SU448455A1 - Contactless key - Google Patents

Description

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The proposed key is intended for manual entry of information, for example, into communication channels, computing, measuring and printing devices, into various automation systems. It can be used in computing, telegraphy, typewriting, and instrument making, both as a separate module and as a keyboard assembled from them.

Keys of a similar purpose are known, based on capacitive, photoelectric, and magnetically sensitive operating principles.

There are also keys in which the magnetically sensitive element (Hall sensor, magnetoresistor) changes its electrical parameters depending on the induction of the magnetic field acting on it.

In known keys, the value of the magnetic induction acting on the magnetically sensitive element depends on the position of the permanent magnet, which when pressed on the key of the key can move relative to the magnetically sensitive element, and after relieving the pressing force, return to the initial (starting) position.

In order to simplify the design, increase reliability and durability, reduce overall dimensions, a key is offered, into the case of which a magnetic system is placed, consisting of a stationary ring-shaped permanent magnet with a lip at the end and a magnetically sensitive element on

its surface and core with a core connected to the key head guide.

The drawing shows the proposed key, a longitudinal section.

In the diamagnetic case 1, the key is reinforced, for example, by an aid of columns 2 an annular permanent magnet 3. At its end there is a soft magnet magnet 4, and in the hole of the magnet there is a core 5 connected by its movable crust 6 with a guide key 7. The core with The core along with the keyhead can be moved along the key axis by an amount equal to the working stroke. The magnetically sensitive element 8 is installed and the hole of the magnet 3 on the surface of the frame 4. The housing 1 has a cavity 9 for accommodating the electronic circuit elements.

In the drawing, the proposed keypad is shown in the initial (starting) position, in which the core 5 is retracted into the hole of the magnet and together with the bark 6 and the key head 7 is in the extreme position.

When you press the keyboard head, the core moves along the key axis, increasing the air gap between the magnetically sensitive element and the end of the core. This reduces the magnetic induction acting on the magnetically sensitive element. After removing the force of pressing, under the influence of magnetic force lines that draw the core into the hole and pull it to the end of the magnet, the movable part of the key moves up and takes the initial (starter) position. In this case, sticking of the core core to the end of the magnet provides the key with vibration resistance and creates the so-called effect of the feeling of the initial state.

The subject of the invention is a contactless key comprising a housing in which an axially magnetised annular constant magnet, a rim mounted in the form of a flange, measles with a core, a magnetically sensitive element, such as a galvanomagnetic sensor mounted in an air gap, is installed; the head, characterized in that, in order to increase the reliability of its operation and simplify the construction, the yoke is fixed on one end of the ring-shaped permanent magnet, and on the other there is measles, ny with key golozkoy situated coaxially with the core side yoke.

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