Kärcher HD 6/16-4 M / MX Service Manual page 18

Servopress rotary regulator partially closed:
1 Manometer
2 Pressure holding valve
3 Pressure room with pressure valves
4 Pressure switch
5 Connecting boring to overflow valve
6 Overflow valve ball
7 Connecting boring to suction room
8 Piston rod
9 Connecting boring from the overflow valve
to the control pressure injector
10 Detergent injector
11 High pressure outlet
12 Control pressure injector
Trigger gun closed:
18
English 5.906-246.0 Rev. 01 (09/14)
With the power press regulator partially closed, the pres-
sure in the pressure room will not rise any further. Howev-
er, due to less water volume, the effect of the control
pressure injector decreases, so that the pressure in the
Q2
connecting boring rises. Thus, the piston rod is pressed
slightly to the right against the spring pressure. The cone
tip of the rod slightly pushes the ball out of its seat so that
a part of the flow rate flows to the suction chamber.
The pressure switch is slightly pushed to the right due to
the increased pressure in the connecting boring, but not far
enough to switch off the pressure switch.