JPH0645136A - Iron core for electromagnet - Google Patents

Abstract

PURPOSE:To coat a bent iron core evenly with polyparaxylylene resin of low abrasion coefficient. CONSTITUTION:Bent part of an iron core 31 can be evenly and stably coated with polyparaxylylene resin by processing the iron core with silane before evaporating polyparaxylylene resin as the coating resin of low abrasion coefficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron core for an electromagnet.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for miniaturization and thinning of relays. Along with this, rationalization of parts has been studied and the number of parts has been reduced. That is, when the coil wire is wound around the iron core, a coil frame is not used, and the coil wire is directly wound by applying an insulating protective coating to the iron core. When using a coil bobbin, the number of parts increases, there is a limit to cost reduction, there is a limit to downsizing, and it is necessary to separately protect the collision surface of the iron core and the armature. Is.

In the above-mentioned method of reducing the number of parts, the insulating protective coating is applied to the iron core in this case, when a part of the iron core is wound at the time of winding.
This is for example to prevent the coil wire from being damaged at the corners and the like so that the coil wire is not broken during use. In addition, when this type of relay is used for a long period of time, when the armature collides with the iron core, abrasion powder generated from the iron core adheres to various parts such as the relay, resulting in insulation deterioration and poor contact. It is also to prevent that.

[0004]

As a method of forming a coating on an iron core, there is, for example, a method of forming a coating on the surface of the iron core by spraying. However, according to this, it is difficult to control the film thickness, in particular, it is difficult to avoid thinning at the corners, and it is difficult to sufficiently secure the electromagnetic characteristics and eventually the relay characteristics.

In view of the above circumstances, the present invention provides an iron core for an electromagnet having a stable characteristic in which a coil wire can be safely wound around an iron core and which does not cause coil breakage, and the generation of magnetic pole consumable powder. It is an object to provide an iron core for an electromagnet that can be effectively prevented.

[0006]

In order to achieve the above object, the present invention provides an iron core having both sides bent and a coil winding wound around an intermediate outer periphery to form an electromagnet. After the silane treatment, the vapor deposition film of polyparaxylylene is formed.

[0007]

According to the present invention, in an iron core having both sides bent and a coil winding wound around an intermediate outer periphery to form an electromagnet, the surface of the iron core is subjected to silane treatment, and then a vapor deposition film of polyparaxylylene is formed. By forming the above, it is possible to form a uniform and stable coating film of polyparaxylylene on the bent portion of the iron core having the bent portion.

[0008]

Embodiments will be described in detail below with reference to the drawings showing the embodiments.

FIG. 1 (a) shows an embodiment of an iron core according to the present invention, and FIG. 1 (b) shows an enlarged cross section orthogonal to its axis. The entire surface of the iron core 31 is covered with the vapor deposition coating 31a. In this embodiment, the vapor deposition coating 3
1a is made of a vacuum deposition film of polyparaxylylene. Parylene resin (Union Carbide Co.) is known as a commercially available product of polyparaxylylene. The polyparaxylylene has the characteristics of high electric insulation and high heat resistance. The film thickness of the vapor deposition film is 3 to 5
It is generally about micron, but not limited to this.

There is no particular limitation on how to form such a vapor-deposited coating, but for example, there are the following methods.

As shown in FIG. 2, a diparaxylylene (dimer) is placed in an evaporative decomposition furnace 60 made of quartz glass or the like.
Put materials such as, temperature 175 ° C or less, pressure 1T
Evaporation is performed under the conditions of about ORR or less. In the figure, reference numeral 62 denotes a lid of an evaporative decomposition furnace, and a sealing material such as grease is interposed between the lid 62 and the evaporative decomposition furnace 60.

Evaporated diparaxylylene has a temperature of 6
It is thermally decomposed under the conditions of about 80 ° C. or less and the pressure of about 0.5 TORR or less to form para-xylylene (monomer). The para-xylylene enters the barrel 80 provided in the vacuum chamber 70 through the gas passage 61. A barrel 80 is supported and rotated by a shaft 81 in the vacuum chamber 70.
The inside of the vacuum chamber 70 communicates with a vacuum pump via a vacuum suction port 72. In the figure, 71 is a seal member, and a seal material such as grease is interposed between the seal member 71 and the gas passage 61 constituent member and the shaft 81. The gas passage 61 faces the inside of the barrel 80.

