Hall speed sensor for rail transit and manufacturing method thereof

Abstract

Provided is a Hall speed sensor for rail transit, including an integrated device base, a low-pressure injection molding module, a tail pipe, an anti-rotation ring and a pressing cap; a limiting mechanism is arranged between the inner cavity of the integrated device base and the anti-rotation ring, and a phase positioning mechanism is arranged between the inner cavity of the integrated device baseand the low-pressure injection molding module; a printed board mounting groove is formed in the inner cavity surface of the tail pipe; the anti-rotation ring is arranged on the tail pipe in a sleevedmode and is arranged in the inner cavity of the integrated device base, and the anti-rotation ring is limited by a limiting mechanism; and the outer circle surface of the pressing cap is in threaded connection with the tail part of an integrated shell, an anti-rotation ring extrusion surface is arranged at the front end of the pressing cap, so that the low-pressure injection molding module and theintegrated device base are in close contact and fixed by extruding the anti-rotation ring extrusion surface to compress the anti-rotation ring when the pressing cap rotates; the low-pressure injection molding module comprises an internal core part and a supporting part, the internal core part forms a supporting part outside through plastic low-pressure injection molding, two parallel waist-shapedplane notches are formed in the outer cylindrical surface of the low-pressure injection molding module, the surfaces of the waist-shaped plane notches are parallel to the plane of the printed board of the internal chip. Correspondingly, the invention provides a manufacturing method.

Description

technical field [0001] The invention relates to a Hall speed sensor for rail transit. Background technique [0002] The 2-channel Hall principle speed sensor is composed of permanent magnets, Hall elements, amplification and shaping circuits, housings, cables, connectors and other components. The magnetic steel, Hall element and amplification and shaping circuit are packaged inside the shell, and the shell has a mounting and positioning structure; it is electrically connected to the system through cables and connectors, and the power supply to the sensor and the output speed signal are installed on the rotating shaft of the measured speed A speed measuring chainring, the sensing surface of the speed sensor is close to the chainring. The rotation of the gear plate makes the reluctance of the magnetic circuit change periodically with the change of the air gap. When the top of the tooth is aligned with the Hall element, the magnetic force lines pass through the Hall element co...

AI Technical Summary

Problems solved by technology

[0003] The conventional Hall speed sensor housings currently used in the rail transit industry mostly use split metal housing components. The inner core component and the housing component are fixed by colloidal potting and filling. The product has poor manufacturability and long production cycle. The cost is high, and due to the internal stress relief structure without glue, it is prone to failures such as solder joint breakage when used in a long-term environment with large temperature changes, and the product reliability is poor

Non-modular design, it is impossible to shorten the production cycle by preparing materials in advance and pre-producing core modules, and the customer response cycle is long

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