Low rotational speed gear module

A low rotational speed gear module, comprising:

• a fixed tube member (1) including a first inner gear (11);
• a rotational sleeve (2) disposed corresponding to the fixed tube member (1) and rotatable with respect to the fixed tube member (1), the rotational sleeve (2) including a second inner gear (21), the first inner gear (11) and the second inner gear (21) together defining an accommodating space (s) inside them;
• a first planetary gear set (3) received in the accommodating space (s), the first planetary gear set (3) including a fixing plate (31), a plurality of first planetary gears (32) fixed to one side of the fixing plate (31), and a driven gear (33) fixed to the other side of the fixing plate (31);
• a sun gear (4) disposed among the first planetary gears (32), each of the first planetary gears (32) being engaged at one side with the sun gear (4) and engaged at another side with the first inner gear (11), so that the driven gear (33) is rotated by rotation of the first planetary gears (32);
• and
• a second planetary gear set (5) disposed around the driven gear (33), the second planetary gear set (5) including a plurality of second planetary gears (51), each of the second planetary gears (51) being engaged at one side with the driven gear (33) and engaged at another side with the first inner gear (11) and the second inner gear (21), so that the rotational sleeve (2) is rotated by rotation of the driven gear (33);
• wherein the second planetary gear set (5) further includes two clamping plates (52), the second planetary gears (51) are arranged in a circular manner at equal distances from each other, and the second planetary gears (51) are interposed between the two clamping plates (52) and are pivotally connected to the two clamping plates (52);
• wherein one of the clamping plates (52) includes an open hole (521), and the driven gear (33) is inserted in the open hole (521).