JP2002199689A - Linear oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized linear oscillator in low vibration and low noise. SOLUTION: The linear oscillator is provided with a plunger 11 freely supporting axial reciprocation, a movable part provided with an axial movement output extracting shaft 12, springs 91, 92, 93 making the movable part a spring vibration system, an electro-magnetic drive part reciprocating and driving the movable part at the resonant frequency by applying alternating current, a shield case 71 housing the electro-magnetic drive part and the movable part in the inside, and an amplitude control weight 51 reciprocated in the axial direction of the plunger 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A linear oscillator that can be used for a drive unit for controlling a machine or a drive unit such as an electric razor or an electric toothbrush converts a rotational motion of a motor into a reciprocating linear motion using a motion direction converting mechanism. Is used.

[0003]

In this case, mechanical loss and noise generated in the movement direction conversion mechanism become problems, and downsizing is also difficult.

In addition, the movable portion is caused to reciprocate in the axial direction by the electromagnetic driving force without using the movement direction converting mechanism, and at this time, the spring force of the spring member having the movable portion as a spring vibration system and the movable portion are moved. Although there is a type that reciprocates at a resonance frequency determined by the mass, there is a problem that vibration is large due to the inertial force of the movable part.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a linear oscillator that can be reduced in size with low vibration and low noise.

[0006]

In order to achieve the above object, a linear oscillator according to the present invention has the following arrangement.

According to the first aspect of the present invention, there is provided a linear oscillator comprising a movable portion capable of reciprocating movement, a case accommodating the movable portion, and an amplitude control weight movably supported by the case. The movable part and the amplitude control weight reciprocate at a resonance frequency of the linear oscillator or a frequency near the resonance frequency.

According to a second aspect of the present invention, in the linear oscillator according to the first aspect, the linear oscillator includes an electromagnetic drive unit disposed in the case for reciprocatingly driving the movable unit, and the case and the movable unit. A spring member disposed at least between the case and the amplitude control weight to form a spring vibration system, wherein the resonance frequency of the spring vibration system is at or near the resonance frequency of the linear oscillator. Frequency.

According to a third aspect of the present invention, in the linear oscillator according to the second aspect, the spring member includes a first spring disposed between the case and the movable portion, and the movable portion and the amplitude control. It is characterized by comprising a second spring disposed between the weights, and a third spring disposed between the amplitude control weight and the case.

According to a fourth aspect of the present invention, in the linear oscillator according to the second or third aspect, the electromagnetic drive unit includes a coil, and controls a reciprocating motion of the movable unit by a coil current flowing through the coil. It is characterized by the following.

According to a fifth aspect of the present invention, in the linear oscillator according to the fourth aspect, the coil is disposed on an outer periphery of the movable section, and the electromagnetic drive section is disposed on both end faces of the coil. A second yoke provided, a pair of permanent magnets magnetized in a symmetrical direction with respect to the center of the coil, and disposed on an end face of the second yoke opposite to the coil; And a first yoke disposed on the opposite side to the second yoke.

According to a sixth aspect of the present invention, in the linear oscillator according to any one of the first to fifth aspects, the movable section further includes a shaft for extracting a motion output, and the shaft includes the movable shaft. Or connected to the amplitude control weight.

According to a seventh aspect of the present invention, in the linear oscillator according to any one of the first to fifth aspects, the movable portion further includes a first axis and a second axis.
The first shaft is provided on the movable portion, the second shaft is connected to the amplitude control weight, and the first shaft or the second shaft is provided.
The motor output is extracted from at least one of the axes.

According to an eighth aspect of the present invention, in the linear oscillator according to any one of the first to seventh aspects, the movable portion and the amplitude control weight reciprocate in opposite phases.

According to a ninth aspect of the present invention, in the linear oscillator according to any one of the third to eighth aspects, a spring constant of the second spring is larger than a spring constant of the first and third springs. Features.

According to a tenth aspect of the present invention, in the linear oscillator according to any one of the first to ninth aspects, the linear oscillator further comprises a swing preventing means for preventing the amplitude control weight from swinging. I do.

According to an eleventh aspect of the present invention, in the linear oscillator according to any one of the second to tenth aspects,
The spring member is formed of a coil spring, and the mass of the amplitude control weight is larger than the mass of the movable part.

According to a twelfth aspect of the present invention, in the linear oscillator according to any one of the second to tenth aspects,
The spring member is formed of a leaf spring, and a mass of the amplitude control weight is smaller than a mass of the movable portion.

According to a thirteenth aspect of the present invention, in the linear oscillator according to any one of the second to twelfth aspects,
In the case, at least a portion facing the electromagnetic drive unit is formed of a magnetic material, and a thickness of the magnetic material at a portion facing the electromagnetic drive unit is 7% or more of an outer diameter of the permanent magnet. There is a feature.

According to a fourteenth aspect of the present invention, in the linear oscillator according to any one of the first to thirteenth aspects,
A magnetic flux increasing means for increasing a magnetic flux around the movable portion is also provided.

According to a fifteenth aspect of the present invention, in the linear oscillator according to any one of the fifth to fourteenth aspects,
The first yoke has a triangular cross section in which a side facing the case is a slope.

According to a sixteenth aspect of the present invention, in the linear oscillator according to any one of the sixth to fifteenth aspects,
The shaft is partially or entirely non-magnetic.

According to a seventeenth aspect of the present invention, in the linear oscillator according to the sixth or seventh aspect, in the shaft connected to the movable portion, a portion penetrating the movable portion is non-magnetic. And

According to an eighteenth aspect of the present invention, in the linear oscillator according to any one of the fifth to seventeenth aspects,
The yoke also includes eddy current loss reducing means for reducing eddy current loss.

According to a nineteenth aspect of the present invention, in the linear oscillator according to any one of the first to eighteenth aspects,
The movable part is further provided with eddy current loss reducing means for reducing eddy current loss.

According to a twentieth aspect, in the linear oscillator according to the nineteenth aspect, the movable portion has a slit formed in a reciprocating direction thereof, and the slit is the eddy current loss reducing means. I do.

According to a twenty-first aspect of the present invention, in the linear oscillator according to any one of the fifth to twentieth aspects,
The movable portion includes a large-diameter portion at both ends in the reciprocating direction and a small-diameter portion at a central portion, and defines a boundary surface between the large-diameter portion and the small-diameter portion with an end surface of the second yoke on the coil side. And the end face of the movable portion in the reciprocating direction substantially matches the end face of the permanent magnet on the first yoke side.

