JPS63206151A - Linear pulse motor - Google Patents

Abstract

PURPOSE:To obtain a stable thrust in a linear pulse motor by disposing a bypass magnetic path formed of a soft magnetic material between magnetic paths to reduce magnetic interference between magnetic fields generated by coils. CONSTITUTION:A bypass magnetic path 18 is formed of a soft magnetic material in the same length as those of magnetic paths 6, 7 in the heights of permanent magnets 13, 14, i.e., in the same width as the size of a direction of an arrow. A movable element 12 is formed by securing in series the magnets 13, 14 to both sides of both edges of the path 18 so that the flowing directions of the bypass magnetic fluxes become the same, and by magnetically coupling poles 6-1, 6-2 and 7-1, 7-2. With this configuration, even if exciting magnetic fields generated by the paths 6, 7 and coils 5-1, 5-2 become reverse, the magnetic flux tending to creep from one path 6 or 7 to the other 7 or 6 flows in the path 18. Accordingly, magnetic interference between the magnetic fields generated by the coils 5-1, 5-2 can be reduced.

Description

[Detailed Description of the Invention] [Summary] A bypass magnetic path is constructed between a part where one pair of permanent magnets is connected in series and a part where the other pair of permanent magnets are connected in series, and one permanent magnet and Stable thrust is made possible by a mover that forms a magnetic path that magnetically couples magnetic poles in which bias magnetic flux flows in the same direction from the other permanent magnet using an electromagnet equipped with an excitation coil.

[Industrial application field]

The present invention relates to linear pulse smoke.

In particular, permanent magnet type linear pulse motors (hereinafter referred to as linear pulse motors) are capable of open-loop positioning and are easy to maintain. It is used as an access motor for disks.

Recently, these devices have become even more compact, and along with this, linear pulse motors need to be smaller as well as other electronic components. There is a need for a linear pulse motor that can reduce and provide stable thrust.

[Conventional technology]

As shown in Figure 2, the linear pulse smoke that has been widely used in the past has two electromagnets with excitation coils 5-1 and 5-2 wound around the center, and an excitation magnet for the electromagnets. By combining the permanent magnets 3 and 4 that have substantially the same flux density in a square shape when viewed from above, the magnetic poles 6-1, 6-2, and 7-1 whose bias magnetic flux flows in the same direction due to the permanent magnets 3 and 4 are formed. Magnetic paths 6 and 7 are configured to magnetically couple 7-2 with an electromagnet equipped with an excitation coil.

And the magnetic poles 6-1, 6-2.7-1, 7-2
On each surface facing the stator 1, magnetic pole teeth are provided at a constant pitch perpendicular to the direction of the magnetic paths 6 and 7, and the magnetic pole teeth of the magnetic pole 7-1 are in phase with the magnetic pole teeth of the magnetic pole 6-1. form,
The magnetic pole teeth of the magnetic poles 6-2 and 7-2 are formed with a phase relationship shifted by half the tooth pitch, and two rollers (not shown) are arranged on the magnetic pole tooth side to maintain a constant distance between them and the stator l. It is constructed to be spaced apart.

On the other hand, the stator 1 has two rows of stator teeth 1a, lb with the same pitch as the magnetic pole teeth, and a magnetic pole? The stator teeth 1b opposite to -1 and 7-2 are shifted in phase by 1/4 of the tooth pitch.

The method for driving the movable element 2 is as shown in (a) of the developed view shown in FIG. When magnetized,
The magnetic pole 6-1 becomes the N pole due to the magnetic flux of the permanent magnet 3 and the magnetic flux of the coil 5-1, and the magnetic pole 7-1 becomes the S pole due to the magnetic flux of the permanent magnet 3 and the coil 5-2.
The magnetic poles 6-2 and 7-2 are not magnetized because the magnetic flux of the permanent magnet 4 and the magnetic flux of the coils 5-1 and 5-2 interfere with each other, so the stator facing the magnetic poles 6-1 and 7-1 The position is determined by the balance of the attractive force with the stator tooth of No. 1, and then, as shown in the figure (b1), when a current in the opposite direction is applied to the coil 5-1, the direction of the magnetic field is reversed, so that the magnetic pole 6- The magnetic force of 1 becomes O, the N pole is transferred to the magnetic pole 6-2, and the magnetic pole 6-2.7
-1, the stator teeth are attracted to each other and moved in the direction of the arrow by 1/4 of the tooth bit.

Next, coil 5-15 as shown in Figure 01 and Figure (d).
-2's excitation pattern is changed, magnetic poles 6-2 and 7-2.
Since the magnetic poles 6-1 and 7-2 change and step by 1/4 pitch, the magnet moves to a designated position by changing the excitation pattern a predetermined number of times.

[Problem that the invention seeks to solve]

The problem with the conventional linear pulse motor described above is the spacing between the two magnetic paths 6 and 7 in which the permanent magnets 3 and 4 are thinly combed and the excitation coils 5-1 and 5-2 are arranged. By narrowing and downsizing the magnetic path 6., when the magnetic fields generated by the two coils 5-1, 5-2 are in the same direction, only one magnetic path 6. or 7 to the other magnetic path 7. Or the magnetic flux does not go around to 6, but
Reverse direction 1 For example, in the case shown in Fig. 3 (a) or (C), the magnetic flux wraps around each magnetic path 6 and 7, and the magnetic flux is saturated in the magnetic paths 6 and 7. The point is that the interference of

Therefore, the thrust force varies depending on the direction of the magnetic field generated by the coils 5-1 and 5-2, which deteriorates the positioning accuracy. In addition, increasing the cross-sectional area so that the magnetic path 6.degree.

