JP2005176122A - Magnetostriction displacement amplifier, and magnetostriction actuator and magnetostriction vibrating apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetostriction displacement amplifier a displacement amplification factor of which can easily be enhanced wherein the tracking performance of an output displacement with respect to a displacement of a magnetostriction element can be enhanced. <P>SOLUTION: The magnetostriction displacement amplifier 14 is configured with: super magnetostriction members 34A, 34B; a nearly rod shaped super magnetostriction rod 24 whose one end is a fixed end; a drive coil 26 provided to surround the outer circumference of the super magnetostriction rod 24 and for applying a magnetic field to the super magnetostriction rod 24 in its axial direction L1; and a displacement amplifying mechanism 30 for amplifying the displacement of the super magnetostriction rod 24 in the axial direction L1. Then the displacement amplifying mechanism 30 is configured with: a first plate-shaped elastic member elastically deformable in the thickness direction in response to a displacement of the super magnetostriction rod 24 in the axial direction L1; a second plate-shaped elastic plat member 42 located at the other end 38B of a cylindrical member 38 and elastically deformable in the thickness direction; and a fluid 44 filled in a space enclosed by the cylindrical member 38 and the first and second elastic members 40, 42. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a magnetostrictive displacement amplifying device using a magnetostrictive member, a magnetostrictive actuator and a magnetostrictive vibration device using the same.

  2. Description of the Related Art Conventionally, a magnetostrictive displacement amplifying apparatus that amplifies and outputs a displacement of a magnetostrictive member is known.

  For example, a conventionally known magnetostrictive displacement amplifying apparatus 100 shown in FIG. 9 includes a displacement amplifying mechanism 103 connected to a substantially rod-shaped magnetostrictive element 102 (see Patent Document 1). The displacement amplifying mechanism 103 includes a small roller 105 pressed against a driving body 104 coupled to the magnetostrictive element 102 and a large roller 108 pressed against a driven body 107 coupled to the output shaft 106. And the large roller 108 are concentrically coupled.

  In the magnetostrictive displacement amplifying apparatus 100, the displacement of the magnetostrictive element 102 is amplified in proportion to the radius ratio between the small roller 105 and the large roller 108 and output from the output shaft 106.

  On the other hand, the magnetostrictive displacement amplifying device 150 shown in FIG. 10 includes a lever-type displacement enlarging mechanism 152 connected to a substantially rod-shaped magnetostrictive element 151 (see Patent Document 2). The lever-type displacement enlarging mechanism 152 is composed of a rod-like member supported at a fulcrum 153. One end of the magnetostrictive element 151 is disposed at the force point 154, and one end of the output shaft 156 is disposed at the action point 155. .

  In the magnetostrictive displacement amplifying apparatus 150, the displacement of the magnetostrictive element 151 is proportional to the ratio of the length from the force point 154 to the fulcrum 153 and the length from the fulcrum 153 to the action point 155 in the lever type displacement magnifying mechanism 152. Amplified and output from the output shaft 156.

Japanese Utility Model Publication No. 5-20497 JP-A-5-236595

  However, in order to increase the displacement amplification factor in these conventionally known magnetostrictive displacement amplifying apparatuses 100 and 150, the radius ratio between the small roller 105 and the large roller 108, the length between the force point 154 and the fulcrum 153, the fulcrum 153 and the action point. Since it is necessary to increase the length ratio between 155, the displacement amplifying mechanism 103 and the lever type displacement enlarging mechanism 152 are easily increased in size, and it is difficult to make the apparatus compact.

  Further, due to its structure, there is a limit to the improvement of the followability of the output shafts 106 and 156 with respect to the displacement of the magnetostrictive elements 102 and 151, and it is particularly unsuitable for a speaker driving device or the like that requires high followability.

  The present invention has been made to solve such problems, and can easily increase the amplification factor of the displacement while having a small and simple structure. An object of the present invention is to provide a magnetostrictive displacement amplifying device capable of improving the follow-up performance of an output displacement with respect to the magnetostrictive actuator, and a magnetostrictive actuator and a magnetostrictive vibration device using the same.

