硬质合金圆锯片开细缝的研究

研究了锯身开有细缝的硬质合金圆锯片。对比试验表明，细缝硬质合金圆锯片较常规硬质合金圆锯片的优点是：空转偏摆小、高频固有频率数量少，吸振效果好，噪声低。     

无料圆锯片的初步研究

分析了无料圆锯片的发热因素，说明了无料圆锯片的应用可能性，并提出了具体的技术条件。     

夹盘直径对圆锯片固有频率的影响

将未适张、辊压适张、锤击适张圆锯片装在不同直径的夹盘上，施以相同的夹紧力后进行振动模态分析。实验证明，不论是未适张圆锯片，还是辊压和锤击适张圆锯片，随着夹盘增大，锯片各阶固有频率都有不同程度的提高，其中辊压适张圆锯片二阶振动模态的固有频率没有增加或只有少量增加，锤击适张圆锯片四阶以上振动模态的固有频率有显著增加。     

开槽圆锯片热变形的试验研究

本文研究了圆锯片径向槽的数量、长度、宽度对圆锯片热变形的影响。试验结果发现，三者对圆锯片的热变形均有较大的影响：当开5个径向槽时圆锯片的热变形最小；相同条件下，径向槽相对较长的锯片不易发生热变形；径向槽宽度的增加可引起锯片热变形的加剧。     

割灌机圆锯片的齿形齿参数及锉磨方法

割灌机圆锯片对齿尖高度一致性的要求很高，圆锯片孔和定位垫圈孔的安装间隙可能引起的偏心必须予以考虑。文章提出了符合切削原理且经生产实践验证的齿形参数推荐值，并论述了锉磨的具体方法。     

基于ABAQUS的圆锯片切削竹筒仿真试验研究

为降低伐竹机械工作过程中所受切削力，寻找最优切削参数组合，基于ABAQUS对圆锯片结构进行约束模态分析，对切削竹筒过程进行仿真模拟。通过单因素试验研究了圆锯片转速Vc、进给速度Vf、切削倾角θ和齿数Z对峰值切削力的影响，并以上述4个因素为影响因素，峰值切削力为评价指标进行正交试验以获得优化参数组合。结果表明：峰值切削力随着转速、进给速度和切削倾角的增加先减小后增大，随着齿数的增加而减小。当圆锯片转速为3 000 r/min、进给速度为0.2 m/s、倾斜角度为10°、齿数为40 T时，可在一定程度上降低圆锯片所受切削力，并且切削断面平整。研究结论可为伐竹机械的设计提供参考。     

基于ANSYS的圆锯片模态分析和振动分析

利用ANSYS有限元软件,通过对圆锯片的模态分析,研究其低频范围的横向振动问题.通过软件分析得出圆锯片相应模态下的固有频率和振型.并利用动态信号测试分析系统对圆锯片相应模态的固有频率进行检测,得出圆锯片的固有频率与节圆数和节径数的变化规律,圆锯片边缘的位移矢量和与节圆数、节径数的关系,并指出在不了解圆锯片弹性模量、泊松比和密度等参数的条件下利用动态信号测试分析系统对圆锯片的模态进行检测具有一定的可行性.     

木材低切削量锯切中圆锯片组在线冷却系统的研制

在圆锯片组锯切过程中，高速旋转的锯片与工件发生摩擦会产生大量的切削热。当圆锯片温度过高时，其振动急剧增加，变形增大，严重影响加工精度和出材率，而且存在安全隐患，为此设计了木材锯切冷却介质制冷雾化在线冷却系统。介绍了该系统的结构、工作原理、主要技术参数及系统设计。     

温度与离心力载荷对不同基体结构圆锯片横向刚度的影响

横向刚度是影响圆锯片锯切过程稳定性的重要因素。以四种具有代表性的圆锯片基体结构为研究对象,利用非线性有限元法建立其力学模型,研究在温度、离心力载荷单独作用以及两者共同作用下,圆锯片横向刚度的变化规律。结果表明:随着圆锯片外缘温度的升高,其横向刚度呈下降趋势;离心力载荷可提升圆锯片的横向刚度;圆锯片基体结构对于其横向刚度随圆锯片外缘温度的变化规律具有影响。     

