JPH01158629A - Actuator - Google Patents

Abstract

PURPOSE:To heighten reliability with high performance by providing a magnet multipole-magnetized in a radial direction and having a magnetization boundary in a peripheral direction and an axis direction, yokes having magnetic poles facing to the magnetization boundary and coils wounded on them. CONSTITUTION:A magnetic pole W and a magnetic pole Y are the ends of a yoke 106 and a magnetic pole X and a magnetic pole Z are the ends of a yoke 107, when the same pole of a magnet 101 faces the two magnetic poles of the same yoke, repulsion is generated, therefore, the neutral holding of a movable part can be attained. When an objective lens 103 is set in the position facing to the magnetic pole W or Y, a space through which a laser beam is passible is obtained between the magnetic poles (W, Y) for focusing and the magnetic poles (X, Y) for tracking and by setting a reflecting mirror 108, a thin structure is attained. A coil 109 wound on the yoke 106 is for focusing control and coil 110 wound on the yoke 107 is for tracking control and when a control current is supplied so as to generate the same poles at the two poles of the same yoke, the magnet is shifted minutely near the neutral position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a magnet movable two-dimensional (around an axis (θ) and in an axial direction (Z), hereinafter referred to as θ-2) actuator.

[Prior Art] Conventionally, for example, a θ-2 actuator for driving an objective lens of an optical head in an optical memory device has been disclosed in Japanese Patent Laid-Open No. 57
Many of them were of the movable coil type, as described in Japanese Patent No. 210456 and the like. In addition, as a magnet movable objective lens actuator, Japanese Patent Application Laid-Open No. 63-37830
There are some publications etc.

[Problems to be Solved by the Invention] However, in the case of a movable coil actuator in the prior art, disconnection of the power supply line to the movable coil, poor adhesion due to overheating of the coil, and accompanying thermal deformation of the coil are likely to occur. Further, the process of connecting the power supply line is complicated and time-consuming, and depending on the power supply method, the power supply line itself has the problem of adversely affecting the high-speed operation of the movable part. In addition, variations in the coil shape tend to cause an imbalance in the mass of the movable part, which causes high-order resonance and other problems that impede high-speed operation. Therefore, in the case of an optical memory device, the rotation speed of the optical disk cannot be increased, and the data transfer speed is limited. Furthermore, since changes in coil specifications (number of turns, wire diameter, etc.) lead to changes in the mass of the movable part, it is necessary to repeatedly cut and try with changes in the design of the actuator in order to find the optimum specifications for the coil.

On the other hand, in the case of a movable magnet actuator, the structure is complicated, such as requiring multiple magnets and magnetic circuits to realize two-dimensional operation. Therefore, mass imbalance of the movable part is likely to occur, and in addition, the increased weight of the movable part has a negative effect on high-speed response, and furthermore, there are problems in that the cost increases.

Therefore, the present invention is intended to solve these problems, and its purpose is to achieve high-speed operation by creating a structure in which the mass of the moving parts is well balanced and there is no need to supply power to the moving parts. Our goal is to provide superior actuators. By applying this actuator to, for example, an objective lens actuator, it becomes possible to realize an optical memory device with high reliability and a high data transfer rate.

[Means for Solving the Problems] The actuator of the present invention is an actuator that is rotatable around a support shaft and movable linearly in the axial direction of the support shaft, (a) multipolar magnetization is applied in the radial direction. (b) a yoke having a magnetic pole facing the magnetized boundary; and a coil wound around the yoke. .

This multi-pole magnetized cylindrical magnet becomes a moving part, so the thinner the wall, the lighter the weight. Therefore, it is very effective to use resin-bonded magnets, which have good productivity and workability. Sm--Co resin-bonded magnets with high performance are particularly effective. In addition, those in which a part of Sm is replaced with at least one kind of light rare earth metal mainly consisting of Nd, Ce, and Pr, and R-Fe
-B resin-bonded magnets can also provide sufficient magnetic properties and are advantageous in terms of raw material supply and cost.

Furthermore, by using a high-performance R-Fe-B magnet, the drive characteristics of the actuator are improved. Furthermore, R, F
e, BS A sintered magnet whose basic composition is Zr can also provide sufficient magnetic properties and is advantageous in terms of raw material supply and cost.

Further, by using an R-M-X cast magnet, a low-cost, high-performance actuator can be constructed.

