整体硬质合金螺旋木工铣刀的合理选用

从刀具旋向特点、加工方式、切削参数以及刀具磨损等方面介绍整体硬质合金螺旋木工铣刀的应用和选择。     

基于有限元的大型枝丫粉碎机切削力分析

对枝丫粉碎机的切削力进行研究,推导出切削力的计算公式,找出影响切削力的因素,并对受切削力作用的飞刀进行ANSYS有限元分析。     

几种竹材径向剖篾机型的分析比较

通过选用几种不同机型的竹材径向剖篾机,对竹材的不同切削形式、不同刀头结构,分步与同步剖篾方式,以及剖篾效率与竹篾质量等多方面进行分析比较,认为刨切式多刀分步径向剖篾机具有结构合理、剖篾效率高、径向竹篾厚度精度高、表面粗糙度小的优点,具有较好的推广应用前景。     

齿轮倒角机刚柔耦合模型建模及仿真研究

采用混合建模的仿真分析方法,运用机械造型软件Pro-E和多体动力学仿真软件ADAMS建立倒角机的刚柔耦合虚拟样机模型,并对其进行具体的仿真分析。研究结果表明,使用硬质合金刀具,齿轮倒角机在工作时震动小,工作较平稳;仿真分析过程中,选择最少2个旋转分布的铣刀片已能得出仿真数据且保证其精度,增加铣刀数目会带来建模困难和降低仿真速度。该建模方法和仿真分析对齿轮倒角机结构的优化设计提供依据。     

数控超高压水切割机床的工件夹紧装置研究设计

基于提高超高压水射流切割机床加工木材和木质复合材料质量需要,依据动力学实验原理,以杉木为试件,采用动压力测试方法分别对杉木工件在自由状态下切割受力情况和对不同规格的杉木工件在自由状态与夹紧状态下的切割表面粗糙度进行了对比试验研究,并以此设计了与SQ-WJG40型高压水射流切割机床相配套的四气缸联动气压夹紧装置.     

履带式割灌机通过性能仿真研究

灌木为生物质能源的重要原材料,灌木生长的沙地环境对割灌设备的通过性能有较高的要求,为此利用虚拟样机软件ADAMS的履带车辆分析工具箱(ADAMS tracked vehicle)对履带割灌机在四种不同地形情况下的通过性能进行仿真试验分析,预测履带式割灌机的通过性能。     

Changes in the anatomy of surface and liquid uptake of wood after laser incising

The effects of laser incising on the surface of heat-affected zones (HAZs) and liquid uptake of wood were examined. Deep pin holes were incised on the tangential section of the wood with a laser beam of 1 kW in power with varied pulse widths, and the HAZs of the holes were investigated using scanning electron microscopy. The length of liquid uptake passing through HAZs surfaces was then measured. It was observed that the HAZs were unable to maintain normal porous structure, and smooth surfaces such as that of wood charcoal were also not observed. This is because the composite of the middle lamella completely melted, which led to a decrease in the length of liquid uptake. In addition, the release of high gas-pressure and thermal energy during the laser-incising process did not damage the tylose and the aspirated pit in the longitudinal direction. Because of this, the liquid movement remained blocked. However, the incising holes provided additional liquid-intake points, resulting in greater intake capacity. Moreover, it was observed that improvement of liquid impregnation is related to hole diameter.     

Milling of wood and wood-based materials with a computerized numerically controlled router IV: development of automatic measurement system for cutting edge profile of throw-away type straight bit

In industrial machining of timber, the method in which the operator visually inspects both wear and chippings of router bits after stopping the machine is generally adopted. However, many working hours are lost in this method and productivity suffers. Therefore, the development of a system that can automatically measure wear or chippings without stopping the machine is desirable. In this study, a laser measuring instrument was installed in a computerized numerically controlled (CNC) router, and an automatic measurement system for the cutting edge profile of throw-away-type straight bits with single-edged blades was developed. The main results are summarized as follows: (1) an automatic measurement system for the cutting edge profile of the bit was constructed; (2) this system was composed of a laser measuring instrument, a control personal computer (PC) for the CNC router, and a monitoring PC to control some devices and collect sampling data; (3) the system could measure the cutting edge profile of the bit without stopping the CNC router.Part of this article was presented at the 51st and 52nd Annual Meetings of the Japan Wood Research Society, Tokyo and Gifu, April 2001 and 2002, respectively     

