JPH04271103A - Electromagnetic device equipped with permanent magnet - Google Patents

Abstract

PURPOSE:To improve the sensitivity of an electromagnetic device, by adding a permanent magnet to the electromagnetic device constituted of a closed magnetic circuit with a coil, and effectively taking-out the energy of the permanent magnet. CONSTITUTION:Figure (a) shows an example used for an inductor. The internal reluctance of a permanent magnet 4 and the external reluctance of the permanent magnet 4 (which contains the reluctance of a nonmagnetic member 6 and the reluctance of a closed magnetic path 1) are adjusted by adjusting the size of a nonmagnetic member 6, and high sensitivity is realized. Figure (b) shows an example used for an electromagnet. The internal reluctance of the permanent magnet 4 and the external reluctance of the permanent magnet 4 (which is the combined value of the reluctance of the nonmagnetic member 6 and the reluctance of the closed magnetic path 1) are adjusted by adjusting the size of the nonmagnetic member 6.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention exhibits high sensitivity characteristics by superimposing magnetic flux caused by coil energization and magnetic flux caused by a permanent magnet on a common closed magnetic path. Concerning electromagnetic devices such as inductors, transformers, or electromagnets.

0002

BACKGROUND OF THE INVENTION Conventionally, a wide variety of electromagnetic devices have been used in a wide range of fields, but generally a coil 2 wound around a closed magnetic path 1 is energized as shown in the schematic diagram of FIG. 7(a). 2. Description of the Related Art There are known inductors that utilize self-induction due to changes in current, or transformers that utilize mutual induction that acts on a secondary winding wound around a closed magnetic circuit (not shown). In addition, as shown in FIG. 7(b), the coil 2 wound around the closed magnetic path 1 formed by the fixed piece 1a, the movable piece 1b, and the operating gap 1c is energized to attract the movable piece 1b to the fixed piece 1a. Electromagnets and the like are well known, but none of them are equipped with a permanent magnet and utilize the magnetic flux 3 generated by energizing a coil.

[0003] The present inventor has proposed an electromagnetic actuator (patent application 1986-5) as an example of an electromagnetic device equipped with a permanent magnet.
No. 02420) filed on June 4, 1985, we proposed an electromagnetic actuator that exhibits high sensitivity characteristics.

0004

Problems to be Solved by the Invention The present invention improves the above-mentioned prior art, and by effectively arranging permanent magnets, it is possible to improve not only electromagnets but also general electromagnetic devices such as inductors and transformers using permanent magnet porcelain. The goal is to make effective use of energy, make electromagnetic devices more sensitive, smaller and lighter, and reduce manufacturing costs.

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention employs the following technical means.
It consists of a closed magnetic path, ■ a coil that is wound around the closed magnetic path and is energized, and ■ a permanent magnet that bridges the closed magnetic path through a non-magnetic material for reluctance adjustment, and by adjusting the dimensions of the non-magnetic material. , a permanent magnet characterized in that high sensitivity is achieved by adjusting the internal reluctance of the permanent magnet and the reluctance of the external magnetic path (reluctance of a closed magnetic path including a non-magnetic material) as seen from the magnetic pole surface of the permanent magnet. It is an electromagnetic device equipped with

Further, the above-mentioned closed magnetic path may be a closed magnetic path of an electromagnet comprising a magnetic fixed piece and a magnetic movable piece facing the fixed piece end face with a predetermined operating gap therebetween.

[0007]

[Operation] The operation of the present invention will be explained with reference to the drawings. First, FIG. 4(a) is a schematic structural diagram of an inductor for explaining the operation of the present invention, in which a magnetic closed magnetic path 1, a coil 2, a magnetic flux 3 induced by energizing the coil 2, a permanent magnet 4, a permanent magnet It is composed of magnetic flux branches 5a and 5b, and a non-magnetic material 6 for adjusting reluctance. (If the primary and secondary windings are drawn in the closed magnetic path shown in the figure, it becomes the configuration of a transformer.) Here, ignoring the leakage and nonlinearity of the magnetic path and the loss of magnetomotive force in the magnetic body, the coil Assuming that the magnetic flux 3 due to energization is a sinusoidal alternating magnetic flux, the magnetic fluxes 5a and 5b of the permanent magnets in the magnetic path and the magnetic flux 3 due to coil energization are superimposed, which can be explained using the graph of FIG. 5.

FIG. 5 is a graph in which the vertical axis shows magnetic flux and the horizontal axis shows the passage of time. The clockwise flow of magnetic flux is expressed as positive, and the counterclockwise flow is expressed as negative. In other words, if the maximum value of the sinusoidal alternating magnetic flux due to coil energization is equal to the shunt magnetic flux of the permanent magnet, the composite magnetic flux of the closed magnetic path will be the composite line shown, which is a sine wave with twice the amplitude of the alternating magnetic flux due to coil energization only. It will be excited.

That is, according to the present invention, compared to the prior art, it is possible to induce a large magnetic flux change in a closed magnetic circuit with a small excitation ampere turn by effectively utilizing the magnetic energy of a permanent magnet. This makes it possible to manufacture highly sensitive electromagnetic devices. Next, the action of the non-magnetic material 6 shown in FIG. 4(a) will be explained using the demagnetization curve of the permanent magnet shown in FIG. As is well known, if a non-magnetic material is inserted into a part of the magnetic path of a permanent magnet, the operating point of the permanent magnet will be on the demagnetization curve at the intersection S (
It operates on the recoil line that passes through the initial operating point). and,
When the condition that the internal reluctance and external reluctance of the permanent magnet are equal is established, the magnetic energy given to the load from the permanent magnet becomes maximum. The present invention utilizes this principle, and the closed magnetic circuit 1 of the electromagnetic device having the configuration shown in FIG.
In order to effectively superimpose the magnetic fluxes 5a and 5b from the permanent magnets 4 on the closed magnetic circuit 1 according to the condition of the reluctance value of It is necessary to match the observed internal reluctance and external reluctance of the permanent magnet.