The actuator of the present invention has excellent high-speed operation of θ-2,
Since it can be easily made smaller and thinner, it is very suitable for an objective lens actuator that performs focusing and tracking operations in optical memory devices. Also,
It can also be applied to precision positioning devices in the manufacture of semiconductor integrated circuits.

[Operation] The actuator of the present invention moves the magnet straight in the axial direction of the support shaft by the attractive and repulsive forces between a cylindrical magnet that is multi-pole magnetized in the radial direction and magnetic poles that oppose the magnetized boundary in the circumferential direction. make it move. Further, the magnet is rotated around the support shaft by the attractive force and repulsive force between the magnet and the magnetic pole facing the magnetized boundary in the axial direction. In this way, it is possible to drive in two dimensions of θ-2 with − number of magnets.

[Example] The present invention will be described in detail below based on examples.

(Example-1) Figures 1 (a), (b), and (C) are schematic configuration diagrams when the actuator according to an embodiment of the present invention is used as an objective lens actuator, and (a) is a plan view; b) is a front view, and (C) is a sectional view. The magnet 101 has a cylindrical shape. Regarding magnet dimensions (inner diameter, outer diameter, height),
I will explain later. A plastic lens frame 102 is fixed inside the magnet, and the center of the frame is a bearing. Incidentally, as shown in FIG. 2, it is also possible to use a separate plastic sleeve 201 as a bearing. A yoke ring 301 may be inserted between the magnet 101 and the lens frame 102 as a back yoke, as shown in FIG. Objective lens 103 is lens frame 102
The objective lens mount is fixed to the part, rotates around a support shaft 105 erected on a base 104, and moves directly in the axial direction of the support shaft, making it possible to move the focal point of the laser beam two-dimensionally. ing. FIG. 4 is a developed view of the magnet showing the magnetization pattern of the magnet. Details of the magnetization method will be described later. Multipolar magnetization is applied in the radial direction of the cylinder, and N and S poles appear on the magnet surface as shown in FIG. Although the area ratios are set to be approximately the same due to ease of magnetization, the invention is not limited to this, and it is sufficient that the magnetic poles of the yokes face the magnetization boundaries. The symbols W, X, y, and Z in the figure correspond to the symbols in FIG. 1(a), and indicate the opposing positions of the respective magnetic poles.

The magnetic poles W and y are the ends of the yoke 106, and the magnetic poles X and 2 are the ends of the yoke 107. When the same pole of the magnet 101 tries to oppose two magnetic poles of the same yoke, a repulsive force is generated, so the position where the magnetized boundary faces the magnetic poles is the most stable, and the movable part can be maintained neutrally. There is no need for additional springs. As shown in FIG. 1(a), the width of the magnetic poles is such that X and 2 are narrower than W and y, and the width of the magnetic pole is narrower than that of W and y.
If it is set at a position facing the magnetic pole W or y as shown in Figure 1, there will be enough space between the focusing magnetic poles (w, y) and the tracking magnetic poles (X, Z) for the laser beam to pass through. By installing the reflecting mirror 108 as shown in FIG. 1, a thin structure can be obtained. Coil 109.
110 are the yokes 106 . . . , respectively, as shown in FIG.
It is wrapped in 107. As shown in FIG. 1(b), a coil 109 wound around the yoke 106 is used for focusing control (the coil 110 for tracking control is not shown).
, as shown in FIG. 1(C), the coil 110 wound around the yoke 107 is for tracking control (the coil 109 for focusing control is not shown), and the same polarity occurs in the two magnetic poles of the same yoke. When a control current is applied so as to cause the magnet to slightly displace near its neutral position. Note that there is no particular restriction on whether to wind the coil directly around the yoke or to use a coil bobbin. However, if you wrap it directly around the yoke,
Needless to say, sufficient insulation treatment is required.

This embodiment is easy to assemble because a support member such as a spring is not used to maintain the movable part neutrally, and high-order resonance of the support member, which has been a problem with conventional actuators, can be avoided.

Furthermore, the mass distribution of the movable parts can be accurately grasped at the time of design, a structure with good mass balance can be realized, and stable high-speed operation can be achieved. In conventional coil movable actuators, variation in coil shape causes mass imbalance in the movable part, causing unnecessary parasitic imaging and states slip on the bearing sliding surface, but this example solves these problems. points are avoided.

In addition, the conventional movable magnet actuator requires a plurality of magnets to be combined and has a complicated structure, making it difficult to assemble, but the actuator of this embodiment is easy to assemble.

