Semicircular bamboo wood flattening device

Abstract

According to the semicircular bamboo wood flattening device, the whole semicircular bamboo wood can be continuously flattened at a time, the operation efficiency is high, bamboo chips are not cracked, and the utilization rate of the bamboo wood is increased. The device comprises a rack, a gradual change type working table, a radial pressurizing device, a tangential pressurizing device and a conveying system, the feeding end of the gradually-changed working table is in a semi-arc shape, and when the gradually-changed working table extends towards the discharging end, the arc is gradually flattened till the discharging end is completely a plane. The conveying system comprises a plurality of pairs of rollers and a conveying driving device, a plurality of open holes are formed in the working table top from the front (feeding section) to the rear (discharging section), and a pair of rollers is arranged above and below each open hole; the radial pressurizing device comprises an arc-shaped pressing ring and a plurality of small rotating pressing rollers arranged on the pressing ring, and the gap between each small pressing roller and the upper surface of the opposite working table is not larger than the thickness of the bamboo wood. The tangential pressurizing device applies pressure to the thickness faces on the two sides of the bamboo in the tangential direction of the arc of the bamboo, and circumferential pressing of the arc bamboo is achieved through the tangential pressurizing device and the working table.

Description

Technical Field

[0001] The present invention relates to the technical field of bamboo flattening, and specifically to a semi-circular bamboo flattening device. Background Art

[0002] Commonly used longitudinal flattening of semi-circular long bamboo can obtain flat bamboo with a long strip and wide width. The continuous flattening method is a commonly used flattening method. The existing continuous method is to make incisions with a certain depth on the bamboo yellow surface, causing the bamboo yellow surface to relax, and then relatively roll along the length direction of the bamboo on both the bamboo yellow and bamboo green surfaces to flatten the bamboo. However, when processing subsequently, the incisions need to be planed off, resulting in a large waste, increasing the complexity of the process and equipment, and the utilization rate of bamboo is low. There are also those that do not make incisions on the bamboo yellow surface and directly flatten, such as CN1820917A. First, the bamboo is processed into a certain length, and after removing the internal nodes, it is transversely rolled. However, the flattened bamboo still has a large arc and needs to be further flattened, which easily causes the bamboo to crack, and the length is limited, and the entire bamboo cannot be flattened. Summary of the Invention

[0003] The present invention provides a semi-circular bamboo flattening device, which can continuously flatten the entire long semi-circular bamboo at one time, is not limited by the length of the bamboo, has high working efficiency, and the flattened bamboo slices have no cracks, improving the utilization rate of bamboo.

[0004] To achieve the above technical purpose, the technical solution adopted by the present invention is as follows:

[0005] The semi-circular bamboo flattening device includes a frame, a gradually changing workbench surface, a radial pressing device, a tangential pressing device, and a conveying system are arranged on the frame;

[0006] The workbench surface is gradually changing. Its front end, i.e., the feeding end, is semi-circular arc-shaped, and when extending backward to the discharging end, the arc gradually flattens until the discharging end is completely flat; the conveying system for driving the bamboo to move forward includes multiple pairs of rollers and a conveying driving device for driving the upper roller or the lower roller to rotate. Each pair of rollers includes an upper roller and a lower roller; a plurality of openings are arranged on the workbench surface from front to back. A pair of rollers is arranged up and down at each opening position. The convex surface (bamboo green surface) of the bamboo is attached to the upper surface of the workbench surface, and the bamboo passes through between the upper roller and the lower roller of each pair of rollers and is pressed by the upper roller and the lower roller. The rotation of the upper and lower rollers drives the bamboo to move forward;

[0007] A plurality of radial pressing devices are arranged above the workbench surface from front to back. The radial pressing device includes an arc-shaped pressing ring and a plurality of small pressing rollers rotatably arranged on the pressing ring. The gap between the small pressing roller and the upper surface of the opposite workbench surface is not greater than the thickness of the bamboo;

[0008] A plurality of tangential pressing devices are symmetrically arranged on both sides of the workbench surface from front to back. The symmetric tangential pressing devices act on the thickness surfaces on both sides of the bamboo material, applying pressure to the bamboo material in the tangential direction of the bamboo arc, and together with the workbench surface, realizing circumferential pressure on the arc surface of the bamboo material.

