Ceramic reed switch

Abstract

A ceramic reed switch belongs to the technical field of reed switches. The ceramic reed switch comprises a ceramic tube, and a first end cover and a second end cover which are arranged at the two ends of the ceramic tube, the interior of the ceramic tube is a sealed chamber, a first pin is arranged on the outer side of the first end cover, a first magnetic reed is arranged on the inner side of the first end cover, the first magnetic reed forms a cantilever beam structure on the first end cover, a second pin is arranged on the outer side of the second end cover, a second magnetic reed is arranged on the inner side, the second magnetic reed forms a cantilever beam structure on the second end cover, the free ends of the first magnetic reed and the second magnetic reed are overlapped in the ceramic tube and form an air gap, and the overlapped ends of the first magnetic reed and the second magnetic reed are provided with contacts. The ceramic reed switch inherits the advantage that a traditional reed switch is simple and reliable in structure, and inherent defects of the traditional reed switch technology are avoided.

Description

technical field [0001] The invention belongs to the technical field of reed switches, and in particular relates to a ceramic reed switch. Background technique [0002] The magnetic reed switch is also called a reed switch. It is an electrical switch operated by an applied magnetic field. The basic type is to seal two magnetic reeds in a glass tube. Although the two pieces overlap, there is a small air gap between them. When an external magnetic field is applied, the two magnetic reeds will be attracted and contacted, so that the current flows through the magnetic reeds to achieve contact connection. Once the magnetic field is away from the switch or disappears, the magnetic reeds will return to their original state under the action of their own elastic reaction force. The overlapped part of the two magnetic reeds re-forms an air gap to realize contact breaking and disconnect the circuit. [0003] Therefore, the traditional reed switch belongs to a structure in which the mag...

AI Technical Summary

Problems solved by technology

The large-load reed switch and reed relay are ideal switching elements for short-wave communication, electric trains and explosion-proof electrical equipment electrical control systems. When traditional reed switches are connected to large load currents or high-frequency currents, due to soft magnetic The resistivity of the reed is high, and the current will make the reed more likely to heat up, resulting in high temperature demagnetization of the magnetic circuit, resulting in unreliable contact of the pull-in contact

Since the pins of the traditional glass reed switch are also iron-nickel alloys with a soft magnetic expansion coefficient close to the glass, they have the characteristics of large resistivity and large bending stress of the pins, and the pins and the soft magnetic reeds together constitute a dry reed The magnetic circuit of the tube is applicable. Cutting off or bending the pins will directly cause the magnetic circuit of the reed tube to change, which will cause the key technical index AT value of the reed tube to change accordingly, resulting in a change in the reed switch. The driving parameters of the tube vary with the installation method used, so that the precisely controlled AT value in the design and manufacturing process can only be a reference value in actual use, and the consistency of the circuit cannot be guaranteed

In addition, due to the large bending stress of the iron-nickel alloy, especially the large-load reed switch with a thicker diameter often breaks or leaks the glass tube at the sealing part of the reed switch during actual use, which seriously damages the reliability of the reed switch. sex

These defects are the inherent defects of current glass reed switch products, which are difficult to avoid

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