WO2022054770A1 - Electromechanical converter - Google Patents

Abstract

Provided is an electromechanical converter comprising: a structure part that has two pairs of magnets which have different magnetic poles thereof facing each other, yokes which guide, in a closed-circuit manner, magnetic flux produced by the magnets, and a coil which is disposed in an internal space surrounded by the yokes; an armature that is disposed so as to penetrate, in the winding direction of the coil, through the internal space of the structure part; elastic members that are disposed so as to sandwich the armature therebetween and to form a pair between the yokes and that support the armature in the internal space; and abutting parts that cause the elastic members and the yokes to abut such that regions of contact with the elastic members are linear.

Description

Electromechanical transducer

The present invention relates to an electromechanical transducer that converts an electrical signal into mechanical vibration.

In this kind of electromechanical converter, for example, two pairs of magnets, a yoke that guides the magnetic flux by these magnets, and a coil to which an electric signal is supplied are integrally arranged to form a structural part, and in the internal space thereof. Two pairs of elastic members arranged so as to penetrate the armature and symmetrically arranged across the armature to support the armature in a displaceable manner (see, for example, Patent Documents 1 and 3), and a pair of elastic members in the same manner. Those that support it (see, for example, Patent Document 2) are known.

The above-mentioned pair or two pairs of elastic members (springs) are sandwiched between the yoke and the armature and deformed, and the armature is applied to the yoke at the point where the elastic forces (restoring force) of each other are balanced. Position relatively. At this time, the armature is required to be correctly positioned along the structural (design) central axis due to the relationship with the yoke, but the elastic force acting on the armature due to variations in the processing accuracy of the elastic member is unreasonable. When balanced, the armature may tilt from the central axis and may not be properly positioned. Such an inclination of the armature can be suppressed to some extent by adopting a structure in which the moment of the force acting on the armature around the central axis is as small as possible (see the technical matters of Patent Document 3).

Japanese Patent Application Laid-Open No. 2015-139041 Japanese Patent Laid-Open No. 2018-186378 Japanese Patent Laid-Open No. 2019-193218

The above-mentioned method for reducing the moment of the force applied to the armature around the central axis (Patent Document 3) specifically relates to a structure using two pairs of elastic members (Patent Document 1), and the pair of elastic members. It cannot be immediately applied to the structure using (Patent Document 2). In addition, since some variation is unavoidable in machining, it is difficult to realize machining with perfect accuracy in which an elastic force is applied to an armature at a distance completely symmetrical to the central axis. In both structures, the imbalance of the force acting between the yoke and the elastic member tilts the armature from its regular position and adversely affects its performance as an electromechanical converter, thus yielding in the manufacturing process. There is a problem that (incidence rate of defective products) becomes worse.

The present invention provides a technique for suppressing an adverse effect on performance.

The present invention provides an electromechanical transducer. In an electromechanical converter, an armature is placed in the internal space of a structural part consisting of a magnet, a yoke, and a coil, and the armature is displaceably supported by the elastic force of an elastic member paired between the armature and the yoke. Is. In such a basic configuration, the electromechanical transducer has a "contact portion" as a unique configuration.

That is, the "contact portion" having the above configuration has a linear contact region with the elastic member, and the elastic member and the yoke are brought into contact (contact). In this case, since the points of action of the force between the yoke and the elastic member can be concentrated within the linear range, the points of action of the force are not widely dispersed over a distance. Therefore, by arranging the range where the points of action of such force are concentrated symmetrically with the armature in between, the torque of the force that causes the tilt of the armature can be suppressed to a very small size.

Therefore, it is preferable that the "contact portion" is symmetrical with respect to the central axis of the structural portion and the contact region with the elastic member is arranged on the axes parallel to each other. The central axis of the structural portion may be either a central axis along the penetrating direction of the armature or a central axis orthogonal to the penetrating direction of the armature. In any case, by arranging the linear contact regions symmetrically with the central axis of the structural portion sandwiched by the "contact portion" on the axes parallel to each other, the point of action of the force becomes the central axis as described above. It is positioned symmetrically and concentrated on the parallel axis. This prevents torque around the central axis from being generated due to the imbalance of the force acting between the yoke and the elastic member, and suppresses the tilt of the armature to prevent deterioration of the performance of the electromechanical converter during the manufacturing process. It is possible to prevent the deterioration of the yield.

Further, as the "contact portion", the following preferred embodiment can be adopted in relation to the elastic member.
[First aspect]
The first aspect is a mode in which the "contact portion" is curved and comes into contact with the elastic member.
That is, the elastic member has a leaf spring-like facing portion that is sandwiched between the armature and the yoke and is deformed, and is in contact with the curved surface of the "contact portion" to exert an elastic force. In this case, the facing portion bends and bends in the deformed state of the elastic member, but if the radius of curvature appearing at the facing portion at this time is R1, the radius of curvature R2 of the curved surface of the "contact portion" is better. Small (R1> R2). As a result, the contact area between the facing portion in the curved and bent state (curved surface state) and the curved surface of the "contact portion" is preferably linear, and the point of action of the force can be concentrated on the contact area. ..