[0009] As an improvement, the outer periphery of the lower roller in the conveying device is a concave arc surface along the direction of its rolling axis, and the outer periphery of the upper roller is a convex arc surface along the direction of its rolling axis. The concave arc surface of the lower roller is flush with the arc surface on the upper surface of the workbench surface; from the feeding end to the discharging end, in each pair of rollers, the length of the generatrix of the concave arc surface of the lower roller and the length of the generatrix of the convex arc surface of the upper roller gradually increase.

[0010] As an improvement, grooves are provided on the concave arc surface of the lower roller in the conveying device, and the extending direction of the grooves is consistent with the direction of the rolling axis of the lower roller.

[0011] As an improvement, along the workbench surface from front to back, the lengths of each opening and each pair of rollers increase in the direction of the rolling axis of the rollers. The upper roller is a driving roller connected to the conveying driving device and is made of heat-resistant rubber or plastic.

[0012] As an improvement, an elastic element is arranged between the pressing ring and the frame. In the normal state, the elastic element makes the pressing ring approach the workbench surface, and each small pressing roller presses the bamboo material tightly on the workbench surface.

[0013] As an improvement, the same pressing ring is connected by a plurality of pressing roller shafts, and a rotating small pressing roller is arranged on each pressing roller shaft; both ends of each small pressing roller shaft are respectively hinged on a pressing rod, and an elastic element is arranged between each pressing rod and the frame. In the normal state, the elastic element makes each pressing rod and the pressing roller shaft approach the workbench surface, and each small pressing roller presses the bamboo material tightly on the workbench surface and realizes the unfolding of the arc surface of the bamboo material.

[0014] As an improvement, the arc surface at the upper surface of the workbench surface opposite to each pressing ring is a concentric circle.

[0015] As an improvement, the tangential pressing device includes a hydraulic cylinder hinged on the frame and a side pressing roller. The end of the piston rod extending out of the hydraulic cylinder is rotatably provided with the side pressing roller; the side pressing roller is coaxial with the piston rod, and the end face of the side pressing roller contacts the thickness surfaces on both sides of the bamboo material. The radius of the side pressing roller is not less than the thickness of the bamboo material, the outer peripheral surface of the side pressing roller contacts the upper surface of the workbench surface, and the part of the end face of the side pressing roller close to the upper surface of the workbench surface contacts the thickness surfaces on both sides of the bamboo material.

[0016] As an improvement, the tangential pressing device includes a second hydraulic cylinder hinged to the frame and a second side pressing roller. The end of the piston rod of the second hydraulic cylinder is provided with a rotatable second side pressing roller (for example, a second fixed bracket is fixed at the end of the piston rod, the shaft of the second side pressing roller is fixed on the second bracket, and the second side pressing roller is rotatably arranged on the shaft of the second side pressing roller); the outer periphery of the second side pressing roller contacts the thickness surfaces on both sides of the bamboo, and the rotation axis of the second side pressing roller is perpendicular to the axis of the bamboo.

[0017] As an improvement, the tangential pressing device further includes an oil pressure detection device for detecting the hydraulic oil pressure in the first hydraulic cylinder and the second hydraulic cylinder. When the first side pressing roller and the second side pressing roller contact and press the thickness surfaces on both sides of the bamboo, the hydraulic oil pressure remains unchanged.

