JPH01160348A - Linear pulse motor - Google Patents

Abstract

PURPOSE:To call for no electromagnets to a moving piece and to make the moving piece lightly weighed, by magnetizing pole teeth to the polarity in accordance with the input pulse and by moving the moving piece on a straight line with the magnetic action between the magnetized pole teeth and the poles of permanent magnets provided to the moving piece. CONSTITUTION:A linear pulse motor is composed of a stator 11 and a moving piece 12. The stator 11 is formed by installing a pair or exciting units 14 and 15 to a supporting body 13. The exciting units 14 and 15 are formed by installing pole plates 18 and 19 to the tips of both side walls of a yoke 16 around which an exciting coil 17 is wound. The pole plates 18 and 19 have comb-toothed pole teeth 18a, 19a, 20a and 21a. The moving piece 12 has wheels 26 provided to both the front and rear ends of a moving piece main body 24 and permanent magnets 27 and 28 installed to the surface on the stator 11 side.

Description

[Detailed description of the invention] [Industrial application field] do.

[Conventional technology]

FIG. 7 shows a conventional linear pulse motor, in which 1 is a stator on which rack-shaped pole teeth 1a are formed;
2 is a movable element. The movable element 2 has magnetic poles I made of soft magnetic steel, each having a pole tooth a formed at the lower end thereof, which faces the pole tooth 1a.
It is formed by attaching permanent magnets 4a*4b to electromagnets 3a and 3b formed by winding excitation coils b1 to b4' every ~■, and connecting each permanent magnet 4ar to 4b with a yoke 5.

Wheels 6 are attached to both ends of the movable element 2 in the front and rear directions, respectively.

In a linear pulse motor with such a configuration, the magnetic pole ■
, ■ Excitation coil b3. Excite b4,
By generating a magnetic flux that circulates around the electromagnet 3b in a clockwise direction, the permanent magnet 4b and the magnetic flux generated by the excitation current are added to each other at the magnetic pole ■, and the permanent magnet 4b is generated at the magnetic pole ■.
and the magnetic flux due to the excitation current subtract from each other. For this reason, the magnetic pole
A magnetic attraction force is exerted between the pole tooth a of the stator 1 and the pole tooth 1a of the stator 1 that opposes the pole tooth a, and the movable element 2 is moved by one step. Next, excitation is switched to excitation coils bl and b2.

Then, the pole tooth a of the magnetic pole ■ and the stator 1 facing it
A magnetic attraction force acts between the movable element 2 and the pole tooth 1a, and the movable element 2 is further moved by one step. Thereafter, by similarly switching the excitation phase and polarity, the movable element 2 can be linearly moved along the stator 1 according to the number of input pulses.

[Problem that the invention seeks to solve]

According to the conventional motor described above, the movable element 2 is
The movable element 2 was large and heavy because it was formed with electromagnets 3a and 3b formed by winding excitation coils bl-b4 around each of the magnetic poles I to 1 made of soft magnetic steel, which accounted for most of the magnetic poles. Therefore, since the inertia of the movable element 2 is large, there are problems in that the responsiveness is not good and the vibration is large and the damping characteristics are not good.

Furthermore, since the excitation coils bl-b4 are provided on the mover 2, it is troublesome to handle the lead wires, and the magnetic poles are made of soft magnetic steel! Since the machining process to create the pole tooth a at the lower end of ~■ is also troublesome, there is also the problem of high manufacturing cost.

Therefore, an object of the present invention is to provide a narrow, inexpensive linear pulse motor that can improve the responsiveness and damping characteristics of a mover, simplify lead wire processing, and generate less vibration due to excitation. It's about doing.

[Means for solving problems]

In the present invention, an elongated stator is configured to have a pair of excitation units that are continuous along the length direction.