According to a twenty-second aspect of the present invention, in the linear oscillator according to any one of the fifth to twenty-first aspects,
A gap between an outer peripheral surface of the movable portion and an inner peripheral surface of the yoke is made non-uniform in a rotational direction around the axis.

According to a twenty-third aspect of the present invention, in the linear oscillator according to any one of the sixth to twenty-second aspects,
The apparatus is also provided with a rotation restricting means for restricting rotation of the shaft.

According to a twenty-fourth aspect of the present invention, in the linear oscillator according to the twenty-third aspect, the spring member is used as the rotation restricting means.

According to a twenty-fifth aspect of the present invention, in the linear oscillator according to any one of the fifth to twenty-fourth aspects,
By adjusting the relative position between the end face of the permanent magnet on the first yoke side and the end face in the reciprocating direction of the movable section according to the detent force generated in the electromagnetic drive section, the amplitude of the movable section is maximized. , Which is close to the resonance frequency of the spring vibration system.

According to a twenty-sixth aspect of the present invention, in the linear oscillator according to any one of the sixth to twenty-fifth aspects,
A bearing is provided connected to the case, the bearing having a frictional force changing unit for supporting the shaft in the axial direction and changing a frictional force generated between the shaft and the shaft in a freely increasing and decreasing manner.

According to the twenty-seventh aspect, in the linear oscillator according to any one of the sixth to twenty-fifth aspects,
A bearing provided with a frictional force changing means for supporting the shaft connected to the movable portion in the axial direction thereof and changing a frictional force generated between the movable portion and the shaft, the movable portion and the amplitude. It is characterized in that it is provided between the control weights so as to be connected to the case.

According to a twenty-eighth aspect of the present invention, in the linear oscillator according to any one of the first to twenty-seventh aspects,
The amplitude control weight is formed so that its weight can be freely increased and decreased.

According to a twenty-ninth aspect of the present invention, in the linear oscillator according to any one of the first to twenty-eighth aspects,
The amplitude control weight is provided with a through hole penetrating in the vibration direction.

According to a thirtieth aspect of the present invention, in the linear oscillator according to any one of the first to twenty-ninth aspects,
The case has a through hole penetrating in the vibration direction of the amplitude control weight.

According to a thirty-first aspect of the present invention, in the linear oscillator according to any one of the third to thirty aspects,
When the movable portion and the amplitude control weight move in opposite phases, a connection means is provided for connecting a portion of the second spring that is immovable with respect to the case and the case.

According to a thirty-second aspect of the present invention, in the linear oscillator according to any one of the first to thirty-first aspects,
A first mounting portion connected to the movable portion; and a second mounting portion connected to the amplitude control weight, wherein the first mounting portion and the second mounting portion are rotatable in symmetric directions. It is also characterized by having a link means formed so that

[0039]

FIG. 1 shows an example of an embodiment of the present invention. A movable portion includes a cylindrical plunger 11 made of a magnetic material such as an iron material and a shaft for taking out output. 12, the plunger 11 has a large diameter near both ends in the axial direction and a small diameter at the center.
The shaft 12 is fixedly penetrated, and an annular coil 61 is provided on the outer periphery of the plunger 11. Further, annular permanent magnets 81 and 82 symmetrically magnetized with respect to the coil 61 are disposed on both sides in the axial direction of the coil 61 fixed to the inner surface of the shield case 71 as a case for housing the movable portion. The permanent magnets 81 and 82 and the coil 61
Between them, annular second yokes 33 and 34 are provided,
Annular first yokes 31, 32 are arranged at positions on the opposite sides of the permanent magnets 81, 82 from the yokes 33, 34. Coil 61, permanent magnets 81, 82, yokes 31, 32, 3
An electromagnetic drive unit is constituted by 3, 34. And
A first spring 91 is provided between one end surface of the plunger 11 and the shield case 71.
A second spring 9 is provided between the other end surface of the
2, an amplitude control weight 51 and a third spring 93 are arranged in this order. Spring members (first spring 91, second spring 92, third spring
The spring 93) biases the movable part in the axial direction to form a spring vibration system. The spring members (the first spring 91, the second spring 9)
As the second and third springs 93), a coil spring which is relatively easy to obtain a large amplitude is used here, but the type of the spring is not limited to the coil spring. Hereinafter, the first spring 91, the second spring 92, and the third spring 93 are referred to as a spring 91, a spring 92, and a spring 93, respectively.

When no current is applied to the coil 61, the magnetic forces exerted on the plunger 11 by the permanent magnets 81, 82 via the yokes 31, 32, 33, 34 and the springs 91, 92, 9
The plunger 11 is stationary at the position shown in FIG. 1 where the spring force of the plunger 3 is balanced. When a one-way current is applied to the coil 61, the magnetic flux of one of the two permanent magnets 81 and 82 is weakened, so that the plunger 11 moves toward the other magnet against the spring 91. , Coil 61
When the reverse current is passed through the coil 61, the plunger moves in the reverse direction against the spring 91. Therefore, when the alternating current is passed through the coil 61, the plunger 11 reciprocates in the axial direction. Becomes possible.

Here, the plunger 11 and the shaft 12
When attention is paid to the axial movement of the movable portion having the following and the amplitude control weight 51, the linear oscillator is configured as shown in FIG. 2 due to the existence of the springs 91, 92, 93 formed by coil springs. It can be handled as a three-mass-system spring vibration system model, and the electromagnetic drive part mainly composed of the coil 61 and the shield case 71 are fixed parts, m1: movable part mass, m2: mass of the amplitude control weight 51, m3: Fixed part mass, k1: spring constant of spring 91, k2: spring constant of spring 92, k3: spring constant of spring 93, c1: damping coefficient of spring 91, c2: damping coefficient of spring 92, c3: damping of spring 93 When the coefficient is used, the equation of motion at the time of free vibration of each mass point in the spring vibration system can be expressed by equations (1), (2), and (3). Further, m1 = m2, k1 = k3, c1 = c
3, and assuming that m3 is sufficiently larger than m1 and m2, the above equation can be solved to obtain the solution of equation (4) and the solution of equation (5) (note that (Equations (4) and (5) omit the attenuation term.)