Since the actuator of this example does not have a coil in the gap between the magnet and the magnetic pole, it is possible to make the gap extremely small by increasing the dimensional accuracy of the magnet.
Good current-thrust (torque) characteristics and high efficiency.

The magnet used in this example is preferably lightweight and has high performance, and a suitable magnet will be described in detail later, including its manufacturing method.

(Example-2) Next, an example of the side structure will be described.

Although the structure of the magnetic circuit is not limited to (Embodiment 1) and various examples can be considered, FIG. 5 shows a schematic perspective view of a case where an independent magnetic circuit structure is provided for each magnetic pole.

The structure of each magnetic circuit is as shown in FIG.
01 has magnetic poles on the inside and outside and the yoke 602 is integrated, as shown in Fig. 6(b), the yoke is not integrated but separated, as shown in Fig. 6(C). It is conceivable that there are magnetic poles only on the outside. Both configurations are provided with appropriate springs, dampers, etc. (not shown) to maintain the movable portion neutrally. In addition, when the magnetic poles of all magnetic circuits are provided only on the outside of the magnet as shown in Figure 6 (C), efficiency can be improved by fixing a yoke ring inside the magnet as shown in Figure 3. can be improved. In addition to the example shown in FIG. 4, the magnetization pattern of the magnet can also be patterned as shown in FIGS. 7(a) and 7(b).

In this embodiment as well, the mass balance of the movable part is good, and the gap between the magnet and the magnetic pole can be made small.

As mentioned above, in both Examples 1 and 2, there is no need for a power supply line to the movable part,
Assembly is easy because there is no need to worry about wire breakage, and there is no need to connect the power supply line. Furthermore, there is no need to worry about thermal deformation of the coil or poor adhesion.

A method for manufacturing the multi-pole magnetized cylindrical magnet used in Examples 1 and 2 will be described below. The raw materials for rare earth metals (R) shown in this example have a total R of 99.
The purity used was 8% or more, and the purity of the main R was 99% or more.

FIG. 8 is a manufacturing process diagram of a Sm-Co resin bonded magnet. It was made into a cylindrical shape by compression molding method (a), injection molding method (b), and extrusion molding method (C).

It is desirable that the cylindrical magnet, which is a component of the present invention, be made radially anisotropic in order to perform multipolar magnetization in the radial direction. Therefore, an Sm--Co resin-bonded magnet that can produce radially anisotropic magnets with high productivity is very advantageous. In addition, its high magnetic performance allows the movable part to be made smaller and lighter.

Furthermore, since high dimensional accuracy can be easily achieved, the gap between the magnet surface and the magnetic pole can be narrowed. First, the composition is S
m (Coll, av2cus, @aF ea, ztZ
r@, 52B) The raw material is melted in an induction furnace to give e, 3s, and the ingot is heated at 112 in an Ar gas atmosphere.
Solution treatment was performed at 0 to 1180°C for 5 hours, and further 8
Aging treatment was performed at 50°C for 4 hours. The 2-17 rare earth intermetallic alloy thus obtained has an average grain size of 2.
A magnet composition prepared by pulverizing the powder to 0 μm (by Fischer subsieve cider) and mixing 1% thermosetting two-component engineered poxy resin 2 weight as a binder with 98% by weight of the powder was powder-molded. After being radially oriented in a magnetic field and molded into a cylindrical shape using a magnetic field press device, a curing treatment was performed (Fig. 8 (a), magnet A). By using this compression molded magnet, an objective lens actuator with excellent high-speed response can be easily produced. In addition, a 2-17 rare earth intermetallic alloy obtained by the same method as above was pulverized to an average particle size of 20 μm, and 40 vol.% of nylon-12 was added as a binder to 60 vol.% of this powder. The mixed magnet composition was radially oriented in a magnetic field using an injection molding device, molded into a cylindrical shape, and then annealed (
Figure 8 (b), magnet B). In addition, a 2-17 rare earth intermetallic alloy obtained by the same method as above was pulverized to an average particle size of 20 μm, and this magnetic powder was 92 times 1
% and a magnet composition consisting of 8% by weight of nylon-12,
After kneading at 200°C, the raw material compound was granulated to an outer diameter of 3 to 6 mm, and was radially oriented in a magnetic field using an extrusion molding device and molded into a cylindrical shape (Fig. 8 (C)
), magnet C).

