JP3475949B2 - Linear oscillator - Google Patents

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 As a linear oscillator that can be used for a drive unit for machine control, a drive unit for an electric razor, an electric toothbrush, etc., a rotary motion of a motor is converted into a reciprocating linear motion by using a motion direction conversion mechanism. Is used.

[0003]

In this case, the mechanical loss and noise generated in the movement direction converting mechanism poses a problem, and it is difficult to reduce the size.

In addition, the movable portion is caused to reciprocate in the axial direction by an electromagnetic driving force without using the movement direction conversion mechanism, and at this time, the spring force of the spring member and the movable portion which make the movable portion a spring vibration system. There is also one that reciprocates at a resonance frequency determined by the mass, but this has 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 which has low vibration and low noise and can be miniaturized.

[0006]

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

According to the invention of claim 1, a reciprocating movable part, a case accommodating the movable part, and an amplitude control weight capable of moving separately from the movable part movably supported by the case, In the linear oscillator, the movable part and the amplitude control weight reciprocate at a resonance frequency of the linear oscillator or at a frequency in the vicinity thereof.

According to a second aspect of the present invention, in the linear oscillator according to the first aspect, the linear oscillator is arranged in the case, and the electromagnetic drive section reciprocally drives the movable section; the case and the movable section. And a spring member disposed at least between the case and the amplitude control weight to form a spring vibration system, and the resonance frequency of the spring vibration system is at or near the resonance frequency of the linear oscillator. It is characterized by the frequency of.

According to a third aspect of the 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, the movable portion and the amplitude control. It is characterized by comprising a second spring arranged between the weights and a third spring arranged 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 section includes a coil, and the coil current flowing through the coil controls the reciprocating motion of the movable section. It is characterized by

According to a fifth aspect of the present invention, in the linear oscillator according to the fourth aspect, the coil is arranged on the outer circumference of the movable part, and the electromagnetic drive parts are arranged on both end faces of the coil, respectively. A second yoke that is provided, a pair of permanent magnets that are magnetized in a symmetrical direction with respect to the center of the coil and that are disposed on an end surface of the second yoke that is opposite to the coil, and A first yoke arranged on the opposite side of 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 portion also has a shaft for taking out a motion output, and the shaft is the movable member. It is characterized in that it is provided so as to be connected to the section or the amplitude control weight.

According to a seventh aspect of the invention, in the linear oscillator according to any one of the first to fifth aspects, the movable portion also has a first shaft and a second shaft, and
The first shaft is connected to the movable portion, the second shaft is connected to the amplitude control weight, and the first shaft or the second shaft is provided.
It is characterized in that the motion output is taken out from at least one of the axes.

According to an eighth aspect of the invention, in the linear oscillator according to any 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 invention, in the linear oscillator according to any one of the third to eighth aspects, the spring constant of the second spring is larger than the spring constants of the first and third springs. Characterize.

[0016]

[0017]

[0018]

[0019] In the present invention of claim 1 0, in the linear oscillator according to any one of claims 5 to 9,
At least a portion of the case facing the electromagnetic drive unit is formed of a magnetic material, and a thickness of the magnetic material of the portion facing the electromagnetic drive unit is 7% or more of an outer diameter of the permanent magnet. It is characterized by being.

[0020] In the present invention of claim 1 1, in the linear oscillator according to any one of claims 5 to 1 0, characterized in that it also comprises a magnetic flux increasing means for increasing the magnetic flux around the movable portion.

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

According to a twelfth aspect of the present invention, in the linear oscillator according to any one of the fifth to eleventh aspects, the movable portion has large diameter portions at both ends in the reciprocating direction.
The central portion is provided with a small diameter portion, and the boundary surface between the large diameter portion and the small diameter portion is made to substantially coincide with the end surface of the second yoke on the coil side, and the end face of the movable portion in the reciprocating direction is made permanent. It is characterized in that it is substantially aligned with the end surface of the magnet on the side of the first yoke.

[0028]

[0029] In the invention of claim 1 3, in the linear oscillator according to any one of claims 6 to 1 2, characterized in that it also includes a rotation restricting means for restricting the rotation of said shaft.

[0030] In the invention of claim 1 4, in the linear oscillator according to claim 1 3, characterized in that said spring member is set to the rotation restricting means.

[0031] In the invention of claim 1 5, in the linear oscillator according to any one of claims 5 to 1 4, in accordance with the detent force generated in the electromagnetic drive unit,
By adjusting the relative position between the end surface of the permanent magnet on the side of the first yoke and the end surface of the movable portion in the reciprocating direction, the frequency at which the amplitude of the movable portion becomes maximum is set to the resonance frequency of the spring vibration system. It is characterized by being close to each other.

