JP6422740B2 - Inverse magnetostrictive vibration velocity sensor and measurement method using the same - Google Patents

Description

  The present invention relates to a vibration speed sensor using a magnetostrictive element. The present invention relates to an inverse magnetostrictive vibration velocity sensor capable of measuring vibration in a stable state even at a change from extremely low temperature to high temperature, and a measurement method using the same.

  Currently, various sources such as natural gas, methane gas or hydrogen are used as energy sources. Liquefaction is effective for refining and transporting, and it is easy to use as an energy source. Rotating equipment such as compressors plays an important role in the purification and transportation process. Vibration measurement, which is a major component of state monitoring for the purpose of maintaining these devices, is also important for the purpose of maintaining life and property. A vibration sensor is used for this vibration measurement.

  As a conventional vibration sensor for measuring a vibration speed, an electrodynamic vibration sensor mainly using a law of electromagnetic induction is mainly used. As shown in the schematic explanatory diagram of FIG. 12, the vibration speed sensor 51 is an electrodynamic type and uses the law of electromagnetic induction. This vibration speed sensor 51 supports a bar magnet 53 in a case 52 so as to be sandwiched by a fixing portion 54, and supports a solenoid coil 55 around the bar magnet 53 by a spring 56 or the like so as to be movable up and down. The solenoid coil 55 supported so as to freely move up and down serves as a movable portion 57. This is a sensor that detects an electromotive voltage induced in the solenoid coil 55 as a vibration speed by the relative speed between the solenoid coil 55 of the movable portion 57 and the bar magnet 53.

  Various techniques relating to vibration sensors using magnetostrictive elements have been proposed. For example, as disclosed in Japanese Patent Laid-Open No. 2006-214995, “Vibration Sensor” of Patent Document 1, a pair of bias magnets fixed to a fixed portion, and a first giant magnetostrictive element each cantilevered by the pair of bias magnets And a second giant magnetostrictive element, an inertial mass portion supported by the first giant magnetostrictive element and the second giant magnetostrictive element, a first pickup coil, and a second pickup coil. The vibration sensor comprised by these is proposed.

JP 2006-214995 A

  The conventional vertically mounted vibration speed sensor 51 as shown in FIG. 12 needs to have a self-resonant frequency of ¼ or less of the frequency used. For this reason, when the amount of bending of the spring 56 or the like increases, the stability of the elastic coefficient of the spring, long-term reliability at extremely low temperatures and high temperatures, and changes in the characteristics of the magnet may directly affect the generated voltage. As a result, there is a possibility that the vibration speed sensor 51 having such a configuration cannot be used in an extremely low temperature / high temperature place. As a result, the vibration speed sensor 51 having such a configuration has a problem that it cannot be used in a place where the temperature is extremely low or high.

  The inventor of the present invention uses a member of a magnetostrictive element having a simple shape instead of a spring in a vibration speed sensor, so that a magnetic bridge is obtained by utilizing the inverse magnetostrictive effect of the spring itself, that is, the magnetostrictive element. We focused on the fact that it can respond to changes in high temperature.

  The present invention has been developed to solve such problems. That is, the object of the present invention is to change from extremely low temperature to high temperature by using the inverse magnetostriction effect of the magnetostrictive element member having a simple shape without using a complicated spring structure and by forming a magnetic bridge. Is to provide an inverse magnetostrictive vibration velocity sensor capable of performing vibration measurement that is compatible with high-accuracy and stable environmental resistance, and a measurement method using the same.