木工螺旋齿圆柱铣刀运动力学特性分析

螺旋齿圆柱铣刀在高速切削木材时会出现崩刃和折断等现象,且小直径长铣刀此类问题尤为明显,为此对螺旋齿圆柱铣刀铣削加工时的运动力学特性进行分析研究。建立螺旋齿圆柱铣刀的矩阵方程,获得铣刀铣削运动轨迹,并明确了铣削加工方式;利用ADAMS分析不同铣削参数对螺旋齿圆柱铣刀切入过程的影响,得到不同铣削参数下螺旋齿圆柱铣刀所受冲击载荷随时间的变化曲线;运用ANSYS Workbench瞬态动力学分析,明确了铣削切入工件时螺旋齿圆柱铣刀的瞬时应力大小和分布情况,为螺旋圆柱铣削加工确定最佳铣削参数提供理论依据。     

基于三维表面形貌测定法的水切割木竹材工艺参数优化

为优化木竹材超高压水射流切割加工工艺参数,以红橡木和竹地板为对象,采用正交试验法,研究磨料流速、切割压力、进给速度、靶距对水射流加工试件表面粗糙度的影响,探索优化工艺参数。利用扫描探针式三维表面形貌测定法测量试件切割面的表面粗糙度值,分析三维表面形貌图。结果表明:红橡木磨料射流的试验影响因素排序为CADB;竹地板磨料射流的试验影响因素排序为BCAD。红橡木和竹地板优化工艺参数为:进给速度为250 mm/s,磨料流速为35 kg/h,靶距3 mm,切割压力为310 MPa。在此加工工艺条件下切割材料表面粗糙度相对较小,加工所得材料品质较好。     

赤桉、巨尾桉扦插育苗成活率试验

试验结果表明：不同浓度的ＡＢＴ生根粉液对扦插成活牵有显著影响，以２５０×１０－６ＡＢＴ生根粉液处理效果最好；扦插条硬枝、嫩枝对扦插成活率有影响，嫩枝扦插条成活率高于硬枝扦插；巨尾桉比赤桉更易扦插成活；扦插条有或无顶芽，对扦插成活影响不大；高温、高湿天气有利于扦插条成活。     

Rectangularity of planed Scots pine (Pinus sylvestris) planks

Abstract

This study deals with how warp affects the cross-sectional shape of planed planks. A total of 20 planks with dry target cross-sectional dimensions of 50×150 mm were planed to 45×145 mm. The rectangularity of five cross sections of every plank was measured before and after planing. The cutting depths were measured in 10 positions in the cross sections, and the angles between the planks and the cutters were calculated. Also, the warp, that is, twist, bow, crook, and cup, was measured before and after planing. All the studied properties pointed in the same direction. In terms of both rectangularity and angles of cut, the problems were larger in the top and butt ends of the investigated planks than in the intermediate parts, and the main reason for deviations from the desired result after planing was twist.     

Experiments on decolourization with 122 resin for extraction of gibberellins from solid medium under different conditions

The extracting liquid of gibberellins (Gibberella fujikurol) from solid medium for was decolorized separately with 75%,95% alcohol, and distilled water in static adsorption and vibrating way for different durations. The results showed that the content of GA3 in efflux extracted with alcohol is 10% higher than that with distilled water. With the increase of the durations of extraction,the content of GA3 increases and the dissolution of pigments also increase. For extraction of GA3 cultured in solid medium, the best decolorizing result was obtained when it was extracted with 75%-95% alcohol in static way for 1-3 h, or in a vibrating way for 30-60 min, and then to decolor in a static way for 30-60 min in 122 resin column.     

木材水导纳秒激光加工设备设计与试验

传统木材激光加工技术容易使木材表面产生严重的烧蚀现象并带有残炭等残留物,造成木制品外观和表面质量较差,针对这一系列问题,提出木材水射流辅助激光加工技术,根据拟定的设备总体方案,设计木材水导纳秒激光加工设备,并对其进行加工试验。结果表明:设备设计较为合理,当厚度为2 mm、切割速度为50 mm/s、激光功率为6 W时,水曲柳表面切缝宽度仅为0.18 mm,切缝表面质量较好。     

木工榫槽铣刀的固有频率测试研究

分别采用随机激励功率谱和声学测量法测试木工榫槽铣刀的固有频率。结果表明，两种测试方法皆可行且安全可靠。对木工榫槽铣刀固有频率的测试研究可为木工榫槽铣刀设计与优化提供借鉴。     

