7.7.4. Dismantling, assembly and check of technical condition of a motor-reducer of a cleaner

Fig. 7.28. Details of a motor-reducer of screenwash: 1 – persistent screw; 2 – thrust bearing; 3 – reducer gear wheel; 4 – panel; 5 – thermobimetallic safety lock; 6 – cover; 7 – cracker; 8 – electric motor case; 9 – anchor; 10 – brush holder; 11 – reducer case

For dismantling of a motor-reducer unscrew screws of fastening of a cover of 6 (fig. 7.28) of a reducer and remove it together with the panel 4 of the trailer switch. Then unscrew screws of fastening of the case 11 of a reducer to the case 8 of the electric motor and separate them. Take out an anchor of the 9th electric motor.
To remove a gear wheel 3 reducers, turn off a nut of fastening of a crank, remove a lock ring from an axis and take out from the case an axis with a gear wheel and washers.
After dismantling blow internal cavities of the electric motor compressed air for removal of deposits of coal dust and check a condition of brushes and a collector.
Brushes have to freely, without jammings to move in brush holders, and springs have to be whole and have sufficient elasticity. Smooth out a collector a fine-grained grinding skin, and then wipe with the pure rag which is slightly greased with technical vaseline. If the collector strongly burned or is worn-out, then replace a motor-reducer new better.
Check whether there are no jamming traces on anchor shaft necks. If necessary smooth out them a fine-grained grinding skin.
At assembly you take away brushes from a collector not to break them and not to damage their edges, and insert an anchor into the case with extra care, avoiding blows of an anchor about poles not to break them.
After assembly, for centering of bearings, knock with the wooden hammer on the motor-reducer case, and then check it at the stand.
At installation of a crank have it so that in final situation it was parallel to short draft of a cleaner and is directed towards the electric motor.
Data for check of a motor-reducer
Frequency of rotation of a shaft of a motor-reducer at the supply voltage of 14 V, the moment of load of 1,47 N · m (0,15 kgfs · l) and the ambient temperature of 25±10 °C, min.-1:
the first (small)       30–40
the second (big)       55–70
The consumed current at the loading moment stated above, And, no more:
at the first speed       3,5
at the second speed       5