These injection molded magnets and extrusion molded magnets have somewhat lower magnetic performance than compression molded magnets, but have higher productivity. In particular, extrusion-molded magnets can be very easily formed into extremely thin-walled cylindrical shapes.

The objective lens actuator using this injection molded magnet or extrusion molded magnet can be fully applied to read-only or optical memory devices with low optical disk rotation speeds.

A Nd-Ce substituted Sm-Co resin-bonded magnet was molded in the same manner as the compression molding shown in FIG. The composition is S ma
,sN da,4Ce a,+ (Co e,et2c
u tl, 98F e 11.22Zrs, 52s)
The 2-17 rare earth intermetallic alloys s and ss were pulverized to have an average particle size of 80 μm. To 98% by weight of this powder, 2% by weight of a thermosetting two-component engineered poxy resin was added as a binder and mixed. This magnet composition was radially oriented in a magnetic field and molded into a cylindrical shape using a powder compacting magnetic field press apparatus, and then cured (Magnet D). This Nd
-Ce-substituted Sm-Co resin bonded magnet has Nd, Ce
Although the magnetic performance is somewhat lower than that without substitution, it is advantageous in terms of raw material supply and price. In addition, sufficient magnetic properties can be obtained even when a part of Sm is replaced with Pr (magnet E).
This is also advantageous in terms of raw material supply and price. Sufficient high-speed operation was also confirmed when these magnets (D, E) were used.

FIG. 9 is a manufacturing process diagram of a Nd-Fe-B resin bonded magnet. N d +sF e 82.7B 4.
A ribbon with a mixed state of crystal and amorphous is created using the alloy with the composition 3(7) using the melt-spun method, and the magnetic powder obtained by crushing this is mixed and kneaded with an epoxy resin, which is then shaped into a cylindrical shape. After pressure molding, curing treatment was performed (magnet F). Since this Nd-Fe-B resin-bonded magnet can be manufactured with good workability, it is advantageous in terms of cost and raw material supply to use it in the actuator of the present invention.

FIG. 10 is a manufacturing process diagram of a Nd-Fe-E magnet. N d 13F e 82. A ribbon with a mixed state of crystal and amorphous was created using an alloy with the composition of TB 4.3 using the melt-spun method, and the ribbon was crushed and the resulting magnetic powder was placed in a cylindrical mold and subjected to hot consolidation treatment. (10th
Figure (a), magnet G). This magnet is made of the above Nd-Fe
- Excellent magnetic performance can be obtained because the packing density of magnetic powder is higher than that of B-based resin bonded magnets. Furthermore, after the step (a), a radially anisotropic magnet is obtained by applying pressure in the radial direction of the cylinder while heating (Fig. 10 (b), magnet H), and a Nd-Fe-B based magnet. The original high magnetic properties of the magnet can be fully brought out. By using the Nd-Fe-B magnets (G, H) obtained in this way, an actuator with excellent high-speed response can be obtained.

FIG. 11 is a manufacturing process diagram of a sintered magnet whose basic composition is R, Fe, B, and Zr. Z r2.6 (C
ell, 2P r s, 2N d e, e) +2. s
A powder obtained by melting and casting the magnet raw material to become F e e e B v in an Ar gas atmosphere using a high frequency melting furnace, and pulverizing it with a stamp mill/ball mill so that the average particle size is 3 to 5 μm, Filled into a cylindrical mold and heated to 15kO
radially aligned in a magnetic field of 15-20 kg/
Pressure molding was performed at a molding pressure of m m 2, and then Ar
Sintered magnets are sintered in a gas atmosphere at an optimal temperature of 1000-1250°C, and if necessary, heat treated at an optimal temperature of 400-1250°C to form sintered magnets (magnet makers). The radially anisotropic sintered magnet thus obtained exhibits high magnetic performance. Furthermore, since it is advantageous in terms of price and raw material supply, it is possible to economically produce an objective lens actuator with excellent high-speed response.

Finally, the manufacturing method of the RMX type cast magnet will be explained in detail. FIG. 12 is a manufacturing process diagram of an R-M-X cast magnet. Rare earth metals (R) in the magnet composition include Y,
La, Ce, Pr, Nd, SmSE
u, Gd% Tb, DyS Ho, Er.

