Plastic speed target wheel and method of manufacture

摘要

A speed target wheel includes an annular body portion and a plurality of gear teeth. The annular body portion consists of a plastic material and the plurality of gear teeth project from the annular body portion. Each of the plurality of gear teeth includes a base portion adjacent the annular body portion and a tip portion, where the base portion is integrally formed with the annular body portion and substantially comprises the plastic material, and where the tip portion includes a ferrous region integrally encompassed by the plastic material.

主权项

1. A speed target wheel comprising:
an annular body portion consisting of a plastic material; and a plurality of gear teeth projecting from the annular body portion and each of plurality of gear teeth including a base portion adjacent the annular body portion and a tip portion adjacent the base portion, wherein the base portion is integrally formed with the annular body portion and comprises the plastic material, and wherein each tip portion includes a ferrous region consisting of a single ferrous member integrally encompassed by the plastic material, wherein the ferrous region is included in each of the gear teeth in an amount and is disposed at a location that is effective to generate a signal in a Hall effect sensor disposed for reading the movement of the ferrous region such that the signal generated by any one of the gear teeth is substantially identical to the signal generated by any other of the gear teeth, and wherein the plurality of gear teeth have a predefined width, and wherein each ferrous member has a length that is approximately the same as the predefined width.