JPH06307919A - Run out measuring equipment for rotary part - Google Patents

Abstract

PURPOSE:To provide an equipment for measuring the vibration or the run out of rotary shaft directly. CONSTITUTION:The run out measuring equipment for rotary part comprises an exciting coil 9b and a detection coil 9a, wherein the detection coil 9a comprises a pair of coils spaced apart from each other and connected such that the currents flow in the opposite directions. The pair of coils are disposed oppositely through the axes of rotary shafts 9e, 4 to be measured. A plurality of the detection coils 9a are secured oppositely at predetermined positions in stationary part while surrounding the rotary shafts 9e, 4 and a plurality of exciting coils 9b are disposed oppositely to the detection coils 9a around the rotary shafts 9e, 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring device used for monitoring abnormalities such as vibration and shaft runout of a rotating shaft in rotating equipment such as a generator. The present invention relates to a rotating part shake measuring device which can be directly measured.

[0002]

2. Description of the Related Art In rotating machines such as generators and electric motors,
The rotating part is supported by the bearing part of the stationary part and is driven to rotate, but vibration and shaft run-out are increased depending on the usage conditions and environmental conditions, damage due to contact between the rotating part and the stationary part, burning of the bearing part, etc. There are cases in which a rotating machine may lead to a serious accident.

Therefore, as for a rotating machine, which is required to be assembled with a rotating part and a stationary part with high accuracy, an alarm device is conventionally provided in order to prevent the contact, and there is a risk of contact such as vibration and shaft run-out in advance. It uses a method of detecting and stopping.

However, as the alarm device, usually, a method of detecting a contact risk such as vibration or shaft runout by a secondary method such as an increase in bearing temperature is usually used. It cannot be said that the early detection is performed to stop the operation of the rotating machine. Therefore, in recent years, the method of detecting the vibration itself has been gradually adopted, but even with this method, the vibration of the rotating shaft is not directly measured but the vibration of the bearing base is measured. It is an indirect method.

The method of monitoring the vibration of the rotating shaft by measuring the vibration of the bearing base is highly reliable because the magnitude of the transmitted vibration is closely related to the vibration of the rotating shaft. , It cannot be detected while the vibration of the rotating shaft is small.

[0006]

In a rotating machine such as a generator or an electric motor, the rotating part is supported by a bearing part of a stationary part and is driven to rotate. However, vibration and shaft run-out are caused by its use condition and environmental condition. However, there are cases in which the rotating part and stationary part may come into contact with each other, and the bearing part may be burned out, leading to a serious accident as a rotating machine. By installing an alarm device to detect the danger of contact such as vibration and shaft shake in advance,
I'm trying to stop it.

However, this alarm device detects the vibration of the rotating shaft by an indirect detection method of measuring the bearing temperature and the vibration of the bearing base and issues an alarm, and directly detects the vibration of the rotating shaft. Does not give an alarm. Therefore, the criteria for issuing an alarm tend to be ambiguous, and it is difficult to issue an alarm accurately.

That is, the detection of danger by the alarm device is
When a situation in which there is a danger of shaft damage, such as an increase in shaft vibration, is taken to take measures such as stopping the operation to prevent it, the rotating shaft is slightly vibrating. If an alarm is issued in such a state, stable operation cannot be performed, and conversely, if an alarm is issued after a certain amount of vibration occurs, it is already too late and the danger cannot be avoided.

Therefore, in order to issue an alarm at an appropriate stage, it is necessary to develop a device capable of directly measuring the magnitude of the shake of the rotary shaft. Therefore, an object of the present invention is to provide a rotating portion shake measuring apparatus capable of directly measuring the vibration and shaft shake of a rotating shaft.

[0010]

In order to achieve the above object, the present invention is configured as follows. That is, an exciting coil (superconducting coil) and a detecting coil (guide coil) are used, and the detecting coil is constructed by connecting a pair of coils arranged apart from each other so that currents flow in directions opposite to each other. The detection coil is arranged such that the pair of coils are opposed to each other via the axis of the rotation shaft to be measured, and the detection coil is fixed in a stationary portion so as to be opposed to and spaced from the rotation shaft. A plurality of exciting coils are fixed at positions, and a plurality of the exciting coils are provided around the rotating shaft so as to face the detecting coils.