  The speed sensor of the present invention is an inverse magnetostrictive vibration speed sensor (1, 21) that measures the vibration speed by the inverse magnetostrictive effect of the magnetostrictive element, and includes a magnetostriction detection coil (3) in which a column portion (2) is inserted. A weight part (5) having a magnet (4), a first magnetostrictive spring material (6) comprising a magnetostrictive element connecting one side of the support post part (2) and one side of the weight part (5); A second magnetostrictive spring material (7) composed of a magnetostrictive element connecting the other side of the support column (2) and the other side of the weight unit (5), and the support column (2) and the magnet (4) A magnetic bridge is formed as a closed magnetic path by the weight portion (5), the first magnetostrictive spring material (6), and the second magnetostrictive spring material (7), and the first magnetostrictive spring material (6) Inclining the second magnetostrictive spring material (7) in opposite directions between the column (2) and the weight (5) arranged in parallel. As a result, the tensile force generated by the vertical vibration of the column portion (2) and the weight portion (5) is applied to the first magnetostrictive spring material (6) or the second magnetostrictive spring material (7), and the compressive force is applied to the second. A change in permeability due to the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) is added to the magnetostrictive spring material (7) or the first magnetostrictive spring material (6), respectively. The magnetostriction detection coil (3) is used for detection and the vibration speed can be measured by the induced electromotive voltage.

  Alternatively, the speed sensor of the present invention is an inverse magnetostrictive vibration speed sensor (31, 41) that measures the vibration speed by the inverse magnetostrictive effect of the magnetostrictive element, and the column portion (2) having the magnet (32) is inserted. The first magnetostrictive spring material (6) comprising a magnetostrictive element (6), a weight portion (5), and a magnetostrictive element connecting one side of the support column portion (2) and one side of the weight portion (5). ), And a second magnetostrictive spring material (7) composed of a magnetostrictive element connecting the other side of the column part (2) and the other side of the weight part (5), the column part (2), The weight portion (5), the first magnetostrictive spring material (6), the second magnetostrictive spring material (7), and the magnet (32) form a magnetic bridge as a closed magnetic path, and the first magnetostrictive spring material (6). And the second magnetostrictive spring material (7) in a direction opposite to each other between the column (2) and the weight (5) arranged in parallel. By pulling it obliquely, the tensile force generated by the vertical vibration of the support column (2) and the weight (5) is compressed to the first magnetostrictive spring material (6) or the second magnetostrictive spring material (7). A force is applied to the second magnetostrictive spring material (7) or the first magnetostrictive spring material (6), respectively, due to the inverse magnetostrictive effect of the magnetostrictive elements of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7). A change in magnetic permeability is detected by the magnetostriction detection coil (3), and a vibration speed can be measured by an induced electromotive voltage.

For example, the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are both plate-like members having flexibility. The first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are both oval ring-shaped members. Both the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) can be magnetostrictive elements made of an iron-cobalt alloy.
The magnetostriction detection coil (3) is divided into a first magnetostriction detection coil (3a) and a second magnetostriction detection coil (3b) wound in the opposite direction to the first magnetostriction detection coil (3a). It is a magnetostriction detection coil.

The measuring method of the present invention includes a magnetostriction detection coil (3), a magnet (4, 32), a weight (5), one side of the support (2) and the weight ( 5) A first magnetostrictive spring material (6) composed of a magnetostrictive element connected to one side, and a magnetostrictive element connected to the other side of the column part (2) and the other side of the weight part (5). The magnetostrictive elements of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) in the inverse magnetostrictive vibration velocity sensor (1, 21, 31, 41) having the second magnetostrictive spring material (7). A method of detecting a change in magnetic permeability due to an inverse magnetostriction effect by a magnetostriction detection coil (3) and measuring a vibration speed by an induced electromotive voltage, wherein the weight (5), the magnets (4, 32), the first A magnetic bridge is formed as a closed magnetic path by the one magnetostrictive spring material (6), the second magnetostrictive spring material (7), and the support column (2), and the first magnetostrictive spring material ( ) And the second magnetostrictive spring material (7) are spanned between the supporting column (2) and the weight (5) arranged in parallel so as to incline in opposite directions. (2) When the tensile force generated by the vertical vibration of the weight portion (5) is applied to the first magnetostrictive spring material (6), a compressive force is applied to the second magnetostrictive spring material (7). When applied to the first magnetostrictive spring material (6), the tensile force is applied to the second magnetostrictive spring material (7). It is characterized by being measured by doubling.
The magnetostriction detection coil (3) is divided into a first magnetostriction detection coil (3a) and a second magnetostriction detection coil (3b) in which the first magnetostriction detection coil (3a) is wound in the opposite direction. A magnetostrictive detection coil can be used.

