Progressive striking type high-frequency compaction assembly line and compaction method thereof

Abstract

The invention relates to a progressive striking type high-frequency compaction assembly line. The progressive striking type high-frequency compaction assembly line comprises operation equipment and a bearing component. The operation equipment comprises a preheating part, a high-frequency hot-pressing part and a water-cooling cold-pressing wood striking part; the high-frequency hot-pressing part comprises a plurality of high-frequency hot-pressing machines, a moving roller way of each high-frequency hot-pressing machine extends from an internal hot-pressing station to inlets and outlets in the two sides to be exposed, and the adjacent exposed moving roller ways are in butt joint; the water-cooling cold-pressing wood striking part comprises a plurality of water-cooling cold-pressing machines, a movable roller way of each water-cooling cold-pressing machine extends and is exposed towards inlets and outlets in the two sides from an internal pressing station, and the adjacent exposed movable roller ways are in butt joint; the bearing component is a tray which is arranged below the wood board and used for bearing the wood board. According to the production line, the high-frequency hot-pressing part, the water-cooling cold-pressing wood striking part and the bearing component are used, on the premise that the thickness of a wood board is allowed to rebound, the technical problems that in the prior art, due to the fact that an upper pressing plate and a lower pressing plate are needed for clamping and pressure maintaining, operation is complex, and process step adjustment is limited in the production line circulation process are solved, and the rebound problem is solved.

Description

[0001] Claims 1 to 7 of this application claim the domestic priority of the Chinese patent application with patent number 2024223456747, patent name "A progressive wake-up high-frequency compaction production line", and patent application date September 25, 2024. The basis is that the technical solutions of claims 1 to 7 of this application are clearly recorded in claims 1 to 10 of 2024223456747 (2024.9.25) and paragraph [0005-0063] of the specification. Technical Field

[0002] The invention relates to the technical field of wood board compaction, and in particular to a progressive wood-awakening type high-frequency compaction production line and a compaction method thereof. Background Art

[0003] Existing high-frequency technology has been widely used in wood board compaction. The softening of wood boards through high-frequency compaction is ideal, with short time and low energy consumption. However, since high-frequency pressurization technology requires high-pressure compression of the wood board in an ultra-short time, it is easy to cause serious rebound of the wood board once the pressure is removed. The high-frequency compacted wood combination production line with patent application number 201910181348.8 and application date 2019.03.11, the operating equipment of this production line adopts the close connection between the auxiliary high-frequency softening part, the main high-frequency stamping part, and the cooling part, and the "sandwich flow structure" of the upper and lower pressure plates clamping the wood board, so that the wood always maintains high pressure during the heating and cooling stages, thereby avoiding serious rebound of the wood due to pressure release. On the other hand, the moisture content of the compacted wood is reduced by clamping the upper and lower pressure plates of the porous plate structure to solve the rebound problem. The device for evenly discharging compressed water vapor on the surface of compacted wood with patent application number 202010100409.6 and application date 2020.02.18 also discloses a "sandwich flow structure" that uses upper and lower pressure plates to clamp the wooden board to maintain pressure (thickness), and increases the clamping of the porous plate to reduce the moisture content of the compacted wood, thereby solving the rebound problem.

[0004] In addition, the technical solutions of patent application number 202010100409.6 (application date 2020.2.18), patent application number 201811573895.2 (application date 2018.12.21), and patent application number 201910181346.9 (application date 2019.03.11) all use a "sandwich-type circulation structure" to maintain pressure transmission on the wooden board during processing to solve the problem of wooden board rebound. Although the above technical solutions have solved the problem of wood rebound to a certain extent, these devices use a "sandwich-type circulation structure" to maintain pressure on the wooden board during operation, which is cumbersome to perform pressurized heating and other processes during process circulation. For example, during high-frequency heating, the electrodes in the upper and lower pressing plates need to be connected to power on respectively, and cooling media need to be connected to the upper and lower pressing plates for cooling in the cooling step. When grabbing the template, the upper pressing plate needs to be grabbed first, resulting in cumbersome loading and unloading steps; affecting production efficiency and not conducive to achieving industrialized efficient production.

[0005] Based on the above technical problems, the applicant is committed to developing simpler auxiliary equipment and process technology on the basis of solving the problem of wood board rebound and maintaining the excellent physical properties of wood boards. The present invention proposes to simplify the existing load-bearing components, simplify the equipment and process flow by reducing the pressure plate, and expand the practicality of the equipment. Under the premise of simplifying the load-bearing components, how to maintain the mechanical properties of the wood board compression and avoid rebound through equipment and equipment technology is particularly critical. Summary of the invention

[0006] The purpose of the present invention is to solve the above-mentioned problems existing in the prior art. The present invention provides a simplified load-bearing component and a progressive high-frequency compaction production line with progressive compression technology.

[0007] The present invention is achieved through the following technical solutions:

[0008] A progressive wake-up wood type high-frequency compaction production line, the operating equipment includes a preheating part, a high-frequency hot pressing part and a water-cooled cold pressing wake-up wood part connected in sequence;

[0009] The high-frequency hot pressing part includes a plurality of high-frequency hot pressing machines, the second movable roller of each high-frequency hot pressing machine extends from the internal hot pressing station toward the inlet and outlet on both sides and is exposed, and the exposed second movable rollers of adjacent high-frequency hot pressing machines are butted;

[0010] The water-cooled cold-pressing wake-up wood part includes a plurality of water-cooled cold presses, and the third movable roller of each water-cooled cold press extends from the internal pressing station toward the inlet and outlet on both sides and is exposed, and the exposed third movable rollers of adjacent water-cooled cold presses are butt-jointed;

[0011] The bearing member comprises a pallet and a wooden board carried by the pallet. When the bearing member is supported and moved by a movable roller, the thickness direction of the wooden board is not constrained by the operating device.

[0012] Preferably, the preheating section comprises a plurality of preheating machines, and the first movable roller of each preheating machine extends from the internal preheating station toward the inlet and outlet on both sides and is exposed, and the exposed first movable rollers of adjacent preheating machines are butt-jointed.

[0013] Preferably, the operating equipment further comprises a loading section, a saturated water-cooled pressing section, a first conveying section, a second conveying section, an air-cooled roller section, a curing roller section and a discharging section;

[0014] The loading section, preheating section, high-frequency hot pressing section, water-cooled cold pressing section and saturated water-cooled pressing section are arranged in sequence on a first straight line in a forward direction; the air-cooled roller section, curing roller section and unloading section are arranged in sequence on a second straight line in a reverse direction, one side of the first conveying section is arranged on the downstream side of the saturated water-cooled pressing section, and the other side is arranged on the upstream side of the air-cooled roller section; one side of the second conveying section is arranged on the downstream side of the unloading section, and the other side is arranged on the upstream side of the loading section.

[0015] Preferably, the loading part comprises a wood board loading platform, a movable roller platform and a wood board picking mechanism;

[0016] One side of the wood board loading platform is docked with the mobile roller platform. The wood board loading platform is a translation roller, which is used to transport the wood boards to the side of the mobile roller platform. The wood board picking mechanism is arranged on the top of the mobile roller platform, and extends from the upstream side of the mobile roller platform to the upper side of the docking side of the wood board loading platform. The wood board picking mechanism adopts a suction cylinder and an air nozzle.

[0017] The unloading section includes a unloading moving roller platform and a unloading picking mechanism; the unloading picking mechanism is arranged on the top of the unloading moving roller platform, and extends on the upstream side of the moving roller platform to above the moving roller near the downstream side of the health roller section; the downstream end of the health roller section is connected to the second conveying section; the unloading picking mechanism adopts a suction cylinder and an air nozzle.

