JP2003098031A - Excitation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evaluate accurately a vibration characteristic regardless of the shape of a turbine blade 2. SOLUTION: The turbine blade 2 is excited by a magnetic force by supplying an electromagnet 3 with an electric power. Hereby, the mass of the electromagnet 3 does not exert an influence on the mass of the turbine blade 2, and a strong exciting force can be acquired. The vibration characteristic, therefore, can be evaluated accurately regardless of the shape of the turbine blade 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration device for evaluating vibration characteristics by vibrating an object to be measured such as a blade of an axial flow driving means.

[0002]

2. Description of the Related Art Measuring the vibration stress and resonance point of the stationary blades and moving blades of gas turbines, steam turbines, and compressors, which are axial-flow driven devices, and analyzing and evaluating the vibration characteristics is called the durability of the devices. It is important to understand the characteristics of, and it becomes possible to verify the finite element method model. The stationary and moving blades are
Since the vibration is damped by the frictional force due to some deformation during operation, the vibration for evaluating the vibration characteristics requires a large vibration force to some extent. Also, a large excitation force is required to evaluate the limit of stress. For this reason, the conventional vibration device for vibrating the stationary blade or the moving blade has a vibrating means such as a piezoelectric element directly attached to the stationary blade or the moving blade to directly move the stationary blade or the moving blade at a desired frequency with a large force. I was shaking.

[0003]

In recent years, with the demand for higher performance of axial flow drive equipment, the vanes and moving blades are becoming thinner. In the case of a vibrating device in which a vibrating means such as a piezoelectric element is directly attached to a thin vane or a moving blade, the mass of the vibrating means itself may affect the vibration characteristics. Therefore, it is desired to develop a vibrating device in which the mass of the vibrating means does not affect the mass of the object to be measured such as the stationary blade and the moving blade, and moreover, a large vibrating force can be obtained. The current situation.

The present invention has been made in view of the above circumstances, and provides a vibrating device in which the mass of the vibrating means does not affect the mass of the object to be measured and a large vibrating force is obtained. The purpose is to

[0005]

In order to achieve the above object, the structure of the present invention comprises a vibrating means for vibrating the object to be measured in a state where the relative mass with the object to be measured is substantially zero. Is characterized by. The vibrating means is a means for vibrating the object to be measured with an electromagnetic force or a magnetic force.
Further, the vibrating means is means for vibrating the object to be measured with a magnetic force by supplying electric power to the electromagnet.

A load cell is provided at the mounting portion of the electromagnet, and a control means for controlling the electric power supplied to the electromagnet according to the signal of the load cell is provided. Further, it is characterized in that a gap sensor for detecting a gap with respect to the object to be measured is provided, and a control means for controlling electric power supplied to the electromagnet according to a signal from the gap sensor is provided. Further, a strain gauge is attached to the object to be measured, and a control means for controlling the power supplied to the electromagnet according to the signal of the strain gauge is provided. Further, it is characterized in that a plurality of electromagnets are provided.
Further, it is characterized by further comprising air vibrating means for vibrating the object to be measured by air pressure.

The vibrating means is a means for vibrating the object to be measured by an electromagnetic force generated by an electric current flowing through the object to be measured. In addition, a pair of electrodes to which an alternating current is supplied is attached to the object to be measured, and a magnet that generates an exciting force on the object to be measured is generated between the pair of electrodes and the magnetic field induced by the current applied to the object to be measured. It is characterized by having. In addition, a coil is provided to generate an eddy current in the object to be measured by an alternating current, and a magnet is provided to generate an exciting force to the object to be measured with the magnetic field induced by the eddy current generated in the object to be measured by the coil. It is characterized by that. In addition, a non-contact electrode to which an alternating current is supplied to the object to be measured is provided, and a magnet for generating an exciting force on the object to be measured is generated between the non-contact electrode and the magnetic field induced by the current applied to the object to be measured. It is characterized by having.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a vibrating device of the present invention will be described below with reference to the drawings. 1 to 9 show a schematic configuration of a vibrating device according to first to ninth embodiments of the present invention. In each embodiment, the same members are designated by the same reference numerals and duplicate description is omitted.

