Magnetic rotary encoder！

Magnetic rotary encoder
Magnetic encoder essentially robust, in shock, vibration and high temperature reliable operation. Magnetic debris into the magnetic rotary encoder can degrade performance, but not other contaminants. Therefore, regular rotary magnetic encoder instead of the optical encoder. In one rotation of the rotor code wheel or strip passive or variable reluctance sensor senses the magnetic strip by either a Hall effect or magnetoresistive. Motor speed and position accuracy which is more suitable for applications both dictation.
Magnetic rotary encoder can be used in high-volume applications in small, inexpensive equipment, in the form of a vehicle: anti-lock brake systems, units or demanding motion tasks complex control systems such as industrial automation and medical equipment. Available change is gradual and absolute type; non-contact and bearing versions; and the unit cells and the encoder rotation mechanism which is separate valid child.
In short, MOST Hall-effect magnetic encoder installed in the track wheel motor shaft and the wheel is magnetized with the north and south poles around its periphery. Usually it is from the injection molding with ferrite pole embedded array made.
For example, a 15 mm encoder consists of a 7.6 mm diameter, using a static magnetic pole jig 32 (16 16 North and South). Jig size limit is usually the number of poles can be embedded. For 32-pole engine acerca pole pitch of 0.75 mm, the minimum practical size with jig can handle.
Using target disk plus a magnet circuit commutation signal that is picked up from round three digital Hall-effect sensor (120 ° electrical away) is usually set to consider. Hall-effect sensor switch, when open through north and south poles.
Shown here is the press roller with a magnetic share many CARACTERÍSTICAS no bearing and an encoder according to this technique, based on reluctance, tachometer. The main difference: the encoder, wherein the track position, tachometer only measure speed.
Shown here is the press roller with a magnetic share many CARACTERÍSTICAS no bearing and an encoder according to this technique, based on reluctance, tachometer. The main difference: the encoder, wherein the track position, tachometer only measure speed.
Hall effect encoder output switch usually consists of hysteresis characteristics - When you reach a sufficient magnetic flux density from the rotary encoder wheel to overcome critical threshold level. Similarly, when the detected field reaches below the threshold level is low flux density, it switches back to the previous state. Therefore, including 32-pin encoder wheel 16 pulses per revolution Hall sensors generate container.
It is not only the size of the encoder generally this type of operation lever. Some of miniature single-chip design of the magnet system integration field sensing Hall elements and digital signal processing for simultaneous absolute, incremental, and pulse width modulated digital output. Small diameter magnet polarization rotation ASIC above; Hall effect sensor which comprises an array of magnetic flux change detecting and as a magnet rotating above the voltage generated.
Magnetic rotary encoder allows a unique setting. Shown here is one in which the connection magnetic rotor and belts, couplings, and traditional design is flexible strip by a flexible tape buckle eliminates design. This design is suitable for the motor shaft.
Magnetic rotary encoder allows a unique setting. Shown here is one in which the connection magnetic rotor and belts, couplings, and traditional design is flexible strip by a flexible tape buckle eliminates design. This design is suitable for the motor shaft.
Today, however, require higher resolution and high-end from miniature encoders - through increasing use of magnetoresistive material encoder according to the presence acerca 1.6% decrease in volume resistivity saturation field meet. Magnetoresistive sensor from a Hall effect sensor differs in two important ways. First, saturating field is in the range of 0.003 to 0.005 T, the amplitude of the field than a typical digital Hall sensor switch an order of magnitude. This makes it more sensitive measuring equipment magnetoresistors. Second, the change in resistance is independent of the polarity of the magnetic field, the magnetic pole 32 so that each wheel revolution pulse generator 32, twice the resolution of the sensor of the prior art.
Magnetoresistive sensor assembly includes a thin Ni - Fe permalloy strip array.
It is much greater than the thickness of the strip width. Sensor is positioned above the tracks of the encoder wheel with strips parallel to the wheel axis.
While we focus on the Hall effect and magnetoresistance type, inductive encoders is the third most common type of rotary magnetic encoders. In one or more of them through the tracking coils reactionary resistance current flow (in the vicinity of the project) to operate. Soft iron or ferrite high temperature sensitivity may cause problems. The external magnetic field can present their permeability push material far below the saturation point. One option is coreless inductive rotary encoders as a: vortex generators Compare up to 120,000 RPM provides 64 pulses.
This magnetic wheel mounted directly on the end of the Estado Salakazi drag motorcycle shaft, and the encoder main body of the clutch housing. Encoders withstand extreme temperatures and acceleration beyond 300 km / h 1500 horsepower bike race in less than seven seconds; it provides feedback wire wheel speed, steering, and transmission applications. Source: Renishaw.
This magnetic wheel mounted directly on the end of the Estado Salakazi drag motorcycle shaft, and the encoder main body of the clutch housing. Encoders withstand extreme temperatures and acceleration beyond 300 km / h 1500 horsepower bike race in less than seven seconds; it provides feedback wire wheel speed, steering, and transmission applications. Source: Renishaw.
Magnetoresistive sensor from a channel formed by the staggered half pole pitch two strips. They are connected to the double differential output voltage of the sensor. As the encoder wheel rotates through one pole (two sensing plate), the output voltage of a complete cycle, from generating a 5-volt DC power supply 40 mV peak - peak signal.

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