[0032]

[0033]

[0034]

[0035]

[0036]

According to a sixteenth aspect of the invention, in the linear oscillator according to any one of the third to fifteenth aspects, the case of the second spring when the movable portion and the amplitude control weight move in opposite phases. On the other hand, it is characterized in that it is also provided with a connecting means for connecting the stationary portion and the case.

According to a seventeenth aspect of the present invention, in the linear oscillator according to any one of the first to sixteenth aspects, a first attachment portion connected to the movable portion and a second attachment portion connected to the amplitude control weight are provided. And a link means formed so that the first mounting portion and the second mounting portion are rotatable in a symmetrical direction. Contract
In the invention of claim 18, either claim 1 or claim 8
In the linear oscillator according to Crab, in the case
An electromagnetic drive unit that is disposed and that reciprocally drives the movable unit;
Between the case and the movable part, and between the case and the
Formed at least between the amplitude control weights to form a spring vibration system.
And a spring member to be formed.

[0039]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of an embodiment of the present invention, in which a movable part is a cylindrical blanker 11 made of a magnetic material such as an iron material, and an output extracting shaft. 12, the blanker 11 has a large diameter in the vicinity of both axial ends thereof and a small diameter in the central portion thereof.
The shaft 12 is fixed through, and an annular coil 61 is arranged on the outer periphery of the blanker 11. Further, annular permanent magnets 81 and 82 that are symmetrically magnetized with respect to the coil 61 are disposed on both axial sides of the coil 61 that is fixed to the inner surface of a shield case 71 that is a case that houses the movable portion. The permanent magnets 81 and 82 and the coil 61.
An annular second yoke 33, 34 is disposed between
Annular first yokes 31 and 32 are arranged at positions opposite to the yokes 33 and 34 of the permanent magnets 81 and 82. 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 arranged between one end surface of the blanker 11 and the shield case 71.
The second spring 9 is provided between the other end surface and the shield case 71.
2, the amplitude control weight 51, and the third spring 93 are arranged in this order. Spring member (first spring 91, second spring 92, third spring
The spring 93) negatively biases the movable portion in the axial direction to form a spring vibration system. The spring member (the first spring 91, the second spring 9
As the second and third springs 93), coil springs which are relatively easy to obtain a large amplitude are used here, but the types of springs are not limited to coil springs. Hereinafter, the first spring 91, the second spring 92, and the third spring 93 will be referred to as the spring 91, the spring 92, and the spring 93, respectively.

When no current is applied to the coil 61, the magnetic force exerted on the blanker 11 by the permanent magnets 81, 82 via the yokes 31, 32, 33, 34 and the springs 91, 92, 9 are provided.
The blanker 11 is stationary in the position shown in FIG. Then, when a unidirectional 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 blanker 11 moves to the other magnet side against the spring 91. , Coil 61
When a reverse current is applied to the coil 91, it moves in the opposite direction against the spring 91. Therefore, by supplying an alternating current to the coil 61, the blanker 11 reciprocates in the axial direction, and the reciprocal motion is controlled by the coil current. Is possible.

Here, the blanker 11 and the shaft 12
When attention is paid to the movement in the axial direction of the amplitude control weight 51 and the movable part provided with, due to the existence of the springs 91, 92, 93 which are coil springs, this linear oscillator has a structure as shown in FIG. It can be treated as a three-mass system spring vibration system model, and the electromagnetic drive section mainly composed of the coil 61 and the shield case 71 are fixed sections, and m1: movable part mass, m2: amplitude control weight 51 mass, 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 during free vibration of each mass point in the spring vibration system can be expressed by equations (1), (2), and (3), and m1 = m2, k1 = k3, c1 = c
3, and m3 is assumed to be sufficiently larger than m1 and m2, the solution of the equation (4) and the solution of the equation (5) can be obtained by solving the above equation (note that (The damping term is omitted in the equations (4) and (5).)

[0042]

[Formula 1]

The frequencies f1 and f of the two solutions obtained here
2 is the resonance frequency, and the vibration mode of the first-order (low-order side) natural frequency f1 of the equation (4) is the movable part and the amplitude control weight 5
1 and the vibration mode of the natural frequency f2 of the second order (higher order side) of the formula (5) are the vibration modes in which the movable part and the amplitude control weight 51 move in opposite phases. By applying a current having a frequency in the vicinity of the second natural frequency f2 to the coil 61, when the movable part is caused to reciprocate in the axial direction, the amplitude control weight 51 which performs the opposite phase motion.
Can cancel the inertial force of the movable part, and conversely, the movable part cancels the inertial force of the amplitude control weight 51. Furthermore, in this state, two mass points try to move so that the inertial force of the movable part and the inertial force of the amplitude control weight 51 are balanced, and the counteracting effect of the inertial forces due to the counter operation is great, and therefore the two mass points transmitted to the fixed part side. (Movable part and amplitude control weight 5
The force from 1) is minimal, and therefore the vibration in the linear oscillator is minimal.