TmS Yb and Lu are listed as candidates, and it is possible to use one type or a combination of two or more of these. The highest magnetic properties are obtained with Pr. Candidates for the transition metal (M) include Fe, Ni, Cu, etc., and it is possible to use one type or a combination of two or more of these. IIIb
Candidates for group elements include B, A1, Ga, etc., and it is possible to use one type or a combination of two or more of these. In addition, small amounts of additive elements such as heavy rare earths Dy, 'rb, etc., Si, Co, M
o etc. are effective for improving coercive force. First, Pr17F
The raw materials were weighed so as to have a composition of e 76Cu 2B S, and melted and cast in an induction furnace to obtain a cylindrical cast ingot. At that time, columnar crystals were developed in the axial direction of the cylindrical shape using a unidirectional solidification method. Next, as shown in FIG. 13, the cast ingot 131 was placed in a mild steel capsule 132, deaerated, and sealed. This capsule is shaped to fit the cast ingot and has a mandrel hole 133 in the center.

Next, as shown in FIG. 14, the capsule containing the cast ingot was hot extruded at 850°C. 141 is a container,
142 is a press plate, 143 is a mandrel, and 144 is a die. The mandrel is inserted into the mandrel hole of the capsule. As shown in FIG. 15, during extrusion, the cast ingot is radially pressed by a mandrel or die and oriented in the radial direction. After removing the capsule, it was heat-treated at 1000°C for 24 hours to obtain a cylindrical magnet (magnet J). In addition, the composition is P r 17F e
A magnet of 76Ga2A11B6 was also produced in the same manner (magnet K). The magnet thus obtained (J,
K) is manufactured by casting and hot working, and does not go through the crushing process, so the oxygen temperature in the magnet is extremely low and it has excellent environmental resistance. It also exhibits high magnetic performance, has high mechanical strength, and has low manufacturing costs. Since it is low, it is possible to realize a high-performance and inexpensive actuator, and it can be applied to various forms of optical disk memory.

Table 1 summarizes the composition of each magnet and the number of the manufacturing process diagram. Table 2 also shows the magnetic properties of each magnet ((BH)
max), cost (raw material and manufacturing cost), and ease of thinning. In the table, the △O@ symbol in the cost section indicates that the cost becomes cheaper in that order, the O symbol in the thinning section indicates that it is extremely easy to make the wall thinner, and the ○ mark indicates that it is easy to make the wall thinner. , Δ marks indicate that thinning is possible.

Table 1 Table 2 Next, the magnetization of the magnet will be described. As shown in FIG. 16, a cylindrical magnetizing yoke 161 and a capacitor charging type pulse power source 162 were used. At this time, the applied magnetic field is 2.5 to 3 times the coercive force of the magnet, and 1. : I made it happen, the 17th
t\l (a) (b) is a developed view showing the inside of the magnetizing yoke, in which a groove 171 is provided as shown in (a). The material used is pure iron. An electric wire 172 was wound in this groove as shown by solid lines and broken lines, and a current was passed as shown by the arrow in the figure. In this example, the magnetic field in the axial direction of the magnetizing yoke is canceled, so that the magnetization is well balanced.

Tables 3-1 and 3-2 show magnet A- in Table 2, which was magnetized by the method described above for the objective lens actuator magnet of Example-1.
We have summarized the high-speed response of the actuator when its dimensions (inner diameter, outer diameter) are changed using K. In the case of the objective lens actuator, a drivable range of ±1 mm in the focusing direction (axial direction) is sufficient, so the height of the cylindrical magnet was set to 5 mm in consideration of this. If the drivable range is different for other applications, the height may be changed accordingly. O mark in the table indicates extremely good high-speed response.○
The mark indicates good, and the Δ mark indicates that high-speed operation is possible. Moreover, the - mark indicates that it is difficult to manufacture a cylindrical magnet.

Table 3-1 Table 3-2 The mechanism shown in this example and the high-performance rare earth magnet as its movable magnet (however, the magnet raw material composition, manufacturing conditions, and magnet dimensions in the above example are limited to these) By using the actuator, it is possible to improve the performance, reduce the size, and reduce the cost of the actuator. By using this as an objective lens actuator, it can be applied to various optical memory devices.

[Effects of the Invention] As described above, according to the present invention, the following advantages are produced by using a cylindrical magnet that is multipolarized in the radial direction for the movable part.

(1) There is no disconnection in the power supply line.

(2) Assembly is easy because there is no connection process for power supply lines.

(3) There is no need to worry about thermal deformation of the coil or poor adhesion.

(4) Good mass balance of moving parts.

(5) It is easy to manage the dimensions of the magnetic circuit gap.

