Actually Ice O Matic machines use a similar system. Once the freeze timer has timed out the machine enters in harvest mode (purge, hot gas and harvest motor are activated) until the ice drops to the bin and the cam switch is reset and the curtain switch is toggled.
This control scheme is great, IOM actually switched to electronic controllers years ago but and had to switch back to electromechanical controls because people complained that the electronics were hard to troubleshoot.
If you want to see the mother look around for Vogt tubular Ice machines with a Carrier open drive compressor ....