Hamilton Jet HJ241, Manual

Page: 48 / 202

3.14
3 DESIGN BASICS
3.6 HSRX R
EVERSE
S
YSTEM
D
ESCRIPTION
HJ-241 / HSRX
3.6 HSRX REVERSE SYSTEM
DESCRIPTION
The Hamilton HSRX Reverse System is a self
contained Hydraulic Reverse Actuation System.
The actuation is provided by a Hydraulic Reverse
Cylinder that uses a rotary valve inside the cylinder
to give variable progresssive positioning control.
This allows fast control response where accurate
posistioning is not required (from the fully up
position to just prior to the Reverse Duct entering
the waterjet) and fine control of the Reverse
Cylinder position where it is needed (around the
Zero Speed / Reverse position).
With the Piston restriction (A) fully open, equal
pressure acts on both the rod end and cap end of the
HSRX Cylinder. As the cap end area is larger than
the rod end area, the cylinder extends.
With the Piston restriction (A) closed, the Cylinder
retracts. At full retraction, the Bypass Valve (B)
opens, reducing the system pressure and power
consumption of the pump.
The Back Pressure Valve (3) Is factory preset at 3.45
MPa (500psi).
The Pump Assembly (1) is belt driven directly from
the Jet Unit.
The Pump Assembly comprises, Pump, an Integral
Tank, Flow Control and Pressure Relief Valves.
3.6.1 Basic Hydraylic Circuit
Refer to Drawing CT-HSE-12-001 Hose Kits .
Table 3: Hydraulic Circuit Items
ITEM
NO.
DESCRIPTION
A Variable Restriction with Cylinder posi-
tion feedback.
B Bypass Valve. (Open when Cylinder is
fully retracted).
1 Pump Assembly.
2 HSRX Cylinder.
Minimum oil flow 3 litres per minute.
Maximum oil flow 16 litres per minute.
3 Back Pressure Valve.
4 Oil Cooler (Part of Jet Assembly).
Figure 23: Hydraulic Circuit Diagram