JPH08322236A - Cylindrical linear pulse motor - Google Patents

Abstract

PURPOSE: To make the thrust of a cylindrical linear pulse motor using a linear bearing, etc., uniform in each phase by preventing the dropping of the thrust. CONSTITUTION: A cylindrical linear pulse motor is composed of a cylindrical stator 1 in which salient poles arranged on the inner peripheral surface are respectively wound with windings and a mover 23 which is supported by bearings 19 and 20 in a state where the mover 23 can freely move in the axial direction in the stator 1 and in which small mover teeth 26 are arranged at regular pitches on the outer peripheral surface along the axial direction and the number of the salient poles of the stator 1 is set at M>=N (where, N is the number of rows of roll balls of the bearings 19 and 20 rolling in the axial directions). In addition, a plurality of recessed grooves 24 are formed corresponding to the bearings 19 and 20 on the outer peripheral surface of the mover 23 along the axial direction at the position corresponding to an opening between the salient poles of the stator 1 and raceway track members 25 which are used for rolling the balls of the bearings 19 and 20 and composed of a wear- resistant material are put in the grooves 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical linear pulse motor.

[0002]

2. Description of the Related Art FIG. 7 is a vertical sectional view of a conventional well-known cylindrical linear pulse motor, which is composed of a stator 100 and a mover 101. Stator 1
00 is a stator core 103, 104,
105 and 106 are arranged and the stator cores 103 and 10 are arranged.
Ring-shaped winding lines 108 and 109 are arranged in the recessed grooves 107 formed between the four and between the stator cores 105 and 106. The stator cores 103 and 104 are ring-shaped windings 1.
08 forms one phase with the stator core 10
5, 106 and the ring winding 109 form another phase.

On the inner peripheral surfaces of the stator cores 103, 104, 105 and 106, a plurality of stator small teeth 110 are arranged at an equal pitch in the axial direction. Then, the stator cores 103 and 104 and the stator core 10 that form two phases
Reference numerals 5 and 106 each have a ring-shaped permanent magnet 111 magnetized in the axial direction between them and constitute a two-phase stator 100 as a whole.

The mover 101 includes a mover core 112 and a shaft 1.
13, a plurality of mover small teeth 114 are arranged on the outer peripheral surface of the mover core 112 at the same pitch as the stator small teeth 110 and at an equal pitch in the axial direction.

The mover 101 is supported by brackets 115 and 116 provided at both ends of the frame 102 via bearings 117 and 118.

The bearings 117 and 118 are generally called slide bushes, linear bushes, linear bearings, etc., and are composed of a cylindrical outer cylinder, a plurality of rolling spheres, and a holder.

The plurality of rolling spheres are located between the outer cylinder and the outer peripheral surface of the shaft 113, and support the shaft 113 while directly rolling the outer peripheral surface in the axial direction. The holder holds the plurality of rolling spheres together with the outer cylinder, and aligns the rolling spheres in the axial direction,
A plurality of circulation grooves, which are a guide groove for rolling the outer peripheral surface of the shaft 113 and a return groove for returning the spherical body to circulate, are arranged on the inner peripheral surface at equal pitches. There is.

The stator small teeth 110 and the mover small teeth 114
And have the following positional relationship. That is, the stator core 1
The stator small teeth 110 arranged in
Just facing each other, the stator small teeth 110 arranged on the stator core 105 are at positions axially displaced from the stator core 106 by 2/4 of the tooth pitch.
In addition, the stator small teeth 110 arranged on the stator core 104.
Is at a position axially displaced from the stator core 106 by 1/4 of the tooth pitch. Further, the stator core 10
The stator small teeth 110 arranged on the stator core 106
Compared with, the position is shifted by 3/4 of the tooth pitch in the axial direction.

Then, by energizing the ring-shaped windings 108 and 109 in a predetermined order in accordance with the input pulse, magnetic flux is sequentially generated between each stator small tooth 110 and each movable small tooth 114. In this cylindrical linear pulse motor, the basic moving amount is a two-phase hybrid linear pulse whose basic moving amount is ¼ of the tooth pitch of the moving teeth 114. It constitutes a motor.