  The inventor of the present invention can increase the displacement amplification factor while having a small and simple structure, and can improve the followability of the output displacement with respect to the displacement of the magnetostrictive element. The present inventors have found a magnetostrictive actuator and a magnetostrictive vibration device using the same.

  That is, the above-described object can be achieved by the following present invention.

  (1) A substantially rod-shaped magnetostrictive rod having a magnetostrictive member, one end of which is fixed, and an outer periphery of the magnetostrictive rod. The magnetic field is applied in the axial direction of the magnetostrictive rod. And a displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod, one end of the displacement amplifying mechanism being disposed on the free end side of the magnetostrictive rod. And an approximately cylindrical member whose inner diameter on the other end side is smaller than the inner diameter on the one end side, and disposed on the one end side of the approximately cylindrical member, in accordance with the axial displacement of the magnetostrictive rod. A plate-like first elastic member elastically deformable in the thickness direction, a plate-like second elastic member disposed on the other end side of the cylindrical member and elastically deformable in the thickness direction, A fluid filled in a space sealed by a cylindrical member and the first and second elastic members; Magnetostrictive displacement amplification device characterized by comprising a.

  (2) The magnetostrictive displacement amplification according to (1), wherein the substantially cylindrical member in the displacement amplifying mechanism is formed of a substantially cylindrical rigid body having a small diameter from the one end side toward the other end side. apparatus.

  (3) The substantially cylindrical member in the displacement amplifying mechanism is bent so as to convert the displacement in the axial direction of the magnetostrictive rod into a displacement in a direction different from the axial direction, and is normal to the surface of the first elastic member. The magnetostrictive displacement amplifying device according to (1) or (2), wherein the normal line on the surface of the second elastic member is non-parallel.

  (4) The magnetostrictive displacement amplifying device according to any one of (1) to (3), further including a member that covers a radially outer peripheral surface of the substantially cylindrical member in the displacement amplifying mechanism.

  (5) A substantially rod-shaped magnetostrictive rod having a magnetostrictive member and having one end fixed, and an outer periphery of the magnetostrictive rod are disposed, and a magnetic field is applied in the axial direction of the magnetostrictive rod. And a displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod, one end of the displacement amplifying mechanism being disposed on the free end side of the magnetostrictive rod. And a cylinder having a through hole in which the inner diameter on the other end side is smaller than the inner diameter on the one end side, and disposed at both ends of the through hole in the cylinder, and is slidable in the through hole. A magnetostrictive displacement amplifying device comprising: a pair of pistons, and a fluid filled in a space sealed by the cylinder and the pair of pistons.

  (6) The through hole in the displacement amplifying mechanism is bent so as to convert an axial displacement of the magnetostrictive rod into a displacement in a direction different from the axial direction, and the axial direction of the first piston and the second piston The magnetostrictive displacement amplifying device according to (5), wherein the axial direction of the magnetostrictive displacement amplifier is not parallel.

  (7) The magnetostrictive displacement amplifying device according to any one of (1) to (6), wherein the magnetostrictive member is a giant magnetostrictive member made of a giant magnetostrictive element.

  (8) A magnetostrictive actuator using the magnetostrictive displacement amplifying device according to any one of (1) to (7).

  (9) A magnetostrictive vibration device using the magnetostrictive displacement amplifying device according to any one of (1) to (7).

  According to the magnetostrictive displacement amplifying device, the magnetostrictive actuator using the magnetostrictive displacement amplifying device according to the present invention, and the magnetostrictive vibrating device, the amplification factor of the displacement can be increased while having a small and simple structure. It has an excellent effect that the followability of the output displacement with respect to can be improved.

  The present invention includes a magnetostrictive member having a substantially rod-like magnetostrictive rod having one end fixed, and an outer periphery of the magnetostrictive rod. A magnetic field is applied in the axial direction of the magnetostrictive rod. And a displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod, one end of the displacement amplifying mechanism being disposed on the free end side of the magnetostrictive rod. And a substantially cylindrical member having a smaller inner diameter on the other end side than the inner diameter on the one end side, and disposed on the one end side of the substantially cylindrical member so as to be displaced in the axial direction of the magnetostrictive rod. Accordingly, a plate-like first elastic member elastically deformable in the thickness direction, a plate-like second elastic member disposed on the other end side of the cylindrical member and elastically deformable in the thickness direction, A flow filled in a space sealed by the cylindrical member and the first and second elastic members. When, by magnetostrictive displacement amplifying device comprising a, it is obtained by solving the above problems.