In view of the above-mentioned situation, the present invention aims to provide an inexpensive linear pulse smoke that minimizes the wraparound of magnetic flux from one magnetic path to the other magnetic path.

[Means for solving problems]

As shown in FIG.
A bypass magnetic path 18 made of soft magnetic material connects 4 in series.
t, magnetic poles 6-1 and 6-2, and magnetic poles 7-1 and 7-2 in which the bias magnetic flux flows in the same direction from one permanent magnet 13 and the other permanent magnet 14 are magnetically coupled. The linear motor of the present invention combines a movable element 12 in which magnetic paths 6 and 7 are formed and excitation coils 5-1 and 5-2 are wound around the center of the magnetic paths 6 and 7, and a stator 1 having a conventional structure. Solved by Pulsmoke.

[Effect]

That is, in the present invention, by arranging the bypass magnetic path 18 formed from a soft magnetic material between the magnetic paths 6 and 7,
When the magnetic fields generated by the excitation coils 5-1 and 5-2 are in opposite directions, one magnetic path 6. or from 7 to the other magnetic path 7
．． Or, since the magnetic flux that tries to go around to coil 6 flows through bypass magnetic path 18, magnetic interference between the magnetic fields generated in coils 5-1 and 5-2 is reduced, stable thrust is obtained, and positioning accuracy is improved. It becomes possible.

〔Example〕

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 shows a perspective view of the linear pulse motor according to this embodiment. In the figure, the same members as in FIG. , 13-1.13-2 and 14-1.14-2 are permanent magnets that flow bias magnetic flux, and 18 is a bypass magnetic path that reduces magnetic interference between magnetic fields.

FIG. 1 shows a perspective view of the linear pulse motor according to this embodiment.
．． 14 is a magnetic path 6. when two pieces are connected in series. Or, it is a magnet with a rectangular cross section having a magnetic flux density approximately equal to the excitation flux density of 7.

The bypass magnetic path 18 is made of a soft magnetic material and has the same width as the height of the permanent magnets 13, 14, that is, the dimension in the arrow direction, and the same length as the magnetic paths 6 and 7.

To construct the mover 12 using the above-mentioned members, permanent magnets 13 and 14 are arranged in series on both sides of both ends of a bypass magnetic path 18 formed from a soft magnetic material so that the bias magnetic flux flows in the same direction. Fixed and excitation coils 5-1 and 5 in the center
The two magnetic paths 6 and 7 wound with -2 are fixed in a holiday shape on the upper surface, and the magnetic poles 6-1 and 6-2 and 7-1 and 7-2 are magnetically coupled.

Next, as in the conventional case, each magnetic pole 6-1,
6-2, 7-1, and 7-2 are provided with magnetic pole teeth at a constant pitch on the surfaces facing the stator 1, and the magnetic pole teeth are arranged at a constant pitch with respect to the magnetic pole teeth of the magnetic pole 6-1. -1 magnetic pole teeth are formed in the same phase, magnetic poles 6-2 and 7-2
The magnetic pole teeth are formed in a phase relationship shifted by half the tooth pitch, and two rollers (not shown) are provided on the magnetic pole tooth side to maintain a constant distance from the stator 1. .

With the above structure, the coils 5-1 and 5-2 of the magnetic paths 6 and 7
Even if the excitation field generated in the magnetic field is in the opposite direction, one magnetic path 6
．． or 7 to the other magnetic path 7. Or, the magnetic flux that tries to go around to coil 5-1 flows through bypass magnetic path 18.
, 5-2, stable thrust can be obtained by reducing the magnetic interference between the magnetic fields generated in step 5-2.

[Effects of the Invention] As explained above, according to the present invention, the magnetic flux generated by the coils arranged in parallel with each other flows through the bypass magnetic path with an extremely simple configuration, reducing magnetic interference between the respective magnetic fields and achieving stable thrust. It is expected to have the effect of significantly improving reliability, and is extremely useful industrially.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a linear pulse motor according to an embodiment of the present invention, FIG. 2 is a perspective view showing a conventional linear pulse smoke, and FIG. 3 is a diagram showing the running principle of a linear pulse smoke. In the figure, 1 is a stator, la, lb are stator teeth 5-1, 5-2 are coils, 6.7 is a magnetic path, 6-16-27-17-2 is a magnetic pole, 12 is a mover, 13 , 14 is a permanent magnet, 18 is a bypass magnetic path.

Claims (1)

[Claims] Magnetic poles (6-1) and (6-2), (7-1) and (7-2) in which the bias magnetic flux due to the permanent magnet flows in the same direction.
In a linear pulse motor in which a magnetic path (6, 7) is formed which is magnetically coupled by electromagnets equipped with coils (5-1, 5-2), the permanent magnets (13, 14) are connected by connecting multiple magnets in series. The magnet is connected to one permanent magnet (13
A soft magnetic bypass magnetic path (
18) A linear pulse motor characterized by being provided with.