In the illustrated embodiment, a turbine blade is taken as an example of the object to be measured, but the object to be measured is a blade of another axial flow drive device such as a compressor or a blower, or the like. The present invention can be applied to vibration of an object to be measured for evaluating vibration characteristics.

A first embodiment will be described with reference to FIG.

A base end of a turbine blade 2 as an object to be measured is fixed to the fixing jig 1. The turbine blade 2 is made of a magnetic material. An electromagnet 3 is arranged adjacent to the turbine blade 2, and electric power is supplied to the electromagnet 3 from an oscillator 5 via an amplifier 4 and excited at a predetermined frequency. The turbine blade 2 is vibrated at a desired frequency and a predetermined vibrating force by the electromagnetic force generated by the excitation of the electromagnet 3.

Therefore, the turbine blade 2 can be excited without contact, the mass of the electromagnet 3 does not affect the mass of the turbine blade 2, and the mass of the electromagnet 3 itself affects the vibration characteristics. Turbine blade 2 thinned without
Even in this case, the vibration characteristic can be accurately evaluated.

A second embodiment will be described with reference to FIG.

A load cell 7 is provided on the mounting portion 6 of the electromagnet 3, and a detection signal of the load cell 7 is input to a controller 8 as a control means. The controller 8 outputs a control command for power supply to the oscillator 5 in response to the detection signal of the load cell 7, and supplies the oscillator 5 to the electromagnet 3 so that a constant exciting force can be obtained regardless of the frequency characteristic of the oscillator 5. Power is controlled. Further, the electric power supplied to the oscillator 5 is controlled so as to obtain a desired and desired excitation force.

Therefore, the turbine blade 2 can be excited in a non-contact manner with a constant exciting force or a desired exciting force, and the mass of the electromagnet 3 does not affect the mass of the turbine blade 2. The vibration characteristics can be accurately evaluated even in the thin turbine blade 2 in a state where the mass of the electromagnet 3 itself does not affect the vibration characteristics.

A third embodiment will be described with reference to FIG.

At the tip portion of the turbine blade 2, the turbine blade 2
A gap sensor 9 for detecting a gap is provided, and a detection signal of the gap sensor 9 is input to the controller 8. The controller 8 outputs a control command for the supplied power to the oscillator 5 according to the detection signal of the gap sensor 9 so that a constant gap is formed regardless of the frequency characteristic of the oscillator 5.
That is, the electric power supplied to the oscillator 5 is controlled so as to be in a constant displacement state. Also, so that the required and desired gap is obtained,
That is, the power supplied to the oscillator 5 is controlled so that the desired displacement state is achieved.

Therefore, the turbine blade 2 can be vibrated in a non-contact manner in a constant displacement state or a desired displacement state, the mass of the electromagnet 3 does not affect the mass of the turbine blade 2, and the electromagnet is not affected. Even if the turbine blade 2 is thinned in a state where the mass of 3 itself does not affect the vibration characteristics, the vibration characteristics can be accurately evaluated.

A fourth embodiment will be described with reference to FIG.

At the base end portion of the turbine blade 2, the turbine blade 2
The strain gauge 10 for detecting the strain is attached, and the detection signal of the strain gauge 10 is input to the controller 8. The controller 8 outputs a control command for the power supply to the oscillator 5 according to the detection signal of the strain gauge 10 so that the strain becomes constant regardless of the frequency characteristic of the oscillator 5, that is, the constant stress is applied. The power supply of the oscillator 5 is controlled. Further, the electric power supplied to the oscillator 5 is controlled so as to obtain a necessary and desired strain, that is, to receive a desired stress.

Therefore, the turbine blade 2 can be vibrated in a constant stress state or a desired stress state without contact, the mass of the electromagnet 3 does not affect the mass of the turbine blade 2, and the electromagnet can be excited. Even if the turbine blade 2 is thinned in a state where the mass of 3 itself does not affect the vibration characteristics, the vibration characteristics can be accurately evaluated.

The load cell 7, the gap sensor 9 and the strain gauge 10 described above may be provided in an appropriate combination to appropriately combine the excitation force control, the displacement control and the stress control.