[0018] Preferably, the first conveying section is longitudinally arranged at the downstream side of the saturated water-cooled pressing section of the multiple lines, and the other end side of the saturated water-cooled pressing section is butted against the upstream roller of the air-cooled roller section, and a mechanical pusher is arranged at the end to push the wooden board to the air-cooled roller section; the first conveying section is a longitudinal moving platform, which is used to longitudinally move the water-cooled wooden board to one end of the air-cooled roller section;

[0019] The second conveying section is longitudinally arranged and one side thereof is respectively connected to the downstream end of the curing roller section and the side of the feeding section deviating from the preheating section; a mechanical pusher is provided at the connection with the side of the feeding section to push the tray onto the movable roller platform of the feeding section.

[0020] Preferably, a plurality of parallel first straight lines can be arranged between the loading section and the first conveying section, and the preheating section, the high-frequency hot pressing section, the water-cooled cold pressing section and the saturated water-cooled pressing section are arranged in sequence on each of the first straight lines.

[0021] Preferably, the surface of the pallet facing the wooden board is provided with a shallow groove whose shape matches the shape of the wooden board, and the surface of the pallet facing the wooden board is provided with a water diversion groove in the horizontal and / or vertical direction, and the water diversion hole that runs through the entire pallet is provided at the position of the water diversion groove.

[0022] The second aspect of the present invention discloses a compaction method using the above-mentioned progressive wake-up wood type high-frequency compaction production line, the method at least comprising the following steps:

[0023] High-frequency hot pressing treatment: The preheated load-bearing components are sequentially put into several hot presses for multiple hot pressings. The compression rate of the wood board increases step by step after hot pressing in each hot press according to the hot pressing sequence; the second time from the end of hot pressing in the previous hot press to the start of hot pressing in the next hot press is 20-30 seconds;

[0024] Water-cooled cold pressing wake-up wood treatment: the load-bearing components after hot pressing treatment enter several water-cooled cold presses in sequence for multiple water-cooled cold pressings. The temperature of the wood board decreases step by step after each water-cooled cold press according to the cold pressing sequence, and the compression rate of the wood board increases step by step after each water-cooled cold press according to the water-cooled cold pressing sequence; the interval from the end of cold pressing in the previous water-cooled cold press to the start of cold pressing in the next water-cooled cold press is 20-30 seconds.

[0025] Preferably, the high-frequency hot pressing step also includes a preheating treatment: the load-bearing component enters several preheating machines in sequence for multiple preheating, and the first time from the end of preheating of the previous preheating machine to the start of preheating of the next preheating machine is 5 to 20 seconds.

[0026] Compared with the prior art, the beneficial effects of the present invention include:

[0027] 1. The progressive high-frequency compaction line of the present invention is a production mode that adopts a fully automatic and efficient assembly line. Its unique progressive compression equipment - high-frequency hot pressing part and water-cooled cold pressing part, combined with simple load-bearing components, allows the thickness of the wood board to rebound. It changes the technical difficulties of the prior art that the upper and lower pressure plates need to clamp and maintain pressure, resulting in complex operation and limited adjustment of process steps during the production line flow process, greatly improves production efficiency, and truly realizes large-scale dark-light factory production with a high degree of automation.

[0028] 2. The production line of the present invention can be used for compacting logs and non-log materials, and has good versatility. In addition, the timing and method of heating and pressurizing of the high-frequency hot press equipment in this production line can be adjusted more flexibly, which greatly improves the practicability of the production line.

[0029] 3. The "progressive" technology of the progressive high-frequency compaction production line of the present invention is: the high-frequency hot press machine connected in series at intervals in the high-frequency hot press section is used to perform progressive hot pressing and compaction on the wood board, and the compression ratio of the wood board is gradually increased, thereby gradually increasing the temperature and compression rate of the wood, evaporating and discharging the water in the cell wall of the wood to the maximum extent, and reducing the rebound rate while increasing the density and hardness of the wood. After the high-frequency hot pressing, the wood board enters the high-pressure water cooler connected in series at intervals in the water-cooled cold press section for gradual pressurized water cooling. There is no need to maintain pressure between the high-pressure water coolers, making the processing method more flexible.

[0030] 4. The load-bearing components (i.e., the logs are placed in the hot press plate) and there is no upper press plate on the assembly line of the present invention. This structure facilitates loading and unloading, simplifies the structural complexity of the press plate, and omits the step of docking the upper metal press plate with the heating unit or refrigeration unit of the press, thereby simplifying the operating equipment and process steps. At the same time, in terms of the anti-rebound effect, the wood compacted by the progressive equipment of the present invention can achieve or even surpass the technical effect of the "sandwich circulation structure" and "traditional high-frequency conditions" in the prior art under the combination of the load-bearing components and the "progressive" technology of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the overall structure of the progressive wake-up wood type high-frequency compaction production line of the present invention.

[0032] Figure 2 It is a structural schematic diagram of the feeding part of the present invention;

[0033] Figure 3 It is a structural schematic diagram of the preheating part of the present invention;

[0034] Figure 4 It is a structural schematic diagram of the high-frequency hot pressing part of the present invention;

[0035] Figure 5 It is a schematic diagram of the structure of the water-cooled cold-pressed wood awakening part of the present invention;

[0036] Figure 6 It is a schematic structural diagram of the saturated water-cooled pressing part of the present invention;

[0037] Figure 7 It is a structural schematic diagram of the first conveying section of the present invention;

[0038] Figure 8 It is a structural schematic diagram of the discharge part of the present invention;

[0039] Fig. 9 It is a structural schematic diagram of the moisture content detection unit of the present invention;

[0040] Fig.10 It is a structural schematic diagram of the load-bearing component of the present invention. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0042] The progressive wake-up wood type high-frequency compaction production line of the present invention comprises an operating device and a bearing component.

[0043] The pipeline of the present invention is specially designed with a progressive compression device, which splits a high-frequency heating step that needs to be completed at one time into a plurality of high-frequency heating sub-steps that are gradually completed at a certain interval, splits a compression and densification step that needs to be completed at one time into a plurality of compression and densification sub-steps that are gradually completed at a certain interval, or splits a rapid cooling step that needs to be completed at one time into a plurality of rapid cooling steps that are gradually completed at a certain interval.

[0044] In a specific example, the operating equipment includes a preheating section, a high-frequency hot pressing section and a water-cooled cold pressing awakening section which are connected in sequence.

[0045] The high-frequency hot pressing part includes a plurality of high-frequency hot pressing machines, the second movable roller of each high-frequency hot pressing machine extends from the internal hot pressing station toward the inlet and outlet on both sides and is exposed, and the exposed second movable rollers of adjacent high-frequency hot pressing machines are butt-jointed.

[0046] The water-cooled cold pressing wake-up wood part includes several water-cooled cold pressing machines. The third movable roller of each water-cooled cold pressing machine extends from the internal pressing station toward the inlet and outlet on both sides and is exposed, and the exposed third movable rollers of adjacent water-cooled cold pressing machines are connected.

[0047] The bearing member includes a pallet and a wooden board carried by the pallet. When the bearing member is supported and moved by a movable roller, the thickness direction of the wooden board is not constrained by the operating device. The thickness direction of the wooden board is not constrained by other operating devices. Compared with the technical solution in the prior art that the wooden board needs to be clamped by upper and lower pressure plates to maintain the thickness of the wooden board in a compressed state, the wooden board does not need to be added with an upper pressure plate during the circulation process, and does not need to be pressed in the thickness direction all the time.