These pair of excitation units are provided with a large number of pole teeth arranged at a pitch four times the amount of one pulse movement of a movable element which is provided facing the stator and is movable along the length direction of the stator. two magnetic pole plates having a comb-like shape,
These magnetic pole plates are formed from an elongated yoke attached with the pole teeth staggered and an excitation coil wound around the yoke along its length. Furthermore, the movable element provided across the pair of excitation units has a permanent magnet, and the magnetic pole surface of the permanent magnet is
By arranging the movable elements alternately along the moving direction of the movable element at a pitch approximately twice the amount of one-pulse movement of the movable element, and by arranging these magnetic pole faces closely facing the magnetic pole plates of the stator, the conventional This solves the problem.

[Effect]

The linear pulse motor according to the present invention is used by passing winding current through the excitation coils of a pair of excitation units provided in the stator to excite each excitation unit, and by excitation of one excitation coil, the excitation coils equipped with this coil are excited. The pole teeth of a set of magnetic pole plates of the unit are each magnetized to a different polarity. Since the magnetic pole surface of the mover is closely opposed to the magnetic pole plate of the stator, the poles of the excited magnetic pole plate are The movable element is moved by a predetermined step amount along the length direction of the stator according to the number of input pulses by the magnetic force acting between the teeth and the magnetic pole surface of the permanent magnet included in the movable element. The movable element is used to directly drive a light load such as a thermal head of a printing device or a disk drive seek device of a floppy disk drive.

As described above, the pole teeth of the stator are magnetized to the polarity according to the input pulse, and the movable element is moved linearly by the magnetic action of this and the magnetic pole of the permanent magnet provided on the movable element. , there is no need to provide an electromagnet in the mover. Therefore, the weight of the mover can be reduced, and its inertia can be reduced.
Lead wires for the mover can be omitted.

Furthermore, since the excitation coil is provided on a large stator rather than a small mover, it is easy to wind the coil, and the excitation coil only needs to be wound once for each excitation unit. There is no need to create a large number of pole teeth by machining, and a magnetic pole plate having these pole teeth can be easily manufactured by punching a magnetic plate such as a silicon steel plate using a press.

Moreover, since the pair of excitation units are arranged in succession along the length direction, when these units are installed side by side, a linear pulse motor with a narrow width can be constructed, and the pole teeth of the magnetic pole plate and the magnetic pole surface of the permanent magnet can be The action of attracting the mover toward the stator due to the magnetic attraction force acting between the two can be applied evenly across the entire width of the mover, and as the excitation is switched, the action of attracting the mover toward the stator can be applied alternately to one side of the mover in the width direction as the excitation is switched. The mover is not attracted to the stator side.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 6.

Reference numeral 11 in FIGS. 1 and 2 is an elongated stator, and reference numeral 12 in the same figure is a movable member that is provided opposite to the stator 11 and is movable along the length direction of the stator 11. It is. A linear pulse motor is formed from these stator 11 and movable element 12.

The stator 11 has a length corresponding to the moving distance of the movable element 12, and a pair of excitation units 14 and 15 are connected to a support 13 made of a non-magnetic material such as synthetic resin in a continuous manner in the length direction. It is installed and formed like this. Illustrated support 13
has upward side walls on both sides of the bottom wall, forming a substantially U-shape. This support 13 has a pair of escape grooves 13a formed along its length on the inner surface of its bottom wall, and rails 13b are provided along its length on both side walls. The rail 13b is formed of a metal flat plate or the like.

As shown in FIG. 1, the excitation unit 14 winds an excitation coil 17 along the length of the bottom wall of an elongated yoke 16 made of a magnetic material such as soft magnetic steel into a groove shape. It is formed by attaching magnetic pole plates 18 and 19 to the tips of the walls, respectively. The two magnetic pole plates 18 and 19 are each made of a magnetic material, and the one shown is obtained by punching out a thin silicon steel plate using a press. Each of these magnetic pole plates 18, 19 has a large number of pole teeth 18a*19.
The pole teeth 18a have a comb-like shape.

