tachometer instrument for measuring the rotational speed of the rotational body, and symmetrically placed together speedometer. Tachometer works according to the principle of magnetism. It receives an ignition pulse signal generated in the coil when the primary current is interrupted. And this signal is converted into speed values can be displayed. The faster the engine speed, the more the number of the pulse ignition coil, shown in the table speed values greater. Most cars are now present in the electronic tachometer, with a pointer and a liquid crystal digital display. Digital integrated circuits in the table. It shipped from the ignition coil after calculating the drive voltage pulse or digital display pointer movement. Another display latter tachometer speed value is sent to the tachometer pulse signal taken from the circuit to explain the generator. However, due to the alternator belt slippage and other factors, so the displayed value is not accurate.
1. Tachometer Category
into the magnetic tachometer tachometer, centrifugal tachometer, electric tachometer, an electronic tachometer, magnetic speed meter, tachometer flash and other types.
1, a magnetic tachometer
using a rotating magnetic field is generated in the metal screw capRotational force, the rotational force of the balancing spring force indicated speed. Magnetic tachometer, is an example of the successful use of a magnetic force, a magnetic force using the principle of the mechanical tachometer; Fair site installation, flexible shaft may be short-range remote installation, easily damaged when the flexible shaft remote installation.
2. centrifugal speed
using a centrifugal force balanced with the tension of the speed indicated. Centrifugal tachometer speed measurement is the most traditional tools, by the centrifugal force principle is a mechanical tachometer; measurement accuracy is generally 1 to 2 grade, generally in situ installation. An excellent centrifugal tachometer intuitive features not only accurate, but also have the advantage of reliable and durable. But the structure is more complex.
3, electric tachometer
by a small alternator, cables, motors, and magnetic table headers. Small AC generator produces an alternating current, an alternating current through the cable delivery, small AC motor drive, the speed consistent with the measured shaft speed compact AC motor. The magnetic head is coaxially connected to the small speed AC motor with speed meter indication magnetic nature is measured shaft speed; and speed electric, remote installation is easy, good vibration resistance.
Electronic tachometer 4.
Electronic tachometer is a more general concept: In modern electronic technology, manufacturing tool design speed measurement. It is generally sensors and displays, and some have a control signal output. Because a variety of aspects of the sensor and the display device, as well as the diversity of the measurement method, it is difficult to classify the same as the first five. Here the electronic tachometer, classified separately from the sensor and the secondary instrument. If you use up points from the installation, as well as local mount, desktop, counter-mounted and portable and handheld.
5, magnetic tachometer
magnetic sensors plus ammeter, is easy to install in different places.
6, flash tachometer
using the principles of persistence of vision. Flash tachometer, in addition to detecting rotational speed (reciprocation speed), the cycle can also be observed motion of the object still on the understanding of the mechanical equipment operating state, it is a necessary tool for observation.
2. Tachometer characteristics
1) can be measured in the range of 50mm-1.5m from the object with a laser beam.
2) using the supplied adapter contact measurement.
3) may display a large number, the unit of LCD type display and can emit light in the dark clear confirmation of two kinds of series type LED.
4) can store maximum, minimum, final measurement 10 kinds of data.
5) high quality durable aluminum housing.