A fifth embodiment will be described with reference to FIG.

Three electromagnets 3 are arranged at appropriate positions adjacent to the turbine blades 2, and the electromagnets 3 are individually supplied with electric power from the oscillator 5 via the amplifiers 4 according to a command from the controller 8 to have a predetermined frequency. Is excited by. By exciting the three electromagnets 3 individually, the turbine blade 2 is excited in an arbitrary excitation mode by an electromagnetic force.

Therefore, the turbine blade 2 can be excited in any vibration mode without contact, the mass of the electromagnet 3 does not affect the mass of the turbine blade 2, and the electromagnet 3
Even if the turbine blade 2 is thinned in a state where its own mass does not affect the vibration characteristics, it is possible to accurately evaluate the vibration characteristics in various vibration modes. Further, even if the exciting force of one electromagnet 3 is reduced, a large exciting force can be obtained. Furthermore, by giving a phase difference to the excitation of each electromagnet 3 according to a command from the controller 8, it is possible to simulate vibration such as fluid force. In addition, the electromagnet 3 is two or three.
It is possible to provide an arbitrary number of one or more.

A sixth embodiment will be described with reference to FIG.

An air siren 11 as an air pressurizing means for vibrating the turbine blade 2 by air pressure in the vicinity of the electromagnet 3.
And a pressure gauge 12 for detecting the air pressure from the air siren 11. The detection signal of the pressure gauge 12 is input to the controller 8. The controller 8 outputs a control command for power supply to the oscillator 5 according to the detection signal of the pressure gauge 12, and the power supply to the oscillator 5 is controlled so that the air pressure from the air siren 11 and the excitation of the electromagnet 3 are synchronized. .

Therefore, the turbine blade 2 can be vibrated in a non-contact manner with a large exciting force, the mass of the electromagnet 3 does not affect the mass of the turbine blade 2, and the mass of the electromagnet 3 itself vibrates. Even if the turbine blade 2 is thinned without affecting the characteristics, the vibration characteristics can be accurately evaluated.

A seventh embodiment will be described with reference to FIG.

A pair of electrodes 13a, whose relative mass with the turbine blade 2 is substantially zero, is provided at the tip end portion and the base end portion of the turbine blade 2,
13b is attached, and electric power is supplied to the pair of electrodes 13a and 13b from the AC power supply 14. Permanent magnets 15 as magnets are provided in the vibration section around the turbine blades 2. An electromagnet can be used as the magnet. The turbine blade 2 is a conductor, and is supplied with AC power from the AC power supply 14 to generate a pair of electrodes 13 a, 13 a.
An alternating current A is passed during b. A magnetic field G is induced between the permanent magnets 15 when the alternating current A is passed, and a force F in a direction orthogonal to the alternating current A and the magnetic field G is generated in the turbine blade 2 according to Fleming's law and becomes an exciting force. .

Therefore, the turbine blade 2 can be self-excited, the mass of the vibrating means does not affect the mass of the turbine blade 2, and the mass of the vibrating means itself affects the vibration characteristics. Even if the turbine blade 2 is thinned in the absence, it is possible to accurately evaluate the vibration characteristics. Further, if the turbine blade 2 is a conductor, it can be vibrated even if it is not a magnetic body, and an arbitrary portion can be vibrated by arranging the pair of electrodes 13a and 13b and the permanent magnet 15.

An eighth embodiment will be described with reference to FIG.

A coil 16 is arranged close to the turbine blade 2, and electric power is supplied to the coil 16 from an AC power supply 14. Further, a permanent magnet 17 is arranged so as to face the coil 16. When AC power is supplied from the AC power supply 14 to the coil 16, an eddy current P is generated in the turbine blade 2, a magnetic field corresponding to the eddy current P is induced, and an exciting force is generated between the magnetic field and the permanent magnet 17. Occurs.

Therefore, the turbine blade 2 can be self-excited, the mass of the vibrating means does not affect the mass of the turbine blade 2, and the mass of the vibrating means itself affects the vibration characteristics. Even if the turbine blade 2 is thinned in the absence, it is possible to accurately evaluate the vibration characteristics. If the turbine blade 2 is a conductor, it can be vibrated even if it is not a magnetic body, and an arbitrary portion can be vibrated by disposing the coil 16 and the permanent magnet 17.

