It appears to be an interface board in front of a more
or less ordinary
floppy drive, though I suspect appearances are deceptive, since I don't
see any power feed to the front-end board except possibly over what
looks like an ordinary floppy interface - but an ordinary floppy
interface does not supply power from the drive to the ribbon cable.
It's not unheard-of. Typically, the odd-numbered pins were used for
power. On a 'normal' (as you called it) floppy drive, all are grounds. On
a drive with power o nthe ribbon cable, theyr'e split into 3 groups for
+5V, ground and +12V.
The SOny drive used in the HP9114B (the half-height drive that shares
parts with an Apple 800K drive) has soldered SMD jumpers to select either
'all grounds' and a spearate power connector or power over the ribbon
vable, the 9144B uses the latter option. 'My' scheamtics for this unit
should show it.
-tony