-
.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：
国产午夜在线观看
|
日韩一级电影网站
|
欧美影院久久
|
久久久久亚洲国产精品
|
久久婷婷一区二区三区
|
色99网
|
欧美特一级片
|
天天操天天操天天操
|
国产精品v a免费视频
|
国产精品久久久久9999吃药
|
中文字幕在线观看日本
|
国产视频一区二区在线
|
天天综合视频在线观看
|
亚洲精品福利在线观看
|
天天操天天吃
|
国产高清综合
|
99精品视频精品精品视频
|
欧美精品一区二区三区四区在线
|
五月激情亚洲
|
午夜精品久久久久久久99水蜜桃
|
a√资源在线
|
亚洲精品动漫成人3d无尽在线
|
色中射
|
伊人va|
韩国精品一区二区三区六区色诱
|
久久精品在线视频
|
婷婷久久国产
|
麻豆一区二区
|
日日操网站
|
午夜电影 电影
|
久久精品超碰
|
国产尤物在线视频
|
欧美大片大全
|
日韩免费中文
|
国产精品一区二区三区电影
|
六月婷婷网|
国内精品免费
|
中文字幕日韩电影
|
日韩女同一区二区三区在线观看
|
永久免费的啪啪网站免费观看浪潮
|
成人黄色电影在线
|
91av超碰
|
a在线观看视频
|
毛片网站观看
|
国产1级视频
|
九九免费观看视频
|
久久免费视频3
|
四虎在线观看精品视频
|
久久久精品国产一区二区
|
黄色三级免费片
|
久久99久久99|
狂野欧美激情性xxxx欧美
|
日韩精品视频第一页
|
中文字幕视频播放
|
日韩在线电影一区
|
日日夜夜精品视频天天综合网
|
国产精品aⅴ
|
中文字幕在线视频网站
|
激情在线网站
|
日韩三区在线观看
|
欧美三级高清
|
深爱激情婷婷网
|
久久综合桃花
|
国产亚洲精品成人av久久ww
|
五月婷婷综合久久
|
国产玖玖在线
|
综合色站导航
|
久久久免费国产
|
久久久久久久久久久久99
|
午夜色站
|
91探花在线|
久久久久久久久久福利
|
久久精品美女
|
精壮的侍卫呻吟h
|
精品一区二区在线免费观看
|
日韩一级电影在线观看
|
亚洲欧美日韩一二三区
|
久久这里只有精品首页
|
特黄特色特刺激视频免费播放
|
国产精品高清在线
|
日韩av免费一区
|
91精品久久久久久粉嫩
|
91在线免费观看网站
|
精品国产乱子伦一区二区
|
久久伦理电影网
|
在线观看亚洲电影
|
av片一区二区
|
久久久久久久网
|
av观看在线观看
|
国产特级毛片aaaaaa毛片
|
www色片|
欧美精品在线免费
|
成人久久久久久久久久
|
国产高清不卡
|
精品亚洲免费
|
日韩精品一区二区三区中文字幕
|
视频在线一区二区三区
|
国产精品成人久久久久久久
|
9免费视频
|
