Mahindra 3535, Руководство оператора

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35 Series-HST, Model - 3535, 4035, 4535 & 5035
50
Draft Control - Operation
Draft Control
As the draft of the implement varies due to irregularities of
ground contour, soil texture, or pitching of the tractor,
the load on the top link of the three point linkage will vary.
These changes are transferred through the internal
mechanism into hydraulic valve movement.
By means of the top link, the draft control system reacts not
only when the top link is in compression, as is usually the
case, when plowing, but also when the top link is in
tension, as with shallow working implements. An increase
in implement draft will increase the compression or reduce
the tension on the top link and the system will go to lift.
Conversely, a decrease in implement draft will cause the
system to go lower.
Due to setting of the draft control lever, the load required
to maintain the valve in the hold position is governed.
Therefore, the load the tractor has to pull is maintained
irrespective of ground contour, soil conditions, or the
pitching of the tractor.
The lever is moved Forward to deepen the implement and
Rearward to shallow it.
Setting the Draft Control
1. Move the PC lever (D) to its forward most position.
2. Move the position control stop screw (C) to the front of
the quadrant and lock it.
3. Lift the implement off the ground by pulling the PC
lever back to upper limit.
4. Lower the implement into work by moving the PC lever
to its forward most position. The faster the lever is
moved forward the quicker the implement will drop.
5. Move the tractor slowly in forward direction. When the
implement has reached the desired working depth,
move the draft control lever (A) rearward, until the
linkage begins to lift, due to the load on top link. This
will be the position of the lever for that particular depth
in a particular type of ground.
6. Having obtained a desired setting move DC Stop screw
(B) until it touches the DC lever (A) and lock it in this
position.
When the soil texture remains constant, the implement
weight is partially carried on the three point linkage.
Therefore, proportion of the implement weight is
transferred to the tractor rear wheels to improve traction.
When a condition arises which causes an increase in draft,
the system will lift and all the weight of the implement will
be transferred to the tractor rear wheels to provide
maximum traction. As soon as the draft returns to normal,
the system goes to lower position and the situation returns
to its former condition.
When the front wheels of the tractor drop into a furrow,
the tendency for the implements is to lift out of the
ground. As the implement lifts, the draft decreases and the
system goes lower to maintain the pre-set depth. If the rear
wheel drops into a furrow, the reverse will occur.
Thus under all operating conditions, the “Vary-Touch”
system provides maximum traction and constant implement
depth.
Do not transport or attach equipment when the
hydraulic system is in Draft Control. Use Position
Control for these operations. Always lower
hydraulic equipment to the ground before
stopping the Tractor.
Under No Circumstances must the Draft Control
Lever be used to Lift the implement to its
uppermost Position. To do so will cause
overheating of the system. All movements into
and out of the soil must be made by using the
Position Control lever.
Tractor Front
Tractor Front
B
A
C
D
C
B
A
D