Composition of Starter Ⅱ

1. Transmission device

1) Composition

The transmission device that realizes the meshing and separation of the driving gear and the flywheel gear ring in various starters is the same, and it is mainly composed of driving gear and a one-way clutch parts. The function of the transmission mechanism is to mesh the drive gear with the flywheel ring gear when starting and transmit the starter torque to the engine crankshaft.

The structure of the one-way clutch includes roller type, friction plate type, and spring type. It is mainly composed of driving gears, inner and outer raceways, rollers and springs, spline sleeves, fork sliding sleeves, and buffer springs. The inner and outer raceways form a wedge-shaped chamber. Rollers and springs are installed in them. To reduce the friction between the inner and outer raceways, grease is filled in the wedge-shaped chamber and sealed by the sheath. When maintaining the starter, do not put the one-way clutch in gasoline to clean it to avoid the loss of grease.

2) How it works

When the starter drives the crankshaft of the engine, the armature shaft is active and the flywheel is passive. The armature shaft first drives the outer race (outer raceway) of the one-way clutch to rotate clockwise (from the rear end of the engine) through the transmission parts conduit. Looking forward), and the drive gear meshing with the flywheel is in a static state. Under the push of friction and spring, the roller is on the narrower side of the wedge-shaped chamber, so that the outer race and the tail of the drive gear are clamped And combined into one, then the driving gear will rotate together and drive the flywheel to rotate so that the engine starts to work.

After starting the engine, the flywheel drives the drive gear to rotate, because the flywheel will drive the drive gear to rotate at a high speed, and the speed is much higher than the armature, so it can be considered that the flywheel is active and the armature shaft is passive, that is, the drive gear is active. Yes, the outer race is passive. In this case, the tail of the drive gear will drive the roller to overcome the spring force, so that the roller rolls to the wider side of the wedge-shaped chamber, so the roller has sliding friction between the tail of the drive gear and the outer race, and only the drive gear follows When the flywheel rotates, the power of the engine cannot be transmitted to the armature shaft, which plays the role of automatic separation. At this time, the armature shaft is only idling at its own speed, avoiding the danger of overspeeding.

2. Manipulation control device

The functions of the control device: one is to control the engagement and separation of the one-way clutch and the flywheel ring gear; the other is to control the connection and disconnection of the starter circuit. It usually consists of an electromagnet mechanism, motor switch, fork mechanism, and so on.

1) Electromagnet mechanism

Its role is to use electromagnetic force to operate the one-way clutch and control the motor switch. There are two coils wound around the copper sleeve. The thicker wire and the fewer turns are called the attracting coil, and the thinner wire and the more turns are called the holding coil. The two ends of the attracting coil are respectively connected to the electromagnetic switch terminal and the motor switch. Keep one end of the coil connected to the electromagnetic switch terminal, and the other end to the ground. A fixed iron core and a movable lead iron are installed in the copper sleeve. The tail of the lead iron is screwed with a connecting rod and connected to the upper end of the fork, so that when the coil is energized, the lead iron drives the fork to swing around its axis, and pushes out the one-way clutch to make it Mesh with the flywheel ring gear.

2). Motor switch

It is located in front of the electromagnet mechanism, and its casing is connected with the casing of the electromagnet mechanism. The two connecting posts of the motor switch are respectively connected with the battery and the magnetic field coil of the motor, and the inner end of the connecting posts is the fixed contact of the motor switch. When the electromagnet mechanism is energized, driven by the moving iron, the contact plate turns on the motor switch, and the motor is energized to run. When the starter is not working, under the action of the return spring, the contact plate and the contact are kept apart.