[Second aspect]
The second aspect is an aspect in which the "contact portion" comes into contact with the elastic member at the edge (edge).
That is, the elastic member has a leaf spring-shaped facing portion as in the first aspect, but the "contact portion" has an edge having a convex shape with respect to the leaf spring-shaped facing portion. In this case, the "contact portion" can preferably make the contact region with the elastic member linear while keeping the shape of the edge, and concentrate the point of action of the force on the contact region.

Further, in the second aspect, the facing portion is curved and bent in the deformed state of the elastic member. At this time, if the opening angle centered on the contact region appearing in the facing portion is θ1, the edge is opened. The angle θ2 is smaller (θ1> θ2). Therefore, the leaf spring-like facing portion can come into contact with a sharper edge in a flexed state, and the point of action of the force can be concentrated in the contact region.

As described above, according to the present invention, it is possible to suppress adverse effects on the performance as an electromechanical transducer.

It is a perspective view which shows the electromechanical transducer 100 of 1st Embodiment. It is an exploded perspective view of the electromechanical transducer 100. It is sectional drawing of the electromechanical converter 100 along the line III-III in FIG. It is sectional drawing of the electromechanical converter 100 along the IV-IV line in FIG. It is sectional drawing of the electromechanical converter 100 at the position along the VV line in FIG. 1. It is sectional drawing of the electromechanical converter 100 at the position along the VV line in FIG. 1. It is a figure which shows the 2nd aspect of the structure in the same cross-sectional position as FIG. It is a figure which shows the 2nd aspect of the structure in the same cross-sectional position as FIG. It is a perspective view which shows the electromechanical transducer 200 of 2nd Embodiment. It is an exploded perspective view of the electromechanical transducer 200. It is sectional drawing of the electromechanical transducer 200 along the IX-IX line in FIG. 7. It is sectional drawing of the electromechanical converter 200 along the XX line in FIG. 7. It is sectional drawing of the electromechanical converter 200 at the position along the XI-XI line in FIG. 7. It is sectional drawing of the electromechanical converter 200 at the position along the XI-XI line in FIG. 7. It is a figure which shows the 2nd aspect of the structure in the same cross-sectional position as FIG. It is a figure which shows the 2nd aspect of the structure in the same cross-sectional position as FIG.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The electromechanical converters shown in some embodiments below are, for example, used for converting electrical signals into mechanical vibrations, as well as electroacoustics such as speakers and earphones that convert electrical signals into sound (sound) by the mechanical vibrations. It can be applied to converters.

[First Embodiment]
FIG. 1 is a perspective view showing the electromechanical transducer 100 of the first embodiment. FIG. 2 is an exploded perspective view of the electromechanical converter 100. In the basic structure of the electromechanical converter 100, the armature 120 is arranged through the internal space of the structural part (both without reference numerals) in which the magnets 110, 112, 114, 116, the yokes 102, 104 and the coil 118 are integrally arranged. The armature 120 is supported by two pairs of elastic members 106, 108 sandwiched between the yokes 102 and 104.

Since such a basic structure is already known, details thereof will be omitted, but both edges of the two yokes 102 and 104 paired up and down in FIGS. 1 and 2 are bent in the direction of mutual combination. Two bent portions 102a and 104a are formed symmetrically. In the completed state of FIG. 1, the upper and lower yokes 102 and 104 are pressure-welded at the opposing joint surfaces of the bent portions 102a and 104a and integrally joined (for example, laser welding).

Further, two magnets 110 and 112 are fixed to the inner surface of the upper yoke 102 by adhesion with an interval in the longitudinal direction thereof, and the inner surface of the lower yoke 104 is also spaced in the longitudinal direction. Two magnets 114 and 116 are fixed by adhesion. In the completed state, the square plate-shaped magnets 110 and 114 facing up and down on one side in the longitudinal direction form one pair, and the square plate-shaped magnets 112 and 116 facing up and down on the other side form another pair. ing. The paired magnets 110 and 114 have different poles facing each other, and the magnets 112 and 116 have different poles facing each other (S pole-N pole). Further, the two magnets 110, 112 arranged side by side in the longitudinal direction on the inner surface of each of the same yokes 102, 104 are magnetized in opposite directions to each other, and similarly, the magnets 114, 116 are magnetized to each other. The polarity is magnetized in the opposite direction. As a result, in the completed state, the two yokes 102 and 104 guide the magnetic flux due to the two pairs of magnets 110 and 114 and the magnets 112 and 116 in a closed circuit.

The coil 118 is arranged in the center in the longitudinal direction in the internal space surrounded by the yokes 102 and 104, that is, between the pair of magnets 110 and 114 and the pair of magnets 112 and 116. The coil 118 is an air-core type having no core, and the direction of the winding center thereof coincides with the longitudinal direction of the entire structural portion. The outer peripheral surface of the coil 118 is partially exposed on both sides from between the bent portions 102a and 104a in the lateral direction (direction orthogonal to the longitudinal direction) of the structural portion. , Coil terminals 122 and 124 are soldered, respectively. The coil terminals 122 and 124 allow the winding start end and winding end end of the coil 118 to be connected to the outside, respectively. The coil 118 is fixed to the inner surfaces of the yokes 102 and 104 by adhesion in an insulated state.

