LG PLANETARY TRANSMISSION
Product Description
Transmission System
Applicable Models and Main Parameters
Table 2-1
Transmission Model | A301 | A303 | A305 | A307A | A307B | BX50-02 | BX50-03 | ||
Applicable model | LG936LLG953 | LG936L LG944MSK | LG956L | LG946L LG952L LG952H | LG936L LG956L | LG953N | LG955N LG956N LFT20 | ||
Type of hydraulic torque converter | Single-stage four-element double-turbine hydraulic torque converter | ||||||||
Piston stroke in all gears (mm) | 1st gear | 1.4~2.8 | 1.7~3.5 | ||||||
2nd gear | 1.1~1.8 | 1.1~1.8 | |||||||
Reverse gear | 0.9~2.8 | 1.0~3.2 | |||||||
Transmission working pressure (MPa) | 1.1~1.5 | ||||||||
Inlet oil pressure of torque converter (MPa) | 0.5~0.6 | ||||||||
Outlet oil pressure of torque | 0.21~0.26 | ||||||||
Transmission type | Planetary power gearshift | ||||||||
Transmission gear | Two forward gears and one reverse gear | ||||||||
Quantity of 6#hydraulic transmission oil (L) | 44 | ||||||||
Transmission Overview
The planetary gear transmission (planetary transmission) consists of basic planetary gear row which accommodates planetary gears rotating axially, making the planetary transmission work with power gearshift only, characterized by force dispersion. Multiple planetary gears in the basic planetary gear row forming the transmission enable the load transmission by pairs of gears and thereby reduce the stress of each pair of meshing gears, permitting the use of small module gears and therefore reducing the gear volume. For this reason, the planetary transmission is compact in radial dimension.
| Fig. 2-1 | 1 Torque converter assembly 2 Ventilation cap 3 Lifting ring screw 4 Transmission return port 5 Oil suction pipe 6 Filler pipe 7 Oil outlet port of torque converter 8 Oil outlet port of transmission 9 Transmission pump 10 Steering pump interface 11 Brake 12 Front output flange 13 Case 14 Transmission control valve 15 Oil outlet port of torque converter 16 Rear output flange |
Structure and Principle of Transmission
Structure
The engine power is transmitted via the hydraulic torque converter to the power gearshift transmission composed of the planetary transmission part and the drive gear part. Its internal main structure is as shown in Fig. 2-2.
| Fig. 2-2 Structure of Planetary Transmission | 1 Primary input gear 2 Reverse gear friction lining 3 Isolated bracket assembly 4 1st gear friction lining 5 Reverse gear inner ring gear 6 1st gear piston 7 1st gear inner ring gear 8 1st gear planetary carrier 9 Intermediate output gear 10 Direct gear oil cylinder 11 Direct gear connecting panel 12 Direct gear piston 13 Direct gear pressure plate 14 Output shaft assembly 15 1st gear planetary shaft 16 Sun gear 17 1st gear oil cylinder 18 Reverse gear planetary carrier 19 Planetary gear 20 Reverse gear piston 21 Reverse gear planetary shaft 22 Outer ring gear 23 Intermediate input shaft 24 Inner ring cam 25 Secondary input gear |
The planetary transmission part consists of two planetary gear rows including the reverse gear planetary gear row (referred to below as reverse gear assembly) composed of planetary gear, reverse gear planetary carrier, reverse gear planetary shaft, retainer ring, washer, bolt, needle, stop washer and bearing, and the 1st gear planetary gear row (referred to below as 1st gear assembly) comprising the direct gear connecting panel, planetary gear, 1st gear planetary carrier, 1st gear planetary shaft, reverse gear inner ring gear, brake disc, retainer ring, needle, bearing, washer, bolt. Both rows have the same number of sun gears, planetary gears and ring gears. The direct gear assembly (2nd gear the same below) consists of the direct gear pressure plate, direct gear piston, direct gear oil cylinder, intermediate output gear, belleville spring, driving and driven friction linings of direct gear, direct gear shaft, bearing, retainer ring, seal ring, pin, rotary oil seal, washer, nut, etc.
The same sun gear is adopted in both rows for power transmission and splined to the intermediate input shaft and the direct gear input shaft, being the power input part.
The reverse gear inner ring gear, 1st gear planetary gear row, planetary carrier and direct gear pressure plate (fixed together with the intermediate output gear) are connected together through a spline tooth into a whole acting as the power take-off of the planetary transmission part.
The driving and driven friction linings of the reverse gear and the 1st gear are installed on the reverse gear planetary carrier and the inner ring gear respectively, connected to the driving friction lining through teeth. The driven friction lining is guided by the cylindrical pin fixed on the isolated bracket in the case and transfers the stress to the case. The driving and driven friction linings are compressed under the action of oil cylinder piston; when they separate from each other, the piston returns with the help of return spring arranged along the circumference.
There are two driving friction linings and one driven friction lining of the direct gear, and all of them are connected to the direct gear input shaft through bolts and nuts. There is only one direct gear driven friction lining which is guided by the cylindrical pin on the direct gear pressure plate and transfers the stress to the direct gear pressure plate. The clutch pushes and compresses the piston under oil pressure, and the piston returns with the help of belleville spring when the clutch disengages.