Airborne laser scanning-based decision support for wood procurement planning

We present a decision support tool for guiding the selection of marked stands based on airborne laser scanning (ALS) data. We describe three stages, namely (1) wall-to-wall mapping of the stands matured for cutting using low-density ALS data; (2) tree-level inventory of these stands using high-density ALS data and (3) theoretical bucking of the imputed tree stems to produce detailed information on their characteristics. We tested them in a Scots pine dominated boreal forest area in Eastern Finland, where 79 sample plots were measured in the field. The detection of the stands matured for cutting had a success rate of 95% and our results demonstrated a further potential to limit the result towards stands dominated by certain species by means of intensity values derived from the low-density ALS data. The applied single-tree detection and estimation chain produced detailed tree-level information and realistic diameter distributions, yet the detection was highly emphasised on the dominant tree layer. The error levels in the estimates were generally less than standard deviations of the field attributes. Finally, plot-level accumulations of saw-log volumes were found rather similar, whether the input was based on the imputed tree data or trees measured in the field. The results are considered useful for ranking the stands based on their properties, whether the aim in the wood procurement is to focus on certain species or to select stands suitable for production needs.     

一种基于图像处理的旋切原木直径测量方法

【目的】提出一种基于图像处理的旋切原木直径测量方法,为旋切原木直径测量提供非接触式的技术支持。【方法】增添650nm红色激光器和940nm不可见激光器作为辅助光源,采用树莓派官方摄像头和带有滤光片装置的USB高清工业摄像头进行图像采集,利用图像处理技术探究5种计算方法(计算激光线下弧线像素点个数、计算激光线骨架像素点个数、计算激光线周长像素点个数取平均值、计算激光线X轴方向像素点个数和通过激光线计算拟合圆直径)和6种数据拟合方法(傅里叶拟合、指数拟合、高斯拟合、Polynomial拟合、Power拟合和SumofSine拟合)下能够满足测量精度的最优方案。【结果】对比各计算方法采用不同数据拟合方法的拟合优度,可得到拟合优度最佳的2种方案:计算激光线X轴方向像素点个数并采用SumofSine拟合方法,其决定系数为0.9998,标准差为1.638;计算激光线X轴方向像素点个数并采用傅里叶拟合方法,其决定系数为0.9998,标准差为1.881。在原木测量误差分析中对拟合优度相差较小的2种方法(傅里叶拟合和SumofSine拟合)进一步对比,傅里叶拟合的平均绝对误差范围为1.7%,标准差为2.11,方差为4.45;SumofSine拟合的平均绝对误差范围为1.5%,标准差为4.35,方差为18.95。【结论】计算激光线X轴方向像素点个数并采用傅里叶拟合方法,在满足旋切机用原木直径测量精度要求的同时,拟合优度最佳。     

基于UG的木工铣刀CAD系统设计

以UG为支撑平台,利用Visual C 6.0、SQL Server和UG二次开发工具UG/Open研制开发了现代木工铣刀CAD系统.该系统界面友好,集现有木工铣刀查询、选型、设计计算和三维建模于一体,同时又具备良好的可扩展性和可移植性.实践证明该系统极大地提高了现代木工铣刀的设计效率和精度.     

影响桉树插穗生根的几个因素研究

通过6年的桉树扦插育苗研究，总结出影响插穗生根有6个因素：（1）母株来源，组培苗作母株的插穗比扦插苗作母株的生根状况好；（2）母株年龄，母株在1-3年生时采穗条扦插生根率高；（3）穗龄，桉树穗条上长有3-4对成熟叶时扦插成活率高；（4）穗条留叶面积，在扦插不良季节，桉树扦穗留叶至1/3面积的生根率最高，而地扦插良好季节，桉树插穗留叶至2/3面积生根率最高；（5）扦插季节，桉树扦插最佳季节为每年的11月份至次年的4月份；（6）植物生长调节剂，吲哚丁酸（IBA）作生根激素使用效果比萘乙酸（NAA）好。     

高速加工中影响平面铣削精度因素浅析

阐述了高速加工中影响平面铣削精度的几方面要素,介绍了在粗铣、半精铣及精铣条件下如何选择铣刀,分析了冷却方式及涂层材料对刀具的影响,对铣削效率加以综合评价并提供了相关计算公式。