Fig. 9.2. Generator: 1 — a bearing cover; 2 — a brush holder cover; 3 — the brush holder; 4 — the condenser; 5 — a brush; 6, 13 — covers; 7 — the vypryamitelny block; 8 — the stator; 9 — a contact ring; 10 — a rotor; 11 — an excitement winding; 12 — the ball bearing; 14 — the fan; 15 — a pulley

Fig. 9.3. Electric circuit of the generator: 1 — a contact ring; 2 — a brush; 3 — an excitement winding; 4 — a stator winding; 5 — a heat sink plate; 6 — the diode; 7 — the condenser

The generator 161.3701 * (fig. 9.2, 9.3) represents the three-phase synchronous electrical machine with electromagnetic excitement and the built-in silicon rectifier. The generator works together with tension regulator.

Begin survey of the generator with brushes of the brush holder and contact rings. It is necessary to be convinced that brushes are whole, do not jam in brush holders and reliably adjoin to contact rings, to check pressing of springs brushes. The brushes which are worn out to 8 mm are subject to replacement.

Fig. 9.4. Check of effort of springs of brushes

For measurement of pressing of springs brushes to remove one brush, to install a cover in the brush holder and to hold it a hand. The end of a brush acting from the brush holder to press on a cup of arrow scales (fig. 9.4). When the brush acts from the brush holder on 2 mm, notice indications of scales. To repeat the same with the second brush.

To blow the generator compressed air. To wipe the brush holder of a brush and slightly polluted contact rings with the pure napkin moistened in gasoline.

Strongly polluted contact rings with a small podgoraniye and small roughnesses should be smoothed out (having removed the brush holder) glass paper granularity 80 or 100, rotating an anchor a hand. It is forbidden to apply for this purpose an emery cloth. Worn out, burned slightly or having the raised beating of a ring pierce on the lathe.

For removal of the generator:

— to disconnect the rechargeable battery from onboard network of the car;

- to disconnect wires from the generator;

- to remove a tension level of the generator;

- to turn the generator towards the block of cylinders of the engine and to take off a driving belt;

- to turn off bolts of fastening of the generator and to remove the generator.

Dismantling. To disassemble the generator in the following order:

- to remove the brush holder with brushes;

- to uncover the bearing;

— to unscrew coupling screws of the generator and to remove a back cover with the stator;

- to disconnect the phase ends of a winding of the stator from the vypryamitelny block and to remove the stator;

- to remove a pulley, the fan, a spline and the persistent plug from an anchor;

Fig. 9.5. Removal of a forward cover of the generator

- to remove from a rotor shaft a forward cover together with the bearing, using carving openings in a cover and special adaptation (fig. 9.5).

Fig. 9.6. Check on lack of short circuit of coils of the stator on the case

By means of the control lamp included in the alternating current main (fig. 9.6) to check lack of short circuit of coils of the stator for the case. When checking by a control lamp to connect it to any conclusion of a winding of the stator and the case. At the same time tips should not concern the case. The lamp should not burn. If the lamp burns, it indicates short circuit of a winding of the stator on the case. In this case it is necessary to eliminate damage or to replace the stator.

Fig. 9.7. Check of windings of the stator on break of a chain

Then it is necessary to check serviceability of windings of the stator. For this purpose the control lamp is serially connected to two tips of conclusions of a winding of the stator (fig. 9.7), at a serviceable winding the lamp has to burn. If between any two conclusions the lamp does not burn, it indicates break of a winding or violation of connection in an average point of phases.

Stator windings also should be checked for lack of mezhvitkovy short circuits. Windings should not move in grooves that can lead to a mastication of isolation and mezhvitkovy short circuit.

On the internal diameter of the stator there have to be no rotor zadevaniye traces. In the presence of zadevaniye to check covers and bearings; if necessary to replace them.

At survey to pay attention to absence of damage of covers, especially in the locations of paws of fastening.

Diameter of an opening under the bearing in a cover from contact rings has to be (35±0,012) mm. If diameter of an opening under the bearing stated above, then a cover is subject to replacement.

Make sure that the bearing in a cover from a pulley sits densely (press landing). Diameter of an opening under the bearing has to be 47+0,027mm.

Fig. 9.8. Check of resistance of a winding of excitement of a rotor

Fig. 9.9. Check of a rotor on lack of short circuit of a winding on the case

It is necessary to check by means of an ohmmeter (fig. 9.8) resistance of a winding of excitement of a rotor which has to be 2,35 — 2,6 Ohms at 20 °C, and also on lack of short circuits of a winding on the case (fig. 9.9). In the presence of damages the rotor is subject to replacement.

