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     

圆锯片适张度量化分析方法的研究

从研究、选取表征锯片适张状态主要指标——适张度的特征参量入手，研究开发了一种以８０３１单片机为主体，以基２复序列ＦＦＴ算法为核心的锯片适张度检测系统。运用该系统对国内外几十种不同规格锯片的实测结果表明，该方法及研制开发的检测系统运用于工业现场是切实可行的。     

采用半有限元法分析圆锯的振动与弹性稳定性

本文提出了一种分析圆锯振动及弹性稳定性的一般方法,即采用有限元法来计算特征值,这种方法考虑到了锯片几何形状,自然振动,变形以及临界转速等因素对内应力的影响。该方法分析了由于滚压和热扭曲张紧引起的形变,并计算了受临界滚压力作用时沿锯片半径方向温度差的极限值。该方法还可以应用振动频率－转速表来计算临界转速,同时考虑到锯片形状,张紧系数,热梯度等因素的作用。该方法是用于求张紧系数（转动力、转动半径）和工     

一种全新的圆锯片适张检测设备

圆锯片的适张与检测是制锯与修锯中必不可少的一道关键工序，对保证锯片稳定运转、提 高锯切精度和刀具耐用度十分重要。目前我国的相关企业，大多数还采用手工锤打适张和目 测锯片变形的“光隙法”，检测锯片的适张程度，这已远远不能适应现代工业的要求。为改 变这种落后状况，赶超世界技术发展的潮流，北京林业大学一课题组经多年努力，已成功研 制开发出一种全新的圆锯片适张状态现代计算机检测技术与设备。该技术与设备吸收了欧美 发达国家的最新相关成果，结合课题组开发的专利技术、专用软件和配套设备，可在工业环 境下对锯片状态的…     

短周期工业用材多锯片剖分过程的数学模拟研究

采用截顶椭圆一抛物面原木数学模型，应用原木的四个实测参数，测定出经多锯片裁分锯剖分的各块毛边板、板皮的精确材积；精确算出锯路的损耗和出材率。应用本文提出的理论，可以设计出简单的多锯片裁分锯数控检测系统，使短周期工业用材加工实现数控化。     

北美圆锯片张紧和整平技术—实际调整方法（续）

1 引言本文的第一部分(见本刊1993年4期)描述了锯片张紧和整平的性能及实际工作中这些性能是如何测量的。而这一部分对于调整和修整锯片的张紧和整平状态及这些技术的理论基础,加以论述并通过对实际技术的描述作出结论。用于锯片张紧和整平的方法如同用于测量这两种性能的方法一样,有许多内在的联     

小径木削片制材工艺及设备

小径木削片制材工艺及设备该成果采用自行研制的ＭＱ２８７小径木削片制方机，与剥皮机、ＭＪ３２１２跑车带踞机、ＭＪ３１１０带据机、ＭＪ１４３多锯片分锯及其他配套设备组成小径木削片制方与制材复合生产线，或与剥皮机、双轴多锯片裁分锯、单轴ＭＪ１４３多锯片裁分...     

基于动力学模型和LS-DYNA仿真的竹秆切割力研究

竹材加工工具的设计改进一般要考虑竹材和锯片的结构和性能,而其中伐竹锯片的力学特性、转速和切割过程中的振动特性是设计伐竹机械较为关键的参考因子。针对竹秆切割模型与竹秆切割时锯片和竹纤维之间产生的切割力研究,首先对圆锯片切割竹秆的过程进行动力学模型简化,抽象出实际切割系统的近似特性;进而对于竹秆切割试验的数据进行频谱分析,获得该切割过程在频域方面的特性;最后利用LS-DYNA仿真软件对切割过程进行模拟。通过参数分析,计算出竹秆切割时的锯片最佳转速约为1 155 r/min,在该转速以上工作可减少切割时产生的振动。将机械系统建模和动态分析与试验数据相结合,并将试验数据代入计算得到在切割过程中竹秆受到圆锯片的切割力约为94.38 N,LS-DYNA仿真结果显示动力学模型的计算拟合良好。该结论可为伐竹机械的设计提供参考。     

专利信息

开榫段肩木工机械本实用新型属于木工机械技术领域,其是一种开榫段肩木工机械。主要技术特征包括带工作平台的机架,在该机架上水平、垂直和斜向依次固定有三个带转轴的马达,在水平的马达上方同机架还铰链连接有第二水平马达,第一水平马达和垂直马达的转轴上分别固定有两个锯片,第二水平马达和斜向马达的转轴上分别固定有同第一水平马达相对应的锯片和斜向锯片。通过变换锯片的间距及调整第二水平马达的位置,可以完成双肩单榫、双肩双榫和斜肩单榫木工制作。解决了目前木工机械不能自动实现双肩双榫开槽工序的机械化生产问题。该机械具有结构…     

