JP2008245399A - Shaft type linear motor armature, shaft type linear motor, and manufacturing method of shaft type linear motor armature - Google Patents

Abstract

A linear motor capable of increasing motor thrust, reducing cogging, and improving motor efficiency.
A plurality of ring-shaped cores 8 are sequentially arranged along the driving direction of the linear motor, and a ring-shaped coil 7 is arranged between the ring-shaped cores 8 along the driving direction of the linear motor. In the linear motor armature structure in which the bracket 13 is disposed on the outer peripheral side of the ring-shaped core 8, the inner periphery of the ring-shaped core 8 has a convex portion 8 a having an inner diameter substantially equal to the inner diameter of the ring-shaped coil 7, A concave portion 8 b having an inner diameter larger than the inner diameter of the ring-shaped coil 7 is formed.
[Selection] Figure 1

Description

  The present invention relates to a structure of a shaft type linear motor, and more particularly to an armature structure thereof.

  Conventionally, as this type of linear motor, a magnetic field portion in which N-pole and S-pole magnetic poles are alternately arranged inside a cylindrical pipe extending in the axial direction, and a magnetic gap on the outer periphery of the field portion. A concentric arrangement and an armature in which a plurality of ring-shaped coils are provided in the axial direction on the inner periphery of a cylindrical yoke is shown (for example, see Patent Document 1). In such a linear motor, one of the field part and the armature is a mover, and the other is a stator.

JP 2006-223090 A

  In the above-described linear motor armature, by disposing a ring-shaped core made of a magnetic material between ring-shaped coils disposed in the axial direction, the energy density is increased and the thrust of the linear motor is further increased. be able to. However, such a structure has the following problems.

That is, in the armature of placing a ring-shaped core during the ring-shaped coil, the inner diameter of the ring-shaped coil: with d _1, the inner diameter of the ring-shaped core: relation between d ₂ is set to be the d _{1 <d 2} It has been elucidated by numerical analysis and the like that cogging can be reduced. Method of manufacturing an armature of this case, the outer diameter of the ring-shaped coil: If the outer diameter D ₂ of the D ₁ and the ring-shaped core Oke set to D _{1 =} D _2, the outer diameter D _1, D ₂ equal to the inside diameter (hole ) Is prepared, and the armature can be configured by alternately inserting ring coils and ring cores into the holes of the brackets. However, when assembling the armature, in order to prevent the ring-shaped coil from collapsing, it is formed by wrapping a copper wire around a bobbin or having a self-bonding layer coating on the copper wire forming the coil. It is necessary to fix the coil by energizing and heating the coil.

  In the former case, since the copper wire is wound around the bobbin, the coil inner diameter increases by the thickness of the bobbin. For this reason, the magnetic gap with the field portion is increased, so that the magnetic resistance is increased and the thrust is reduced accordingly. In the latter case, there is a problem that the energization heating process increases and the manufacturing cost increases.

Separately from the armature structure and assembly method described above, a ring-shaped core is fitted in advance to the winding core with a predetermined pitch, a coil is formed by winding a copper wire between the ring-shaped cores, and these are molded. There is a method of configuring an armature by pulling out a winding core after hardening with resin. However, in this method, the inner diameter of the ring-shaped core needs to be the same as the outer diameter of the winding core, and the effect of reducing cogging cannot be achieved by setting d ₁ <d ₂ .

  The present invention has been made to solve the above-described conventional problems, and provides a linear motor that can increase motor thrust, reduce cogging, and improve motor efficiency.

  The armature of the shaft type linear motor according to the present invention includes a plurality of ring-shaped cores sequentially arranged along the driving direction of the linear motor, and is disposed between the ring-shaped cores and along the driving direction of the linear motor. A ring-shaped coil, and a bracket disposed on the outer peripheral side of the ring-shaped coil and the ring-shaped core, the inner periphery of the ring-shaped core having a convex portion whose inner diameter is substantially equal to the inner diameter of the ring-shaped coil; Has a recess larger than the inner diameter of the ring coil.