[0018] As an improvement, it further includes a photoelectric detection device arranged in front of each tangential pressing device for detecting the chord height of the semi-circular bamboo about to enter the workbench surface where the tangential pressing device is located. The photoelectric detection device is electrically connected to the controller, the controller is electrically connected to the hydraulic valve controlling the actions of the first hydraulic cylinder and the second hydraulic cylinder, and a hydraulic valve is arranged on the hydraulic pipeline communicating with the first hydraulic cylinder and the second hydraulic cylinder; the controller controls the telescopic movement of the piston rod of the first hydraulic cylinder and the piston rod of the second hydraulic cylinder according to the chord height of the semi-circular bamboo: when the bamboo has not reached the workbench surface where the first side pressing roller and the second side pressing roller are located, the piston rod and the piston rod are in the retracted state and will not interfere with the movement of the bamboo; when the bamboo reaches the workbench surface where the first side pressing roller and the second side pressing roller are located, the piston rod and the piston rod extend, and the thickness surfaces of the bamboo are pressed by the first side pressing roller and the second side pressing roller.

[0019] The beneficial effects of the present invention are as follows:

[0020] The semi-circular whole bamboo with inner nodes removed and softened is fed into the workbench surface from the feeding end of the workbench surface and is clamped by a pair of rollers near the feeding end, namely the upper roller and the lower roller. Then, under the action of the conveying system, the bamboo moves from front to back along the workbench surface. During the movement, under the action of the small pressing roller, the outer arc surface (bamboo green surface) of the bamboo always fits the upper surface of the workbench surface, and the bamboo is gradually flattened; at the same time, the tangential pressing device presses the bamboo along the tangential (circumferential) direction of the bamboo arc surface. Since the bamboo yellow surface of the bamboo will be stretched during the flattening process by the small pressing roller and the rollers, in order to prevent excessive stretching and cracking due to uneven stretching of each point on the arc of the bamboo yellow surface, the tangential pressing plays a role in pressing the circumference of the bamboo arc, that is, pressing along the tangential direction of the bamboo arc, compressing the bamboo circumferentially. The bamboo green surface will be compressed more, while the bamboo yellow surface will be compressed less, preventing the bamboo yellow surface from cracking due to excessive stretching during the flattening process of the arc-shaped bamboo.

[0021] The workbench surface is a non-planar structure. One end (the head end, the feeding end) is semi-circular arc-shaped, and when extending towards the other end (the tail end, the discharging end), the arc gradually flattens until it becomes completely planar. A plurality of openings are provided in the workbench surface, and a pair of rollers are arranged above and below each opening position. The middle of the lower roller length is a concave arc surface, and a groove is provided on the concave arc surface of the lower roller. The length direction of the groove is the same as the length direction of the roller (the rolling axis direction) to increase the friction when conveying bamboo. The concave arc surface of the lower roller is flush with the upper surface arc of the workbench surface. The upper roller is made of heat-resistant rubber or plastic (because the softened semi-circular bamboo is in a high-temperature state). The length of the roller at the feeding end is smaller, and from the feeding end to the tail end, as the arc of the round bamboo gradually becomes flatter, the length of the roller increases (of course, the length of each opening on the workbench surface also increases) to increase the friction on the bamboo and at the same time increase the pressing on the flattened surface of the bamboo.

[0022] The clearance distance between the small pressing roller on the pressing ring and the upper surface of the workbench surface is not greater than the thickness of the bamboo, which facilitates the arc-shaped bamboo to pass through the clearance and can apply a certain pressure to the bamboo so that the bamboo fits the arc surface of the workbench, realizing the progressive unfolding of the arc surface of the bamboo. The radian of the pressing ring at different front and rear positions above the workbench surface also changes, the same as the radian of the workbench surface, but the arc surface at the upper surface of the workbench corresponding to each pressing ring is a concentric circle. The small pressing roller and the workbench surface together play a role in restricting the arc of the bamboo. When the bamboo passes through the clearance from the arc end (feeding end) of the workbench surface to the tail end, it will change with the change of the arc between the arc surface of the workbench surface and the small pressing roller on the pressing ring, and finally be pressed and unfolded into a planar shape. The pressing ring can apply pressure to different bamboos, so that the bamboo is pressed and attached to the arc-shaped workbench surface as soon as it enters the workbench surface, making the bamboo in a unfolded state. Due to the thickness difference of the bamboo wall, the thin wall of the small end of the bamboo near the bamboo tip and the thick wall of the big end of the bamboo near the bamboo root. If the clearance distance remains unchanged, the radial pressure on the bamboo changes with the change of the bamboo thickness, and it is possible that the thinner-walled bamboo does not receive radial pressure. Therefore, an elastic element such as a spring is installed on the radial pressing device to adjust the clearance size, and the radial pressure on the thin-walled bamboo can be realized, so that the thin-walled bamboo can also fit well on the changing workbench surface.

