JPH071730B2 - Composite magnet and manufacturing method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a magnet in which a permanent magnet manufactured by powder metallurgical means and another metal member are combined with each other by a boundary surface parallel to the central axis, particularly, a magnet. The present invention relates to a composite magnet for a magnetic sensor and a manufacturing method thereof.

[Conventional technology]

As a sensor for detecting the approach or passage of a magnetic material, a combination of a composite magnet and a magnetic semiconductor element is known. Examples of the composite magnet include, for example, a soft magnetic material having a high magnetic permeability and a permanent magnetic material on both sides. The one that is pasted is used. When a strong residual magnetism is required as the permanent magnet, for example, a Mn-Al-C alloy molded by powder metallurgical means is used.

[Problems to be Solved by the Invention] In order to manufacture a composite magnet by laminating as described above,
It was necessary to perform a highly accurate partitioning process on each bonding surface, and the production was extremely inefficient. In addition to this, it is difficult to weld, braze, and machine permanent magnet materials,
When attaching a yoke, a supporting member, or the like, it is unavoidable to use an adhesive, resulting in problems in vibration resistance and impact resistance.

INDUSTRIAL APPLICABILITY The present invention makes it possible to increase the manufacturing efficiency by eliminating the finishing process for each material, and to attach the yoke and the supporting member by means of high vibration resistance and impact resistance such as welding, brazing and machining. It is intended to obtain a composite magnet.

[Means for Solving the Problems]

The composite magnet according to the present invention has a state in which a plurality of materials are in close contact with the inner wall surface of the outer shell and in a boundary surface of each other in a cylindrical outer shell made of a metal having sufficient strength and malleability. Is held in. Here, the boundary surface is substantially parallel to the central axis of the outer shell, the material is made of a permanent magnet metal and a non-permanent magnet metal, and all of these metal materials are solid.

Such a composite magnet is manufactured as follows. First, a partition made of a solid non-permanent magnet material is inserted into a cylindrical capsule made of metal having sufficient strength and malleability to partition the inside of the capsule. This partition has a surface parallel to the central axis of the capsule. Then, the partitioned space in the capsule is filled with a solid metal or powder material, and at least one space is filled with a permanent magnet powder material. Next, the capsule filled with the material is sealed, and hot or warm extrusion is performed using this as a billet to obtain an extruded material having a reduced diameter. Finally, this extruded material is cut into a predetermined length to obtain a product composite magnet.

[Action]

In the above-mentioned manufacturing process, the metal powder material filled in the capsule is changed into a solid material during the extrusion process, and highly adheres to the outer shell transferred from the capsule and the surface of the partition. Also,
The partition inserted into the capsule is stretched together with the capsule during the extrusion process, but the surface thereof continues to be substantially parallel to the central axis of the outer shell transferred from the capsule.

Therefore, in the composite magnet obtained by cutting this, the solid metal material transferred from the powder material and the metal material transferred from the partition etc. are almost parallel to the central axis of the outer shell in the cylindrical outer shell. These materials have a high degree of close contact with each other, and include permanent magnet materials among these materials.

Therefore, finishing processing for each material is unnecessary, each material does not separate even though no adhesive is used, and a product with a predetermined size can be obtained only by cutting the extruded material,
Its manufacturing efficiency is extremely high. Further, since the yoke, the supporting member and the like can be attached to the outer shell by welding, brazing, machining or the like, a final product having high vibration resistance and impact resistance can be obtained.

Example 1 Example 1 As shown in FIG. 1 (a), a partition 2 is placed inside a cylindrical capsule 1.
Then, the metal powders 3 are filled in the partitioned space, the lid 4 is welded, and the inside is evacuated to manufacture the billet 5. The materials and dimensions of each part are as follows. 6 is a central axis of the capsule 1.

Capsule 1 Material: SUS304 Dimension: Outer diameter 33mm, Inner diameter 29mm, Bottom thickness 5mm, Recess depth 40mm Partition 2 Material: 45 Permalloy Dimension: Thickness 1.5mm Metal powder 3 Material: MnAlC series permanent magnet alloy Lid 4 Material: SUS304 Dimensions: diameter 33 mm, thickness 5 mm The billet 5 was heated to 700 ° C. and hot extruded to obtain a hot extruded material 7 with a diameter of 16.3 mm and a length of 145 mm shown in FIG. 1 (b). . The length of the central cladding 8 is 10
The length of both end portions 9, 9 originating from the bottom 1a of the capsule and the lid 4 was about 18 mm.