[0048] For another complete pipeline example, see Figure 1As shown, the operating equipment includes a loading section 1, a preheating section 2, a high-frequency hot pressing section 3, a water-cooled cold pressing section 4, a saturated water-cooled pressing section 5, a first conveying section 6, an air-cooled roller section 7, a curing roller section 8, a unloading section 9 and a second conveying section 10 which are sequentially installed. These operating equipments are sequentially arranged according to the wood board compacting steps of the present invention to form a complete production line.

[0049] Figure 1 In the example, on the basis of ensuring the automation of process operation, a more reasonable technical solution for setting up each operating equipment is as follows: the loading section 1, preheating section 2, high-frequency hot pressing section 3, water-cooled cold pressing section 4 and saturated water-cooled pressing section 5 are arranged in sequence on the first straight line in the forward direction, and the air-cooled roller section 7, curing roller section 8 and unloading section 9 are arranged in sequence on the second straight line on one side of the first straight line in the reverse direction, and the first straight line and the second straight line are two parallel lines of the same length. The first conveying section 6 serves as a guiding and steering device, one side of which is arranged on the downstream side of the saturated water-cooled pressing section 5, and the other side is arranged on the upstream side of the air-cooled roller section 7. The second conveying section 10 serves as another guiding and steering device, one side of which is arranged on the downstream side of the unloading section 9, and the other side is arranged on the upstream side of the loading section 1.

[0050] The load-bearing member is a pallet 100 placed under the wooden board for supporting the wooden board. Fig.10 As shown, structurally, the surface of the pallet 100 facing the wooden board is provided with a shallow groove 113, the shape of the shallow groove 113 is adapted to the shape of the wooden board, and can limit the wooden board, thereby preventing the wooden board from being misplaced to a certain extent. The surface of the shallow groove 113 is provided with a water diversion groove 110 in the horizontal and / or vertical direction, and the water diversion groove 110 is provided with a water diversion hole 114 that runs through the entire pallet 100. The pressure borne by the pallet 100 is set according to the working pressure of the laminating machine of the assembly line; in one example, the pressure borne by the pallet 100 is converted to: 2300T (tons) / 1.75 square meters, that is, kg / cm 2 The material can be converted based on this, such as stainless steel, alloy steel, and the present invention is not limited thereto.

[0051] The following is a detailed description of each operating device based on the flow direction of the pipeline.

[0052] Figure 2 As shown, the loading part 1 includes a wood board loading platform 12, a movable roller platform 11 and a wood board picking mechanism 13. One side of the wood board loading platform 12 is docked with the movable roller platform 11, and the wood board loading platform 12 is a translation roller for transporting wood boards to the side of the movable roller platform 11; the wood board picking mechanism 13 is arranged on the top of the movable roller platform 11, and extends from the upstream side of the movable roller platform 11 to above the docking side of the wood board loading platform 12.

[0053] It should be noted that the wooden board picking mechanism 13 can be a manipulator or a suction mechanism; preferably, a suction mechanism is used, and the suction mechanism includes a suction cylinder and a suction nozzle arranged at the output end of the suction cylinder. During operation, the suction cylinder controls the suction nozzle to suck and release the wooden board. The movable roller platform 10 is a translation roller, on which a pallet 100 is placed. The wooden board picking mechanism 13 grabs the wooden board and moves to the top of the pallet 100, and releases the wooden board on the pallet 100. The wooden board and the pallet 100 form a bearing member. One side of the movable roller platform 10 is docked with the preheating part 2, and a mechanical pusher is provided to push the bearing member to the preheating part 2 for the preheating process. In an improved example, in order to make the height of the wooden board adapt to the suction mechanism, a lifting platform is also provided under the loading station of the wooden board loading platform 10, which is used to raise the wooden board to be sucked to a suitable height for suction.

[0054] In order to improve the production efficiency of wood board compaction, the production line of the present invention adopts multiple lines to be arranged in parallel. Figure 1 As shown, the upstream side of the multiple lines is arranged in parallel from the side of the moving roller platform 10 of the feeding part 1. The preheating part 2, the high-frequency hot pressing part 3, the water-cooled cold pressing part 4 and the saturated water-cooled pressing part 5 are respectively arranged on each line.

[0055] The preheating section 2 on each line uses several preheating machines installed in series. The preheating machine can use an existing thermal oil preheating machine, a steam preheating machine or a high-frequency preheating machine, preferably a high-frequency preheating machine. In an improved scheme, the first movable roller of the preheating machine extends from the internal preheating station toward the inlet and outlet on both sides and is exposed, and the exposed first movable rollers of adjacent preheating machines are connected; the exposed first movable roller provides an intermittent pressure relief channel for the load-bearing components in the circulation process, so as to better realize the pressure relief of the load-bearing components between the current pressurizing device and the next pressurizing device.

[0056] Figure 3 A specific example is shown, the preheating section 2 includes two high-frequency preheating machines 201 and 202 connected in series, the two high-frequency preheating machines 201 and 202 apply a first pressure to the load-bearing member in turn, and preheat the wood board in the load-bearing member by high frequency, and then transport it to the high-frequency hot pressing section 3, and the load-bearing member is relieved of the first pressure within the first time after any high-frequency preheating machine 201 or 202 stops pressurizing. The first time is the time point when the current preheating equipment unit stops pressurizing (providing a compression ratio) as the time starting point, and the time point when the next equipment unit starts pressurizing (providing a compression ratio) as the time ending point. Preferably, the first time is 5-20 seconds.

[0057] The high-frequency hot pressing section 3 on each line adopts several high-frequency hot presses installed in series. The second movable roller of each high-frequency hot press extends from the internal hot pressing station toward the inlet and outlet on both sides and is exposed, and the exposed second movable rollers of adjacent high-frequency hot presses are butt-jointed. The heating temperature and working pressure parameters in each high-frequency hot press are determined according to the compression rate of the wooden board in the corresponding hot press, and the compression rate of the wooden board achieved by the several high-frequency hot presses from the upstream side to the downstream side increases step by step. The number of high-frequency hot presses is set according to the actual situation. In one example, Figure 4 As shown, preferably there are three, and the working temperature (heating temperature applied to the wooden board during operation) of the three high-frequency hot presses 301, 302, and 303 from the upstream side to the downstream side increases step by step, and the working pressure of the three high-frequency hot presses 301, 302, and 303 is the same. The three high-frequency hot presses 301, 302, and 303 apply a second pressure to the load-bearing member in turn, and heat the wooden board in the load-bearing member through high frequency, and then transport water-cooled cold pressing to wake up the wood part 4, and the load-bearing member releases the second pressure within the second time after any one of the high-frequency hot presses 301, 302, and 303 stops pressurizing. The first time is the time point when the current hot pressing equipment unit stops pressurizing (providing a compression ratio) as the time starting point, and the time point when the next equipment unit starts pressurizing (providing a compression ratio) is the time end point. Preferably, the second time is 10-30 seconds. The working temperature of the first high-frequency hot press 301 is 200°C, the working temperature of the second high-frequency hot press 302 is 250°C, and the working temperature of the third high-frequency hot press 303 is 300°C. The working pressure of the three high-frequency hot presses 301, 302, and 303 is 2300T (tons). By setting the working parameters of each high-frequency hot press, the progressive compression of the wood board is achieved.

[0058] The point of the progressive technology of the present invention is that each equipment unit in the prior art is closely connected, and in order to maintain the pressure, upper and lower positioning rollers are provided to maintain the pressure of the wooden board during movement. However, the equipment units of the present invention are provided with exposed docking rollers, and there is no need to provide positioning rollers at the intervals. After the previous equipment stops pressurizing, the wood fibers in the wooden board are allowed to rebound appropriately before the next pressurization. After repeated progressive operations of pressurization and pressure release in the high-frequency hot pressing section, the wood fiber structure of the wood fibers in the template is destroyed multiple times, thereby achieving the effect of weakening the recovery ability (i.e., rebound).

