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Introduction
Inlet
Spring
Outlet
Diaphragm
Pump shaft
Constant-velocity cam
Inlet
Outlet
Pump mechanism
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Flow pulsation reduction mechanism
The reduction mechanism consists of the two factors. One is the use of a highly-precise constant-velocity cam,
which makes a trapezoidal waveform of each discharge. The other is the phase shift of two different discharge,
The rear head moves out of phase with the front by 180 degrees to make a constant synthesized waveform.
The flow rate of the TD can change with a motor rotation speed (inverter frequency).
*
Note suction pulsation is not reduced
.
Constant-velocity cam and Phase shift
Discharge/Suction waveform
NOTE
The mechanically-driven diaphragm pump including the TD by its nature involves flow pulsation during op-
eration. The reduction mechanism can reduce but can't eliminate the pulsation completely, and the pulsation
becomes greater as a discharge pressure gets higher. This is because the diaphragm transiently depressed
under a high pressure as with every other mechanically-driven diaphragm pumps.
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Constant synthesized waveform
Front head
One cycle
Rear head
Discharge/Suction volume of the front head
Discharge/Suction volume of the rear head
Total discharge volume consists of both heads
Discharge process
Suction process