FIG. 8 shows a cross-sectional view of another conventional five-phase cylindrical linear pulse motor 200, which is composed of a stator 201 and a mover 202, and which is formed on the inner peripheral surface of the bracket at both ends of the stator 201. Bearing not shown (linear bearing) 2
03 is provided. The bearing 203 has a plurality of rolling spheres supported in guide grooves provided in the axial direction at three locations at equal intervals in the circumferential direction. On the outer peripheral surface of the moving element 202, three concave grooves 204 are provided in the axial direction at equal intervals in the circumferential direction.
Track members 205 made of wear-resistant material are fitted to the respective parts 04. Then, the plurality of rolling spheres roll along the track member 205. (Japanese Patent Application No. 5-310133) W201 to W205 are stator windings wound around each salient pole.

[0011]

However, in the above-mentioned conventional cylindrical linear pulse motor, the track member for rolling the rolling sphere of the bearing (linear bearing) fitted to the outer peripheral surface of the moving element is provided. Since it is arranged at a position facing the stator salient poles, there are problems that the motor thrust is reduced and the thrust for each phase becomes uneven.

The present invention has been made in view of the above points,
The purpose is to eliminate the above-mentioned problems, and a track member, which is fitted on the outer peripheral surface of the moving element and rolls a rolling sphere of a bearing (linear bearing), is located at a position facing the opening between the stator salient poles. An object is to provide a cylindrical linear pulse motor that is arranged.

Another object of the present invention is to provide a cylindrical linear pulse motor in which the number of stator iron plates forming the stator core of the stator is an integral multiple of the number of phases.

[0014]

The structure of the present invention for achieving the above object is such that a winding line is wound around each of a plurality of salient poles arranged along the inner peripheral surface, and the salient poles are wound around the salient poles. A cylindrical stator having a plurality of stator small teeth arranged along the axial direction at the ends of the poles, and concentrically with the axial center of the stator, and supported by a bearing so as to be movable in the axial direction. , A cylindrical linear pulse motor comprising a plurality of mover small teeth arranged at equal pitches on the outer peripheral surface in the axial direction,
It is as follows.

(1) When the number of rows of rolling spheres in the axial direction of the bearing is N and the number of stator salient poles is M, the number of stator salient poles is set so that M ≧ N. A plurality of recessed grooves are formed along the axial direction at positions corresponding to the openings between the stator salient poles on the outer peripheral surface of the mover, corresponding to the rows of rolling spheres of the bearing. A raceway member made of a wear-resistant material for rolling the rolling sphere of the bearing is fitted into these concave grooves.

(2) In (1), the stator is
A pair of stator cores arranged in the axial direction, permanent magnets arranged between the pair of stators and magnetized in the axial direction, and the salient poles arranged in the axial direction of the stator core. It is characterized in that it is composed of a stator winding wound around each other.

(3) In (1) or (2), in each of the pair of stator cores forming the stator, the stator iron plate forming the stator core has a predetermined angle in the circumferential direction. Each of the stator cores is formed by sequentially laminating and laminating, and each of the stator cores is formed by jL stator iron plates, where L is the number of phases and j is a positive integer.

[0018]

In the cylindrical linear pulse motor configured as described above, the rolling sphere of the bearing that movably supports the moving element in the axial direction is provided at the opening between the stator salient poles on the outer peripheral surface of the moving element. The moving member is moved along the track member that also functions as a guide and is fitted at a position corresponding to the position, while preventing the rotation of the moving element. Therefore, the thrust force for each phase is uniform, the leakage of magnetic flux from the small teeth of the stator is reduced, and the motor as a whole is small in size, high in efficiency, high in thrust, and long in stroke. Further, the stator core of the stator is formed by sequentially laminating a stator iron plate at every salient pole pitch angle or at every predetermined angle, and each of the stator cores has L as the number of phases, When j is a positive integer, it is formed of jL stator iron plates, so that the tip areas of the small teeth are the same for each phase, and the thrust is made uniform for each phase.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be exemplarily described in detail below with reference to the drawings. FIG. 1 is a vertical sectional view showing an embodiment of a cylindrical linear pulse motor of the present invention, and FIG.
1 is a transverse sectional view taken along line II-II of FIG. 1, and FIG. 3 is an explanatory sectional view of a bearing portion of FIG. In this embodiment, the numerical value of the number N of rows of rolling spheres in the axial direction of the bearing (herein, the bearing means, for example, a linear bearing or a ball spline) is N.
= 5, and the number M of stator salient poles is M = N = 5. (However, the number N of rows of rolling balls is N ≧ 2)