锯片的正确选择

通过下述图表可以正确地确定各种木材、木材代用品及塑料的锯割线速度、锯片直径和锯片对各种木材每分钟的切割量。操作之前要仔细分析每种锯片可能帮助延长锯片寿命,操作时能减轻对锯片的压力,这样被切割物即可得到一个光滑的加工面。如何使用图表1、可以确定锯割木材、木材代用品和塑料的线速度变化范围,由表1提示;可在图1上找出锯片直径。例如:纵向锯切针叶材,表1推荐一种线速度的范围为12000—     

数控双圆锯裁边机的研制

我国制材生产中,多采用先将原木锯解成毛边材,然后再用截边锯对毛边材进行加工的工艺。目前国内毛边材的加工设备,普遍存在结构简陋、制造精度低等不足。为提高木材出材率和板材加工精度,在分析国内外同类设备的基础上,研制出实用的数控双圆锯裁边机。     

Beiträge zur Morphologie und Biologie vonHylecoetus dermestoides L. (Col., Lymexylonidae)

Summary A contribution to the morphology and biology of Hylecoetus dermestoides L. At first the occurence ofHylecoetus dermestoides L. in the Austrian forests near Aflenz and Rosaliengebirge is described. Analyses of beech stumps are carried out. In general, beech stumps and beech stems are covered with eggs not earlier than one year after felling. The mechanical devices for timber processing such as chitin saws of the larvas and their function is throroughly described. It was found, that the chitin saws are accomodated to the steadely changing timber resistance of the canal walls due to timber decomposition byAmbrosia-mushrooms which are cultivated by the larvas.      

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     

径向槽对硬质合金圆锯片"啸声"影响的研究

"啸声"是木工硬质合金圆锯片空转的主要噪声源,是一种自激振动噪声.本文主要研究径向槽对硬质合金圆锯片噪声的影响.研究结果表明,采用金属铜填塞径向槽底部圆孔技术,可以消除硬质合金圆锯片在整个测试转速范围的"啸声".而其他两种普通径向槽的圆锯片只能在较高转速下消除"啸声".此外,径向槽底部塞有金属铜圆锯片的空气动力性噪声比未塞有金属铜的圆锯片略低2～3 dB(A).     

Development of a monitoring system for guided circular saws: an experimental investigation

ABSTRACT

Lack of a monitoring system for guided circular saws marks one of the most critical machines in sawmills as a production bottleneck. Monitoring systems are being researched and developed for machine tools, especially for the metal cutting industry; but there are limited studies on the development of monitoring systems for circular saws in wood manufacturing process. In this study, sensors with the possibility to indicate sawing deviation were chosen that could be mounted in or on the saw guides. The sensors were: a microphone, an accelerometer, temperature sensor, an acoustic emission (AE) sensor, and a newly developed displacement sensor. A load cell was used to measure the lateral force on the guides. The outputs from these sensors were compared to the standard deviation of the board surface measured at the top of the cut. The signals from the displacement sensor, microphone, accelerometer, guide force sensor, and AE senor had no correlation to changes in the sawing deviation as measured by the standard deviation at the top of the board. Under laboratory conditions, the sound level and the AE signal did indicate the beginning and end of the cut. It was found that blade temperature is a good indicator of saw cutting performance. A newly developed temperature sensor can provide accurate temperature of the saw during cutting. The sensor can be used for measuring the rate of heating to cooling over time which can be used as a monitoring system to detect if there is any issue in the system.     

Aerodynamic sound and self-excited vibration of circular saw with step thickness I: Comparison of dynamic characteristics between the common circular saw and the circular saw with step thickness

The natural frequencies, aerodynamic noise, whistling noise, and self-excited vibration between the common circular saw with uniform thickness and the circular saw with step thickness (thin on its outer part and thick on its inner part) were researched during idling. The natural frequencies of the circular saw with step thickness increased with an increase in the thickness and in the radius of the thick part. The frequencies of the circular saws with step thickness (thick at the inner part) were higher than that of the thin circular saw with a uniform thickness of 0.5mm. The aerodynamic sound pressure level induced from circular saw teeth increased with an increase in the tooth thickness. The whistling noise and self-excited vibration easily occurred in the thick circular saws (1.5, 2.0, and 2.5mm). The whistling sound pressure level and the vibration amplitude increased with an increase in the thickness of the saw. None of the designed circular saws with step thickness generated whistling noises or self-excited vibration during idling.Part of this report was presented at the 45th annual meeting of the Japan Wood Research Society at Tokyo, April 1995 and the 12th International Wood Machining Seminar at Kyoto, October 1995     

零锯料角木工锯子的初步研究

从影响锯切功率的齿距、齿槽面积以及锯料量三个因素入手，对零锯料角木工锯子的切削性能进行了研究。分析了这三个因素使零锯料角木工锯子锯切功率降低的机理，并用有关实验加以证明。其结论是，在相同的锯切条件下，零锯料角木工锯子的锯切功率小于现有传统木工锯子。     

精密裁板锯的安全问题与原因浅析

对精密裁板锯安全检测的常见问题进行了归纳及分析,旨在通过对相关安全标准条款的解读及应用来提高精密裁板锯产品的安全性能,以促进相关行业的健康发展.