These are views of the Thomas Orchestra Bells as I received the instrument.  I was disappointed by the synthetic casework, but discussing it with other folks it made sense for a mass-produced object from Thomas Organ Company.  The design is super simple with a row of solenoids below the tone bars.  It didn't use return springs, relying on gravity to drop the striker back into the coil.  

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Thomas orchestra bells

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Orchestra bells open

Peeking under the tone bars you can see the solenoids lined up and ready to strike:

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Orchestra bells action