The method of manufacturing an armature for a shaft type linear motor according to the present invention includes the above-described ring having a convex portion whose inner diameter d ₁ is substantially equal to the inner diameter of the ring-shaped coil and a concave portion whose inner diameter d ₂ is larger than the inner diameter of the ring-shaped coil. the Jo core, placing at a predetermined space a winding core having an outer diameter substantially equal to D and inner diameter d _1, by winding the winding space of the winding core, the inner diameter between the ring-shaped core Forming a ring-shaped coil in which d is substantially d ₁ and applying a resin mold to the ring-shaped coil formed on the core and the ring-shaped core, and then extracting the core to form a coil assembly. It is provided.

  According to the armature of the shaft type linear motor of the present invention, the ring-shaped core and the ring-shaped coil are alternately arranged along the driving direction of the linear motor. The gap between the inner diameter of the ring-shaped coil and the inner diameter of the ring-shaped core required for cogging reduction is equivalent Can be formed. As a result, it is possible to provide a linear motor that can increase motor thrust, reduce cogging, and improve motor efficiency.

Further, according to the shaft-type production method of a linear motor armature according to the present invention, the inner circumference of the ring-shaped core, substantially equal to the convex portion inner diameter d ₁ is the inner diameter of the ring-shaped coil, the inner diameter d ₂ rings It is prepared having a larger recess inner diameter of Jo coil, with arranging a ring-shaped core a winding core having an outer diameter substantially equal to D and inside diameter d ₁ with a predetermined space, the winding space of the winding core Is used to form a ring-shaped coil having an inner diameter of approximately d ₁ between the ring-shaped cores, thus simplifying the manufacturing process of a shaft-type linear motor that has a large motor thrust and can reduce cogging. In addition, the manufacturing cost can be reduced.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

Embodiment 1 FIG.
1 is a side sectional view showing a shaft-type linear motor according to Embodiment 1 of the present invention, and FIG. 2 is a sectional view taken along line II-II in FIG.

  1 and 2, a shaft type linear motor 100 is arranged with a cylindrical field portion 1 extending in the driving direction of the linear motor and a predetermined gap around the outer periphery of the field portion 1. A cylindrical armature portion 6 is provided. In the case of the present embodiment, the field part 1 functions as a mover of the linear motor, and the armature part 6 functions as a stator of the linear motor.

  The field part 1 includes a stepped shaft 2 extending in the linear motor driving direction, a ring-shaped magnet 3 formed by alternately inserting N-pole magnets and S-pole magnets into the stepped part 2a of the stepped shaft 2, A shaft 4 fixed to one end of the stepped shaft 2 is provided. The field magnet portion 1 is assembled by inserting a plurality of ring-shaped magnets 3 into the stepped portion 2a of the stepped shaft 2 extending in the driving direction of the linear motor so that the north and south poles are alternately arranged. The plurality of ring-shaped magnets 3 are attached to the opposite shaft 4 for pressing the ring-shaped magnet 3 from the opposite side of the stepped shaft 2 in order to repel each other. The opposite shaft 4 and the stepped shaft 2 may be fixed by press-fitting or adhesion in addition to fixing by screwing. The repulsion of the ring-shaped magnet 3 can be suppressed by fixing the opposite shaft 4.

  In the armature portion 6, a plurality of ring-shaped cores 8 are sequentially disposed in the linear motor driving direction (shaft axial direction), and a ring-shaped coil 7 is disposed between the ring-shaped cores 8. Yes. The inner periphery of the ring-shaped coil 7 and the outer periphery of the ring-shaped magnet 3 of the field magnet portion 1 have a predetermined magnetic gap 9. On the inner periphery of the ring-shaped core 8, convex portions 8 a having the same inner diameter as the inner diameter of the ring-shaped coil 7 and concave portions 8 b having an inner diameter larger than the inner diameter of the ring-shaped coil 7 are alternately formed. That is, as shown in FIG. 2, convex portions 8 a and concave portions 8 b are alternately formed in a gear shape on the inner periphery of the ring-shaped core 8. In the present embodiment, three convex portions 8 a and three concave portions 8 b of the ring-shaped core 8 are disposed at symmetrical positions around the axis of the field portion 1. Further, at least one recess 10 is disposed on the outer periphery of the ring-shaped core 8.