The armature 120 is arranged so as to penetrate the internal space of the structural portion in the longitudinal direction, that is, in the winding center direction of the coil 118. The armature 120 has a flat plate shape on both sides facing the upper and lower square plate-shaped magnets 110 and 112 and the magnets 114 and 116, respectively, and both ends in the longitudinal direction project outward from the internal space. At both ends of such a protruding armature 120, contact portions 120a and 120b with elastic members 106 and 108 are formed on the upper surface and the lower surface, respectively.

On the other hand, the upper and lower yokes 102 and 104 are formed with contact portions 102b and 104b protruding from the internal space on both sides in the longitudinal direction, and the yokes 102 and 104 are elastic at the contact portions 102b and 104b, respectively. Contact with members 106, 108. These contact portions 102b and 104b are located on the central axis in the longitudinal direction of the yokes 102 and 104, respectively, and in the center in the lateral direction. This point will be further described later.

The upper and lower pairs of elastic members 106 and 108 are formed by bending a thin plate-shaped spring member, and as a single body, the entire body has a notched elliptical shape or a "3" cross-sectional shape. The elastic members 106 and 108 are in contact with the upper and lower yokes 102 and 104 at only one contact portion 102b and 104b, respectively. Therefore, in each of the elastic members 106 and 108, the central portion corresponding to the contact portions 102b and 104b is processed into a groove-shaped cross-sectional shape, and the portion corresponding to the groove bottom is a leaf spring-shaped facing portion 106a, It is formed as 108a.

Further, each of the elastic members 106 and 108 is formed as curved portions 106c and 108c in which portions extending from the central facing portions 106a and 108a on both sides are bent into a U-shaped cross-sectional shape, respectively, and the curved portions 106c and 108c are formed. The terminal portions connected to the above are formed as contact portions 106b and 108b having a key (Γ) type cross-sectional shape, respectively. The elastic members 106 and 108 are in contact with the armature 120 at two points on both the upper and lower sides at the end contact portions 106b and 108b, and the upper elastic member 106 is in contact with the contact portion 106b on the upper surface side of the armature 120. It comes into contact with 120a, and the lower elastic member 108 comes into contact with the contact portion 120b on the lower surface side of the armature 120 at the contact portion 108b.

In the completed state of the electromechanical converter 100, the elastic members 106 and 108 are sandwiched between the upper and lower yokes 102 and 104 and the armature 120 with a predetermined displacement amount (deformation amount). As a result, the armature 120 is supported at a position where these forces are in equilibrium while receiving elastic forces (repulsive forces) of the upper and lower pairs of elastic members 106 and 108, and an appropriate gap (air gap) is provided between the armature 120 and the structural portion. Is placed with. In the disassembled state of FIG. 2, the elastic members 106 and 108 are shown in a deformed state as in FIG. 1, but in the free state (no load), the facing portions 106a and 108a of the elastic members 106 and 108 are shown. Is a flat plate, and the facing portions 106a and 108a and the end contact portions 106b and 108b are parallel to each other without being crushed as a whole.

A soft magnetic material such as permalloy of 45% Ni is used for the yokes 102 and 104 and the armature 120, and a stainless steel material such as SUS301 for springs is used for the elastic members 106 and 108.

[Relationship with the central axis]
Next, the relationship with some central axes defined in the structural part of the electromechanical converter 100 will be described. The central axis is defined in, for example, three directions (so-called XYZ axes) when the structural portion is captured three-dimensionally.

[Central axis A1]
FIG. 3 is a cross-sectional view of the electromechanical converter 100 along lines III-III in FIG. Assuming that the longitudinal direction of the structural portion seen in FIG. 1 is, for example, the horizontal direction, the cross section shown in FIG. 3 is the horizontal cross section (the XY axis direction cross section) of the electromechanical converter 100. As shown in FIG. 3, a horizontal central axis A1 in the longitudinal direction can be defined in the structural portion of the electromechanical converter 100. The members constituting the structural parts such as the magnets 110, 112, 114, 116, the yokes 102, 104, and the coil 118 are all symmetrically arranged in the horizontal direction (XY plane) with the central axis A1 as a common one. ..

[Armature tilt (1)]
Here, regarding the inclination of the armature 120 which adversely affects the performance of the electromechanical converter 100, it is structurally unlikely that the armature 120 is tilted in the arrow H direction (horizontal direction) in FIG. 3 with respect to the central axis A1. This is because the elastic members 106 and 108 supporting the armature 120 do not exert a force in the direction of arrow H between the elastic members 106 and 108 and the yokes 102 and 104, so that the force imbalance is unlikely to occur due to the structure. ..

FIG. 4 is a cross-sectional view of the electromechanical converter 100 along the IV-IV line in FIG. When FIG. 3 is a horizontal cross-sectional view, FIG. 4 is a vertical cross-sectional view in the longitudinal direction (cross-sectional view in the XX-axis direction). As shown in FIG. 4, the members constituting the structural portion such as the magnets 110, 112, 114, 116, the yokes 102, 104, and the coil 118 are all the central axis A1 in the vertical direction (YZ direction). It can be seen that they are arranged symmetrically as a common one.