  The present invention also includes a magnetostrictive member having a magnetostrictive member and having a substantially rod-like magnetostrictive rod having one end fixed, and an outer periphery of the magnetostrictive rod, the axial direction of the magnetostrictive rod. A drive coil for applying a magnetic field, and a displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod, one end of the displacement amplifying mechanism on the free end side of the magnetostrictive rod. A cylinder having a through hole in which the inner diameter on the other end side is smaller than the inner diameter on the one end side, and disposed at both ends of the through hole in the cylinder, and inside the through hole A magnetostrictive displacement amplifying device having a pair of slidable pistons and a fluid filled in a space sealed by the cylinder and the pair of pistons solves the same problem as described above.

  Hereinafter, Embodiment 1 and Embodiment 2 of the present invention will be described in detail with reference to the drawings.

  As shown in FIGS. 1 and 2, the magnetostrictive vibration device 10 to which the magnetostrictive displacement amplifying device according to the first embodiment of the present invention is applied includes a substantially cylindrical casing 12. Amplifying signals such as audio signals input from the tip guide 13 side via the magnetostrictive displacement amplifying device 14, a plurality of dry batteries 16 that are driving sources of the magnetostrictive displacement amplifying device 14, and the jack 18, Amplifier circuits 20 that output to the magnetostrictive displacement amplifying device 14 are partitioned and accommodated by substantially disc-shaped partition walls 22A and 22B, respectively. The partition wall 22A disposed between the magnetostrictive displacement amplifying device 14 and the plurality of dry batteries 16 is formed of a soft magnetic member.

  2, the magnetostrictive displacement amplifying device 14 is disposed so as to surround a substantially rod-shaped super magnetostrictive rod 24 having one end 24A fixed to the partition wall 22A and the outer periphery of the super magnetostrictive rod 24. And a displacement amplification mechanism 30 for amplifying the displacement of the giant magnetostrictive rod 24 in the axial direction L1.

  In this example, the giant magnetostrictive rod 24 includes three substantially disc-shaped bias magnets 32A to 32C and two substantially cylindrical giant magnetostrictive members disposed so as to be sandwiched between the three bias magnets 32A to 32C. The bias magnets 32A to 32C and the giant magnetostrictive members 34A and 34B are bonded and integrated in the axial direction L1.

  The giant magnetostrictive members 34A and 34B use giant magnetostrictive elements as materials. Here, the “super magnetostrictive element” means a magnetostrictive element made of a powder sintered alloy or a single crystal alloy containing a rare earth element and / or a specific transition metal as a main component (for example, terbium, dysprosium, iron, etc.). It has the property of causing large displacement when a magnetic field is applied from the outside.

  The drive coil 26 has a structure capable of applying a magnetic field in the axial direction L1 to the giant magnetostrictive members 34A and 34B. The drive coil 26 is connected to the amplifier circuit 20, and the magnetic field of the drive coil 26 varies based on a signal input from the outside via the jack 18.

  The movable tip portion 28 includes a substantially disc-shaped flange portion 28A fixed to the bias magnet 32A of the giant magnetostrictive rod 24, and a rod portion 28B extending from the flange portion 28A along the axial direction L1 of the giant magnetostrictive rod 24. Is formed. Further, two springs 36A and 36B are contracted between the flange portion 28A of the movable tip portion 28 and the tip guide 13, and the movable tip portion 28 is biased toward the giant magnetostrictive rod 24 side. Further, the rod portion 28B of the movable tip portion 28 is in contact with the displacement amplification mechanism 30, and the vibration in the axial direction L1 of the giant magnetostrictive rod 24 can be transmitted to the displacement amplification mechanism 30 via the movable tip portion 28. It has become.