They are attached to the yoke 16 with the comrades 19a inserted alternately. Then, the pitch A1 of each pole tooth 18a is
and the pitch A of the pole teeth 19a are respectively the movable member 1
It is set to be four times the one-pulse movement amount B of 2 (see FIG. 3).

Further, the other excitation unit 15 is the excitation unit 14
As shown in FIGS. 1 and 2, it has a large number of pole teeth 20a and 21a arranged at a pitch A that is four times the one-pulse movement QB of the movable element 12, and has a comb-like shape. Eggplant 2
The two magnetic pole plates 20 and 21 are attached to the elongated yoke 22 (see Fig. 2) with their pole teeth 20a and 21a inserted alternately, and the excitation coil 23 (see Fig. 2) is attached to the yoke 22 along its length. (see Figure 2).

A spacer 30 is interposed between the pair of excitation units 14 and 15. The thickness t of this spacer 30 is a thickness that is an integral multiple of the one-pitch movement amount B of the movable element 12, and by using such a spacer 30, the pair of excitation units) 14 and 15 can be and the pole tooth 20a, and the pole tooth 19a and the pole tooth 21a,
A pair of excitation units 14, 15 and the movable element 12 have the same magnetic relationship as when they are arranged side by side inside the support body 13, shifted by the same pitch as the one-pitch movement amount B of the movable element 12, respectively.
It is designed to be formed between.

Note that a gap may be provided instead of the spacer 30.

The movable element 12 is provided over a pair of continuous excitation units 14, 15 along its length. The movable element 12 is provided with support structures at both front and rear ends of a movable element main body 24 made of a non-magnetic material such as synthetic resin. This support structure includes an axle 25 rotatably attached to the mover body 24.
and wheels 26 attached to both left and right ends of the axle 25, respectively. The wheel 26 is in rolling contact with the rail 13b, and is provided with a flange 26a that engages with the side surface of the rail 13b to prevent the mover 12 from falling off from both the left and right sides of the stator 11. There is.

A permanent magnet 27 that closely opposes the magnetic pole plates 18a and 19a of the excitation unit 14 is attached to the surface of the movable element body 24 on the stator 11 side.
Permanent magnet 28 closely facing magnetic pole plates 20a and 21a of No. 5
is installed. Pole faces 27a of these permanent magnets 27,28.

28a are provided with different poles arranged alternately along the moving direction of the movable element 12, and the pitch C between the permanent magnets 27 and the pitch C between the permanent magnets 28 are an abbreviation of the one-pulse movement amount B of the movable element 12. It is set to double. For this reason, in the illustrated example, a plurality of permanent magnets 27.degree. 28 having a width twice the one-pulse movement amount B are arranged in parallel. Here above 1
Approximately twice the pulse travel pitch means not only when it is exactly twice as shown in the illustrated example, but also when the thrust applied to the mover 12 is not significantly impaired in practice. Even if it is slightly larger or smaller than twice, it is included. In addition, 2 in Figures 1 and 2
9 is a yoke.

The linear pulse motor having the above configuration is operated, for example, by two-phase bipolar drive by switching the excitation phase and polarity as shown in the following table. In the following table, x and x' indicate the excitation phases formed by the magnetic pole plates 18 and 19 of the excitation unit 14, and Y and Y' indicate the excitation phases formed by the magnetic pole plates 2 and 19 of the excitation unit 15.
0.21 indicates the excitation phase formed.

In other words, in step 1, the yoke 1
6 and 22 are excited simultaneously. Then, depending on the direction of the winding current, the magnetic pole plates 18, 20 are respectively magnetized to the north pole, and at the same time, the magnetic pole plates 19, 21 are magnetized to the south pole.

For this purpose, the pole teeth 18a of the magnetic pole plates 18, 19 are arranged in a staggered manner in one excitation unit 14.