[Armature tilt (2)]
Here, the armature 120 may be tilted in the arrow V direction (vertical direction) in FIG. 4 with respect to the central axis A1, but this is hardly a problem. The inclination of the armature 120 in the arrow V direction occurs when the imbalance of the force acting between the upper and lower elastic members 106, 108 and the yokes 102, 104 is extremely large in the structure of the present embodiment, but this is usually the case. This is because the imbalance of such force can be suppressed to a small level, so that it does not matter even if the variation in machining is taken into consideration.

[Central axis lines A2 and A3]
Next, FIGS. 5A and 5B are cross-sectional views of the electromechanical converter 100 at positions along the VV line in FIG. When FIG. 4 is a vertical cross-sectional view in the longitudinal direction (XZ-axis direction cross-sectional view), FIGS. 5A and 5B are vertical cross-sectional views in the lateral direction (YZ-axis direction cross-sectional view). Further, FIG. 5A is an overall cross-sectional view, and FIG. 5B is an enlarged partial cross-sectional view of the range surrounded by the alternate long and short dash line of FIG. 5A. As shown in FIG. 5A, the structural portion of the electromechanical converter 100 can be defined with a horizontal central axis A2 in the lateral direction and a central axis A3 in the vertical direction. .. It can be seen that the various members constituting the structural portion are symmetrically arranged in the vertical direction (YZ plane) with the central axis A2 and the central axis A3 common. The central axis A1 in the longitudinal direction (no reference numeral in FIGS. 5A and 5B) is located on the intersection of the central axis A2 and the central axis A3.

[Armature tilt (3)]
Here, the inclination of the armature 120 in the arrow L direction (vertical direction) of FIG. 5A with respect to the central axis A2 can be a problem. The inclination of the armature 120 in the direction of the arrow L has the same meaning for the central axis A3, but with respect to the central axis A1, it means the inclination around the central axis A1 (rotational direction). It has already been found that such an inclination becomes a problem mainly when an imbalance of forces acting between the yokes 102 and 104 and the elastic members 106 and 108 can occur mainly in the direction of the central axis A2. (See Patent Document 3 in the Prior Art Document).

In view of the structural factors that cause the armature 120 to tilt as described above, the present invention realizes a structure that does not cause an imbalance in the force acting between the yokes 102 and 104 and the elastic members 106 and 108. .. The structure is realized by a plurality of aspects listed below.

[First aspect]
FIG. 5A: The first aspect of this structure is a structure in which the contact portions 102b and 104b of the yokes 102 and 104 come into contact with the elastic members 106 and 108 on a curved surface. That is, assuming that the facing portions 106a and 108a are flat plates in a free state (not shown) of the elastic members 106 and 108, the contact portions 102b and 104b in contact with them are formed on a curved surface instead of a flat surface. Therefore, the contact region between the contact portions 102b and 104b and the facing portions 106a and 108a has a linear shape extending in the central axis A1 direction. As a result, the points of action of the forces F acting on the elastic members 106 and 108 from the contact portions 102b and 104b of the yokes 102 and 104 are substantially linearly narrowed and concentrated, so that the forces F are concentrated in the direction of the central axis A2. The points of action of are not dispersed. Therefore, the width between the points of action of the force spreading in the central axis A2 direction, which has become a problem in the prior art (Patent Document 3 and the like), can be made almost zero (zero), and the above-mentioned problem can be solved.

FIG. 5B: The curved surface formed on the contact portions 102b and 104b can be preferably defined by the following indexes. For example, taking the upper contact portion 102b as an example, the facing portion 106a is deformed due to bending in the deformed state of the elastic member 106, but the radius of curvature R1 appearing in the facing portion 106a in this bending state is higher than that of the radius of curvature R1. The radius of curvature R2 of the curved surface formed on the contact portion 102b is reduced (R1> R2). As a result, as described above, the contact region between the contact portion 102b on the yoke 102 side and the facing portion 106a of the elastic member 106 is narrowed linearly in the direction of the central axis A2, and the points of action of the force F are almost non-dispersed ( It is suppressed to zero).

Since the contact portions 102b and 104b of the yokes 102 and 104 are arranged vertically symmetrically with respect to the central axes A1 and A2 of the structural portion, the forces F received by the elastic members 106 and 108 from the upper and lower yokes 102 and 104. Does not stagger from the central axes A1 and A3, and the generation of torque that causes the tilt of the armature 120 in the direction of the arrow L shown in FIG. 5A can be suppressed to a very small value.

[Second aspect]
6A and 6B are views showing a second aspect of the structure at the same cross-sectional positions as FIGS. 5A and 5B. Of these, FIG. 6A is an overall cross-sectional view, and FIG. 6B is an enlarged partial cross-sectional view of the range surrounded by the alternate long and short dash line of FIG. 6A.

