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摇台摆角是弧齿锥齿轮加工机床设计的重要参数之一,它的大小关系到能否切出工件的全齿长,正确合理的计算弧齿锥齿轮切齿机摇台摆角,是保证齿面质量的关键问题,鉴于摇台摆角θ是分齿数z1的函数,就弧齿锥齿轮切齿机床摇台摆角的计算方法展开了讨论,合理解决了摇台摆角调整参数的通用性计算问题,列举了计算实例,表明了采用的计算方法简单实用且效果好。 相似文献
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详细介绍了双重收缩直齿锥齿轮的几何计算过程,根据双重收缩直齿锥齿轮的特点总结了一套铣削加工的方法。该方法可减少刀具修形,提高齿轮啮合精度。 相似文献
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通过对滚齿加工中滚刀安装角的分析,提出用标准滚刀滚切标准齿轮、短齿圆柱齿轮及变位齿轮时滚刀安装角的公式,并分析了滚刀安装角误差对被加工齿轮齿形精度的影响。 相似文献
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为了提高齿轮齿距螺积误差和齿距偏差的数据处理速度和精度,采用BASIC语言编制了程序,并在计算机上进行了实际运算。 相似文献
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设计计算正交直齿圆锥齿轮传动时,对于闭式传动,应先按齿面接触强度初步确定主要尺寸,然后进行接触疲劳强度和弯曲疲劳强度的校核。根据目前设计计算中普遍采用的《机械设计手册》,中册(化学工业出版社、第二版,以下简称《手册》)第八篇第五章推荐的正交 相似文献
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齿轮轮齿的加工,通常用滚齿或插齿,现将其径向进刀量(即切削深度)△t的确定作一叙述。一、滚齿加工滚齿加工时,滚刀的径向进刀量(即切削深度)△t理论上是等于全齿高h=2.25m。但由于齿坯外圆的精度及滚刀刀齿齿厚的变化, 相似文献
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水利启闭机常用到大模数渐开线齿轮传动,其齿轮加工一般用指形铣刀铣齿法。分析了渐开线齿轮齿根过渡曲线,以求得指形铣齿法的最佳齿根过渡曲线。 相似文献
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Daniel O. Okeyo 《Lakes & Reservoirs: Research and Management》2014,19(3):192-205
This study focused on providing a photodiagrammatic database illustrating various types of fishing gear and practical skills currently used in artisanal and commercial fishing in the shoreline, nearshore and offshore areas drainage systems of Kenya in the Lake Victoria drainage basin. It also identified the fish species typically caught by the fishing gear, and the gear catch per unit effort and selectivity. Four artisanal fishing gears (spear, trap, basket and hook) and two commercial gears (mosquito seine and purse seine) are used to fish in shoreline areas. Five commercial fishing gears (gill net, parallel tennis net, semicircular‐tennis net, sett net, long line) are used to fish in nearshore areas, while two commercial gears (drift net and offshore seine net) are used in offshore areas. For artisanal fishing, the basket is the most efficient gear for catching six fish species. The mosquito seine is the most efficient commercial fishing gear for catching 22 fish species. There is evidence for a chronological shift to more efficient artisanal and commercial fisher handmade fishing gear, resulting in overexploitation of diverse fish species. At the same time, the licensing and management policies for the use of various fishing gear are unclear, suggesting re‐evaluation of policies to cater for the use of handmade fishing gear. 相似文献
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常规齿轮减速器优化设计中忽略了可靠性指标,使设计不够理想。通过实例阐述了齿轮强度可靠性约束条件的引入方法,并运用相关数学理论和优化设计方法建立了二级斜齿圆柱齿轮减速器可靠性优化设计数学模型。 相似文献
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郑州某热电厂200MW机组磨煤机的减速机配置了自润滑油泵及润滑油冷却器形成的润滑油系统,运行中因减速机自润滑油系统运行不稳定,频繁造成减速机损坏。对#2机组4台磨煤机减速机润滑油系统进行了优化改进,采用磨煤机大瓦润滑油站供油,为减速机提供润滑与冷却,#2机组磨煤机减速机运行可靠性大幅提高,可为使用同类型磨煤机减速机的电厂提供参考。 相似文献
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Elsayed A. Khallaf 《河流研究与利用》1988,2(4):547-552
Changes of faunistic composition in impounded reaches of regulated rivers have been related to changes in environment from lotic to lentic. Rarely has this assumption been tested, however, Bagrus docmac is a long-lived freshwater catfish and was once a commercially valuable species in Lake Nasser. Its production declined abruptly following the early years of impoundment of the lake. This decline is significantly correlated to the increase of Tilapia catch. A modified model for the surplus production is introduced and estimated the potential yield as 195·7 metric tonnes. Relative growth rate of weight over length interval showed that the fish ranging between 20 to 40 cm in standard length have had the highest rate of weight gain which is attributed to gear selective mortality. Fish (18-83 cm in standard length) vertebrae (N = 105) are used for growth analysis, after their annuli are validated. Age-groups ranged between I to VI with an average age of 3·14. Age-groups II suffered high selective mortality which caused a fishing-up effect that took about four years to appear in the catch. Thus, the problem of Bagrus may be safely attributed to the effect of fishing gears which are mainly used to catch the relatively smaller Tilapia. 相似文献
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滚圆在导圆内周的内摆线运动轨迹,在特殊几何条件下会蜕变为通过导圆中心的直线,将齿圈分度圆作为导圆,行星齿轮分度圆作为滚圆并使2个分度圆直径满足1倍比关系。设计制造出行星齿轮无级调速器,通过对其进行运动分析和工作性能测试,验证了该装置可实现无级调速。 相似文献
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刘锡鸣 《中国水能及电气化》2020,(3):20-25
水轮发电机组盘车质量的好坏直接决定机组的检修质量,影响着机组运行的安全性和稳定性。文章以白石水电站1号机组盘车过程为例,详细论述了盘车数据分析和机组轴线调整方法,特别是0轴绘图法的创新应用。效果表明:该方法易于理解、便于掌握,可为类似立式水轮发电机组的盘车提供指导和借鉴,对提高盘车质量和检修效率起到促进作用。 相似文献
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"长江重件1号"滚装船襟翼舵的安装难度较大,其大齿轮与下舵承本体的焊接只能在现场进行全位置施焊,为保证在焊接后大齿轮与小齿轮的啮合性良好,因此对装配工件的工艺性进行分析和工况焊接模拟实验,该工艺成功地应用于现场装配后的焊接,有效地控制了焊接变形,保证了襟翼舵的安装质量。 相似文献