JPH02280655A - Pulse motor - Google Patents

Abstract

PURPOSE:To shorten magnetic path and to reduce flux leakage by providing permanent magnets magnetized in parallel with a secondary scale and buried in the end faces of respective magnetic poles at the primary flux generating section facing with the secondary scale then providing a plurality of pole teeth in the opposite end faces of the permanent magnets. CONSTITUTION:When current is fed to phase A and B coils 24A, 24B, magnetomotive force is produced in a core 23 from phase B pole 23PB toward phase A pole 23PA and a main flux loop is formed as shown by phi5. Consequently, the position where the pole teeth 27a of phase A split pole 23A faces with the teeth section 21a of scale 21 and the pole teeth 29a of phase B split pole faces with the teeth section 21a of the scale 21 is stabilized magnetically. When current is fed to phase C and D coils 24C, 24D, a main flux loop phi10 is produced, and the position where the teeth section 32a of phase C split pole 23C' faces with the teeth section 21a of the scale and the teeth section 34a of phase D split pole 23D' faces with the teeth section 21a of the scale 21 is stabilized magnetically.

Description

DETAILED DESCRIPTION OF THE INVENTION ``Industrial Application Field'' This invention relates to a pulse motor applied to the head feeding of a printer, the head feeding of a photoelectric reader, etc. ``Prior Art'' As is well known, linear The pulse motor drives the slider or the secondary slider based on the pulse signal supplied to the primary slider.
The scale on the next side is moved in a stepwise manner, and the configuration of its magnetic circuit is as shown in FIG.

In this figure, l is a scale made of a long plate-like magnetic material, and the top surface of the scale has uneven teeth 1.
a, 1 a, . . . are formed at equal intervals along the longitudinal direction (horizontal direction in the drawing). A slider 2 is placed on the upper surface of the scale 1 so as to be movable in the longitudinal direction of the scale 1 by a support mechanism including rollers (not shown). The slider 2 has a U-shaped A-phase iron core 4.
and coils 6a and 6b wound around the B-phase iron core 5 and the A-phase magnetic pole 4a and the Al-phase magnetic pole 4b of the A-phase iron core 4, respectively.
, coils 7a and 7b respectively wound around the B-phase magnetic pole 5a and B1-phase magnetic pole 5b of the B-phase iron core 5, permanent magnets 8 and 9 attached to the upper surfaces of the iron cores 4 and 5 with the polarities shown in the figure, It is comprised of a back plate 10 made of a plate-shaped magnetic material attached to the upper surface of magnets 8 and 9. On the lower surface of the magnetic pole 4a, there are pole teeth 14 having the same pitch as the pitch P of the teeth 1a of the scale l.
Three magnetic poles 4b and 5a are formed.

Similarly, there are pole teeth I 4b I 5a, 15 on each lower surface of 5b.
b are formed respectively. In addition, these pole teeth 14b, 1
5a and 15h are arranged sequentially shifted by P/4 with respect to the pole tooth 14a, and the pole teeth! 4a, l 4b, 15a
.

A predetermined gap G is formed between each lower surface of the tooth portion 15b and the upper surface of the tooth portion 1a. And coil 6a
, 6b, 7a, 7b by sequentially supplying predetermined pulse signals to the coils 6a, 6b,
The magnetic flux generated by 7a and 7b and the magnetic flux generated by the permanent magnet 8.9 are sequentially applied to each magnetic pole 4a, 4b, 5a, and 5b, and the magnetically stable position of the slider 2 with respect to the scale l is sequentially adjusted. This causes the slider 2 to move along the longitudinal direction of the scale l.

Here, two sets of coils 6 a, 6 b and 7 a 7
In b, an example will be described in which the slider 2 is driven by a two-phase excitation method that constantly supplies current.

