M6 SERIES IOM
6th EDITION
ISSUED 12/2014
9
IV. Operation
A. Principals of Operation (Double Acting)
The Contromatics pneumatic actuator has simple operational characteristics. Port A is connected to the interior
cavity between the pistons. Port B is connected to the end cap cavities (See Figures 4.1-4.2 below). If port A is
pressur- ized (Fig. 4.1), air flows between the two pistons pushing them apart. Air is, in turn, exhausted out of port
B and the pinion is rotated until the pinion cam is stopped by the open limit stop, resulting in the open position of
the actuator. In order to rotate the actuator back to the closed position, air pressure must be removed from port A
and applied to port B. Pressurizing port B (Fig. 4.2) will allow air to move into the cavities between the pistons
and the endcaps pushing them together. Air is, in turn, exhausted out of port A and the pinion is rotated until the
pinion cam is stopped by the closed limit stop bolt, resulting in the closed position of the actuator.
The above illustrations show the paths taken by the pressurized air (blue), the exhausting air (red), and the resulting
state of the actuator.
B. Principals of Operation (Spring Return)
The opening stroke of the spring return model functions just like the double acting model. By pressurizing port A
as shown in Fig. 4.3 the actuator opens, exhausts air like the double acting model, and compresses the springs.
However, to close the actuator, air pressure is removed from port A and allowed to exhaust. Once this is done the
encapsulated springs will return the actuator to its closed position and air will be exhausted out of the A port as
detailed in Fig. 4.4 below.
The above illustrations show the paths taken by the pressurized air (blue), the exhausting air (red) and the resulting
state of the actuator.
A Port
B Port
A Port
B Port
A Port
B Port
A Port
B Port
NOTE:
In the case of a spring return model even though port A is the only port that needs to be pressurized in
order to operate the actuator, air still must be allowed to enter and exit through port B unobstructed for proper
operation. Contromatics both recommends and supplies filters or recirculation blocks that will maintain airflow
but prevent debris from entering the actuator. Consult Contromatics for specific applications and more
information.