Fig. 9.10. Cleaning of contact rings

If at survey of contact rings of a rotor it is revealed that they are polluted and have traces of a podgar and uneven wear on width, rings should be smoothed out a small glass skin granularity 80 or 100. For cleaning of rings it is necessary to fix a forward cover in a vice and smoothly turning a rotor, to make cleaning of rings a skin, as shown in fig. 9.10.

Fig. 9.11. Check of a beating of contact rings

If rings have considerable wear and the raised surface beating, they should be pierced on the lathe. The roughness of the processed surface of rings has to be no more Ra = 0,8. Minimum admissible diameter of a pro-point of contact rings of 29,2 mm. After a pro-point the beating of rings (fig. 9.11) is necessary провернть an idikator. The beating of rings gives 0,08 mm to their bystry podgoraniye and wear of brushes above.

To check whether jam a brush in brush holders, and also a state and size of wear of brushes and force of pressing of springs of brushes. By weak pressing of brushes sparking increases and rings burn. Excessive pressing of brushes causes their increased wear. Pressing has to be within 1,9 — 2,5 N (0,19 — 0,25 kg · с). It is necessary to watch that brushes in brush holders moved freely, without jammings and the increased gap. Even insignificant jamming of brushes which is sometimes difficult for defining increases sparking under brushes.

The brushes which are worn out up to the height of 8 mm or damaged should be replaced new the M1A type. It is impossible to apply brushes of other type. Carefully clear greasy brushes and blow compressed air.

Fig. 9.12. Vypryamitelny block: 1 — a positive plate of the heat sink; 2 — the diode with positive polarity on the case; 3 — the diode with negative polarity on the case; 4 — a negative plate of the heat sink

Fig. 9.13. Check of the diode by means of a control lamp: 1 — the diode; 2 — a control lamp; 3 — a source of a direct current of 6 — 12 V

The BPV 46-65-02 or BPV 34-65-02 Vypryamitelny block (fig. 9.12) needs to be cleared of dirt carefully. To make check of diodes a control lamp or an ohmmeter. When checking it is necessary to consider that in tires diodes of various polarity are pressed. At turning on of the checked diode according to the scheme A (fig. 9.13) the lamp has to burn, and at inclusion according to the scheme B should not burn. If the specified condition is not satisfied, the vypryamitelny block is subject to replacement.

More careful inspection of diodes should be carried out by means of the special device for check of semiconductor devices. After the end of survey and replacement of defective parts the generator should be assembled. Collecting the generator is made as it should be, the return to dismantling. After assembly it is necessary to make control check of the generator.

Control check is made at the test bench consisting of the electric motor allowing to change smoothly the frequency of rotation of the generator up to 3000 ^min.-1 devices; the resistor allowing to create loading to 50 A in a chain of the generator, battery 6CT-55A and resistor in an excitement winding chain on 5 A. It is possible to use the control and measuring E242 stand.

Fig. 9.14. The scheme of check of the generator at the stand: 1 — a tachometer; 2 — the electric motor; 3 — the generator; 4, 8 — the voltmeter; 5 — the index of current; 6, 10 — switches; 7,9 — load resistors; 11 — the rechargeable battery

The scheme of connection of the generator for test at the elementary stand is shown in fig. 9.14. For check of the generator it is necessary to include the scheme the switch 10 and the resistor 9 to adjust tension of 14 Century on the voltmeter. Without loading (the switch 6 is switched off) when the generator cold, the voltmeter 4 has to show 14 V with a frequency of rotation of a rotor no more than 950 ^min.-1. Then it is necessary to include the scheme the switch 6 and, increasing the frequency of rotation of the generator, to increase loading. At loading 50 A and voltage of 14 V (voltmeter 4) the frequency of rotation of a rotor has to be no more than 2100 ^min.-1. During these tests to support tension on conclusion "Ш" by the resistor 9 within 14 V (voltmeter 8).

It is necessary for installation of the generator:

- to turn off nuts of fastening of arms of the generator to the block of cylinders;

- to install the generator and previously to fix a forward bolt of fastening. Movement of a forward arm to achieve coaxiality of a pulley of the generator with pulleys of a bent shaft and the water pump;

- movement of a back arm to achieve that between a paw of the generator and an arm there was no gap;

- to establish a back bolt and to tighten a little it; to fix nuts of fastening of arms to the block;

- to establish a belt and to make its tension by means of a tension level;

- to make a final inhaling of bolts of fastening of the generator.