By the way, in order to maintain the second-order natural frequency f2 at a constant frequency, the spring constant k2 of the spring 92 is set large, and the spring constants k1 and k3 of the springs 91 and 93 are set to
It is clear from the above-mentioned formula (5) that the spring constant k2 of the spring 92 needs to be smaller. Springs 91, 9
If the spring constants k1 and k3 of 3 are small, the spring force that the amplitude control weight 51 receives from the fixed portion becomes small, and as a result, the stroke of the movable portion can be made larger.

Further, it is desirable to make the mass of the amplitude control weight 51 larger than that of the movable part. In the vicinity of the second-order natural frequency f2, the movable part, which is two mass points, and the inertial force of the amplitude control weight 51 try to move in a balanced manner, so that the movable part having a smaller mass has a larger amplitude. 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.

It should be noted that 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 when it is moved at the resonance frequency on the low order side. In addition, if the low-order side and the high-order side can be switched and exercised, it is possible to switch between damping 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, the mass of the amplitude control weight 51 is preferably 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 total length of the linear oscillator can be shortened easily. 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 invention of claim 7, in which the first shaft 13 of the two shafts provided for output extraction is replaced by the blanker 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, but in this example, two axes are used.
Since two motion outputs having different amplitudes and output directions are provided, it is possible to extract two motion outputs.

FIG. 5 shows an example corresponding to the invention of claim 6, in which the output take-out shaft 12 is provided not on the blanker 11 but on the amplitude control weight 51. In this case as well, the same operation as that of the linear oscillator shown in FIG. 1 can be obtained, and the positions of the magnetic circuit parts such as the permanent magnets 81 and 82, which are usually considered to have a large mass, are compared with those shown in FIG. Since they are arranged at opposite positions, it is possible to increase 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. Further, the weight of the amplitude control weight 51 can be reduced, that is, the output stroke from the linear oscillator can be increased, and it is possible to easily achieve both reduction in weight and increase in stroke. Further, it is also possible to design a member to be attached to the output take-out shaft 12 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, it is possible to obtain a lighter weight, low-vibration linear oscillator.

[0050] Figure 6 shows an example corresponding to the invention of claim 1 0, wherein constitutes a portion facing the electromagnetic drive portion of the case 73 of a magnetic material, a permanent magnet thickness width L1 of the magnetic material The thickness is 7% or more of the outer diameter L2 of 81, 82,
In addition, 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, a sufficient magnetic shield effect can be obtained. It is possible to obtain a linear oscillator that does not affect even.

[0051] Figure 7 shows an example corresponding to the invention of claim 1 1, which faces the shield case 71 side of the yoke 35, 36 has a triangular cross-sectional shape of the yoke 35 so that the inclined surface Is. With this configuration,
Since a distance can be provided between the yokes 35 and 36 and the shield case 71, the magnetic flux flowing in the shield case 71 can be reduced.
The driving thrust of can be improved.

Further, as shown in FIG.
Even if the outer diameter of 8 is made smaller than the outer diameters of the permanent magnets 81 and 82 to keep the distance from the shield case 71, the same effect can be obtained. At this time, the yokes 37, 38
By providing a thin magnetic layer that covers the entire surfaces of the permanent magnets 81 and 82, the demagnetizing effect of the permanent magnets 81 and 82 can be suppressed.

In addition to this, as shown in FIG.
By making the cones 3 and 84 have a truncated cone shape, it is possible to increase the magnetic flux around the blanker 11 that contributes to the thrust.

As an example of another embodiment , FIG.
A non-magnetic material is used for the shaft 12 passing through the blanker 11 shown in FIG. As a result, the thrust can be improved and the magnetic flux leakage through the shaft 12 can be eliminated.

As an example of another embodiment , FIG.
Of the shaft 12 shown in (1), only the portion penetrating the blanker 11 is made non-magnetic. A portion of the shaft 12 exposed to the outside of the blanker 11 is made of a metal material having high wear resistance, and the portion press-fitted into the blanker 11 is made non-magnetic to reduce wear resistance. Without increasing the thrust.

FIG. 10 shows an example of another embodiment , in which the yokes 41, 42, 43 and 44 have a laminated structure of thin plates to reduce the eddy current loss. The eddy current loss decreases, and this effect increases as the operating frequency increases.

Further, as another example of the embodiment, the same effect can be obtained even if the blanker 11 side has a laminated structure. In addition, the laminated structure also allows the material to be formed by punching, and the manufacturing cost can be reduced.

