On the VAZ-21011 until 1980, a foot-operated windshield washer was installed, and on the VAZ-2101 and VAZ-2102 since 1980. This pump has an additional switch 5 of the windshield wiper. When you press the button, the liquid starts to spray, and then the windshield wiper turns on.
Since 1980, on the VAZ-21013 and VAZ-21011, instead of a foot-operated windshield washer, an electric-driven pump has been used, installed directly on the lid of the windshield washer fluid reservoir.
When the windshield wiper is in constant operation, the current flows from the "+" terminal of the battery 1 or the "30" terminal of the generator 8 through the armature winding of the electric motor 4, bypassing the windshield wiper relay 3. The electric motor operates at a constant speed, and the windshield wiper blades swing at a frequency of 50-60 cycles per minute.
When the windshield wiper switches to intermittent operation, the current flows from the generator terminal "30" through fuse block 6 to switch 2 and from it along the red wire to relay 3. Then along the yellow wire from relay 3 to switch 2 and along the white-black wire to ground.
In a relay, current flows through the electromagnet winding and causes the relay to operate. Upper relay contacts (on the diagram the left ones) open, and the lower contacts (on the diagram the right ones) close. The current flowing through the lower contacts of the relay goes through the blue wire to the electric motor and the latter begins to rotate.
When the relay is triggered, the current also flows through the breaker winding (the diagram shows on the right), which heats up. The bimetallic plate of the breaker bends from heating and opens the contacts of the breaker, disconnecting the power supply to the relay electromagnet winding. The lower contacts of the relay open, the current to the electric motor 4 is interrupted, and it stops.
Since the current no longer flows through the relay breaker winding, it cools down together with the bimetallic plate. The plate takes its previous shape and the breaker contacts close, turning on the power supply to the relay electromagnet winding. The described cycle is repeated again with a frequency of 9-17 times per minute.
During one cycle, the brush completes one double stroke and stops in the lower position. At the initial moment of switching on the windshield wiper for intermittent operation, while the bimetallic plate of the interrupter has not yet heated up, the brushes can make up to four continuous strokes.
The windshield wiper is switched off after the switch key or lever 2 is moved to the initial position. In this case, the current is supplied to the armature winding of the electric motor via the blue wire with a black stripe from the plug "B" of the fuse block through the contacts of the limit switch of the electric motor. At the moment when the windshield wiper blades come to the lower position, the projection of the cam of the worm gear of the reducer will open the contacts of the limit switch and disconnect the power supply to the armature winding. The armature of the electric motor will stop, and the windshield wiper blades will remain in the lower position.
Since 1985, windscreen wipers have been equipped with a reusable thermal bimetallic fuse. Its purpose is to protect the electric motor from overloads, for example, when the brushes freeze to the glass, etc.