2006-09-04 03:35:03 · 3 answers · asked by JurisprudentialGod 1 in Cars & Transportation ➔ Maintenance & Repairs
... "The cable is connected to a gear at the transmission. This gear is designed for a specific model, tire size, and rear axle ratio. The speed indication of an analog speedometer works on the magnetic principle. It includes a revolving permanent magnet driven by the cable connected to the transmission. The magnet sets up a rotating magnetic field which exerts a pull on the speed cup, making it revolve in the same direction. The movement of the speed cup is slowed and held steady by a hairspring attached to the spindle of the speed cup. The speed cup comes to rest where the magnetic drag is just balanced by the retarding force created by the hairspring. The hairspring also pulls the pointer of the instrument back to zero when the magnet stops rotating. As the speed of the magnet increases, due to movement of the car, the magnet drag on the speed cup increases and pulls the speed cup further around. In that way, a faster speed is indicated by the pointer on the face of the dial. The magnetic field is constant, and the amount of movement of the speed cup is always proportional to the speed at which the magnet is being rotated. " ...
2006-09-04 07:04:44 · answer #1 · answered by Blazs (Skoda 120GL) 3 · 1⤊ 0⤋
it has a long thin cable that is inside a flexible tube goes from the speedometer head to a generator on the transmission ,the generator has gears in it that reduces the speed of the cable that spins and turns the speedometer head
2006-09-04 10:46:51 · answer #2 · answered by Jerpatti 1 · 0⤊ 0⤋
There is a worm gear on the final drive of the transmission, it turns a cable. The cable attaches into the work gear in the back of the speedometer. It turns a gear that has a damper spring or damper clutch attached to it. The needle is attached to the clutch or spring. Good luck.
2006-09-04 10:42:07 · answer #3 · answered by jeff s 5 · 2⤊ 0⤋