side by side in a horizontal direction and coupled to each other to be folded. there is. For example, side surfaces of the unit compression plates 172a may be mutually coupled by coupling members 174 (eg, hinges) so that the plurality of unit compression plates 172a can be mutually folded.

3 shows a coupled state of the compression plate 172 composed of a single flat plate, the first compression force transmission member 175, and the second compression force transmission member 176. The cylinder member 177 is connected to the compression plate 172 via the first compression force transmitting member 175 . The first compression force transmission member 175 may be formed long in a bar shape. And the first compression force transmitting member 175 is long coupled to the upper surface of the compression plate 172 in the longitudinal direction (X direction) of the compression plate 172. On the other hand, although not shown, the first compression force transmitting member 175 may be long coupled to the upper surface of the compression plate 172 in the width direction (Y direction) of the compression plate 172 .

In addition, the rod of the cylinder member 177 is coupled to the upper surface of the first compression force transmitting member 175 . Therefore, when the rod of the cylinder member 177 is contracted and extended, the first compression force transmission member 175 also rises and falls in the height direction, and the compression plate 172 coupled to the first compression force transmission member 175 also increases in height. lifted in the direction

The first compression force transmitting member 175 is coupled to the cylinder member 177 and lifted, and when the compression plate 172 compresses the wood T, the compression force applied from the cylinder member 177 is transferred to the compression plate 172. Distributed in the longitudinal direction (X direction) or the width direction (Y direction) and transmitted to the compression plate 172.

In addition, when the wood (T) is compressed with the compression plate 172, the compression force of the cylinder member 177 is applied in a direction crossing the direction in which the compression force of the cylinder member 177 is distributed by the first compression force transmission member 175. A second compression force transmission member 176 is installed to distribute and transmit the pressure to the compression plate 172 .

The second compression force transmission member 176 is detachably coupled to the first compression force transmission member 175 and disposed to cross the first compression force transmission member 175 . The second compression force transmission member 176 distributes the compression force applied by the cylinder member 177 in the longitudinal direction (X direction) or width direction (Y direction) of the compression plate 172 and transmits it to the compression plate 172 .

And in order to detachably couple the second compression force transmission member 176 to the first compression force transmission member 175, the first compression force transmission member 175 is a coupler 175a to which the second compression force transmission member 176 is coupled. ) (for example, a through hole, etc.). In addition, the compression plate 172 includes at least one fixture 173 (eg, a fixing ring) to which an end of the second compression force transmitting member 176 is fixed to the upper surface rim.

Meanwhile, FIG. 4 shows a coupled state of the compression plate 172 composed of a plurality of unit compression plates 172a, the first compression force transmission member 175, and the second compression force transmission member 176. In the case of compressing the wood (T) with the compression plate 172, the plurality of unit compression plates 172a are prevented from being folded upward and at the same time, the compression force of the cylinder member 177 by the first compression force transmission member 175 A second compression force transmission member 176 is installed to distribute the pressure of the cylinder member 177 in a direction crossing the distribution direction and transmit the pressure to the compression plate 172 .

In addition, the second compression force transmission member 176 is detachably coupled to the first compression force transmission member 175 and disposed to cross the first compression force transmission member 175 . The second compression force transmission member 176 distributes the compression force applied from the cylinder member 177 in the longitudinal direction (X direction) or width direction (Y direction) of the plurality of unit compression plates 172a to the compression plate 172 convey

And in order to detachably couple the second compression force transmission member 176 to the first compression force transmission member 175, the first compression force transmission member 175 is a coupler 175a to which the second compression force transmission member 176 is coupled. ) is provided with at least one. In addition, at least one fixture 173 into which the end of the second compression force transmission member 176 is inserted and fixed is provided on the upper surface of the unit compression plate 172a disposed at the outermost part of the plurality of unit compression plates 172a.

The control unit according to the present embodiment is electrically connected to the chamber 110, the temperature sensor, the microwave irradiator 130, the support unit 150, and the compression unit 170 so that the wood T can be dried in an optimal state. control so that

A wood drying method for producing high-quality wood using the wood drying apparatus according to the present invention configured as described above will be described.

5 is a flow chart showing a wood drying method according to the present invention, and FIGS. 6 to 8 are operational state diagrams of a wood drying apparatus according to the present invention.

5 to 8, in the wood drying method according to the present embodiment, after preparing a wood (T) to be dried, the size and initial weight (Wi) of the wood (T) are measured, and then the wood (T) is measured. The initial moisture content (Mi) of the wood (T) is calculated (S100).

The initial moisture content (Mi) of the wood (T) can be calculated based on Equation 1 below.

<Equation 1>

In Equation 1, the dry weight (kg) can be calculated through the basic density (db, kg/m ³ ) × dry volume (m ³ ) of the wood (T) to be dried. Here, the basic density and dry weight of the wood T to be dried have unique values depending on the type of wood.

