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1.
Self-adjusting planetary gear rational mechanism can eliminate the influence of various uncertain errors in mechanism. Therefore ,it's method of self-adjusting designing is attented by machine designer. For seeking a simple, regular, and widely realizing self-adjusting designing way, this article uses approach of the follow text to design no over-constraint and self-adjusting mechanism. First, the article advances the conception of planetary gear structure muster and it's plotting basis, through using for reference the strategy and method of self-adjusting structure groups in planar linkage mechanism. Second, it designs the self-adjusting planetary gear structure muster, through analyzing the constraint and freedom of planetary gear structure muster. Third, it designs the self-adjusting mechanism, through adding aptitude rotational links outside of self-adjusting planetary gear structure muster. This mechanism can realizes the self-adjusting in the interior of muster and self-adapting in the exterior of muster. This designing plan possesses a series of excellence, such as, theoretical, simple, feasible, widely self-adjusting. Consequently, the mechanism can eliminate the working capability influence of various errors.  相似文献   

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不同配方复合肥对籼粳杂交稻化肥减量增效的探索   总被引:1,自引:1,他引:0  
为了解不同水稻配方复合肥在籼粳杂交稻(‘甬优12’)上的化肥减量增效效果,选择当地常用的4种水稻配方复合肥,以常规施肥为对照,在化肥总养分均减少10.2%的条件下,探索其对水稻的节本增效。结果表明:综合水稻生育表现、经济性状及产量,施用水稻配方专用肥(16-10-14),水稻生育表现佳,化肥成本减少16.90%,增产1.76%,对水稻化肥减量增效效果最好,适合在当地进行推广应用;施用复合肥(20-12-14),水稻综合表现次之,节本增效效果不显著;施用复合肥(22-6-12),水稻综合表现较差,节约的肥料成本不抵减产产值;施用复合肥(15-10-17),水稻综合表现最差,肥料成本上升,产量也下降。  相似文献   

4.
梁龙  孙凯  张昌柱 《中国农学通报》2022,38(20):149-155
为探明贵州省调减玉米种植后改种辣椒经济作物的生态效益,本研究以锦屏县为例,基于对80个小农户及4家合作社的调查数据,采用生命周期评价法,对该地区辣椒生产的能量流和碳足迹进行定量评价。结果表明:(1)辣椒生产的能量输入为53431.8 MJ,远大于产出的9000 MJ,净能量效益为-44431.8 MJ;其中,化肥和农膜占有能量投入的最大比重,分别是53%和16%;能量利用效率、单位产品能量比和单位能量生产率分别为0.17、4.75 MJ/kg和0.21 kg/MJ;(2)碳足迹结果为碳排放大于碳固定分别是5450.9 kg CO2eq和2227.3 kg CO2eq;净碳效率(0.41)小于1,属温室气体排放贡献源;化肥生产运输环节和农作肥料施用环节对农田碳排的贡献最大分别为44.7%和32.07%;有机耗碳比、单位面积碳足迹、单位产品碳足迹和单位经济效益碳足迹分别为0.07、0.55 kg CO2eq/m2、0.48 kg CO2eq/kg、2.91元/kg CO2eq。可见,在该地区,产业结构调整后辣椒种植存在潜在的生态风险。因此,优化农资投入结构,减少化肥施用,增加有机质投入占比,发展清洁能源,加强良种选育是今后锦屏县域辣椒生产提能效、减碳排,实现生产与生态共赢的关键。  相似文献   

5.
After self-dissolvable nickel-base alloy spray-welded on the surface of scrapped gear of which 40CrNi is base metal is obtained. Using non-coating lengthen hob,moving the hob in axial,aligning the hob and adopting suitable cutting conditions,the better methods of hopbbing spray-welding gear profile are found out.  相似文献   

