JP2931563B2 - DC motor diagnostic method and diagnostic jig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diagnostic method and a diagnostic jig for diagnosing whether a so-called flashover occurs in a DC motor.

[0002]

2. Description of the Related Art DC motors use a commutator and a brush to adjust the direction of current flowing through a coil and rotate the coil by a couple acting on the coil, thereby rotating the rotating shaft and increasing the driving force. What you get.

[0003] As such a DC motor, conventionally,
For example, the structure shown in FIG. 9 is known. The DC motor 50 includes a rotating shaft 51, a fixed clamper 52,
It has a mica 53, a commutator 54, a movable clamper 55, a ring spring 56, and a spring retainer 57.

The fixed clamper 52 is supported by a rotating shaft 51 and rotates together with the rotating shaft 51. Fixed clamper 52
A screw hole 52a provided with a screw groove is provided substantially at the center of the upper part of the screw hole 52a. The movable clamper 55 is provided so as to be movable in the axial direction of the rotating shaft 51, and together with the fixed clamper 52,
The commutator 54 can be pressed and pinched via the V mica 53 (insulating material). The movable clamper 55 has a stepped portion 55a for fitting the ring spring 56 on the side opposite to the side that presses and clamps the commutator 54.

The end face of the commutator 54 facing the fixed clamper 52 and the movable clamper 55 is formed in a zigzag shape. Further, the shape of the V mica 53 and the shape of the surface of the fixed clamper 52 and the movable clamper 55 that holds the commutator 54 are also formed in the same zigzag shape.

The ring spring 56 made of spring steel has a step groove 56a on its inner peripheral side for fitting a spring retainer 57. A gap s is provided between the lower surface of the step groove 56 a of the ring spring 56 and the fixed clamper 52. The spring retainer 57 presses the ring spring 56 against the movable clamper 55 by pressing a step groove 56 a of the ring spring 56 (that is, the inner peripheral side of the ring spring 56). The spring retainer 57 is screwed into the screw hole 52a of the fixed clamper 52, and the movable clamper 55
And the clamping force of the commutator 54 by the fixed clamper 52.

When the spring retainer 57 is screwed into the screw hole 52a to press the inner peripheral side of the ring spring 56, the gap s on the lower surface side of the step groove 56a of the ring spring 56 is narrowed.
Therefore, the surface of the ring spring 56 on the side opposite to the side in contact with the movable clamper 55 is inclined with respect to the rotation shaft 51. Hereinafter, this surface is referred to as an inclined surface 56b.

The DC motor 50 is used, for example, in a railway car of a Shinkansen, and is used by rotating a rotating shaft 51 at a high speed. For this reason, a strong outward centrifugal force acts on the commutator 54. However, the commutator 54 is pressed and pinched by the fixed clamper 52 and the movable clamper 55 via the V mica 53 so that the commutator 54 can withstand the centrifugal force. It is doing.

[0009]

When the DC motor 50 is used to some extent for a Shinkansen railway vehicle (particularly a Hikari train called the 100 series), a spark is generated between the commutator 54 and a brush (not shown). In some cases, a phenomenon (called flashover) occurs in which the DC motor 50 is burned and is connected in the circumferential direction to burn the DC motor 50.

In investigating the cause, at first, the grinding accuracy of the commutator 54 or the contamination of the periphery of the commutator 54 with foreign matters were investigated, and measures were taken to improve these points. However, the occurrence of flashover was not suppressed. Therefore, it has been desired to investigate the cause of such a flashover and to develop a diagnostic method capable of preventing the occurrence thereof before it occurs.

Also, when the DC motor 50 is regularly inspected, the DC motor 50 is usually mounted on the line and the inspection is carried out as a continuous operation. Therefore, the flashover diagnosis can be performed easily and quickly on the line. Was required to do so. The present invention has been made in view of the above problems, and has as its object to provide a diagnostic method and a diagnostic jig capable of preventing occurrence of flashover in a DC motor. Another object of the present invention is to provide a diagnostic method and a diagnostic jig capable of performing the flashover diagnosis easily and quickly.