[0059] The main chemical components of wood are cellulose, hemicellulose and lignin (three major elements). If a large number of hydrogen bonds are formed in the cellulose, hemicellulose and lignin in the compacted wood, the compacted wood is less likely to rebound than other wood. In the progressive awakening wood high-frequency compaction production line of the present invention, since it includes multiple high-frequency heating sub-steps, multiple compression and densification sub-steps and / or multiple rapid cooling steps, the cellulose molecules, hemicellulose molecules and lignin molecules can be intertwined and stretched many times to form a larger number of hydrogen bonds with each other. In addition, the microstructure of the three major elements is more closely intertwined, which can better lock water molecules, so that the high-frequency compacted wood can better resist the destruction of hydrogen bonds by moisture when absorbing moisture, and achieve the technical effect of avoiding the problem of wood rebound without the need for an upper pressing plate.

[0060] On the other hand, the progressive compression technology of the present invention uses a high-frequency hot press machine with a high-frequency hot press section connected in series at intervals to perform progressive hot pressing and densification on the wood board. The compression ratio of the wood board is gradually increased, thereby gradually increasing the temperature and compression rate of the wood, evaporating and discharging the water in the wood cell wall to the maximum extent, and reducing the rebound rate while increasing the density and hardness of the wood. At the same time, because its load-bearing component omits the clamping restriction of the upper pressing plate, it provides conditions for flexible adjustment of the hot pressing process. For example, the high-frequency hot press machine can heat or not heat at the same time as high-frequency pressurization according to process requirements.

[0061] The high-frequency preheating machine of the preheating part 2 and the high-frequency hot pressing machine of the high-frequency hot pressing part 3 both have a pressing mechanism and a heating mechanism, and the pressing mechanism includes an upper template and a lower template arranged at the preheating station and the hot pressing station. The pressing mechanism and the heating mechanism of the hot pressing machine are conventional means in this field, so they are not described in detail with drawings. The specific structure can refer to the relevant technical solutions disclosed in the applicant's prior patent application No. 201811592197.7.

[0062] The water-cooled cold pressing wood awakening section 4 on each line uses several water-cooled cold presses. The third movable roller of each water-cooled cold press extends from the internal pressing station toward the inlet and outlet on both sides and is exposed. The exposed third movable rollers of adjacent water-cooled cold presses are butted, and the wooden board is also intermittently depressurized on the exposed third movable rollers that are butted. The heating temperature and working pressure parameters in each water-cooled cold press are determined according to the compression rate of the wooden board in the corresponding water-cooled cold press, and the compression rate of the wooden board achieved by the several water-cooled cold presses from the upstream side to the downstream side increases step by step. A low-temperature water cooling device for cooling the load-bearing components is installed at the high-frequency pressing station of each water-cooled cold press in this section. Figure 5The water-cooled cold pressing wake-up wood part 4 shown uses four water-cooled cold presses 401, 402, 403, 404, and the corresponding four water-cooled cold presses 401, 402, 403, 404 are respectively provided with low-temperature water cooling equipment, and the working pressure of the four water-cooled cold presses 401, 402, 403, 404 is the same, and is the same as the working pressure of the three high-frequency hot presses 301, 302, 303. In a preferred embodiment, the working pressure of the four water-cooled cold presses 401, 402, 403, 404 is 2300T (tons).

[0063] The saturated water-cooled pressing section 5 on each line uses a plurality of water-cooled pressing machines connected in series, and the water-cooled pressing machine can be a water-cooling machine conventionally used in this field. Figure 6 In an example shown, the saturated water-cooled pressing section 5 uses eight water-cooled pressing machines connected in series, adjacent water-cooled pressing machines are externally connected to the same pressing power supply, and every four water-cooled pressing machines are supplied with water by the same water cooler. In a preferred technical solution, the working pressure of the eight water-cooled pressing machines is 60T (tons).

[0064] Figure 6 In the example, the saturated water-cooled pressing part 5 has a pressing mechanism and a water cooler. The technical means of the pressing mechanism and the water cooler are conventional means in the art, so they are not described in detail with drawings.

[0065] Figure 7 As shown, the first conveying section 6 is longitudinally arranged at the downstream side of the saturated water-cooled pressing section 5 of multiple lines, and the other end side of the saturated water-cooled pressing section 5 is butted against the upstream roller of the air-cooled roller section 7, and a mechanical pusher is arranged at this end to push the wooden board to the air-cooled roller section 7. The first conveying section 6 is a longitudinal moving platform, which is used to longitudinally move the water-cooled wooden board to one end of the air-cooled roller section 7.

[0066] The air-cooled roller section 7 is composed of a plurality of air-cooling devices installed in series on an air-cooled moving roller, preferably ten.

[0067] Figure 8 As shown, the unloading section 9 includes a unloading moving roller platform 90 and a unloading picking mechanism; the unloading picking mechanism is arranged on the top of the unloading moving roller platform 90, and extends from the upstream side of the moving roller platform to the upper part of the moving roller near the downstream side of the health roller section 8. The unloading picking mechanism can be a manipulator or a suction mechanism, and the specific structure of the suction mechanism is as described above. The downstream end of the health roller section 8 is docked with the second conveying section 10, which is used to transport the unloaded pallet to the upstream side of the production line.

[0068] The second conveying section 10 is longitudinally arranged and one side thereof is respectively connected to the downstream end of the curing roller section 8 and the side of the loading section 1 deviating from the preheating section 2; a mechanical pusher is provided at the connection with the side of the loading section 1 to push the pallet to the movable roller platform of the loading section 1 to wait for the next cycle of wooden boards to be loaded.

[0069] The moving rollers in each part of the entire production line are transported by conveyor rollers.

[0070] Based on the above-mentioned assembly line equipment, each high-frequency preheating machine in the preheating section uses an exposed roller to make the first time interval of each preheating of the wooden board 5 to 10 seconds; each high-frequency hot press in the high-frequency hot pressing section makes the second time interval of each corresponding step of the wooden board in the process of 20-30 seconds; each water-cooled cold press in the water-cooled cold pressing wood-awakening section makes the second time interval of each corresponding step of the wooden board in the process of 20-30 seconds. The high-frequency hot pressing section includes three high-frequency hot presses, and the interval time of each hot pressing is equal. The temperature and the compression rate of the wooden board are progressive. The present invention does not specifically limit the amplitude of the gradual increase of the temperature and compression rate. The water-cooled cold pressing wood-awakening section includes four water-cooled cold presses, and the interval time of each cold pressing is equal. The compression rate of the wooden board is progressive. During the compaction process of the wooden board through the above-mentioned equipment, the compression ratio is increased step by step, and the temperature and compression rate of the wood are gradually increased. In the absence of the clamping of the upper pressing plate, the water in the wood cell wall can still be evaporated and discharged to the maximum extent to prevent rebound.

[0071] What circulates on the production line of the present invention is the load-bearing component (i.e., the original wood board is placed in the hot pressing tray) without an upper pressing plate. The advantage of such a design is, on the one hand, that it is convenient for loading and unloading, and on the other hand, it simplifies the structural complexity of the pressing plate, and there is no need to dock with the heating unit or the refrigeration unit of the press. Since there is no upper pressing plate, according to the conventional understanding of the prior art over the years, it is impossible to "maintain pressure" between the equipment units (the upper surface of the wood board cannot be directly passed through the "roller group"), which is not conducive to preventing rebound. Surprisingly, even in the absence of an upper pressing plate, through the progressive equipment compaction step of the present invention, in terms of the anti-rebound effect, the load-bearing component circulated in the present application, combined with the "progressive" compaction technology, can achieve or even be better than the technical effects of the "sandwich circulation structure" (the wood board clamped by the upper and lower pressing plates, the hot pressing plate is equivalent to the upper and lower pressing plates) and the "traditional high-frequency conditions" in the prior art.

