Oki Electric Industry Co., Ltd.

Masahiro Tatsukami

Hirokazu Andou

Tatsuya Koyama

Tetsuhiro Yamada

Hiroshi Kikuchi

Jiro Tanuma

Mitsuru Kishimoto

Tatsuhiko Shimomura

Katsuya Kamimura

Shugo Suto

Masahiro Shigei

A permanent magnet suitable for use in a wire print head is formed of plural split segments. Each split segment is formed by compressing metal powder in a punching direction in the presence of a magnetic field that is perpendicular to the punching direction. The split segments are combined together into an annular configuration. The permanent magnet so formed is attached to a base, followed by the assembly of a base plate and cores to form a magnet assembly. The base plate and the cores are then surface-finished so as to be flush relative to each other.

Wire print head and process for fabricating it

Wire driving mechanism

A wire dot printing head includes armatures each of which is coupled to a printing wire, a felt guide for reducing the friction between the printing wires and a printing wire guide, a residual sheet disposed over a magnetic core frame, a biasing leaf spring, and a oil leakage preventing member. Such member is disposed over the armatures to intercept oil flowing from the felt guide. An erroneous dot printing operation due to the arms of the leaf spring sticking to the residual sheet is prevented.

Wire dot printer head with oil absorbing member

In a method of fabricating a biasing plate spring for a wire dot print head having an annular part and a plurality of projections extending radially inward from the inner periphery of the annular part, a biasing plate spring intermediate product having two of the projections substantially opposite to each other and connected by an arm, is first formed. The intermediate product is then barrel-polished, and then the arm is removed by cutting. Because of the arm, entry of one intermediate product into the gap between adjacent projections of another intermediate product is prevented, and damage to the intermediate product is thereby avoided.

Method of fabricating a biasing plate spring for a wire-dot print head

A flexible disk drive includes a reset lever which holds an upper head in an upper or open position in an unloaded condition of a magnetic head and, interlocked with a closing motion of a door, moves downward together with the upper head, and a head load arm rotatable in response to downward movement of the reset lever to allow the upper head to make contact with a floppy disk. Connected to the head load arm is toggle device whose biasing direction is inverted by the rotation of the arm to bias the arm toward the disk. A hub adapted to rotate a floppy disk is located to face a collet which is adapted to align the center of the disk with that of the hub. When the door is closed while a floppy disk is not inserted, the collet is brought into engagement with the hub. At this instant, a gap is defined between the upper head and a lower head by a clamp lock to prevent the two heads from making contact with each other. While a floppy disk is inserted, the collet cooperates with the hub to check the disk in response to a closing motion of the door. A sequence lever responsive to a closing motion of the door allows the upper head to contact the disk thereafter. This provides a reliable manual head loading mechanism which insures accurate chucking of a floppy disk.

Manual head loading mechanism for flexible disk drive

Growing community of inventors

Tokyo, Japan

Masahiro Tatsukami