[0012]

Means for Solving the Problems and Effects of the Invention In order to solve the above-mentioned problems, the present inventors have investigated a DC motor in which flashover has occurred. I found that it was the cause. In other words, since the ring spring made of spring steel is loosened, the clamping force of the commutator by the movable clamper and the fixed clamper is loosened, so that the commutator expands to withstand the centrifugal force when the rotating shaft rotates at high speed. It was thought that it deformed, resulting in a spark between the commutator and the brush and flashover.

A first aspect of the present invention relates to a method of diagnosing a DC motor, and more specifically, a fixed clamper fixed to a rotating shaft and rotating with the rotating shaft, and moving in the axial direction of the rotating shaft. A movable clamper that is provided so as to be able to press and pinch a commutator via an insulating material together with the fixed clamper, and presses and presses the commutator among the movable clampers.
A method of diagnosing a DC motor including a spring spring made of a spring steel in contact with a side opposite to a side to be clamped, and a spring retainer pressing an inner peripheral side of the ring spring toward the movable clamper, (1) With regard to the inclination angle formed by the surface of the ring spring opposite to the side in contact with the movable clamper with respect to the rotation axis, the spring retainer presses the inner peripheral side of the ring spring with a predetermined pressing force. (2) measuring the inclination angle after actually using the DC motor,
(3) By comparing the set angle with the measured inclination angle, it is determined whether or not flashover occurs.

In this diagnostic method, first, a set angle is determined. That is, the spring retainer presses the inner peripheral side of the ring spring with a predetermined pressing force. Then, the inner peripheral side of the spring steel ring spring approaches the movable clamper more than the outer peripheral side. Here, the predetermined pressing force is a pressing force when the commutator is not deformed so as to expand outward due to centrifugal force when the DC motor is actually driven in a state where the inner peripheral side of the ring spring is pressed by the spring retainer. Refers to pressure. At this time, the surface of the ring spring on the side opposite to the side in contact with the movable clamper is inclined with respect to the rotation axis, and this inclination angle is determined as a set angle.

Next, after actually using the DC motor,
For example, at the time of periodic inspection, the inclination angle is measured.
As the DC motor is actually used, the ring spring may loosen, for example, because the insulating material shrinks over time and a gap is created between the commutator and each clamper, causing the ring spring to loosen. There is. In particular,
In the case where the insulating material is mica, if mica that is insufficiently dried is used, the mica dries and shrinks with the passage of time, and the above-described gap may be generated, and the ring spring may be loosened.

Then, by comparing the set angle with the inclination angle (measured value), it is determined whether or not flashover occurs. Specifically, if the inclination angle (measured value) is an appropriate value with respect to the set angle, it is determined that there is no risk of flashover, and if the value is inappropriate, it is determined that there is a risk of flashover. I do. Note that the appropriate value at this time is preferably determined empirically through appropriate experiments.

According to the above-described diagnostic method, since the occurrence of flashover can be prevented beforehand, the effect of extending the life of the DC motor can be obtained. In the above-described diagnostic method, a reference surface is provided opposite to a surface of the ring spring opposite to a side in contact with the movable clamper, and a predetermined inner circumferential position and a predetermined outer circumferential position on the same radial direction of the ring spring are determined. Determining a first distance from the inner peripheral position to a reference plane and a second distance from the outer peripheral position to a reference plane, and treating a difference between the first distance and the second distance as the inclination angle. Is preferred. In this case, since the interval between the predetermined inner peripheral position and the predetermined outer peripheral position is constant, the inclination angle is proportional to the difference between the first distance and the second distance. For this reason, the difference between the first distance and the second distance can be treated as the inclination angle. Obtaining such a difference in distance is preferable because it is generally simpler than obtaining an inclination angle.