[0072] In addition, the "hot pressing plate circulation structure" of the present invention is not limited by the upper pressing plate, so its production adaptability is wider and it can be applied to logs, such as poplar, birch and other woods, and can also be applied to non-logs.

[0073] The progressive compaction technology of the present invention strictly limits the compression rate of the wood board at each stage. Therefore, thickness measuring sensors for measuring the thickness of the wood board are installed at each machine unit position of the preheating part, high-frequency hot pressing part and water-cooled cold pressing part. In addition, the thickness measurement of the wood board before preheating is also particularly critical. In some improved examples, such as Fig. 9 As shown, a moisture content measuring section 80 is also provided upstream of the loading section of the production line, which is equipped with a moisture content measuring instrument for testing the moisture content of wood and a thickness measuring sensor for measuring the thickness of the template. The moisture content testing section 80 is a roller conveying section assembly and a measuring instrument provided on the roller conveying section assembly, and the roller conveying section assembly includes a testing section 82, a sorting section 83, an NG product output section 84, and an OK product output section 85.

[0074] The test section 82 is a longitudinal roller conveyor belt, which is arranged on the upstream side of the sorting section 83; the roller side of the test section 82 is installed with a microwave moisture meter antenna 86, a thickness measurement sensor 87 and a width measurement encoder 88 through a measuring bracket. The sorting section 83 is a transverse roller conveyor belt, and the NG product output section 84 and the OK product output section 85 are both longitudinal roller conveyors; the downstream side of the sorting section 83 is connected to the preheating section. The sorting section 83 is installed with a length measurement encoder 89 at the upstream end corresponding to the test section 82, which is used to measure the length of the wood passing through. The upstream end of the sorting section 83 is also provided with a lifting and conveying roller, which is used to clamp and convey the wood boards upstream of the sorting section 83 to the midstream. The NG product output section 84 is arranged on the midstream side of the sorting section 83, and the OK product output section 85 is arranged on the downstream side of the sorting section 83; the sorting section 83 is provided with lifting pushers at positions corresponding to the NG product output section 84 and the OK product output section 85, for pushing wooden boards of corresponding quality to the corresponding output sections.

[0075] The measurement process of the moisture content measuring unit 80 includes: 1. Measuring moisture content; 2. Measuring thickness with a thickness measuring sensor; 3. Measuring width with a width measuring encoder when passing through the position of the thickness measuring sensor; 4. Measuring length at the position of the lifting and clamping roller; 5. Calculating moisture content using the numerical values ​​of steps 2-4; 6. Classifying into NG products and OK products according to the value of moisture content.

[0076] It should be added that the "high-frequency compaction method" of the present invention is a wood strengthening treatment method that uses high-frequency voltage to perform high-frequency heating on the wood, performs overall compression and densification on the wood at a certain compression rate, and rapidly cools the wood under certain low temperature conditions. The compressed and enhanced wood is called high-frequency compacted wood. The "high-frequency compaction method" uses high-frequency medium heating equipment (applies high-frequency voltage) to heat the wood, uses a hydraulic press (applies compression rate) to perform overall compression and densification on the wood, and uses a cooling device (provides water or other temperature media) to rapidly cool the wood (there is also natural cooling using air as the temperature medium). In the assembly line equipment structure, the heating, compaction, and cooling steps can be performed simultaneously or separately according to the situation. When the high-frequency heating step and the compression and densification step are carried out simultaneously, the same high-frequency medium hot press can be used for the operation; when the high-frequency heating step and the compression and densification step are not carried out simultaneously, the compression and densification step can be carried out alone in a cold press; when the compression and densification step and the rapid cooling step are carried out simultaneously, the same water-cooled cold press can be used for the operation; when the compression and densification step and the rapid cooling step are not carried out simultaneously, the rapid cooling step can be carried out alone by a water-cooling device. Among them, the high-frequency heating step includes heating to soften, heating to increase temperature or heating to solidify, etc., depending on the high-frequency densification process of the specific wood. Softening is usually to increase the plasticity of the wood, and solidification and rapid cooling (quenching) are usually to enhance the physical properties of the high-frequency densified wood.

[0077] Based on the technical solution of realizing the progressive structure of the above-mentioned assembly line, the third aspect of the present invention discloses a progressive high-frequency compaction method, which at least comprises the following steps:

[0078] High-frequency hot pressing treatment: The preheated load-bearing components are sequentially put into several hot presses for multiple hot pressings. The compression rate of the wood board increases step by step after hot pressing in each hot press according to the hot pressing sequence; the second time from the end of hot pressing in the previous hot press to the start of hot pressing in the next hot press is 20-30 seconds;

[0079] Water-cooled cold pressing wake-up wood treatment: the load-bearing components after hot pressing treatment enter several water-cooled cold presses in sequence for multiple water-cooled cold pressings. The temperature of the wood board decreases step by step after each water-cooled cold press according to the cold pressing sequence, and the compression rate of the wood board increases step by step after each water-cooled cold press according to the water-cooled cold pressing sequence; the interval from the end of cold pressing in the previous water-cooled cold press to the start of cold pressing in the next water-cooled cold press is 20-30 seconds.

[0080] In an improved solution, the high-frequency hot pressing step also includes a preheating treatment: the load-bearing component enters several preheating machines in sequence for multiple preheating, and the first time from the end of preheating of the previous preheating machine to the start of preheating of the next preheating machine is 5 to 20 seconds.

[0081] In an improved solution, after the wood board is subjected to water-cooled cold pressing and wood awakening treatment, saturated water-cooled pressing, air-cooling and curing steps are performed.

[0082] It should be noted that the compression rate described in the present invention refers to the percentage of the original wood after compression treatment, that is, The compression ratio in this application refers to the raw wood cut before preheating. The compression ratio in this invention refers to the percentage of the raw wood after compression. The raw wood referred to in the compression ratio described in this application is based on the raw wood cut before preheating treatment.

[0083] According to the principle of the above method, the progressive wake-up wood type high-frequency compaction method is specifically described below through an embodiment.

[0084] Example 1

[0085] Cut logs into suitable sizes, the density of the logs is 0.5-0.6g / cm 3 , control the average moisture content to about 10%, place the wooden board in the shallow groove of the pallet to form a load-bearing component. The load-bearing component is placed in the progressive high-frequency compaction production line of the present invention to perform the following process steps:

[0086] 1) Preheating treatment: The load-bearing components enter the preheating equipment for preheating to a temperature of 100-130°C for 20-30 seconds, and the compression rate of the wood board is 15-25%.

[0087] 2) High-frequency hot pressing treatment: the preheated load-bearing components are sequentially put into three hot presses for hot pressing, and are respectively subjected to high-frequency heating to a temperature of 140-160°C and kept warm for 2-4 minutes, high-frequency heating to a temperature of 160-180°C and kept warm for 2-4 minutes, and high-frequency heating to a temperature of 180-200°C and kept warm for 1.5-3 minutes. The equipment pressure is 2300T (tons); the compression rate of the wood board increases step by step after each hot press treatment in the hot pressing sequence, and the compression rates of the wood board are 30-40%, 40-50% and 50-60% respectively; the second time interval between the end of hot pressing in the previous hot press and the start of hot pressing in the next hot press is 20-30 seconds.