FIG. 6A: In the second aspect, the contact portions 302b and 304b different from those in the first aspect are formed on the yokes 102 and 104, but the other aspects are the same as in the first aspect. In such a second aspect, the contact portions 302b and 304b are in contact with the elastic members 106 and 108 at the edges (edges). Similarly, assuming that the facing portions 106a and 108a are flat plates in a free state (not shown) of the elastic members 106 and 108, the contact portions 302b and 304b in contact with them are not planar and the facing portions 106a are not formed. , 108a is formed in a convex shape (mountain shape), and the contact portion thereof has an edge shape. Therefore, the contact region between the contact portions 302b and 304b and the facing portions 106a and 108a is also a straight line extending in the central axis A1 direction. As a result, the points of action of the forces F acting on the elastic members 106 and 108 from the contact portions 302b and 304b of the yokes 102 and 104 are substantially linearly narrowed and concentrated, so that the forces F are concentrated in the direction of the central axis A2. The above-mentioned problems can be solved by making the width between the points of action of the force spreading in the central axis A2 direction almost zero (zero) without dispersing the points of action of the above.

FIG. 6B: The edges formed in the contact portions 302b and 304b can be preferably defined by the following indexes. Similarly, for example, taking the upper contact portion 302b as an example, the facing portion 106a is deformed due to bending in the deformed state of the elastic member 106, but the contact region appearing in the facing portion 106a in this bending state. The opening angle θ2 of the edge formed on the contact portion 302b is made smaller than the opening angle θ1 centered on (θ1> θ2). As a result, as described above, the contact region between the contact portion 302b on the yoke 102 side and the facing portion 106a of the elastic member 106 is narrowed linearly in the direction of the central axis A2, and the point of action of the force F is almost non-dispersed (). It is suppressed to zero).

Since the contact portions 302b and 304b of the yokes 102 and 104 are arranged vertically symmetrically with respect to the central axis A1 (no reference numeral in FIGS. 6A and 6B) and A2 of the structural portion, the upper and lower yokes 102 and 104 The forces F received by the elastic members 106 and 108 do not stagger from the central axes A1 and A3, and the generation of torque that causes the tilt of the armature 120 in the direction of the arrow L shown in FIG. 6A is suppressed to a very small value. Can be done.

[Second Embodiment]
Next, a second embodiment of the electromechanical converter will be described.
FIG. 7 is a perspective view showing the electromechanical transducer 200 of the second embodiment. Further, FIG. 8 is an exploded perspective view of the electromechanical converter 200. The basic structure of the electromechanical converter 200 is an armature 220 that penetrates the internal space of the structure in which the magnets 210, 212, 214, 216, yokes 202, 204 and coils 218 are integrally arranged (both figures have no reference code). The armature 220 is supported by a pair of elastic members 206, 208 sandwiched between the yokes 202 and 204.

As described above, the electromechanical transducer 200 of the second embodiment is different from the first embodiment in that the armature 220 is supported by the pair of elastic members 206 and 208. However, since there are many parts in common with the first embodiment in the configuration other than the contact between the elastic members 206, 208 and the yokes 202, 204, the description of the parts in common with the first embodiment will be omitted below (see). The reference numeral is changed from the 100 series of the first embodiment to the 200 series).

Also in the second embodiment, two bent portions 202a and 204a bent in the direction of combination with each other are symmetrically formed on both side edges of the two yokes 202 and 204 paired vertically in FIGS. 7 and 8. It is formed. In the completed state of FIG. 7, the upper and lower yokes 202 and 204 are pressure-welded at the opposing joint surfaces of the bent portions 202a and 204a and integrally joined (for example, laser welding).

Further, two magnets 210 and 212 are fixed to the inner surface of the upper yoke 202 by adhesion with an interval in the longitudinal direction thereof, and the inner surface of the lower yoke 204 is also spaced in the longitudinal direction. Two magnets 214 and 216 are fixed by adhesion. In the completed state, the square plate-shaped magnets 210 and 214 facing up and down on one side in the longitudinal direction form one pair, and the square plate-shaped magnets 212 and 216 facing up and down on the other side form another pair. ing. The paired magnets 210 and 214 face each other with different poles (S pole-N pole), and the magnets 212 and 216 face each other with different poles. Further, the two magnets 210, 212 arranged side by side in the longitudinal direction on the inner surface of each of the same yokes 202, 204 are magnetized in opposite directions to each other, and similarly, the magnets 214, 216 are magnetized to each other. The polarity is magnetized in the opposite direction. As a result, in the completed state, the two yokes 202 and 204 guide the magnetic flux due to the two pairs of magnets 210 and 214 and the magnets 212 and 216 in a closed circuit.

The coil 218 is arranged in the center in the longitudinal direction in the internal space surrounded by the yokes 202 and 204, that is, between the pair of magnets 210 and 214 and the pair of magnets 212 and 216. The coil 218 is an air-core type having no core, and the direction of the winding center thereof coincides with the longitudinal direction of the entire structural portion. The outer peripheral surface of the coil 218 is partially exposed on both sides from between the bent portions 202a and 204a in the lateral direction (direction orthogonal to the longitudinal direction) of the structural portion. , The coil terminals 222 and 224 are soldered, respectively. The coil terminals 222 and 224 make it possible to connect the winding start end and the winding end end of the coil 218 to the outside, respectively. The coil 218 is fixed to the inner surfaces of the yokes 202 and 204 by adhesion in an insulated state.

The armature 220 is arranged so as to penetrate the internal space of the structural portion in the longitudinal direction, that is, in the winding center direction of the coil 218. The armature 220 has a flat plate shape on both sides facing the upper and lower square plate-shaped magnets 210, 212 and magnets 214, 216, respectively, and both ends in the longitudinal direction project outward from the internal space. At both ends of such a protruding armature 220, contact portions 220a and 220b with elastic members 206 and 208 are formed on the upper surface and the lower surface, respectively.