A work piece 90 serving as the iron core 31 is contained in the barrel 80. Rotate the barrel 80, temperature 2
When vapor deposition is performed under conditions of about 5 ° C. and a pressure of about 0.1 TORR, the paraxylylene gas forms a uniform coating film 31 a of polyparaxylylene on the entire surface of the work 90. The para-xylylene repetition degree N of the polyparaxylylene is, for example, N = 5000 or more, but is not limited thereto.

At the time of the vapor deposition, the silane treatment is performed in advance on the iron core 31 having the surface of the iron core material plated with copper-nickel or the like. In the case where the silane coupling agent is not used and the polyparaxylylene coating 31a is directly applied to the iron core 31, the polyparaxylylene coating 31 is not suitable for the iron core 31.
The film thickness of “a” may vary, and in particular, in the corner portion of the iron core 31 having the bent portion in the present embodiment, the same figure (c)
As shown in (3), the film thickness was thin, and it was not possible to obtain a stable and uniform film thickness.

On the other hand, when the silane treatment of this time is performed, that is, when a silane coupling agent is used, this acts as an adhesive between the two and enhances the bonding strength between the polyparaxylylene vapor deposition film and the iron core 31. In addition, the coating 31a having a uniform and stable film thickness can be provided even in a bent portion having a complicated shape.

According to the vapor deposition method, workability is excellent, for example, because processing by a barrel is possible, and therefore cost efficiency is good. Pinholes are less likely to occur. In particular, when the polyparaxylylene used this time is used, the advantage of the vapor deposition is great. In addition, polyparaxylylene has an advantage that winding is easy because the vapor-deposited film has a good slip property. As an example of the characteristics of the vapor-deposited coating of the iron core according to the present invention, the volume resistance is about 8.8 × 10 ¹⁶ Ω · cm and the melting temperature is about 280 ° C.

FIG. 3 shows an example of a polarized relay using the iron core for an electromagnet according to the present invention. In the figure, 1
Is a casing, which is a cover 11 that is covered with a base 11 made of an insulating material such as synthetic resin and a side wall of the base 11.
And a coil block 3 in the casing 1.
The magnet piece 4 and the armature block 5 are arranged. The base 11 has a box-like shape opened upward as viewed in the figure. The base 11 is provided with walls 14 to which fixed contact plates 24 having fixed contacts 23 are fixed at four inner corners. Contact piece 2
1 and common terminal piece 22, fixed contact plate 24 and fixed terminal piece 2
5, and coil terminal coupling piece 26 and coil terminal piece 27
Are formed integrally with a conductive plate,
These are integrally formed with the base 11 by insert molding.

Like the base 11, the cover 12 is made of an insulating material such as synthetic resin, and has a box-like shape that opens downward as viewed in the drawing. The cover 12 has four insulating layers extending downward from the inner peripheral surface of the upper wall. A sex partition 16 is provided in a protruding manner.

The partition 16 is formed along the longitudinal direction of the cover 12, and in the state where the coil block 3, the magnet piece 4 and the armature block 5 are housed in the casing 1, the armature 51 is formed.
Is inserted between the movable contact spring piece 52 and the movable contact spring piece 52 so that a large insulation distance can be secured between them.

The coil block 3 has a coil 32 wound around a horizontal piece of a substantially U-shaped iron core 31 opened upward, a coil terminal 34 as an end of the coil 32, and a coil terminal coupling piece 26.
The coil terminal piece 27 is connected to the coil terminal 34 via the. It goes without saying that a vapor deposition coating 31a of polyparaxylylene is formed on the surface of the iron core 31.

