Sumitomo Special Metals Co., Ltd.

Neomax Co., Ltd.

Hitachi Metals, Ltd.

Tsutomu Harada

Shuichi Okuyama

Takashi Tajiri

Hitoshi Morimoto

Seiichi Kohara

Atsuo Tanaka

Shinji Kidowaki

Shuji Mino

Noboru Nakamoto

Tsuyoshi Hisamura

A press machineincludes a diewith a through holethat defines a cavity, a first press surfaceand a second press surfacefor pressing a magnetic powderloaded in the cavity, and magnetic field generating means for applying an aligning magnetic field to the magnetic powderin the cavity. At least one of the first and second press surfacesandhas a region made of a material having a Vickers hardness that is higher than 200 but equal to or lower than 450. In pressing the powder under the aligning magnetic field, the press machineminimizes the disturbance in the orientation of the powder.

Press machine and method for producing magnet

To avoid various problems caused by remnant magnetization and produce an anisotropic bonded magnet at a reduced cost, a method for producing an anisotropic bonded magnet by feeding a magnetic powder (such as an HDDR powder) into the cavity of a press machine and compacting it is provided. A weak magnetic field is created as a static magnetic field in a space including the cavity by using a magnetic member that is steadily magnetized. The magnetic powder being transported into the cavity is aligned parallel to the direction of the weak magnetic field. Next, the magnetic powder is compressed in the cavity, thereby obtaining a compact.

Production method for permanent magnet and press device

Press and magnet manufacturing method

A method for producing a compact of rare earth alloy powder of the present invention includes: a powder-filling step of filling rare earth allow powder in a cavity formed by inserting a lower punch into a through hall of a die of a powder compacting machine; and a compression step of pressing the rare earth alloy powder while applying a magnetic field, the steps being repeated a plurality of times. When the (n&plus;1)th (n is an integer equal to or more than 1) stage compression step is to be carried out, the top surface of a compact produced in the n-th stage compression step is placed at a position above the bottom surface of a magnetic portion of a die.

Method and apparatus for producing compact of rare earth alloy powder and rare earth magnet

A powder pressing apparatus comprises a die formed with a plurality of cavities. None of the cavities overlap with another in the direction of pushing the compacts. The magnetic field generator includes a pair of yokes sandwiching the die. The yokes and the die have their respective upper surfaces generally in a same plane. A die lubricant is applied to the die but not to a region on which the compacts are to be slid. A rare-earth alloy powder in a feeder box is supplied into each of the cavities. The powder in the cavities is oriented, pressed, and the formed compacts and the yokes are demagnetized. The compacts are pushed and slid off the die on an anti-wear layer, by a flexible pushing member provided in a front portion of the feeder box. The compacts are sintered into rare-earth magnets, which are suitable for a coreless motor.

Powder pressing apparatus and powder pressing method

The present invention provides a powder compacting apparatus including: a die having a through hole forming a cavity; a first punch and a second punch for pressing a rare-earth alloy magnetic powder filled in the cavity; and a magnetic field generator for applying an orientation magnetic field parallel to a pressing direction through the rare-earth alloy magnetic powder in the cavity, wherein at least one of the first and second punches and has a curved pressing surface, and the pressing surface is given a shape such as to suppress the movement of particles of the rare-earth alloy magnetic powder along the pressing surface during the pressing step.

Powder compacting apparatus and method of making rare-earth alloy magnetic powder compact

A powder pressing apparatus comprises an upper punch and a lower punch for compression of a powder in a cavity formed in a through hole of a die. A gap between a side surface of the lower punch and a side surface of the through hole of the die is sealed by a sealing member. A lubricant is supplied with a gas from a nozzle in the side surface of the lower punch to the side surface of the through hole, and the lubricant applied to the side surface of the through hole is spread by an absorbing member. The cavity is filled with the powder while the cavity is under suction by a reduced pressure provided from the nozzle in the side surface of the lower punch. During the suction, a filtering member provides filtration for the lower punch not to draw the powder in.

A rare-earth alloy powder pressing apparatus comprises a die. The die includes a die main body. The die main body includes a through hole for formation of a cavity, and an auxiliary yoke. A rare-earth alloy powder is fed into the cavity. A correcting yoke is disposed near the die, on a side from which a compact is taken out, and an orienting magnetic field is applied. At this time, the correcting yoke is disposed on an upper side of the die if the compact is to be taken out from the upper side of the die whereas the correcting yoke is disposed on a lower side of the die if the compact is to be taken out from the lower side of the die, an inward side surface of the correcting yoke and an inward side surface of the auxiliary yoke are made flush with a plane vertical to a direction in which the orienting magnetic field is applied, and the correcting yoke is urged toward the die. Then, the rare-earth alloy powder is pressed by an upper punch and a lower punch to form a compact. The correcting yoke and the auxiliary yoke may be made integrally with each other.

Growing community of inventors

Settsu, Japan

Tsutomu Harada