In the configuration of the present invention, a change in permeability due to the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) is detected by the magnetostriction detection coil (3), and the induced electromotive force is used. The vibration speed can be measured. Since the present invention does not use a spring having a complicated structure as in the prior art, it can cope with a change from an extremely low temperature to a high temperature.
In the present invention, since the rate of change in permeability with respect to the applied magnetic field is constant with respect to temperature change, the temperature characteristics are improved and the measurement accuracy of the vibration speed sensor is increased.

  Furthermore, the present invention does not use a spring having a complicated structure, the shapes of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are simple, easy to assemble, and variations in sensor sensitivity. Get smaller.

  According to the present invention, the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are inclined in directions opposite to each other between the column portion (2) and the weight portion (5) arranged in parallel. It is attached to the trapezoidal structure as a whole. Accordingly, the present invention contemplates that when the column portion (2) or the weight portion (5) vertically vibrates, when a tensile force is applied to the first magnetostrictive spring material (6), conversely, the second magnetostrictive spring material (7). A compressive force is applied to. In the present invention, when a compressive force is applied to the first magnetostrictive spring material (6), a tensile force is applied to the second magnetostrictive spring material (7). As a result, the first magnetostriction detection coil (3a) and the second magnetostriction detection coil (3b) can double the amount of change in permeability due to the inverse magnetostriction effect of the magnetostrictive element, and increase the measured output value. Can do.

1 is a schematic front view showing an inverse magnetostrictive vibration speed sensor of Example 1. FIG. 1 is a schematic plan view showing an inverse magnetostrictive vibration speed sensor of Example 1. FIG. 1 is a principle explanatory diagram of an inverse magnetostrictive vibration speed sensor of Example 1. FIG. It is a graph which shows the relationship between the magnetic permeability and bias magnetic flux density explaining the measurement principle of this invention. It is explanatory drawing of the vibration operation | movement of the inverse magnetostrictive vibration speed sensor of this invention, (a) is the state which the weight part is moving below, (b) is the state where the weight part is moving upward. It is sectional drawing which shows the state which mounted the reverse magnetostriction type | mold vibration speed sensor of this invention in the case. It is a graph which shows the vibration test result measured with the inverse magnetostrictive vibration speed sensor of this invention. It is a graph which shows the vibration test result measured with the inverse magnetostrictive vibration speed sensor of this invention. It is a schematic explanatory drawing which shows the inverse magnetostrictive vibration speed sensor of Example 2. FIG. 6 is a schematic explanatory view showing an inverse magnetostrictive vibration speed sensor of Example 3. FIG. 6 is a schematic explanatory view showing an inverse magnetostrictive vibration speed sensor of Example 4. It is a schematic explanatory drawing which shows the conventional electrodynamic vibration sensor.

