(3) Line number 7 from the air and water utility module feeds a regulated air signal
to the system air pressure gauge located in the utility module.
(4) Another regulated air line, number 8, from the utility module feeds the foot
switch. The foot switch becomes the source for air for the following systems.
(a) System drive air.
(b) Coolant air.
(d) Water coolant signal air.
(5) A line, number 9, from the control block feeds the drive air pressure gauge.
Coolant air and drive air are supplied through the master block to the control blocks for
the individual handpieces. Regulated air is supplied through the master block to the
individual handpiece hangers number 10.
b. Water is supplied to the unit in the same fashion that air is processed. A pilot
air signal, located near the water closet valve, opens the air actuated diaphragm in the
water relay valve enabling unregulated water to enter the air and water utility module
through line number 5.
(1) An air operated diaphragm, within the water pre-regulator, adjusts the
system water pressure which can be read on the water pressure gauge number 11.
(2) Water is supplied from the air and water utility module to the water
heater tank (if supplied). From the tank, heated water flows to the master control block,
number 12, and is distributed to the individual handpieces and the accessories.
DENTAL OPERATING UNIT COMPONENTS
a. Master Block Assembly. Refer to figure 4-2. The master block houses the
master ON-OFF valve, the ON-OFF indicator, the air coolant flow control, the water
coolant ON-OFF valve, and the syringe flow controls. All the working components are
accessible from the front of the unit and are of the "cartridge" design, so they can be
serviced without disconnecting any tubing.