[0088] 3) Water-cooled cold pressing treatment: the load-bearing components after hot pressing enter four water-cooled cold presses for cold pressing, and each water-cooled cold press is cold pressed for 3-6 minutes in sequence. The temperature of the wood board decreases step by step after each water-cooled cold press according to the cold pressing sequence, and the temperature of the wood board after each cold press is 160-180℃, 140-160℃, 120-140℃, and 100-120℃ respectively; the pressure of the water-cooled cold pressing equipment is 2300T (tons), and the compression rate of the wood board increases step by step after each water-cooled cold press according to the water-cooled cold pressing sequence, and the compression rate of the wood board increases by 3-5% at each level; the third time interval between the end of cold pressing of the load-bearing component in the previous water-cooled cold press and the beginning of cold pressing of the next water-cooled cold press is 20-30 seconds.

[0089] 4) Saturated water-cooled pressing: After the cold pressing treatment, the load-bearing components enter the water-cooled pressing equipment line for cold pressing and curing. The equipment pressure is 60T, the processing time is 25-35min, and the average temperature of the wood board is cooled to 70-80℃.

[0090] Example 2

[0091] The steps of Example 1 are the same, except for the preheating treatment in step 1). The improved process steps are as follows:

[0092] 1) Preheating treatment: The load-bearing components enter three preheating machines in sequence for preheating, and are heated at high-frequency heating temperature of 80-90℃ for 8-12s, high-frequency heating temperature of 100-110℃ for 8-12s, and high-frequency heating temperature of 120-130℃ for 4-6s. The compression rate of the wood board increases step by step after being treated by each preheating machine in the hot pressing sequence, and the compression rates of the wood board are 15-20%, 20-25% and 25-30% respectively; the first time of the heating interval between adjacent high-frequency preheating machines is 5-20 seconds.

[0093] According to the method of the above-mentioned embodiment 2, the wood is compacted according to the specific parameter settings below, and the temperature of the wood board mentioned below refers to the temperature at which the wood board is heated in the equipment to a set temperature.

[0094] Table 1 Parameters of the progressive high-frequency compaction method provided by Example 2-1, Example 2-2, and Example 2-3

[0095]

[0096]

[0097] Example 3

[0098] The progressive wake-up wood type high-frequency compaction method further includes the following steps based on the steps in Example 2:

[0099] 5) Air cooling treatment: The air cooling technology is used to treat the wood board after saturated water cooling and pressing. The surface temperature of the wood board after air cooling is lower than 60℃, the wind temperature is 10℃-15℃, and the wind speed is 20m / s-25m / s.

[0100] 6) Curing treatment: The load-bearing components after air cooling are transferred to the curing equipment and balanced at room temperature for 11-13 days.

[0101] Control test example 1

[0102] The compacted wood is prepared according to steps 1)-4) of the method described in Example 2, except that the equipment for the preheating treatment, high-frequency hot pressing treatment and water-cooled cold pressing wood awakening treatment steps are connected in series without any intervals, and each equipment directly enters the next equipment after treatment without any release space; the parameters used by the equipment are consistent with the parameters described in Example 1-1.

[0103] The process steps 1)-4) are specifically as follows:

[0104] 1) Preheating treatment: The load-bearing components are sequentially preheated in three high-frequency preheating machines connected in series without intervals. The high-frequency heating is maintained for 20 seconds, and the temperature of the wood board reaches 120-130°C, making the compression rate of the wood board 30%.

[0105] 2) High-frequency hot pressing treatment: The preheated load-bearing components are sequentially entered into three hot presses connected in series without intervals for hot pressing. High-frequency pressurization is maintained for 8 minutes. The temperature of the wood board reaches 180-200°C, and the equipment pressure is 2300T (tons), so that the compression rate of the wood board is 60%.

[0106] 3) Water-cooled cold pressing treatment: The load-bearing components after hot pressing treatment enter four water-cooled cold presses connected in series without intervals for cold pressing. High-frequency water cooling is maintained for 8 minutes. The temperature of the board reaches 100-120℃, and the equipment pressure is 2300T (tons), making the compression rate of the board 72%.

[0107] 4) Saturated water-cooled pressing: After the cold pressing treatment, the load-bearing components enter the water-cooled pressing equipment line for cold pressing and curing. The equipment pressure is 60T, the processing time is 25-35min, and the average temperature of the wood board is cooled to 75℃.

[0108] Example 4

[0109] The load-bearing member of the present invention is processed by the method of Example 1 of CN 111421633 A (published on July 17, 2020), except that step 2) "heating and compression treatment", step 3) "curing treatment" and step 4) "cooling treatment" are set as progressive treatment in the assembly line equipment of the present invention. It should be noted that the number of high-frequency hot press equipment is adjusted and set on the assembly line according to the steps required. The specific method is as follows:

[0110] 1) Pretreatment: Pretreat the wood board with density ρ=0.6, control the average moisture content of the wood board to 10%, and place the wood board in the shallow groove of the pallet to form a load-bearing component.

[0111] 2) Heating and compression treatment: The pretreated load-bearing components enter three high-frequency hot presses in sequence for hot pressing, and are respectively subjected to high-frequency heating at 100°C for 2.5 min, high-frequency heating at 100°C for 2.5 min, and high-frequency heating at 100°C for 2 min. The adjacent high-frequency heating sub-steps are spaced 20 seconds apart; the compression rates of the wooden boards are 41%, 43% and 45% respectively.

[0112] 3) Curing treatment: the load-bearing components after hot pressing are sequentially put into three high-frequency hot presses for hot pressing, and are respectively subjected to high-frequency heating at 180°C for 3 min, high-frequency heating at 180°C for 3 min, and high-frequency heating at 180°C for 2 min. The second time interval between adjacent high-frequency heating sub-steps is 20 seconds.

[0113] 4) Cooling treatment: The solidified load-bearing components are sequentially cooled in four water-cooled cold presses until the average temperature of the wood board is 70°C. The compression rate of the wood board is maintained at 45% after each cold press. The third time interval between the cold presses of adjacent water-cooled cold presses is 20 seconds.

[0114] 5) Curing treatment: Place the cooled wood on a horizontal drying surface and apply a pressure of 5.5 MPa to the upper surface of the wood. After curing for 3 days, reduce the pressure by 1.2 MPa every day until the pressure is 0, and continue curing for 10 days.

[0115] Control test example 2

[0116] The load-bearing component of the present invention is processed by the method of Example 1 of CN 111421633 A (publication date: July 17, 2020), that is, the pretreated wooden board is placed in the shallow groove of the pallet to form the load-bearing component; at the same time, a non-progressive equipment such as the high-frequency compaction equipment of CN109454721A (2019.03.12) is used to perform high-frequency compaction on the load-bearing component.

[0117] Example 5

[0118] The load-bearing member of the present invention is processed by the method of Example 1 of CN 103753664A (2014.4.30), except that: Steps 2) to 5) are set as progressive processing in the assembly line equipment of the present invention. It should be noted that the number of high-frequency hot press equipment is adjusted and set on the assembly line according to the steps required. The specific method is as follows:

[0119] 1) Pretreatment: Pretreatment of a wood board with a density of ρ = 0.6, controlling the average moisture content of the wood board to 18%, placing the wood board in a shallow groove of a pallet to form a load-bearing component. The load-bearing component is preheated on a high-frequency hot press at a preheating temperature of 180°C and a preheating time of 2s.

[0120] 2) The preheated load-bearing components are subjected to the first high-frequency hot pressing treatment. The load-bearing components are sequentially put into three hot presses for hot pressing, and are sequentially subjected to high-frequency heating at 100°C for 2 min, high-frequency heating at 100°C for 2 min, and high-frequency heating at 100°C for 1 min; adjacent high-frequency heating sub-steps are spaced 20 seconds apart.