FIG. 11 shows an example of another embodiment . In order to reduce the eddy current loss, a plurality of slits 11 a in the amplitude direction are formed in the blanker 11 here. The eddy current when flowing in the axial direction of the blanker 11, which is the main magnetic flux direction, can be greatly reduced by the slit 11a. Even in this case, if the blanker 11 is formed by stacking magnetic materials, the difficulty of processing can be reduced and the effect of reducing iron loss can be increased.

FIG. 12 shows an example corresponding to the invention of claim 12 , and when the blanker 11 having the large diameter portion at both ends in the axial direction and the small diameter portion at the central portion is at the neutral position, The boundary surface between the small portion and the small diameter portion to the coil 6 of the yokes 33 and 34
The end face of the blanker 11 in the axial direction can be made to substantially coincide with the end face on the first side, and the end faces of the permanent magnets 81, 82 on the yoke 31, 32 side can be made to substantially coincide. By doing so, the detent force near the neutral position can be made almost zero. Therefore, when designing the resonance system, it is possible to ignore the detent force and consider only the spring constant of the spring member. Therefore, the design of the resonance system becomes easy.

In addition, as an example corresponding to the invention of claim 15 , according to the detent force generated in the electromagnetic drive unit, the end faces of the permanent magnets 81 and 82 on the side of the yokes 31 and 32 and the axial end face of the blanker 11 are arranged. Adjust the position relative to
The frequency at which the amplitude of the blanker 11 is maximized is close to the resonance frequency of the spring vibration system. The relative positions of the end surfaces of the permanent magnets 81, 82 on the side of the yokes 31, 32 and the axial end surface of the blanker 11 are adjusted by adjusting the yokes 31, 24 of the permanent magnets 81, 82 relative to the axial end surface of the blanker 11.
This is done by changing the position of the end face on the 32 side,
When the detent force is exerted in the direction in which the spring 91 is weakened, the axial end surface of the blanker 11 is fixed to the permanent magnets 81, 8
2 from the end surface position on the side of the yokes 31 and 32 to the yoke 33,
It is adjusted so as to be displaced in the direction of the end surface on the 34 side. On the contrary, when the detent force is exerted in the direction of strengthening the spring 91, the axial end surface of the blanker 11 is shifted from the end surface positions of the permanent magnets 81, 82 on the yoke 31, 32 side to the yoke 31, 32 side. Adjust it so that it is positioned.

In a spring vibration system in which the detent force is not taken into consideration, the vibration frequency of the movable portion may deviate to a frequency higher than the resonance frequency of the spring vibration system. , 82 and the axial end surface of the blanker 11 are adjusted so that the detent force generated in the electromagnetic drive portion works in a direction to weaken the spring 91, so that the amplitude of the blanker 11 is maximized. The reciprocating motion is performed by bringing the frequency that is close to 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 blanker 11 with respect to the end faces of the yoke 31 and 32 side of 82 may be changed.

13 and 14 show an example of another embodiment, in which the outer peripheral surface of the blanker 11 and the yoke 3 are shown.
The air gaps between the inner peripheral surfaces of 1, 32 are non-uniform in the rotational direction. It should be noted that FIG.
The positional relationship between the blanker 11 and the yoke 31 in the line cross section, FIG. 14B shows the positional relationship between the blanker 11 and the yoke 31 in the B line cross section, and FIG. 14C shows the blanker 11 in the C line cross section. The positional relationship between the yoke 31 and the yoke 31 is shown. As described above, the air gap between the blanker 11 and the yoke 31 is changed in the rotational direction depending on the stroke position of the blanker 11, so that the blanker 11 moves along with the axial movement of the blanker 11. It is also possible to generate a force in the direction of rotation, and it is possible to obtain rotational movement as well as linear movement at the same time.

FIG. 15 and FIG.Example of another embodiment
Then, the swing of the amplitude control weight 51 on the inner surface of the shield case 71
A guide 72 is provided to prevent this. As shown in FIG.
This guide 72 is provided in the axial direction provided on the amplitude control weight 51.
A rail member 72b with a rectangular cross section can be slid in the axial direction.
A receiving portion 72a for supporting the above is provided. Les
The ruler member 72b is limited only in the axial direction along the receiving portion 72a.
Since the rail member 72b is fixed and can be slid,
It is possible to prevent the swinging of the amplitude control weight 51 that is generated.

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

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

Further, as shown in FIG. 18, the amplitude control weight 5
Swing prevention may be achieved by providing bearings 52 and 53 that are slidable with respect to the shaft 12 inside 1. When a leaf spring is used as the spring member, one end of the spring member should be 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 to be a leaf spring.

[0068] Figure 20 shows an example corresponding to the invention of claim 1 3, wherein the at engaging with the projection 71a provided with a groove 12a provided in the shaft 12 to the shield case 71, the shaft 12 and The rotation around the axis of the blanker 11 is restricted. With this configuration, unnecessary rotation about the axis can be suppressed.

