[HH] Opening a skull (on topic, honest!)

[Tom Metro]

Mark Komarinski wrote:
> Ah, a friend gave me [a solenoid] that is in two pieces (the inner shaft can be
> removed from the solenoid).

Yes, that's a typical design. The first of the two products I linked to
is like that.


> The range of movement was rather small but
> after thinking about it may be enough to get the jaw to open. 

A lever will increase the travel. Or just find a different solenoid with
a longer travel.

If you don't need a lot of force, and have a solenoid with a removable
plunger, you can stretch beyond the manufacturer's travel specification,
but I believe the force decreases following the inverse square of the
distance.

Automotive door look actuators can be a good source for fairly long
travel solenoids (technically I think some are motors). This one:

http://www.amazon.com/HIGH-POWER-DOOR-LOCK-ACTUATOR/dp/B0002KR9PW

has 3/4" travel, and instead of using a spring return you reverse polarity.

 -Tom