-
.jpg)
Theoretical Study of the Load Distribution on the Threads for Roller Screw Mechanisms of a Friction Type(16年摩擦型滾柱絲杠螺紋載荷分布的理論研究)
t
The paper provides theoretical research of load distribution across the thread turns of the planetary roller-screw mechanism
(RSM). A characteristic feature of the theoretical approach of the paper is the use of a RSM rod model with two elastic contact
layers (the first layer is composed of screw-rollers, the second – of nut-rollers). A threaded mating of each elastic layer is
considered as a connection with continuous turns, which is closest to the truth and consistent to classical approaches. A similar
approach was applied for the ball-and-screw mechanisms with a member point contact. Thus, differential analytical closed-form
equations may be used to solve this task.
Based on the initial equation of compatibility of strains, axial offsets of contact layer points and the sum of screw, roller and nut
turn deflections are calculated; then, load distribution across the turns may be determined. Load distribution depends both on the
RSM geometry (pitch, profile angle, entry number, and thread diameter), material of threaded elements, manufacturing accuracy,
and on mating friction forces. With the dependencies of load distribution across the turns of zero-clearance RSMs obtained, we
have determined that maximum load is imposed on the outermost turns, which corresponds to classical solutions proposed by N.
E. Zhukovski.
閱讀:
2016-07-15
-
.jpg)
Static Load Distribution and Axial Stiffness in a Planetary Roller Screw Mechanism(16年行星滾柱絲杠的靜載荷分布和軸向剛度)
In this paper, an original approach is proposed to calculate the static load distribution
and the axial stiffness of a planetary roller screw (PRS) mechanism. Assuming that the
external loading is shared equally over an arbitrary number of rollers, only a sector of
the system is represented to save on computing time. The approach consists in using a
structure of bars, beams, and nonlinear springs to model the different components of the
mechanism and their interactions. This nonlinear model describes the details of the mechanism and captures the shape of the nut as well as the bending deformation of the roller.
All materials are assumed to operate in the elastic range. The load distribution and the
axial stiffness are determined in three specific configurations of the system for both compressive and tensile loads. Further, the influence of the shape of the nut is studied in the
case of the inverted PRS. The results obtained from this approach are also compared to
those computed with a three-dimensional finite-element (3D FE) model. Finally, since the
calculations appear to be very accurate, a parametric study is conducted to show the
impact of the bending of the roller on the load distribution.
閱讀:
2016-01-12
-
.jpg)
Load distribution of planetary roller screw mechanism and its improvement approach(15年行星滾柱絲杠的載荷分布)
A model of load distribution over threads of planetary roller screw mechanism (PRSM) is developed according to the
relationships of deformation compatibility and force equilibrium. In order to make the applied load of PRSM uniformly
distributed over threads, an improvement approach is proposed, in which the parameters of thread form of roller and
nut are redesigned, and the contact conditions of roller with screw and nut are changed to compensate the axial
accumulative deformation of shaft sections of screw and nut. A typical planetary roller screw mechanism is taken as
example to analyze the load distribution, and the effects of installation configurations, load conditions and thread form
parameters on load distribution are studied. Furthermore, the improvement approach is applied to the PRSM, and it is
proved to be beneficial to reach uniform load distribution over threads.
閱讀:
2015-09-01
-
.jpg)
Kinematics Analysis of the Roller Screw Based on the Accuracy of Meshing Point Calculation(15年滾柱絲杠基于嚙合點精度計算的運動學分析)
This paper investigates the meshing behavior of the roller screw, a mechanical transmission device characterized by threaded rollers
that transfer a load between the nut and the screw, by analyzing the meshing characteristics between screw and rollers. This study
seeks to establish a more accurate mathematical model for the thread surface by creating a modeling process in which the max
radiuses of the threads are calculated more precisely. The contact line distribution and the contact location were also calculated in
order to confirm the cross section of the meshing points. In the research presented in this paper, the actual transmission ratio is
analyzed and the study results in a new method to calculate the actual transmission ratio. In this study, the helical angle and the
vertex angle are proven to be of great significance after a careful analysis of their influence is conducted.
閱讀:
2015-03-25
-
.jpg)
Experimental simulation of rolling–sliding contact for application to planetary roller screw mechanism(15年滾動滑動接觸的實驗模擬及其應用)
The planetary roller screw mechanism is used in the aeronautics industry for electro-mechanical
actuators application. It transforms a rotational movement into a translation movement, and it is
designed for heavy loads. The main components are made of martensitic stainless steel, and lubricated
with grease. Like most usual rolling mechanisms, smearing and jamming can occur before the
theoretical fatigue lifetime, especially in defective lubrication conditions.
