JPH02246761A - linear motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a linear motor, and particularly to a linear motor that can reduce detent force.

[Conventional technology]

In order to reduce the motor's cogging torque (called detent force in linear motors), it is common to skew the magnetic pole teeth. The characteristics change depending on the accuracy of the angle when

Therefore, the technology related to the skew of conventional linear motors is
December 10, 1986, published by Kogyo Kenkyukai, page 192.
As shown in Photo 2(b), a method of skewing the slots or magnets is to arrange diamond-shaped permanent magnets on the mover.

[Problem to be solved by the invention]

However, in the prior art as described above, it is necessary to skew the magnetic poles of either the mover or the stator, which causes the following problems.

(1) When skewing the magnetic poles of permanent magnets, a combination of diamond-shaped permanent magnets is used, which takes time to process.

(2) When making a core by skewing a silicon steel plate,
Because the shifted angle is not in a straight line and becomes jagged,
Changes in permeance between magnetic pole teeth are not constant with respect to position, reducing the skew effect. Furthermore, when the core is skewed, there is a drawback that the number of steps is increased.

An object of the present invention is to provide a linear motor that solves the problems of the prior art described above.

[Means to solve the problem]

The above object is achieved by, when configuring a linear motor by combining a non-skewed mover magnetic pole unit and a non-skewed stator magnetic pole unit, by mounting the two units so that they face each other at the same angle as the relative skew. achieved.

[Effect]

Accordingly, when the present invention configures a linear motor by combining a non-skewed mover magnetic pole unit and a non-skewed stator magnetic pole unit, the two units are arranged so that they face each other at the same angle as the relative skew of the two units. By attaching it, a substantial skew effect can be obtained, and the man-hours such as processing a permanent magnet into a rhombus shape or shifting silicon steel plates can be omitted.

[Example] The present invention will be explained below based on an example of FIGS. 1 to 5, taking as an example a case where the present invention is applied to a two-phase linear motor. FIG. 2 is a perspective view of only the stator magnetic pole unit 2, FIG. 3 is a plan view of the mover magnetic pole unit 1, and FIG. 4 is a perspective view of the linear motor of the present invention. Plan view,
FIG. 5 is a sectional view taken along the line AA' in FIG. 4.

As shown in FIG. 1, in the mover magnetic pole unit 1, the N pole and S pole of the permanent magnet 11 are arranged alternately. However,
Since this embodiment is an example applied to a two-phase motor, at least two stator magnetic pole units 2 are required. They will be described below as stator magnetic pole units 2a and 2b, respectively.

That is, the phase of the stator magnetic pole teeth 21b provided in the stator magnetic pole unit 2b has a relationship of 360 degrees Xn±90 degrees (n is an integer) in electrical angle with respect to the stator magnetic pole teeth 21a.

Further, the stator magnetic pole unit 2 has stator magnetic pole teeth 21 provided at the tip of the stator yoke 22, and coils 23 are wound respectively, so that the movable magnetic pole unit 1 and the stator magnetic pole unit 2 are connected to each other. is stator magnetic pole unit 2
The mover magnetic pole unit 1 is arranged in the gap with a slight air gap.

In the above configuration, the detent force of the linear motor is
Although this occurs at the period of the magnetic pole tooth pitch, in this embodiment, in order to reduce the influence of the detent force, the mounting position of the stator magnetic pole unit 2 is changed to the movable magnetic pole unit 1.
They are arranged at a 1/4 pitch skew with respect to the direction of travel.

As shown in FIG. 2, the stator magnetic pole unit 2 has a structure that does not skew, and as shown in FIG. It is magnetized at right angles to the direction of movement of the child magnetic pole unit 1, and with the above configuration, it is possible to skew a generally known permanent magnet without causing various problems associated with core skew. It is possible to achieve the same effect as when the core is skewed or the core is skewed.

As shown in FIG. 5, which is a plan view of the linear motor of the present invention, coils 23a and 23b are wound around the stator magnetic pole units 2a and 2b, respectively, so that the stator magnetic pole units 2a and 2b have a wide structure on the outside. .