  As shown in FIG. 3, the displacement amplifying mechanism 30 includes a cylindrical member 38 in which the inner diameter R2 on the other end 38B side is smaller than the inner diameter R1 on the one end 38A side (R1> R2), and the cylindrical member 38. A plate-like first elastic member 40 that is disposed on one end side 38A and can be elastically deformed in the thickness direction in accordance with the displacement of the giant magnetostrictive rod 24 in the axial direction L1, and on the other end side 38B of the cylindrical member 38. A plate-like second elastic member 42 disposed and elastically deformable in the thickness direction, and a fluid 44 filled in a space sealed by the tubular member 38 and the first and second elastic members 40, 42. It is configured.

  Further, the cylindrical member 38 of the displacement amplifying mechanism 30 is covered with the distal end guide 13 on the outer peripheral surface in the radial direction, and deformation in the radial direction is restricted by the distal end guide 13.

  The cylindrical member 38 is formed of a cylindrical rigid body having a small diameter from the one end 38A side toward the other end 38B side, and a rigid body such as metal or plastic can be applied to the cylindrical member 38, for example. . Further, for example, elastic members such as rubber can be applied to the first and second elastic members 40 and 42 disposed at both ends of the cylindrical member 38.

  Next, the operation of the magnetostrictive vibration device 10 according to the first embodiment will be described.

  When a signal is input to the magnetostrictive vibration device 10 via the jack 18, the signal is amplified by the amplifier circuit 20 and then input to the drive coil 26 of the magnetostrictive displacement amplifier 14. Then, the drive coil 26 is driven by the amplified signal, and the coil magnetic field of the drive coil 26 changes. As a result, the giant magnetostrictive rod 24 is displaced (vibrated) in the axial direction L1 according to the signal. The displacement in the axial direction L1 is input to the displacement amplification mechanism 30 via the movable tip 28 and amplified by the displacement amplification mechanism 30.

  More specifically, as shown in FIG. 3, when the displacement in the axial direction L1 of the giant magnetostrictive rod 24 is transmitted by the movable tip 28, the first elastic member 40 of the displacement amplifying mechanism 30 is pressed, The first elastic member 40 is displaced by the maximum displacement amount X1 in the axial direction L1. As a result, the second elastic member 42 protrudes by the volume of the fluid 44 pushed out by the first elastic member 40, and is displaced by a maximum displacement amount X2 in the axial direction L1.

  The displacement amount X1 of the first elastic member 40 is amplified based on the ratio of the areas in the thickness direction of the first elastic member 40 and the second elastic member 42, but the cylindrical member 38 in the present invention. Since the inner diameter R2 on the other end 38B side is smaller than the inner diameter R1 on the one end 38A side, the area in the thickness direction of the second elastic member 42 is larger than the area in the thickness direction of the first elastic member 40. Is also getting smaller. Therefore, the displacement amount (output displacement amount) X2 of the second elastic member 42 is larger than the displacement amount (displacement amount of the giant magnetostrictive rod 24) X1 of the first elastic member 40.

  The displacement of the giant magnetostrictive rod 24 thus amplified is output to the outside via the second elastic member 42 of the displacement amplification mechanism 30.

  According to the magnetostriction displacement amplifying apparatus 14 according to the first embodiment of the present invention, the substantially magnetostrictive rod 24 having the giant magnetostrictive members 34A and 34B and having one end 24A as a fixed end, and the magnetostriction. A drive coil 26 for applying a magnetic field in the axial direction L1 of the giant magnetostrictive rod 24 and a displacement amplification mechanism for amplifying the displacement of the giant magnetostrictive rod 24 in the axial direction L1 are disposed so as to surround the outer periphery of the rod 24. The displacement amplification mechanism 30 has one end 38A disposed on the free end 24B side of the giant magnetostrictive rod 24, and an inner diameter R2 on the other end 38B side than an inner diameter R1 on the one end 38A side. A cylindrical member 38 having a small diameter, and a plate-like member disposed on one end side 38A of the cylindrical member 38 and elastically deformable in the thickness direction in accordance with the displacement of the giant magnetostrictive rod 24 in the axial direction L1. First elastic member 40 and cylindrical member 8, a plate-like second elastic member 42 that is elastically deformable in the thickness direction, and is sealed in a space sealed by the cylindrical member 38 and the first and second elastic members 40, 42. Therefore, the displacement of the first elastic member 40 and the second elastic member 42 can be reduced by changing the ratio of the area in the thickness direction of the first elastic member 40 and the second elastic member 42. The amplification factor can be easily increased. Further, since the displacement of the giant magnetostrictive rod 24 is transmitted by the fluid 44, the followability of the output displacement with respect to the displacement of the magnetostrictive member can be improved.

