No time to 'tech' up my sketches, so thought I'd post the sketches instead. There are two separate devices, both of which use the simple 'snap-action' principles often used in micro-switches etc. Each has one moving part, the 'actuator', plus a stainless steel spring to provide the 'snap' action.Fig 1. Rudder Lock
In it's initial state, the locking pin at one end of the actuator is retracted, so the other end, which has a 'ramp' is protruding into the rudder
1. Down line is pulled, and as the rudder
is almost fully in the rudder
slot, it pushes against the ramp. This causes the actuator to 'snap' over, so that now the pin end is pushed (by the spring) against the rudder
2. As the rudder
fully enters the slot, the pin engages into a hole in the rudder
. The rudder
is now 'locked'.
3. However, as the pin has a hemispherical end, a sharp force against the rudder
(such as running aground) will force the pin out, as it is held only by the force of the spring.
Fig 1:Fig 2. Release Line Mechanism
This mechanism is installed inside the hull, not far aft of the rear hatch for easy accessibility. In this illustration, the rudder
is down. A 'striker ball' has been fastened to the up line. To release the Rudder
1. As soon as the up line is pulled initially, the striker ball engages the slotted end of the actuator, pulling it forward, and thus the Rudder
Lock Release Line, and in turn the actuator in the Rudder
Lock. The Rudder
Lock is now disengaged.
2. As the up line continues forward, the line slides out of the first 'arm' (A) of the actuator, which 'snaps' over, allowing the second 'arm' (B) to engage the up line via it's slot.
3. When the down line is pulled, arm B is pulled backwards by the up line as it returns, and 're-arms' the Release Line mechanism.
Although my sketches look a bit 'complicated', the two mechanisms are quite simple really. To install them does not require removal of the up line etc. There is no constant tension required on the extra Release Line, so it will not affect rudder
The Release Line is routed via a hole drilled in the top of the rudder
housing, then through the up line hull opening:
In an ideal world, this would be produced by Hobie, as they have the engineers who can calculate the sizes/leverage of the actuators and spring strength etc, and the production facilities for the couple of parts required.