In the diagnostic method, when measuring the first distance and the second distance, it is preferable to use an eddy current displacement sensor installed on the reference plane. For example, use a micrometer to make contact with the measurement surface of the ring spring (the surface opposite to the side in contact with the movable clamper, also referred to as an inclined surface) for measurement, or use a laser to make contact with the measurement surface. It is also conceivable to measure without, but usually the varnish is applied to the measurement surface of the ring spring, and when using a micrometer, as well as when using a laser, including the thickness of this varnish Measure. In this case, variation in the thickness of the varnish appears as an error, and sufficient accuracy may not be obtained. Therefore, a complicated operation of removing the varnish before the measurement is required, and an operation of applying the varnish again and drying after the measurement is also required. Since drying takes one or two days, it is almost impossible for such a method to be performed on a line as a line work.

On the other hand, when the eddy current displacement sensor is used, the distance to the ring spring can be accurately measured even when the varnish is applied. This is because the eddy current is generated only in the metal. Therefore, operations such as varnish removal, re-application, and drying become unnecessary, and the effect that flashover diagnosis can be performed easily and quickly can be performed on-line as a continuous operation.

Preferably, the eddy current displacement sensor is provided at a position facing each of the inner peripheral position and the outer peripheral position. For example, it is conceivable to make the eddy current displacement sensor movable on the reference plane and move the eddy current displacement sensor between the inner peripheral position and the outer peripheral position to measure the distance. An error may occur due to a shift of the reference plane, and the moving operation is complicated. On the other hand, it is preferable to provide the eddy current displacement sensor at a position opposed to each of the inner peripheral position and the outer peripheral position, since such a problem is solved.

In the case where the distance is measured by the eddy current displacement sensor as described above, it is preferable that the reference plane is provided so that an angle formed with the rotation axis substantially coincides with the set angle. Since the measurable range of the eddy current displacement sensor is relatively narrow (for example, 0 to several mm), if the difference between the first distance and the second distance is large, one of them may not be able to be measured. . Therefore, the angle between the reference plane and the rotation axis is made to substantially match the set angle, the difference between the first distance and the second distance is made small, and one of them is not measured. .

The second aspect of the present invention relates to a jig for diagnosing a DC motor, and more specifically, is fixed to a rotating shaft.
A fixed clamper that rotates with the rotating shaft, a movable clamper that is provided so as to be movable in the axial direction of the rotating shaft, and that can press and pinch a commutator via an insulating material together with the fixed clamper; A jig for diagnosing a DC motor having a ring spring that abuts on the side opposite to the side that presses and clamps the commutator, and a spring retainer that presses the inner peripheral side of the ring spring toward the movable clamper. A reference surface opposed to a surface of the ring spring opposite to the side in contact with the movable clamper; and a predetermined inner circumferential position on the reference surface, the predetermined inner circumferential position of the ring spring in the same radial direction. And an eddy current displacement sensor for measuring a distance from the reference plane for each of the outer peripheral positions.

In this diagnostic jig, the difference between the first distance from the reference plane to a predetermined inner peripheral position and the second distance from the reference plane to a predetermined outer peripheral position is treated as an inclination angle. According to such a jig for diagnosis, since it can be used to carry out the above-described diagnosis method, it is possible to prevent the occurrence of flashover of the DC motor beforehand, and it is possible to prolong the life of the DC motor. can get.

Further, since the eddy current displacement sensor is provided, operations such as varnish removal, re-application, and drying are not required, so that flashover diagnosis can be performed easily and quickly, and is performed on-line as a flow operation. The effect that it can be obtained is obtained. In such a diagnostic jig, it is preferable that the eddy current displacement sensor is provided at a position facing each of the inner peripheral position and the outer peripheral position. The reason for this has already been described in the first section of the present invention. Further, when the distance is measured by the eddy current displacement sensor as described above, it is preferable that the reference plane is provided so that an angle formed with the rotation axis substantially matches the set angle. The reason for this has already been described in the first section of the present invention.