■As shown in Figure 7 (a), coils 6a and 6b
A predetermined current is passed from terminal 6c to 6d, and
By passing a predetermined current through the coils 7a and 7b from the terminals 7d to 7C, the magnetic flux generated by the coil 6a and the magnetic flux generated by the permanent magnet 8 are added to each other at the A-phase magnetic pole 4a, forming an Al-phase magnetic pole. 4b, the magnetic flux generated by the coil 7a and the magnetic flux generated by the permanent magnet 9 are added to each other at the B-phase magnetic pole 5a, and Bl
Since they cancel each other out in the phase magnetic pole 5b, a main magnetic flux shown by the solid line φ1 in the figure is generated, and as a result, the A-phase magnetic pole 4a
A magnetically stable position is a position where each of the pole teeth 14a and 15a of the B-phase magnetic pole 5a and the tooth portion 1a of the scale I are vertically opposed to each other.

■As shown in Figure 7 (b), a predetermined current is passed through the coils 6a and 6b in the same direction as ■, and the coils 7a,
7 By passing a specified current through b in the opposite direction to ■,
The main magnetic flux shown by the solid line φ is generated in the figure, and as a result, the convex pole 1
The position where the teeth 14a and 15b and the tooth portion 1a vertically face each other is a magnetically stable position.

■As shown in Figure 7 (c), by passing a predetermined current through the coils 6a and 6b in the opposite direction to ■, the solid line φ,
A main magnetic flux shown by is generated, and as a result, the position where each of the pole teeth 14b and 15b and the tooth portion 1a are vertically opposed becomes a magnetically stable position.

■As shown in Figure 7 (c), coils 6a and 6b
While passing a predetermined current in the same direction as ■, the coils 7a,
By passing a predetermined current through 7b in the opposite direction to ■, a main magnetic flux is generated as shown by the solid line φ4 in the figure, and as a result, the convex pole ml
The position where 4b and 15a and the tooth portion 1a are vertically opposed is a magnetically stable position.

By repeating the pulse excitation in the order of the above excitation modes (■-■-■-■), the slider 2 moves in the right direction in the drawing, that is, in the direction from the magnetic poles 4a to 5b. Further, by repeating pulse excitation in the order of excitation modes ■-〇-■-■, the slider 2 moves to the left in the drawing, that is, in the direction from the magnetic pole 5b to the magnetic pole 4a. The same applies to the case where the slider 2 is fixed and the scale I is moved.

"Problems to be Solved by the Invention" By the way, the above-mentioned linear pulse smoke has the following problems.

■ Mechanical strength is low because the A-phase core 4 and B-phase core 5 are separated.

- Since the permanent magnets 8 and 9 are far from the gap G, leakage magnetic flux increases, and the permanent magnets must be made larger accordingly. Furthermore, when the permanent magnet is made large, the detent force becomes large, making it difficult to move it by hand when no current is applied.

- Since the length of the magnetic path varies depending on the excitation mode (see Figure 7 (a) to (d)), the thrust is not constant.

This invention was made in view of the above-mentioned circumstances, and aims to provide a pulse motor that can shorten the magnetic path, reduce leakage magnetic flux, and obtain sufficient mechanical strength. There is.

"Means for Solving the Problem" The present invention includes a secondary scale in which teeth are formed at equal intervals P in a specific direction, and a secondary scale that is movable in the specific direction with respect to the secondary scale. a supported primary magnetic flux generating section, each gap formed between each @ pole around which a coil of the primary magnetic flux generating section is wound and each tooth section of the secondary side scale; In a pulse motor that moves the primary side magnetic flux generating section relative to the secondary side scale by sequentially generating magnetic flux, each magnetic pole of the primary side magnetic flux generating section facing the secondary side scale is A permanent magnet is embedded in the end face and magnetized in a direction parallel to the secondary scale, and a plurality of pole teeth are formed on both end faces of the permanent magnet, and one of the end faces of the permanent magnet is provided with a plurality of pole teeth formed on both end faces of the permanent magnet. A pole tooth and the other pole tooth are in a positional relationship shifted by P/2, and the pole tooth of each magnetic pole adjacent to the permanent magnet is (
1/magnetic pole) XP.

