10.3.1. Generator


Fig. 9.58. Generator: 1 — a generator casing; 2 — tension regulator with brushes; 3 — a bolt + conclusions; 4 — the condenser; 5 — a back cover of the generator; 6 — the bearing plug; 7 — contact rings; 8 — the persistent plug; 9 — a rotor winding; 10 — rotor poles; 11 — the fan; 12 — a generator shaft; 13 — a forward cover of the generator with the bearing; 14 — the plug; 15 — a pulley; 16 — a washer; 17 — the plug of the forward bearing; 18 — a stator winding; 19 — the back bearing; 20 — the stator; 21 — the diode of the vypryamitelny block; 22 — the vypryamitelny block; 23 — latches




The generator 9422.3701 — the three-phase synchronous electrical machine with electromagnetic excitement with the built-in vypryamitelny block and the regulator of tension. The device of the generator is shown in fig. 9.58.

Fig. 9.59. Electric circuit of the generator: 1 — the generator; 2 — tension regulator; 3 — a brush; 4 — a ring contact; 5 — an excitement winding; 6 — stator windings; 7 — the condenser; 8 — excitement winding diodes; 9 — power diodes




Internal parts and windings of the generator are cooled with air which is blown through windows in back and forward covers by means of two centrifugal fans 11 installed on a shaft of a rotor. In fig. 9.59 the electric circuit of the generator is shown.
The generator is given to rotation by means of a poliklinovy belt from a pulley of a bent shaft of the engine. The rotating magnetic field which is formed in the presence of current in an excitement winding crosses stator windings, induces in them alternating electric current. Alternating current will be transformed in the vypryamitelny block in constant and further arrives to consumers.
The generator works in common with the built-in electronic regulator of tension Ya212A11E. The regulator supports generator tension in the set limits.
Technical characteristics of the generator
The direction of rotation (from a pulley)..... right
Tension (nominal), In..... 14
Maximum current, And..... 72
Frequency of rotation of the generator with which there is an excitement of the generator at a temperature of air and the generator of +25 °C no more, mines-1..... 1400
Rotation frequency with which the generator has to give current:
40 And no more, mines-1..... 1800
70A no more, mines-1..... 5000
The adjustable tension of the generator at +25 °C and change of current of loading from 5 to 65 And with a frequency of rotation of a rotor of 5000 min.-1, In..... 13,5 — 14,2
Excitement winding resistance at +25 °C, Ohm..... 2,3 — 2,7
Type of brushes..... M1
Pressing of springs brushes, kgf..... 0,18 — 0,25
Bearings are ball:
in a forward cover..... 6180302U2S24
in a back cover..... B5-80202KT2Sh2US24
Vypryamitelny block..... BVO1-105
Number of restrictive power diodes..... 6
Number of auxiliary diodes..... 3
Maintenance of the generator
At maintenance it is necessary to make check of fastening of the generator and arms of the generator, if necessary to tighten.
To make check of the regulator of tension and brush knot of the generator:
- to remove tension regulator with brush knot from the generator.
To clear brushes of dust and dirt, to check height of brushes and ease of their movement under the influence of brush springs. At a vystupaniye of brushes tension regulator with brushes or brushes to replace less than 4,5 mm.
If necessary to check adjustable tension (see. "Repair of the generator").
To wipe with gasoline contact rings. In case of their wear or a podgoraniye to smooth out or pierce as directed the section "Repair of the Generator".
Repair of the generator
For removal of the generator:
1. To disconnect the rechargeable battery from onboard network of the car.
2. To disconnect wires from the generator.
3. By means of the tension device to weaken a tension of a driving belt and to remove it.
4. To turn off two bolts of fastening of the generator to arms and to remove the generator.
For installation of the generator:
1. To establish two bolts of fastening of the generator to arms.
2. If it is necessary to install the new generator on the engine, then it is previously necessary to release a coupling bolt of a back eye of the top arm. In a back eye to install the plug and previously to establish the top bolt with a small inhaling of fastening of the generator to an arm. Then to fix the generator to the lower arm. To finally fix the top bolt and to tighten a coupling bolt of a back eye of the top arm.
3. To make a final inhaling of bolts of fastening of the generator.
When dismantling the generator which is subject to repair:
- to remove the protection cover 1 (see fig. 9.58);
- to remove tension regulator with the brush holder and brushes 2, to disconnect a wire from tension regulator;
- to unscrew four coupling screws of the generator and to remove a back cover 7 with the stator 20;
- to disconnect the phase ends of a winding of the stator from the vypryamitelny block 22, to remove the stator;
- if necessary to remove the vypryamitelny block;
- if necessary to remove a pulley from a rotor shaft;
- if necessary to remove from a rotor shaft a forward cover 13 together with the bearing.

Fig. 9.60. The scheme of a control lamp with the rechargeable battery: 1 — the rechargeable battery; 2 — the 1 — 5 W control lamp; 3 — the probe




Control of details of the generator should be made a control lamp (see fig. 9.60) or the E236 device.
Regulator of tension and brush knot
Brushes have to be whole, without chips and other defects; brushes have to move freely in channels of the brush holder under the influence of springs. The brushes which are worn out up to the height of vystupaniye of 4,5 mm are subject to replacement together with tension regulator. It is necessary to check effort of springs of brushes for what the end of one brush acting from the brush holder to press on a cup of scales. When the brush acts from the brush holder on 2 mm, to notice the indication of scales which has to be 180 — 260 гс. To repeat the same with the second brush.