[0011]

The present invention applies the principle of null flux. The principle is that a superconducting coil and a guide coil are used. When the superconducting coil is configured to be connected so as to flow, and the superconducting coil passes between a pair of coils that form a guide coil, if the coils are in a fixed position, the paired coils will have the same magnitude but opposite currents. Since they are induced, they cancel each other out and have no electromagnetic effect. However, when the superconducting coil passes between the pair of coils forming the guide coil in an unbalanced manner, the coil closer to the distance is selected. A large induced current is generated and an electromagnetic repulsive force is generated.At a distant place, this induced current flows in the opposite direction, so an attractive force is generated and the positional relationship between the guide coil and the superconducting coil is returned to the normal position. It is said that the action to do works It is intended.

The present invention utilizes the principle of null flux as the above-mentioned configuration, and the detection coil (guide coil) is formed by connecting a pair of coils arranged apart from each other so that currents flow in opposite directions. The detection coil is arranged such that the pair of coils face each other via the axis of the rotation shaft, and the fixed position of the stationary portion is set so that the detection coil surrounds the rotation shaft and is spaced apart from each other. Since a plurality of exciting coils (superconducting coils) are provided around the rotating shaft so as to face the above-mentioned detecting coil, when the detecting coil approaches the exciting coil, an induced current is generated in the detecting coil. The induced current corresponds to the distance from the exciting coil.

Therefore, when the rotary shaft is eccentric from the fixed position, of the coils forming the detection coil, the induced current is large on the side closer to the exciting coil and the exciting coil on the other side. Since the induced current becomes small and the current of the difference flows into the detection coil, it becomes possible to obtain the detection signal corresponding to the vibration and shake of the rotating shaft, and to directly detect the vibration and shake of the rotating shaft. You will be able to measure.

Further, the above-mentioned operation utilizes the null-flack principle, and since the detection signal corresponding to the amount of shake of the rotary shaft is obtained, the vibration and shake of the rotary shaft can be directly detected with high accuracy. Therefore, the abnormality of the rotating portion can be monitored with high accuracy.

Further, according to the present invention, since the restoring force corresponding to the shake amount of the rotating shaft is applied by the principle of null flux, the rotating shaft is regulated so as not to be displaced from the fixed position. In rotating machines, etc., it has become possible to suppress the rotation axis from moving out of its normal position due to vibration and shake,
Stable operation becomes possible.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an embodiment when the present invention is applied to a generator. In FIG.
Reference numeral 1 is a generator, 2 is a stator, 3 is a rotor, and 4 is a rotating shaft of the generator 1. The rotating shaft 4 is rotatably supported by bearings 5a and 5b provided in the generator 1 near both sides of the shaft. Reference numeral 6 is a water wheel, and 7 is a rotating shaft of the water wheel 6.

The rotating shaft 7 of the water turbine 6 is connected to the rotating shaft 4 of the generator 1. The rotation of the rotating shaft 7 of the water turbine 6 rotationally drives the rotating shaft 4 of the generator 1 to drive the generator 1. Is done. Reference numeral 8 is a bearing that supports the rotating shaft 7 of the water turbine 6.

In the rotating machine according to the present invention, the generator 1 is provided with a rotating shaft shake measuring device 9 for measuring the vibration and shaft shake of the rotating shaft. The rotary shaft deflection measuring device 9 is as shown in FIGS. 2 and 3, and is arranged on the upper side of the rotary shaft (main shaft) 4 of the generator 1.

The rotary shaft shake measuring device 9 includes a detection coil 9a.
And an exciting coil 9b, and a rotating shaft 9e and a collector ring 9c. The exciting coil 9 is provided at the upper end on the rotating shaft 9e side.
b is fixed and arranged, and the lower end of the rotating shaft 9e is firmly attached to the upper part of the rotating shaft (spindle) 4 of the generator 1 with the axis aligned and is rotated integrally with the rotating shaft (spindle) 4. It is composed. The housing 9d is mounted on the housing of the generator 1 and covers the upper part of the rotating shaft 9e.