Further, in this diagnostic jig, there is provided a cylindrical body which is slidably supported around the rotary shaft while being inserted into the rotary shaft by a predetermined length, and wherein the reference surface is provided on the cylindrical body. It is preferable that they are provided integrally. In this case, when the cylindrical body is slid around the rotation axis, the reference plane constantly rotates in the same posture with respect to the rotation axis, so that measurement points including the inner and outer peripheral positions can be easily changed. The distance can be measured constantly and accurately. In addition, since the diagnosis can be performed based on data at a plurality of measurement points, the accuracy of the diagnosis is improved.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] The first embodiment relates to a method of diagnosing the occurrence of flashover of a DC motor using a micrometer and a jig for the diagnosis. FIG. 1 is an explanatory diagram of a diagnosis method according to the present embodiment.

First, the set angle θstd of the inclined surface 56b of the ring spring 56 was determined for the DC motor 50 shown in FIG. That is, as shown in FIG. 1, the spring groove 57 a provided on the inner peripheral side of the ring spring 56 was pressed by screwing the spring retainer 57 into the screw hole 52 a of the fixed clamper 52. Then, the gap s on the lower surface side of the step groove 56a of the ring spring 56 is reduced, and the inclination angle θ (see FIG. 1) of the inclined surface 56b of the ring spring 56 with respect to the rotating shaft 51 is increased. This inclination angle θ is
Changed according to the amount of screwing. And the spring retainer 57
While properly changing the screwing amount of the DC motor 5
When the commutator 54 is not deformed so as to expand outward due to the centrifugal force, the screwing amount of the spring retainer 57 is obtained, and the inclination angle θ of the inclined surface 56b of the ring spring 56 at this time is defined as the set angle θstd.

However, actually, instead of measuring the inclination angle θ, the following distance difference Δd was measured, and this was used instead of the inclination angle θ. That is, as shown in FIG. 1, a predetermined inner circumferential position P
in and a predetermined outer peripheral position Pout, a reference surface S1 is provided at a position facing the ring spring 56, and a distance din (a first distance of the present invention) between the reference surface S1 and a predetermined inner peripheral position Pin;
And a distance dou between the reference plane S1 and a predetermined outer peripheral position Pout.
t (the second distance of the present invention) was measured. The reference surface S1 is provided so as to be substantially perpendicular to the rotation axis 51. Since the interval between the inner peripheral position Pin and the outer peripheral position Pout is constant, the difference Δd (= din−dout) between the distance din and the distance dout is equal to the inclination angle θ.
Is proportional to For this reason, the difference Δd of this distance
Was used instead of. In addition, the aforementioned set angle θ
The difference △ d of the distance corresponding to std is △ dstd.

Next, the diagnostic jig used in this embodiment will be described. FIG. 2 is an explanatory view of a diagnostic jig, and FIG.
Is a front view, and (b) is a plan view. The diagnostic jig 10
As shown in FIG. 1 and FIG.
1, a pair of rails 12, 12 extending in the diameter direction of the cylinder 11, and rectangular parallelepiped moving blocks 13, 13 slidably mounted on the rails 12, 12. And barrier blocks 14, 14 for preventing the moving blocks 13, 13 from coming off the rails 12, 12. Of these, the moving block 13
Is for mounting the micrometer 15.

Using this diagnostic jig 10, a flashover diagnosis was performed. FIG. 3 is a diagram viewed from A in FIG. 9 (that is, a diagram when the DC motor is viewed from the ring spring side). On the inclined surface 56b of the ring spring 56 shown in FIG.
Two measurement points A, A ', B, B' were determined. Since a varnish is usually applied to the inclined surface 56b of the ring spring 56 for electrical insulation, the varnish was removed at each measurement point before measuring the distance. This is because the micrometer 15 measures the distance in a state where the tip of the spindle 15a is in contact with the object to be measured, and when the measurement is performed without removing the varnish, the measurement includes the thickness of the varnish, but in this case, This is because variations in the thickness of the varnish appear as errors and sufficient accuracy may not be obtained.

Subsequently, as shown in FIG.
Attach the micrometer 15 to the moving block 13 0, insert the tube 11 to the rotary shaft 51 of the DC motor 50, two micrometers 15, 15 measurement points A,
A ′ (see FIG. 3) was set so as to be opposed. Also,
A fixing bracket 16 was interposed between the barrier block 14 and the outer edge of the movable clamper 55. In this state,
The trajectory drawn by the tip of the spindle 15a of the micrometer 15 when the moving block 13 is slid along the rail 12 corresponds to the aforementioned reference plane S1. FIG.
FIG. 3 is a perspective view when the diagnostic jig 10 is attached to the DC motor 50.

