Structure and Assembly of Genset Starter Motor
1. DC motor
The DC motor is the motive force of the output torque, and most of its structures use a four-pole series-excited motor. Such a motor has a large output torque at a low speed and a strong overload capability.
2. Clutch mechanism
The function of the clutch mechanism is to transmit the torque of the armature to the flywheel ring gear through the start gear, and the power of the motor is transmitted to the crankshaft to start the diesel engine. After starting, the motor is automatically separated from the diesel engine to protect the starter motor from damage. The clutch mechanism mainly has two types of spring type and friction type. Most of the starter clutch mechanisms of medium and small power diesel engines are spring-loaded, and the starters of high-power diesel engines mostly use friction plate clutch mechanisms.
3. Control switch
The electric starting system mainly has two kinds of electromagnetic and mechanical control switches, wherein the electromagnetic switch uses the electromagnetic suction to drive the fork to start.
Assembly and test method for starting motor of diesel generator set
I Start motor assembly
The assembly steps of the starter motor are exactly the opposite of the disassembly steps. Note the following when assembling:
1. Apply a small amount of grease to the friction parts of each bushing armature journal, key-way, etc. Do not miss out on the various gasket and assemble them in order.
2. When the outer casing is combined with the front and rear covers, locate the positioning holes and then assemble the two long bolts and tighten them.
3. When assembling the electromagnetic switch, the armature must be assembled according to the technical requirements. After the armature is assembled, it should be pulled by hand to determine whether it is fixed. After the armature lever and the fork are installed correctly, install the electromagnetic switch and tighten the two fixing screws.
4. Brushes with insulating sleeves shall be installed the insulated brush holder according to technical requirement.
5. After the starter motor is installed, when the drive gear is toggled with a screwdriver, it can be rotated flexibly without jamming. If the axial clearance of the armature is too small or too large, the thickness of the front and rear cover gasket of the shaft can be changed to adjust.
6. After the starter motor is assembled, check and adjust the clearance between the starter motor gear and the lock nut. During the inspection. The armature is pushed to the bottom. At this time, the gap between the drive gear and the lock nut should be in the range of 1.5-2.5 mm. When the gap value is too large, the drive gear cannot be completely combined with cover will be damaged. If the clearance value does not meet the technical requirements, the adjustments screw on the starter motor can be adjusted to meet the requirements. After adjustment, tighten the lock nut.
II starting motor test
After the starter motor is assembled, it should generally be tested on a diesel engine. When testing, it is necessary to use a battery with sufficient power. The test start motor should meet the following conditions:
1. When the diesel engine is started, the power to start the motor is sufficient, and there is no abnormal noise.
2. There should be no strong sparks at the brushes and commutators.
3. At start-up, the drive gear is not allowed to rotate at high speeds and the metal ringing of the gears hitting the flywheel ring gear.
Precautions for the use of diesel generator set starter motor
1. The continuous working time of the diesel engine should not exceed 10s every time, and the interval between the two starts should be more than 2min to prevent the armature coil from overheating and burning out. If the three times can not be successfully started, the cause should be found and then started.
2. When the drive gear is heard to rotate at a high speed and cannot mesh with the ring gear, the start button should be quickly released. After the starter stops working, the second start is performed again to prevent the drive gear and the flywheel ring gear from colliding with each other and being damaged.
3. When using generator sets for power supply in cold areas, use antifreeze oil. When starting, use a one screwdriver to pull the flywheel inspection hole for a few weeks before starting.
4. After the genset is started, its start button should be quickly released to return the drive gear to its original position.
5. During normal operation, it is strictly forbidden to press the diesel engine start button again.
6. Grease should be added to the front and rear cover bushings regularly to prevent dry friction from damaging the shaft and bushing.