  In particular, since the cylindrical member 38 is formed of a substantially cylindrical rigid body having a small diameter from the one end 38A side to the other end 38B side, the displacement of the magnetostrictive member can be amplified more efficiently.

  In addition, since the distal end guide 13 that covers the radially outer peripheral surface of the cylindrical member 38 is provided, the distal end guide 13 can regulate the deformation of the cylindrical member 38 in the radial direction. High efficiency of displacement amplification is achieved.

  The magnetostrictive displacement amplifying apparatus according to the present invention is not limited to the structure and shape of the magnetostrictive displacement amplifying apparatus 10 according to the first embodiment. For example, the cylindrical member 38 in the displacement amplifying mechanism 30 has a rectangular shape. The member may have a cylindrical shape or the like, and may be any member that is rigid enough to transmit the displacement of the giant magnetostrictive rod 24 in the axial direction L1.

  Further, like the cylindrical member 52 in the displacement amplifying mechanism 50 shown in FIG. 4, the giant magnetostrictive rod 24 is bent so as to convert the displacement in the axial direction L1 into a displacement in a direction different from the axial direction L1. If the normal line L1 on the surface of the first elastic member 40 and the normal line L2 on the surface of the second elastic member 42 are made non-parallel, in addition to amplification of the displacement of the magnetostrictive member, the displacement direction is also converted. Can do.

  That is, a magnetostrictive displacement amplifying device according to the present invention includes a magnetostrictive member, and is disposed so as to surround a substantially rod-shaped magnetostrictive rod having one end fixed, and an outer periphery of the magnetostrictive rod, A driving coil for applying a magnetic field in the axial direction of the magnetostrictive rod; and a displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod. A cylindrical member disposed on the free end side of the rod and having a smaller diameter from the one end side toward the other end side, and disposed on the one end side of the substantially cylindrical member, and the axial direction of the magnetostrictive rod A plate-like first elastic member that can be elastically deformed in the thickness direction according to the displacement of the plate, and a plate-like second elasticity that is disposed on the other end side of the cylindrical member and can be elastically deformed in the thickness direction. A member, an empty space sealed by the cylindrical member and the first and second elastic members A fluid filled within, as long as it becomes a.

  Next, a magnetostrictive actuator AT1 to which the magnetostrictive displacement amplifying apparatus according to Embodiment 2 of the present invention is applied will be described.

  As shown in FIG. 5, the magnetostrictive actuator AT1 includes a magnetostrictive displacement amplifying device 60. The magnetostrictive displacement amplifying device 60 includes a substantially rod-shaped giant magnetostrictive rod 61 having one end 61A fixed to a casing 64, and The driving coil 66 is disposed so as to surround the outer periphery of the giant magnetostrictive rod 61, and a displacement amplifying mechanism 68 for amplifying the displacement of the giant magnetostrictive rod 61 in the axial direction L3. Since the drive coil 66 is the same as that of the magnetostrictive speaker SP1, description thereof is omitted.

  In this example, the giant magnetostrictive rod 61 includes two substantially disc-shaped bias magnets 62A and 62B, and a substantially cylindrical giant magnetostrictive member 63 disposed so as to be sandwiched between the two bias magnets 62A and 62B. The bias magnets 62A and 62B and the giant magnetostrictive member 63 are bonded and integrated in the axial direction L3.