Fig. 9.61. Scheme of check of serviceability of the regulator of tension: 1 — the 21 — 35 W control lamp, 2 — the rechargeable battery, 3 — tension regulator, 4 — brushes




To collect the scheme shown in fig. 9.61 for check of serviceability of the regulator of tension. 1 to connect conclusions from a lamp to different brushes. At the serviceable regulator of tension the control lamp has to burn.

Fig. 9.62. Scheme of check of size of adjustable tension: 1 — the 21 — 35 W control lamp; 2 — an adjustable source of a direct current; 3 — the control voltmeter; 4 — tension regulator; 5 — brushes




For check of adjustable tension it is necessary to collect the scheme shown in fig. 9.62.
1 to connect conclusions from a lamp to different brushes. To establish tension of a source of 12 V, the lamp has to burn. Increasing tension of a source 2, to establish at what tension the lamp 1 will go out. It will also be adjustable tension tension regulator. It has to be within 13,5 — 14,2 Century. If tension does not keep within the specified limits, the regulator of tension is subject to replacement.
Stator

Fig. 9.63. Check on lack of short circuit of coils of the stator on the case




Fig. 9.64. Check of windings of the stator on break of a chain




At the stator to check lack of short circuit of its windings for the case. For this purpose it is necessary one tip from a control lamp (see fig. 9.60) to connect to the case, and another serially to concern one of three conclusions of a winding (see fig. 9.64). 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. Then it is necessary to check integrity 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 (see fig. 9.64). 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 vitkovy short circuits by means of an ohmmeter. On poles of the stator there should not be rotor zadevaniye traces for them. In the presence of zadevaniye to check the plastic holder of the bearing; if necessary to replace it.
To be convinced that the bearing on a cover from a pulley sits densely.
Rotor

Fig. 9.65. Check of resistance of a winding of excitement of a rotor




Fig. 9.66. Check of a rotor on lack of short circuit of a winding of excitement on the case




The rotor of the generator needs to be checked for lack of vitkovy short circuits by means of an ohmmeter (see fig. 9.65), attaching its tips to contact rings. By means of a control lamp to check for lack of short circuits of a winding of excitement on the case. For this purpose to connect a tip to the rotor case, and another serially to concern one of two contact rings (see fig. 9.66). In the presence of damages the rotor is subject to replacement. If at survey of contact rings of a rotor it is revealed that they are polluted and have traces of a podgoraniye and uneven wear on width, to smooth out it a small skin granularity 80 or 100. For cleaning of rings it is necessary to fix a rotor for a flange of a forward cover in a vice, smoothly turning a rotor, to make cleaning of rings a skin.
If rings have strong wear and a beating of a surface, they should be pierced on the lathe. The roughness of rings after processing has to have the Ra 1,25 parameter. Minimum admissible diameter of a pro-point of contact rings of 12,603 mm. After a pro-point to check the indicator a beating of contact rings. The beating of rings leads more than 0,08 mm to a bystry podgoraniye of rings and wear of brushes, especially at high turns of the engine. Bearings of a rotor have to rotate easily without jammings and big side plays (no more than 0,25 mm).
Vypryamitelny block

Fig. 9.67. Electric circuit of the vypryamitelny block: 1 — the diode power (positive polarity); 2 — a plate assembly (negative); 3 — a plate assembly (positive); 4 — a conclusion of diodes of a winding of excitement; 5 — the excitement winding diode; 6 — the diode of power negative polarity




Fig. 9.68. Electric circuit of check of diodes: 1 — the diode; 2 — a control lamp; 3 — 21 W; 3 — the rechargeable battery of 12 V




The Vypryamitelny block (fig. 9.67) needs to be cleared of dirt carefully. To make check of diodes by means of a control lamp (fig. 9.68). As in each section of the block diodes of various polarity are mounted, check them at various polarity of turning on of the rechargeable battery.
At turning on of the checked diode according to the scheme A the lamp has to burn, and at inclusion according to the scheme B should not burn. If the specified condition is not satisfied, it is necessary to replace the vypryamitelny block.
More careful check of diodes should be done by means of devices for check of semiconductor devices. After the end of survey and replacement of defective parts, the generator should be assembled.
Assembly of the generator


Fig. 9.69. The electric circuit of check of the generator at the stand: 1 — a tachometer; 2 — the generator; 3 — the ampermeter on 100 A; 4 and 7 — switches; 5 — a rheostat on 70 A; 6 — the rechargeable battery; 8 — the voltmeter on 30 V; 9 — the 3 — 4 W control lamp; 10 — the drive electric motor




Assembly of the generator is made as it should be, the return to dismantling. After assembly the generator needs to be checked.
Serviceability of the generator and correctness of its assembly is determined by check by the frequency of rotation of a rotor at which the generator begins to give current in 40 A and 70 A. Check is made at the test bench consisting of the electric motor which is smoothly changing the frequency of rotation of a rotor of the generator up to 5000 min.-1, the voltmeter, the ampermeter, the rheostat creating loading to 70 A in a chain of the generator and rechargeable battery (see fig. 9.69).
For check of serviceability of the generator it is necessary to turn on the switch 7, at the same time the control lamp 9 has to light up. To finish the frequency of rotation of the generator up to 1500 min.-1, the voltmeter 8 has to show tension 13B. The control lamp 9 has to go out. To increase the frequency of rotation of the generator up to 1800 min.-1 and to turn on the switch 4. 5 to establish by Reostatat on the ampermeter 3 loading 40 A. To increase the frequency of rotation of the generator up to 5000 min.-1 and to establish by means of a rheostat the 5th loading 70 A. The voltmeter 8 has to show tension of 13,5 — 14,2 Century.
The serviceable generator with the regulator of tension has to satisfy to the above-stated parameters. The specified inspection can be carried out at the E242 stand.