"Operation, 1. According to this invention, since the permanent magnet is arranged near the gap between the primary side magnetic flux generating part and the secondary side scale, when current is passed through the coil, the primary side magnetic flux generating part Magnetic flux flows from the pole tooth of the magnetic pole to the adjacent north pole tooth through the permanent magnet of the magnetic pole, and the magnetic flux that flows from the pole tooth to the teeth of the secondary scale becomes the primary magnetic flux. A main magnetic flux loop is formed that flows into the S pole tooth of the other magnetic pole in the generating part, flows into the adjacent N pole tooth through the permanent magnet of that magnetic pole, and then returns to the original magnetic pole. Therefore, leakage magnetic flux can be reduced and the length of the magnetic path can be made constant.

"Embodiment" Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a magnetic circuit of a linear pulse motor according to a first embodiment of the present invention.

In this figure, 21 is a fixed scale, and tooth parts 21a, 21a, . . . are formed on the upper surface of the scale 21 at intervals of a pitch P along its longitudinal direction.

On the other hand, 22 is a slider (primary side magnetic flux generating section), which is supported by a not-shown support mechanism such as a roller so as to be movable along the longitudinal direction of the scale 21 (in the direction of arrow M shown in the figure).

The slider 22 has magnetic poles, .
3PA, an iron core 23 having a B-phase magnetic pole 23PI3, a C-phase magnetic pole 23PC, a D-phase magnetic pole 23PD, and each @pole 23PA to 2.
Horizontal stripes are formed from coils 24A to 24D wound around the 3PD. In addition, at the lower ends of grtt poles 23PA to 23PD, there are two divisions @poles 23Δ, 238 to 23PD, respectively.
23D and 23n are formed, and further, a groove is formed between the two divided magnetic poles, and permanent magnets 25A to 25D are inserted into these grooves 11, respectively. These permanent magnets 25A to 25D are connected to adjacent magnetic poles 2 as shown in the figure.
5A to 25D are magnetized to have opposite polarity.

Furthermore, three pole teeth 27a having the same pitch as the pitch P of the teeth 121a of the scale 21 are formed on the lower surface of the A-phase divided magnetic pole 23A, and the other divided magnetic poles 23, 23 B, 23
Pole teeth 28a, 29a, 30a, 31a, 32a,
33a and 34a are formed respectively.

These pole teeth 27a to 34a have a positional relationship in which the pole teeth on both sides sandwiching each permanent magnet are shifted by P/2. For example, as shown in the figure, the pole teeth 27a of the A-phase divided magnetic pole 23A or the scale 2
The in-phase split magnetic pole 2 faces the tooth portion 21a of 1.
The pole tooth 28a to the third magnetic pole is shifted by P/2 from the tooth portion 21a, and similarly, the pole teeth of the other divided magnetic poles are also shifted by P/2 from each other.

In addition, the positional relationship of the pole teeth of the divided magnetic poles of each magnetic pole 23PA to 23PD is based on the pole tooth 27a of the A-phase divided magnetic pole 23A.
0 degrees), the pole teeth 30a of the 0-phase divided magnetic pole 23fl are located 180 degrees apart, and the pole teeth 31 of the C-phase divided magnetic pole 23G are located 180 degrees apart.
a are located 90 degrees apart, and the pole teeth 34a of the D-phase divided magnetic poles 23rl are located 270 degrees apart. Thereby, the divided magnetic pole 23A.

23 C, 23I3, 2.3 D order IC, S) r-Rule 21+7) The phase relationship with respect to each tooth portion 21a is displaced by P/4 in the direction of movement (direction of arrow M). .

In addition, the pole teeth 29a of the B-phase divided magnetic pole 23B are in phase (0 degree) with the pole teeth 27a of the A-phase divided magnetic pole 23A, and based on the pole tooth 29a of the B-phase divided magnetic pole 23B, the in-phase divided magnetic pole 23 The pole teeth 28a of the C phase division @ pole 231m are located 270 degrees apart, and the pole teeth 32a of the C phase division @ pole 231m are located 270 degrees apart,
The pole teeth 33a of the phase-divided magnetic pole 23D are located 90 degrees apart. As a result, the divided magnetic poles 23B, 23D, 23 people,
23C, the phase relationship of the scale 21 to each tooth 21a is displaced by P/4 in the direction of movement (direction of arrow M).

