Maurice is Belle's father, a would-be "world-famous inventor" whose crackpot contraptions have earned him a reputation as a weirdo in the village. How can we tell he's a bit off? By his absolute lack of self-awareness and endless absorption in his work. He's the stereotypical nutty professor, with his head in the clouds about all the great things he's going to invent but an inability to so much as pull up his pants without help.
And yet, he's more than just a clown, or the "harmless crackpot" that LeFou sings about.
For one thing, his inventions actually work—or, at least, the wood chopper does. That means he really has some sound reasoning behind all of his tinkering. And, he adores Belle. He almost kills himself searching for the castle where she's being held, and she's in turn willing to leave the Beast she loves in order to make sure he's safe and sound.
That's some serious devotion the two of them have for each other, which highlights one of the movie's subtler points about love. Sure, it's about finding that special someone, but it also means caring about a family member or friend so much you'd be willing to risk life and limb for them. Belle is beautiful in part because she loves her father so much, and Maurice returns that love and devotion in kind.
That's also important from a plot perspective because it gives Belle someone worth going back to the village for. In some ways, Maurice is the only real member of any community she has before she finds the castle. They're both outsiders—like father, like daughter on that front. He's got those same qualities (brains, a quirky perspective) that keep Belle from finding any real friends among the villagers. It binds them together all the more deeply and reminds us that, while they may live in the village, neither of them will truly belong there.