圆锯片激光冲击适张过程的理论建模与分析

【目的】利用激光冲击手段对圆锯片进行适张处理,以探寻圆锯片适张应力场的生成与调控机制,拓宽圆锯片的适张手段。【方法】在合理简化与假设的基础上,利用ABAQUS非线性有限元分析软件建立圆锯片激光冲击适张过程的理论分析模型;采用静态应变采集仪测量圆锯片激光冲击适张后的应力场。【结果】当激光脉宽小于20 ns时,圆锯片外缘的切向适张拉应力随激光冲击波峰值压力增加而增大;当激光脉宽大于等于20 ns时,圆锯片外缘的切向拉应力随激光冲击波峰值压力增加呈先增大后减小的趋势;当激光冲击波峰值压力为6 GPa左右时,圆锯片外缘的切向拉应力达到最大值。【结论】圆锯片激光冲击适张后,外缘生成一定量级的切向拉应力;激光脉宽与冲击波峰值压力对圆锯片外缘的切向拉应力具有不同程度影响;在最优激光冲击波峰值压力作用下,圆锯片外缘的切向拉应力达到最大值。圆锯片激光冲击适张工艺具备可行性,通过激光工艺参数的调整能够调节圆锯片的适张程度。     

木工圆锯片锯齿侧刃参数对锯切表面粗糙度的影响

【目的】分析锯齿侧刃参数对锯切表面粗糙度的影响,通过优化锯齿侧刃参数,解决圆锯锯切时进给速度提高与表面粗糙度增大之间的矛盾,为新型木工圆锯片设计提供参考和指导。【方法】提出微量零径向侧后角锯齿的概念,使用9种不同锯齿侧刃参数的圆锯片,以水曲柳和高密度纤维板为对象进行锯切试验,研究不同进给速度下径向侧后角和零径向侧后角段对锯切表面粗糙度的影响。【结果】随着进给速度增加,锯切表面粗糙度增大,径向侧后角减小,锯切表面粗糙度降低,无零径向侧后角段锯齿锯切形成的表面粗糙度均高于具有零径向侧后角段锯齿,特别是当零径向侧后角段由0 mm增加到0.5 mm时,锯切表面粗糙度下降最为明显。当零径向侧后角段大于0.5 mm时,侧刃的零径向侧后角段具有"以锯代刨"的作用,与零径向侧后角锯齿相比同样可起到改善锯切表面质量的作用。【结论】锯切表面粗糙度一定程度上取决于锯痕深度。在实际锯切过程中,仅有长度近似等于每齿进给量的锯齿侧刃部分参与切削,占侧刃总长度的很小一部分,微量零径向侧后角锯齿中零径向侧后角段长度比每齿进给量略大且越接近每齿进给量越理想。具有微量零径向侧后角段锯齿的圆锯片与零径向侧后角锯齿相比,同样可起到改善锯切表面质量的作用;在保持其他切削参数不变的情况下,微量零径向侧后角段锯齿还可以减小锯齿侧刃与锯路壁之间的摩擦。     

带锯机锯轮转速、锯条摆动与锯解精度的试验研究

基于对木工带锯机加工特性的研究需要,本文在MJ397型高速木工带锯机的锯条张紧力和进给速度恒定的情况下,通过实测锯机工作台和锯条结构系统的固有频率、同条件下锯割杉木试材时的锯条横向摆动量、变频器调节锯轮转速和锯材表面粗糙度等,分析锯轮转速、锯条横向摆动量与锯解精度的关系,为优化国产带锯机锯割稳定性等设计工作提供依据.     

MR5412型圆锯片气焊加热适张度机工艺与设备的研究

加热适张度是利用氧一乙炔焰,将锯身的一定部位加热,使该部在冷却收缩中产生同辊压张力一样的变形,从而获得适张度。圆锯片气焊加热适张度机配有带锯夹锯装置,可用于圆、带锯的加热适张度及辊压处理,实现了一机多用。经该机修整的锯片,具有作业时间短、适张度均匀且不易消失,锯末端加热部分不易变形,厚度均匀,锯切质量高等优点。     

The effect of rotation speed on the power consumption and cutting accuracy of guided circular saw: Experimental measurement and analysis of saw critical and flutter speeds

ABSTRACT

This paper investigates the effect of rotation speed and vibration response of a circular saw on the sawing process of Douglas-fir wood. An idling test was conducted on a guided circular saw to determine its stable operation speeds and vibration behavior. Short-time Fourier transform analysis was performed on saw idling test data, and variation of excited frequencies of the blade as a function of rotation speed was obtained. The saw blade critical speeds and the rotation speeds that correspond to saw flutter instability were identified. Then experimental cutting tests were conducted at different cutting conditions and the effect of rotation speed and saw vibration response on cutting power consumption and sawing accuracy was investigated. The results showed that conducting a saw idling test and vibration response analysis can identify the saw critical and flutter speeds, which is essential for identifying the optimum rotation speed of circular saw. There was a significant increase in power consumption when cutting at super-critical and super-flutter speed. The effect of rotation speed on sawing accuracy is complex and nonlinear. This effect interacts with feed speed, which makes it difficult to generalize sawing accuracy versus rotation speed in the circular sawing process.     