  The displacement amplifying mechanism 68 is provided with a cylinder 72 having a through hole 70 and a pair of pistons 74 and 76 that are respectively disposed at both ends 70A and 70B of the through hole 70 in the cylinder 72 and are slidable in the through hole 70. And a fluid 78 filled in a space sealed by the cylinder 72 and the pair of pistons 74 and 76.

  The through hole 70 of the cylinder 72 has one end 70A disposed on the free end 61B side of the giant magnetostrictive rod 61, and an inner diameter R4 on the other end 70B side smaller than an inner diameter R3 on the one end 70A side (R3> R4). ).

  Next, the operation of the magnetostrictive actuator AT1 according to the second embodiment will be described.

  When a predetermined voltage is applied to the drive coil 66, the giant magnetostrictive rod 24 is displaced (elongated) in the axial direction L3 in accordance with the magnitude of the coil magnetic field of the drive coil 66. The displacement in the axial direction L3 is input to the first piston 74 and then transmitted to the second piston 76 via the fluid 78.

  The displacement amount X3 of the first piston 74 is amplified based on the ratio of the cross-sectional areas of the first piston 74 and the second piston 76. The through hole 70 in the present invention has an inner diameter on the one end 70A side. Since the inner diameter R4 on the other end 70B side is smaller than R3, the sectional area of the second piston 76 is smaller than the sectional area of the first piston 74. Accordingly, the displacement amount (output displacement amount) X4 of the second piston 76 is larger than the displacement amount (displacement amount of the giant magnetostrictive rod 61) X3 of the first piston 74.

  The amplified displacement of the giant magnetostrictive rod 61 is output to the outside via the second piston 76 of the displacement amplification mechanism 68.

  The inventors of the present invention also collected data on the relationship between the magnitude of the voltage applied to the drive coil 66 and the displacement amounts of the first and second pistons 74 and 76. In this experiment, a cylindrical member having a diameter of 7.4 mm and a length of 20 mm is applied as the giant magnetostrictive member 63, and the drive coil 66 has a line type AWG, a diameter of 8 mm, a length of 20 mm, and a winding number of 2000 turns. It was. Further, the supply voltage to the drive coil 66 was 0 to 120 V, and a 1 KHz pulse magnetic field was applied to the drive coil 66. The first piston 74 has a diameter of 10 mm and a length of 10 mm, and the second piston 76 has a diameter of 3.2 mm and a length of 10 mm.

  As a result, as shown in FIG. 6, the output displacement amount (displacement amount of the second piston 76) X4 of the magnetostrictive actuator AT1 is the displacement amount of the giant magnetostrictive rod 61 (the displacement amount of the giant magnetostrictive rod 61) in the voltage range of 10 to 120V collected data. It was found that the first piston 74 was amplified to about 10 times the displacement (X3).

  As described above, the magnetostrictive displacement amplifying apparatus 60 according to the second embodiment of the present invention can achieve the same effects as the magnetostrictive displacement amplifying apparatus 14 according to the first embodiment.

  Further, the magnetostrictive actuator AT1 can solve the conventional problem that a low-frequency sound pressure cannot be obtained sufficiently.

  Specifically, since the sound pressure of sound is determined by the amplitude and frequency of the diaphragm, in order to obtain the same sound pressure, an amplitude larger than the amplitude of the high frequency is required at a low frequency. In general, in a magnetostrictive actuator, since the dimensional change of the magnetostrictive member is determined by the strength of the applied magnetic field, the dimensional change occurs based on the magnetic field strength depending on the magnitude of each frequency component, which is determined by the magnitude of the audio frequency component. . For example, when the magnetostrictive actuator is applied to a plate-like speaker, the low-frequency amplitude causes vibration with an amplitude determined by the frequency component of the electric signal, so that only a low sound pressure can be obtained compared to the high frequency. According to the magnetostrictive actuator AT1 according to the second embodiment, a large vibration can be transmitted to the diaphragm, and a low-frequency sound pressure can be obtained at the same level as a high-frequency sound pressure.

