Figure 6.1 Press-Mate Pneumatic System
The Press-Mate determines blood pressure using the oscillometric method. Measurements are taken during cuff
deflation, which is controlled by a micro-computer. Cuff pressure is deflated at a rate of 3 to 5 mmHg per
second or per heart beat during blood pressure measurement. Rapid cuff deflation occurs under the following
circumstances:
• When measurement is completed.
• When measurement is interrupted by pressing the START/STOP switch.
• When cuff pressure exceeds 325 mmHg.
The following sequence of events occurs when the pump is turned on by pressing the START/STOP switch on
the front panel:
1. Air is immediately dispensed throughout the entire pneumatic system (Figure 6.1).
2. Once the pneumatic system is pressurized to 180 mmHg (120 mmHg in the neonatal mode), the pressure
transducer on the main CPU board cuts power to the pump.
3. Air is then passed through he bleed valve so that the cuff pressure is decreased in a linear fashion and
exhausted back through the pump.
6-2
6.2
Pneumatic System
Air Manifold
Transducer
Over
Pressure
Switch
Air Tube A
Air Tube C
L Tube
L Tube
L Tube
Air Tube B
Bleed Valve
Dump Valve
Cuff
Main CPU
Board
Pump