  The ring-shaped coil 7 and the ring-shaped core 8 are integrated with a resin mold 11 to form a coil assembly (COIL ASSY) 12. A protective bracket 13 is disposed on the outer periphery of the coil assembly 12. The coil assembly 12 is fixed to the bracket 13 by being press-fitted or shrink-fitted into the inner periphery of the bracket 13. Bearing holders 14 are attached to both ends of the bracket 13 by screws, and the bracket 13 and the bearing holder 14 are fixed. A bearing 15 such as a sliding bearing or a ball bush is attached to the bearing holder 14 and supports the field portion 1 so as to be slidable. The bearing holder 14 is also effective in preventing the coil assembly 12 disposed in the bracket 13 from coming off in the axial direction by being sandwiched from both ends of the bracket 13. The bracket 13 is provided with a mounting hole (not shown), and this mounting hole and a fixed-side mounting base (not shown) are fixed with screws and used as a shaft type linear motor.

  Next, a method for manufacturing the coil assembly 12 will be described. As shown in FIG. 3, a plurality of ring-shaped cores 8 are arranged on a cylindrical core 16 having an outer diameter D with a predetermined space 17 therebetween. And the ring-shaped coil 7 is formed by setting a copper wire in each space 17 (17a-17l) between the ring-shaped core 8, rotating the winding core 16 in a winding direction, and winding up a copper wire. . As shown in FIG. 4, the U-phase coil is in spaces 17a, 17d, 17g, and 17j, the V-phase coil is in spaces 17b, 17e, 17h, and 17k, and the W-phase coil is in spaces 17c, 17f, 17i, and 17l. Is wound on. Further, when it is desired to increase the stroke of the linear motor, it can be easily handled by increasing the number of the three-phase ring coils 7 in the axial direction. The coiled copper wire wound in each space 17 has the ring-shaped cores 8 adjacent to both sides as side walls, and even if it is a coiled copper wire wound in multiple layers, the coiled copper wire can be easily formed. It is.

  After winding the coil copper wire in all the spaces 17, the ring-shaped coil 7 and the ring-shaped core 8 formed on the core 16 are assembled to a molding jig (not shown), and a resin mold as shown in FIG. 11 to harden. After the resin mold 11 is applied, the coil assembly 12 as shown in FIG.

FIG. 7 shows a sectional view of the coil assembly 12 of FIG. 7, the inner diameter of the convex portion 8a having an inner diameter of the ring-shaped core 8 of the ring-like coil 7 are both substantially equal d _1, is set to be substantially equal to the outer diameter D of the winding core 16 (D = D ₁ ). The inner diameter of the recess 8b of the ring-shaped core 8 is _{d 2,} is set to be larger than the inner diameter _{d 1} of the convex portion _{8a (d 2> d 1)} . A protective bracket 13 is fixed to the outer periphery of the coil assembly 12.

  In the above embodiment, the surface of the ring-shaped core 8 is subjected to cationic electrodeposition coating using, for example, an epoxy-based paint to ensure insulation from the coil copper wire. The ring coils 7 having the same phase are connected to each other via a jumper wire 18. Further, as shown in FIG. 7, the connecting wire 18 is arranged and guided inside the recess 10 provided on the outer peripheral side of the ring-shaped core 8.

  As described above, according to the present embodiment, the ring-shaped core and the ring-shaped coil are alternately arranged along the linear motor driving direction, and the inner diameter of the ring-shaped core is the ring-shaped coil. The gap between the inner diameter of the ring-shaped coil and the inner diameter of the ring-shaped core, which is necessary for reducing cogging, is equivalently formed by forming a convex portion approximately equal to the inner diameter of the ring and a concave portion whose inner diameter is larger than the inner diameter of the ring-shaped coil. be able to. As a result, it is possible to provide a linear motor that can increase motor thrust, reduce cogging, and improve motor efficiency.

Further, the inner periphery of the ring-shaped core, substantially equal to the convex portion inner diameter d ₁ is the inner diameter of the ring-shaped coil, an inner diameter d ₂ is prepared having a recess larger than the inner diameter of the ring-shaped coil, the inner diameter d _A ring-shaped core is disposed on a winding core having an outer diameter D substantially equal to ₁ with a predetermined space therebetween, and a winding is wound in the space of the winding core so that the inner diameter is approximately d between the ring-shaped cores. _{Since the} ring-shaped coil that is ₁ is formed, the manufacturing process of the shaft type linear motor that has a large motor thrust and can reduce cogging is simplified, and the manufacturing cost can be reduced.

