Sony Precision Technology Inc.

Mori Seiki Co., Ltd.

Gunichi Nakamura

Mitsuru Ohno

Masaaki Kusumi

Nobuhiro Nakagawa

Disclosed herein is a position sensor including, a magnetic recording medium including two incremental layers and an absolute layer, the absolute layer provided between the incremental layers, each of the layers having magnetic information recorded therein, and a magnetic detection section including three magnetoresistance effect devices opposite to the layers of the magnetic recording medium, being moved relative to the magnetic recording medium in the extending direction of the layers, and being operative to detect the magnetic information in the layers by the magnetoresistance effect devices.

Position sensor and bias magnetic field generating device

In a scale device including a case member () having a guide opening () formed therein, seal lip members (A,B), a carrier unit () having seal lip pressing means () formed thereon, and a coupling member () which slides inside and relative to the guide opening (), the seal lip members (A,B) are pressed at end portions () thereof by the seal lip pressing means () in the vicinity of opposite end portions () of the coupling member () to prevent the seal lip members (A,B) from being spread. Thus, any gaps can be prevented from taking place between the seal lip members (A,B) and coupling member () in the vicinity of the opposite end portions () of the latter. Therefore, dust or the like can be prevented from entering the case member ().

Scale device including means for preventing the occurence of small gaps between opposing walls of a guide opening

In a scale device including a scale unit () and detector (), the scale unit () includes a scale member () formed from a long material and having at least a pair of fixing holes () formed therein across a position signal carrying area () defined thereon and which carries position signals, and a case member () housing the scale member () therein and having formed therein a pair of fixing holes () through which there is inserted a fastening member () to be screwed into a mounting hole () formed in a stationary part () of a machine to which the scale device is to be installed. The detector () is fixed to a moving part () of the machine, which moves relative to the stationary part (), and includes a sensor () which moves oppositely to the position signal carrying area () on the scale member (). The scale unit () is fixed to the stationary part () with the scale member () and case member () being fastened together by the fastening member (). Thus, the scale member () different in linear expansion coefficient from the stationary part () can be installed to the latter with a high precision, and the scale device can make a measurement with a high accuracy, independently of environmental conditions.

Growing community of inventors

Kanagawa, Japan

Gunichi Nakamura