FIG. 21 shows an example corresponding to the invention of claim 14 in which one end 91b of a spring 91 which is a coil spring.
Is fixed to the shield case 71 in a non-rotating manner, and the other end 91a of the spring 91 is also fixed to the blanker 11 in a non-rotating manner. In this case, the spring 9 which is a coil spring
1 not only exerts a spring force in the axial direction of the blanker 11, but also gives the blanker 11 a rotation about an axis of only a small angle in accordance with the expansion and contraction in the axial direction. It is also possible to obtain reciprocal rotation about only a small angle around the axis. At this time, since the spring has elasticity in the rotation direction as well, by adjusting the resonance frequency in the rotation direction, the movable range of the rotation is restricted, but reliable movement can be performed.

FIG. 22 shows an example of another embodiment, which is connected to a shield case 71 to support the shaft 12 in its reciprocating direction and to freely control the magnitude of frictional force with the shaft 12. Bearing 87 having frictional force changing means for changing
Is. The bearing 87 is a bearing, and is provided with a support portion for allowing the shaft 12 to pass therethrough at the center thereof.

In order to change the magnitude of the frictional force between the shaft 12 and the bearing 87, the bearing 87 is formed so that the inner diameter of the supporting portion for supporting the shaft 12 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 passing through the shaft 12,
Although the effect of the guide that limits the reciprocating movement of the shaft 12 only in the axial direction becomes small, the frictional force to the shaft 12 becomes small, so that the amplitude of the shaft 12 can be taken out large. 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 since the frictional force between the bearing 87 and the shaft 12 also becomes large, the shaft 12 and the bearing 12 become large. 8
It is partially consumed by the friction with 7, and the output taken out from the shaft 12 becomes small. Thus, by changing the inner diameter of the bearing 87, it is possible to change the frictional force between the shaft 12 and the bearing 87 and control the amplitude of the shaft 12. As the frictional force changing means, a protrusion is provided on the inner peripheral surface of the bearing 87 instead of changing the inner diameter 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 protrusion.

FIG. 23 shows an example of another embodiment, in which the bearing 89 that supports the shaft 13 connected to the blanker 11 is supported by the shield case 71 using a connecting member (not shown). In addition, it is provided between the blanker 11 and the amplitude control weight 51.

The shaft 13 is connected only to the blanker 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 blanker 11 and the amplitude control weight 51 come closest to each other during the reciprocating motion.

The bearing 89 is similar to the bearing 87 in the shaft 1
3 is provided with a frictional force changing means for changing the frictional force with the shaft 3 freely. In addition to this, the bearing 89 includes the shaft 1
A spring insertion hole that penetrates in the reciprocating direction of the movable portion is provided around the support portion that supports 3. The spring insertion hole is for allowing the spring 95, which is the second spring, to pass through the bearing 89 and bring the blanker 11 and the amplitude control weight 51 into contact with each other. That is, the bearing 89 and the spring 95 are provided in a non-connected manner.

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

Since the bearing 89 and the spring 95 are provided as described above, it is not necessary to penetrate the shaft 13 to the amplitude control weight 51, and the mass of the movable portion can be reduced, and at the same time, the shaft 1 can be reduced.
Since it is possible to fill the hollow portion of the amplitude control weight 51 that has passed through 2, the amplitude control weight 51 having the same mass can be filled.
Can be configured with a smaller volume, and if configured with the amplitude control weights 51 of the same volume, the mass can be increased. As described above, by reducing the weight of the movable portion, the weight of the entire linear oscillator can be reduced, and by increasing the weight of the amplitude control weight 51, the amplitude can be increased.

As an example of another embodiment, the amplitude control weight 51 shown in FIG. 1 is made of a magnetic material such as iron,
When it is desired to increase the weight, the amplitude control weight 51 is magnetized to attract the metal powder or the like provided in the shield case 71 by its magnetic force.
In this case, the strength of the magnetic force of the amplitude control weight 51 is adjusted so that the movement of the movable part is not affected by the magnetic force of the amplitude control weight 51.

As another example in which the weight of the amplitude control weight 51 can be increased or decreased, an electromagnetic coil (not shown) that generates a magnetic flux is provided in the amplitude control weight 51, and the magnetic force generated by the electromagnetic coil causes The weight of the amplitude control weight 51 may be increased by adsorbing the metal piece provided in the shield case 71. Also in this case, the electromagnetic coil and the movable part are installed separately from each other so that the magnetic force generated by the electromagnetic coil does not affect the reciprocating motion of the movable part.