On the other hand, the upper and lower yokes 202 and 204 are formed with contact portions 202b and 204b protruding from the internal space on both sides in the lateral direction, and the yokes 202 and 204 are formed at the contact portions 202b and 204b, respectively. Contact with a pair of elastic members 206, 208. These contact portions 202b and 204b are different from the first embodiment in that they are located on the central axis in the lateral direction and in the center in the longitudinal direction of the yokes 202 and 204, respectively. This point will also be described later.

[A pair of elastic members]
The pair of upper and lower elastic members 206 and 208 used in the second embodiment are formed by punching a thin plate-shaped spring member into a substantially angular ring shape and bending the short side portions on both sides thereof with respect to the long side portion. The four corner portions connecting the short side portion and the long side portion are curved portions 206c and 208c. The elastic members 206 and 208 are in contact with the upper and lower yokes 202 and 204 at two contact portions 202b and 204b, respectively, which is also different from the first embodiment. That is, the elastic members 206 and 208 are formed as facing portions 206a and 208a in which the central portion of the long side portion corresponding to the contact portions 202b and 204b has a leaf spring shape, respectively.

Further, in each of the elastic members 206 and 208, the short side portions on both sides are bent with respect to the long side portion as described above, so that the side edge (side surface in the thickness direction) in the bending direction faces the armature 220. I'm letting you. In each of the elastic members 206 and 208, the central portion of the short side portion is formed as the contact portion 206b and 208b. The elastic members 206 and 208 are in contact with the armature 220 at two points on both the upper and lower sides at the contact portions 206b and 208b formed in the center of the short side portion, and the contact portions on both sides of the upper elastic member 206. The 206b and the contact portions 220a on both sides on the upper surface of the armature 220 are in contact with each other, and the contact portions 208b on both sides of the lower elastic member 208 and the contact portions 220b on both sides on the lower surface of the armature 220 are in contact with each other. Contact. As described above, in the second embodiment, the contact relationship between the elastic members 206, 208 and the armature 220 is different from that in the first embodiment.

Further, also in the second embodiment, in the completed state of the electromechanical converter 200, the elastic members 206 and 208 are sandwiched between the upper and lower yokes 202 and 204 and the armature 220 with a predetermined displacement amount (deformation amount). .. As a result, the armature 220 is supported at a position where these forces are in equilibrium while receiving elastic forces (repulsive forces) of a pair of upper and lower elastic members 206 and 208, and an appropriate gap (air gap) is created between the armature 220 and the structural portion. Have and be placed. In the disassembled state of FIG. 8, the elastic members 206 and 208 are shown in a deformed state as in FIG. 7, but in the free state (no load), the facing portions 206a and 208a of the elastic members 206 and 208 are shown. Is a flat plate, and its long side is not bent and deformed.

Also in the second embodiment, soft magnetic materials such as permalloy of 45% Ni are used for the yokes 202 and 204 and the armature 220, and stainless steel materials such as SUS301 for springs are used for the elastic members 206 and 208. Used.

[Relationship with the central axis]
Next, the relationship with some central axes defined in the structural part of the electromechanical converter 200 in the second embodiment will be described. The point that the central axis is defined in, for example, three directions is the same as that of the first embodiment.

[Central axis A1]
FIG. 9 is a cross-sectional view of the electromechanical converter 200 along the IX-IX line in FIG. Assuming that the longitudinal direction of the structural portion seen in FIG. 7 is, for example, the horizontal direction, the cross section shown in FIG. 9 is the horizontal cross section (the XY axis direction cross section) of the electromechanical converter 200. Also in the second embodiment, the horizontal central axis A1 in the longitudinal direction can be defined in the structural portion of the electromechanical converter 200.

[Armature tilt (1)]
Similarly, in the second embodiment, it is structurally unlikely that the armature 220 is tilted in the arrow H direction (horizontal direction) in FIG. 9 with respect to the central axis A1. This is because the elastic members 206 and 208, which also support the armature 220, do not exert a force in the direction of arrow H between the elastic members 206 and 208 and the yokes 202 and 204, so that the force imbalance is unlikely to occur due to the structure. be.

FIG. 10 is a cross-sectional view of the electromechanical converter 200 along the XX line in FIG. 7. When FIG. 9 is a horizontal cross-sectional view, FIG. 10 is a vertical cross-sectional view (YZ axis direction cross-sectional view) in the lateral direction. As shown in FIG. 10, a horizontal central axis A2 in the lateral direction can be defined in the structural portion. The direction of the cross section is different from that of the first embodiment because the arrangement of the contact portions 202b and 204b having the cross section is different by 90 ° in the horizontal direction from the first embodiment. It can be seen that the members constituting the structural portion such as the yokes 202 and 204 and the coil 218 are all symmetrically arranged with the central axis A2 as a common one in the horizontal direction (YZ plane).

[Armature tilt (2)]
In the second embodiment, it is structurally unlikely that the armature 220 is tilted in the arrow V direction (vertical direction) in FIG. 10 with respect to the central axis A2, so this is not a problem.

