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Pic. 34. Windshield Wiper: 1. Crank; 2. Rubber bushings; 3. Cleaner drive bracket; 4. Cleaner motor reducer; 5. Intermediate lever; 6. Leash; 7. Axis; 8. Insert; 9. Lock washer; 10. The axis of the lever; 11. Lever axis bushing; 12. Lining; 13. Wind window frame panel; 14. Lever axle fitting; 15. Cap; 16. Brush lever; 17. Lever stem; 18. The base of the lever; 19. Anchor shaft; 20. Gear reducer; 21. Adjusting screw; 22. Thermal bimetallic fuse; 23. Spring plate limit switch; 24. Lid; 25. Panel; 26. Cam; 27. Gearcase cover; 28. Pinion axle bushing; 29. Gear axle; 30. Ball bearing armature shaft; 31. Armature winding; 32. Anchor core; 33. Bushing of the rear end of the armature shaft; 34. Thrust bearing; 35. Hull; 36. Permanent magnet; 37. Collector; 38. Brush holder; 39. Washer pump motor; 40. Electromagnetic windshield washer valve; 41. Mounting block; 42. Ignition switch; 43. Switch cleaners and washer glass; 44. Windshield wiper relay; I. Scheme of switching on the 1st and 2nd speed of the cleaner; II. Scheme for switching on the intermittent operation of the wiper and washer of the windshield; A. 1st (small) cleaner speed; B. 2nd (big) cleaner speed; C. Intermittent operation, D. Washer on.
Device
Electric windshield wiper with parallel brush movement. It has two constant modes of operation, but with different brush speeds, and one mode with intermittent operation. The cleaner consists of a geared motor (electric motor with gearbox) 4, crank mechanism and brushes with levers. The dimensions of the parts of the mechanism are chosen so that the swing angle of the leashes is about 85°.
The levers 5 are connected to the leashes by the bis crank 1 with spherical hinges, which allow the mechanism to work reliably with some non-parallelism of the axes of the leashes. The hinges contain two hemispherical ceramic-metal inserts 8 impregnated with oil, which also fills the space between the inserts. The inserts are unclenched from the inside by a spring.
DC three-brush, two-pole electric motor with excitation from permanent magnets with two speeds of rotation. It has a stamped steel case 35, inside which two permanent magnets 36, having the shape of half rings, are fixed with spring holders riveted to the walls of the case. These magnets, together with the housing, form the stator of the electric motor.
The armature of the electric motor consists of a shaft 19, a core 32 and a collector 37. In the grooves of the core, insulated with cardboard, the winding 31 of the armature is laid, the conclusions of the sections of which are soldered to the copper plates of the collector 37. The armature shaft rotates in a ball bearing 30 and a ceramic-metal bushing 33. The outer surface of the bushing spherical, which allows it to rotate in the nest of the housing and self-align along the axis of the armature shaft. A felt ring is placed around the sleeve. The sleeve and felt are impregnated with oil. Bearing 30 is also filled with grease. Therefore, lubrication of the motor during maintenance is not required.
The body of the electric motor is closed by cover 27, which is also the crankcase of the gearbox. The gearbox ratio is 74:1. The crankcase is closed with a plastic panel 25 and a cover 24. The panel contains contact racks to which wires are soldered and a spring plate 23 is attached with switch contacts that stop the motor when the brushes are in the lower position. Under the action of elasticity, the plate 23 is pressed against the upper (on the image) rack. When the protrusion of the cam 26 is against the plate, it presses it from the upper column and closes with the lower column.
To protect the electric motor from overloads when the brushes freeze to the glass, there is a high resistance to their movement, or when the wiper mechanism jams, a reusable thermal bimetallic fuse is installed in the cleaner.
Two speeds of rotation of the motor shaft are achieved through the use of three brushes to supply voltage to the armature winding. 1st speed (small) is provided by supplying voltage to the brush located in the geometric neutral of the electric motor. When the supply voltage is applied to the brush displaced from the geometric neutral, the motor armature rotates from the 2nd (greater) speed.
Windshield wiper relay. Relay 44 type 52.3747 is designed to create an intermittent operation of the windshield wiper. The relay is installed in the mounting block 41 and consists of an electronic control circuit and an executive electromagnetic relay.
The relay ensures that the cleaner is turned on approximately 14 times per minute. In addition, when the windshield washer is turned on, the relay turns on the 1st speed of the wiper if it was turned off or worked in intermittent mode. After the windshield washer is turned off, the relay delays turning off the wiper until it performs another 2-4 full cycles of cleaning the glass with brushes.
The work of the purifier
1st speed. Contacts close in this mode "53a" And "53" switch. The current goes to the cleaner motor in the following way: contact "53" switch, gray wire, through the mounting block to the brush of the electric motor, located in geometric neutral, and then to "mass".
2nd speed. This mode is obtained by closing contacts "53a" And "53c" switch. Current comes from the contact "53c" through a gray wire with an orange stripe through the mounting block to the brush of the electric motor, offset from the geometric neutral, and then to "mass".
Intermittent operation, provided when the contacts are closed "53a-j" And "53-53s" switch. From contact "j" switch voltage is supplied to the output "1" relay 44. The electromagnetic relay is activated and the contacts close "15" And "S". Current comes from the output "15" relay on "S", then to closed contacts "53-53s" switch and through the gray wires to the motor brush. In this case, the relay turns off and on again at a frequency of 14 cycles per minute, creating intermittent operation of the cleaner.
Turn off the purifier. The switch lever 43 is moved to its original position, in which the contacts are closed "53-53s". At the same time, the outputs of the relay are closed "31 in" And "S". Spring plate 23 is pressed against the right column (on the image) limit switch. The current supplying the armature winding of the electric motor goes from the fuse 22, through the plate 23 to the output "31 in" relay, then from the output "S" relay for closed contacts "53e-53" switch and, further, through the gray wires to the brush "A" electric motor. The cleaner operates at low speed until the cam 26 presses the plate 23 from the right rack and closes it with the left (on the image) rack. At this point, the cleaner will stop and its brushes will remain in the down position.
Switching on the windshield washer. Contacts close "W" And "53ah" switch, and the current comes from closed contacts "30" And "15/2" ignition switch via fuse "4" mounting block for closed contacts "53ah" And "W" switch. Then, through the pink wire, the current goes to the mounting block and from it to the electric motor 39 of the washer pump to the windshield washer valve 40. The valve opens and the washer pump delivers windshield washer fluid.
At the same time, voltage is applied to the output "86" relay. It works, and conclusions "31 in" And "S" close. Since when the cleaner is turned off, the contacts "53rd" And "53" switch are closed, then current begins to flow through the circuit: from fuse 22 to the terminals "31 in" And "S" relay, then to contacts "53rd" And "53" switch and from them to the motor brush. Thus, when you turn on the windshield washer, the cleaner starts working from the 1st (small) speed.