A ninth embodiment will be described with reference to FIG.

The electrode 1 which is not in contact with the tip of the turbine blade 2
8 is arranged, and AC power is supplied to the electrode 18 from an AC power supply 19 of which one side is grounded. A permanent magnet 17 as a magnet is provided facing the electrode 18. An electromagnet can be used as the magnet. The turbine blade 2 is a conductor, and when the AC power supply 14 supplies electric power to the electrode 18, an alternating current A is caused to flow through the turbine blade 2 due to electrostatic capacitance. A magnetic field is induced by the flow of the alternating current A, and an exciting force is generated in the turbine blade 2 by the permanent magnet 17.

Therefore, the turbine blade 2 can be self-excited, the mass of the vibrating means does not affect the mass of the turbine blade 2, and the mass of the vibrating means itself affects the vibration characteristics. Even if the turbine blade 2 is thinned in the absence, it is possible to accurately evaluate the vibration characteristics. Further, if the turbine blade 2 is a conductor, it can be vibrated even if it is not a magnetic body, and an arbitrary portion can be vibrated by disposing the permanent magnet 17. It is also possible to connect the AC power supply 14 by providing the non-contact electrode 18 at the tip and the base end without grounding one of the AC power supplies 14.

In the above-described vibrating device, the mass of the vibrating means does not affect the mass of the turbine blade 2. Therefore, even if the turbine blade 2 is thin, the vibration characteristics can be accurately evaluated. Even if the turbine blade 2 can be damped by friction, it can be vibrated with a large force capable of dampening, and the required vibration characteristics can be accurately evaluated. Therefore, the vibration characteristics of the object to be measured such as the stationary blade and the moving blade can be accurately obtained, and the design margin can be reduced to reduce the design cost.

[0039]

Since the vibrating device of the present invention is provided with the vibrating means for vibrating the object to be measured in a state where the relative mass to the object to be measured is substantially zero, the mass of the vibrating means is to be measured. A large excitation force can be obtained without affecting the mass of the object. As a result, the vibration characteristic can be accurately evaluated regardless of the shape of the object to be measured.

Since the vibrating means is a means for vibrating the object to be measured by electromagnetic force or magnetic force, it vibrates the object to be measured in a non-contact state or in a state where the relative mass with the object to be measured is substantially zero. It is possible to let

Further, since the vibrating means is a means for vibrating the object to be measured by the magnetic force by supplying electric power to the electromagnet, it is possible to vibrate the object to be measured in a non-contact state.

Further, since the load cell is provided at the mounting portion of the electromagnet and the control means for controlling the electric power supplied to the electromagnet according to the signal of the load cell is provided, the object to be measured can be excited with a constant exciting force or a desired exciting force. Can be excited.

Further, since the gap sensor for detecting the gap with respect to the object to be measured is provided and the control means for controlling the electric power supplied to the electromagnet according to the signal of the gap sensor is provided, the constant displacement state or the desired displacement state can be obtained. It becomes possible to excite the object to be measured.

Further, since the strain gauge is attached to the object to be measured and the control means for controlling the electric power supplied to the electromagnet in accordance with the signal of the strain gauge is provided, the object to be measured is kept in a constant stress state or a desired stress state. It becomes possible to excite.

Further, since a plurality of electromagnets are provided, it becomes possible to excite the object to be measured in any excitation mode, and it is possible to reduce the excitation force of one electromagnet. Moreover, it is possible to simulate vibration such as fluid force by providing a phase difference.

Further, since the air vibrating means for vibrating the object to be measured by the air pressure is further provided, it is possible to obtain a large vibrating force with one electromagnet.

Further, since the vibrating means is a means for vibrating the object to be measured by the electromagnetic force generated by the electric current applied to the object to be measured, it is non-contact or the relative mass with the object to be measured becomes substantially zero. It becomes possible to vibrate the object to be measured in this state.