[0042]

(Equation 1)

The frequencies f1, f of the two solutions obtained here
Numeral 2 is a resonance frequency, and the vibration mode of the first-order (lower-order) natural frequency f1 in the equation (4) is based on the movable part and the amplitude control weight 5.
1 is the vibration mode in which the movable part and the amplitude control weight 51 move in the opposite phase. By applying a current having a frequency near the second-order natural frequency f2 to the coil 61, the amplitude control weight 51 performs an opposite-phase motion when the movable portion performs a reciprocating motion in the axial direction.
Can cancel the inertial force of the movable portion, and conversely, the movable portion cancels the inertial force of the amplitude control weight 51. Further, in this state, the two mass points, that is, the movable part and the inertia force of the amplitude control weight 51 try to move so as to be balanced, and the counter operation greatly cancels out the inertial force, so that the two mass points transmitted to the fixed part side are generated. (Movable part and amplitude control weight 5
The force from 1) is minimal, and therefore the vibration in the linear oscillator is minimal.

When the second-order natural frequency f2 is maintained at a constant frequency, the spring constant k2 of the spring 92 is increased, and the spring constants k1 and k3 of the springs 91 and 93 are calculated as follows.
It is also apparent from the above-mentioned equation (5) that it is necessary to make the spring constant k2 smaller than the spring constant k2. Spring 91, 9
When the spring constants k1 and k3 of 3 are small, the spring force that the amplitude control weight 51 receives from the fixed portion is reduced, and as a result, the stroke of the movable portion can be further increased.

It is desirable that the mass of the amplitude control weight 51 be larger than the mass of the movable part. In the vicinity of the second natural frequency f2, the movable part having two mass points and the amplitude control weight 51 try to move so as to balance with each other, so that the movable part having a smaller mass has a larger amplitude than the movable part having the smaller mass. This is because the vibration amplitude becomes larger than that of the control weight 51, and the stroke of the movable portion can be increased.

When moving at the lower resonance frequency, the amplitude of the movable part can be increased by the amplitude control weight 51 which moves in the same direction as the movable part. In addition, if the lower-order side and the higher-order side can be exercised by switching, it is possible to switch between vibration suppression and increase in amplitude according to the application.

FIG. 3 shows another example. Here, leaf springs 94, 95, and 96 are used as the spring members.
In this case, it is preferable that the mass of the amplitude control weight 51 be smaller than the mass of the movable part. Leaf springs 94, 95,
By using 96, not only the weight of the spring member alone can be easily reduced, but also the overall length of the linear oscillator can be easily reduced. In addition, by making the mass of the amplitude control weight 51 smaller than the mass of the movable part, it is possible to obtain a linear oscillator with extremely small vibration while reducing the overall weight.

FIG. 4 shows an example corresponding to the seventh aspect of the present invention. Here, of the two shafts provided for taking out the output, the first shaft 13 is connected to the plunger 11.
In addition, the second shaft 14 is provided on each of the amplitude control weights 51. In this case as well, the same operation as that of the linear oscillator shown in FIG. 1 can be obtained, and in the example shown in FIG. 1, only one output is provided.
Since two motor outputs having different amplitudes and different output directions are provided, it is possible to extract two motion outputs.

FIG. 5 shows an example corresponding to the sixth aspect of the present invention. In this embodiment, the output take-out shaft 12 is provided not on the plunger 11 but on the amplitude control weight 51. Also in this case, the same operation as that of the linear oscillator shown in FIG. 1 can be obtained, and the positions of the magnetic circuit portions such as the permanent magnets 81 and 82, which are usually considered to be large in mass, are compared with those shown in FIG. Since they are arranged at opposite positions, the degree of freedom in product design such as the position of the center of gravity as a whole and the distance from the power source can be increased. In addition, the weight of the amplitude control weight 51 is reduced, that is, the output stroke from the linear oscillator is increased, and both the reduction in weight and the increase in stroke can be easily achieved. Further, a member to be attached to the output take-out shaft 12 can be designed as a part of the mass of the amplitude control weight 51, and the mass of the initial amplitude control weight 51 can be reduced accordingly. Therefore, a lighter and lower-vibration linear oscillator can be obtained.

FIG. 6 shows an embodiment corresponding to the thirteenth aspect of the present invention. In this embodiment, the portion of the case 73 facing the electromagnetic drive section is made of a magnetic material, and the thickness L1 of the magnetic material is changed to the permanent magnet 81. , 82 with a thickness of at least 7% of the outer diameter L2, and by forming an air gap between the inner surface of the case 73 and the outer surfaces of the permanent magnets 81, 82 and the yokes 31, 32, 33, 34, sufficient magnetic properties can be obtained. Since a shield effect is obtained, a linear oscillator that does not affect a pacemaker or the like can be obtained.

FIG. 7 shows an example corresponding to the fourteenth and fifteenth aspects of the present invention. The yokes 35, 36 are inclined such that the surfaces of the yokes 35, 36 on the shield case 71 side are inclined.
Has a triangular cross section. With such a configuration, a distance can be provided between the yokes 35 and 36 and the shield case 71, so that the magnetic flux flowing through the shield case 71 can be reduced. Can be improved.

As shown in FIG. 8, the yokes 37, 3
The same effect can be obtained even if the outer diameter of the magnet 8 is made smaller than the outer diameter of the permanent magnets 81 and 82 so as to increase the distance from the shield case 71. At this time, the yokes 37, 38
By providing a thin magnetic layer that covers the entire surface of the permanent magnets 81 and 82, the demagnetizing effect of the permanent magnets 81 and 82 can be suppressed.

In addition, as shown in FIG.
By making the frusto-conical shape of 3,84, the magnetic flux around the plunger 11 which contributes to the thrust can be increased.

As an example corresponding to the sixteenth aspect of the present invention, the shaft 12 penetrating the plunger 11 shown in FIG. 1 is made of a non-magnetic material. As a result, an improvement in thrust can be obtained, and magnetic flux leakage through the shaft 12 can be eliminated.

As an example corresponding to the seventeenth aspect of the present invention, only the portion of the shaft 12 shown in FIG. 1 that passes through the plunger 11 is made non-magnetic. Of the axis 12,
The portion exposed to the outside of the plunger 11 is made of a metal material having high abrasion resistance, and the portion pressed into the plunger 11 is made non-magnetic so that the thrust can be improved without reducing the abrasion resistance. Can be planned.

FIG. 10 shows an example corresponding to the eighteenth aspect of the present invention. The yokes 41, 42, 43 and 44 have a laminated structure of thin plates to reduce eddy current loss. Eddy current loss is reduced, and this effect increases as the operating frequency increases.

