Button sewing machine and feeding device thereof

The utility model discloses a button sewing machine and a feeding device thereof, the feeding device comprises a driving cylinder, an adjusting plate group, a first clamp and a second clamp, the adjusting plate group is hinged with the driving cylinder, and the first clamp and the second clamp are respectively in sliding fit with a first adjusting groove and a second adjusting groove arranged on the adjusting plate group. The first adjusting groove and the second adjusting groove are distributed in a horn shape. When the driving air cylinder is started, the driving air cylinder drives the adjusting plate set to slide relative to the first clamp and the second clamp, the first adjusting groove and the second adjusting groove jointly guide the first clamp and the second clamp to be close to each other or separated from each other, and therefore the first clamp and the second clamp are opened and closed. The original indirect connection between the driving cylinder and the adjusting plate group is changed into d