KNF LABOPORT N820.3FT.29.18G, Manual

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Design and function
Chemically-resistant Laboratory pump N820.18
EX
24
Translation of Original Operating Instruction, English, KNF
317428-317425 09/20
Function of a diaphragm pump
1 Outlet valve
2 Inlet valve
3 Transfer
chamber
4 Diaphragm
5 Eccentric
6 Connecting
rod
7 Pump drive
Fig.4: Function of a diaphragm pump
Diaphragm pumps transfer, compress (depending on the ver-
sion) and evacuate gases and vapors.
The elastic diaphragm (4) is moved up and down by the ec-
centric (5) and the connecting rod (6). In the downwards
stroke, it aspirates the gas to be transferred via the inlet valve
(2). In the upwards stroke, the diaphragm presses the medium
out of the pump head via the outlet valve (1). The transfer
chamber (3) is separated from the pump drive (7) by the di-
aphragm.