Further, as an example corresponding to the nineteenth aspect of the present invention, the same effect can be obtained even if the plunger 11 side has a laminated structure. In addition, the use of a stacked structure also allows a material to be formed by punching, which can reduce manufacturing costs.

FIG. 11 shows an embodiment corresponding to the twentieth aspect of the present invention. In this embodiment, a plurality of slits 11a in the amplitude direction are formed in the plunger 11 in order to reduce eddy current loss. The eddy current when flowing in the axial direction of the plunger 11, which is the main magnetic flux direction, can be greatly reduced by the slit 11a. Also in this case, if the plunger 11 is made of a laminated magnetic material, the processing difficulty is reduced and the effect of reducing iron loss can be increased.

FIG. 12 shows an example corresponding to the twenty-first aspect of the present invention. When the plunger 11 having the large diameter portion at both ends in the axial direction and the small diameter portion at the center is in the neutral position, the large diameter portion is formed. The boundary surface between the portion and the small diameter portion is formed by the coils 61 of the yokes 33 and 34.
So that the axial end face of the plunger 11 can be substantially matched with the end faces of the permanent magnets 81 and 82 on the yokes 31 and 32 side. By doing so, the detent force near the neutral position becomes almost zero.
Therefore, when designing the resonance system, it is only necessary to consider the spring constant of the spring member ignoring the detent force, which facilitates the design of the resonance system.

Further, as an example corresponding to the twenty-fifth aspect of the present invention, the end faces of the permanent magnets 81, 82 on the yokes 31, 32 side and the end faces in the axial direction of the plunger 11, depending on the detent force generated in the electromagnetic drive unit. Are adjusted so that the frequency at which the amplitude of the plunger 11 becomes maximum approaches the resonance frequency of the spring vibration system. Adjustment of the relative position between the end faces of the permanent magnets 81 and 82 on the yokes 31 and 32 side and the axial end faces of the plunger 11 is performed by adjusting the yokes 31 and 3 of the permanent magnets 81 and 82 with respect to the axial end faces of the plunger 11.
This is performed by changing the position of the end face on the second side. When a detent force is exerted in a direction in which the spring 91 is weakened, the axial end faces of the plunger 11 are fixed to the permanent magnets 81 and 8.
From the end face positions on the yoke 31, 32 side of the second yoke 33,
It is adjusted so as to be shifted in the direction of the end face side on the 34 side. Conversely, when the detent force is exerted in a direction to strengthen the spring 91, the axial end faces of the plunger 11 are shifted from the end face positions of the permanent magnets 81, 82 on the yokes 31, 32 side to the yokes 31, 32 side. What is necessary is just to adjust so that it may be located.

This is because, in a spring vibration system in which the detent force is not taken into consideration, the vibration frequency of the movable part may be shifted to a frequency higher than the resonance frequency of the spring vibration system. , 82 and the axial end surface of the plunger 11 are adjusted so that the detent force generated in the electromagnetic drive unit acts in a direction to weaken the spring 91, so that the amplitude of the plunger 11 is maximized. Is reciprocated by approaching the resonance frequency of the spring vibration system.

Further, by adjusting the spring constant of the spring 91 with respect to the spring constants of the springs 92 and 93, the permanent magnets 81,
The relative position of the axial end face of the plunger 11 with respect to the end face 82 on the yoke 31, 32 side may be changed.

FIGS. 13 and 14 show an embodiment corresponding to the twenty-second aspect of the present invention, wherein the air gap between the outer peripheral surface of the plunger 11 and the inner peripheral surfaces of the yokes 31, 32 is made non-uniform in the rotation direction. I have. FIG. 14 (a) is the same as FIG.
FIG. 14B shows the positional relationship between the plunger 11 and the yoke 31 in the cross section taken along the line A in FIG. 3, and FIG.
Indicates the positional relationship between the plunger 11 and the yoke 31 in the cross section taken along line C. Thus, the plunger 11
Plunger 11 and yoke 3 depending on stroke position
Since the air gap between the plunger 1 and the air gap 1 changes in the rotational direction, a force in the rotational direction can be generated in the plunger 11 along with the axial movement of the plunger 11, and the linear motion In addition, a rotational motion can be obtained simultaneously.

FIGS. 15 and 16 correspond to the tenth aspect of the present invention.
A guide 72 is provided to prevent the swinging motion of the guide 1. As shown in FIG. 16, the guide 72 is provided with a receiving portion 72 a that supports a rail member 72 b having a square cross section in the axial direction provided on the amplitude control weight 51 so as to be slidable in the axial direction. Since the rail member 72b is slidable only in the axial direction along the receiving portion 72a, the rail member 72b
Can be prevented from swinging.

This is because when a coil spring is used as the spring member, the amplitude control weight 51 may swing without performing an ideal linear motion due to a problem of stress balance. However, by preventing the swing of the amplitude control weight 51 with the guide 72, it is possible to make the amplitude control weight 51 perform an ideal linear motion.

The swing of the amplitude control weight 51 can also be prevented by using a plurality of springs 93 disposed between the amplitude control weight 51 and the shield case 71 as shown in FIG.

Further, as shown in FIG.
By providing bearings 52 and 53 slidable with respect to the shaft 12 inside the unit 1, swinging may be prevented. When a leaf spring is used as the spring member, one end of the spring member is fixed to the amplitude control weight 51 as shown in FIG. 19 in order to prevent the leaf spring from swinging. It is also effective to form the springs 94 and 95 using leaf springs.

FIG. 20 shows an example corresponding to the twenty-third aspect of the present invention. In this embodiment, the groove 12a provided on the shaft 12 is engaged with the projection 71a provided on the shield case 71,
The rotation of the shaft 12 and the plunger 11 around the axis is restricted. With this configuration, unnecessary rotation about the axis can be suppressed.

FIG. 21 shows an example corresponding to the twenty-fourth aspect of the present invention. One end 91b of a spring 91 which is a coil spring is fixed to the shield case 71 so as not to rotate, and the other end 91a of the spring 91 is connected to the plunger 11. Also shown is a detent-fixed one. In this case, a spring 91 which is a coil spring
Not only exerts a spring force in the axial direction of the plunger 11, but also gives the plunger 11 a rotation around the axis by only a small angle with the expansion and contraction in the axial direction. A reciprocating rotation of only a small angle around can be obtained. At this time, since it also has springiness in the rotation direction,
By adjusting the resonance frequency to the resonance frequency in the rotation direction, the movable range of the rotation is also restricted, but a reliable movement can be performed.

