Approach sensor for improving positioning accuracy for periphery components of checking coils

Abstract

Provided is a proximity sensor having low positional variations between a core and a core spool resulting in low detection characteristic variations between products and having excellent assembly workability. In a winding body part of the coil spool for winding a lead wire of a detection coil, protrusions protruded from three or more positions distributed in the area wider than a half of the circumference of the winding body part toward the center are arranged to be brought into resilient contact with the shaft part of the core for positioning the coil spool and the core shaft part concentrically.

Description

technical field [0001] The invention relates to a high-frequency oscillation proximity sensor, especially having specific features in the positioning structure of the coil frame and the iron core; the invention also relates to an assembly method of the coil frame and the iron core of the proximity sensor. Background technique [0002] In the high-frequency oscillation type proximity switch, it is necessary to keep the product-to-product variation of the detection characteristics represented by the detection distance below a specified value. In order to reduce the deviation of detection characteristics, in most cases, during the assembly process of the product, the circuit is adjusted with variable resistors, etc. If the deviation of the position of the components is small, the adjustment range of the circuit can be reduced, or the adjustment of the circuit can be unnecessary. [0003] However, the iron core is made by molding ferrite powder and then sintering, and it shrink...

AI Technical Summary

Problems solved by technology

However, in this structure, it cannot be ensured that the bobbin is concentric with the iron core and the iron core is concentric with the coil box

[0007] In any of the above-mentioned existing technologies, it is impossible to ensure the concentricity and axial positioning of the iron core, coil frame and coil box at the same time with very high precision.

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