[0023] The bamboo also has a taper. The diameter and chord height of the semi-circular bamboo change with the length. The arc length and chord height of the part near the bamboo root are large, and the arc length and chord height of the part near the bamboo tip are small. In order to be able to apply an effective tangential force to the side surface (thickness surface) of the bamboo, an oil pressure detection and control device (such as a pressure gauge and a control valve) is provided for the hydraulic cylinder and the second hydraulic cylinder of the tangential pressing device. When the arc diameter of the bamboo is larger, the extending lengths of the piston rod and the second piston rod are shorter, and vice versa. The oil pressure detection and control device can sense the pressure change and expand and contract according to the change of the chord height of the bamboo arc contacted by the side pressing roller and the second side pressing roller, realizing the continuous and effective tangential pressure on the bamboo wall.

[0024] The diameters of different bamboo materials are all variable. When a bamboo material passes through a certain tangential pressing device, at the position where the next bamboo material is about to pass through this device, due to the different diameters of the bamboo materials, the chord heights of the semi-circular bamboo materials are different. In order not to prevent the next bamboo material from moving to the workbench surface position where the tangential pressing device is located (at this position) and passing through smoothly, this requires the tangential pressing device to be lifted in advance in a timely manner. And after the next bamboo material moves to the workbench surface where the tangential pressing device is located, the tangential pressing device can quickly press down to exert pressure on the side surface (thickness surface) of the bamboo material. Therefore, an optoelectronic detection device for detecting the chord height of the semi-circular bamboo material about to enter the front end of the workbench is arranged in front of the front end of the workbench. The controller controls the telescopic movement of the piston rod of the hydraulic cylinder and the piston rod two of the second hydraulic cylinder according to the chord height of the semi-circular bamboo material. Optoelectronic detection devices are also arranged in front of other tangential pressing device positions, and the purpose is the same. Lifting and pressing-down times are set for each tangential pressing device, so that the tangential pressing devices at different positions can be lifted up in sequence and then quickly pressed down.

[0025] The tangential pressing devices do not all press vertically downward. At different positions, the tangential pressing devices change with the arc of the workbench surface. From the feeding end, they are vertically placed and press the bamboo material vertically, and to the discharging end, as the arc of the bamboo slices gradually becomes flat, the pressing devices are approximately horizontally placed and press the bamboo material approximately horizontally.

[0026] The conveying device consists of multiple pairs of upper and lower rollers. The length direction of the lower rollers is concave arc-shaped. The arc of the concave arc surface of the lower roller near the feeding end of the workbench surface is the largest, and the arc of the concave arc surface of the lower rollers at different positions from the feeding end to the discharging end gradually becomes flat. The upper rollers are rubber or plastic rollers, and the gap between the upper rollers and the lower rollers is the thickness of the bamboo material. The lengths of the rollers at different positions from the feeding end to the discharging end are continuously increasing.

[0027] The present invention can continuously and crack-free unfold a whole long semi-circular bamboo material, improve the utilization rate of bamboo materials, and the process is continuous with relatively high operation efficiency.

[0028] The softening of bamboo materials belongs to conventional technology, and the softening temperature and time are well-known. After softening, the internal nodes of the bamboo are removed so that the bamboo materials can be smoothly conveyed and move along the workbench surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a front view schematic diagram of the semi-circular bamboo material flattening device.

[0030] Figure 2 It is a top view schematic diagram of the semi-circular bamboo material flattening device.