FIG. 22 shows an example corresponding to the twenty-sixth aspect of the present invention.
2 is a bearing 87 having a frictional force changing means for supporting the shaft 2 in the reciprocating direction and freely changing the magnitude of the frictional force with the shaft 12. The bearing 87 is a bearing, and has a support at the center thereof for allowing the shaft 12 to pass therethrough.

The bearing 87 is formed so that the inner diameter of the support for supporting the shaft 12 can be changed so that the magnitude of the frictional force between the shaft 12 and the bearing 87 can be changed. Bearing 8
By increasing the inner diameter of the support portion, that is, the bearing 87 with respect to the outer diameter of the shaft 12 penetrating through the
The effect of the guide for limiting the reciprocation of the shaft only in the axial direction is reduced, but the frictional force on the shaft 12 is reduced, so that the amplitude of the shaft 12 can be increased. Conversely, by making the inner diameter of the bearing 87 smaller than the outer diameter of the shaft 12, the effect of the guide becomes very large, but the frictional force between the bearing 87 and the shaft 12 also becomes large. 8
7 is partially consumed by friction with the shaft 7 and the output taken out from the shaft 12 is reduced. Thus, by changing the inner diameter of the bearing 87, the frictional force between the shaft 12 and the bearing 87 can be changed, and the amplitude of the shaft 12 can be controlled. Incidentally, as the frictional force changing means, instead of changing the inner diameter of the bearing 87, a protrusion is provided on the inner peripheral surface of the bearing 87,
The magnitude of the frictional force between the shaft 12 and the bearing 87 may be changed by changing the size of the projection.

FIG. 23 shows an embodiment corresponding to the twenty-seventh aspect of the present invention, in which a bearing 89 for supporting the shaft 13 connected to the plunger 11 is connected to a shield case 71 using a connecting member (not shown). And between the plunger 11 and the amplitude control weight 51.

The shaft 13 is connected only to the plunger 11, is not connected to the amplitude control weight 51, and does not pass through the inside thereof. That is, the length of the shaft 13 is formed such that the shaft 13 does not contact the amplitude control weight 51 even when the plunger 11 and the amplitude control weight 51 are closest to each other during the reciprocating motion.

The bearing 89 is the same as the bearing 87,
3 is provided with a frictional force changing means for freely changing the frictional force with the shaft 3.
A spring insertion hole is provided around the supporting portion for supporting the movable member 3 in the reciprocating direction of the movable portion. The spring insertion hole is for allowing the spring 95 as the second spring to pass through the bearing 89 and bring the plunger 11 into contact with the amplitude control weight 51. That is, the bearing 89 and the spring 95 are provided in a non-connected state.

In this example, three springs 95 and three spring insertion holes for the bearing 89 are provided so that one spring 95 passes through one hole. When only two springs 95 are made to pass through one hole, the two springs 95 are twisted and entangled with each other, and the plunger 11 and the amplitude control weight 51 are stably formed. This is to prevent the inability to exercise. Also, when the two springs 95 are passed through different spring insertion holes, the two springs 95 cannot support the plunger 11 and the amplitude control weight 51 on the surface. The weight 51 cannot operate stably in the axial direction.

As described above, since the bearing 89 and the spring 95 are provided, there is no need to penetrate the shaft 13 to the amplitude control weight 51, so that the mass of the movable portion can be reduced and
2 can be buried in the hollow portion of the amplitude control weight 51 that has passed therethrough.
Can be configured with a smaller volume, and if configured with the amplitude control weight 51 having the same volume, the mass can be further increased. As described above, the weight of the movable portion can be reduced to reduce the weight of the entire linear oscillator, and the weight of the amplitude control weight 51 can increase the amplitude.

As an example corresponding to the twenty-eighth aspect of the present invention, when the amplitude control weight 51 shown in FIG. 1 is made of a magnetic material such as iron and the weight is to be increased, the amplitude control weight 51 is magnetized. By doing so, the metal powder or the like provided in the shield case 71 is attracted by its magnetic force. In this case, the magnitude of the magnetic force of the amplitude control weight 51 is adjusted so that the magnetic force of the amplitude control weight 51 does not affect the movement of the movable part.

As another example in which the weight of the amplitude control weight 51 can be freely increased and decreased, an electromagnetic coil (not shown) for generating a magnetic flux is provided on the amplitude control weight 51, and the magnetic force generated by the electromagnetic coil is used. The weight of the amplitude control weight 51 may be increased by adsorbing a metal piece provided in the shield case 71. Also in this case, the electromagnetic coil and the movable part are set apart so that the magnetic force generated by the electromagnetic coil does not affect the reciprocating motion of the movable part.

As still another example in which the weight of the amplitude control weight 51 can be freely increased and decreased, as shown in FIG. 24, the amplitude control weight 51 is formed so that the inside thereof is hollow.
A communication hole 51b for communicating the hollow portion 51a with the surface of the amplitude control weight 51 may be provided. When it is desired to increase the weight of the amplitude control weight 51 by the hollow portion 51a and the communication hole 51b, a liquid or powder having a large specific gravity may be injected into the hollow portion 51a through the communication hole 51b to close the communication hole 51b. On the contrary, when the weight is to be reduced, the hollow portion 51 is required.
It is sufficient that nothing is injected into a and a gap is left. Moreover,
If a gas having a lower specific gravity than air is injected to close the communication hole 51b, the weight can be further reduced.

FIG. 25 shows an example corresponding to the twenty-ninth aspect of the present invention, wherein the amplitude control weight 51 is provided with a through hole 51d penetrating in the reciprocating direction. Amplitude control weight 5
The air inside the linear oscillator also moves in response to the reciprocating movement of the air-conditioner 1. However, if the amplitude control weight 51 is made of a non-breathable material such as an iron material, When moving, the air inside the linear oscillator moves so as to be compressed in the gap between the amplitude control weight 51 and the shield case 71. That is, the amplitude control weight 51 receives resistance from air existing between the amplitude control weight 51 and the shield case 71 during the reciprocating motion.