In the housing 9d, a detection coil 9a is arranged and held at a position facing the exciting coil 9b so as to surround the exciting coil 9b. That is, the rotating part shake measuring device 9 has a structure as shown in FIG. 3, (a) of FIG. 3 is a front view, and (b) is a sectional view taken along line BB of (b) of FIG. Also,
3B is a sectional view taken along line AA of FIG. As shown in the drawing, the rotating-part shake measuring apparatus 9 has a plurality of exciting coils 9b fixedly arranged at a predetermined pitch on the outer circumference of the upper end of a rotating shaft 9e, separated from these exciting coils 9b, and A plurality of detection coils 9 are provided so as to surround the excitation coil 9b.
a is arranged at a predetermined pitch and is fixedly attached to the housing 9d side. The exciting coil 9b and the detecting coil 9a are located at positions facing each other.

The rotating shaft shake measuring apparatus 9 of the present invention applies the principle of null flux, and the content of the principle is as follows. Null flux is a technique for correcting the eccentricity of the travel route of a vehicle, which is used in a linear motor car that is magnetically levitated and travels in a non-contact manner. As shown in FIG. It is composed of an orbital guide coil C2 on the ground.

The induction coil C1 on the vehicle has a loop-shaped closed coil (superconducting coil) arranged vertically on the vehicle with its axial center crossing the direction of travel of the vehicle. Is. A large number of track-side guide coils C2 on the ground are arranged along the track at predetermined intervals, but loop-shaped coils C2a and C2b are arranged so as to form a pair on the left and right with respect to the traveling direction of the vehicle. The left and right loop coils C2a and C2b forming a pair are connected to each other at their end portions so that opposite currents flow in the respective loops.

The track guide coil C2 on the ground is arranged upright so that its loop faces the induction coil C1 on the vehicle. The center of the pair of left and right track guide coils C2 is connected to the guide coil C1 on the vehicle. It is configured to pass. If the right side loop coil C2a is the mountain side and the left side loop coil C2b is the sea side among the track side guide coils C2 formed by the pair of left and right loop coils C2a and C2b, the traveling vehicle is the track side guide coil C2. When running in the center, no current is induced in the guide coil C2 on the track side, and neither force nor loss occurs.

However, when the vehicle deviates from the center, an electric current is induced in proportion to the deviation amount, and a restoring force proportional to the deviation amount is generated. That is, when the traveling vehicle is biased to the sea side from the center, a current that causes a repulsive force flows through the loop coil C2b on the sea side, and this current flows in the opposite direction on the mountain side, so that an attractive force is generated on the mountain side. Therefore, if a vehicle running on the original travel route deviates from the center to either the mountain side or the sea side, a restoring force is generated in proportion to the amount of deviation, and the vehicle travels in the original direction. It is said to be corrected by electromagnetic force so that it comes to the position.

FIG. 5 shows the basic configuration of the rotating shaft shake measuring apparatus 9 according to the present invention. The rotating shaft shake measuring device 9 uses the null flux method, and the exciting coil 9b is attached to the rotating shaft 9e side, and the detection coil (stationary side coil) 9a is provided on the housing 9d side. . The exciting coil 9b has a loop shape and is excited by application of direct current from a direct current power source. The axis of the exciting coil 9b is the rotating shaft 9
It is arranged so as to be orthogonal to e.

The detection coil (stationary side coil) 9a is composed of loop coils a-1 and 9a-2, and a large number of these coils are arranged at predetermined intervals so as to face each other along the peripheral surface of the rotating shaft 9e. The loop coils 9a-1 and 9a-2 are arranged so as to face each other through the axis of the rotating shaft 9e, and both loop coils 9a-1 and 9a-2 forming this pair are end-to-end with each other. The parts are connected to each other so that opposite currents flow in the respective loops.

