minecart mod

hey guys i was recently mining out a massive dungeon looking for ores and every time i got heaps of them i had to keep running back up the put them into the chest so i started thinking is there any way this could be simpeler so i came up with this idea.

A storage minecart not much use but if it could automaticly store items into a chest as it goes past it
eg. X X C X X
T T M T T
The X is nothing the C is a chest and the T is minecart track and the M is the minecart with the chest so as it passes it at automaticly deposits the ore and comes back down the to the mine where i can redeposit more ores then activate it to go back up i dont know if this had been made yet i done some research and didnt find anything so.
If someone does make it please give credit to me.