  The present invention relates to an inverse magnetostrictive vibration speed sensor that forms a magnetic bridge as a closed magnetic path by a weight part, a magnet, two magnetostrictive spring materials, and a support part, and measures the vibration speed by the inverse magnetostrictive effect of the magnetostrictive element of the magnetostrictive spring material. It is.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Configuration of vibration speed sensor>
FIG. 1 is a schematic front view showing an inverse magnetostrictive vibration speed sensor according to a first embodiment. FIG. 2 is a schematic plan view showing the inverse magnetostrictive vibration velocity sensor of the first embodiment. FIG. 3 is a diagram illustrating the principle of the inverse magnetostrictive vibration speed sensor of the first embodiment.
The inverse magnetostrictive vibration speed sensor 1 according to the first embodiment includes a magnetostriction detection coil 3 in which a support column 2 is inserted, a weight unit 5 formed so as to sandwich a magnet 4, one end side of the support column unit 2, and a weight unit 5. A first magnetostrictive spring material 6 composed of a magnetostrictive element connected to one end side of the second magnetostrictive spring material, a second magnetostrictive spring material 7 composed of a magnetostrictive element connected to the other end side of the column portion 2 and the other end side of the weight portion 5; Consists of Here, the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 are described for the purpose of distinguishing the members having the same configuration, and these numbers do not indicate the order or the grade.
In the illustrated example of FIG. 1, a state in which the magnetostriction detection coil 3 is wound around the support 2 in two places is shown, but the present invention is not limited to this state.

The column portion 2 is a member for transmitting external vibration to the magnetostrictive elements (the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7). The support | pillar part 2 is a metal column-shaped columnar member, for example. A magnetostriction detection coil 3 is wound around the periphery.
In the magnetostriction detection coil 3, the magnetostrictive elements (the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7) are distorted by external vibration, and at this time, the permeability changes due to the inverse magnetostrictive effect of the magnetostrictive element. This is a member that detects a change in magnetic flux generated thereby by converting it into an electrical signal.
The magnetostriction detection coil 3 is divided into a first magnetostriction detection coil 3a adjacent to the first magnetostriction spring 6 and a second magnetostriction detection coil 3b adjacent to the second a magnetostriction spring 7, and the coils are relatively opposite to each other. It is rolled up.
The magnet 4 is made of a permanent magnet and is a member for applying a bias magnetic flux density to the magnetostrictive elements (the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7).

  The first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 made of magnetostrictive elements are spring materials (elements) for changing a change in strain due to external vibration to a change in magnetic flux. A change in permeability due to the inverse magnetostriction effect of the magnetostrictive element is detected by the magnetostriction detection coil 3. Based on this detection, the vibration speed is measured by the induced electromotive voltage. In the present invention, the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 are thin plate members having flexibility, and are configured in a simple shape. Since it is not a spring having a complicated structure as in the prior art, it can cope with a change from extremely low temperature to high temperature.

  Further, the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 are oval ring-shaped members as shown in the plan view of FIG. 2 in order to accurately detect the vibration of the column portion 2 or the weight portion 5. I made it. In this way, the two magnetostrictive element pieces are formed in an oval ring shape that connects the support column 2 and the weight unit 5, and the support column unit 2 or the weight unit 5 is provided at the diagonal position of the long side. Connected. That is, the column part 2 and the weight part 5 are respectively connected by two magnetostrictive element pieces on one side. The first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 in the shape of an oval ring can be stably detected. In addition, if it is the structure which connects the support | pillar part 2 and the weight part 5, it is not limited to the oval ring shape of the example of illustration, It can be set as a circular ring shape, a rectangular ring shape, or another shape.

  The first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 having such a configuration have a constant rate of change in permeability with respect to the applied magnetic flux density, so that the temperature characteristics are improved, and the vibration speed sensor Measurement accuracy increases.

<Magnetostrictive element>
In the present invention, an iron / cobalt alloy (Fe—Co magnetic material) is used as the magnetostrictive element constituting the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7. This is because this material is stable even in the extremely low to high temperature range. The element is not limited to this iron / cobalt alloy as long as the element has a property (magnetostriction) that causes a minute dimensional change when magnetized by a ferromagnetic material. For example, nickel materials, ferrite materials, Fe—Si magnetic materials, Fe—Ni magnetic materials (permalloy), and amorphous magnetic materials can be used.