The magnet piece 4 has a plate-like shape, and a recessed groove 4 having a substantially semicircular cross section and running in the width direction of the base 11 at the center of the upper surface in the figure.
1 is formed. The upper surface of the magnet piece 4 has the largest thickness in the central portion of the base 11 in the longitudinal direction, and the inclined surface 4 is inclined such that the thickness gradually decreases toward the ends.
It is 2. Further, both ends of the magnet piece 4 in the longitudinal direction of the base 11 are magnetized to the same pole, and the central portion is magnetized to a different magnetic pole.

The armature block 5 is made of a magnetic material and is formed in the shape of a substantially rectangular flat plate, and a movable contact spring disposed on the same plane as the armature 51 on both sides in the width direction of the armature 51. Piece 52, armature 51 and movable contact spring piece 5
2 and a spring support body 53 which is a molded product of an insulating material such as a synthetic resin integrally molded. The spring support 53 is formed with notches 57 that open at both edges of the armature 51 in the width direction. This notch 5
A support piece 55 is provided so as to project from the innermost end of 7, and the tip end portion of the support piece 55 projects outwardly beyond the spring support body 53 in the width direction of the armature 51.

That is, since the movable contact spring piece 52 is fixed by the spring support body 53 at the central portion in the longitudinal direction, and the support piece 55 is projected from the spring support body 53, the movable contact spring piece 52. Both ends in the longitudinal direction and the support piece 55 independently apply a spring force.

The general operation of this relay will be described. When the coil 32 is energized, one end of the armature 51 in the longitudinal direction is attracted by one leg of the iron core 31 according to the direction of magnetization, and the armature block 5 swings, so that the iron core 31 → armature 51 → magnet. A closed magnetic circuit is formed from the piece 4 to the iron core 31, and the movable contact spring piece 5 is formed.
One end in the longitudinal direction of 2 contacts the corresponding fixed contact 23. When the power supply to the coil 32 is stopped in this state,
The closed magnetic circuit is maintained as it is due to the magnetic force of the magnet piece 4,
The armature 51 is kept in contact with one of the iron cores 31. Further, if the energization direction to the coil 32 is reversed,
The armature 51 is attracted to the other leg piece of the iron core 31, and the other end portion of the movable contact spring piece 52 in the longitudinal direction comes into contact with the corresponding fixed contact 23. After the power supply is stopped in this state, the state is maintained as it is, so that a so-called bistable operation is performed. Alternatively, it is possible to perform monostable operation.

The application of the iron core for an electromagnet according to the present invention is not limited to this.

[0026]

EFFECTS OF THE INVENTION The iron core for electromagnets according to the present invention has a very high adhesion between the polyparaxylylene and the iron core, which is obtained by subjecting the iron core to a silane treatment with a vapor-deposited coating on the surface thereof. Since it is possible to obtain a stable coating, it is possible to obtain a uniform and stable coating even in the bent portion of the iron core having a bent portion with a complicated shape.
A stable coating film of polyparaxylylene can be obtained.

Therefore, stable insulation can be obtained even with a thin film thickness, and the unevenness of the coil winding due to the variation in film thickness is eliminated, so that a stable winding can be achieved.

Further, since the film thickness is excellent in uniformity, it is possible to accurately and easily secure the residual gap of the magnetic pole surface of the iron core when it is used for a relay, and it is also possible to stabilize the operating characteristics.

[Brief description of drawings]

FIG. 1 (a) is a front view showing an embodiment of an iron core for an electromagnet according to the present invention, FIG. 1 (b) is an enlarged sectional view of the same, and FIG. 1 (c) is an enlarged view of a comparative example. Cross section,

FIG. 2 is an explanatory view showing an example of how to make an iron core for an electromagnet according to the present invention,

FIG. 3 is an exploded perspective view of a polarized relay using the iron core for an electromagnet according to the present invention,

[Explanation of symbols]

 31 iron core 31a polyparaxylylene vapor deposition film

Claims (1)

[Claims] 1. An iron core having both sides bent and a coil winding wound around an intermediate outer periphery to form an electromagnet,
An iron core for an electromagnet, which is obtained by subjecting a surface of the iron core to a silane treatment and then forming a vapor-deposited coating film of polyparaxylylene.