Whenever operative a vehicle, it is necessary to determine its speed. For this purpose, a device known as a speedometer, is used. A speedometer in New Mexico consists of two components: the speed indicator and counting unit, which counts the traversed path. Both of these have a common ground -; they both work from one drive roller. In addition to these basic units, some types of speedometers have additional devices: daily mileage counter, flashers speed ranges, etc.
Speedometers are mechanically driven (from the flexible shaft), and done so by power. Nearly all car speedometers have speed magnetic assemblies. It is driven by a flexible shaft which has one permanent magnet actuator, which is driven in rotation via a flexible shaft. It is wound with six to seven layers of wire with the opposite winding direction of adjacent layers. Upon rotation of the magnet, its magnetic flux penetrates the coil and it induces eddy currents that create its magnetic field. The coil is rotated in the direction of rotation of the magnet and causes movement of the arrow on the scale of the device.
To improve the accuracy of the speedometer, the magnet and coil is protected from the influence of extraneous magnetic fields. The speedometer torque is transmitted to the shafts and the drive countable node. The speedometer has a pinion assembly, rotating the drive shaft will allow the drum to turn two teeth on the pinion a 1/3 turn. The pinion will rotate again and the drum will hit next two prongs, and so on. The pinion remains stationary until the first side of the drum with two teeth do not complete a full circle.
Thus, each successive drum rotates 1/10 of the turnover, whereas previous drum makes one revolution. A speedometer in New Mexico usually has six drums, hence the count goes up to 100,000 revolutions, and then starts all over again. A speedometer has a flexible drive shaft, which one shaft end is attached to the roller and the other is to an output shaft of the gearbox or transfer gearbox shaft. Flexible shaft speedometers operate normally under the condition that its length does not exceed a certain point.