Further, the mover magnetic pole unit 1 is attached to a truck M.

As shown in FIG. 5, which is a cross-sectional view taken along the line AA' in FIG.
The trolley M to which the mover magnetic pole unit 1 is attached has wheels S.
is attached to the base B, and is movable back and forth in the direction of travel along a groove provided in the base B. Further, the stator magnetic pole unit 2 faces the movable magnetic poles with an air gap in between, and is fixed to the base B. Furthermore, in contrast to the mover magnetic pole unit 1, the stator magnetic pole unit 2 is attached to the base B by a rotating mechanism and a fixing mechanism such as a shaft 5 and a nut 6 so that the skew angle can be changed arbitrarily.

A second embodiment of the invention is shown in FIG.
FIG. 6(a) is a plan view showing the positional relationship between the mover magnetic pole unit 1 and the stator magnetic pole unit 2 showing the second embodiment of the present invention, and FIG. 6(b) is the B of FIG. 6(a). -B' line sectional view.

As shown in FIG. 6(a), the stator magnetic pole unit 2 is arranged so that all the magnetic pole teeth always overlap with the permanent magnet 11 provided in the mover magnetic pole unit 1 within the rotation adjustment range. , Thereby, a skew effect can be obtained without causing a reduction in thrust force, and there is an effect of reducing detent force.

Further, as shown in FIG. 6(b), the method of fixing the stator magnetic pole unit 2 to the base B is the same as in the first embodiment, but the mover magnetic pole unit 1 is fixed to the base B. 1
For the purpose of reinforcing the strength of the permanent magnet 11.
A movable yoke 12 is inserted between the movable elements 11 and 11, and the motor characteristics and skew effect are the same as in the first embodiment.

Furthermore, in order to downsize the entire motor, the unnecessary stator yoke 22 can be removed to create a design with a higher density magnetic circuit. Since the strength decreases, the above-mentioned mechanical strength can be increased by winding the coil 23 wound around the stator yoke 22 so as to contact the inside of the stator yoke 22 and molding it with resin.

FIG. 7 is a perspective view showing the positional relationship between the mover magnetic pole unit 1 and the stator magnetic pole unit 2 showing a third embodiment of the present invention, and in the same figure, permanent magnets 11 are arranged in a two-stage structure. The movable magnetic pole unit 1 is illustrated as an example.

FIGS. 8 to 11 show a mover magnetic pole unit 1 and a stator magnetic pole unit 2 respectively showing fourth to seventh embodiments of the present invention.
FIG.

The arrangement shown in FIGS. 8 and 9 also provides the same skew effect as in each of the embodiments described above. In addition, as shown in FIG. 10, the cart M is moved diagonally relative to the stator magnetic pole unit 2 as shown by the arrow in the figure, or as shown in FIG. 11, the movable magnetic pole unit 1 is
The same skew effect as in each of the above embodiments can also be obtained by arranging them in the same shape.

In each of the above embodiments, the case where a permanent magnet is used as the movable magnetic pole is exemplified.

Alternatively, a variable reluctance (VR) type mover may be used. In that case, it is effective to absorb not the detent force of the linear motor but the pulsation of the generated thrust.

Further, although not shown in the drawings, it goes without saying that even if both the mover magnetic pole unit 1 and the stator magnetic pole unit 2 are configured to be shifted from each other, the same effects as in each of the embodiments described above can be obtained.

Further, in each of the above embodiments, explanations regarding the winding method of the coil 23 have been omitted; however, if the coil 23 is limited in the width direction of the linear motor, the winding method shown in FIG. 6(b) may be used instead. Alternatively, the winding method may be as shown in FIG. 12, ie, the eighth embodiment of the present invention.

FIG. 13 is a plan view of a movable magnetic pole unit 1 showing a ninth embodiment of the present invention. The permanent magnets 11 are unitized and installed, and the stator magnetic pole unit 2 is attached to the movable yoke 12.
The same effects as in each of the embodiments described above can also be obtained by mounting at right angles to the above-mentioned embodiments.