Further, a pair of electrodes to which an alternating current is supplied is attached to the object to be measured, and an exciting force is generated on the object to be measured between the pair of electrodes and a magnetic field induced by the current applied to the object to be measured. Since the magnet is provided, the object to be measured can be vibrated while the relative mass with the object to be measured is substantially zero.

A coil for generating an eddy current in the object to be measured by an alternating current is provided, and an exciting force is generated in the object to be measured with the magnetic field induced by the eddy current generated in the object to be measured by the coil. Since the magnet is provided, the object to be measured can be vibrated in a non-contact manner.

A non-contact electrode for supplying an alternating current to the object to be measured is provided, and a magnet for generating an exciting force on the object to be measured with the magnetic field induced by the current applied to the object to be measured by the non-contact electrode. Since it is provided, it becomes possible to vibrate the object to be measured without contact.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a vibration device according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a vibrating device according to a second embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a vibrating device according to a third embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a vibrating device according to a fourth embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a vibrating device according to a fifth embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a vibrating device according to a sixth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a vibrating device according to a seventh embodiment of the present invention.

FIG. 8 is a schematic configuration diagram of a vibrating device according to an eighth embodiment of the present invention.

FIG. 9 is a schematic configuration diagram of a vibrating device according to a ninth embodiment of the present invention.

[Explanation of symbols]

1 Fixing jig 2 turbine blades 3 electromagnet 4 amplifier 5 oscillators 6 Mounting part 7 load cell 8 controller 9 Gap sensor 10 strain gauge 11 air siren 12 pressure gauge 13a, 13b electrodes 14 AC power supply 15 Permanent magnet 16 coils 17 permanent magnet 18 electrodes 19 AC power supply

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Katsuya Yamashita             2-1-1 Niihama, Arai-cho, Takasago City, Hyogo Prefecture             Takasago Laboratory, Mitsubishi Heavy Industries, Ltd. (72) Inventor Shinya Iizuka             2-1-1 Niihama, Arai-cho, Takasago City, Hyogo Prefecture             Takasago Laboratory, Mitsubishi Heavy Industries, Ltd.

Claims (12)

[Claims] 1. A vibrating device comprising a vibrating means for vibrating an object to be measured in a state where a relative mass with the object to be measured is substantially zero. 2. The vibrating device according to claim 1, wherein the vibrating means is a means for vibrating the object to be measured by electromagnetic force or magnetic force. 3. The vibrating device according to claim 2, wherein the vibrating means is means for vibrating the object to be measured with a magnetic force by supplying electric power to an electromagnet. 4. The vibrating device according to claim 3, wherein a load cell is provided in the mounting portion of the electromagnet, and control means is provided for controlling the electric power supplied to the electromagnet according to a signal of the load cell. 5. The vibration generator according to claim 3, further comprising a gap sensor for detecting a gap with respect to the object to be measured, and a control means for controlling electric power supplied to the electromagnet according to a signal from the gap sensor. apparatus. 6. The vibrating device according to claim 3, wherein a strain gauge is attached to the object to be measured, and control means for controlling the electric power supplied to the electromagnet according to the signal of the strain gauge is provided. 7. The vibrating device according to claim 3, comprising a plurality of electromagnets. 8. The vibrating device according to claim 3, further comprising air vibrating means for vibrating the object to be measured by air pressure. 9. The vibrating device according to claim 2, wherein the vibrating means is a means for vibrating the object to be measured by an electromagnetic force generated by an electric current flowing through the object to be measured. 10. The object to be measured according to claim 9, wherein a pair of electrodes to which an alternating current is supplied is attached to the object to be measured, and a magnetic field induced by a current applied to the object to be measured by the pair of electrodes is applied to the object to be measured. A vibrating device comprising a magnet for generating a vibrating force. 11. A coil for generating an eddy current in an object to be measured by an alternating current according to claim 9, wherein the coil is applied to the object to be measured with a magnetic field induced by the eddy current generated in the object to be measured by the coil. A vibrating device comprising a magnet for generating a vibrating force. 12. The non-contact electrode to which an alternating current is supplied to the object to be measured according to claim 9, and the object to be measured between the object and the magnetic field induced by the current applied to the object to be measured by the non-contact electrode. A vibrating device comprising a magnet for generating a vibrating force.