A plurality of pairs forming such a pair are provided at a predetermined pitch. Each detection coil (stationary coil) 9a
Takes out the currents induced by the loop-shaped coils 9a-1 and 9a-2, respectively, as shaft deflection measurement signals. Then, as shown in FIGS. 2 and 6, the output of each detection coil 9a is separately amplified through an amplifier AMP and then used as a shift signal for each detection coil position. Further, the exciting coil 9b is excited by applying a direct current from the DC power supply DCPWS, but since the exciting coil 9b is provided on the rotating shaft 9e side, the rotating shaft 9e is provided with a collector ring 9c. Collector ring 9
With c, an exciting current is supplied to each exciting coil 9b from an external DC power source DCPWS so as to function as a superconducting coil.

The operation of the present apparatus having such a configuration will be described. In the present apparatus, when a shaft runout or the like occurs during rotation of the rotating machine and the rotary shaft 4 runs out, the rotary shaft runout measuring device 9 obtains a signal corresponding to the runout amount. It will be possible to measure directly regardless of.

That is, the rotating shaft (main shaft) 4 of the generator 1 is fixedly attached to the rotating shaft 9e with the axes aligned, and the exciting coil 9b and the exciting coil 9b are attached to the rotating shaft 9e. The detection coil (stationary coil) 9a is arranged so as to surround the coil. Since the exciting coil 9b and the detection coil (stationary coil) 9a are arranged at the same angular pitch, each detection coil (stationary coil) The loop coils 9a-1 and 9a-2 of 9a always include one of the detection coils (stationary coil) 9a as the rotary shaft rotates.
As a result, electromagnetic waves are generated while moving with the same facing angle.

If current is applied to the exciting coil 9b in the same direction, when the rotating shaft (main shaft) 4 is rotating at a certain position with respect to the bearings 5a and 5b, the shaft is Each detection coil (stationary coil) 9 because there is no shake
The same reverse currents are induced in the loop coils 9a-1 and 9a-2 of a, respectively.
In this state, -1, 9a-2 cancel each other's current, and no current flows.

On the other hand, the rotary shaft (spindle) 4 has bearings 5a and 5b.
When it swings from a predetermined position, the rotary shaft 9e also swings integrally, so that each detection coil (stationary coil) 9a
Loop coils 9a-1 and 9a-2 are opposite exciting coils 9
The distance from each of the detection coils 9 is different.
The current induced in the loop coils 9a-1 and 9a-2 of a depends on the distance from the exciting coil 9b, and a difference current proportional to the amount of deflection of the shaft causes a difference current in each detection coil (stationary coil) 9
a will be induced respectively. Therefore, it becomes possible to measure the direction and magnitude of the shaft runout by the output of each of the detection coils 9a.

Further, the difference between the induced currents generated in the loop coils 9a-1 and 9a-2 of the respective detection coils 9a due to the shaft deflection will flow in the loop coils 9a-1 and 9a-2, respectively. Since the directions of 1 and 9a-2 are opposite, they act as a repulsive force on the side approaching the exciting coil 9b, but act as an attractive force on the side away from the exciting coil 9b, so It acts as a force to restore it to a fixed position by the principle of null flux, and acts to suppress the shake of the rotating shaft (spindle) 4. Therefore, it also has a function of reducing vibration and shake.

The following effects can be obtained from the above contents. (1) It becomes possible to directly measure the shake amount of the rotating shaft in the direction and the size.

(2) Due to the principle of null flux, a restoring force acts according to the amount of deflection of the rotating shaft, and the rotating shaft is regulated so as to rotate in a fixed positional relationship with the bearing. , Suppress abnormal vibration and shaft runout of the rotating shaft,
Stable operation becomes possible.

(3) If the shake amount increases, the force for suppressing it increases in proportion to it, so that there is no contact accident between the rotating shaft and the stationary portion. Further, since the shaft is corrected so that the shaft comes to a normal position, the bearing load can be reduced and the mechanical loss is reduced, so that the mechanical efficiency can be improved.