[0031] Figure 3 It is a schematic diagram of the workbench surface, tangential pressing device, etc. at cross-sections at different positions from front to back.

[0032] Figure 4 Schematic diagrams of the workbench surface, radial pressing device, etc. at cross-sections in different positions from front to back.

[0033] Figure 5 Side view schematic diagram of the semi-circular bamboo flattening device (feeding end).

[0034] Figure 6 Schematic diagram when the tangential pressing device presses on the thickness surface of the bamboo.

[0035] In the figure, there are workbench surface 1, feeding end 11, discharging end 12, and opening 13.

[0036] Radial pressing device 2, pressure ring 21, small pressing roller 22, pressing roller shaft 23, pressing rod 24, spring 25.

[0037] Tangential pressing device 3, hydraulic cylinder 31, piston rod 32, side pressing roller 33.

[0038] Conveying system 4, upper roller 41, lower roller 42, conveying driving device 43, concave arc surface 44 of the lower roller.

[0039] Photoelectric travel switch 5, frame 6.

[0040] Bamboo 100, thickness surface 101 of the bamboo. Specific implementation manners

[0041] The following further explains the specific implementation manners of the present invention according to the accompanying drawings:

[0042] The whole long semi-circular bamboo flattening device of the present invention unfolds the semi-circular bamboo to improve the utilization width and utilization rate of the bamboo. It includes frame 6, and a progressive workbench surface 1, radial pressing device 2, tangential pressing device 3, conveying system 4, photoelectric travel switch 5, etc. are arranged on the frame.

[0043] The front end of the progressive workbench surface 1, i.e., the feeding end 11, is semi-circular arc-shaped, and the arc gradually becomes flattened when extending towards the rear end, i.e., the discharging end 12, until the discharging end is completely flat. A plurality of openings 13 are arranged in the middle of the workbench surface from front to back.

[0044] The conveying system 4 for driving the bamboo to move from front to back includes multiple pairs of rollers and a conveying driving device 43 for driving the upper roller 41 or the lower roller 42 to rotate. Each pair of rollers includes an upper roller and a lower roller; a pair of rollers is arranged above and below each opening position. The middle of the outer circumference of the lower roller along its rolling axis direction (length direction) is a concave arc surface 44, and the concave arc surface of the lower roller is flush with the arc surface on the upper surface of the workbench. Grooves are provided on the concave arc surface 44 of the lower roller, and the extending direction of the grooves is consistent with the rolling axis direction of the lower roller.

[0045] Along the working table surface from front to back, the lengths of the openings 13 and the pairs of roller wheels (upper roller wheel 41 and lower roller wheel 42) increase in the direction of the roller wheel rolling axis. The upper roller wheel 41 is a driving roller connected to the conveying drive device 43 and is made of heat-resistant rubber or heat-resistant plastic.

[0046] The convex (bamboo green) surface of the inner-node softened bamboo material 100 is attached to the upper surface (concave surface) of the working table surface 1, and the bamboo material 100 passes through between the upper roller wheel 41 and the lower roller wheel 42 in each pair of roller wheels and is pressed by the upper roller wheel 41 and the lower roller wheel 42. The convex (bamboo green) surface of the bamboo material 100 contacts the concave arc surface 44 of the lower roller wheel 42, and the concave (bamboo yellow) surface of the bamboo material 100 contacts the convex arc surface of the upper roller wheel 41. In each pair of roller wheels, the lengths of the generatrices of the concave arc surface 44 of the lower roller wheel 42 and the convex arc surface of the upper roller wheel 41 also vary. The length of the generatrix near the feeding end is the shortest. As the bamboo material travels from the feeding end to the discharging end, the lengths of the generatrices of the concave arc surface 44 of the lower roller wheel 42 and the convex arc surface of the upper roller wheel 41 become longer, and the length of the generatrix near the discharging end is the longest.