And, referring to FIG. 1, after accommodating the wood (T) in the chamber 110 and moving the pair of moving parts (151a) adjacent to both ends in the longitudinal direction of the wood (T), the fixing shaft (154a) They are fixed to both ends in the longitudinal direction of the timber (T).

At this time, as shown in FIG. 6, the rods of the cylinder members 177 disposed on the upper and lower portions of the timber T are contracted, and the compression plates 172 are spaced apart from the upper and lower surfaces of the timber T. do. And by rotating the rotary motor to align the upper and lower surfaces of the wood (T) side by side with the compression plate 172 disposed on the top and bottom of the wood (T).

And after accommodating the wood (T) inside the chamber 110, microwaves are irradiated to the wood (T) according to the setting conditions based on the type of wood (T) and the initial moisture content (Mi), and the wood is pressed by the compression unit (170). The upper and lower surfaces of (T) are compressed simultaneously to dry the wood (T) (S200). As described above, the setting conditions are determined by the type of wood (T), the size, weight and density of wood (T), the initial moisture content (Mi) of wood (T), the intensity of microwaves, the wavelength of microwaves, and the irradiation time of microwaves. After the derived drying process, at least one result value of the moisture content (M) of the wood (T) and the temperature of the wood (T) is converted into data and expressed as a relational expression or table. When the type of wood (T) and the initial moisture content (Mi) are determined, the intensity and wavelength of the microwave, irradiation time, compression force, and the like are determined according to the setting conditions.

Specifically, in the process of drying the wood T, first, as shown in FIG. 7 , while irradiating the wood T with microwaves, the wood T is compressed by the pressing unit 170 at the same time.

Specifically, during the first predetermined time period t1, microwaves are intermittently irradiated to the wood T at a first time interval Δt1 according to setting conditions based on the type of wood T and the initial moisture content Mi, etc. ( S210).

When the wood (T) is continuously irradiated with microwaves, a specific location of the wood (T) is intensively heated, and in particular, a core portion of the wood (T) may be carbonized or ignited. Therefore, in this embodiment, microwaves are intermittently irradiated to the wood (T). Since the core of the wood (T) is first heated by the microwave, when the microwave irradiation is stopped after irradiating the wood (T) with microwaves for a predetermined time, the heat of the heated core of the wood (T) is transferred to the wood (T) by thermal conduction. Since it is transmitted to the inside and outside, carbonization of the core of the wood T can be prevented.

During the first predetermined time period t1, the wood T is intermittently irradiated with microwaves at a first time interval Δt1, for example, the microwaves are irradiated for 30 seconds, and then the microwave irradiation is stopped for 15 seconds (first The operation with the time interval (Δt1) is repeated for one hour (first predetermined time (t1)). Here, the first time interval Δt1 and the first predetermined time t1 are determined by setting conditions. The first time interval (Δt1) is to prevent the wood (T) from being carbonized while heating the wood (T) with the microwave while maintaining the intensity of the microwave constant according to the set conditions, and the first predetermined time (t1) ) is the time it takes for the temperature of the wood (T) to be heated to the set temperature (Ts) of 90 to 160 ° C according to the type of wood (T) and the initial moisture content (Mi) of the wood (T). The set temperature Ts is an optimal temperature condition for evaporating moisture in the wood T and softening the wood quality of the wood T, and may vary depending on the type of wood.

After the first predetermined time period t1 has elapsed, the temperature of the wood T is measured (S220).

And it is determined whether the temperature of the wood (T) has reached the set temperature (Ts) (S230). This is to determine whether the temperature of the wood (T) has reached the set temperature (Ts), which is an optimal temperature condition for evaporating moisture in the wood (T).

Then, when the temperature of the wood T reaches the set temperature Ts, the wood T is intermittently irradiated with microwaves at a second time interval Δt2 according to the set conditions for a second predetermined time period t2. (S240).

For example, after irradiating microwaves for 15 seconds, an operation having a pause time of 30 seconds (second time interval Δt2) to stop microwave irradiation is repeated for 2 to 3 hours (second predetermined time period t2). Here, the second time interval Δt2 and the second predetermined time t2 are determined by set conditions. The second time interval (Δt2) is to maintain the temperature of the wood (T) at the set temperature (Ts) without overheating the core of the wood (T), and the second time interval (Δt2) is the first time period (Δt1). ) can be greater than And, the second predetermined time t2 is set to a time sufficient to evaporate moisture in the wood T.

On the other hand, when the temperature of the wood (T) does not reach the set temperature (Ts), the first time interval is set according to the set conditions based on the type of wood (T) and the initial moisture content (Mi) for the first predetermined time (t1). The process of intermittently irradiating the wood (T) with microwaves is repeated with (Δt1).

In addition, microwaves are intermittently irradiated to the wood T at a second time interval Δt2 according to the set conditions for a second predetermined time t2, and then the weight (W) of the wood T is measured and the moisture content (M) is determined. It is calculated (S250).

