Siemens SINUMERIK 840D Description Of Functions page 31

02.99
Mounting
Mounting position
Seal, Friction
Cylinder pipes
Position
measuring system
 Siemens AG 2000. All rights reserved
SINUMERIK 840D/SIMODRIVE 611 digital Descr. of Functions HLA Module (FBHLA) – 04.00 Edition
In the interest of obtaining high control quality, the cylinder must be mounted by
a backlash-free method, such as flange or base mounting.
Flange mounting
Flange at front
Ì
Ì Ì
Ì
Ì
Base mounting
Ì Ì Ì Ì Ì Ì Ì Ì
Ì Ì Ì Ì Ì Ì Ì Ì
Fig. 2-7 Cylinder mounting methods
This is dependent on the machine situation and affects the selection of shutoff
valves (see Section 2.3.3). Vertical loads must be protected via poppet valves.
Forces due to weight must be taken into account in the final calculation of the
operating pressure
(MD 5151: CYLINDER_A_ORIENTATION).
Fig. 2-8 Cylinder mounting position
Low friction can be maintained by using suitable seals. Transitions from static to
sliding friction have a particularly adverse affect on the control result.
The slide guide friction must be added to the cylinder friction. A friction com-
pensation function can be activated in the HLA module (MD 5460:FRIC-
TION_COMP_RADIENT) in order to overcome initial friction.
The distance between the cylinder and servo solenoid valve must be kept as
short as possible for the sake of the frequency (compressibility of oil volume). In
ideal cases, the servo solenoid valve is flange-mounted directly on the cylinder.
The incremental and absolute position measuring systems supported by the
HLA module are mounted on the machine slide. The HLA module does not sup-
port cylinder-integrated position measuring systems (magnetostrictive or poten-
tiometer).
2.3 Configuring the hydraulic drive
Flange at rear
Ì Ì
Ì Ì Ì Ì
Ì Ì
Ì Ì
2 Configuring
2-31