  The magnetostrictive displacement amplifying apparatus according to the present invention is not limited to the structure and shape of the magnetostrictive displacement amplifying apparatus 60 according to the second embodiment. For example, the displacement amplifying mechanism of the magnetostrictive actuator AT2 shown in FIG. As shown in FIG. 80, the magnetostrictive rod 61 has a through-hole 82 bent so as to convert the displacement in the axial direction L3 of the giant magnetostrictive rod 61 into a displacement in the direction L4 different from the axial direction L3. If the axial direction L4 of the two pistons is made non-parallel, the effect of the magnetostrictive actuator AT1 can be obtained and the displacement direction can also be converted.

  The inventors of the present invention also collected data on the relationship between the magnitude of the voltage applied to the drive coil 66 and the displacement amounts of the first and second pistons 74 and 76 for the magnetostrictive actuator AT2. In this experiment, a cylindrical member having a diameter of 3 mm and a length of 16 mm is applied as the giant magnetostrictive member 63, and the drive coil 66 has a line type AWG, a diameter of 4 mm, a length of 16 mm, and a winding number of 1000 turns. . Further, the supply voltage to the drive coil 66 was 0 to 5 V, and a 1 KHz pulse magnetic field was applied to the drive coil 66. The first piston 74 has a diameter of 5 mm and a length of 10 mm, and the second piston 76 has a diameter of 3.2 mm and a length of 10 mm.

  As a result, as shown in FIG. 8, the output displacement amount (displacement amount of the second piston 76) X6 of the magnetostrictive actuator AT2 is within the displacement amount ( It was found that the first piston 74 was amplified to about 2.5 times the displacement amount (X5).

  In the magnetostriction displacement amplifying apparatus 60 according to the second embodiment, the first piston 74 is directly fixed to the giant magnetostrictive rod 61 in order to make the apparatus compact. However, the present invention is not limited to this. Instead, a displacement transmission member such as the movable tip 28 in the first embodiment may be interposed between the giant magnetostrictive rod 61 and the first piston 74.

  That is, a magnetostrictive displacement amplifying device according to the present invention includes a magnetostrictive member, and is disposed so as to surround a substantially rod-shaped magnetostrictive rod having one end fixed, and an outer periphery of the magnetostrictive rod, A driving coil for applying a magnetic field in the axial direction of the magnetostrictive rod; and a displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod. A cylinder having a through hole disposed on the free end side of the rod and having a smaller inner diameter on the other end side than the inner diameter on the one end side, and disposed on both ends of the through hole in the cylinder; and What is necessary is just to have a pair of pistons slidable in the through hole and a fluid filled in a space sealed by the cylinder and the pair of pistons.

  If it is not necessary to increase the displacement of the magnetostrictive displacement amplifying devices 14 and 60 according to the first and second embodiments, a magnetostrictive member made of a magnetostrictive element may be used instead of the super magnetostrictive member. Good.

1 is a schematic sectional side view showing a magnetostrictive vibration device to which a magnetostrictive displacement amplifying device according to Embodiment 1 of the present invention is applied. FIG. 1 is an enlarged schematic partial view showing the periphery of the magnetostrictive displacement amplifying apparatus in FIG. 1 is a schematic side sectional view showing a displacement amplification mechanism in FIG. Schematic side sectional view showing another example of the displacement amplification mechanism in FIG. Schematic side sectional view showing a magnetostrictive actuator to which a magnetostrictive displacement amplifying apparatus according to Embodiment 2 of the present invention is applied. A table showing the relationship between the magnitude of the voltage applied to the drive coil of the magnetostrictive actuator in FIG. 5 and the displacement amount of the first and second pistons. Schematic side sectional view showing another example of the magnetostrictive actuator in FIG. A table showing the relationship between the magnitude of the voltage applied to the drive coil of the magnetostrictive actuator in FIG. 7 and the displacement amount of the first and second pistons. Schematic side sectional view showing a conventional magnetostrictive displacement amplifier Schematic side sectional view showing another conventional magnetostrictive displacement amplifying apparatus

