Mobile power pack with built-in retractable cable

A mobile power pack comprising:

• a top cover;
• a bottom cover latched to the top cover, the top cover and the bottom cover cooperatively forming a housing, a guide track formed on a bottom surface of the bottom cover, the guide track defining a closed-loop circular channel, the circular channel comprising a first turning point, a second turning point, a third turning point, and a fourth turning point;
• a circuit board;
• a cable comprising a plug, the cable electrically connected to the circuit board;
• a ball;
• a sliding block defining a sliding groove with the ball slidably received therein, the sliding block being arranged on the guide track with the ball partially received in the circular channel, the sliding block being slidable toward a first direction and a second direction opposite to the first direction along a lateral side of the bottom cover;
• and
• an elastic element, one end of the elastic element being connected to the bottom cover, and an opposite end of the elastic element being connected to the sliding block;
• wherein, one end of the cable passes through the sliding block and is connected to the circuit board, an elastic force of the elastic element causes the sliding block to stay in an initial position, where the ball is located at the first turning point, when the plug of the cable is manually pulled out of the housing, the sliding block slides toward the first direction until the ball reaches the second turning point, when the ball reaches the second turning point, the elastic element is stretched, and the ball and the guide track cooperatively prevent the sliding block from sliding toward the first direction, when the pull on the cable is released, the elastic element restores to cause the sliding block to move toward the second direction until the ball reaches the third turning point, when the ball reaches the third turning point, the ball and the guide track cooperatively hold the sliding block in position, when the cable is manually pulled again, the sliding block slides toward the first direction until the ball reaches the fourth turning point, when the ball reaches the fourth turning point, the ball and the guide track cooperatively prevent the sliding block from moving toward the first direction, when the pull on the cable is released, the elastic element restores to cause the sliding block to move toward the second direction until the ball returns to the first turning point.