6.
江西省从2009年起开展“籼改粳”引种、示范和推广,至2016年粳稻种植达到一定规模。2015年,农业部在全国部署开展化肥使用量零增长行动,推动化肥减量增效。为探索粳稻化肥减量增效施用技术,并助推“早籼-晚粳”种植模式,于2016年在浮梁县开展了晚粳化肥减量增效施用方法的比较试验。试验设空白对照、农户习惯施肥方法和2种推荐施肥方法4个处理。推荐施肥方法为化肥减量配方施肥。试验结果显示,2种推荐施肥方法中以推荐施肥方法1较好,推荐施肥方法1比农户习惯施肥方法氮磷钾养分总量节省123.9 kg/hm2、稻谷增产608.75 kg/hm2、增加净收入2070.35元/hm2,经济效益达到了显著水平。推荐施肥方法 1的总偏生产力为13.34、投产比值为6.39,比农户习惯施肥方法分别增38.4%和36.54%。试验表明,推荐施肥方法较农户习惯施肥方法具有明显的节肥增产增收效果,可在当地双季晚粳化肥减量增效生产中推广应用并加以完善。  相似文献   

7.
水稻生产过程中化肥的不合理施用,带来了农产品生产成本增高、农田环境污染等问题,影响水稻生产的可持续发展。于2018—2020年,在单项技术研究基础上,开展本研究,旨在形成适合华南双季稻区的化肥减施增效综合技术模式。研究选用高产、高效水稻品种(双高),同时优化氮、磷、钾肥的比例结构以及基蘖肥的比例结构(双优),在化肥中补充施入海藻精和微生物菌剂(双补),合理平衡移栽密度与肥料施用量、水气平衡方法水分管理(双平衡)的方法。2019—2020年在象州和宾阳县进行技术示范,化肥减量综合技术示范区的化肥施用量比对照减少化肥用量17%(包括氮、磷、钾肥)基础上,平均稻谷产量分别为6479.76 kg/hm2、6755.62 kg/hm2,其稻谷产量分别比对照增产2.30%和6.55%。本研究总结了华南双季稻化肥减施增效技术规程。  相似文献   

8.
This article summeried the methtods in finish machining of hardened gear and mainly introduced the development of the form grinding technique in grinding wheel dressing and grinding technology. The technique, which makes use of CBN tools, of hardened gear finish machining is also briefed.  相似文献   

9.
Considering that the transmission system of wind turbine works in complex and changing load environment caused by stochastic wind speed,this paper uses sparse least squares support vector machine(SL-SVM) to simulate wind speed of true wind field,and obtains time-varying wind load caused by stochastic wind speed. The lumped-parameter method is used to develop a dynamic model of planetary gear transmission system of wind turbine coupled with bearing. The model includes the varying wind load,time-vary mesh stiffness of gear pair and time-vary stiffness of rolling element bearing. The numerical method is used to simulate the dynamic performance of planetary gear system of Multibrid Technology Wind Turbine with 1.5 MW rated power. The vibration displacement responses of the transmission system are obtained as well as dynamic meshing force each pair of gear and nonlinear bearing forces. The research can provide a foundation for optimizing dynamic performance and reliable design of gear transmission system of wind generator.  相似文献   

10.
Based on the infroduction of the present process of quenched internal gear, a new technolgy of machining quenched internal gear-EDM generating technology is presented with its principle and machining processes. .  相似文献   

11.
The study of motorcycle's acoustic signal shows that gears noise take a great proportion on the whole acoustic of motorcycle.So how to control the noiseof gears is very helpful for reducing the whole motor's acoustic.This paper discusses the engine matching with transmission system in reason,primary transmission and gear geometry design parameter & the mend of tooth body(tooth form & tooth direction) how to influence the acoustic of motorcycle.The study shows that the gear transmission System's matching with engine in reason can notable improve the efficiency of motorcycle.In the meaning time the exactly choosing the primary transmission gear geometry design parameter and the mend of primary transmission gear's tooth body can effectively reduce the acoustic of motorcycle.This paper has engineering practice sense.  相似文献   