[0121] 3) The heated load-bearing components are sequentially put into three high-frequency hot presses for hot pressing, and are sequentially subjected to high-frequency heating at 140°C for 2 minutes, high-frequency heating at 160°C for 2 minutes, and high-frequency heating at 180°C for 2 minutes. The interval between adjacent high-frequency heating sub-steps is 20 seconds; the compression rates of the wood boards are 40%, 45%, and 50% respectively. 。

[0122] 4) The compressed load-bearing components are subjected to a second high-frequency hot pressing treatment. The load-bearing components are sequentially put into three hot presses for hot pressing, and are sequentially subjected to high-frequency heating at 180°C for 8 min, high-frequency heating at 180°C for 7 min, and high-frequency heating at 180°C for 7 min; adjacent high-frequency heating sub-steps are spaced 20 seconds apart.

[0123] 5) The load-bearing components enter four water-cooled cold presses in sequence for cooling until the average temperature of the wood board is 60°C. The compression rate of the wood board is maintained at 50% after each cold press; the third time interval between the cold presses of adjacent water-cooled cold presses is 20 seconds.

[0124] Control test example 3

[0125] The load-bearing member of the present invention is processed by the method of Example 1 of CN 103753664A (2014.4.30), that is, the pre-treated wooden board is placed in the shallow groove of the pallet to form the load-bearing member; at the same time, a non-progressive device such as the high-frequency compaction device of CN109454721A (2019.03.12) is used to perform high-frequency compaction on the load-bearing member. The non-progressive device described in this embodiment is compared with the technical solution of the present invention in which a docking movable track is set between multiple heating and compaction devices, and there is no docking movable track between the devices.

[0126] Test comparison results

[0127] 1. Comparison of anti-rebound between the progressive high-frequency compaction method and the known high-frequency compaction method

[0128] Referring to GB / T 1934.1-2009 "Determination of water absorption of wood", Example 1, Example 2-1, Example 2-2, Example 2-1 and Control Test Example 1, Example 4 and Control Test Example 2, Example 5 and Control Test Example 2 were measured; the average water absorption rate (%), water absorption rate difference (%) and water absorption thickness expansion rate (%) of the provided compacted wood board in 6 hours were as shown in Table 3. The average water absorption rate is the average value of each water absorption rate measured on the upper and lower surfaces of the compacted wood board with thicknesses of 2 cm, 4 cm, 5 cm, 6 cm and 8 cm, respectively (when measuring the water absorption rate of a specific thickness, it can be processed by cutting or punching, and then measured); the water absorption rate difference is the difference between the maximum and minimum values ​​of the measured water absorption rates; water absorption thickness expansion rate (%) = (thickness before immersion - thickness after immersion) / thickness before immersion.

[0129] Table 3 Water absorption test results of the compressed wood boards prepared by the above methods

[0130]

[0131]

[0132] The average water absorption rate (%) of the high-frequency compacted wood of Example 1, Example 2-1, Example 2-2, Example 2-1 and Control Example 1 for 6 hours is lower than 0.70%, and the water absorption rate difference (%) and water absorption thickness expansion rate (%) are much better than the various indicators of Control Example 1.

[0133] The average water absorption rate (%) of the high-frequency compacted wood of Example 4 for 6 hours is 0.70%, the water absorption rate difference (%) is 0.23%, and the water absorption thickness expansion rate (%) is 0.47%, which is better than the indicators of Example 1 of CN 111421633 A (2020, 07, 17), among which the water absorption thickness expansion rate (%) is reduced by about half. The indicators of the comparative test example 2 lag behind those of the example 4, which shows that when using the load-bearing member of the present invention, the progressive method steps can better solve the rebound problem.

[0134] The 6h average water absorption rate (%), water absorption rate difference (%) and water absorption thickness expansion rate (%) of the high-frequency compacted wood of Example 5 are much better than those of the control test example 3, which also proves that the load-bearing structure of the present invention is suitable for the progressive compaction method.

[0135] The main chemical components of wood are cellulose, hemicellulose and lignin (three major elements). If a large number of hydrogen bonds are formed among cellulose, hemicellulose and lignin in the compacted wood, the compacted wood will not rebound easily compared to other wood. The progressive high-frequency compaction method of the present invention, which includes multiple high-frequency heating sub-steps, multiple compression and densification sub-steps and / or multiple rapid cooling steps, can allow cellulose molecules, hemicellulose molecules and lignin molecules to interweave and stretch multiple times, forming a larger number of hydrogen bonds with each other. In addition, the microstructure of the three major elements is more closely interwoven, which can better lock water molecules, so that the high-frequency compacted wood can better resist the destruction of hydrogen bonds by moisture when absorbing moisture. The above is the principle of the present invention.

[0136] 2. Comparison of production efficiency between the progressive wake-up wood high-frequency compaction method and the known high-frequency compaction method

[0137] The static working point of the assembly line refers to the working position in each working unit of the assembly line where the load-bearing components need to stay and be processed in the working unit instead of flowing. For example, when the wood is heated by a high-frequency medium heating device, or when the wood is compressed and compacted as a whole by a hydraulic press, the load-bearing components need to stay at the working position and be processed, and cannot continue to flow.

[0138] The dynamic working point of the assembly line refers to the working position in each operating unit of the assembly line that can flow through without the need for load-bearing components to stay in the operating unit for processing, such as the air-cooled roller section, the curing roller section, etc.

[0139] By comparing the method of the embodiment of the present invention with the process of CN 111421633 A (2020, 07, 17), it can be seen that since the embodiment of the present invention splits the "high-frequency heating step" into multiple high-frequency heating sub-steps, and splits the "compression and densification step" into multiple compression and densification sub-steps, and since the production line is a cyclic operation, and the "high-frequency heating step" and the "compression and densification step" are both static working points of the assembly line, the progressive wake-up wood type high-frequency compaction method of the embodiment has a production efficiency improved by more than 3 times compared with the existing high-frequency compaction method.

[0140] The "progressive high-frequency compaction method" of the present invention is based on the "high-frequency compaction method", and a high-frequency heating step that needs to be completed at one time is split into multiple high-frequency heating sub-steps at intervals of a certain time to be completed gradually, and a compression and densification step that needs to be completed at one time is split into multiple compression and densification sub-steps at intervals of a certain time to be completed gradually, or a rapid cooling step that needs to be completed at one time is split into multiple rapid cooling steps at intervals of a certain time to be completed gradually. During the "certain time interval", the process applied to the wood in the corresponding step, such as heating, pressurization and water cooling, is released. The "progressive high-frequency compaction method" of the present invention is very suitable for being configured on the "progressive high-frequency compaction equipment" of the present invention. The "progressive high-frequency compaction equipment" of the present invention can maintain the mechanical properties of the wood board compaction and avoid rebound through equipment and equipment technology under the premise of simplifying the load-bearing components.

[0141] The above technical solution is only one implementation mode of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the principles disclosed in the present invention, and it is not limited to the technical solution described in the above specific embodiments of the present invention. Therefore, the above description is only preferred and does not have a restrictive meaning.

