6
PUMP COMPONENTS
SPRAY GUN:
The spray gun is designed
specifically for airless spraying.
Since there is no compressed air
to atomize the paint, atomization
is accomplished by forcing the
paint at a very high pressure
(3200 psi) through a very small
hole (.017" diameter). Because
of this high pressure, the spray tip
and gun valve are made of
tungsten carbide for maximum
wear resistance. The gun body is
made of forged alloy and ano-
dized for chemical resistance.
As a safety feature, the spray gun
can be locked with the trigger
safety lever when you are not
spraying. Be sure to read all
warnings concerning the high
pressures of airless spraying on
page 3 & 4.
PISTON PUMP (DC-3000 & DC-4000):
Uses two sets of packings and two check valves in
conjunction with an abrasion resistant piston. This forms
a double acting pump; ie pumps on both up and down
stroke. Both sets of packings are stationary, eliminating
costly cylinder wear.
CENTRAL BODY (DC-4000):
Is a meeting point of pump and speed reducer. Helps
turn rotating motion of motor and reduce into an even up
and down motion to drive pump.
SPEED REDUCER(DC-3000):
Consists of a two stage gear reduction in permanent
grease for long life. All bearings are alsopermanently
greased. Converts the high speed output of motor into
very high torque to drive pump.
SPEED REDUCER (DC-4000):
Consists of a single stage gear reduction in an oil bath for
long life. All major bearings are also lubricated by this oil.
Converts the high speed output of motor into very high
torque to drive pump.
MOTOR (DC-3000):
Is an industrial grade high speed unit. Its permanent
magnet DC type construction withstands construction site
power fluctuations. The higher rpm of this motor results in
a compact and lightweight design.
MOTOR (DC-4000):
Is an industrial grade high quality unit. Due to the perma-
nent magnet DC type construction, the motor will run at
different speeds, depending on how much voltage it is
sent by pressure control box. This allows for highly
accurate control of pressure.
Motor also features long life brushes, which are readily
accessible from the outside.
PRESSURE CONTROL BOX (DC-3000):
A rugged membrane transducer transmits a paint pres-
sure signal to an electronic relay which then powers the
motor. This on-off design has a pressure fluctuation of
about 200 psi.
PRESSURE CONTROL BOX (DC-4000):
It balances input from the pressure control box with a
signal from the sensor. On the basis of these two inputs,
and electronic decision is made regarding how much
voltage, if any, is required by the motor to maintain an
even pressure. The more pressure set by operator, or
pressure drop from a large tip, the more voltage is sent to
motor to speed up the pump. When the gun is released,
the pressure rises and the motor is turned off.
The advantages of this system will become most obvious
if you try smaller tips (.011/.013) at lower pressures for
lacquering or other fine work.
A safety circuit is also incorporated which will turn the
pump off if it runs out of paint at spraying pressures.
(above approx. 1000 psi) If the unit drops from spraying
pressure to below approx. 500 psi, for more than 25
seconds continuously the safety will turn the pump off.
This is to reduce the typical packing damage from “dry”
running. At pressures below approx. 1000 psi, the safety
will not engage, making the unit fully compatible with all
types of pressure rollers. It also prevents interference of
the safety with typical cleaning procedures.
(trigger shown in horizontal
locked position)
locked
unlocked
Important
To engage trigger
safety lock, turn
lever tab to horizon-
tal position. Test
regularily for proper
functioning while
system is shut
down.
For models
L45 & L-50
Figure 1b. - DC-4000 components.
motor
pail hook
suction pipe
return hose
control box
speed reducer
grease fitting
central body
paint pump
brush cap
suction screen
Figure 1a. - DC-3000 components.
paint pump
prime valve
motor
pressure control
control box
speed reducer
prime valve
suction
system