12.
To research the mechanical and influence factors of noise of valve train of engine, noise-distinguishing test is taken with one certain 125 mL engine valve train. The result reveals that the valve train noise mainly results from impacting between rocker and valve stick, impacting of valve seating. With the way of model set up and simulating calculation of kinematics and dynamic of valve train, the influence factor of rocker impact force and valve seating acceleration of valve train is studied, which reveals that the acceleration of valve and impacting force between rocker and valve stick are mainly relied on cam buffer segment lift, cam buffer segment wrap angle and coefficient of accelerating segment of cam buffer segment. Choosing these parameters reasonably is helpful to decrease the acceleration of valve and impacting force between rocker and valve stick, and then reduce the noise of valve train.  相似文献   

13.
The analysis of the existing way and amount of profile modification of cycloidal gears at present showed that the equidistance and movedistance modification is in substance really to have the profile swelled up,and the rational modification way and amount is a swelling correction within the range of zero to some limit. This paper presents a new modifying way which is optimum compound modification at separate parts. The modified profile has the most simultaneously transmission teeth,even side clearance and the longest wear-life to forming crush dressing roll and is also easyly to NC machining.  相似文献   

14.
On the basis of studying shield machine and planetary transmission, to address cutting drive system of shield machine, a novel dual drive planetary transmission system with large capacity is presented, and its principle and structure are analyzed. Through establishing a new kinematical model of the transmission system and analyzing its characteristics, the transmission ratio, rev and torque relationship and changing rules within the system are acquired. By comparing the simplified experimental results with theoretical results,it is shown that the variation is basically the same, which verifies the correctness of the model and analysis method. The high-power dual-driven planetary gear transmission system with great transmission ratio, strong carrying capacity, can perform the function of low-speed and high-torque output, and meet basic requirements of shield machine. It can not only replace the traditional multi-driven transmission system, but also achieve the transmission function in three different types of shield machine.  相似文献   

15.
以变位圆柱齿轮几何尺寸的计算为例,阐述了利用中文Excel函数替代机械设计时大量手工计算的方法。只要根据使用条件在相应的单元格内输入常量,系统会自动生成齿轮的几何尺寸。该方法适用于机械设计需要计算的诸多方面。  相似文献   

16.
In this paper, the mathematical model for gear planing of precise and hardened gear is established. The computational charts and results for the tooth edge height,cutter edge contact length and cutter area are given out to improve the present planing technique.  相似文献   

17.
The paper analysed the influence of x gear on the movement law of each engaging point and the flow characteristic of the second kind of compound gear pump with x gear.The formula of flowrate and flow pulse are given with the best type of instruction.  相似文献   

18.
In order to reduce quench deformed of car gear, a new kind of microdistortion gear steel is developed and its fine microstructure is discussed by SEM. The results show that the tested steel can obtain carbide free bainitic ferritic laths with fine microstructure under air-cooling condition. The bainitic ferritic laths, sublaths and subunits are surrounded by retained austenite, which can insure the gear steel possesses high strength and toughness, the impact toughness has increased remarkably. The good mechanical performance of the steel can meet the service demands of the gear.  相似文献   

19.
The stiffness of the tooth with different profile parameters,meshing stiffness and the coefficients of loading distribution allowing for no error are calculated and analyzed on double involute gear with ladder shape teeth for the first time,and the results are made comparison with traditional involute gear;The stiffness of the double involute gear and the meshing stiffness are both increased,and the coefficients of loading distribution are basically unchanged.The energy integration method is also put forth to solve stiffness approximately by linear approximating the tooth profile curve.  相似文献   

20.
This paper introduces phenomenon of electric erosion of gear and the research condition and evolution of it; puts forward a point of view that a system of electric erosion of gear is a especial tribology system which is in relation to many subjects and in which many phenomena exist and coupling each other , moreover , it is very difficult and complex to study electric erosion of gear by experiment ; have made statistical datas about typical example of electric erosion of gear inland ,at this base ,summarizes characters of electric erosion of gear and the study means of it.  相似文献   

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