A can opener contains: a first holder, a second holder, a transmission device, an eccentric gear, a rotating roller, a connector, a washer, a guiding roller, and a metal piece. The first holder includes a battery chamber, a cover, and a first switch. The second holder includes a first accommodation room, a plurality of first posts, and a second accommodation room. The transmission device includes a motor, a plurality of first driving gears, and a second driving gear. The eccentric gear includes an opening and a plurality of coupling pillars. The rotating roller includes a second post, and the connector includes a second arcuate orifice, a plurality of second coupling stems, and two second positioning pillars. The washer includes a third arcuate orifice and a fixing hole. The guiding roller includes a first pore and an abutting portion, and the metal piece includes a second pore and a contacting gear.

Can opener includes a shell, power mechanism, transmission mechanism, and cutting mechanism. The transmission mechanism includes a main drive gear, eccentric disc, and movable block. The main drive gear and eccentric disc are coaxially arranged, and the surface of the main drive gear facing the eccentric disc is provided with a linkage groove. The movable block is arranged on the eccentric disc in a liftable manner to insert into or withdraw from the linkage groove. One side of the movable block is provided with a first inclined surface and a first vertical surface, and the other side is provided with a second vertical surface. When the main drive gear rotates forward, the linkage groove abuts against the first vertical surface to drive the eccentric disc to rotate forward. When it rotates forward beyond the limiting position, the linkage groove slides relative to the first inclined surface to stop driving the eccentric disc to rotate forward. When it rotates backward, the linkage groove abuts against the second vertical surface to drive the eccentric disc to rotate backward.