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Wigwag motor page 1
Wigwag Motors

Magnetic Signal Co.'s "Magnetic Flagman"
The Motor
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click to enlarge
The photos above show both sides of the wigwag motor box. The most important parts are labeled. The wigwag shown is typical of how Southern Pacific shopped their wigwags. Some of the modifications that they did includes GE Pyranol capacitors and two brake springs mounted on either side of the brake shoe. 

Terminal Board

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click to enlarge

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Movable finger contact.

This is the heart of the wigwag motor electrical system. (Along with the movable finger contact) The photo on the left shows an overview of the terminal board. In the very center is the diamond. This is the part that directs the movable finger as it brushes past the contacts. This is one of the few parts that need to be greased. The photo to the right shows the two contacts. These need to be kept free of rust, dirt and grease. Each contact is connected to one set of magnets. When the movable finger brushes across one contact, it energizes one set of magnets and pulls the armature to that side. As the finger moves past the contact, the circuit is opened, and the armature returns. The diamond directs the finger contact to the other contact plate, energizing the other magnet. This is what causes the swinging motion of the wigwag.

Wigwag Bell Mechanism

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Striker Hub Assembly. Click on photo
for larger view and part labels.
I will try to explain this as simply as I can...
The bell housing is held to the wigwag motor box with three bolts. After removing the housing, this is what you will find. Starting from the center is the "end of flagman armature". The stationary bell tripper is held in place with a cotter pin. (The tips of the bell tripper may become worn, and will eventually fail to trip the striker key) As the armature rotates, the bell tripper pushes the striker key up. When the armature is at the end of it's swinging cycle, it lets go of the key. This causes the striker assembly to drop, which causes the hammer to hit the gong. This happens on each swing of the armature, causing the bell to ring one time in each direction.

More to be added to this section including WRRS
 and US&S soon!

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