Therefore, a through hole 51d penetrating in the reciprocating direction of the amplitude control weight 51 is provided in the amplitude control weight 51.
When the amplitude control weight 51 reciprocates, air existing at one end of the amplitude control weight 51 passes through the through hole 51d and moves to the other end. Thereby, the air resistance applied to the amplitude control weight 51 can be reduced, and the loss of motion can be reduced, so that the amplitude can be increased.

FIG. 26 shows an example corresponding to the thirty-first aspect of the present invention.
Are provided with through holes 71b penetrating in the reciprocating direction. As described in the example shown in FIG. 25, the amplitude control weight 51 moves by receiving resistance from the air inside the shield case 71 during the reciprocating movement. Also, like the amplitude control weight 51, the plunger 11 receives resistance from air during its reciprocating motion. In this embodiment, since the shield case 71 is provided with the through hole 71b, when the amplitude control weight 51 and the plunger 11 reciprocate, the air is passed through the through hole 71b and the linear oscillator Since the inside and outside can freely enter and exit, the air resistance applied to the amplitude control weight 51 and the plunger 11 can be reduced, the loss of the reciprocating motion of the movable part and the amplitude control weight 51 decreases, and the output amplitude increases. can do.

FIG. 27 shows an example corresponding to the thirty-first aspect of the present invention. When the movable part and the amplitude control weight 51 reciprocate in the secondary mode having the opposite phase, the spring 92 moves with respect to the shield case 71. An immovable portion and a shield case 71 are connected by an elastic body 63. This is because when the linear oscillator is subjected to an external shock when the linear oscillator is subjected to a shock from the outside when the control is performed using a feedback circuit that detects the motion state of the plunger 11 and applies an optimal voltage for the reciprocation, the reciprocation moves from the secondary mode. The mode may shift to the primary mode in which the movable part and the amplitude control weight 51 reciprocate in the same phase. Therefore, in the present embodiment, the spring 9 in the secondary mode is used.
2 fixed point 92a and shield case 71
In order to shift to the primary mode, the elastic body 63 connected to the shield case 71 becomes an obstacle to the reciprocating motion of the spring 92, so that the shift to the primary mode can be prevented.

In this case, the elastic body 63 is used as the connecting means. However, when the elastic body 63 is made of a member having no elasticity, a force for shifting from the secondary mode to the primary mode is applied to the member. If the strength is equal to or higher than the strength, the member may be damaged. Conversely, when the elastic force of the elastic body 63 is small, the reciprocation of the spring 92 cannot be stopped,
The mode may shift to the primary mode. Therefore, the elastic body 63 has a predetermined or higher elastic force, for example,
Hard rubber, plastic, thin plate-shaped metal, or the like can be used.

FIG. 28 shows an example corresponding to the thirty-second aspect of the present invention, in which a first mounting portion (hereinafter, mounting portion 85a), a second mounting portion (hereinafter, mounting portion 85b), and a connecting portion 85c are connected. A link 85 is provided as link means provided. The mounting portion 85a is attached to the plunger 11, and the mounting portion 85b
Are connected by screws to the amplitude control weight 51, and the connecting portion 85 c is connected by screws to the shield case 71.

In the link 85, the mounting portion 85a and the mounting portion 85b rotate symmetrically by the same distance about the connecting portion 85c fixedly connected to the shield case 71. By this link 85, the plunger 11 and the amplitude control weight 51 connected to the mounting portions 85a and 85b, respectively, operate in the opposite direction and at the same amplitude, and the vibration canceling action of the amplitude control weight 51 is more effective. Thus, the vibration can be more reliably reduced, and the reciprocating motion of the spring vibration system can be prevented from shifting to the primary mode due to the impact applied to the linear oscillator.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to this embodiment and can be implemented in various forms.

[0088]

As described above, according to the present invention, a linear oscillator including a reciprocally movable portion, a case for housing the movable portion, and an amplitude control weight movably supported by the case is provided. Since the movable part and the amplitude control weight reciprocate at or near the resonance frequency of the linear oscillator, the electric energy can be directly converted into linear reciprocating motion of the plunger, and the rotational motion can be linearly reciprocated. A motion conversion mechanism for converting into motion is unnecessary, and unnecessary vibration can be canceled by the vibration absorbing weight, so that it is possible to obtain a low-noise, compact and extremely low-vibration linear oscillator, It can be suitably used for a drive unit for controlling a machine, a drive unit for an electric razor or an electric toothbrush, and the like.

Further, if the movable part and the amplitude control weight reciprocate in the opposite phase, the amplitude control weight performing the movement in the opposite phase cancels the inertia force of the movable part, and conversely, the inertia force of the amplitude control weight Is canceled by the movable part, and the vibration of the linear oscillator is minimized.

Further, if the spring constant of the second spring is made larger than the spring constants of the first and third springs, the stroke of the movable part can be made larger.

Further, if a swing preventing means for preventing the swing of the amplitude control weight is also provided, the swing of the vibration absorbing weight can be suppressed, and the vibration absorbing weight can perform an ideal linear motion. Therefore, a sufficient vibration reduction effect can be obtained.

Further, when the spring member is formed by a coil spring and the mass of the amplitude control weight is larger than the mass of the movable portion, there is an effect that the stroke of the movable portion can be increased.

Further, when the spring member is formed of a leaf spring and the mass of the amplitude control weight is smaller than the mass of the movable portion, a lightweight and easy-to-use linear oscillator can be obtained.

In addition, the case is made of a magnetic material at least at the portion facing the electromagnetic drive portion, and the thickness of the magnetic material at the portion facing the electromagnetic drive portion is 7 mm of the outer diameter of the permanent magnet.
% Or more, it is possible to obtain a linear oscillator having a high magnetic efficiency and a level at which the magnetic leakage level does not affect a pacemaker or the like.

Further, when a magnetic flux increasing means for increasing the magnetic flux around the movable portion is provided, the thrust can be further improved.

Further, if the first yoke is formed so as to have a triangular cross section in which the side facing the case is inclined,
Further, the thrust can be improved.

Further, if a part or the whole of the shaft is made non-magnetic, the thrust can be improved and the magnetic flux leakage through the shaft can be eliminated.

Further, by forming the portion of the shaft connected to the movable portion that penetrates the movable portion to be non-magnetic, it is possible to improve the thrust without reducing the wear resistance.

If the yoke is provided with eddy current loss reducing means for reducing eddy current loss, eddy current loss can be reduced.

If the movable portion is provided with eddy current loss reducing means for reducing eddy current loss, eddy current loss can be reduced.