Next, as shown in FIG. 1, the distance din from the reference plane S1 to the inner peripheral position Pin is measured at one measurement point A (see FIG. 3) by one micrometer 15,
Thereafter, the moving block 13 is moved to the outer peripheral side, and the reference surface S
The distance dout from 1 to the outer peripheral position Pout was measured. The measurement point A ′ is measured by the other micrometer 15.
Measure the distance din from the reference surface S1 (see FIG. 3) to the inner peripheral position Pin, is then moved to move the block 13 to the outer peripheral side, the distance dout from the reference plane S1 to the peripheral position Pout was measured.

The distance is measured by the micrometer 15 by rotating a screw (not shown) of the micrometer 15 to bring the tip of the spindle 15a into contact with the inner peripheral position Pin or the outer peripheral position Pout to be measured. This was done by reading the scale. Subsequently, with the cylinder 11 of the diagnostic jig 10 inserted into the rotary shaft 51, the diagnostic jig 10 is rotated by 90 ° around the rotary shaft 51, and the two micrometers 15 , B ′ (see FIG. 3). Then, in the same manner as above, the distances din and dout at the measurement points B and B 'were measured.

Next, the four measurement points A, A ', B,
The distance difference Δd is calculated for each of B ′, and if any of the distances Δd is incorrect (for example, does not match Δdstd or deviates from the allowable range considered to be equivalent to Δdstd) In this case, it is diagnosed that the flashover may occur because the ring spring 56 is loose, and the spring retainer 57 is further tightened so that its Δd becomes appropriate (for example, it is made equal to Δdstd). Or within the above-mentioned allowable range). On the other hand, when Δd was appropriate, it was diagnosed that there was no possibility that flashover would occur.

Thereafter, the varnish was applied again to the place where the varnish was peeled off and dried for about 2 days. When this DC motor 50 was reused, the probability of occurrence of flashover was reduced. According to the above embodiment, the following effects were obtained. That is, by measuring the looseness of the ring spring 56, the occurrence of flashover could be prevented beforehand, and the life of the DC motor 50 could be extended.

In addition, since the difference Δd in the distance between the inclined surfaces 56b of the ring spring 56 was measured instead of measuring the inclination angle θ, the measuring operation was relatively simple. Further, since measurement was performed at four measurement points A, A ', B, and B' to determine whether or not flashover might occur, the accuracy of the diagnosis was higher than in the case where only one measurement point was provided. Was.

The accuracy of diagnosis may be further improved by performing measurement at more locations, but in that case, the number of locations where the varnish is to be removed increases, and the time required for the operation of removing the varnish increases. [Second Embodiment] The second embodiment relates to a method for diagnosing the occurrence of flashover of a DC motor using an eddy current displacement sensor and a diagnostic jig. FIG. 5 is an explanatory view of the diagnosis method of the present embodiment, and FIG. 6 is an enlarged view of a main part of FIG.

In the second embodiment, as shown in FIG. 5, the reference surface S2 is formed so that the angle between the reference surface S2 and the rotation shaft 51 becomes the set angle θstd, in other words, the inclined surface 56b of the ring spring 56.
It was provided so as to be substantially parallel to. In this case as well, as shown in FIG. 6, similarly to the first embodiment, the inner peripheral position Pin from the reference plane S2.
The difference ΔD (= Din−Dout) between the distance Din (the first distance of the present invention) and the distance Dout (the second distance of the present invention) from the reference plane S2 to the outer peripheral position Pout is determined by the inclination angle θ. Proportional. Therefore, the difference ΔD in the distance is used instead of the inclination angle θ. The difference ΔD of the distance corresponding to the set angle θstd is set to ΔDstd.