19a generates magnetic forces of mutually different polarities, and
In the other excitation unit 15, magnetic forces of different polarities are also generated in the pole teeth 20a and 21g of the magnetic pole plates 20 and 21, which are provided in a staggered manner.

Therefore, in the state of step 1, as shown in FIG.
In Y, the pole teeth 18a, 20a magnetized to the N pole and the magnetic pole face 27a representing the S pole of the mover 12 are magnetically attracted to each other, and the excitation phase X formed by the magnetic pole plates 19 and 21 respectively
', Y', the pole teeth 19a, 21 magnetized to the S pole
a and the magnetic pole surface 28a representing the north pole of the movable element 12 are magnetically attracted to each other, and the movable element 12 is stabilized.

In the next step 2, the direction of the winding current with respect to the excitation coil 17 of the excitation unit 14 is reversed while leaving the excitation unit 15 as it is. Then, as shown in FIG. 4, the pole teeth 1 of the excitation phases x and x' formed by the magnetic pole plates 18 and 19
8a changes to the S pole and the pole tooth 19a changes to the N pole, so the pole tooth 1 in the excitation phases Y and Y' formed by the magnetic pole plates 18 and 19
8a and the polarity of the magnetic pole face 27a of the mover 12, and the polarity of the pole teeth 20a121a and the magnetic pole face of the mover 12 in the excitation phase formed by the magnetic pole plate 20.21. Due to the magnetic attraction acting between the polarity of the movable member 28a and the polarity of the movable element 28a, the movable element 12 is moved by one step ff1B in the direction of the arrow in FIG.

In step 3, leave the excitation unit 14 as it is,
The direction of the winding current for the excitation coil 23 of the excitation unit 15 is reversed. Then, as shown in FIG. 5, the polarities of the pole teeth 20a and 21a are changed, so that magnetic repulsion and attraction between the excitation unit 15 and the movable element 12 occur as in the case of FIG. 3 above. and excitation unit 1
4 and the movable element 12, the movable element 12 is moved by one step movement QB in the direction of the arrow in FIG.

In the final step 4, the direction of the winding current to the excitation coil 17 of the excitation unit 14 is reversed to the same direction as in step 1, while leaving the excitation unit 15 as it is. Then, as shown in FIG. 6, the pole teeth 13a,
Since the polarities of 19a are respectively changed, the magnetic repulsion/attraction action between the excitation unit 14 and the movable element 12 and the magnetic repulsion/attraction action between the excitation unit 15 and the movable element 12 as in the case of FIG. Due to the magnetic attraction action, the mover 12 is moved by one step movement amount B in the direction of the arrow in FIG.

Through steps 1 to 4 as described above, the movable element 12 can be linearly moved along the stator 11 according to the number of input pulses.

According to the linear pulse motor described above, the polarity of the stator 11 is set to the magnetic pole 18 according to the direction of the input pulse.
a to 21a, and the movable element 12 is moved linearly by the magnetic action of this and the magnetic pole faces 27a * 28a of the permanent magnets 27 and 28 provided on the movable element 12. There is no need to provide an electromagnet.

Therefore, the weight of the mover 12 can be reduced, and its inertia can be reduced. Therefore, the responsiveness of the movable element 12 can be improved, and the vibration of the movable element 12 can be reduced, so that the damping characteristics can be improved.

Furthermore, since the movable element 12 is not provided with an electromagnet, processing of lead wires for the movable element 12 can be omitted.

Although it is necessary to process the lead wires for the stator 11, this lead wire process on the stator 11 side can be easily performed.

Since the excitation coil 17.23 is provided on the large stator 11 instead of the small mover 12, this coil 17.
23 is easy to wind, and the excitation coil 17
．． 23 need only be wound once for each excitation unit 14.15. In addition to this, a large number of pole teeth 18a
There is no need to cut out the magnetic pole plates 18 to 21 of the stator 11 having a large number of pole teeth, and the magnetic pole plates 18 to 21 of the stator 11 having a large number of pole teeth can be easily manufactured by punching a magnetic plate such as a silicon steel plate using a press. can. Therefore, for these reasons, the motor can be manufactured at low cost.