<Description of measurement principle>
FIG. 4 is a graph showing the relationship between the magnetic permeability and the bias magnetic flux density for explaining the measurement principle of the present invention.
In the inverse magnetostrictive vibration speed sensor 1, a weight bridge 5, a magnet 4, a first magnetostrictive spring material 6, a second magnetostrictive spring material 7, and a support column 2 form a magnetic bridge as a closed magnetic path. A tensile force or a compressive force is generated in the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 due to the vertical vibration of the column portion 2 or the weight portion 5 due to external vibration. This tensile force or compressive force changes the permeability (magnetoresistance) by the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7. As a result, when the magnetic equilibrium point moves, an electric signal that generates a voltage proportional to the vibration speed between the magnetostriction detection coils 3 (the first magnetostriction detection coil 3a and the second magnetostriction detection coil 3b) is converted by a change in magnetic flux. Thus, the vibration speed can be measured.

<Description of vibration operation>
5A and 5B are explanatory views of the vibration operation of the inverse magnetostrictive vibration speed sensor of the present invention. FIG. 5A is a state where the weight portion is moving downward, and FIG. 5B is a state where the weight portion is moving upward. It is.
In the inverse magnetostrictive vibration speed sensor 1 of the first embodiment, the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 are inclined in opposite directions between the support column portion 2 and the weight portion 5 that are arranged substantially in parallel. It becomes a trapezoidal structure that spans over. In the trapezoidal structure, the longitudinal line of the support column 2 and the longitudinal line of the weight unit 5 are arranged in parallel, and each of the two magnetostrictive spring materials 6 that connect the support column 2 and the weight unit 5 are connected. , 7 means a configuration in a non-parallel state.

  As described above, the two magnetostrictive spring members 6 and 7 are arranged so as to have a trapezoidal structure as a whole. In the present invention, the weight portion 5 is supported by a spring or the like as an elastic member as in the prior art. Absent. This is because, if two magnetostrictive spring members are simply connected in parallel, the rectangular structure easily deforms into a parallelogram even with weak vibrations, so that accurate detection is difficult. If it arrange | positions so that it may become a trapezoid structure like this invention, it will not deform | transform into a parallelogram by vibration, but the change by the distortion of the magnetostrictive spring materials 6 and 7 can be detected.

  Further, the inverse magnetostrictive vibration speed sensor 1 of the first embodiment has a trapezoidal structure in which the side length of the support column 2 is longer than the side length on the weight unit 5 side. The two magnetostrictive spring members 6 and 7 are arranged in a trapezoidal shape as a whole because the tensile force generated by the vertical vibration of the support column 2 or the weight portion 5 is applied to the first magnetostrictive spring material 6. This is because Conversely, a compressive force is applied to the second magnetostrictive spring material 7, or a tensile force is applied to the second magnetostrictive spring material 7, and conversely, a compressive force is applied to the first magnetostrictive spring material 6. As a result, in the magnetostriction detection coil 3, the amount of change in magnetic permeability due to the inverse magnetostriction effect of the magnetostrictive element can be doubled, and the measured output value can be increased.

<Configuration with vibration speed sensor in the case>
FIG. 6 is a sectional view showing a state in which the inverse magnetostrictive vibration speed sensor of the present invention is housed in a case.
The inverse magnetostrictive vibration speed sensor 1 of the present invention is used by being mounted in a device in which a cylindrical case body 11 and circular lid bodies 12 are detachably attached on both sides. The case body 11 uses a magnetic shield. This magnetic shield protects the external magnetic field noise from being radiated into the vibration speed sensor 1. Further, the components and members inside the vibration speed sensor 1 are also mechanically protected.

  A connector 13 is attached to one lid 12. The connector 13 is a member for outputting an electrical signal generated by the magnetostrictive effect. A stud 14 is attached to the other lid 12. The stud 14 is a member for fixing the vibration speed sensor 1 to the object to be measured 58 (see FIG. 12).

  Stoppers 15 are provided at the top and bottom of the case body 11. The upper and lower stoppers 15 are members for preventing the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 from being broken or damaged when the weight portion 5 moves up and down due to an impact. For example, the stopper 15 is made of a synthetic resin material and does not move the upper and lower ends of the weight portion 5 beyond a predetermined distance.