Explanation of symbols

L1 to L4 ... axial direction R1 to R6 ... inner diameter X1 to X6 ... displacement AT1, AT2 ... magnetostrictive actuator 10, 60 ... magnetostrictive vibration device 12, 64 ... casing 13 ... tip guides 14, 100, 150 ... magnetostrictive displacement amplifying device 16 ... dry cell 18 ... jack 20 ... amplifier circuit 22A, 22B ... partition wall 24, 61 ... giant magnetostrictive rod 26, 66 ... drive coil 28A ... flange part 28B ... rod part 30, 50, 68, 80, 103 ... displacement amplification mechanism 32A, 32B, 32C, 62A, 62B: bias magnets 34A, 34B, 63 ... giant magnetostrictive members 36A, 36B ... springs 38, 52 ... cylindrical members 40 ... first elastic members 42 ... second elastic members 44, 78 ... fluid 70, 82 ... Through-hole 72 ... Cylinder 74 ... 1st piston 76 ... 2nd piston 102, 151 ... Magnetostrictive element 104 ... Elements 105 ... small rollers 106,156 ... output shaft 107 ... driven member 108 ... large roller 152 ... lever-type displacement magnifying mechanism 153 ... supporting point 154 ... power point 155 ... action point

Claims (9)

  A substantially rod-shaped magnetostrictive rod having a magnetostrictive member and having one end fixed; and an outer periphery of the magnetostrictive rod, and for applying a magnetic field in the axial direction of the magnetostrictive rod A displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod, the displacement amplifying mechanism having one end disposed on the free end side of the magnetostrictive rod, and A substantially cylindrical member having a smaller inner diameter on the other end side than an inner diameter on the one end side, and a thickness corresponding to the axial displacement of the magnetostrictive rod disposed on the one end side of the substantially cylindrical member. A plate-like first elastic member that is elastically deformable in the direction, a plate-like second elastic member that is disposed on the other end side of the cylindrical member and is elastically deformable in the thickness direction, and the cylindrical member And a fluid filled in a space sealed by the first and second elastic members. Magnetostrictive displacement amplification device characterized by comprising Te. In claim 1,
The magnetostrictive displacement amplifying apparatus according to claim 1, wherein the substantially cylindrical member in the displacement amplifying mechanism is formed of a substantially cylindrical rigid body having a small diameter from the one end side toward the other end side. In claim 1 or 2,
The substantially cylindrical member in the displacement amplifying mechanism is bent so as to convert displacement in the axial direction of the magnetostrictive rod into displacement in a direction different from the axial direction, and the normal line on the surface of the first elastic member and the first 2. A magnetostrictive displacement amplifying device, wherein the normal line on the surface of the elastic member is non-parallel. In any one of Claims 1 thru | or 3,
A magnetostrictive displacement amplifying apparatus comprising a member that covers a radially outer peripheral surface of the substantially cylindrical member in the displacement amplifying mechanism.   A substantially rod-shaped magnetostrictive rod having a magnetostrictive member and having one end fixed; and an outer periphery of the magnetostrictive rod, and for applying a magnetic field in the axial direction of the magnetostrictive rod A displacement amplifying mechanism for amplifying the axial displacement of the magnetostrictive rod, the displacement amplifying mechanism having one end disposed on the free end side of the magnetostrictive rod, and A cylinder having a through hole whose inner diameter on the other end side is smaller than the inner diameter on the one end side, and a pair of slidable members disposed in both ends of the through hole in the cylinder and slidable in the through hole A magnetostrictive displacement amplifying device comprising: a piston; and a fluid filled in a space sealed by the cylinder and the pair of pistons. In claim 5,
The through hole in the displacement amplifying mechanism is bent so as to convert an axial displacement of the magnetostrictive rod into a displacement in a direction different from the axial direction, and the axial direction of the first piston and the axial direction of the second piston And a non-parallel magnetostrictive displacement amplifying device. In any one of Claims 1 thru | or 6.
The magnetostrictive displacement amplifying apparatus, wherein the magnetostrictive member is a super magnetostrictive member made of a super magnetostrictive element.   A magnetostrictive actuator using the magnetostrictive displacement amplifying device according to claim 1.   A magnetostrictive vibration device using the magnetostrictive displacement amplifying device according to claim 1.

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