As yet another example in which the weight of the amplitude control weight 51 can be increased and decreased, as shown in FIG. 24, the amplitude control weight 51 is formed so that its inside is hollow, and
A communication hole 51b may be provided to connect the hollow portion 51a and the surface of the amplitude control weight 51. 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 via the communication hole 51b to close the communication hole 51b. On the contrary, if you want to reduce the weight,
It is sufficient to leave nothing in a and leave it as a void. Moreover,
If a gas having a smaller specific gravity than air is injected to block the communication hole 51b, the weight can be further reduced.

FIG. 25 shows an example of another embodiment , in which the amplitude control weight 51 is provided with a through hole 51d penetrating in the reciprocating direction thereof. When the amplitude control weight 51 reciprocates, the air inside the linear oscillator also moves in response to the reciprocation.
If it is made of a non-breathable material such as iron material, the air inside the linear oscillator will move to the amplitude control weight 51 when reciprocating.
And the shield case 71 move while being compressed. That is, the amplitude control weight 51 receives resistance from the air existing between the amplitude control weight 51 and the shield case 71 during its reciprocating motion.

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

FIG. 26 shows an example corresponding to the invention of claim 30 in which the amplitude control weight 51 is provided in the shield case 71.
The through hole 71b is provided so as to pass through 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 its reciprocating motion. Further, like the amplitude control weight 51, the blanker 11 also receives resistance from air during its reciprocating motion. In this embodiment, since the through-hole 71b is provided in the shield case 71, when the amplitude control weight 51 and the blanker 11 reciprocate, air moves through the through-hole 71b in accordance with the reciprocating movement of the linear oscillator. Since the inside and outside can be freely moved in and out, the air resistance applied to the amplitude control weight 51 and the blanker 11 can be reduced, the loss of the reciprocating motion of the movable part and the amplitude control weight 51 is reduced, and the output amplitude is increased. can do.

FIG. 27 shows an example corresponding to the sixteenth aspect of the present invention, in which the spring 92 is moved relative to the shield case 71 when the movable part and the amplitude control weight 51 reciprocate in the secondary mode of opposite phase. The immobile portion and the shield case 71 are connected by an elastic body 63. This is because when the linear oscillator receives a shock from the outside when the control is performed using a feedback circuit that detects the motion state of the blanker 11 and applies the optimum voltage for the reciprocating motion, the reciprocating motion is changed from the secondary mode. , The movable part and the amplitude control weight 51 may shift to the primary mode in which they reciprocate in the same phase. Therefore, in this embodiment, the spring 9 in the secondary mode is used.
The second fixed point 92a and the shield case 71 are connected to each other by an elastic body 63.
Therefore, when trying 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.

Although the elastic body 63 is used as the connecting means in this case, when the elastic body 63 is composed of a member having no elasticity, the force for shifting from the secondary mode to the primary mode is a member. This is because the member may be damaged if the strength is higher than the above. On the contrary, when the elastic force of the elastic body 63 is small, the reciprocating movement of the spring 92 cannot be stopped,
It may shift to the primary mode. Therefore, the elastic body 63 has an elastic force of a predetermined value or more, for example,
Hard rubber, plastic, thin plate metal, etc. can be used.

FIG. 28 shows an example corresponding to the invention of claim 17 , in which a first mounting portion (hereinafter, mounting portion 85a), a second mounting portion (hereinafter, mounting portion 85b), and a connecting portion 85c are provided. The link 85 provided is provided. The mounting portion 85a is attached to the blanker 11, and the mounting portion 85a
b is screwed and connected to the amplitude control weight 51, and the connecting portion 85c
Are screwed to the shield case 71.

In the link 85, the mounting portion 85a and the mounting portion 85b rotate symmetrically about the connecting portion 85c connected and fixed to the shield case 71 by the same distance. With this link 85, the blanker 11 and the amplitude control weight 51, which are respectively connected to the mounting portions 85a and 85b, operate in opposite directions and with the same amplitude, and the vibration canceling action of the amplitude control weight 51 is more effective. 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 an impact applied to the linear oscillator or the like.

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 reciprocating movable part, a case that houses the movable part, and a movable part that is movably supported by the case can be moved separately. In the linear oscillator including the width control weight, the movable part and the amplitude control weight reciprocate at the resonance frequency of the linear oscillator or a frequency in the vicinity thereof, so that the electric energy is directly applied to the plunger. Since it can be converted into linear reciprocating motion, a motion conversion mechanism for converting rotational motion into linear motion is unnecessary, and unnecessary vibration can be canceled by a vibration absorbing weight, so it is low noise and small in size. It is possible to obtain a linear oscillator with extremely low vibration, and it can be suitably used for a drive unit for machine control, a drive unit for an electric razor, an electric toothbrush, and the like.

Further, if the movable part and the amplitude control weight reciprocate in opposite phases, the amplitude control weight performing the opposite phase motion cancels out the inertial force of the movable part, and conversely the inertial force of the amplitude control weight. The movable part cancels out the vibration, and the vibration of the linear oscillator becomes minimum.

