Excite Timing Drive 基础培训-液压链条张紧器

Working Volume
po Leakage Gap
po Ventilation
Retainer Spring
Check Valve ξ = ξ(Re)
Supply psupply
Mechanic Component
Moving parts: Ball Plunger
Stops: Ball’s Seat Cage
1st Volume
100% Flow rate
2nd Volume
Momentum Flow Unit
Contributing flow for 2nd Momentum unit
Contributing flow for 1st Momentum unit
1
2
Principle of application
A1, ρ1
v2 A2, ρ2
Density of the fluid in the SECOND connected volume
Connected Mass element
Link Point on Connedcted Mass
F
Density of the fluid in FIRST volume
Maximum roughness height
Laminar to turbulent flow transition Additional resistances
Minimum roughness height
Average roughness height = Wall roughness
end
Flow rate from connected Hydraulic Connection with contribution assigned to the Momentum flow unit
Pressure taken from the SECOND connected volume
粘压系数
随压力变化的压缩模量
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计算润滑油的动力特性
8
通用液压单元
Generic Hydraulic Elements
Hydraulic Volume - DOFs and Properties
Chamber Volume
Fluid Volume
Gas Volume
Fluid pressure equals to zero until Gas Volume is consumed
Connected Body
Body motion
F - Force on body Fm - Force in direction of body motion
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连接模型
1维或2维 质量单元－液力容积
坐标系
连接类型 柱塞
1维或2维
横截面积
运动矢量方向 力的矢量方向
流动 横截面积
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液压机构连接 Hydromechanic Connection
Throttle & Valve Flow Unit
Flow area Hydraulic Diameter * π * Lift
Hydraulic Diameter
Ball Valve
Disk Valve
Lift
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连接模型
节流阀 连接类型
节流阀 有效流动面积，随…变化
运动自由度
流体特性表 给定有效流动面积 可变/常数
Springs: Valve Spring Retainer Spring
Model
rigid body rigid body
spring-damper unit spring-damper unit with lash
pre-loaded spring-damper unit pre-loaded spring-damper unit
Pressure explicitly prescribed
p
p
const.
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液压连接 Hydraulic Connection
Line Flow Unit
1st Volume
Length
Line
2nd Volume
Hydraulic Diameter
Wall roughness
Surface in contact with fluid
Volumes
定义容腔之间的相互作用(流量) Defines
interaction between volumes (flow rate)
可用于三种流动单元 Three FLOW UNITS: 管道流动 Line 节流阀流动 Throttle & Valve 泄漏 Leakage
5
Hydraulic Elements
液压机械连接-两种方式
1st type 连接容腔和质点单元 传递受力和压力 两种流动方式: 柱塞式 容腔体积/压力的变化
2nd type 液压连接和质点之间的连接 定义动量流动的部件
6
通用液压单元
连接模型
流体特性表 Fluid Properties and Compressibility
密度 动力粘度
液体容腔 液压连接 – 容腔间的连接关系 液压机械连接 – 容腔和质点之间的连接关系
3
通用液压单元
Generic Hydraulic Elements
液压容腔Hydraulic Volume
3自由度Three (3) DOFs: 压力 Pressure 液体容腔 Fluid Volume 气体容腔 Gas Volume
from the chain to the structure
由于较高的阻尼导致高频范围隔
振不良Poor isolation in high frequency range
due to high damping ⇒ chain whine excitation
为调整链驱动动力学特性的唯一
可变动的零件Usually the only component
试验条件：柱塞简谐激励：振幅+/-0.2mm 频率30/100/200 Hz
Test rig conditions: harmonic excitation of plunger +/- 0.2 mm @ 30/100/200 Hz
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液压张紧器 Hydraulic Tensioner
张紧器台架试验 Tensioner Rig Test
2nd Volume
10
连接模型
管道流动
管道长度 管道内表面粗糙度 管道直径
连接：容积1－容积2
泄漏
机油特性 随压力变化的压缩模量 外径 内径
定常/变化间隙 半径间隙
间隙长度 连接：工作容积－链条套管接头
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液压连接 Hydraulic Connection
