Radio control escapement

Used in model airplane and watercraft control ca. 1950 - 1965
A spring is used to return the stop to the neutral position when
the electromagnet coil is not energized

Operation sequence reads clockwise from upper left.

1: Escapement at rest, neutral

2: Escapement coil energized, left (for example)

3. Escapement at rest, second neutral

4. Escapement coil energized, right (for this example)

Variations

Compound escapement

By putting a sight offset (e.g. toward the viewer) in one arm of the rotating blade and cutting back on the rest (inactive coil) stop the device would have only one neutral stop. One directional stop is then always selected on the first pulse and hold. To select the other direction from this single neutral a pulse with brief hold, release, and then hold is commanded.

Four arm escapement

A four-arm version arranged as a "+" does not have the neutral catch remote from the magnet but rather a single catch location with catch points operating on alternate arm pairs depending upon the magnet state. cutting back an appropriate arm will create the compound action described above.

Additional functions

More complex systems have used additional pulse sequences to offer elevator "kick up" so that a loop may be performed after a spiral dive, or up and down elevator control. Such multi-stop systems also have employed electrical contacts to drive a second escapement to control a motor throttle.

I, the copyright holder of this work, release this work into the public domain. This applies worldwide. In some countries this may not be legally possible; if so: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.