Selection criteria
232
5.
S
E
LECT
ING CRI
T
ERIA
Sele
cti
on of
the
synchro
nou
s motor and its associated
dri
ve
206
DDS
HARDWARE
Ref.1310
The continuous torque
M
S
:
is due to:
•
the friction between table with its ways and with the ballscrew M
F
,
•
the weight of the table when not moving horizontally M
W
,
•
the cutting force of the tool M
C
.
Friction torque
M
F
:
where:
Torque due to the weight of the table
M
w
:
When the table does not move horizontally, but at an angle
like in figure
the torque due to the weight of the table must also be considered.
If the total table weight is compensated for by means of some sort of hy-
draulic system or counterweights so the motor makes the same effort to
move the table up as to move it down, the
%
factor will be 0. At the oth-
er end, if no compensation is applied,
%
will be 1.
Torque due to the needed cutting force
M
c
:
There is a cutting force between the tool and the part and this means a
hindrance for moving the table. The torque necessary at the motor to
make this movement is calculated as follows:
M
F
Torque due to friction in N·m.
m
Table mass in kg.
d
Leadscrew diameter in m.
g
Gravitational acceleration, 9.81 in m/s².
h
Leadscrew pitch per turn in m.
µ
The friction coefficient between the table and the ways it moves on:
typical µ values depending on material:
Iron
0.1
÷
0.2
Turcite 0.05
Roller bearings 0.01 ÷ 0.02
M
W
Torque due to the weight of the table in N·m.
Inclination angle of the ballscrew with respect to the horizontal axis.
%
Table weight compensation factor that can vary between 0 and 1.
M
C
Torque due to the cutting force of the tool in N·m.
F
Cutting force of the tool in kg-force.
g
Gravitational acceleration, 9.81 in m/s².
MS MF MW MC
+
+
=
M
CONTINUOUS
M
FRICTION
M
WEIGHT
M
CUTTING
+
+
=
MF
MF
TABLE
–
MF
BALLSCREW
–
+
1
i
---
m g
h
2
----------------------------
d
10
------
+
1
i
---
=
=
MW
m g sin
h
2
------------------------------------
%
i
-----
=
MC
F g h
2
-------------------
1
i
---
=
Summary of Contents for DDS
Page 1: ...DRIVE DDS Hardware manual Ref 1310...
Page 6: ...I 6 DDS HARDWARE Ref 1310...
Page 9: ......
Page 10: ......
Page 11: ......
Page 12: ......
Page 16: ...16 Ref 1310 DDS HARDWARE...
Page 30: ...1 DESCRIPTION 30 Description DDS HARDWARE Ref 1310...
Page 94: ...2 POWER SUPPLIES 94 Power supplies DDS HARDWARE Ref 1310...
Page 188: ...3 DRIVE MODULES 188 Drive modules DDS HARDWARE Ref 1310...
Page 204: ...4 AUXILIARY MODULES 204 Auxiliary modules DDS HARDWARE Ref 1310...
Page 232: ...SELECTING CRITERIA 5 232 Selection criteria DDS HARDWARE Ref 1310...
Page 266: ...7 CABLES 266 Cables DDS HARDWARE Ref 1310...
Page 312: ...8 INSTALLATION 312 Installation DDS HARDWARE Ref 1310...
Page 326: ...9 FUNCTIONAL SAFETY 326 Functional safety DDS HARDWARE Ref 1310...
Page 354: ...10 CONNECTION DIAGRAMS 354 Connection diagrams DDS HARDWARE Ref 1310...
Page 378: ...12 SALES REFERENCES 378 Sales references DDS HARDWARE Ref 1310...
Page 384: ...13 COMPATIBILITY 384 Compatibility DDS HARDWARE Ref 1310...
Page 385: ......