Claims

1. A progressive wake-up wood type high-frequency compaction production line, including operating equipment and bearing components, characterized in that: The operating equipment comprises a preheating part, a high-frequency hot pressing part and a water-cooled cold pressing wood awakening part connected in sequence; The high-frequency hot pressing part includes a plurality of high-frequency hot pressing machines, the second movable roller of each high-frequency hot pressing machine extends from the internal hot pressing station toward the inlet and outlet on both sides and is exposed, and the exposed second movable rollers of adjacent high-frequency hot pressing machines are butted; The water-cooled cold-pressing wake-up wood part includes a plurality of water-cooled cold presses, and the third movable roller of each water-cooled cold press extends from the internal pressing station toward the inlet and outlet on both sides and is exposed, and the exposed third movable rollers of adjacent water-cooled cold presses are butt-jointed; The bearing member comprises a pallet and a wooden board carried by the pallet. When the bearing member is supported and moved by a movable roller, the thickness direction of the wooden board is not constrained by the operating device.

2. The progressive wake-up wood type high-frequency compaction production line according to claim 1 is characterized in that: The preheating section comprises a plurality of preheating machines, and the first movable roller of each preheating machine extends from the internal preheating station toward the inlet and outlet on both sides and is exposed, and the exposed first movable rollers of adjacent preheating machines are butted against each other.

3. The progressive wake-up wood type high frequency compaction production line as claimed in claim 1, characterized in that: The operating equipment also includes a loading section, a saturated water-cooled pressing section, a first conveying section, a second conveying section, an air-cooled roller section, a curing roller section and a discharge section; The loading section, preheating section, high-frequency hot pressing section, water-cooled cold pressing section and saturated water-cooled pressing section are arranged in sequence on a first straight line in a forward direction; the air-cooled roller section, curing roller section and unloading section are arranged in sequence on a second straight line in a reverse direction, one side of the first conveying section is arranged on the downstream side of the saturated water-cooled pressing section, and the other side is arranged on the upstream side of the air-cooled roller section; one side of the second conveying section is arranged on the downstream side of the unloading section, and the other side is arranged on the upstream side of the loading section.

4. The progressive wake-up wood type high frequency compaction production line as claimed in claim 3, characterized in that: The loading part includes a wood board loading platform, a movable roller platform and a wood board picking mechanism; One side of the wood board loading platform is docked with the mobile roller platform. The wood board loading platform is a translation roller, which is used to transport the wood boards to the side of the mobile roller platform. The wood board picking mechanism is arranged on the top of the mobile roller platform, and extends from the upstream side of the mobile roller platform to the upper side of the docking side of the wood board loading platform. The wood board picking mechanism adopts a suction cylinder and an air nozzle. The unloading section includes a unloading moving roller platform and a unloading picking mechanism; the unloading picking mechanism is arranged on the top of the unloading moving roller platform, and extends on the upstream side of the moving roller platform to above the moving roller near the downstream side of the health roller section; the downstream end of the health roller section is connected to the second conveying section; the unloading picking mechanism adopts a suction cylinder and an air nozzle.

5. The progressive wake-up wood type high frequency compaction production line as claimed in claim 3, characterized in that: The first conveying section is longitudinally arranged at the downstream side of the saturated water-cooled pressing section of the multiple lines, and at the same time, the other end side of the saturated water-cooled pressing section is butted against the upstream roller of the air-cooled roller section, and a mechanical pusher is arranged at this end to push the wooden board to the air-cooled roller section; the first conveying section is a longitudinal moving platform, which is used to longitudinally move the water-cooled wooden board to one end of the air-cooled roller section; The second conveying section is longitudinally arranged and has one side connected to the downstream end of the curing roller section and the side of the feeding section away from the preheating section; A mechanical pusher is provided at the joint with the side of the loading part to push the tray onto the moving roller platform of the loading part.

6. The progressive wake-up wood type high frequency compaction production line as claimed in claim 3, characterized in that: A plurality of first straight lines arranged in parallel can be arranged between the loading section and the first conveying section, and the preheating section, the high-frequency hot pressing section, the water-cooled cold pressing section and the saturated water-cooled pressing section are arranged in sequence on each of the first straight lines.

7. The progressive wake-up wood type high frequency compaction production line as claimed in claim 1, characterized in that: The surface of the pallet facing the wooden board is provided with a shallow groove whose shape matches the shape of the wooden board. The surface of the pallet facing the wooden board is provided with a water diversion groove in the horizontal and / or vertical direction. The water diversion hole that runs through the entire pallet is provided at the position of the water diversion groove.

8. A compaction method using the progressive wake-up wood type high-frequency compaction line according to claim 1, characterized in that: The method comprises at least the following steps: High-frequency hot pressing treatment: The preheated load-bearing components are sequentially put into several hot presses for multiple hot pressings. The compression rate of the wood board increases step by step after hot pressing in each hot press according to the hot pressing sequence; the second time from the end of hot pressing in the previous hot press to the start of hot pressing in the next hot press is 20-30 seconds; Water-cooled cold pressing wake-up wood treatment: the load-bearing components after hot pressing treatment enter several water-cooled cold presses in sequence for multiple water-cooled cold pressings. The temperature of the wood board decreases step by step after each water-cooled cold press according to the cold pressing sequence, and the compression rate of the wood board increases step by step after each water-cooled cold press according to the water-cooled cold pressing sequence; the interval from the end of cold pressing in the previous water-cooled cold press to the start of cold pressing in the next water-cooled cold press is 20-30 seconds.

9. The progressive wake-up wood type high frequency compaction production line as claimed in claim 8, characterized in that: The high-frequency hot pressing step also includes a preheating treatment: the load-bearing component enters several preheating machines in sequence for multiple preheating, and the first time from the end of preheating of the previous preheating machine to the start of preheating of the next preheating machine is 5 to 20 seconds.

10. A compaction method using the progressive wake-up wood type high-frequency compaction line according to claim 1, characterized in that: The method comprises the following steps: 1) Preheating treatment: The load-bearing components are sequentially preheated in three preheating machines, and are respectively heated at a high-frequency heating temperature of 80-90°C for 8-12s, a high-frequency heating temperature of 100-110°C for 8-12s, and a high-frequency heating temperature of 120-130°C for 4-6s. The compression rate of the wood board increases step by step after being treated by each preheating machine in the hot pressing sequence, and the compression rates of the wood board are 15-20%, 20-25% and 25-30% respectively; the first time of the heating interval between adjacent high-frequency preheating machines is 5-20 seconds; 2) High-frequency hot pressing treatment: the preheated load-bearing components are sequentially put into three hot presses for hot pressing, and are respectively subjected to high-frequency heating to 140-160°C for 2-4 minutes, high-frequency heating to 160-180°C for 2-4 minutes, and high-frequency heating to 180-200°C for 1.5-3 minutes. The compression rate of the wood board increases step by step after each hot press treatment according to the hot pressing sequence, and the compression rates of the wood board are 30-40%, 40-50% and 50-60% respectively; the second time interval between the end of hot pressing of the previous hot press and the start of hot pressing of the next hot press is 20-30 seconds; 3) Water-cooled cold pressing treatment: the load-bearing components after hot pressing enter four water-cooled cold presses for cold pressing, and each water-cooled cold press is cold pressed for 3-6 minutes in sequence. The temperature of the wood board decreases step by step after each water-cooled cold press according to the cold pressing sequence. The temperature of the wood board after each cold press is 160-180℃, 140-160℃, 120-140℃, and 100-120℃ respectively; the compression rate of the wood board increases step by step after each water-cooled cold press according to the water-cooled cold pressing sequence, and the compression rate of the wood board increases by 3-5% at each level; the third time interval between the end of the cold pressing of the load-bearing component in the previous water-cooled cold press and the start of the cold pressing of the next water-cooled cold press is 20-30 seconds; 4) Saturated water-cooled pressing: After the cold pressing treatment, the load-bearing components enter the water-cooled pressing equipment line for cold pressing and curing. The equipment pressure is 60T, the processing time is 25-35min, and the average temperature of the wood board is cooled to 70-80℃.

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