Magnetic encoder and method of manufacturing magnetic encoder

Patent metadata

Field	Value
Publication number	US-12467505-B2
Application number	US-202318214056-A
Country	US
Kind code	B2
Filing date	Jun 26, 2023
Priority date	Aug 8, 2022
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

A cylindrical portion of an annular support member has a small-diameter portion press-fitted to an inner ring of a bearing, and a large-diameter portion formed by enlarging a part of the cylindrical portion, which is closer to an inboard side than the small-diameter portion. An annular magnet member has an inner-diameter side recessed portion formed by depressing, toward an outboard side, a radially inner part of a surface, in an inboard side, of the annular magnet member, and a wraparound portion that wraps around the annular support member toward the outboard side to a stepped portion between the small-diameter portion and the large-diameter portion. An inner peripheral surface of the wraparound portion protrudes radially inward more than an inner peripheral surface of the small-diameter portion. An inner peripheral surface of the inner-diameter side recessed portion has a gate mark of an inner-diameter side disk gate.

First claim

The invention claimed is:

1 . A magnetic encoder for use in a wheel support bearing device of an automobile, the magnetic encoder comprising:
an annular support member made of metal; and
an annular magnet member made of a plastic magnet,
the annular support member includes:
a cylindrical portion that fits on an exterior of an inner ring of a bearing of the wheel support bearing device; and
an outward flange portion extending radially outward from an end portion of the cylindrical portion in an inboard side,

the cylindrical portion has a small-diameter portion press-fitted to the inner ring of the bearing, and a large-diameter portion formed by enlarging a part of the cylindrical portion, the part being closer to the inboard side than the small-diameter portion,
the annular magnet member is attached to a surface of the outward flange portion in the inboard side,
the annular magnet member has an inner-diameter side recessed portion formed by depressing, toward an outboard side, a radially inner part in a surface, in the inboard side, of the annular magnet member, and a wraparound portion that wraps around the annular support member toward the outboard side to a stepped portion between the small-diameter portion and the large-diameter portion of the cylindrical portion,
an inner peripheral surface of the wraparound portion protrudes more radially inward than the inner peripheral surface of the small-diameter portion, the inner peripheral surface of the wraparound portion being press-fitted to the inner ring,
the inner peripheral surface of the inner-diameter side recessed portion has a gate mark of an inner diameter disk gate, and
a portion of the inner peripheral surface of the inner-diameter side recessed portion lies between the wraparound portion of the annular magnet member and the gate mark.

2 . A method of manufacturing a magnetic encoder for use in a wheel support bearing device of an automobile, wherein
the magnetic encoder includes: an annular support member made of metal; and an annular magnet member made of a plastic magnet, the annular support member includes:
a cylindrical portion that fits on an exterior of an inner ring of a bearing of the wheel support bearing device; and
an outward flange portion extending radially outward from an end portion of the cylindrical portion in an inboard side,
the cylindrical portion has a small-diameter portion press-fitted to the inner ring of the bearing, and a large-diameter portion formed by enlarging a part of the cylindrical portion, the part being closer to the inboard side than the small-diameter portion, the annular magnet member is attached to a surface of the outward flange portion in the inboard side, the annular magnet member has an inner-diameter side recessed portion formed by depressing, toward an outboard side, a radially inner part in a surface, in the inboard side, of the annular magnet member, and a wraparound portion that wraps around the annular support member toward the outboard side to a stepped portion between the small-diameter portion and the large-diameter portion of the cylindrical portion, an inner peripheral surface of the wraparound portion protrudes more radially inward than the inner peripheral surface of the small-diameter portion, the inner peripheral surface of the wraparound portion being press-fitted to the inner ring, and a portion of an inner peripheral surface of the inner-diameter side recessed portion lies between the wraparound portion and a gate mark formed in the inner peripheral surface of the inner-diameter side recessed portion, the method comprising:
molding the annular support member by one of (i) pressing and (ii) the pressing and cutting;
applying a thermosetting adhesive to a part of or an entire of a joint surface of the molded annular support member with the annular magnet member;
opening an injection molding die and setting, in the injection molding die, the annular support member to which the thermosetting adhesive is applied, as an insert work; and
closing the injection molding die, and injecting a molten resin in a cavity of the injection molding die from an inner-diameter side disk gate of the injection molding die, to thereby mold the annular magnet member, the inner-diameter side disk gate being arranged at a position corresponding to the gate mark of the annular magnet member.

Assignees

• Nakanishi Metal Works Co

Inventors

• Iizawa Yusuke
• Ito Yoshihiro

Classifications

• G01D2205/26

  Details of encoders or position sensors specially adapted to detect rotation beyond a full turn of 360°, e.g. multi-rotation · CPC title

• F16C2326/02

  Wheel hubs or castors · CPC title

• F16C33/783

  of the mounting region · CPC title

• F16C33/768

  between relatively stationary parts, i.e. static seals · CPC title

• F16C33/7883

  mounted to the inner race and of generally L-shape, the two sealing rings defining a sealing with box-shaped cross-section · CPC title