The pressing operation and microwave irradiation of the wood T are stopped, the weight W of the wood T is measured, and the moisture content M of the wood T is calculated based on Equation 1.

Then, after the lapse of the second predetermined time (t2), it is determined whether the moisture content (M) of the wood (T) has reached the set value (Ms) (S260). Here, the set value (Ms) is different depending on the type of wood (T) and may be 20 (% db) or less.

And when the moisture content (M) of the wood (T) reaches the set value (Ms) after the lapse of the second predetermined time (t2), the wood (T) is naturally dried (S400), and the drying process for the wood (T) is performed. quit

On the other hand, when the moisture content (M) of the wood (T) does not reach the set value (Ms) after the second predetermined time (t2) has elapsed, as shown in FIG. By contracting the rod of the cylinder member 177, the pressing plates 172 are spaced apart from the upper and lower surfaces of the wood T, and the wood T is fixed to the fixed shaft 154a using a rotary motor. The fixed shaft 154a is rotated to rotate the wood T at a predetermined angle (S270). While rotating the wood (T), microwaves are irradiated to the wood (T).

And when the wood is rotated, as shown in 6, the upper and lower surfaces of the wood T are compressed again with the pressing plates 172 spaced apart from the top and bottom surfaces of the wood T, and at the same time the first predetermined time (t1) ), the step of intermittently irradiating the wood T with microwaves is repeated at a first time interval Δt1 according to the set conditions.

As such, the present invention is not limited to the described embodiments, and it is obvious to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, it should be said that such modifications or variations fall within the scope of the claims of the present invention.

100: wood drying device 110: chamber
130: microwave irradiator 150: support unit
170: compression unit

Claims (7)

Measuring the weight of wood and calculating the moisture content; and
After accommodating the wood in the chamber, drying the wood using a microwave irradiator that irradiates the wood with microwaves based on the type and moisture content of the wood,
Drying the wood is
intermittently irradiating the wood with microwaves at a first time interval for a first predetermined time and simultaneously compressing the wood with a pressing unit;
measuring the temperature of wood after the first predetermined time has elapsed;
Determining whether the temperature of the wood has reached a set temperature; and
When the temperature of the wood reaches the set temperature, intermittently irradiating the wood with microwaves at a second time interval according to a set condition for a second predetermined time and simultaneously compressing the wood with the pressing unit,
The compression unit,
A compression plate accommodated inside the chamber, contacting the wood and compressing the wood, and a first compression force transmission member coupled to the compression plate and distributing the compression force in the longitudinal direction or the width direction of the compression plate and transferring the compression plate to the compression plate. and at least one second compression force detachably coupled to the first compression force transmission member and disposed to cross the first compression force transmission member to distribute the compression force in the longitudinal direction or the width direction of the compression plate and transmit it to the compression plate. A compression unit having a transmission member; and
At least one cylinder member coupled to the first compression force transmission member to lift and lower the compression plate in a height direction to compress and release wood, and to control a compression force for compressing wood;
The first compression force transmission member includes at least one coupler to which the second compression force transmission member is coupled, and the compression plate has at least one fixture to which an end of the second compression force transmission member is fixed to a rim. Wood drying method for wood manufacturing.
According to claim 1,
When the temperature of the wood does not reach the set temperature, the wood is intermittently irradiated with microwaves at the first time interval for the first predetermined time and wood is dried for high-quality wood manufacturing by simultaneously compressing the wood with the pressing unit. method.
delete According to claim 1,
Drying the wood is
measuring the weight of wood and calculating the moisture content after the lapse of the second predetermined time; and
Further comprising the step of determining whether the moisture content of the wood has reached a set value after the second predetermined time has elapsed,
Wood drying method for manufacturing high-quality wood, further comprising the step of naturally drying the wood when the moisture content of the wood reaches the set value after the lapse of the second predetermined time.
According to claim 4,
Drying the wood is
Further comprising irradiating the wood with microwaves and rotating the wood using a support unit supporting the wood when the moisture content of the wood does not reach the set value after the second predetermined time has elapsed,
When the wood is rotated, microwaves are intermittently irradiated to the wood at the first time interval for the first predetermined time and at the same time the wood is compressed with the pressing unit.
According to claim 5,
The support unit is
a pair of movable units provided to be horizontally movable inside the chamber and disposed to face each other; and
A wood drying method for manufacturing high-quality wood, comprising a rotating part installed on each of the pair of movable parts, fixing both ends in the longitudinal direction of the wood and rotating the wood.
According to claim 6,
the rotating part,
Doedoe rotatably installed on the moving part, one end of the fixed shaft fixed to the wood; and
Wood drying method for manufacturing high-quality wood comprising a rotation motor installed in the moving part and coupled to the other end of the fixed shaft to rotate the fixed shaft.

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