If a slit is formed in the movable portion as the eddy current loss reducing means as the eddy current loss reducing means, the eddy current when magnetic flux flows in the moving direction of the movable portion can be greatly reduced by the slit. Becomes possible.

The movable portion has a large-diameter portion at both ends in the reciprocating direction and a small-diameter portion at the center, and a boundary surface between the large-diameter portion and the small-diameter portion is formed by an end surface on the coil side of the second yoke. If the end face in the reciprocating direction of the movable part is made to substantially match the end face on the first yoke side of the permanent magnet, the detent force near the neutral position can be made substantially zero, and the resonance system Design can be performed easily.

If the gap between the outer peripheral surface of the movable portion and the inner peripheral surface of the yoke is made non-uniform in the rotation direction around the axis, a force in the rotation direction is generated according to the stroke position, and the linear motion is generated. Rotational movement can also be performed at the same time.

Further, if a rotation restricting means for restricting rotation of the shaft is provided, unnecessary rotation of the shaft can be suppressed.

Further, if the spring member is a rotation restricting means,
The rotation can be regulated without requiring a separate member.

Also, the relative position between the end face of the permanent magnet on the first yoke side and the end face in the reciprocating direction of the movable section is adjusted according to the detent force generated in the electromagnetic drive section, so that the amplitude of the movable section is maximized. If the frequency is set close to the resonance frequency of the spring vibration system, the operation of the amplitude control weight can be improved and the vibration can be reduced.

Further, the amplitude can be controlled by connecting the bearing to the case, which supports the shaft in the axial direction and is provided with a friction force changing means for freely changing the friction force generated between the shaft and the shaft. Becomes

A bearing provided with a frictional force changing means for supporting a shaft connected to the movable portion in the axial direction thereof and changing the frictional force generated between the shaft and the shaft connected to the movable portion so as to be able to freely increase and decrease. If provided between the movable part and the amplitude control weight by connecting to the case, there is no need to penetrate the shaft to the amplitude control weight, so the mass of the movable part can be reduced, vibration can be reduced, and the amplitude control weight can be reduced. Since it is not necessary to provide a hollow portion through which the shaft passes, the weight can be made heavy with a small volume, and the amplitude can be increased.

If the amplitude control weight is formed so that its weight can be freely increased and decreased, the resonance characteristics can be made variable and the amplitude can be controlled.

Further, if the amplitude control weight is provided with a through-hole penetrating in the vibration direction, the air resistance during the reciprocating motion can be reduced, and the amplitude can be increased.

If a through-hole is provided in the case in the vibration direction of the amplitude control weight, air resistance can be reduced and the amplitude can be increased when the movable part and the amplitude control weight reciprocate. It becomes possible.

Further, when the movable portion and the amplitude control weight move in opposite phases, the portion becomes immovable with respect to the case of the second spring.
If a connecting means for connecting the case and the case is also provided, it is possible to prevent the movable portion and the amplitude control weight from operating in the same phase.

Further, the first mounting portion is connected to the movable portion, the second mounting portion is connected to the amplitude control weight, and the first mounting portion and the second mounting portion are formed so as to be rotatable in symmetric directions. If the link means is provided, the movable section and the amplitude control weight can always be operated in opposite phases, and it is possible to prevent the movable section and the amplitude control weight from operating in the same phase.

[Brief description of the drawings]

FIG. 1 is a sectional view of an example of an embodiment of the present invention.

FIG. 2 is a model diagram of the above.

[Equation 1] Equation of motion of the same spring vibration system model

FIG. 3 is a sectional view of another example of the above.

FIG. 4 is a sectional view of another example of the above.

FIG. 5 is a sectional view of another example of the above.

FIG. 6 is a sectional view of another example of the above.

FIG. 7 is a sectional view of another example of the above.

FIG. 8 is a sectional view of another example of the above.

FIG. 9 is a sectional view of another example of the above.

FIG. 10 is a sectional view of another example of the above.

FIG. 11 is a perspective view of a plunger in another example of the above.

FIG. 12 is a sectional view of another example of the above.

FIG. 13 is a cross-sectional view of another example of the above.

14A is a diagram showing a positional relationship between a plunger and a yoke in a cross-sectional view taken along the line A in FIG.
(C) is a diagram showing a positional relationship between the plunger and the yoke in the sectional view taken along the line C of the above.

FIG. 15 is a sectional view of another example of the above.

FIG. 16 is a partial sectional view showing a supporting relationship between the amplitude control weight and the case according to the first embodiment;

FIG. 17 is another sectional view of the above.

FIG. 18 is a sectional view of another example of the above.

FIG. 19 is a sectional view of another example of the above.

20 shows another example of the above, wherein (a) is a cross-sectional view and (b) is a partial end view. FIG.

FIG. 21 is a sectional view of another example of the above.

FIG. 22 is a sectional view of another example of the above.

FIG. 23 is a cross-sectional view of another example of the above.

FIG. 24 is a perspective view of an amplitude control weight in another example of the above.

FIG. 25 is a sectional view of another example of the above.

FIG. 26 is a sectional view of another example of the above.

FIG. 27 is a sectional view of another example of the above.

FIG. 28 is a sectional view of another example of the above.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 plunger 11 a slit 12 shaft 31 yoke 32 yoke 33 yoke 34 yoke 51 amplitude control weight 51 a hollow portion 51 b communication hole 51 d through hole 52 bearing 53 bearing 61 coil 63 elastic body 71 shield case 71 b through hole 81 permanent magnet 82 permanent magnet 85 Link 85a Mounting section 85b Mounting section 87 Bearing 89 Bearing 91 Spring 92 Spring 92a Fixed point 93 Spring 94 Leaf spring 95 Leaf spring 96 Leaf spring

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Katsuhiro Hirata 1048 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Inventor Yuya Hasegawa 1048 Kadoma Kadoma Kadoma City Osaka Prefecture 72) Inventor Eiichi Yabuuchi 1048 Kadoma, Kadoma, Osaka Pref., Matsushita Electric Works, Ltd. (72) Inventor Hiromiki Inoue 1048 Kadoma, Oji, Kadoma, Osaka Pref. Matsushita Electric Works, Ltd. 1048, Kazuma, Kamon, Fumonma-shi F-term (reference), Matsushita Electric Works, Ltd.

