Carbon brush conducting structure of autotransformer

Abstract

This invention relates to a conduction structure of carbon brush of an autotransformer, which winds a coil set on a core and sets a carbon brush contacting to the wire and connected with the output end characterizing that when the carbon brush stops, it contacts with one line in the coil set only, which can be realized by using a location device to avoid burning out spare parts or even process switch of large current.

Description

technical field [0001] The present invention relates to a conduction structure of a sliding autotransformer, in particular to a conduction structure in which a carbon brush or an alloy contact only contacts one wire in a coil group when it is in a stopped state. Background technique [0002] At present, the autotransformers produced around the world to adjust the AC voltage all use a copper wire group to wind on an iron core, and different adjustments can be produced by winding different numbers of coils, and each line has a different Voltage value, so connect the corresponding line according to the required voltage value, and then output to the load. [0003] Most of the adjustment devices used today are divided into two types. The first type is the multi-selection switch type (ROTARY SWITCH). Please refer to figure 1 As shown, it connects the specific output voltage from the wires C1, C2, and C3 of the coil group C to the positioning. When the voltage is to be adjusted, t...

AI Technical Summary

Problems solved by technology

When the carbon brush stops or moves, it keeps touching more than one line, which is the so-called cross-line. In this way, the problem of instantaneous power failure of the multiple selection switch can be avoided, but the disadvantage is that the carbon brush stops. When the two wires are in contact, there will be continuous current conduction through the carbon brush, which will cause the temperature of the carbon brush to continue to rise, which will easily cause damage and accelerate surface oxidation.

If it is necessary to use a large-capacity autotransformer, most of them currently use multiple sliding autotransformers in parallel, which is quite inconvenient and consumes materials.

see also Figure 8 As shown, wherein R1 and R2 are the contact impedance of the carbon brush and the line respectively, and R3 is the internal impedance of the carbon brush; according to the formula, the heat is equal to the square of the current multiplied by the impedance (H=I 2 *R), if the impedance of R3 is reduced (such as increasing the copper content in the carbon brush material), the heat generated by the load current should decrease, but the current I1 flowing through the carbon brush increases due to the decrease of R3, so instead It will make the carbon brush body generate more heat, which will cause the temperature of the contact surface to rise and accelerate surface oxidation, which will increase the contact resistance and reduce the efficiency. carbon brushes

[0005] Therefore, how to improve the above-mentioned problems of power failure during the transfer process or carbon brush burnout caused by overheating, etc., and how to improve these shortcomings, and achieve material saving and other functions, are actually issues that are being discussed today.

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