〔Effect of the invention〕

As described above, according to the present invention, the detent force of a linear motor can be reduced without skewing the permanent magnets and cores used for the mover magnetic poles and the stator magnetic poles, so that it is possible to reduce the detent force of the linear motor. It can reduce man-hours, simplify linear motor manufacturing work,
Furthermore, it is excellent in terms of economic efficiency.

In addition, since the magnitude of the detent force and thrust of the linear motor can be changed by changing the mounting angle (skew angle) of the stator magnetic poles, it is possible to adapt the model to suit the application, and it is also excellent in terms of mass production. There is.

[Brief explanation of drawings]

1 to 5 show an embodiment of the present invention, FIG. 1 is a perspective view showing the positional relationship between a mover magnetic pole unit 1 and a stator magnetic pole unit 2, and FIG. 2 is a stator magnetic pole unit. 3 is a plan view of the mover magnetic pole unit 1, FIG. 4 is a plan view of the linear motor of the present invention, and FIG. 5 is a sectional view taken along the line AA' in FIG. 4. FIG. 6(a) is a plan view showing the positional relationship between the mover magnetic pole unit 1 and the stator magnetic pole unit 2 showing a second embodiment of the present invention, and FIG. FIG. 7 is a perspective view showing the positional relationship between the mover magnetic pole unit 1 and the stator magnetic pole unit 2 showing the third embodiment of the present invention, and FIGS. 8 to 11 are 12 is a plan view showing the positional relationship between the mover magnetic pole unit 1 and the stator magnetic pole unit 2, respectively showing the embodiments of FIGS. 4 to 7 of the present invention, and FIG. 12 shows the eighth embodiment of the present invention. A diagram corresponding to FIG. 6(b) shown. FIG. 13 is a plan view of a mover magnetic pole unit 1 showing a ninth embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Mover magnetic pole unit, 2... Stator magnetic pole unit, 11... Permanent magnet, 21... Stator magnetic pole tooth,
22... Stator yoke, 23... Coil.

Claims (1)

[Scope of Claims] 1. A movable magnetic pole unit having movable magnetic poles arranged at a constant pitch in the longitudinal direction, facing the movable magnetic pole unit with a slight gap therebetween, and formed of a magnetic material. 1. A linear motor comprising a plurality of stator magnetic pole units having concave and convex magnetic poles, characterized in that the mounting position of the stator magnetic pole units is skewed with respect to the phase of the magnetic poles of the mover magnetic pole unit. 2. In the invention described in claim 1, a linear motor in which the mover magnetic pole unit is a permanent magnet and N poles and S poles are alternately arranged. 3. The linear motor according to claim 1, wherein the mounting position of the mover magnetic pole unit is skewed with respect to the phase of the magnetic pole of the stator magnetic pole unit. 4. The linear motor according to claim 1, wherein the movable magnetic pole unit is constructed by arranging permanent magnets in two or more stages. 5. The linear motor according to claim 1, in which a plurality of permanent magnets are diagonally arranged as a unit with respect to the movable magnetic pole unit. 6. The linear motor according to claim 1, in which the movable magnetic pole unit is arranged diagonally with respect to the moving direction thereof. 7. The linear motor according to claim 1, in which the moving angle of the movable magnetic pole unit is at an angle other than 90 degrees with respect to the parallel line of the stator magnetic poles arranged in parallel. 8. In the invention set forth in claim 1, stator magnetic poles are arranged in parallel, and the movable element is moved in a direction perpendicular to the parallel line and oblique to the moving direction of the movable magnetic pole unit. A linear motor with magnetic poles attached to the mover. 9. In the invention according to any one of claims 1 to 8, the stator magnetic pole unit is rotatable,
A linear motor with variable skew angle of the stator magnetic pole unit. 10. The linear motor according to claim 9, wherein the mounting position of the mover magnetic pole within the rotation adjustment range of the stator magnetic pole unit overlaps with the stator magnetic pole.