speedometer using magnetic mutual inductance, the pointer on the dial and the deflection angle is proportional to vehicle speed. However speedometer odometer distance is indicated by the speedometer of the vehicle speed and the recording cars driving over the composition, both mounted in a common housing, and is driven by the same shaft. With a dial on the scale of the case. It is composed of several odometer count and drum rotating means thereof. For ease of use, while some speedometer and odometer with a total one-way odometer, total odometer to record the total vehicle mileage, one-way one-way cars used to record odometer mileage. One way odometer can be reset to zero at any time. Simply put speedometer shows the speed of cars passing and the record number of modular instrumentation mileage. Commonly used magnetic induction and electronic type.
1. Speedometer alarm
speed alarm device in order to ensure traffic safety and mounted in the speedometer speed audible alarm system. If the vehicle speed reaches or exceeds a certain limit speed, the vehicle speed table in the buzzer circuit switch is turned on, the alarm sounds.
2. Speedometer composition
is a speedometer and odometer speedometer.
1. speedometer
is relatively early mechanical speedometer. Typical mechanical odometer connected to a flexible shaft. The flexible shaft has a wire cable. The other end of the flexible shaft is connected to one gear of the transmission. Gear driven rotary wire rope rotation. Odometer wire rope driven magnet rotating the cover a circle. Bezel coupled to the pointer by the pointer over the zero spring. Speed causes a change in the rotational speed of the magnet magnetic fluxes size. The balance is broken pointer therefore be driven.
This speedometer is simple and practical. It is widely used in small and large cars. but. With the development of electronic technology has begun to use the current car dashboard electronic speedometer, more common form is obtained from the speed sensor on the transmission signal by varying the pulse frequency of a pointer deflection or digital display.
2. odometer
is a digital speedometer instrument, which via a worm gear meshing gears on the counter and speedometer drum shaft, the drum rotates counter. As with the speedometer, odometer now have electronic odometer, it gets a signal from the speed sensor mileage. Electronic odometer mileage accumulated number is stored in the nonvolatile memory, it can be stored in the electroless state status data.
3. Speedometer Category
car speedometer counter roller into the liquid crystal panel and the two kinds of dot pitch, indicated by the speedometer of the vehicle speed and records the car mileage traveled distance meter composition, both mounted in a common housing, and is driven by the same shaft. Most use a counter roller:
1. The counter roller
rollers used in the past counters are purely mechanical instrument, through a flexible shaft, an output shaft connected to the gearbox, the other end connected to the odometer; now more commonly used electronic instruments, it is generally in the transmission output shaft or a wheel speed sensor tops, with the read-out speed to the vehicle speed and course in terms calculated by the control module embedded. Data are from the output of the drive train speed (transmission output shaft or wheel), the known wheel speed, such as revolutions per minute number of laps, then the perimeter of the wheel (i.e. the wheel revolution of distance traveled) count, it came out speed, mileage is the same reason.
4. Precautions
1) a flexible shaft and a transmission or speedometerThe output of splitter should be solid and reliable connection.
2) when the flexible shaft is attached to a certain longitudinal gap, and a sufficiently large radius of curvature.