Positioning Cam; Positioner Cam Characteristics - ABB AV3 Instruction Manual

INSTALLATION
MOUNTING TYPE AV3 AND AV4 POSITIONERS
3 - 6
4 5° C A M
AV ? ?1 ?? ??
Figure 3-5. Positioning Cam
Table 3-1. Positioner Cam Characteristics
Positioning
Cam Any
Stroke
A
B
C
The cam, camshaft and drive arm rotate as an assembly. Cam
motion is 90 degrees (AV
depending on positioner type specified by nomenclature.
Each cam shape (A, B or C) has its own eight-point center hole for
mounting on the camshaft (Fig. 3-5). Place the drive arm in any of
eight 45-degree positions with respect to the cam. This provides
flexibility in arrangement so that the midpoint of the cam will corre-
spond to the mid stroke of the actuator.
3. Adjust the connecting linkage so that the zero radial line on
the cam intersects the center of the cam roller (Fig. 3-6).
4. Lock all linkage components in place.
R A D IAL
LIN E S
9 0° C A M
AV ? ?2 ?? ??
Piston or Valve Position
(P) vs Control Signal (I)
Square Root (I = √P)
Linear (I = P)
2
Square (I = P )
2 ) or 45 degrees (AV
C O N C E N T R IC
AR C S
T 00 80 5 A
Figure
Number
C-1
C-2
C-3
1 )