Next, the diagnostic jig used in this embodiment will be described. FIG. 7 is an explanatory view of the diagnostic jig, and (a)
Is a front view, and (b) is a bottom view. As shown in FIGS. 5 and 7, the diagnostic jig 20 used in this embodiment includes a cylindrical body 21 that can be inserted into a rotating shaft 51 of a DC motor 50, and an arm 22 that extends in a diameter direction of the cylindrical body 21. , 22 and substantially L-shaped sensor support portions 23, 23 screwed to the arms 22, 22, respectively.

The cylindrical body 21 is provided with a knurl for smooth sliding on the peripheral surface, and a lid 21a which is in contact with the upper end of the rotating shaft 51 is screwed to the upper surface thereof. In addition, each sensor supporting portion 23 is provided at the position facing the inner peripheral position Pin and the outer peripheral position Pout on the inclined surface 56b of the ring spring 56, respectively, at the positions corresponding to the eddy current displacement sensors 24, 24 (for example, EX- trade name manufactured by KEYENCE CORPORATION). 500 series). The lower surface (reference surface S) of this sensor support 23
In 2), the angle formed by the rotating shaft 51 substantially matches the set angle θstd, and the eddy current displacement sensors 24, 24 are arranged side by side on this lower surface.

That is, the two eddy current displacement sensors 24, 2
The arrangement direction of 4 substantially coincides with the inclination direction of the inclined surface 56b of the ring spring 56. Thus, the eddy current displacement sensor 2
The reason why the direction of arrangement of the eddy current displacement sensors 4 and 24 is substantially coincident with the direction of inclination of the inclined surface 56b is that the eddy current displacement sensor generally has a small measurable range of 0 to several mm. In such a case, one of the eddy current displacement sensors may not be able to measure.

Using this diagnostic jig 20, a flashover diagnosis was made. FIG. 8 is an apparatus configuration diagram when the diagnostic jig of this embodiment is attached to a DC motor. FIG.
As shown in (1), eddy current displacement sensors 24, 24 are attached to the sensor support portion 23 of the diagnostic jig 20, the cylinder 21 is inserted into the rotating shaft 51 of the DC motor 50, and the lid 21a abuts on the upper end of the rotating shaft 51. Was set as follows. Then, each eddy current displacement sensor 24 is connected to the personal computer 2 via a displacement meter 26.
7 was connected. The personal computer 27 obtains the difference ΔD from the distances Din and Dout at various measurement points of each eddy current displacement sensor 24 based on a processing program recorded in a built-in memory and displays the difference on a display. It is.

In this device configuration, the operator can use the keyboard of the personal computer 27 to move the distance Di at the measurement point.
Command the start of measurement of n and Dout, and display △ D
Was displayed. Subsequently, in a state where the cylinder 21 of the diagnostic jig 20 is inserted into the rotation shaft 51, the operator moves the diagnostic jig 20.
A finger is placed on a knurl provided on the peripheral surface of the cylindrical body 21 of the cylinder 21 to slightly move the diagnostic jig 20 around the rotation axis 51 (for example, 45).
In this state, a command to start measuring the distances Din and Dout at the measurement points was issued from the keyboard of the personal computer 27, and ΔD was displayed on the display. Then, such measurement was repeatedly performed, and the difference ΔD of the distance was obtained at a plurality of (for example, eight) measurement points over the entire inclined surface 56 b of the ring spring 56.

In any of the plurality of measurement points, when ΔD is inappropriate (for example, when ΔDstd does not match, or when the ΔDstd deviates from the allowable range considered to be equivalent to Dstd). In this case, it is diagnosed that flashover may occur because the ring spring 56 is loose, and the spring retainer 57 is retightened so that its ΔD becomes appropriate (for example, it is matched with ΔDstd, or Within the acceptable range). On the other hand, when ΔD was appropriate, it was diagnosed that there was no possibility that flashover would occur. When this DC motor 50 was reused,
The probability of a flashover occurring has been significantly reduced.

According to this embodiment, the following effects are obtained in addition to the effects of the first embodiment. That is, the ring spring 5
Measurement was performed at a plurality of measurement points over the entire circumference of No. 6, and it was diagnosed whether or not a flashover might occur, so that the accuracy of the diagnosis was further improved.

