Metal plate punching device

The utility model discloses a sheet metal punching device, and relates to the field of sheet metal machining. According to the scheme, the device comprises an operation table, two mounting plates are slidably connected to the top of the operation table, supporting rods are fixedly connected to the two sides of the bottom of each mounting plate, two second limiting grooves are formed in the top of the operation table, and locking mechanisms for locking the sliding positions of the supporting rods are arranged in the second limiting grooves; three rectangular columns are transversely and slidably connected to the interior of the mounting plate, a lower pressing plate is slidably connected to the bottoms of the rectangular columns, adjusting mechanisms used for adjusting lifting of the lower pressing plate are arranged in the rectangular columns, and a moving mechanism facilitating moving of the rectangular columns is arranged in the mounting plate; and the positions of the two mounting plates and the distance b