(4) Since the load on the bearing is reduced,
The maintenance cycle of the bearing can be lengthened, and the maintenance cost can be reduced. In addition, in the above-described embodiment, the rotating part shake measuring device 9 may be provided near the bearing position of the generator 1.

As described above, the present apparatus uses the exciting coil and the detecting coil, and the detecting coil is constructed by connecting a pair of coils arranged apart from each other so that currents flow in directions opposite to each other. The detection coils are arranged such that the pair of coils face each other via the axis of the rotary shaft to be measured, and a fixed position of the stationary portion is arranged so that the detection coils surround the rotary shaft and face each other. And a plurality of the exciting coils are provided around the rotary shaft so as to face the detecting coil, and when the detecting coil approaches the exciting coil, an induced current is generated in the detecting coil, and the exciting coil is excited. When the detection coil approaches different distances from the coil, the magnitude of the induced current generated in the above-mentioned pair of coils forming the detection coil is different, so that a difference current corresponding to the difference in distance is generated. It is obtained so as to obtain a detection signal corresponding to the vibration or shake utilized.

Therefore, in a rotating machine or the like, it is possible to directly measure the vibration and shake of the shaft. Also, since this uses the principle of null flux, a restoring force corresponding to the amount of shake of the rotating shaft is applied,
As a result, the rotating shaft is also regulated so that it does not move out of the fixed position, so it is possible to prevent the rotating shaft from coming out of the fixed position due to shaft vibration or shake, and stable operation is ensured. In addition to the above, it is possible to obtain an advantage that a contact accident between the rotating portion and the stationary portion due to shaft runout or the like is suppressed and damage to the bearing can be prevented. The present invention is not limited to the embodiments described above and shown in the drawings, and can be appropriately modified and implemented within the scope of the invention.

[0039]

As described above in detail, according to the present invention, it becomes possible to directly measure the vibration and shaft runout of the rotating shaft by the principle of null flux, and at the same time, by the principle of null flux. Thus, it becomes possible to suppress the vibration and the shaft runout of the rotary shaft, and it is possible to provide a rotary part runout measuring device capable of preventing damage to the machine and performing stable operation for a long time.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the present invention, which is an overall configuration diagram showing an embodiment in which a rotating part shake measuring device of the present invention is applied to a turbine generator.

FIG. 2 is a front view showing the configuration of a rotating portion shake measuring device according to the present invention, which is an enlarged view of portion A in FIG.

3A and 3B are diagrams showing a configuration example of a rotating portion shake measuring apparatus according to the present invention, in which FIG. 3A is a partially cutaway front view and FIG.

FIG. 4 is a diagram for explaining the principle of the null flux method used in the present invention.

5A and 5B are views for explaining the principle configuration of a rotating part shake measuring device 9 of the present invention.

FIG. 6 is a circuit diagram showing a configuration of a rotating portion shake measuring device 9 of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Generator 4 ... Rotating shaft (spindle) 6 ... Water turbine 7 ... Rotating shaft of water turbine 5a, 5b, 8 ... Bearing 9 ... Rotating part runout measuring device 9a ... Detection coil (stationary side) 9a-1, 9a-2 ... Loop coil constituting the detection coil 9a ... Excitation coil (rotating side) 9c ... Collector ring 9d ... Housing 9e ... Rotating shaft AMP ... Amplifier DCPWS ... DC power supply C1 ... Induction coil C2 on ground ... C2a, C2b ... A loop coil that constitutes the ground side orbit guide coil C2

Claims (1)

[Claims] 1. An exciting coil and a detection coil are used, and the detection coil is formed by connecting a pair of coils arranged apart from each other so that currents flow in directions opposite to each other. The coils are arranged so as to be opposed to each other via the axis of the rotary shaft to be measured, and a plurality of the detection coils are fixed at fixed positions in a stationary portion so as to face each other and surround the rotary shaft, and A rotating part shake measuring apparatus, wherein a plurality of exciting coils are provided around the rotating shaft so as to face the detecting coil.