Abstract: A series of transmission gears use an internally meshing planetary gear structure. The structure has a first shaft, eccentric bodies provided on the first shaft, and external gears mounted on the eccentric bodies through bearings. An internal gear internally meshes with the external gears, and a second shaft is connected to the external gears through means for transmitting only the rotational component of the external gears. The series includes a group of sub-series of the transmission gears, including transmission gears which are different from each other in a speed change ratio within a range from a low speed change ratio to a high speed change ratio, and which are the same in the mating dimension for installation to a mating machine. The transmission gears in the same sub-series include a type of transmission gears of a low angular backlash type which do not reduce the angular backlash. Each type of transmission gear has a same speed change ratio, a same mating dimension, and a same transmission capacity.

Abstract: In a system for controlling a gear ratio of a multi-step geared or continuously variable automatic transmission of a vehicle, the gear ratio is determined through fuzzy production rules each having one of an ATF temperature, a steering or an engine coolant temperature. For example, the rule regarding the ATF temperature defines such that the gear position should be shifted down if the ATF temperature is high. With the arrangement, when the ATF temperature is high, the gear position is determined in the downshifting direction so that the amount of torque converter slippage can be reduced, whereby avoiding temperature rise in the transmission. And since the engine speed is relatively high at that situation, motive force could be sufficient even climbing a hill.

Abstract: An internally meshing planetary gear structure is the type having a first and second supporting blocks. The supporting blocks are rigidly connected to each other by carrier pins passing through inserting-fit holes formed on externally toothed gears. Also, the end surfaces of the carrier pins are exposed on a counter-member mounting surface of the first supporting block positioned on the counter-member side, and thus screw holes for screwing counter-member fixing bolts are formed on the end surfaces. With this arrangement, it is possible to enlarge the actual usable area of a counter-member mounting surface of the first supporting block and hence to increase the number of counter-member fixing bolts.

Abstract: An inscribed meshing speed increasing and reduction gear construction in which external teeth (for example, a1 and a2, b1 and b2, and c1 and c2) cut at the same position during processing are not simultaneously meshed with (outer pins 111 of) internal-tooth gear during operation in order to improve the accuracy after completion of assembling even if the gear is cut by a machine of similar processing accuracy. Thereby, (although it seems to be contrary to a conventional idea that said external teeth cut at the same position should be simultaneously meshed with the internal-tooth gear), the actual accuracy after completion of assembling can be improved. In this case, when both the number of teeth (24 in FIG. 1) of external-tooth gears 105a and 105b, and a difference in the number of teeth (4 in FIG. 4) between the external-tooth gear and (outer pins 111) internal-tooth gear, are set to integer times of the number (2 in FIG.

Abstract: A planetary gear system comprises a plurality of external gears swingably rotated by at least three eccentric members juxtaposed axially with their phases offset from each other; an internal gear internally meshing with these external gears; and a flange for retaining pins fitted with a play in internal pin holes formed in the external gears. This planetary gear system is used as a planetary reduction gear when the eccentric members are rotatively driven with either one of the internal gear or the flange being held stationary, so as to obtain an output of reduced rotation, or as a planetary overdrive gear in which either one of the internal gear or the flange is held stationary, and an input is applied to the other to obtain an output of accelerated rotation from a shaft on which the eccentric members are installed. All the eccentric members are formed integrally as one component.