[Central axis lines A1 and A3]
Next, FIGS. 11A and 11B are cross-sectional views of the electromechanical converter 200 at positions along the XI-XI line in FIG. When FIG. 10 is a vertical cross-sectional view in the lateral direction (YZ axis cross-sectional view), FIGS. 11A and 11B are longitudinal vertical cross-sectional views (XZ-axis direction cross-sectional view). Further, FIG. 11A is an overall cross-sectional view, and FIG. 11B is an enlarged partial cross-sectional view of the range surrounded by the alternate long and short dash line of FIG. 11A. As shown in FIG. 11A, the structural portion may be defined with a vertical central axis A3 as well as a horizontal central axis A1 in the lateral direction. The central axis A2 in the lateral direction (no reference numeral in FIGS. 11A and 11B) is located on the intersection of the central axis A1 and the central axis A3.

[Armature tilt (3)]
In the second embodiment, the inclination of the armature 220 in the arrow L direction (vertical direction) of FIG. 11A with respect to the central axis A1 can be a problem. The inclination of the armature 220 in the direction of the arrow L can be a problem for the central axis A3 as well, but as for the central axis A2, it is the inclination around the central axis A2 (rotational direction). Then, according to the knowledge obtained from the technical matters of Patent Document 3 mentioned as the prior art document, such an inclination becomes a problem mainly in the directions of the central axis A1 with the yokes 202 and 204 and the elastic members 206 and 208. It can be seen that there may be an imbalance in the forces acting between.

In the present invention, even when the armature 220 is supported by the pair of elastic members 206 and 208 as in the second embodiment, the yokes 202 and 204 and the elastic members are considered in view of the structural factors that cause the armature 220 to tilt. It realizes a structure that does not cause an imbalance in the force acting between 206 and 208. The structure is realized by a plurality of aspects listed below.

[First aspect]
FIG. 11A: The first aspect of this structure is a structure in which the contact portions 202b and 204b of the yokes 202 and 204 come into contact with the elastic members 206 and 208 on a curved surface. That is, assuming that the facing portions 206a and 208a are flat plates in a free state (not shown) of the elastic members 206 and 208, the contact portions 202b and 204b in contact with them are formed on a curved surface instead of a flat surface. Therefore, the contact region between the contact portions 202b and 204b and the facing portions 206a and 208a has a linear shape extending in the central axis A2 direction. As a result, the points of action of the forces F acting on the elastic members 206 and 208 from the contact portions 202b and 204b of the yokes 202 and 204 are substantially linearly narrowed and concentrated, so that the force F is concentrated in the direction of the central axis A1. The points of action of are not dispersed. Therefore, in the case of assuming the structure of the second embodiment, the width between the points of action of the force spreading in the central axis A1 direction, which is a problem in the prior art (Patent Document 3 and the like), is set to almost none (zero), as described above. The problem can be solved.

FIG. 11B: The curved surfaces formed on the contact portions 202b and 204b can be preferably defined by the following indexes. For example, taking the upper contact portion 202b as an example, the facing portion 206a is deformed due to bending in the deformed state of the elastic member 206, but the radius of curvature R1 appearing in the facing portion 206a in this bending state is higher than that of the radius of curvature R1. The radius of curvature R2 of the curved surface formed on the contact portion 202b is reduced (R1> R2). As a result, as described above, the contact region between the contact portion 202b on the yoke 202 side and the facing portion 206a of the elastic member 206 is narrowed linearly in the direction of the central axis A1, and the points of action of the force F are almost non-dispersed ( It is suppressed to zero).

Since the contact portions 202b and 204b of the yokes 202 and 204 are arranged vertically symmetrically with respect to the central axes A1 and A2 of the structural portion, the forces F received by the elastic members 206 and 208 from the upper and lower yokes 202 and 204. Does not stagger from the central axes A2 and A3, and the generation of torque that causes the tilt of the armature 220 in the direction of the arrow L shown in FIG. 11A can be suppressed to a very small value.

[Second aspect]
12A and 12B are views showing a second aspect of the structure at the same cross-sectional positions as FIGS. 11A and 11B. Of these, FIG. 12A is an overall cross-sectional view, and FIG. 12B is an enlarged partial cross-sectional view of the range surrounded by the alternate long and short dash line of FIG. 12A.

FIG. 12A: In the second aspect, contact portions 402b and 404b different from those in the first aspect are formed on the yokes 202 and 204, but the other aspects are the same as in the first aspect. In such a second aspect, the contact portions 402b and 404b are in contact with the elastic members 206 and 208 at the edges (edges). Similarly, assuming that the facing portions 206a and 208a are flat plates in a free state (not shown) of the elastic members 206 and 208, the contact portions 402b and 404b in contact with them are not planar and the facing portions 206a are not formed. , 208a is formed in a convex shape (mountain shape), and the contact portion thereof has an edge shape. Therefore, the contact region between the contact portions 402b and 404b and the facing portions 206a and 208a is also a straight line extending in the direction of the central axis A2 (no reference numeral in FIGS. 12A and 12B). As a result, the points of action of the forces F acting on the elastic members 206 and 208 from the contact portions 402b and 404b of the yokes 202 and 204 are substantially linearly narrowed and concentrated, so that the force F is concentrated in the direction of the central axis A1. The action points of the above are not dispersed, and the width between the action points of the force spreading in the central axis A1 direction is made almost zero (zero), so that the same problem as described above can be solved.