When measurement is performed at a plurality of measurement locations over the entire circumference of the ring spring 56, the diagnostic jig 20 rotates around the rotation shaft 51 with the lid 21a abutting on the upper end of the rotation shaft 51. The surface S2 is a diagnostic jig 2
Even when 0 was rotated, it was kept at a constant angle (θstd) with respect to the rotating shaft 51. For this reason,
High measurement accuracy was always achieved at each measurement point.

The vortex which is a non-contact type distance measuring device as in the second embodiment is different from the case where the distance is measured by the micrometer 15 which is a contact type distance measuring device as in the first embodiment. Since the distance was measured by the current displacement sensor 24, it could be measured quickly. In particular, the eddy current displacement sensor 24
Does not measure the thickness of the varnish even if there is a varnish on the inclined surface 56b of the ring spring 56, and measures the distance to the metal. The work of reapplying and drying the varnish is no longer required, and the working time is greatly reduced, and the measurement itself is greatly simplified. Therefore, the DC motor 50
Diagnosis and repair could be carried out on the line where the inspection work was performed as a line work. Specifically, in the first embodiment, it took about 50 minutes to complete the measurement, whereas in the second embodiment, it took about 5 minutes, which was about 1/10. In the first embodiment, it is necessary to reapply and dry the varnish after the measurement is completed. In view of this work time, the second embodiment is more advantageous.

Further, since the eddy current displacement sensors 24, 24, which are distance measuring devices, are provided at positions opposed to the inner peripheral position Pin and the outer peripheral position Pout of the ring spring 56, the distance measuring device is provided as in the first embodiment. No need to slide,
Individual differences (errors) between operators have been reduced, and measurement accuracy has been improved. Whereas in particular the first example was accuracy 1/100 mm second embodiment precision 1/1000 Mi
It became ri .

The embodiments of the present invention are not limited to the above-described embodiments, and it goes without saying that various embodiments can be adopted as long as they fall within the technical scope of the present invention.
For example, an eddy current displacement sensor 24 may be mounted on the moving block 13 instead of the micrometer 15 of the diagnostic jig 10 of the first embodiment. Alternatively, a micrometer 15 may be attached instead of the eddy current displacement sensor 24 of the diagnostic jig 20 of the second embodiment.

Further, the number of rails 12 of the diagnostic jig 10 of the first embodiment may be increased to three or more, and the moving blocks 13 and the like may be increased accordingly. It may be reduced to one. Similarly, the number of the arms 22 of the diagnostic jig 20 of the second embodiment may be increased to three or more, and the sensor support 23 and the like may be increased accordingly.
Conversely, the number of arms 22 may be reduced to one.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a diagnosis method according to a first embodiment.

FIG. 2 is an explanatory view of a diagnostic jig of the first embodiment;
(A) is a front view, (b) is a plan view.

FIG. 3 is a diagram viewed from A in FIG. 9;

FIG. 4 is a perspective view when the diagnostic jig of the first embodiment is attached to a DC motor.

FIG. 5 is an explanatory diagram of a diagnosis method according to a second embodiment.

FIG. 6 is an enlarged view of a main part of FIG. 5;

FIG. 7 is an explanatory view of a diagnostic jig according to a second embodiment;
(A) is a front view, (b) is a bottom view.

FIG. 8 is a device configuration diagram when the diagnostic jig of the second embodiment is attached to a DC motor.

