Abstract: A swivel plate device has a base plate, a rotating plate disposed on the base plate, and a cover covering the rotating plate. The base plate has a center hole, an annular groove, an annular protuberance, and positioning holes. A chain-shaped ring has round holes. A plurality of balls are inserted in the round holes. The rotating plate has a central through hole, a plurality of oblong holes, an annular recess, an annular protrusion, an annular channel and a post. A rivet passes through an annular bearing, the central through hole, and the center hole. A pillar is disposed on the rivet. A spring has a first end hook hooking the pillar and a second end hook hooking the post. A rim of the cover is inserted in the annular recess. The chain-shaped ring is inserted in the annular groove and the annular channel.