Switching Nip Roller
Switching nip roller component
Description
Usage
Equations
Connections
Parameters
Summary Variables
The Switching Nip Roller component models a pair of rollers: a nip and a roller. It differs from the Nip Roller component in that it allows for the upstream/downstream spans to switch between the two rollers during the simulation.
The Switching Nip Roller component must be between two Span components.
The Switching Nip Roller pulls the web without of slippage using 1D rotational flange flangec1 or flangec2 under torque or velocity control.
The Switching Nip Roller is similar to the Roller component; the main difference is the added inertia and bearing friction from two rollers.
Consider the two rollers shown below.
Assume the web velocity goes through a discontinuous velocity change at the b (right) boundary.
Ta, Tb
Upstream and downstream tensions, respectively
va, vb
Upstream and downstream web speeds, respectively
τ1,τ2
Motor torque applied to roller 1, 2
R1,R2
Roller 1 and 2 effective radii
ω1,ω2
Roller angular velocity
J1,J2
Moment of inertia of roller 1 and 2
b
Bearing damping coefficient
W
Web width
β
Wrap angle
Under no-slip assumption (for all configurations), we have:
va=vb=R1⁢ω1=R2⁢ω2
and
J1R1⁢dω1dt+J2R2⁢dω2dt+b⁢ω1R1+ω2R2={τ1R1−Ta+TbSide=1τ2R2−Ta+TbSide=2
Name
Modelica ID
framea
Left web 3-D connection point
frame_a
frameb
Right web 3-D connection point
frame_b
framec
Roller holder base frame; enabled when Use fixed base=false
frame_c
weba
Left (entry) web transfer information port (blue)
web_a
webb
Right (exit) web transfer information port (green)
web_b
flangec1
Roller rotation flange; enabled when Side=1
flange_c1
flangec2
Roller rotation flange; enabled when Side=2
flange_c2
Web Properties
Default
Units
Use Default Properties (WP1)
true
When checked (true), web properties are defined by the closest Web Properties block found
useDefault
WP1
Name of the record containing the web properties (enabled when Use default properties = false)
wp
Settings
Use alternative configuration
false
Choose between two possible solutions for the web/roll configuration
useAltConfig
Flip direction
Use this option when building web lines that go from right to left.
flipDirection
Use fixed base
When checked (true), frame is fixed in the inertial coordinate frame
useFixedBase
r
0,0
m
Location of frame_b with respect to ground. Available when Use fixed base = true
InitPos
θ
0
deg
Rotation about z-axis. Available when Use fixed base = true
InitAng
Roller
D1
0.2
Diameter of roller 1
Di1
Inner diameter of roller 1
D2
Diameter of roller 2
Di2
Inner diameter of roller 2
L
1.2
Roller length
Use cylindrical geometry
When checked (true), roller inertia is calculated assuming a uniform cylindrical geometry
useCylindricalGeometry
ρ
2.7·103
kgm3
Roller density; enabled when using cylindrical geometry
rho_roll
m1
1
kg
Roller 1 mass; enabled when not using cylindrical geometry
m2
Roller 2 mass; enabled when not using cylindrical geometry
J1
0.005
kg⁢m2
Roller 1 rotational inertia; enabled when not using cylindrical geometry
J2
Roller 2 rotational inertia; enabled when not using cylindrical geometry
d
N⁢m⁢srad
Bearing viscous damping constant (both rollers)
Frame
Reference frame
Middle of the gap
Select option for the location of the framec (holder). There are three options available: Middle of the gap, Center of roller 1, and Center of roller 2
Ref_pos
mf
Frame mass
m_frame
Jf
0.01
Frame inertia
J_frame
Y
Offset from the reference point in the Y direction
Visualization
Show roller 1
When checked (true), a visualization of roller 1 is created
showVisualization_roller
Show roller 2
When checked (true), a visualization of roller 2 is created
showVisualization_second
Transparent roller
When checked (true) the roller visualization is transparent
transparent_roller
Roller color
Blue
color_roller
Band color
Yellow
color_band
Band angle
20
band_angle
Show frame
When checked (true), a visualization of the frame is created
showVisualization_frame
Transparent frame
When checked (true), the roller visualization is transparent
transparent_frame
Frame color
Orange
color_frame
Advanced Settings
Use effective radius
When checked (true), the roller radius is padded with half the web thickness
useEffectiveRadius
summary_WrapAngle
rad
summary_Length
Length of the web in contact with roller
See Also
Rollers
Web Handling Library
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