In FIGS. 1 to 3, reference numeral 1 denotes a stator housed in a cylindrical case 2, and the stator 1 is a pair arranged in parallel in the axial direction, each having the five salient poles. Between the stator cores 3 and 4, the permanent magnets 5 arranged between the stator cores 3 and 4 and axially magnetized and arranged in a ring shape or in a divided manner, and between the stator cores 3 and 4. It is composed of five stator windings W1 to W5 provided in the.

The stator cores 3, (4) each have five salient poles 6 to 1 projecting toward the center on the inner peripheral surface.
0 (salient poles 11 to 15) are provided at predetermined intervals along the circumferential direction, and a plurality of stators are axially provided on the inner peripheral surfaces of these salient poles 6 to 10 (salient poles 11 to 15). Small tooth 1
6 (tooth tips 16a and tooth bottoms 16b) are provided at equal pitches.

The stator winding W1 includes stator cores 3 and 4
It is wound over two salient poles 6 and 11 that overlap each other. Similarly, the stator windings W2, W3 to W
5 also has two salient poles 7 and 12, 8 and 13, 9 and 14, and 10 and 15 where the stator cores 3 and 4 overlap, respectively.
, Each of which is wound.

The permanent magnet 5 is sandwiched between the stator cores 3 and 4 and is magnetized in the axial direction.
As for the axial thickness of the stator core, the distance between the centers of the respective stator small teeth 16 arranged on the two stator cores 3 and 4 is (K + 0.5) times the tooth pitch (K is a positive value). It should be an integer).

Brackets 17, on both sides of the case 2,
18 is provided, and bearings (linear bearings) 19 and 20 of the same shape are fitted into the inner surfaces of the brackets 17 and 18.
Is provided. The bearings 19 and 20 are usually called linear bearings, linear bushes, slide bushes, ball splines and the like.

These bearings 19 and 20 are provided with ball guides 21 in the axial direction at five locations on the inner peripheral surface in the circumferential direction, and a plurality of balls (rolling spheres) are provided in the ball guides 21.
22 is supported. The ball guide 21 is composed of an annular guide groove consisting of a forward path and a backward path, and these balls (rolling spheres) 22 are fitted in a groove 24 provided in a moving element 23 described later to form a guide. It moves while rolling along the combined track member 25.

The track member 25 is provided on the outer peripheral surface of the moving element 23 at a position corresponding to the opening between the stator salient poles 6 to 10 or the salient poles 11 to 15 and the bearings 19, 2 are provided.
0 corresponding to each ball guide 21 (the bearing 1
(The same number as the number of threads N of 9, 20), five recessed grooves 24 are formed along the axial direction, and these recessed grooves 24 are fitted. The raceway member 25 is formed of a material having higher wear resistance than the mover 23 in order to guide and roll the rolling spheres 22 of the bearings 19 and 20.

As described above, since the track member 25 is fitted to the outer peripheral surface of the moving member 23 at a position corresponding to the opening between the stator salient poles 6 to 10 or the salient poles 11 to 15, The leakage of magnetic flux from the small stator teeth 16 is reduced, and the motor as a whole is small and highly efficient.

The mover 23 is formed integrally with the mover core in a hollow shape, and also serves as a mover shaft. In the axial direction of the outer peripheral surface of the moving element 23, a plurality of ring-shaped moving element small teeth 26 having the same tooth pitch as the stator small teeth 16 and an equal pitch are formed by forging, cutting or grinding. It is formed by machining.

