A balanced speed reducer of a dual-ring gear variable-line-speed planetary row, comprising a dual-ring gear variable-line-speed planetary row, an input end, an output end, a locking end and a bearing auxiliary device, characterized in that, the dual-ring gear variable-line-speed planetary row comprises a left ring gear, a right ring gear and a planet carrier with planetary gears, the planet carrier supports the planetary gears, and distances from planetary gear axes to a revolution axis, which are reference center distances, are equal;
- on a gear axis of each planetary gear, two gears, namely, a left planetary gear and a right planetary gear, are arranged in sequence;
- each set of a number of teeth of the left ring gear, a number of teeth of the right ring gear, a number of teeth of the left planetary gear, and a number of teeth of the right planetary gear is a teeth number combination;
- the number of teeth of the right ring gear*the number of teeth of the left planetary gear/(the number of teeth of the left ring gear*the number of teeth of the right planetary gear) is a range specifying parameter;
- the number of planetary gear axes supported by the planet carrier is the number K of gear sets;
- for the range specifying parameter, each teeth number combination makes a value of the range specifying parameter be greater than 0.875, less than 1.142857, and not equal to 1.0;
- the number K of gear sets is an integer not less than two, and when the teeth number combination and the number of gear sets are set, a principle of matching the teeth number combination with the number of gear sets is:
- (1) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 2, setting the number of gear sets to 2;
- (2) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 3, setting the number of gear sets to 3;
- (3) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 4, setting the number of gear sets to 4 or 2;
- (4) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 5, setting the number of gear sets to 5;
- (5) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 6, setting the number of gear sets to 6, 3 or 2;
- (6) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 8, setting the number of gear sets to 8, 4 or 2;
- (7) when an absolute value of a difference between the number of teeth of the left ring gear and the number of teeth of the right ring gear is a multiple of 10, setting the number of gear sets to 5 or 2;
- the number of gear sets cannot be too large so as to avoid collisions between neighboring planetary gears;
- a rule for manufacturing and assembling planetary gears is:
- dividing the number of teeth of the left ring gear by the number K of gear sets to obtain a remainder, wherein a value of the remainder ranges from O to (K−1) and is an integer;
- during manufacturing of planetary gears, selecting an equiphase surface on a first planetary gear so that an equiphase angle value is a, selecting an equiphase surface on a second planetary gear so that the equiphase angle value is (a+1*2n*remainder value/K), selecting an equiphase surface on a third planetary gear so that the equiphase angle value is (a+2*2n*remainder value/K), sequentially manufacturing a fourth planetary gear, a fifth planetary gear, a sixth planetary gear, a seventh planetary gear and so on by analogy, and selecting an equiphase surface on a Kth planetary gear so that the equiphase angle value is (a+(K−1)*2n*remainder value/K);
- during assembly of planetary gears, the two ring gears and the planet carrier are assembled in place on the revolution axis, each mounting surface is calibrated, the equiphase surface of the first planetary gear with the equiphase angle value being a is caused to coincide with a first mounting surface, left and right equiphase points are caused to be outside the reference center distance, the first planetary gear is assembled, the equiphase surface of the second planetary gear with the equiphase angle value being (a+1*2n*remainder value/K) is caused to coincide with a second mounting surface, left and right equiphase points are caused to be outside the reference center distance, the second planetary gear is assembled, the equiphase surface of the third planetary gear with the equiphase angle value being (a+2*2n*remainder value/K) is caused to coincide with a third mounting surface, left and right equiphase points are caused to be outside the reference center distance, the third planetary gear is assembled, the fourth planetary gear, the fifth planetary gear, the sixth planetary gear, the seventh planetary gear and so on are assembled by analogy, the equiphase surface of the Kth planetary gear with the equiphase angle value being (a+(K−1)*2n*remainder value/K) is caused to coincide with a Kth mounting surface, left and right equiphase points are caused to be outside the reference center distance, and the Kth planetary gear is assembled;
- gear reference circle radii are:
- setting a reference circle radius of the left ring gear and a reference circle radius of the left planetary gear around the reference center distance, so that the number of teeth of the left ring gear I the number of teeth of the left planetary gear=the reference circle radius of the left ring gear/the reference circle radius of the left planetary gear, and that the reference circle radius of the left ring gear=the reference circle radius of the left planetary gear+the reference center distance, and setting a reference circle radius of the right ring gear and a reference circle radius of the right planetary gear around the reference center distance, so that the number of teeth of the right ring gear/the number of teeth of the right planetary gear=the reference circle radius of the right ring gear/the reference circle radius of the right planetary gear, and that the reference circle radius of the right ring gear=the reference circle radius of the right planetary gear+the reference center distance.