IAI America ERC - Manual (Page 92)

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6. Operation in the “3 Points (Air Cylinder)” Mode
6.1 Overview of the “3 Points” Mode
This mode provides a control method adjusted to that of an air cylinder by assuming that the ERC is used as an
air cylinder.
The key differences between the ERC and an air cylinder are summarized below. Perform proper control by
referring to this table.
Item Air cylinder ERC
Drive method Air pressure supplied
via electromagnetic
valve control
Ball screw/timing belt driven by a motor
Target
position
setting Mechanical stopper
(including shock
absorber) Desired coordinates are entered in the [Target position] field of the
position table.
The coordinates can be typed in from the number keys on the PC
keyboard or on the teaching pendant, or set directly by moving the
actuator to the target position.
Target
position
detection An external detection
sensor, such as a reed
switch, is installed. Determined based on the internal coordinates provided by the
position information from the position detector (encoder).
Accordingly, external detection sensor is not required.
Speed
setting Adjusted by a speed
controller. A desired feed speed is entered in the [Speed] field of the position
table (unit: mm/sec).
Note that the rated speed is automatically set as the initial value.
Acceleration/
deceleration
setting Determined in
accordance with the
load, supplied air
volume, as well as the
performance of the
speed controller and
electromagnetic valve. A desired acceleration/deceleration is entered in the
[Acceleration/deceleration] field of the position table (unit: 0.01 G).
(Reference) 1 G = Gravitational acceleration
Note that the rated acceleration/deceleration is automatically set
as the initial value.
Since the acceleration/deceleration can be set in fine steps, a
gradual acceleration/deceleration curve can be programmed.
Position
check upon
power ON Determined by an
external detection
sensor, such as a reed
switch. Immediately after the power is turned on, the controller cannot
identify the current position because the mechanical coordinates
have been lost.
Therefore, when the first movement command is issued after the
power has been input, the controller will automatically perform
home return before moving the actuator to the target position.
[1] The actuator moves at the home return speed toward the
mechanical end on the motor side.
[2] The actuator hits the mechanical end and turns back, and then
stops temporarily at the home position.
[3] The actuator moves to the target position at the speed
specified in the [Speed] field of the position table.
(Note) Pay attention not to allow any obstacle in the travel
path of the actuator during home return.
Home
position
[1]
[2]
[3]
Power is turned on here.
Target position