FIG. 4 shows an example of the stator iron plate 27 forming the stator cores 3 and 4. The number of stator iron plates 27 constituting each of the stator cores 3 and 4 is formed by jL stator iron plates, where L is the number of phases and j is a positive integer. This stator iron plate 27 has five salient poles P.
Of 1 to P5, P1 and P2 are salient poles having a small inner diameter, and form the tooth tips 16a of the stator small teeth 16. Further, P3, P4, and P5 are salient poles having a large inner diameter and form the tooth bottom portion 16b of the stator small tooth 16.

FIG. 5 shows the stator iron plate 27 with a predetermined angle θ.
The state of the salient poles 6 to 10 of the stator cores 3 and 4 and the stator small teeth 16 of the salient poles 11 to 15 which are formed when the rotor cores 3 and 4 are laminated while being sequentially rotated by 72 degrees are seen from the moving element 23 side. It is a thing. The hatched part is the tip part 1
6a, and the portion without hatching shows the tooth bottom portion 16b.

The thickness of the stator iron plate 27 is t₀Then, times
By stacking layers, each salient pole 6 to 10 and salient pole
11 to 15 has a tooth pitch of L · t₀, Ie 5
・ T ₀, Tooth thickness is 2t₀The stator small teeth 16 are formed
It Moreover, when the salient poles 6 and 11 are used as a reference, the salient pole 7,
The deviation of the 12 small teeth 16 is 1 / L of the tooth pitch, that is, 1
/ 5, the deviation of the small teeth 16 of the salient poles 8 and 13 is 2 / of the tooth pitch.
L, that is, 2/5, the deviation of the small teeth 16 of the salient poles 9 and 14 is
3 / L of tooth pitch, that is, 3/5 of salient poles 10 and 15
The deviation of the small teeth 16 is 4 / L of the tooth pitch, that is, 4/5
is there.

On the other hand, the positional relationship between the stator small teeth 16 of each salient pole where the stator cores 3 and 4 overlap each other is adjusted by adjusting the axial thickness of the permanent magnet 5 as described above. Is set so as to deviate by 1/2 of the tooth pitch.

The phase in which the winding line W1 is wound is the A phase,
The phase in which the winding line W2 is rolled is the B phase, the phase in which the rolling line W3 is rolled is the C phase, the phase in which the rolling line W4 is rolled is the D phase, and the phase in which the rolling line W5 is rolled is E. By connecting so that they are in phase,
A 5-phase hybrid linear pulse motor can be constructed. The basic movement amount for each step at this time is
1 / (2 · L) of tooth pitch, that is, (5 · t ₀ ) / 1
It becomes ₀ and becomes 1/2 of the thickness t ₀ of the stator iron plate 27.

Then, by sequentially exciting each phase winding in a predetermined order in accordance with the input pulse, magnetic flux is sequentially generated between each stator small tooth 16 and each movable small tooth 26. The mover 23 can be stepped in steps. In this way, the number of stator iron plates 27 constituting each of the stator cores 3 and 4 is made an integral multiple of the number of phases L, so that the number of stator small teeth 16 of each phase becomes the same, and The thrust of can be made uniform.

FIG. 6 is a transverse sectional view corresponding to FIG. 2 showing another example of the cylindrical linear pulse motor of the present invention. Each positive integer j and the number of phases L are j = 2, L. = 5, the number of stator salient poles M is M = jL
= 10. Ten stator windings W1 to W10 are wound around the ten salient poles 31 to 40 arranged on each stator core of the stator. The track member 25 includes the stator salient poles 31 and 32, 33 and 34, 35 and 36, 37 and 3 on the outer peripheral surface of the mover 23.
8, 5 and 5 along the axial direction at positions corresponding to the openings between 39 and 40, corresponding to the ball guides 21 of the bearings 19 and 20 (the same number as the number of threads N of the bearings 19 and 20). Individual concave grooves 24 are formed and fitted into these concave grooves 24. The operation is similar to that of the cylindrical linear pulse motor of the above embodiment.

Note that the technique of the present invention is not limited to the technique in the above-described embodiment, and may be implemented by means of another aspect having the same function, and the technique of the present invention can be variously modified within the scope of the above configuration. Can be changed or added.