By cutting the above-mentioned extruded material 7 into a length of 10.0 mm, a composite magnet 10 having a longitudinal section in FIG. 1 (c) and a transverse section in FIG. 1 (d) can be obtained. This composite magnet 10 is
On both sides of partition 11 made of 1.2 mm 45 permalloy, MnAlC
The permanent magnets 12 and 13 of the system alloy are in close contact with each other, and the cylindrical outer shell 14 of SUS304 material which is a non-magnetic material is in close contact with them, and the boundary surface between the partition 11 and the permanent magnets 12 and 13 is Central axis 15
Parallel to.

FIG. 2 shows a magnetic sensor using the composite magnet 10.
The permanent magnets 12 and 13 are magnetized in opposite directions as shown in the figure, and a yoke 16 made of 45 permalloy is provided on one end surface of the composite magnet 10 and welded to the outer shell 14. 1
Reference numerals 7 and 17 denote mounting screw holes formed in the yoke 16. Composite magnet 1
When the magnetic semiconductor element 18 is arranged close to the other end surface of 0, a detection signal appears in the element 18 when the object 21 moves in the directions of arrows 19 and 20.

In the embodiment shown in FIG. 3, instead of welding the yoke 16 to the outer shell 14, the yoke 16 is screwed to the screw 22 processed on the outer shell 14.

Example 2 Instead of the capsule 1 and the lid 4 made of the SUS304 material in Example 1, the capsule 1 and the lid 4 made of brass were used, and only the thickness of the bottom 1a was set to 15 mm. All other matters are the same as in Example 1. The reason for thickening the bottom 1a is 700 ° C.
The brass becomes extremely soft during hot extrusion at
The capsule 1 has a tendency to be squeezed out from the die before the side wall portion 1b of the permanent magnet materials 3 and 3, but if the die is passed through from the thick bottom 1a side, the permanent magnet materials 3 and 3 are formed.
Is smoothly introduced into the die.

In the product according to this embodiment, the brass outer shell 14 is welded to the inner partition 11 and the outer peripheral surfaces of the permanent magnets 12 and 13 to be integrated with extremely high strength.

In addition, the outer shell 41, the soft magnetic materials 42, 42 ... And the permanent magnet materials 43, 43 ... As shown in FIG.
.. can be applied to the production of composite magnets of various shapes.

〔The invention's effect〕

As is clear from the above examples, according to the present invention, it is possible to extremely efficiently manufacture a composite magnet including a metal permanent magnet as a part of the powder raw material plastic working, and the composite magnet is welded or brazed. It is easy to contact and machine, and has excellent vibration resistance and impact resistance.

[Brief description of drawings]

FIG. 1 is a vertical sectional view for explaining a manufacturing process in an embodiment of the present invention, FIGS. 2 and 3 are sectional views showing a processing example of a product according to the same embodiment, and FIG. It is a cross-sectional view of various examples of products. 1 ... Capsule, 2 ... Partition, 3 ... Metal powder, 4 ...
... Lid, 6 ... Central axis, 7 ... Hot extruded material, 10 ... Composite magnet, 11 ... Partition, 12 and 13 ... Permanent magnet, 14 ... Outer shell, 15 ... Central axis, 41 ... … Outer shell, 42… Soft magnetic material,
43 …… Permanent magnet.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ichiro Takasu 3007 Nakajima, Shikama-ku, Himeji, Hyogo Prefecture Sanyo Special Steel Co., Ltd. Special Steel Co., Ltd.

Claims (2)

[Claims] 1. A plurality of kinds of metals, each of which is a metal permanent magnet material, in which at least one of which is a powder raw material is enriched by plastic working in a cylindrical outer shell made of a metal having sufficient strength and malleability. A composite magnet, wherein materials are present and these materials are in close contact with each other at a boundary surface substantially parallel to the central axis of the cylinder. 2. A partition made of solid metal having a surface parallel to the central axis of the capsule is inserted into a cylindrical capsule made of metal having sufficient strength and malleability, and at least one of the remaining spaces. Was filled with a powder material of a permanent magnet metal, and a powder of a suitable metal or a solid metal material was housed in the remaining space, and the capsule was sealed and subjected to hot or warm extrusion processing. A method for producing a composite permanent magnet, which comprises cutting an extruded material into a predetermined length.