排序方式： 共有11条查询结果，搜索用时 375 毫秒
1.
裴碧峰 《福建工程学院学报》2005,3(1):66-70
深入分析了“顺穿法”和“花穿法”绕制的单行并联式滑车组在起重工作时的受力性能，通过对滑车组的偏心距和倾斜角计算，证明偏心距及倾斜角较大时对滑车组的工作和使用寿命存在很不利的影响。详细分析了混联式滑车的构造和受力性能，并对其起重时的偏心及倾斜角进行了计算，计算结果表明该新型滑车组在构造和技术上具有明显的优越性。混联式滑车于1996年获得国家发明专利。 相似文献
2.
蔡厚贵 《贵阳学院学报(自然科学版)》2011,6(3):13-17
在滑轮问题中,绳的张力并没有直接作用在滑轮上。分析定滑轮和动滑轮的转动,发现绳的张力是通过转化为摩擦力矩或支承力矩间接起作用的。并且在滑轮的转动中。摩擦力矩总是在发挥着作用。 相似文献
3.
皮带轮是一种重要的机械传动零件,它广泛应用于汽车、农机及轻纺工业等各种机械设备的传动中。皮带轮传统生产方法是采用锻、铸造毛坯经切削加工而成,其缺点是浪费材料,生产率低、产品精度低。旋压技术是一种先进的成形工艺,运用这种技术生产的皮带轮,具有传动平稳、精度高、节材、生产效率高、环保、使用寿命长等优点。本文以浙江东星汽车部件有限公司的产品为研究对象介绍多楔旋压皮带轮。 相似文献
4.
鲍俊瑶 《安徽职业技术学院学报》2012,(1):1-4
电动滚筒是近年来出现的新型带式输送设备的驱动部件,具有适宜在恶劣场合工作的能力。然而,电动滚筒的噪声却带来污染,并在高要求场合应用受到限制,为此必须降低其噪声。在对电动滚筒可能存在的主要噪声源进行分析的基础上,应用频谱识别技术,确定了单相驱动电机是该型电动滚筒的主要噪声源,它使得电动滚筒在100Hz及其高次谐频噪声成分较大。经分析,造成此现象的原因是单相驱动电机的空间不对称驱动力矩,在采用三相电机驱动后,电动滚筒的噪声下降了6～7dB(A)左右,有效地控制了电动滚筒的电磁噪声。 相似文献
5.
介绍了可开合式双头滑车的研制过程,阐述了该装置在线路带电作业、等电位作业等工作中的实际使用情况.通过对该装置和现有的双头滑车在工作中的使用情况进行对比发现,该装置设计合理,操作方便,完全解决了现有双头滑车从导线上脱落的问题,提高了工作效率和安全性,在实际工作中具有可行性. 相似文献
6.
蔡厚贵 《贵阳金筑大学学报》2011,(3):13-17
在滑轮问题中,绳的张力并没有直接作用在滑轮上。分析定滑轮和动滑轮的转动,发现绳的张力是通过转化为摩擦力矩或支承力矩间接起作用的。并且在滑轮的转动中。摩擦力矩总是在发挥着作用。 相似文献
7.
王寿槐 《沙洋师范高等专科学校学报》2006,7(5):74-77
本文针对刚体转动惯量实验仪的不足，提出了改进方案，使仪器功能更强大，实验操作更简捷，误差更小，成功率大大提高。 相似文献
8.
《European Journal of Sport Science》2013,13(8):696-702
AbstractThis study investigates the changes of the connective tissue in the fingers of performance sport climbers resulting after a minimum of 15 years of climbing. Evaluation was performed by ultrasonography on the palmar side of the fingers (Dig) II–V to measure the thickness of the A2 and A4 annular pulleys, the flexor digitorum superficialis (FDS) and profundus (FDP) tendons and the palmar plates (PP's) of the proximal interphalangeal (PIP) as well as distal interphalangeal (DIP) joint in sagittal and axial direction. Totally, 31 experienced male sport climbers (mean age 37y, 30–48y grade French scale median 8b, range 7b+ to 9a+) participated in the study. The control-group consisted of 20 male non-climbers (age 37y, 30–51y). The A2 and A4 pulleys in climbers were all significantly thicker (A2 Dig III 62%, Dig IV 69%; A4 Dig III 69%, Dig IV 76%) as compared to non-climbers pulleys. All PP's of the DIP joints were also significantly thicker, particularly at Dig III and IV (76 and 67%), whereas the PP's at PIP joints were only scarce significant for three joints. Differences of the diameter of the flexor tendons were less distinct (1–21%) being significant only over the middle phalanx. High load to the fingers of rock climbers after a minimum of 15 years of climbing years induced considerable connective tissue adaptions in the fingers, most distinct at the flexor tendon pulleys and joint capsule (PP) of the DIP joints and well detectable by ultrasound. 相似文献
9.
港口移动式高架起重机是一种在轮胎式起重机基础上发展起来的港口多用途起重设备,其变幅系统优化设计是方案设计的关键。为此,建立了变幅系统的力学模型,利用Matlab/GUI的设计和编程功能,开发了高架起重机变幅系统计算软件,实现了高架起重机重物运动轨迹、起重性能和变幅油缸的设计计算。在此基础上,对YHC280型高架起重机变幅系统进行了优化仿真实验,得到了塔柱滑轮组坐标和变幅油缸铰点坐标变化对变幅系统性能指标的影响,确定了满足变幅系统各项性能指标的设计参数,为港口移动式高架起重机变幅系统设计提供了参考。 相似文献
10.
Ben D. Mahaffey 《The Journal of environmental education》2013,44(4):30-31
Abstract The authors examined environmental concern and involvement of individuals in two voluntary associations, the International Mountain Bicycling Association (IMBA) and National Off-Highway Vehicle Conservation Council, Inc. (NOHVCC). Environmental concerns were assessed using the New Environmental Paradigm (NEP). When compared, results from 10 of 12 NEP items were found to be significantly different. The IMBA group scored higher on the NEP, showing a greater level of agreement on environmental concern. IMBA respondents were also more involved with environmental organizations than the NOHVCC sample. The study results suggest that the level of environmental concern and involvement differs for those who are in specific voluntary associations and who choose specific outdoor activities. Implications are discussed for educators and resource managers. 相似文献