Next, we will discuss the operation of the above-mentioned linear pulse motor in a second manner.
This will be explained with reference to the figures.

■ In the state shown in FIG. 2 (A), when currents are passed through the A-phase and B-phase coils 24A and 24B in the directions shown in the figure, the iron core 23 has a magnetic flux from the B-phase magnetic pole 23PB to the A-phase magnetic pole 23PA.
A magnetomotive force is generated by the coils 24A and 24B toward
This forms a main magnetic flux loop indicated by φ5 in the figure.

As a result, the position where the pole tooth 27a of the A-phase divided magnetic pole 23A faces the tooth portion 21a of the second scale, and the pole tooth 29a of the B-phase divided magnetic pole 23B or the tooth portion 21a of the scale 21 is magnetically stabilized. position.

In addition, in the C-phase magnetic pole 23PC and the D-phase magnetic pole 23PD, since the coils 24C and 24D of both magnetic poles are not energized, as shown in the figure, electricity is generated from the N pole of the permanent magnet 25C of the C-phase magnetic pole 23PC. The magnetic flux is the C phase magnetic pole 2aPC
passes through the inside, enters the S pole of permanent magnet 25C, and enters the magnetic flux loop φ6
In addition, the magnetic flux generated from the N pole slightly flows from the pole tooth 31a of the C-phase divided magnetic pole 23C to the pole tooth 21a of the scale 21, passes through the scale 21, and flows from the pole tooth 21a to the C-phase divided magnetic pole. It flows into the pole tooth 32a of ff1231m and enters the S pole, forming a magnetic flux loop φ7 (indicated by a broken line).

Furthermore, the permanent magnet 25D of the D-phase magnetic pole 23PD generates a magnetic flux loop φ8 in the opposite direction to the magnetic flux loop φ6, and a magnetic flux loop φ9 in the opposite direction to the magnetic flux loop φ7. However, those magnetic flux loops φ7. Since the magnetic flux of φ9 is much weaker than the magnetic flux of the main magnetic flux loop φ5,
There is no need to move the slider 22.

■As shown in Figure 2 (b), the C phase and D phase coils 24
When a predetermined current is applied to G and 24D in the direction shown in the figure, a main magnetic flux loop shown as φlO in the figure is generated, and as a result, the pole teeth 32a of the phase-divided magnetic pole 23C are connected to the teeth of the scale 21. 21a, the pole tooth 34a of the D-phase divided magnetic pole 23b
The position facing the tooth portion 21a of the scale 21 is a magnetically stable position.

In addition, magnetic flux loop φ11, magnetic flux loop φ12, magnetic flux loop φ13, and magnetic flux loop φ14 are generated in the magnetic poles 23PA and 23PH in the non-energized state by the permanent magnets 25A and 25B.

■As shown in Figure 2 (c), the A-phase and B-phase coils 24
When a predetermined current is passed through A and 24B in the opposite direction to ■, a main magnetic flux loop shown as φ15 in the figure is generated, and as a result, the pole teeth 28a to the human phase dividing magnetic pole 23 are connected to the teeth 21a of the scale 21.
The position where the pole tlJ 30a of the 0-phase divided magnetic pole 23n faces the tooth portion 21a of the scale 21 is a magnetically stable position. In addition, the magnetic pole 23PC in the non-energized state,
23PD includes a magnetic flux loop φ16 and a magnetic flux loop φ17, and a magnetic flux loop φ18 and a magnetic flux loop φ1, respectively.
9 occurs.

■As shown in Figure 2 (d), the C phase and D phase coils 24
When a predetermined current is passed through C and 24B in the opposite direction to ■, φ is shown in the figure.
A main magnetic flux loop indicated by 20 is generated, and as a result, the pole tooth 31a of the C-phase divided magnetic pole 23C faces the tooth portion 21a of the scale 2I, and the pole tooth 33a of the D-phase divided magnetic pole 23D faces the scale 2I.
The position facing the first tooth portion 21a is a magnetically stable position. In addition, the magnetic poles 23 PA, 23 P in the non-energized state
H has a magnetic flux loop φ21 and a magnetic flux loop φ, respectively.
22, a magnetic flux loop φ23, and a magnetic flux loop φ24 are generated.