[0037]

As is apparent from the above description, according to the cylindrical linear pulse motor of the present invention, in claims 1 and 2, the number of rows of rolling spheres in the axial direction of the bearing is fixed to N. When the number of the salient salient poles is M, it is set such that M ≧ N, and at the position corresponding to the opening between the stator salient poles on the outer peripheral surface of the mover, the rolling sphere of the bearing is Since a plurality of concave grooves are formed along the axial direction corresponding to the rows, and a race member made of a wear-resistant material for rolling the rolling elements of the bearing is fitted in these concave grooves, Is small and generates high thrust, and the thrust for each phase is uniform.

According to the third aspect of the present invention, in each of the pair of stator cores forming the stator, the stator iron plate forming the stator core is circumferentially arranged at every pitch angle of salient poles or at a predetermined angle. Each of the stator cores is formed by jL stator iron plates, where L is the number of phases and j is a positive integer. Generates high thrust and makes thrust uniform for each phase. Furthermore, since the stator core can be formed by sequentially rotating and laminating the stator iron plates by a predetermined angle (spacing angle of salient poles), the conventional laminated core technology of the rotary stepping motor can be applied and the productivity is excellent. There is.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a cylindrical linear pulse motor of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG.

FIG. 3 is an explanatory sectional view of a bearing portion of FIG.

FIG. 4 is a plan view of a stator iron plate forming a stator core.

5 is a development view of a stator small tooth portion formed when the stator iron plates of FIG. 4 are rotationally stacked at a predetermined angle, as viewed from the mover side.

FIG. 6 is a transverse sectional view corresponding to FIG. 2 showing another example of the cylindrical linear pulse motor of the present invention.

FIG. 7 is a vertical cross-sectional view of a conventional cylindrical linear pulse motor.

FIG. 8 is a cross-sectional view of another conventional 5-phase cylindrical linear pulse motor.

[Explanation of symbols]

1 Stator 3,4 Stator core 5 Permanent magnet 6,7, ... 10,11,12, ... 15,31,3
2, ... 40 Salient pole 16 Stator small tooth 19,20 Bearing 22 Rolling sphere 23 Moving element 24 Recessed groove 25 Raceway member 26 Moving element small tooth 27 Stator iron plate k, j Integer N Rolling of bearing in axial direction Number of rows of spheres L Number of phases P1, P2, ... P5 Salient poles W1, W2, ... W10 Stator winding line t ₀ Stator iron plate thickness

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hirofumi Satomi 1400 Shinogoroda, Kashiwa-shi, Chiba Oriental Motor Co., Ltd. (72) Inventor Tadashi Okada 1400 Shinogoroda, Kashiwa-shi, Chiba Oriental Motor Co., Ltd.

Claims (3)

[Claims] 1. A winding wire is wound around each of a plurality of salient poles arranged along the inner peripheral surface, and a plurality of stator small teeth are axially provided at the tips of the salient poles. A cylindrical stator provided and a plurality of mover small teeth which are supported concentrically with the axial center of the stator by a bearing so as to be movable in the axial direction and along the outer peripheral surface along the axial direction. In a cylindrical linear pulse motor consisting of moving elements arranged at equal pitches, where N is the number of rows of rolling spheres of the bearing in the axial direction and M is the number of salient poles of the stator, the fixed The number of salient salient poles is set to M ≧ N, and the outer peripheral surface of the mover corresponds to the row of rolling spheres of the bearing at a position corresponding to the opening between the stator salient poles. To form a plurality of grooves along the axial direction, and a track made of wear-resistant material for rolling the rolling spheres of the bearing in these grooves. Cylindrical linear pulse motor, characterized in that for fitting the member. 2. The stator comprises a pair of stator cores arranged in the axial direction, permanent magnets arranged between the pair of stators and magnetized in the axial direction, and the stator. The cylindrical linear pulse motor according to claim 1, wherein the cylindrical linear pulse motor comprises a stator winding wire wound between the salient poles arranged in the axial direction of the child core. 3. A pair of stator cores forming the stator has a stator iron plate forming the stator core,
The stator cores are formed by sequentially laminating at predetermined angles in the circumferential direction, and each of the stator cores is formed by jL stator iron plates, where L is the number of phases and j is a positive integer. The cylindrical linear pulse motor according to claim 1 or 2, characterized in that.