Furthermore, by providing the excitation coils 17.23 on the stator 11, there are fewer restrictions on coil space compared to when the excitation coils 17.23 are provided on the mover 12, so required characteristics can be easily achieved. Correspondingly, the excitation coil 17.
23 can be provided.

In addition, in the linear pulse motor described above, since the pair of elongated excitation units 14 and 15 are continuous along the length direction, it is possible to construct a linear pulse motor with a narrower width than when these units 14 and 15 are arranged side by side. . Suitable for applications requiring narrow width.

At the same time, by making the pair of elongated excitation units 14 and 15 continuous along the length direction, the magnetic pole plates 18 to
The action of attracting the mover 12 toward the stator 11 by the magnetic attraction force acting between the pole teeth 18a to 21a of the permanent magnets 27 and 21 and the magnetic pole faces 27a and 28a of the permanent magnets 27 and 28 is
It works evenly across the entire width. In addition,
When a pair of excitation units are installed in parallel, when switching to excitation using the drive steps explained in the table above,
The action of attracting the mover 12 toward the stator 11 is
2 is applied alternately to each side in the width direction, and this alternate attraction causes the problem that the movable element 12 vibrates in the width direction due to a slight play between the axle shaft 25 and the wheel 26 due to the force. be. However, as described above, since the movable element 12 is attracted evenly over the entire width direction, the movable element 12
The movable element 12 can be moved smoothly by eliminating vibrations in the width direction of the movable member 12. Therefore, the light load such as a magnetic head directly driven by the movable element 12 is not vibrated, and the light load can be smoothly moved.

Although each of the embodiments described above is configured as described above, in the present invention, a pair of magnetic pole plates 18.19 or 20.21
may be formed on an insulating substrate by a printing technique or the like.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to reduce the weight of the mover, thereby increasing responsiveness and improving damping characteristics, and since no excitation coil is provided in the mover, lead wire processing is unnecessary. It is easy to do and can be manufactured at low cost. Furthermore, since the pair of excitation units are provided continuously in the length direction, the width can be made narrower, and vibrations in the width direction of the movable element can be eliminated to allow the movable element to move smoothly.

[Brief explanation of the drawing]

1 to 6 show one embodiment of the present invention, in which FIG. 1 is a perspective view showing a stator and a movable element separated from the stator, and FIG.
The figure is a cross-sectional view taken along the line ■--■ in FIG. 1, and FIGS. 3 to 6 are operation diagrams showing the magnetic relationship between the movable element and the stator in the order of driving steps. FIG. 7 is a vertical side view showing a conventional example. 11... Stator, 12... Mover, 14.15...
・Excitation unit, 16.22...Yoke, 19-21
...Magnetic pole plate, 19a-21a...Pole tooth, 17.23
... Excitation coil, 27.28 ... Permanent magnet, 27a
. 28a...Magnetic pole surface. Applicant's agent Patent attorney Takehiko Suzue Figure 3

Claims (1)

[Scope of Claims] A linear pulse motor comprising an elongated stator and a movable element provided opposite to the stator and movable along the length of the stator, wherein the stator has a length It has a pair of excitation units that are continuous along the direction, and these excitation units are arranged in a comb-like shape with a large number of pole teeth arranged at a pitch four times the amount of movement of one pulse of the movable element. Attach two magnetic pole plates to a long and narrow yoke with their pole teeth inserted alternately,
The yoke is formed by winding an excitation coil along its length, and the mover provided across the pair of excitation units has a permanent magnet, and the magnetic pole face of the permanent magnet is connected to the mover. The magnetic poles are arranged alternately along the moving direction of the movable element at a pitch approximately twice the amount of one pulse of movement, and the magnetic pole faces of the stator are closely opposed to the magnetic pole plates of the stator. pulse motor.