By repeating the pulse excitation in the order of the above excitation modes ■-■-■-■, the slider 22 moves to the right in the drawing by PI3, and the pulse excitation is performed in the order of the excitation modes ■-■-■-■. By repeating this, the slider 22 moves to the left in the drawing by PI3.

Next, referring to FIG. 3, a linear pulse smoke according to a second embodiment of the present invention will be described.

In this figure, parts corresponding to those in FIG. 1 are given the same reference numerals, and their explanations will be omitted.

The linear pulse motor according to the second embodiment differs from the linear pulse motor according to the first embodiment in that the Nff1 and S poles of the permanent magnets 25B and 25D inserted in the iron core are magnetized in the opposite manner. Each magnetic pole 23PA~2
The difference is that the positional relationship of the pole teeth of the divided magnetic poles of the 3PD is different as shown below.

First, the pole tooth 27a of the A-phase divided magnetic pole 23A is used as a reference (0 degree).
Then, the pole teeth 29a of the B-phase divided magnetic pole 23B are located 180 degrees apart, and the pole teeth 33a of the D-phase divided magnetic pole 23D are 27 degrees apart.
They are located 0 degrees apart. As a result, the divided magnetic pole 23A
, 230.23B, and 23D, the phase relationship of the scale 21 with respect to each tooth portion 2La is displaced by PI3 in the direction of movement (direction of arrow M).

Further, the pole teeth 30a of the n-phase divided magnetic pole 230 are in phase (0 degree) with the pole teeth 27a of the A-phase divided magnetic pole 23A, and the in-phase divided magnetic pole 2
The pole teeth 28a of the C-phase divided magnetic poles 23C are located 270 degrees apart, and the pole teeth 34a of the D-phase divided magnetic poles 23b are located 90 degrees apart. As a result, the divided magnets i23 n, 23 I), 2 a
A, 2 s Q order 2, each tooth part 21a of the scale 21
The phase relationship for is in the direction of movement (direction of arrow M),
This means that it is displaced by PI3.

In such a configuration, when a current is passed through each coil as in the first embodiment, the excitation mode of
a and the teeth 21a of the scale 21 face each other, and ■
The C-phase and D-phase divided magnetic poles 23
The pole teeth 32a and 33a of C and 23D and the tooth portion 21a of the scale 21 face each other, and in the excitation mode of ■,
23 divided magnetic poles for input phase and B phase, 23B pole teeth 28a
, 29a and the tooth portion 21a of the scale 21 face each other, and in the excitation mode (2), the pole teeth 31a, 34a of the C-phase and B-phase divided magnetic poles 23C, 23D and the scale 2
When the first tooth portions 21a face each other, a magnetically stable position is achieved. Therefore, the ■−■−■
- By repeating pulse excitation in the order of each excitation mode, the slider 22S moves to the right in the drawing by PI3, and by repeating pulse excitation in the order of each excitation mode of ■-■-■-■, the slider 22S or move to the left of the drawing by P/・1.

Next, referring to FIG. 4, a three-phase linear pulse motor, which is a third embodiment of the present invention, will be described. In this figure, 41 is a scale, and tooth portions 41a are formed at regular intervals on the upper surface.

42 is a slider supported movably in the longitudinal direction of the scale 41 by a support mechanism such as a roller (not shown). The slider 42 includes an iron core 43 having an A-phase magnetic pole 43A, a B-phase magnetic pole 43B, and a C-phase magnetic pole 43C, and coils 44A to 44 wound around each of the magnetic poles 43A to 43C.
It is composed of C. At the center of the end face of each magnetic pole 43A, 43B, 43C facing the scale 41,
Concave grooves are formed, and permanent magnets 45A are installed in these grooves.
, 45B, and 45C are inserted, respectively. In addition, two pole teeth 46a, 46a and 47a47a are formed on both end faces of the A-phase magnetic pole 43A sandwiching the permanent magnet, and similarly, two pole teeth 46a, 47a and 47a are formed on the B-phase magnetic pole 43B.
8a, 49a, and 49a, and the C-phase magnetic pole 43C has pole teeth 50a, 50a, and 51a.