Next, FIG. 4(b) is a schematic diagram of an electromagnet for explaining the operation of the second invention. That is, magnetic fluxes 5a and 5b of permanent magnets and magnetic flux 3 caused by coil energization are superimposed on a closed magnetic path 1 consisting of a fixed magnetic piece 1a, a movable magnetic piece 1b, and an operating gap 1c, and the magnetic flux 3 is made to act as a highly sensitive electromagnet. By adjusting the dimensions of the non-magnetic material 6, the internal reluctance of the permanent magnet 4 and the external magnetic path of the permanent magnet including the operating gap 1c are matched.

[0011]

Embodiment FIGS. 1, 2, and 3 show explanatory diagrams of embodiments of the present invention. First, FIG. 1 shows a cylindrical magnetic body 7a with one end closed, a flanged cylindrical magnetic body 7b, a coil 2, a permanent magnet 4 magnetized in the axial direction, and a cylindrical non-magnetic body 6 with one end closed.
The electromagnetic device of the first embodiment is composed of a disc-shaped magnetic material 7, and can be used in ultra-small, highly sensitive reactors, transformers, etc., and is suitable for mass production.

FIG. 2 shows a closed magnetic path consisting of a fixed iron core 9, a cylindrical yoke 10 with one end closed, a disk yoke 10a, and a movable iron core 11, a coil 2, and a disk-shaped magnetic pole piece 12 connected to the fixed iron core 9. , and a donut-shaped permanent magnet 4 with axial magnetization.
This electromagnetic device according to the second embodiment of the present invention is constructed of a cylindrical non-magnetic material 6 with one end closed, and can be used in a highly sensitive plunger type electromagnet with latching action and is suitable for mass production. Here, 13 is the operating gap, and the operating gap 1
The illustration of the spring disposed at 3 is omitted.

Furthermore, FIG. 3 shows a third embodiment of the present invention, which is an example in which the sensitivity of an ultra-small electromagnetic relay or the like is increased. It is composed of a fixed iron core 9, a coil 2, a permanent magnet 4, a yoke 10, a movable iron core 11, a non-magnetic body 6, a spring 8, an operating gap 13, and the like. Note that 14 is a fulcrum.

[0014]

According to the present invention, compared to the prior art, it is possible to exhibit a highly sensitive operating characteristic that operates with a minute excitation ampere turn, so that the following excellent effects can be achieved. ■Enables the development of mechatronics products using minute power sources such as dry batteries. ■It allows the coils of electromagnetic devices to be made lighter and smaller.

(2) Significant cost savings due to the reduction in the amount of copper in the coil. These direct effects, recent advances in permanent magnetic materials, and developments in mass production technology have facilitated the development of microelectromagnetic devices, which can greatly contribute to the fields of electronics and mechatronics.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an inductor according to a first embodiment of the present invention, FIG. 1(a) is a longitudinal cross-sectional view, and FIG. 1(b) is a diagram of FIG. 1(a).
FIG.

FIG. 2 is an explanatory diagram of a plunger type electromagnet according to a second embodiment of the present invention, in which FIG. 2(a) is a longitudinal cross-sectional view, and FIG. 2(b) is a view taken along the line BB in FIG. 2(a). FIG.

FIG. 3 is an explanatory diagram of an electromagnetic relay according to a third embodiment of the present invention, FIG. 3(a) is a longitudinal cross-sectional view, and FIG. 3(b) is a diagram of FIG. 3(a).
It is a CC arrow view of FIG.

FIG. 4 is a schematic diagram showing the configuration of the present invention, and FIG. 4(a)
is an inductor, and FIG. 4(b) is an electromagnet.

FIG. 5 is a graph explaining the effect of the present invention.

FIG. 6 is a demagnetization curve diagram of a permanent magnet, explaining the effect of the present invention.

FIG. 7 is an explanatory diagram of a conventional example, with FIG. 7(a) showing an inductor and FIG. 7(b) showing an electromagnet.

[Explanation of symbols]

1 Closed magnetic circuit 1a Fixed piece 1b
Movable piece 1c Operating gap 2 Coil 3 Magnetic flux (by energization) 4 Permanent magnets 5a, 5b Magnetic flux (by permanent magnet) 6 Non-magnetic material 7, 7a, 7b Magnetic material 8 Spring 9 Fixed core 10, 10a Yoke 11 Movable core 12 Magnetic pole Piece 13 Operating gap 14 Fulcrum

Claims (2)

[Claims] 1. A magnet comprising a closed magnetic path formed of a magnetic material, a coil wound around the closed magnetic path and energized to excite it, and a permanent magnet bridging the closed magnetic path via a non-magnetic material. An electromagnetic device equipped with a permanent magnet, characterized in that a magnetic flux caused by the energization of the coil and a magnetic flux caused by the permanent magnet act in a superimposed manner. 2. An electromagnetic device equipped with a permanent magnet according to claim 1, wherein said closed magnetic path is composed of a magnetic fixed piece and a magnetic movable piece facing an end face of said fixed piece with a predetermined operating gap therebetween.