Reed switches in Gear speed and direction sensing

Mechanical machinery always have a set of manual controls that not only direct the machinery between a forward and reverse operation but also change the speed of the operation. This sort of manual positions systems need to be translated to a digital form for microprocessor based decision making. Such machinery always have multiple gear mechanism that can be sensed using reed switch based products such as gear speed sensors to feed information to the central control based on the machine operators control decisions.
Miniature ferrous part detection sensors are positioned near the gears to sense the speed of rotation. Reed Switch based sensors have very high sensing speeds and can sense up to 30,000 RPM. Special ferrous part sensors which can sense gear direction are built with two reed switches and a biased magnet and combining this system with a D-Flip-flop for quadrature sensing. One of the reed switches is connected to the D input, and the other clocks the input. This way, one direction is differentiated from the other by monitoring the output Q of the D-FF.
Application Classification
Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or Relay, Temperature Sensing or Magnet Biasing types. This application is classified as follows and the link gives more information on best practices to help select the most suitable AT band and matching magnet.
Position sensing Type
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Position Sensing type application When an application requires the end position of a movement sensed, or the sensing of a part when it
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Nov 7, 2020 |
Recommended Products
The Reed Switches and Sensors used in such applications need to be robust, durable and efficient in meeting a high life expectancy. Our engineers work hard in life testing our products under various conditions, and our intention is to ensure end product durability and life. Although we wouldn’t want to restrict any of our products for use in only certain applications, the recommended products for use in this application are listed below.
RM-1318 Reduced Miniature Reed Switch
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The RM-1318 Reduced Miniature reed switches are designed for applications where a size restriction is present, but a higher Contact
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Nov 8, 2022 |
MO-1422 Miniature Off-Centre Contact Reed Switch
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This MO-1422 Miniature Off-Centre Contact Form A type Reed Switch is designed for highly sensitive magnet applications when the
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Dec 2, 2020 |
MC-1425 Miniature Close-differential Reed Switch
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This Form A type MC-1425 Close Differential Reed Switch is built with specially pressed blades with slightly higher rigidity for close
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Nov 8, 2022 |