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 portion can be made larger.

Further, if 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 reducing effect can be obtained.

Further, when 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 portion, the stroke of the movable portion can be further increased.

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 convenient linear oscillator can be obtained.

At least the portion of the case that faces the electromagnetic drive portion is made of a magnetic material, and the thickness of the magnetic material of the portion that faces the electromagnetic drive portion is 7 times the outer diameter of the permanent magnet.
If it is at least%, it is possible to obtain a linear oscillator having a high magnetic efficiency and a magnetic leakage level that does not affect a pacemaker or the like.

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

If the first yoke is formed so as to have a triangular cross section in which the side facing the case is an inclined surface,
The thrust can be further improved.

If part or all of the shaft is made non-magnetic, the thrust can be improved and the magnetic flux leakage through the shaft can be eliminated.

Further, if the portion of the shaft connected to the movable portion that penetrates the movable portion is made non-magnetic, it is possible to improve the thrust without lowering the wear resistance.

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

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

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

Further, the movable portion is provided with 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 provided on the coil side end surface of the second yoke. If the end face of the movable part in the reciprocating direction is made to substantially coincide with the end face of the permanent magnet on the first yoke side, the detent force near the neutral position can be made almost zero, and the resonance system Design can be done easily.

Further, 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 rotational direction around the axis, a force in the rotational direction is generated depending on the stroke position to cause linear movement. The rotational movement can also be performed at the same time.

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

If the spring member is used as the rotation restricting means,
The rotation can be restricted without the need for a separate member.

Further, the relative position between the end surface of the permanent magnet on the first yoke side and the end surface of the movable portion in the reciprocating direction is adjusted according to the detent force generated in the electromagnetic drive portion to maximize the amplitude of the movable portion. By setting the frequency that is 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.

If the shaft is supported in the axial direction and a bearing having frictional force changing means for changing the frictional force generated between the shaft and the shaft is changeably connected to the case, the amplitude can be controlled. Becomes

A bearing having a frictional force changing means for supporting the shaft connected to the movable part in the axial direction thereof and changing the frictional force generated between the shaft connected to the movable part so as to be adjustable, If it is provided between the movable part and the amplitude control weight by connecting it to the case, it is not necessary to penetrate the shaft to the amplitude control weight, so that the mass of the movable part can be reduced and vibration can be reduced, and at the same time, the amplitude control weight can be reduced. Since it is not necessary to provide a hollow portion through which the shaft is passed, 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 increased or decreased, the resonance characteristic can be made variable and the amplitude can be controlled.

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

Further, if the case is provided with a through hole penetrating in the vibration direction of the amplitude control weight, the air resistance can be reduced and the amplitude can be increased during the reciprocating movement of the movable part and the amplitude control weight. It will be possible.

In addition, when the movable part and the amplitude control weight move in opposite phases, they become immovable with respect to the case of the second spring,
If the 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 to be rotatable in symmetrical directions. If the link means is also provided, the movable portion and the amplitude control weight can always be operated in opposite phases, and it is possible to prevent them from operating in the same phase.

[Brief description of 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 same as above.

[Equation 1] is a motion equation of the above-described spring vibration system model.

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

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

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

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

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

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

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

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

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

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

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

14A is a positional relationship between a blanker and a yoke in the sectional view taken along the line A in the same, and FIG. 14B is a positional relationship between the blanker and a yoke in the sectional view taken along the line B in the same;
(C) is a figure which shows the positional relationship of the blanker and yoke in the C line sectional view same as the above.

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

FIG. 16 is a partial cross-sectional view showing a supporting relationship between the amplitude control weight, the case and the above.

FIG. 17 is another sectional view of the above.

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

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

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

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

FIG. 22 is a cross-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 cross-sectional view of another example of the same.

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

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

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

[Explanation of symbols]

11 Brander 11a slit 12 axes 31 York 32 York 33 York 34 York 51 Amplitude control weight 51a hollow part 51b communication hole 51d through hole 52 bearing 53 bearing 61 coils 63 Elastic body 71 shield case 71b through hole 81 permanent magnet 82 Permanent magnet 85 links 85a mounting part 85b mounting part 87 bearings 89 bearings 91 spring 92 spring 92a Fixed point 93 spring 94 leaf spring 95 leaf spring 96 leaf spring