  Further, by arranging the convex portions and concave portions on the inner periphery of the ring-shaped core alternately and at equal intervals along the inner periphery of the ring-shaped core, it is possible to eliminate the unbalance of the attractive force. This has the effect of reducing the load on the bearing that supports the shaft and extending the service life.

  In addition, by providing at least one recess on the outer periphery of the ring-shaped core, it is possible to guide the connecting wire of the in-phase coil, enabling continuous winding of the in-phase coil, reducing the number of connections and reducing manufacturing costs. can do.

  In the description of the embodiment, an example in which the field unit 1 is a linear motor mover and the armature unit 6 is a linear motor stator is shown. However, the field unit is a linear motor stator. It is obvious that the same effect can be obtained even in a structure in which the armature portion 6 is a mover of a linear motor.

It is a sectional side view which shows the shaft type linear motor by Embodiment 1 of this invention. It is a longitudinal cross-sectional view which shows the shaft type linear motor by Embodiment 1 of this invention. It is a sectional side view which shows the state which attached the ring-shaped core to the winding core by Embodiment 1 of this invention. It is a sectional side view which shows the state which gave the coil | winding to the winding core by Embodiment 1 of this invention. It is a sectional side view which shows the state after the mold by Embodiment 1 of this invention. It is a sectional side view which shows the coil assembly by Embodiment 1 of this invention. It is a longitudinal cross-sectional view which shows the coil assembly by Embodiment 1 of this invention.

Explanation of symbols

100 linear motor, 1 field part, 2 stepped shaft, 3 ring magnet,
6 armature part, 7 ring coil, 8 ring core, 8a convex part, 8b concave part,
11 resin mold, 12 resin mold, 13 bracket, 16 core,
17 space.

Claims (6)

A plurality of ring-shaped cores sequentially arranged along the driving direction of the linear motor;
A ring coil disposed between the ring cores and disposed along the driving direction of the linear motor;
The ring-shaped coil and a bracket disposed on the outer peripheral side of the ring-shaped core,
An armature of a shaft type linear motor in which a convex portion whose inner diameter is substantially equal to the inner diameter of the ring-shaped coil and a concave portion whose inner diameter is larger than the inner diameter of the ring-shaped coil are formed on the inner periphery of the ring-shaped core . 2. The shaft-type linear motor according to claim 1, wherein the convex portions and the concave portions formed on the inner periphery of the ring-shaped core are provided alternately and at equal intervals along the inner periphery of the ring-shaped core. Armature. The armature of the shaft type linear motor according to claim 1 or 2, wherein at least one recess is provided on an outer periphery of the ring-shaped core. The armature of the shaft type linear motor according to any one of claims 1 to 3, wherein an electrodeposition coating for insulation is applied to a surface of the ring-shaped core. 5. The shaft-type linear motor armature according to claim 1, and a field magnet in which N poles and S poles are alternately arranged along a driving direction of the linear motor. A shaft type in which the ring-shaped coil of the armature and the inner periphery of the ring-shaped core and the field magnets of the field-portion are arranged with a predetermined magnetic gap. Linear motor. A method of manufacturing an armature of a shaft type linear motor in which ring-shaped cores and ring-shaped coils are alternately arranged along the driving direction of the linear motor,
A ring-shaped core having a convex portion whose inner diameter d ₁ is substantially equal to the inner diameter of the ring-shaped coil and a concave portion whose inner diameter d ₂ is larger than the inner diameter of the ring-shaped coil is an outer diameter D substantially equal to the inner diameter d _1. A step of disposing a predetermined space on the core having
Forming a ring coil having an inner diameter of approximately d ₁ between the ring cores by winding a winding in the space of the core;
Manufacture of an armature for a shaft type linear motor comprising a step of resin molding the ring-shaped coil formed on the winding core and the ring-shaped core, and then removing the winding core to form a coil assembly. Method.

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