Patent ID: 8402782

Claim:
An ice-making device for a refrigerator, comprising: an ice tray defining an ice-making space; a freezing core that is partially received in the ice-making space to form ice at an end thereof; a driving unit generating a driving force that causes vertical and rotational movement of the freezing core; and a power transmission unit to transfer power from the driving unit to the freezing core, the power transmission unit comprising: a cam rotatably connected to the driving unit; and a moving member communicating with the cam and following a vertical and a rotational path as guided by the cam; and a first shaft coupled to the moving member, the first shaft extending from a surface of the moving member in a first direction; a second shaft disposed at a site spaced apart from the first shaft in a lengthwise direction of the moving member for guiding a vertical movement of the moving member, the second shaft extending from the surface of the moving member in the first direction; wherein the cam includes: a main body; guide grooves formed at the main body, the grooves comprising a first groove receiving at least a portion of the first shaft and a second groove receiving at least a portion of the second shaft, and wherein the second groove surrounds the first groove; a first protrusion defining a boundary between the first and second guide grooves to guide the movement of the first shaft; and a second protrusion disposed at inner side of the first protrusion to guide the movement of the second shaft, the second protrusion being surrounded by the first groove.