Claims (32)

[Claims] 1. A linear oscillator comprising: a reciprocally movable movable portion; a case accommodating the movable portion; and an amplitude control weight movably supported by the case. A linear oscillator, wherein the control weight reciprocates at a resonance frequency of the linear oscillator or a frequency near the resonance frequency. 2. An electromagnetic drive unit disposed in the case and reciprocatingly driving the movable unit, and a spring disposed at least between the case and the movable unit and between the case and the amplitude control weight. The linear oscillator according to claim 1, further comprising a spring member forming a vibration system, wherein a resonance frequency of the spring vibration system is a resonance frequency of the linear oscillator or a frequency near the resonance frequency. A first spring disposed between the case and the movable portion; a second spring disposed between the movable portion and the amplitude control weight; The linear oscillator according to claim 2, further comprising: a third spring disposed between the control weight and the case. 4. The linear oscillator according to claim 2, wherein the electromagnetic drive unit includes a coil, and controls a reciprocating motion of the movable unit by a coil current flowing through the coil. 5. The coil is disposed on an outer periphery of the movable portion, and the electromagnetic driving portion is disposed on a second yoke disposed on both end surfaces of the coil and a center of the coil. A pair of permanent magnets that are magnetized in a symmetrical direction and are disposed on an end face of the second yoke opposite to the coil, and a pair of permanent magnets disposed on the opposite side of the permanent magnet from the second yoke; 5. The linear oscillator according to claim 4, comprising: a first yoke. 6. The moving part according to claim 1, further comprising a shaft for extracting a motion output, wherein the shaft is connected to the moving part or the amplitude control weight. Item 6. The linear oscillator according to any one of Items 5. 7. The movable section also includes a first axis and a second axis, and the first axis is connected to the movable section, and the second axis is connected to the amplitude control weight. The linear oscillator according to any one of claims 1 to 5, wherein a motion output is taken out from at least one of the first axis and the second axis. 8. The apparatus according to claim 1, wherein the movable section and the amplitude control weight reciprocate in opposite phases.
The linear oscillator according to any one of the above. 9. The linear oscillator according to claim 3, wherein a spring constant of the second spring is larger than a spring constant of the first and third springs. 10. The linear oscillator according to claim 1, further comprising a swing preventing unit for preventing the amplitude control weight from swinging. 11. The apparatus according to claim 2, wherein the spring member is formed of a coil spring, and the mass of the amplitude control weight is larger than the mass of the movable part. The described linear oscillator. 12. The apparatus according to claim 2, wherein the spring member is formed of a leaf spring, and a mass of the amplitude control weight is smaller than a mass of the movable portion.
0. The linear oscillator according to any one of 0. 13. The case, wherein at least a portion facing the electromagnetic driving portion is formed of a magnetic material, and a thickness of the magnetic material at a portion facing the electromagnetic driving portion is an outer diameter of the permanent magnet. 13. The linear oscillator according to claim 2, wherein the linear oscillator is at least 7%. 14. The linear oscillator according to claim 1, further comprising magnetic flux increasing means for increasing magnetic flux around the movable portion. 15. The linear oscillator according to claim 5, wherein the first yoke has a triangular cross section in which a side facing the case is a slope. 16. The linear oscillator according to claim 6, wherein the shaft is partially or entirely non-magnetic. 17. The linear oscillator according to claim 6, wherein a portion of the shaft connected to the movable portion penetrating the movable portion is non-magnetic. 18. The linear oscillator according to claim 5, wherein said yoke further includes an eddy current loss reducing means for reducing an eddy current loss. 19. The linear oscillator according to claim 1, wherein the movable section further includes an eddy current loss reducing means for reducing eddy current loss. 20. The linear oscillator according to claim 19, wherein the movable portion has a slit formed in a reciprocating direction thereof, and the slit is the eddy current loss reducing means. 21. The movable part has a large diameter part at both ends in the reciprocating direction and a small diameter part at a center part, and a boundary surface between the large diameter part and the small diameter part is provided on the second yoke. 21. The end face of the movable part in the reciprocating direction substantially coincides with the end face on the coil side, and the end face on the first yoke side of the permanent magnet substantially coincides with the end face on the first yoke side.
The linear oscillator according to any one of the above. 22. The apparatus according to claim 5, wherein a gap between an outer peripheral surface of the movable portion and an inner peripheral surface of the yoke is non-uniform in a rotation direction about the axis. The described linear oscillator. 23. The apparatus according to claim 6, further comprising a rotation restricting means for restricting rotation of the shaft.
3. The linear oscillator according to any one of 2. 24. The linear oscillator according to claim 23, wherein said spring member is used as said rotation restricting means. 25. The movable position of the permanent magnet is adjusted by adjusting a relative position between an end surface of the permanent magnet on the first yoke side and an end surface of the movable portion in a reciprocating direction according to a detent force generated in the electromagnetic drive portion. The linear oscillator according to any one of claims 5 to 24, wherein a frequency at which the amplitude of the portion becomes maximum is close to a resonance frequency of the spring vibration system. 26. A bearing, which supports the shaft in the axial direction and includes a frictional force changing means for changing a frictional force generated between the shaft and the shaft so as to be able to increase and decrease, is provided to be connected to the case. The linear oscillator according to any one of claims 6 to 25, characterized in that: 27. A bearing, comprising: a bearing for supporting the shaft connected to the movable portion in an axial direction thereof, and a frictional force changing means for changing a frictional force generated between the shaft and the supported shaft in a freely increasing and decreasing manner. 26. The linear oscillator according to claim 6, wherein the linear oscillator is provided between the movable portion and the amplitude control weight so as to be connected to the case. 28. The amplitude control weight is formed so as to be capable of increasing and decreasing its weight.
28. The linear oscillator according to claim 27. 29. The linear oscillator according to claim 1, wherein the amplitude control weight is provided with a through-hole penetrating in the vibration direction. 30. The linear oscillator according to claim 1, wherein the case has a through hole penetrating in a vibration direction of the amplitude control weight. 31. The apparatus according to claim 31, further comprising a connection means for connecting the case and the portion of the second spring which is immovable with respect to the case when the movable portion and the amplitude control weight move in opposite phases. 31. The linear oscillator according to claim 3, wherein: 32. A semiconductor device, comprising: a first mounting portion connected to the movable portion; and a second mounting portion connected to the amplitude control weight, wherein the first mounting portion and the second mounting portion are symmetrical. 32. The linear oscillator according to claim 1, further comprising link means formed so as to be rotatable in a direction.