[0047] A plurality of radial pressing devices 2 are arranged above the working table surface from front to back. The radial pressing device includes an arc-shaped pressing ring 21, small pressing rollers 22, pressing roller shafts 23, pressing rods 24, springs 25, etc. The pressing ring 21 is sequentially connected by a plurality of pressing roller shafts 23, and a rotating small pressing roller 22 is arranged on each pressing roller shaft 23; both ends of each pressing roller shaft are respectively hinged on a pressing rod 24. Each pressing rod 24 is slidably connected to the frame 6, and a spring 25 is arranged between each pressing rod and the frame. In the normal state, the spring 25 makes each pressing rod 24 and the pressing roller shaft 23 approach the upper surface of the working table surface, and each small pressing roller 22 presses the bamboo material against the upper surface of the working table surface. Each pressing ring is basically arc-shaped, and the arc surface at the upper surface of the working table surface opposite to the pressing ring is basically a concentric circle.

[0048] A plurality of tangential pressing devices 3 are symmetrically arranged on both sides of the working table surface from front to back. The symmetric tangential pressing devices act on the thickness surfaces at both ends of the cross-sectional arc of the bamboo material and press the bamboo material in the tangential direction of the bamboo arc. The tangential pressing device 3 includes a hydraulic cylinder 31 with the upper end hinged on the frames on both sides of the working table surface, a hydraulic pipeline provided with a hydraulic valve, an oil pressure detection and control device for detecting and controlling the hydraulic oil pressure in the hydraulic cylinder, and a side pressing roller 33, etc. A rotatable side pressing roller 33 is rotatably arranged at the end of the piston rod 32 extending out of the hydraulic cylinder 31; the side pressing roller 33 is coaxial with the piston rod 32, the radius of the side pressing roller 33 is not less than the thickness of the bamboo material 100, the outer peripheral surface of the side pressing roller contacts the upper surface of the edge of the working table surface, and the part of the end surface of the side pressing roller close to the upper surface of the working table surface contacts the bamboo thickness surface 101 on the side of the bamboo material 100.

[0049] Of course, tangential pressure devices with other structures can also be adopted. For example, another tangential pressure device includes a second hydraulic cylinder whose upper end is hinged to the frames on both sides of the workbench surface, a hydraulic pipeline provided with a hydraulic valve, an oil pressure detection and control device for detecting and controlling the hydraulic oil pressure in the second hydraulic cylinder, and a second side pressure roller. The end of the piston rod of the second hydraulic cylinder extends out to fix a second bracket, the second side pressure roller shaft is fixed on the second bracket, and the second side pressure roller is rotatably arranged on the second side pressure roller shaft. The outer circumference of the second side pressure roller contacts the thickness surfaces 101 on both sides of the bamboo, and the rotation axis of the second side pressure roller is perpendicular to the axis of the bamboo.

[0050] The photoelectric travel switch 5 as the photoelectric detection device is arranged in front of the front end of the workbench surface and is used to detect the chord height and arrival time of the semi-circular bamboo 100 about to enter the front end of the workbench surface. The photoelectric travel switch 5 is electrically connected to the controller, and the controller is electrically connected to the hydraulic valve that controls the actions of the hydraulic cylinder and the second hydraulic cylinder. The controller controls the telescoping of the piston rod 32 of the hydraulic cylinder 31 and the piston rod of the second hydraulic cylinder according to the chord height and arrival time of the semi-circular bamboo: when the bamboo 100 has not reached the workbench surface where the side pressure roller 33 and the second side pressure roller are located, the piston rod 32 and the piston rod are in the retracted state and will not interfere with the movement of the bamboo; when the bamboo reaches the workbench surface where the side pressure roller 33 and the second side pressure roller are located, the piston rod 32 and the piston rod extend out, and the thickness surface 101 of the bamboo is pressurized through the side pressure roller 33 or the second side pressure roller. When the side pressure roller 33 or the second side pressure roller contacts and presses on the thickness surfaces on both sides of the bamboo, the hydraulic oil pressure remains unchanged.