51a are formed respectively.

In addition, these pole teeth 46a to 51a have a positional relationship in which the pole teeth on both sides sandwiching each permanent magnet are shifted by PI2, and
The positional relationship of the pole teeth between each magnetic pole, or the pole tooth 4 of the A phase magnetic pole 43A.
6a as a reference (0 degree), the pole tooth 48 of the B-phase magnetic pole 43B
a is turned 120 degrees, and the pole tooth 50a of the C-phase magnetic pole 43C is turned 2
They have a positional relationship that changes by 40 degrees.

In such a configuration, the slider 4 is supplied with a pulse current whose polarity is reversed to the A-phase coil 44A, the B-phase coil 44B, and the C-phase coil 44C, respectively.
2 moves.

Next, with reference to FIG. 5, a description will be given of a three-phase rotary pulse motor according to a fourth embodiment, which is a rotational version of the three-phase linear pulse motor according to the third embodiment of the present invention.

In this figure, 60 is a rotor fixed to the shaft S. Teeth 60a are formed on the circumferential surface of the rotor 60 at a constant pitch P.

61 is a cylindrical stator. On the inner peripheral surface of this stator, six magnetic poles 61A, 61B, 61C, 61A are arranged at equal intervals.
, 61 El, 61 Qh<formed tLC O'), each of these magnetic poles 61A to 61C has a coil 64A.

64 B, 64 C, 64 A, 64 F3.64 fi
is wound. In addition, each group I facing the rotor 60
A groove is formed in the center of the end face of Mi61A to 61(m), and a permanent magnet 63A6 is installed in each of these grooves.
3 B, 63 C, 63 A, 63 [(,630,h<
I'm inserting it. In addition, pole teeth 65a to 76a are provided on both end surfaces of the permanent magnets 63A to 63C of each magnetic pole 61A to 61c.
are formed, and these pole teeth 65a to 76a have a positional relationship in which the pole teeth on both sides sandwiching a permanent magnet of the same magnetic pole are shifted by P/2, and the positional relationship of the pole teeth between each magnetic pole is But, A
With the pole teeth 65a of the phase magnetic pole 61A and the pole teeth 71a of the incoming phase magnetic pole 61A facing the teeth 60a of the rotor 60, the pole teeth 67a of the B-phase magnetic pole 61B and the 0-phase magnetic pole 611m
The pole tooth 73a of the C-phase magnetic pole 61C and the pole tooth 75a of the C-phase magnetic pole 61c are in a positional relationship in which the pole tooth 73a of the C-phase magnetic pole 61C is shifted by 240 degrees from the tooth portion 60a.

In such a configuration, the A phase and human phase coils 64
The rotor 60 is rotationally driven by supplying pulse currents having inverted polarities to the A and 64 coils, the B-phase and B-phase coils 64B and 64Q, and the C-phase and C-phase coils 64C and 164C, respectively.

Note that the present invention is not limited to the embodiments described above, and various modifications shown below are possible.

(2) A double-sided linear pulse motor may be used in which teeth are formed on the upper and lower surfaces of the secondary scale, and the primary slider is fixed to the upper and lower surfaces of the secondary scale using a support mechanism such as a roller. Further, as a modification of this double-sided linear pulse motor, a linear pulse motor may be constructed by fixing the primary slider to the upper and lower surfaces of the secondary scale.

(2) The primary slider may be provided with a sensor that detects relative movement with respect to the secondary scale, and may be driven as a servo motor.

■In order to eliminate cogging or improve thrust waveform distortion, a skew structure may be used, or a slight pitch shift within the same pole (equivalent skew) may be applied.

