Yes it does, from the rate of rise change in coil primary voltage, as the flywheel magnets swing past the coil/armature.
Edit: I've just read the Atom patent in detail, and firing is triggered when the primary voltage rises to a 'trigger voltage', which is set by the values of certain circuit components.
Last edited by Gadge; 01/06/17 07:10 PM. Reason: correction/elaboration