[0051] The present invention provides a semi-circular bamboo flattening device, which can continuously flatten a whole semi-circular bamboo at one time, with high working efficiency, no cracking of bamboo slices, and improved utilization rate of bamboo. It includes a frame, a gradually changing workbench surface, a radial pressure device, a tangential pressure device and a conveying system; the feeding end of the gradually changing workbench surface is semi-circular arc-shaped, and the arc gradually flattens when extending towards the discharging end until the discharging end is completely flat; the conveying system includes multiple pairs of rollers and a conveying driving device, and a plurality of openings are arranged on the workbench surface from front (feeding section) to back (discharging section), and a pair of rollers are arranged up and down at each opening position; a plurality of radial pressure devices are arranged above the workbench surface from front to back, and the pressing rings in the radial pressure devices change from small to large as the arc surface of the workbench surface changes from small to large, so as to flatten the arc surface of the bamboo. The radial pressure device includes an arc-shaped pressing ring and a plurality of rotating small pressing rollers arranged on the pressing ring, and the gap between the small pressing roller and the upper surface of the opposite workbench surface is not greater than the thickness of the bamboo; a plurality of symmetric tangential pressure devices are arranged on both sides of the gradually changing workbench surface from front to back, and the tangential pressure device applies pressure to the thickness surfaces on both sides of the bamboo along the tangential direction of the bamboo arc, and together with the workbench surface, it realizes the circumferential pressing of the arc-shaped bamboo to prevent the bamboo yellow surface from cracking due to uneven stretching of the arc surface during the flattening process.

[0052] The protection scope of the present invention includes but is not limited to the above embodiments. The protection scope of the present invention shall be subject to the claims, and any replacement, variation, or improvement that is easily conceivable by those skilled in the art for this technology shall fall within the protection scope of the present invention.

Claims

1. Semi-circular bamboo flattening device, characterized in that: It includes a frame, on which a workbench surface, a radial pressing device, a tangential pressing device and a conveying system are provided; The workbench surface is of a gradually changing type. Its front end, i.e., the feeding end, is semi-circular arc-shaped. When extending towards the rear end, i.e., the discharging end, the arc gradually flattens until the discharging end is completely flat. The conveying system used to drive the bamboo material that has been softened and had its internal joints removed to move from the feeding end to the discharging end includes multiple pairs of upper and lower rollers located on the gradually changing workbench surface and a conveying driving device for driving the upper rollers or the lower rollers to rotate. Each pair of rollers includes an upper roller and a lower roller. A plurality of openings are provided on the workbench surface from front to back. A pair of rollers is arranged above and below each opening position. The convex surface of the bamboo material, i.e., the bamboo green surface, fits with the upper surface of the workbench surface, and the bamboo material passes through between the upper roller and the lower roller of each pair of rollers and is pressed by the upper roller and the lower roller. The purpose of setting the rollers and the conveying driving device is to play a role in conveying and flattening during the flattening process of the semi-circular bamboo material; A plurality of radial pressing devices are provided above the workbench surface from front to back. The radial pressing device includes an arc-shaped pressing ring and a plurality of rotating small pressing rollers provided on the pressing ring. The gap between the small pressing rollers and the upper surface of the opposite workbench surface is not greater than the thickness of the bamboo material. The arc of the pressing ring in the radial pressing device changes from small to large as the arc surface of the workbench surface changes from small to large. The purpose of setting the radial pressing device is to make the semi-circular arc-shaped bamboo material closely fit to the workbench surface and achieve the flattening of the arc surface of the bamboo material; A plurality of tangential pressing devices are symmetrically arranged on both sides of the workbench surface from front to back. The symmetric tangential pressing devices act on the thickness surfaces on both sides of the bamboo material and press the bamboo material in the tangential direction of the bamboo arc, and together with the workbench surface, achieve the circumferential pressing of the semi-circular arc bamboo material.

