Introduction of Doosan Excavator Transmission System(2)

            This article is about the detailed introduction of Doosan excavator transmission system (2)

 

When all transmission solenoid valves are de-energized(OFF)

the transmission is in "NEUTRAL".

Transmission solenoid valves(Y3 and Y5, Figure 24) are energized when in forward first gear.

Transmission solenoid valves(Y5 and Y6, Figure 25) are energized when in forward second gear.

Transmission solenoid valves(Y4 and Y5, Figure 26) are energized when in forward third gear.

Transmission solenoid valves (Y2 and Y4, Figure 27) are energized when in forward fourth gear.

Transmission solenoid valves (Y1 and Y3, Figure 28) are energized when in reverse first gear.

Transmission solenoid valves (Y1 and Y6, Figure 29) are energized when in reverse second gear.

 

Transmission solenoid valves(Y1 and Y4, Figure 30) are energized when in reverse third gear.

Downshift Overview

1. There are two downshit switches down Figure 31, and it is possible for operators to select one of them according to the condition.

2. If the downshift switch is depressed during the machine moving, downshifting takes place automatically. As a result, fast digging and moving is possible. But at the manual mode the kick-down can only be activated.

3. If a change or traveling direction takes place or the downshift switch is depressed a second time, downshifting is released automatically.

Kick-down:Forward Second Gear to Forward First Gear

(Auto Selector Switch "O"-Manual Mode)

With the auto selector switch (Figure 33) is in the "O"and the forward second gear is selected, if either downshift switch

(Figure 31) is activated,a pulse is sent to the "22"transmission controller. This signal energizes solenoid valves,(Y3 and Y5), which shifts the transmission to the forward first gear. When either switch (Figure 31) is selected a second time, the transmission pulse signal of the "22"terminal is interrupted and solenoid valve,Y5 and Y6, are energized and the transmis sion returns to the forward second gear.

Figure 34

When the auto selector switch (Figure 34) is in the I"position, the

"29"terminal of transmission controller is energized. This allows the transmission to automatically upshift and downshift gears depending on the load and on the engine speed.

If either downshift switch(Figure 31) is activated,a pulse signal is sent to the "22"terminal of transmission controller. This signal shifts the transmission to the next lowest gear.

When either downshift (Figure 31) is depressed a second time, the transmission pulse signal of the "22"is interrupted and the transmission returns to normal operation.

NOTE: The fourth to the third gear changes without any pm change when the downshift switch is pressed.

NOTE: The third to the second gear, and the third to the first gear, changes occur when the rpm is reduced200-

300 rpm from cument setting.

When the auto selector switch(Figure 35) is in the ""position, the "20"terminal of transmission controller is energized. This allows the transmission to automatically upshift and downshift gears depending on the load and on the engine speed.

If either downshift switch(Figure 31) is activated,a pulse signal is sent to the"22"terminal of transmission controller. This signal shifts the transmission to the next lowest gear.

When either downshift(Figure 31) is depressed a second time, the transmission pulse signal of the "22"is interrupted and the transmission returns to normal operation.

 

NOTE: The fourth to the third gear changes without any rpm change when the cdownshift switch is pressed.

NOTE: The third to the second gear, and the third to the first gear, changes occur when the rpm is reduced200-

300 rpm from cument seting.

LIS(Load lsolation System)-Optional Excessive bucket pitching is drastically reduced and good flotation is maintained for minimum operator fatigue and maximum productivity.

LIS is useful for sites where frequent cycles of loading and carry are needed or rough terrain.

When the LIS switch is "I"and the vehicle speed is above 8km/

h(4.97 MPH), the LIS solenoids valves(14) are energized and the LIS system is"ON".

When the LIS switch is "I"and the vehicle speed is below 6 km/h

(3.73 MPH) the LIS solenoids valves (14) are de-energized and the LIS system is' OFF".

NOTE: If the LIS switch is in the O' position, despite the vehicle speed the LUS solenoid valves (14)

de-energized and the LIS system is not operating.

AEB STARTER

Introduction

NOTE: To prevent the transmission ol temperature from faling down whie AEB operating, keep thetransmission ol temperature about 80℃ before starting AEB.(Temperature Range:60℃～

90℃)

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