The actuated load is carried by small contacts between the threads of the screw, the rollers and the
nut. The static single contact can be described as an ellipsoid on flat contact; motion consists of rolling
with sliding perpendicular to the rolling direction. A calculation method based on elastic theories (Hertz,
Carter, Johnson) has been implemented. It calculates the normal and tangential stresses distributions,
generated in the micro-slip and stick zones of the contact area, using several input parameters such as
material properties, normal force, and creep ratio.
A specific apparatus has been developed to support these calculations and to experimentally study
the damage of the contacts in this mechanism. It consists of a freely rolling wheel loaded on a rotating
disc with a component of sliding that simulates the roller screw contact. The tribometer inputs are the
normal load, the speed, the creep ratio, and the lubrication. The wheel rolling speed and the tangential
force generated in the direction perpendicular to rolling are measured.
The experiments reveal a quick adhesive wear in dry or bad lubricated conditions, while a low
friction coefficient remains if the contact is well lubricated. The influence of the input parameters
concurs with the theoretical calculation. The evolution of grease lubrication during duty lifetime and the
influence of the tribo-chemical films on this lifetime are also studied.
閱讀:
2015-03-19
主站蜘蛛池模板:
午夜无码片在线观看影院
|
邻居少妇张开双腿让我爽一夜
|
老牛精品亚洲成av人片
|
欧美乱妇高清无乱码免费
|
我爱看片(永久免费)
|
国产在线精品区
|
成人午夜大片免费看爽爽爽
|
精品国产性色无码av网站
|
青草视频在线
|
国产肉丝袜在线观看
|
成在人线av无码免费高潮水
|
波多野结衣中文字幕2022免费
|
精品免费久久久久久成人影院
|
视频二区
|
无码少妇a片一区二区三区
无码少妇精品一区二区免费动态
|
国产精品欧美一区二区三区
|
91伊人久久大香线蕉
|
欧美综合国产精品久久丁香
|
王的女人印度剧电视剧免费观看32集
|
国产成人综合日韩精品婷婷九月
|
日韩av第一页
|
一二三四社区在线中文视频
|
中文字幕亚洲无线码
|
少妇性l交大片毛多
|
日本一区中文字幕
|
内射少妇一区27p
|
av影音|
中文字幕 国产精品
|
亚洲AV无码色情第一综合网
|
免费在线成人
|
欧美在线网
|
国产成人综合一区二区三区
|
中文字幕精品一区久久久久
|
国产精品高清一区二区三区
|
四虎最新免费网址
|
国产精品成人一区二区三区
|
国产精品久久久久久久久久红粉
|
国产福利区一区二在线观看
|
91精品国产综合久久久久久
|
无码人妻丰满熟妇区毛片18
|
成人妇女免费播放久久久
|
色中色资源
|
日日爽天天操
|
人妻另类 专区 欧美 制服
|
亚洲精品婷婷无码成人A片在线
|
国产a级一级久久毛片
|
国产一区二区三区免费
|
精品人妻无码区二区三区
|
国产av一区二区三区最新精品
|
一级做a爰片久久毛片人呢
达达兔午夜起神影院在线观看麻烦
|
成人黄色免费观看
|
亚洲第一在线
|
午夜爽爽性刺激一区二区视频
|
日韩在线高清
|
无码人妻少妇色欲av一区二区
|
免费性生活视频
|
亚洲精品国产综合一线久久
|
97福利社
|
欧美亚洲色帝国
|
少妇爆乳无码专区
|
亚洲国产片高清在线观看
|
看特级毛片
|
日韩中文字幕不卡
|
天堂av无码av一区二区三区
|
国产亚洲精品成人aa片新蒲金
|
国产精久久一区二区三区
|
中文区永久区
|
成人区精品一区二区婷婷
|
亚洲日韩欧洲无码av夜夜摸
|
欧美疯狂做受xxxxx高潮
|
男女久久久
|
天天操天天添
|
亚洲精品久久久久久下一站
|
日韩精品一区二区三区在线播放
|
日韩1区
|
高h喷水荡肉爽文np肉色学校
|
四虎成人精品一区二区免费网站
|
国产成人啪精品视频免费网站软件
|
色综合美国色农夫网
|
韩国三级午夜理伦三级三
|
邪不压正免费观看完整高清视频
|
无尺码精品产品视频
|
成人乱码一区二区三区av
|
久久久中文字幕
|
国产精品原创巨作av
|
少妇午夜啪爽嗷嗷叫视频
|
亚洲人成未满十八禁网站
|
91久操
|
亚洲欧美另类久久久精品
|
国产成人无码性教育视频
|
碰碰碰精品视频在线观看
|
久草色香蕉|
精品国产乱码久久久久久夜深人妻
|
亚洲经典三级
|
人人妻人人澡人人爽超污
|
亚州第一视频
|
日韩不卡视频在线
|
日日摸夜夜添夜夜添破第一
|
亚洲ⅴ国产v天堂a无码二区
|