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuya Hasegawa 1048, Kadoma, Kadoma, Osaka Prefecture, Matsushita Electric Works, Ltd. (72) Inventor, Eiichi Yabuuchi, 1048, Kadoma, Kadoma, Osaka (72, Matsushita Electric Works, Ltd.) ) Inventor Hiromitsu Inoue 1048 Kadoma, Kadoma City, Osaka Prefecture, Matsushita Electric Works Co., Ltd. (72) Tomio Yamada, 1048 Kadoma, Kadoma City, Osaka Prefecture, Matsushita Electric Works Co., Ltd. (56) Reference JP 2000-166209 (JP) , A) JP-A-11-178305 (JP, A) JP-A-11-187638 (JP, A) JP-A-9-205763 (JP, A) Actually open 5-70164 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02K 33/02 B06B 1/04 B26B 19/28 A61C 17/22

Claims (18)

(57) [Claims] 1. A movable portion of reciprocable, separately moving This a case for housing the movable portion, and the movable portion supported by the movable into the casing
Preparative an amplitude control weight, which can, a linear oscillator having a movable portion and the amplitude control weight is a linear oscillator, characterized in that reciprocate at a resonance frequency or a frequency near the of the linear oscillator. 2. An electromagnetic drive unit disposed inside the case for reciprocatingly driving the movable unit, 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 that forms a vibration system, wherein a resonance frequency of the spring vibration system is a resonance frequency of the linear oscillator or a frequency in the vicinity thereof. 3. The spring member includes a first spring arranged between the case and the movable portion, a second spring arranged between the movable portion and the amplitude control weight, and the amplitude. The third oscillator provided between the control weight and the case, and the linear oscillator according to claim 2. 4. The linear oscillator according to claim 2, wherein the electromagnetic drive unit includes a coil, and a reciprocating motion of the movable unit is controlled by a coil current flowing through the coil. 5. The coil is arranged on the outer periphery of the movable part, and the electromagnetic drive part is provided with second yokes respectively arranged on both end faces of the coil, and with respect to the center of the coil. A pair of permanent magnets magnetized in a symmetrical direction and disposed on the end surface of the second yoke opposite to the coil, and a pair of permanent magnets disposed on the side opposite to the second yoke of the permanent magnet. 5. The linear oscillator according to claim 4, characterized in that the linear oscillator comprises: 6. The movable part also includes a shaft for extracting a motion output, and the shaft is provided so as to be connected to the movable part or the amplitude control weight. Item 6. The linear oscillator according to any one of items 5. 7. The movable part also includes a first shaft and a second shaft, and the first shaft is connected to the movable part and the second shaft is connected to the amplitude control weight. 6. The motion output is taken out from at least one of the first axis and the second axis.
The linear oscillator according to any one of 1. 8. The movable part and the amplitude control weight reciprocate in opposite phases.
The linear oscillator according to any one of 1. 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. A pre-Symbol case, together with the portion facing at least the electromagnetic drive unit is formed of a magnetic material, a thickness of the magnetic material of the portion facing the electromagnetic drive unit, outside of the permanent magnet It is 7% or more of a diameter, The linear oscillator in any one of Claim 5 thru | or 9 characterized by the above-mentioned. 11. The linear oscillator according to any one of claims 5 to 1 0, characterized in that it also comprises a magnetic flux increasing means for increasing the magnetic flux around the movable portion. 12. The movable part has a large diameter part at both ends in the reciprocating direction, and a small diameter part at the center part, and a boundary surface between the large diameter part and the small diameter part, and a second yoke part of the second yoke. said substantially to match the end surface of the coil side, the reciprocating direction end surface of the movable portion, the claims 5 to, characterized in that it substantially coincide on the end face of the first yoke side of the permanent magnet 11 The linear oscillator according to any one of 1. 13. The method of claim 6 to claim 1, characterized in that it also includes a rotation restricting means for restricting the rotation of said shaft
2. The linear oscillator according to any one of 2. 14. The linear oscillator according to claim 1 3, characterized in that said spring member is set to the rotation restricting means. 15. The movable position is adjusted by adjusting the relative position between the end face of the permanent magnet on the side of the first yoke and the end face of the movable unit in the reciprocating direction according to the detent force generated in the electromagnetic drive unit. The linear oscillator according to any one of claims 5 to 14 , wherein the frequency at which the amplitude of the portion is maximum is brought close to the resonance frequency of the spring vibration system. 16. A connection means for connecting the case and the portion of the second spring that is immovable with respect to the case when the movable portion and the amplitude control weight move in opposite phases. The linear oscillator according to any one of claims 3 to 15 , which is characterized. 17. A first mounting part connected to the movable part and a second mounting part connected to the amplitude control weight, wherein the first mounting part and the second mounting part are symmetrical. linear oscillator according to any one of claims 1 to 16, characterized in that also comprises a link means formed so as to be rotatable in the direction. 18. The movable part, which is disposed in the case,
A spring member that is disposed at least between the electromagnetic drive unit that reciprocates and the case and the movable unit, and between the case and the amplitude control weight to form a spring vibration system.
9. The method according to claim 1, further comprising:
The linear oscillator according to any one of 1 .