ELECTROMAGNETIC POLARIZED SWITCH WITH BOUNCE-FREE CONTACT SYSTEM

Abstract

Background. Electromagnetic polarized switches are used in land-based vehicles to commutate the electric circuits in a system. There is a wide variety of industrially available commutating devices, but few of them are applicable for the above purpose due to weight and size limitations. Moreover, the commutating devices are often operated in high-current circuits, requiring retaining of both initial and tailored states of high probability, and reliability under hard impacts and vibrations as well. The above devices are triggered by applying voltage to winding controls. The work provides a design of the electromagnetic polarized switch, suitable for application in both low– and high-current electric circuits of different engineering systems: aircrafts, mobile and stationary facilities. The electromagnetic polarized switch relies upon gained backup contacts of two-sided multipoint contacting to make possible commutation and cutoff of both low and high currents with stable electrical parameters during the long operation life, eliminating closed contacts chatter under significant shock and vibration effects. Materials and methods. Designed electromagnetic switch provides: sizeable moment of retention of the turning armature in the absence of power, that keeps initial and switched state of the contact system; driving moment, produced by the turning armature, suffices for reliable switching of the contact system; augmented angle of the armature turning, that enables use of reliable gained contacts to sustain stable electric parameters for a long operational life, including one under inductive load; power-saving consumption; automatic switch-off power on the control windings when switching state. Results and conclusions. It follows from the resulting calculations of work that during and after the effect of single longwise half-sinusoidal mechanical impact of designed parameters on the switch, the interaction in every couple «spring contact – bridge cutter», retaining the contact transition, is of «gliding» or «glued» type, that excludes contacts chatter. Absence of contacts chatter under impacts and vibration loads is also proved by tests.

Keywords

• electromagnetic polarized switch
• magnetic system
• contact system
• bounce-free contacts
• reliability