Leakage Flow Unit
Ring Gap
to be changed in order to improve chain drive dynamics: dilemma of “fixed” chain drive layouts at late design stages
液压单元
正时系统中的液压单元
液压挺柱 液压张紧器 液压间隙调节器
液压系统包括:
Volume to Mass element
将压力转成总力 Transforms pressure to force 用于两种单元 Two flow units can be defined:
柱塞 Plunger 变化或流动容积 Volume Change/Flow
类型2 2nd type 连接液力连接与质量单元 Connects Hydraulic
可使用所有自由度 All DOFs are always enabled
供油腔 调入：流体特性表 标准液力容积
预定压力 定常或可变的数据表
工作腔 初始容积 初始压力
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液压连接 Hydraulic Connection
液力连接 Hydraulic Connection
两个液力容腔的连接 Connects two Hydraulic
1 - First Momentum flow unit 2 - Second Momentum flow unit
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连接模型
1维或2维
质量单元－液力容积 坐标系
第一和第二端点的流动矢量方向
连接类型
横截面积
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液压张紧器 Hydraulic Tensioner
张紧器工作循环压力特性 Characteristics of different Tensioner Types
简谐运动激励：+/-0.2 mm at 30 Hz等频率
Harmonic Motion Excitation
力响应
Force Feedback
Pressure [bar]
测试
Measurement
模拟
Simulation
Time [s]
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液压张紧器 Hydraulic Tensioner
Model
Connection to Mass element
用于动力流动单元 One or two Momentum Flow
Units can be defined
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液压机构连接 Hydromechanic Connection
Plunger Flow Unit
Volume
Pressure, Flow rate
textFm
F
Plunger
Plunger motion
F - Force on plunger Fm - Force in direction of plunger motion
Volume Change/Flow Flow Unit
Volume
Pressure Prescribed Flow
textFm F
Pressure taken from the FIRST connected volume
p2 2
Flow direction at first end
1
v1 p1
Flow rate from connected Hydraulic Connection
with contribution assigned to the first Momentum flow unit
ADVANCED SIMULATION TECHNOLOGIES
基础培训
液压链条张紧器
ADVANCED SIMULATION TECHNOLOGIES
张紧器：升压和泄
压特性对皮带啮合跳
动和啮合力的影响
Dynamic Meshing Behaviour of Tensioner: Check & Relieve Valve (Belt: Mating disturbances, Tooth Climbing) and Contact Forces
Pressure defined with flows
flow
p
flow
Gas Volume (positive)
Gas Volume (negative)
Chamber Volume Fluid Volume
Chamber Volume p>0 p=0
Fluid Volume
Chamber Volume=Fluid Volume+Gas Volume
Outer ring diameter
Inner ring diameter
Gap Height
Gap Length
p1
p2
text
Body
Ring gap
Plane Gap
Gap Width
Plane gap
Gap Height
Gap Length
p1
p2
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液压连接 Hydraulic Connection
液压链条张紧器
hydraulic Chain Tensioner
补偿磨损造成的链伸长Compensation
of chain elongation (wear)
提供预紧力和阻尼Provides pre-tension
and initiates damping
传递链到机体的力Transmits forces
节流阀
保持弹簧
物理模型
泄油
工作容积
简化模型
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液压张紧器 Hydraulic Tensioner
工作容积
保持弹簧
节流阀
泄油
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液压张紧器 Hydraulic Tensioner
Results
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液压张紧器 Hydraulic Tensioner
po
ReliefValve ξ = ξ(Re)
Plunger
随位移或时间变化 阻阀簧 平移或旋转自由度
数据调整因子
流阻，常＝10
连接：机油供给－工作容积
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液压机构连接 Hydromechanic Connection
液力机械连接 Hydromechanic Connection - 2 types
类型1 1st type 连接液力容腔与质量单元 Connects Hydraulic