Linkage mechanism for folding power plug blades

A linkage mechanism for a power plug device, the power plug device having a casing, a first prong and a second prong, an outer face of the casing formed with a receiving recess, the first prong and the second prong each pivotally arranged in the receiving recess respectively through pivotal connections between the bottom end of the first prong and the casing and between the bottom end of the second prong and the casing, the linkage mechanism disposed inside the casing, the linkage mechanism comprising:

• a linkage member having a guiding groove;
• a first link, a first end of the first link being fixed to the bottom end of the first prong, and a second end of the first link being disposed in the guiding groove;
• and
• a second link, a first end of the second link being fixed to the bottom end of the second prong, and a second end of the second link being disposed in the guiding groove;
• wherein
• the distance between the first end of the first link and the first end of the second link is greater than a maximum distance between the second end of the first link and the second end of the second link;
• when the first prong rotates relative to the casing, the second end of the first link slides in the guiding groove, the linkage member is driven to move, and the second end of the second link is in turn driven to slide in the guiding groove in the opposite direction as the second end of the first link slides, causing the second prong to rotate in the opposite direction as the first prong does.

A power plug device, comprising:

• a casing, an outer face of the casing formed with a receiving recess, and an inner face of casing has a sliding rail;
• a first prong and a second prong, the first prong and the second prong each pivotally arranged in the receiving recess respectively through pivotal connections between the bottom end of the first prong and the casing and between the bottom end of the second prong and the casing, and
• a linkage mechanism disposed inside the casing, the linkage mechanism comprising:
• a linkage member having a guiding groove and slidably disposed at the sliding rail, wherein the sliding rail extends in a first direction, and the guiding groove extends in a second direction, and the first direction is perpendicular to the second direction;
• a first link, a first end of the first link being fixed to the bottom end of the first prong, and a second end of the first link being disposed in the guiding groove;
• and
• a second link, a first end of the second link being fixed to the bottom end of the second prong, and a second end of the second link being disposed in the guiding groove;
• wherein
• when the first prong rotates relative to the casing, the second end of the first link slides in the guiding groove, the linkage member is driven to move, and the second end of the second link is in turn driven to slide in the guiding groove in the opposite direction as the second end of the first link slides, causing the second prong to rotate in the opposite direction as the first prong does.