FIG. 9 is an explanatory diagram of a DC motor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Diagnostic jig, 11 ... Cylinder, 12 ... Rail, 13 ... Movable block, 14 ... Wall block, 15 ... Micrometer, 16 ... Fixing bracket , 20 ... jig for diagnosis, 21 ... cylinder, 21a
..Lid, 22 ... arm, 23 ... sensor support part,
24: Eddy current displacement sensor, 26: Displacement meter, 27
... PC, 50 ... DC motor, 51 ... Rotary axis, 52 ... Fixed clamper, 53 ... V mica,
54 ... commutator, 55 ... movable clamper, 56 ...
・ Ring spring, 56b ・ ・ ・ Slope, 57 ・ ・ ・ Spring presser, Pout ・ ・ ・ Outer peripheral position, Pin ・ ・ ・ Inner peripheral position, S
1, S2: reference plane, θ: inclination angle, θstd
・ Set angle.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yasuhiro Tanaka 1-1-4 Meieki Station, Nakamura-ku, Nagoya City, Aichi Prefecture Tokai Passenger Railway Co., Ltd. (56) References JP-A-51-99206 (JP, A) JP-A-52-125705 (JP, A) JP-A 50-96903 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02K 11/00 H02K 13/00

Claims (9)

(57) [Claims] 1. A fixed clamper that is fixed to a rotating shaft and rotates with the rotating shaft, and is provided movably in the axial direction of the rotating shaft, and is capable of pressing and holding a commutator together with the fixed clamper via an insulating material. A movable clamper, a ring spring made of spring steel abutting on a side of the movable clamper opposite to a side that presses and clamps the commutator, and a spring that presses an inner peripheral side of the ring spring toward the movable clamper. (1) a method of diagnosing a DC motor having a presser, comprising: (1) regarding a tilt angle formed by a surface of the ring spring opposite to a side abutting on the movable clamper with respect to the rotation axis; The inclination angle when the inner peripheral side of the ring spring is pressed with a predetermined pressing force by a spring retainer is determined in advance as a set angle, and (2) the inclination angle after the DC motor is actually used is determined. And (3) determining whether or not flashover occurs by comparing the set angle with the measured inclination angle. 2. A reference surface opposing a surface of the ring spring opposite to a surface abutting on the movable clamper,
Determine a predetermined inner circumferential position and a predetermined outer circumferential position on the same radial direction of the ring spring, measure a first distance from the inner circumferential position to a reference surface, and a second distance from the outer circumferential position to a reference surface, The diagnostic method for a DC motor according to claim 1, wherein a difference between the first distance and the second distance is treated as the inclination angle. 3. The method for diagnosing a DC motor according to claim 1, wherein an eddy current displacement sensor installed on the reference plane is used when measuring the first distance and the second distance. 4. The method for diagnosing a DC motor according to claim 3, wherein the eddy current displacement sensor is provided at a position facing each of the inner peripheral position and the outer peripheral position. 5. The diagnostic method for a DC motor according to claim 3, wherein an angle between the reference plane and the rotation axis substantially matches the set angle. 6. A fixed clamper that is fixed to a rotating shaft and rotates with the rotating shaft, and is provided so as to be movable in the axial direction of the rotating shaft, and can press and pinch a commutator together with the fixed clamper via an insulating material. A movable clamper, a ring spring made of spring steel abutting on a side of the movable clamper opposite to a side that presses and clamps the commutator, and a spring that presses an inner peripheral side of the ring spring toward the movable clamper. A jig for diagnosing the DC motor, comprising: a reference surface facing a surface of the ring spring opposite to a surface in contact with the movable clamper; and a jig installed on the reference surface. An eddy current displacement sensor for measuring a distance from the reference surface for each of a predetermined inner circumferential position and a predetermined outer circumferential position of the ring spring on the same radial direction, Use jig. 7. The diagnostic jig for a DC motor according to claim 6, wherein the eddy current displacement sensor is provided at a position facing each of the inner peripheral position and the outer peripheral position. 8. The jig for diagnosing a DC motor according to claim 6, wherein an angle formed between the reference plane and the rotation axis substantially coincides with a predetermined set angle. However, the set angle is an angle of inclination of the surface of the ring spring on the side opposite to the side in contact with the movable clamper with respect to the rotation axis. The angle when the inner peripheral side of the ring spring is pressed. 9. A cylinder which is slidably supported around the rotation axis while being inserted into the rotation axis by a predetermined length, and wherein the reference surface is provided integrally with the cylinder. The diagnostic jig for a DC motor according to any one of claims 6 to 8, wherein: