JPH04101276U - Irregular moving coil - Google Patents

Abstract

(57) [Summary] [Purpose] It is possible to reduce the influence of springback etc. on the coil wire material, prevent curling and bulge, effectively ensure linearity, and also ensure sufficient length of the effective part of the coil, which is the thrust generating element. Can be secured. [Structure] The irregularly shaped moving coil C has four corner parts T by winding the coil wire 1 in one direction.
₁ , T ₂ , T ₃ , and T ₄ to form a ring. Area 1B between corner parts T ₂ and T ₃ of moving coil C
and the region 1D between T ₄ and T ₁ is the effective part of the coil,
The radii r ₂ and r ₄ of the corner portions T ₂ and T ₄ are 2d or more, preferably 3d or more with respect to the diameter d of the coil wire 1, and are larger than the radii r ₁ and r ₃ of the other corner portions. be done.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is mainly used for rotary voice coil motors (VCM). This relates to moving coils.

0002

[Conventional technology]

A moving coil C mainly used in a rotary type VCM is usually made by winding a coil wire in a circular shape via four corner parts T ₁ , T ₂ , T ₃ , and T ₄ as shown in Fig. 4. The motor drive force is obtained by the current flowing through the straight part of the coil corresponding to the arc-shaped magnet M. The purpose of such a moving coil C is to prevent the coil wire 1 from being pressed against the corners of the winding jig and be damaged at the corner parts T ₁ , T ₂ , T ₃ , T ₄ during winding, and to prevent the magnet M from being damaged. In order to prevent "bulging" in the straight section of the coil that crosses the corner, the inside of the corner section is configured to form a curved surface with an appropriate radius r.

0003

[Problem that the idea aims to solve]

However, if this radius of curvature r is set large, a linear curve that crosses the magnet M The effective length of the file becomes shorter. However, if the radius of curvature r is set small, the book Since then, in the effective part of the coil where linearity is required, "winding" due to the elasticity of the coil wire 1 has been The effective part of the coil expands outward and reciprocates within a predetermined angle. This results in a decrease in the generated torque on both sides of the swing region, making it difficult to obtain thrust linearity. This causes problems such as:

0004 Therefore, the purpose of the present invention is to increase the radius of the required corner. So, while ensuring the straight line length of the effective part of the coil as much as possible, To provide an irregularly shaped moving coil that can maintain its properties.

[0005]

[Means to solve the problem] The above object is achieved by the irregularly shaped moving coil according to the present invention. Let's summarize For example, the present invention has a plurality of corner parts and is formed by winding in a ring for VCM. In the cutting coil, the corners at both ends of the coil area where linearity is required are The inner radius of the corner on the winding start side is larger than the inner radius of the other corners. This is an unusually shaped moving coil characterized by the following.

[0006]

【Example】

Below, the irregularly shaped moving coil according to the present invention will be explained in more detail with reference to the drawings. . Referring to FIGS. 1 and 2, in this embodiment, the irregularly shaped moving coil C is By winding the coil wire 1 counterclockwise in the figure, four corner parts T are formed. ₁ , T₂ , T₃ , T_Four It shall be formed into an annular shape via.

[0007] In this case, according to the present invention, the corners of the winding jig used for winding, that is, the movie Corner part T of coil C₁ , T₂ , T₃ , T_Four The inner corners of each have a radius of r₁ , r₂ , r₃ , r_Four , especially the corner part T₁ , T₂ area between 1A and T₃ , T_Four In the region 1C between the coil wires 1, even if there is a bulge in the coil, , since it does not affect performance, the corner part T₁ and T₃ In this case, the coil wire 1 is folded. The radius is small enough to avoid damage such as loss. Corner part T₁ and T ₃ radius r₁ and r₃ are the hardness of coil wire material 1, winding tension, and guide roller. Although it depends on the winding conditions such as the position, it is usually comparable to the diameter d of the coil wire 1. The corresponding size, i.e., r₁ =r₃ =d. The coil wire material 1 used is rectangular. If it is a rectangular material with a cross section, the size corresponds to its thickness t, that is, r₁ =r₃ =t is set to

[0008] On the other hand, the corner portion T of the moving coil C₂ , T₃ Area 1B and T between_Four , T ₁ The area 1D in between is an effective portion of the coil, and the coil wire 1 requires linearity. Therefore, according to the present invention, each corner portion T₂ and T_Four The inner corner of the coil wire 1 is sufficiently wound along the curved surface of the winding jig, and the coil wire 1 is wound in areas 1B and 1D. maintains straightness and prevents curling and bulges. Normally corner part T₂ Reach BiT_Four radius r₂ and r_Four are the hardness of coil wire material 1, winding tension, and guide rod. The diameter d or thickness of the coil wire 1 depends on the winding conditions such as the position of the coil wire. It is set to be 2d (2t) or more, preferably 3d (3t) or more with respect to s t. radius r₂ and r_Four may have the same size or may have different sizes.

[0009] With this configuration, strictly speaking, the shape of the moving coil C is symmetrical. However, according to the inventors' experimental results, there is no problem in practical use, and the low Achieving the linearity of thrust required for the moving coil of a tally-type VCM. I understand.

To explain further, in FIG. 3, if the winding thickness of the moving coil C according to the present invention is W and the length of the effective part is L, the coil wire 1 is a wire with a diameter of 0.32 mm. When turning, r ₁ = r ₂ = r ₃ = r ₄ = 0.32 mm In the conventional coil, W = 5.4 mm and L = 20 mm, but r ₁ = r ₃ = 0.32 mm. , r ₂ = r ₄ = 0.64 mm, W = 5.2 mm, L = 18 mm.

[0011] The moving coil C of this invention has a smaller W and a smaller winding bulge than the conventional type. I know what's wrong. Also, according to the present invention, although the effective length L is somewhat shortened, it is substantially shorter. It is possible to maintain sufficient effective length without reducing the extent that it affects performance.

0012

[Effect of the idea]

As explained above, the irregularly shaped moving coil according to the present invention ensures linearity. Of the corners on both ends of the part that needs to be rolled, the inner half of the corner on the side where the winding starts. Since the diameter is configured to be larger than the inner radius of the other corners, the coil wire There is little effect of springback of the material, prevents curling and bulging, and effectively straightens the material. In addition, the effective length of the coil, which is the thrust generating element, can be ensured sufficiently. It can have the practical effect of being able to

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the irregularly shaped moving coil of the present invention.

FIG. 2 is an enlarged view of essential parts of the irregularly shaped moving coil in FIG. 1;

FIG. 3 is a front view showing an embodiment of the irregularly shaped moving coil of the present invention.

FIG. 4 is a front view of a conventional moving coil.

[Explanation of symbols]

1: Coil wire T _1, T _2, T _3, T ₄ : Corner part r ₁ , r _2, r _3, r ₄ : Radius of coil corner part

Claims (1)

[Scope of utility model registration request] 1. In a VCM moving coil formed by winding annularly and having a plurality of corner portions, among the corner portions at both ends of the coil region that require linearity,
An irregularly shaped moving coil characterized in that the inner radius of the corner portion on the winding start side is larger than the inner radius of the other corner portions.