<Frequency excitation test>
FIG. 7 is a graph showing the results of a frequency excitation test using the inverse magnetostrictive vibration velocity sensor of the present invention.
As an example, a frequency excitation test was performed using the inverse magnetostrictive vibration velocity sensor 1 having the resonance frequency fn = 35 Hz according to Example 1 of the present invention. In the inverse magnetostrictive vibration velocity sensor 1 as shown in FIG. 1, the frequency excitation test is performed in a state where the signals of the upper magnetostriction detection coil 3 and the lower magnetostriction detection coil 3 are connected in the same phase and added. did. The excitation force v = 20 mm / s was constant, and the half amplitude of the sensor output when the excitation frequency was applied from 50 Hz to 1000 Hz was measured under the condition that the bias magnetic flux density was 40 mT magnet.

<Vibration measurement test>
FIG. 8 is a graph showing the vibration test results measured by the inverse magnetostrictive vibration velocity sensor of the present invention.
Using the inverse magnetostrictive vibration speed sensor 1 of the present invention, a bearing abnormal vibration waveform in a rotation tester using a rolling bearing having a scratch on the outer ring was tested. The result of measuring the vibration is shown in FIG. The upper part of the graph shows the pulse signal waveform from the eddy current displacement sensor. A signal waveform of 1 pulse appears per rotation. This is the rotation reference signal. The middle waveform shows the vibration waveform measured using the inverse magnetostrictive vibration velocity sensor 1 of the present invention. Incidentally, this vibration waveform is a waveform that is multiplied by 20 with an amplifier and processed with a 5 kHz low-pass filter. The lower row shows the vibration acceleration waveform for comparison. This vibration acceleration waveform is a waveform that has been multiplied by an amplifier and processed by a 5 kHz low-pass filter. From the results of this vibration measurement test, it was confirmed that the characteristics of the vibration of the rolling bearing having a scratch on the outer ring can be accurately measured by using the inverse magnetostrictive vibration speed sensor 1 of the present invention.

<Results of cryogenic vibration>
Further, it was confirmed that the inverse magnetostrictive vibration speed sensor 1 of the present invention can appropriately perform vibration measurement without a power source even at −196 ° C. (liquid nitrogen temperature). This is because the inverse magnetostrictive vibration speed sensor 1 of the present invention does not require a complicated spring structure by making the entire shape of the magnetostrictive spring materials 6 and 7 into a trapezoidal structure. By using the effect and making a magnetic bridge, it is possible to cope with changes from extremely low temperatures to high temperatures. It is possible to perform vibration measurement that is highly accurate and suitable for environmental resistance.

FIG. 9 is a schematic front view showing an inverse magnetostrictive vibration speed sensor of the second embodiment.
In the inverse magnetostrictive vibration speed sensor 21 of the second embodiment, the inclination directions of the magnetostrictive spring members 6 and 7 are different from those of the first embodiment. The longitudinal line of the column part 2 and the longitudinal line of the weight part 5 are arranged in parallel, and the two magnetostrictive spring materials 6 and 7 connecting the pillar part 2 and the weight part 5 are not parallel. The state is the same. Even when the magnetostrictive spring members 6 and 7 having such a configuration are arranged so as to have a trapezoidal structure, they are not deformed into a parallelogram by vibration.

  Even in the configuration of the inverse magnetostrictive vibration speed sensor 21 of the second embodiment, when a tensile force is applied to the first magnetostrictive spring material 6 when the support column 2 or the weight portion 5 vibrates up and down, the second magnetostrictive spring material is conversely. A compression force is applied to 7. When a compressive force is applied to the first magnetostrictive spring material 6, a tensile force is applied to the second magnetostrictive spring material 7. As a result, in the magnetostriction detection coil 3, the amount of change in magnetic permeability due to the inverse magnetostriction effect of the magnetostrictive element can be doubled, and the measured output value can be increased.