■For rotary pulse motors, an outer rotor structure, a structure in which the rotor is shaped like a disk, etc. are possible.

"Effects of the Invention" As explained above, according to the present invention, there is provided a secondary scale in which tooth portions are formed at equal intervals P along a specific direction, and a The primary wind flux generating section is movably supported, and is formed between each magnetic pole around which a coil of the primary wind flux generating section is wound and each tooth section of the secondary scale. In the pulse motor that moves the primary side air flux generation part relative to the secondary side scale by sequentially generating magnetic flux in each gap formed by the magnetic flux, the primary side air flux facing the secondary side scale is A permanent magnet is embedded in the end face of each magnetic pole of the generating part and magnetized in a direction parallel to the secondary scale, and a plurality of pole teeth are formed on both end faces of this permanent magnet. It has the effects described below.

■Since the iron core is integrally formed, rigidity and strength are increased.

■Since a permanent magnet is embedded in the end face of the iron core facing the gap, leakage magnetic flux is reduced and the necessary magnetic flux can be efficiently circulated. Therefore, a small permanent magnet can be used.

In addition, since the permanent magnet can be made smaller, most of the magnetic flux of the permanent magnet is short-circuited within the core when no current is applied, so the magnetic flux that circulates between the slider and the scale through the gap becomes small. This reduces the detent force and allows the slider to be moved easily by hand.

In addition, since the circulating magnetic flux of the permanent magnet does not flow through the yoke, the thickness of the yoke can be made thinner, which makes it possible to reduce the weight of the slider, which improves responsiveness when pulsed excitation is used. Ru.

■When each phase coil is excited, the length of the magnetic path becomes equal, so the thrust force variation between phases is reduced.

[Brief explanation of drawings]

Fig. 1 is a side view showing the structure of a linear pulse motor according to a first embodiment of the present invention, and Figs. 2 (a) to (d) are side views illustrating the operation of the linear pulse motor according to the same embodiment. , FIG. 3 is a side view showing the structure of a linear pulse motor according to a second embodiment of the invention, and FIG. 4 is a side view showing the structure of a three-phase linear pulse motor according to a third embodiment of the invention. 5 is a sectional view showing the structure of a three-phase rotary pulse motor according to a fourth embodiment of the present invention, and FIG. 6 is a side view showing the structure of a linear pulse motor according to a conventional embodiment.
FIGS. 7A to 7D are side views for explaining the operation of the linear pulse motor according to the same embodiment. 21...Slider (primary side magnetic flux generation part), 21
a...Tooth section, 22...Scale (secondary side scale), 23...Iron core, 23PA...
...Am magnetic pole, 23PB...B phase magnetic pole, 23P
C...C-phase magnetic pole, 23PD...D-phase magnetic pole, 23A...A-phase divided magnetic pole, 23B...
・B phase divided magnetic pole, 23C...C phase divided magnetic pole, 2
3D...D phase split magnetic pole, 24A...A
Phase coil, 24B...B phase coil, 24C...
...C phase coil, 24D...D phase coil,
25A-25D...Permanent magnet, 27a-34a
・・・・・・Polar teeth.

Claims (1)

[Scope of Claims] A secondary scale having teeth formed at equal intervals P along a specific direction, and a primary magnetic flux generator supported movably in the specific direction with respect to the secondary scale. by sequentially generating magnetic flux in each gap formed between each magnetic pole around which a coil of the primary side magnetic flux generating section is wound and each tooth section of the secondary side scale, In the pulse motor that moves the primary side magnetic flux generation section relative to the secondary side scale, the pulse motor is embedded in the end face of each magnetic pole of the primary side magnetic flux generation section facing the secondary side scale, and It has a permanent magnet magnetized in a direction parallel to the scale, and has a plurality of pole teeth formed on both end faces of the permanent magnet, and one pole tooth and the other pole tooth on both end faces of the permanent magnet are provided. The pole teeth of each magnetic pole adjacent to the permanent magnet are shifted by P/2, and the pole teeth are (
A pulse motor characterized by having a positional relationship shifted by 1/magnetic pole)×P.