2. The semi-circular bamboo flattening device according to claim 1, characterized in that: The outer circumference of the lower roller is a concave arc surface along the direction of its rolling axis, and the outer circumference of the upper roller is a convex arc surface along the direction of its rolling axis. The concave arc surface of the lower roller is flush with the arc surface of the upper surface of the gradually changing workbench surface; from the feeding end to the discharging end, in each pair of rollers, the length of the generatrix of the concave arc surface of the lower roller and the length of the generatrix of the convex arc surface of the upper roller gradually increase.

3. The semi-circular bamboo flattening device according to claim 1, characterized in that: Grooves are provided on the concave arc surface of the lower roller, and the extending direction of the grooves is the same as the direction of the rolling axis of the lower roller.

4. The semi-circular bamboo flattening device according to claim 1, characterized in that: An elastic element is provided between the pressing ring and the frame. In the normal state, this elastic element makes the pressing ring approach the workbench surface, and each small pressing roller presses the arc-shaped bamboo material against the workbench surface.

5. The semi-circular bamboo flattening device according to claim 1, characterized in that: The same pressing ring is connected by a plurality of roller shafts. Small pressing rollers are rotatably arranged on each roller shaft; both ends of each roller shaft are respectively hinged on a pressing rod. An elastic element is provided between each pressing rod and the frame. In the normal state, this elastic element makes each pressing rod and the roller shaft approach the workbench surface, and each small pressing roller presses the bamboo material against the workbench surface.

6. The semi-circular bamboo flattening device according to claim 1, wherein: The arc surface at the upper surface of the workbench surface opposite to each pressing ring is a concentric circle.

7. The semi-circular bamboo flattening device according to claim 1, wherein: The tangential pressing device includes a hydraulic cylinder hinged on the frame and a side pressing roller. A rotating side pressing roller is provided at the end of the piston rod extending out of the hydraulic cylinder; the side pressing roller is coaxial with the piston rod, and the end surface of the side pressing roller contacts the thickness surfaces on both sides of the bamboo material; the radius of the side pressing roller is greater than the thickness of the bamboo material, the outer peripheral surface of the side pressing roller contacts the upper surface of the workbench surface, and the edge part of the end surface of the side pressing roller close to the upper surface of the workbench surface contacts the thickness surfaces on both sides of the bamboo material.

8. The semi-circular bamboo flattening device according to claim 1, wherein: The tangential pressing device includes a second hydraulic cylinder hinged to the frame and a second side pressing roller. The end of the piston rod of the second hydraulic cylinder is provided with a rotatable second side pressing roller. The outer circumference of the second side pressing roller contacts the thickness surfaces on both sides of the bamboo, and the rotation axis of the second side pressing roller is perpendicular to the axis of the bamboo.

9. The semi-circular bamboo flattening device according to claim 7 or 8, characterized in that: The tangential pressing device further includes an oil pressure detection device for detecting the pressure of the hydraulic oil in the hydraulic cylinder. When the side pressing roller contacts the thickness surfaces on both sides of the bamboo and applies pressure, the pressure of the hydraulic oil remains unchanged.

10. The semi-circular bamboo flattening device according to claim 7 or 8, characterized in that: It further includes a photoelectric detection device arranged in front of each tangential pressing device for detecting the chord height of the semi-circular bamboo about to enter the workbench surface where the tangential pressing device is located. The photoelectric detection device is electrically connected to the controller, the controller is electrically connected to the hydraulic valve controlling the action of the hydraulic cylinder, and a hydraulic valve is arranged on the hydraulic pipeline communicating with the hydraulic cylinder. The controller controls the telescopic movement of the piston rod of the hydraulic cylinder according to the chord height of the semi-circular bamboo: when the bamboo has not reached the workbench surface where the side pressing roller is located, the tangential pressing piston rod is in the retracted state and will not interfere with the movement of the bamboo; when the bamboo reaches the workbench surface where the side pressing roller is located, the piston rod extends, and the side pressing roller at the end of the piston rod presses the thickness surface of the bamboo to realize circumferential pressing on the arc-shaped bamboo.

Images