Hunting Gear in Hydraulic Steering Gear
(a) Purpose of Hunting Gear:
In a hydraulic steering gear system, the hunting gear acts as a feedback mechanism that ensures the rudder reaches the desired angle and maintains its position accurately. It essentially bridges the gap between the command given from the bridge and the actual movement of the rudder.
(b) Action of the Hunting Gear:
Here’s a breakdown of how the hunting gear functions:
- Command Signal: The helmsman on the bridge operates the steering wheel or controls, sending a signal (electrical or mechanical) to the directional control valve.
- Valve Movement: Based on the signal, the directional control valve directs pressurized hydraulic fluid to one side of the steering gear rams, causing them to extend or retract.
- Rudder Movement: As the rams move, they push or pull on the rudder stock, turning the rudder in the desired direction.
- Hunting Gear Connection: The hunting gear is typically linked mechanically to the rudder stock on one end and to the control system (via linkages or a telemotor receiver) on the other end.
- Feedback Loop: As the rudder reaches the commanded angle, the movement is sensed by the hunting gear through its connection to the rudder stock.
- Adjusting Hydraulic Flow: The hunting gear then transmits a signal (mechanical or hydraulic) back to the control system or the directional control valve. This signal indicates that the desired rudder angle has been achieved.
- Stopping Fluid Flow: Based on the hunting gear’s feedback, the control system or valve might:
- Stop the flow of hydraulic fluid to the rams, preventing further movement.
- Adjust the flow to maintain the rudder at the desired position against external forces (waves, wind).
Benefits of Hunting Gear:
- Accurate Rudder Positioning: Hunting gear ensures the rudder reaches the exact angle commanded from the bridge, improving steering precision.
- Maintaining Rudder Position: It helps the system compensate for external forces that might try to deflect the rudder from its set position.
- Reduced Operator Input: By automatically adjusting for minor deviations, hunting gear reduces the need for constant adjustments by the helmsman.
Overall, the hunting gear plays a crucial role in a hydraulic steering gear system by providing a feedback loop that ensures precise and stable control of the rudder.