FIG. 10 is a schematic explanatory diagram illustrating an inverse magnetostrictive vibration speed sensor according to the third embodiment.
The reverse magnetostrictive vibration speed sensor 31 of the third embodiment differs from the arrangement of the first and second embodiments in that the mounting position of the magnet 32 is not in the weight portion 5 but in the support portion 2. In this way, even when the magnet 32 is on the support 2, the magnetostriction detection coil 3 can detect a change in permeability due to the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7. it can.

  In the inverse magnetostrictive vibration speed sensor 31 of the third embodiment, the magnetostriction detection coil 3 is mounted at two locations so as to sandwich the magnet 32 in order to mount the magnet 32 in the middle of the column 2. Even if such a magnetostriction detection coil 3 is arranged, the detection effect does not change.

FIG. 11 is a schematic explanatory diagram illustrating an inverse magnetostrictive vibration speed sensor according to a fourth embodiment.
In the inverse magnetostrictive vibration speed sensor 41 of the fourth embodiment, the inclination directions of the magnetostrictive spring members 6 and 7 are different from those of the third embodiment. When a tensile force is applied to the first magnetostrictive spring material 6 when the column portion 2 or the weight portion 5 vibrates up and down, on the contrary, a compressive force is applied to the second magnetostrictive spring material 7. When a compressive force is applied to the first magnetostrictive spring material 6, a tensile force is applied to the second magnetostrictive spring material 7. As a result, in the magnetostriction detection coil 3, the amount of change in magnetic permeability due to the inverse magnetostriction effect of the magnetostrictive element can be doubled, and the measured output value can be increased.

  The present invention does not require a spring structure having a complicated configuration, and uses the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material 6 and the second magnetostrictive spring material 7 having simple shapes to form a magnetic bridge. Thus, if it is possible to cope with a change from extremely low temperature to high temperature and perform vibration measurement that is highly accurate and stable and adapts to environmental resistance, the present invention is not limited to the embodiment of the present invention described above. Of course, various changes can be made without departing from the scope of the invention.

  The present invention is not limited to the measurement of vibration of a rotating device such as a compressor, but can be used for measurement as long as it vibrates like other devices, devices, and vehicles.

DESCRIPTION OF SYMBOLS 1 Vibration speed sensor 2 Support | pillar part 3 Magnetostriction detection coil 3a 1st magnetostriction detection coil 3b 2nd magnetostriction detection coil 4 Magnet 5 Weight part 6 1st magnetostriction spring material 7 2nd magnetostriction spring material 21 Vibration speed sensor 31 Vibration speed sensor 32 Magnet 41 Vibration speed sensor

Claims (8)