Therefore, an inexpensive actuator with high performance and high reliability can be obtained. In particular, in the case of the structure shown in Example 1, since there is no support spring, an actuator with excellent high-speed response without high-order resonance occurring can be obtained, and assembly is further facilitated.

By using the actuator of the present invention as an objective lens actuator, it can be applied to optical memory devices such as computer memory, optical disk files, CDs, CD-ROMs, and LVDs, and can improve the performance and cost of devices. It has great effects. It can also be applied to precision positioning devices and the like in the manufacture of semiconductor integrated circuits.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the configuration of an objective lens actuator showing an embodiment of the present invention, in which (a) is a plan view;
Figure b) is a front view, and figure (c) is a sectional view. FIG. 2 is an explanatory diagram of the bearing. FIG. 3 is an explanatory diagram of the yoke ring. FIG. 4 is a magnetized button diagram of the magnet. FIG. 5 is a schematic perspective view of a side structure objective lens actuator showing one embodiment of the present invention. FIGS. 6(a), 6(b), and 6(c) are diagrams showing the structure of the magnetic circuit. FIGS. 7(a) and 7(b) are magnetization pattern diagrams of the magnet. FIG. 8 is a manufacturing process diagram of a Sm-Co resin bonded magnet. FIG. 9 is a manufacturing process diagram of a Nd-Fe-B resin bonded magnet. FIG. 10 is a manufacturing process diagram of a Nd-Fe-B magnet. FIG. 11 is a manufacturing process diagram of a sintered magnet whose basic composition is R, Fe, B, and Zr. FIG. 12 is a manufacturing process diagram of an RMX-based visiting magnet. FIG. 13 is an explanatory diagram of a cast ingot and a capsule. FIG. 14 is an explanatory diagram of hot extrusion processing of a cast ingot. FIG. 15 is an explanatory diagram of a pressurizing section for hot extrusion processing. FIG. 16 is an explanatory diagram of the magnetization method. FIGS. 17(a) and 17(b) are explanatory diagrams of the magnetizing yoke. 101... Magnet 104... Base 105... Support shaft 106.107... Yoke 109.110... Coil and above Applicant Seiko Epson Corporation Representative Patent Attorney Masayoshi Kamiyanagi 1 person 1.4. CQ 1 Figure 4 1ν3 ノν2 5L! 1 (α) (b) (C) Figure 1 (IIL) (b) 1 Figure δ $12 Figure 15)! Figure b

Claims (1)

[Scope of Claims] (1) In an actuator that is rotatable around a support shaft and can be moved linearly in the axial direction of the support shaft, (a) multipolar magnetization is applied in the radial direction, and An actuator comprising: a cylindrical magnet having a magnetized boundary in the axial direction; (b) a yoke having a magnetic pole facing the magnetized boundary; and a coil wound around the yoke. (2) The magnet contains samarium (Sm) and cobalt (
Claim 1: A Sm-Co resin-bonded magnet obtained by mixing and kneading magnetic powder obtained by pulverizing an alloy whose basic composition is Co) with a resin, and performing compression molding, injection molding, or extrusion molding.
Actuator listed. (3) Part of the Sm is replaced with neodymium (Nd), cerium (
3. The actuator according to claim 2, wherein the actuator is substituted with at least one of light rare earth metals mainly consisting of Ce) and praseodymium (Pr). (4) The magnet is made of rare earth metal (R), iron (
The R-Fe-B system is made by mixing and kneading an alloy with a basic composition of Fe) and boron (B) into a mixed state of crystal and amorphous using a melt-spun method with a resin, and then curing the mixture after pressure molding. The actuator according to claim 1, which is a resin-bonded magnet. (5) The magnet is made of an alloy whose basic composition is R, Fe, and B, which is made into a mixed state of crystals and amorphous by the melt-spun method, and then pulverized magnetic powder is placed in a cylindrical mold and subjected to hot consolidation treatment. The actuator according to claim 1, which is a Fe-B magnet. (6) The actuator according to claim 5, wherein the R-Fe-B magnet is hot-pressed in a cylindrical radial direction. (7) The magnet contains R, Fe, B, and zirconium (Z
The actuator according to claim 1, which is a sintered magnet having a basic composition of r). (8) The permanent magnet has a basic composition of R, M (where M is at least one type of transition metal) and X (where X is at least one type of IIIb group element), and is cast and hot worked. The actuator according to claim 1, which is an M-X cast magnet.