木质材料无屑切削机理及切削力的研究

对木质材料切削中比较特殊的一类切削方式———无屑切削的切削机理及切削力进行了理论上的研究,并在单板切条试验机上进行试验验证。研究证明,楔型刀锯进行木质材料无屑切削时,其切削力受木材的树种、切削方向、锯片尺寸、角度参数及切削用量的影响较大。     

锯片锯料角对锯切表面粗糙度影响机理分析

分析了锯料角影响锯切表面粗糙度的机理，阐述了锯料角与锯料量对锯切表面粗糙度的影响。分析结果表明，只要锯料角不变化，则锯料量的变化对锯切表面粗糙度不起任何作用。锯料角影响锯切表面粗糙度的机理为开发新型锯片、提高锯切表面的质量和锯切效率提供依据。     

Some possibilities for reducing circular saw idling noise

The sound pressure level of differently designed circular saw blades were investigated during idling. Nine blade samples were used: three differently designed blade bodies (without slots, with four radial slots, and with four slots with copper cork), each with three diameters (260,280, and 300 mm). The sound pressure level was measured at different rotational frequencies ranging from 25 to 65 rps in increments of 1 rps. Rubber damping rings 80mm in diameter and 0.3 mm thick were placed between the saw blade and the collars, and the emitted noise was measured. Because of the whistling sound the blades without slots emitted high sound pressure levels. There were no significant changes when rubber damping rings were used. The use of rubber damping rings on the samples with radial slots eliminates the whistling noise. The saws with copper corks did not emit a whistling noise at all, and their aerodynamic noise was 2–3 dB (A) lower than the aerodynamic noise of the saws with radial slots. The relation between sound pressure emitted by the damped idling saw and peripheral velocity can be described by the power function with the exponent value between 4.8 and 5.2.Part of this report was presented at the 14th International Wood Machining Seminar, Epinal, France, September 1999     

Deviations of kerf by handsaws III: the bend of saw blade by unsymmetrical set

To clarify the inducing mechanism of kerf deviation caused by unsymmetrical set of the handsaw, we hypothesized that the moment on the bottom edge of the saw blade, which is generated by the unsymmetrical set on handsaw teeth, bends the saw blade and this deformation should be one factor of the kerf deviation. To verify this hypothesis, the bend of a saw blade was examined by experiment and by calculation. In the experiments, a model tooth was attached to an actual handsaw. In the calculations, a saw model with a rectangular prism as the model tooth was analyzed by the finite element method. Loads were applied on the model tooth or the rectangular prism. From both the experiments and the calculations, the following results were obtained: (1) the deformation of the handsaw was caused by the unsymmetrical set in the length direction and the height direction of the saw blade; (2) the deformation and the inclination of the blade was larger at the front part of the saw than at the butt part; and (3) comparing the saw handle fixing conditions, the kerf deviation in the sawing line was supposed to be larger in the free handle condition and that kerf deviation in the depth direction was larger in the fixed handle condition. Based on the above results, it is apparent that one of the kerf deviation mechanisms originated from unsymmetrical set on the saw teeth. Part of this report was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, Japan, August 2004.     

铜对圆锯片热应力的影响与研究

通过锯切木材试验,分别对锯身槽上嵌铜和不嵌铜设计的同条件下木工圆锯片,进行定点温度、横向摆动量和噪声参数的测量;并结合有限元热应力场分布与计算,以及铜材理化试验分析等手段,得出其嵌铜锯片消除热应力性能好,振声性能较高,锯片使用寿命延长等结论,并提出减振降噪的措施与建议,为优化圆锯片的设计工作提供参考依据。     

圆锯片适张状态检测方法的研究(英文)

文章论述了一种圆锯片适张状态的检测方法及实现的系统 .该方法采用锯片适张前后固有频率的变化幅度 ,锯片单点加载情况下一定半径圆周上的横向变形量和端面圆跳动三个特征参量 ,表述一个锯片的适张程度、适张均匀性和平整性 .应用计算机控制的检测系统 ,经过对大量不同规格木工锯片和大型金刚石锯片的检测 ,结果表明该方法是切实可行的