BIO-MED DEVICES IC-2A Service Manual page 18

The five Logic Gate ports are generally used as follows:
Ports 1 and 2
Port 3
Ports 4 and 5
Pressure to Ports 1 and 2 actuate a diaphragm assembly allowing either Port 4 or 5 to
connect with Port 3.
interconnected. An input to Port 1 switches the diaphragm assembly causing Port 5 to
close and Port 4 to open resulting in a connection between Ports 4 and 3. Equal
pressures on both Ports 1 and 2 allow the spring to keep the diaphragm assembly in a
position where Ports 5 and 3 are connected.
Figure 2-3 illustrates the physical aspects of the Logic Gate in a cutaway view and also
provides a functional view.
1
Switching Signals
Output Signal
Supply or Exhaust
With no input on either Port 1 or 2, Ports 5 and 3 are
5 3 4 2
Fig. 2-3 Logic Gate, Cutaway & Schematic Views
2 4
3
1 5
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