An inverse magnetostrictive vibration velocity sensor (1, 21) that measures the vibration velocity by the inverse magnetostriction effect of the magnetostrictive element,
A magnetostriction detection coil (3) in which the support (2) is inserted;
A weight portion (5) having a magnet (4);
A first magnetostrictive spring material (6) comprising a magnetostrictive element in which one side of the support column (2) and one side of the weight (5) are connected;
A second magnetostrictive spring material (7) composed of a magnetostrictive element connecting the other side of the support column (2) and the other side of the weight (5),
A magnetic bridge is formed as a closed magnetic path by the support (2), the magnet (4), the weight (5), the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7),
The first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are inclined in directions opposite to each other between the column portion (2) and the weight portion (5) arranged in parallel. As a result, the tensile force generated by the vertical vibration of the column portion (2) and the weight portion (5) is applied to the first magnetostrictive spring material (6) or the second magnetostrictive spring material (7), and the compressive force is applied to the second. In addition to the magnetostrictive spring material (7) or the first magnetostrictive spring material (6),
The change in permeability due to the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) is detected by the magnetostrictive detection coil (3), and the vibration velocity is measured by the induced electromotive force. An inverse magnetostrictive vibration speed sensor, characterized in that it is configured to obtain. An inverse magnetostrictive vibration speed sensor (31, 41) for measuring vibration speed by an inverse magnetostriction effect of a magnetostrictive element,
A magnetostriction detection coil (3) in which a support (2) having a magnet (32) is inserted;
A weight (5);
A first magnetostrictive spring material (6) comprising a magnetostrictive element in which one side of the support column (2) and one side of the weight (5) are connected;
A second magnetostrictive spring material (7) composed of a magnetostrictive element connecting the other side of the support column (2) and the other side of the weight (5),
A magnetic bridge is formed as a closed magnetic path by the support (2), the weight (5), the first magnetostrictive spring material (6), the second magnetostrictive spring material (7) and the magnet (32),
The first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are inclined in directions opposite to each other between the column portion (2) and the weight portion (5) arranged in parallel. As a result, the tensile force generated by the vertical vibration of the column portion (2) and the weight portion (5) is applied to the first magnetostrictive spring material (6) or the second magnetostrictive spring material (7), and the compressive force is applied to the second. In addition to the magnetostrictive spring material (7) or the first magnetostrictive spring material (6),
The change in permeability due to the inverse magnetostriction effect of the magnetostrictive elements of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) is detected by the magnetostrictive detection coil (3), and the vibration velocity is measured by the induced electromotive force. An inverse magnetostrictive vibration speed sensor, characterized in that it is configured to be able to perform.   3. The inverse magnetostrictive vibration velocity sensor according to claim 1 or 2, wherein the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are both plate-like members having flexibility.   4. The inverse magnetostrictive vibration speed sensor according to claim 1, wherein the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are both oval ring-shaped members.   5. The inverse magnetostriction according to claim 1, wherein the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) use magnetostrictive elements made of an iron-cobalt alloy. Vibration speed sensor.   The magnetostriction detection coil (3) is divided into a first magnetostriction detection coil (3a) and a second magnetostriction detection coil (3b) wound in the opposite direction to the first magnetostriction detection coil (3a). 6. The inverse magnetostrictive vibration speed sensor according to claim 1, which is a magnetostrictive detection coil. The magnetostriction detection coil (3), the magnets (4, 32), the weight (5), one side of the column (2) and one side of the weight (5) in which the column (2) is inserted. A first magnetostrictive spring material (6) composed of coupled magnetostrictive elements, and a second magnetostrictive spring material (7) composed of a magnetostrictive element coupling the other side of the support column (2) and the other side of the weight (5). ), And the magnetic permeability of the magnetostrictive element of the first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) in the inverse magnetostrictive vibration velocity sensor (1, 21, 31, 41). A method of detecting a change with a magnetostriction detection coil (3) and measuring a vibration speed by an induced electromotive voltage,
A magnetic bridge is formed as a closed magnetic path by the weight portion (5), the magnet (4, 32), the first magnetostrictive spring material (6), the second magnetostrictive spring material (7), and the support post portion (2),
The first magnetostrictive spring material (6) and the second magnetostrictive spring material (7) are inclined in directions opposite to each other between the column portion (2) and the weight portion (5) arranged in parallel. By crossing
When the tensile force generated by the vertical vibration of the column (2) and the weight (5) is applied to the first magnetostrictive spring material (6), a compressive force is applied to the second magnetostrictive spring material (7), and conversely When the compressive force is applied to the first magnetostrictive spring material (6), the tensile force is applied to the second magnetostrictive spring material (7). A measuring method using an inverse magnetostrictive vibration velocity sensor, characterized in that the amount of change is doubled.   The magnetostriction detection coil (3) is divided into a first magnetostriction detection coil (3a) and a second magnetostriction detection coil (3b) in which the first magnetostriction detection coil (3a) is wound in the opposite direction. 8. A measuring method using an inverse magnetostrictive vibration velocity sensor according to claim 7, wherein a magnetostrictive detection coil is used.