Watson-Marlow SP40 - Manual (Page 16)

DESCRIPTION
13
4.4 Description of Bredel hose pump with
special rotor construction for CIP cleaning
The pump has a special rotor that contains 2 standard
pressing shoes. These pressing shoes can be adjusted
by shims, same as with standard pumps. Every
pressing shoe is, at one side, connected to the rotor by
a pivot-arm Construction. In the centre of this pivot-arm
is a roller (A).
Attached to the inside of the special pump cover is a
shaft with a cam (B), that can be moved manually or by
an actuator (electrically or pneumatically) that is
mounted at the outside of the pump cover.
When the cam (B) is in neutral position, it does not
touch the roller (A) of the pivot-arm inside the pump.
When the cam (B) is turned over about 120° (position
1), the roller (A) will follow the cam (B), thus pushing the
pivot-arm outwards (position 2).
Resulting from this movement, the pressing shoe is
retracted from the pump hose. Once retracted the shoe
rests on the hose (position 3). Now the pump hose is
and remains fully opened. The pump can be stopped
and the hose can be flushed/cleaned. When the
retracted shoe is leaving the compression area (in
between the ports) the attached spring will force it back
into normal position.
A
B
A
B
POSITION 1 120°
POSITION 2
R1