FIG. 12B: The edges formed in the contact portions 402b and 404b can be preferably defined by the following indexes. Similarly, for example, taking the upper contact portion 402b as an example, the facing portion 206a is deformed due to bending in the deformed state of the elastic member 206, but the contact region appearing in the facing portion 206a in this bending state. The opening angle θ2 of the edge formed on the contact portion 402b is made smaller than the opening angle θ1 centered on (θ1> θ2). As a result, as described above, the contact region between the contact portion 402b on the yoke 202 side and the facing portion 206a of the elastic member 206 is narrowed linearly in the direction of the central axis A1, and the points of action of the force F are almost non-dispersed ( It is suppressed to zero).

Since the contact portions 402b and 404b of the yokes 202 and 204 are arranged vertically symmetrically with respect to the central axes A1 and A2 of the structural portion, the forces F received by the elastic members 206 and 208 from the upper and lower yokes 202 and 204. Does not stagger from the central axes A2 and A3, and the generation of torque that causes the tilt of the armature 220 in the direction of the arrow L shown in FIG. 12A can be suppressed to a very small value.

According to the plurality of embodiments described above, the following advantages can be obtained.
By introducing the structures of the first and second aspects exemplified in the first embodiment, the armature 120 due to the imbalance of the force acting between the yokes 102 and 104 of the electromechanical converter 100 and the elastic members 106 and 108. It improves the inclination and solves the problem that the performance of the electromechanical converter 100 is adversely affected and the yield is deteriorated.
The above shows the structure composed of two pairs of elastic members 106, 108 as in the first embodiment, but according to the second embodiment, the structure composed of a pair of elastic members 206, 208. It can also be applied to cases. As a result, the inclination of the armature 220 due to the imbalance of the force acting between the yokes 202 and 204 of the electromechanical converter 200 and the pair of elastic members 206 and 208 is improved, which adversely affects the performance of the electromechanical converter 200. Solve the problem of poor yield.

The present invention can be variously modified and implemented without being restricted by the plurality of embodiments described above.

In the first embodiment, an example in which the facing portions 106a and 108a of the elastic members 106 and 108 are formed in a groove shape is given, but as in the second embodiment, the flat plate-shaped portions are formed on the facing portions 106a and 108a over the entire width. May be.

In each embodiment, there are no particular restrictions on the shape, size, and details of various members (magnets, yokes, coils, etc.) that make up the structural part, and they can be appropriately deformed or changed.

When the abutting portions 102b, 104b and the like have an edge shape, the opening angle θ2 may be an acute angle than in the example, and the edge is not a mere chevron but an edge with multiple angles. May be good.

Further, when the contact portions 102b, 104b and the like are curved surfaces, only the portions in contact with the facing portions 106a, 108a and the like may have a curved surface shape, and the non-contact portions may have a non-curved surface structure.

This application is based on Japanese Patent Application No. 2020-1572724 filed on September 11, 2020, the contents of which are incorporated herein by reference.

100 Electromechanical transducers 102, 104 Yoke 102b, 104b Contact parts 106, 108 Elastic members 106a, 108a Opposing parts 110, 112, 114, 116 Magnet 118 Coil 120 Armature

Claims (5)

1. A structural part having two pairs of magnets with different poles facing each other, a yoke that guides the magnetic flux generated by these magnets in a closed circuit shape, and a coil arranged in an internal space surrounded by the yokes.
   The armature is arranged in a pair between the armature arranged so as to penetrate the internal space of the structural portion in the winding center direction of the coil and the yoke with the armature interposed therebetween, and the armature is supported by the internal space. With elastic members
   An electromechanical transducer having a linear contact region with the elastic member and a contact portion for bringing the elastic member into contact with the yoke.
2. In the electromechanical transducer according to claim 1,
   The elastic member is
   It has a leaf spring-like facing portion that comes into contact with the abutting portion in a deformed state sandwiched between the armature and the yoke.
   The contact portion is
   An electromechanical converter characterized by having a curved surface having a radius of curvature smaller than the radius of curvature appearing at the facing portion in a deformed state of the elastic member.
3. In the electromechanical transducer according to claim 1,
   The elastic member is
   It has a leaf spring-like facing portion that comes into contact with the abutting portion in a deformed state sandwiched between the armature and the yoke.
   The contact portion is
   An electromechanical transducer characterized by having an edge having a convex shape with respect to the facing portion.
4. In the electromechanical transducer according to claim 3,
   The edge is
   An electromechanical transducer having an opening angle smaller than the opening angle centered on the contact region that appears in the facing portion in a deformed state of the elastic member.
5. In the electromechanical converter according to any one of claims 1 to 4.
   The contact portion is
   The contact area with the elastic member on an axis that is symmetrical with respect to the central axis of the structural portion along the penetrating direction of the armature or the central axis of the structural portion orthogonal to the penetrating direction and parallel to each other. An electromechanical converter characterized by the placement of.
   

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