Oyama rice cooker - uncooked rice under heating element
This question is on-topic enough I'll take a shot at it. First of all, don't try to cook with this without getting the rice out as it's a potential fire hazard. You probably know this but it's worth saying!

Now how I'd attack this is to grab a screwdriver and take the thing apart, which is probably easy to do. If you do decide to try it take lots of pictures as you go so you can put it back together. 

If that's not a step you're willing to try then it's guaranteed to be physically possible to get the rice out without taking it apart because the rice got in to begin with, it's a matter of getting it tipped to the right angles at the right time. The best way to do this is to shake it - a lot, upside down or tipped the right direction for the rice to come out. Tip it around at all angles, work it loose and then tip it back to the angle it can fall out. Do it again and again until it the rice is gone. It may take awhile doing it this way, and I'd suggest running the machine outside the first time after using this method in case you miss anything.