Description
Product details
0501216209 DW-3 4WG200 transmission controller gear selector suitable for LG958L LG968 LG959 CLG856 ZL50GN and other 5t wheel loaders
Package List: gear selector
Applied Model: Gear selector is suitable for LG958L LG968 LG959 CLG856 ZL50GN and other 5t wheel loaders
Part Number: 0501216209
2.1.4 Introduction to KD Key Functions (4WG158/200)
(1) KD (Kick-Down) function, namely the low gear shift function.
There is one button at the end of DW-2 gearshift handle, which is the KD key, and it can be
used to decrease the vehicle speed to the first forward gear from the second forward gear.
(2) Brake power cutoff function of the first gear and the second gear.
In the electric control system, two pressure cutoff switches (one is the service brake pressure
switch and one is the emergency/parking brake pressure switch) can be connected. When the
driver steps down the foot brake pedal for brake; due to interaction between the brake pressure and the service brake pressure switch, the pressure switch will turn on the power circuit and the computer (namely the electric control box) circuit (equivalent to one electric signal of the computer), and then the computer will command the transmission control valve to act and cut off the pressure oil passage of the transmission clutch, namely the transmission power from the engine. In such case, all power of the engine will be transmitted to the working pump of the loader. Accordingly, when the first and second gears work, the working hydraulic system of the loader will have more sufficient power to perform excavation operation, thus improving the working efficiency of the working device.
In addition, when pressing down the emergency/parking brake button, the emergency/parking brake pressure switch will also act; the pressure switch will turn on the power circuit and the computer circuit, and then the computer will command the transmission control valve to act (namely the transmission power from the engine will be cut off in case of emergency brake), thus improving the brake effect.
(3) Neutral gear locking function and neutral gear start interlock function for vehicle safety
improvement. The gear control handle DW—3 is designed and installed at the lower left part of the steering wheel; if rotating the handle, the speed can be changed to the first, second, third and fourth gears, as shown in Figure 2-13. If pushing the control handle forwards, the vehicle will be driven forwards; if pushing the control handle backwards, the vehicle will be driven backwards; if the control handle stays at the neutral gear, the vehicle will keep still
Figure 2-13 Gear Control Handle of 4WG200 Transmission The neutral gear safety lock is used to avoid vehicle movement due to misoperation. When turning the safety lock to position “D”, the vehicle gear will be engaged for traveling; when turning the safety lock to position “N”, the vehicle will be locked at the neutral gear. If engaging the neutral gear and rotating the locking button of the neutral gear safety lock of the gearshift handle to the locking position (at position “N”), the vehicle will be locked at the neutral gear to avoid gear engagement due to misoperation.
The engine can be started if engaging the neutral gear. When engaging the neutral gear and
opening the electric lock, the gearshift handle will send an electric signal to the start interlock
relay, and then the start circuit will be connected; or else, the engine can’t be started.
(4) Working process of KD key of ZF transmission
With KD function (namely the forced low gear shift function), the loader working efficiency
can be greatly enhanced. During operation, the loader will be started at the second gear and
then driven at the third gear; when approaching to sand and stone material piles, the second
gear will be engaged. In case of material excavation, if pressing down KD key (without rotating
the gearshift handle), the vehicle speed will be automatically reduced to the first gear. When the bucket is full, pull the gearshift handle backwards to the reverse gear, and the vehicle can be automatically turned to the second reverse gear from the first forward gear.
When being driven backwards to a proper position, push the gearshift handle forwards to the
forward gear and change speed according to following process: 2R → 2F → 3F → 2F. Before
being driven to the dump truck and discharging materials onto the dump truck, change speed
according to following process: 2F → 2R → 3R → 2R, and then the loader will return to the
start point. KD function will be released after rotating the gearshift handle.
In case of material excavation, it is unnecessary to rotate the loader handle to select the speed
gear, just perform operation according to steps shown in Figure 2-14:
