Unit Function
HDS Middle Range / HDS Premium Range
Page 52 / 127
Service Manual 04.2008
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3
5 1
2.23 Pressure and flow control valve with rotary control
The pressure and flow control valve is designed
as a rotary control between the handgun and
spray lance.
There are two ceramic discs (1, 2) inside the
high-pressure duct.
The ceramic disc (2) is rigidly connected to the
handgun connection (6). The ceramic disc (1) is
connected to the rotary control (5) and can
therefore be adjusted. The holes in the ceramic
discs (1, 2) are staggered; this enables the flow
rate and pressure to be varied when the discs
are rotated.
The diagram shows the two superimposed
ceramic discs (1, 2) and the water flow (blue) at
various opening angles of 0° - 90°.
At the minimum setting the water flows through
a small hole in the middle of the ceramic discs
(1, 2).
1 Ceramic disc - spray lance side
2 Ceramic disc - handgun side
3 Handle, rotary control
4 Connecting pin
5 Housing, rotary control
6 Handgun connection
7 Spray lance connection
Water flow at opening angle 0° - 90°
Cross-section through the rotary control (handgun
side)
Long-section through the rotary control
6
2
7
1
0°
10°
20°
30°
40°
50°
60°
70°
80°
90°
2
4
3
2
5