Mahindra 3535, Руководство по обслуживанию

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G-20 35 Series 4WD, Model - 3535, 4035, 4535 and 5035 SM June’08
Electrical System
Fig. 2
Electrical Circuit Diagram
Fig. 1
B. STARTER MOTOR
1. Introduction
Self Starter is used for cranking the engine.
The starter described here is pre-engaged type. This
starter is designated as ‘Pre-engaged’ since the drive
goes into complete mesh with the Ring gear before
the full power torque of the starter motor is developed.
The main feature being prevention of premature ejection
of the pinion by the flywheel during intermittent firing
pulses of the engine.
2. Description and Principle of Operation
The starter is 4-pole, 4 brush, earth return machine with
parallel connected field. Main parts are i) DE bracket
assy, ii) Drive assy, iii) Intermediate bracket assy, iv)
Armature assy, v) Solenoid switch assy, vi) yoke & field
coil assy, vii) commutator end bracket assy, viii) brush
gear assy. When the ignition switch is operated (refer
Fig. 2). The solenoid switch mounted on starter motor
gets energised and the plunger gets pulled. An actuating
lever whose top end is linked with the plunger, bottom
end is linked with the drive and centre is supported
on the eccentric pin, pushes the drive into mesh with
the flywheel ring gear when the solenoid is energised.
At the end of the travel of the plunger a pair of contacts
close connecting the starter to the battery directly, this
bye-passes the series winding (also called as operating
winding) of the solenoid Shunt winding (also called
hold-on winding) which is energised as long as ignition
switch is on holds the plunger in position. As soon as
the engine fires and the ignition switch is released, the
solenoid is released and supply to starter is cut off. This
also disengages the drive from the ring gear.
a. Drive Assembly
The drive assembly transmits the torque developed by
the armature to ring gear. The roller clutch arrangement
of the drive prevents armature from being rotated at
an excessively high speed in the event of pinion
remaining in mesh with the ring gear when the starter
is on. The clutch operates on the principle of wedging
of cylindrical rollers between two converging surfaces.
The convergent form is obtained by matching cam tracks
on a cylindrical surface. The clutch consists of 5 rollers
which run on cam track cut in inner member which is
driven by the armature. The pinion is an integral part
of the outer member.