JPS5956847A - High bar monitor for commutator - Google Patents

Abstract

PURPOSE:To prevent abnormal deterioration in commutation and serious accidents for a commutator by providing a vibration acceleration sensor mounted on a brush sliding on the commutator and a comparator for comparing the measured value with a set reference value, thereby detecting the production of a high bar of the commutator. CONSTITUTION:A vibration acceleration sensor 5 is mounted on the vibration detecting brush 4 sliding on a commutator 1, the vibration acceleration waveform detected by the sensor 5 is inputted to a charging amplifier 7 to the level readily processed thereafter. The magnitude of the pulse of this vibration is compared by a comparator 10 in magnitude of the value of the vibration acceleration to become the reference set in advance obtained on a normal commutator. When the acceleration larger than the reference value is detected, the presence of the high bar is warned by an alarm unit 11 by driving a bell or lighting a lamp. In this manner, the deterioration of the commutation and serious accident can be prevented in advance.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention is a rotating electric machine having a commutator that slides on a commutator brush. This article relates to a commutator monitoring device.

[Technical background of the invention and its problems]

The commutator is an important part of DC motors and other rotating electric machines, and any defects therein will lead to poor contact with the brushes, resulting in worsening of current flow.

Therefore, although it is manufactured to be free of hyper and imitation, centrifugal force during operation causes deflection of the commutator segments, and thermal elongation of the commutator segments due to high temperatures causes deflection of the commutator segments. cause

Since these deflections are repeatedly applied during operation, over time they cause the occurrence of -.

Conventionally, in order to investigate the presence or absence of this nozzle, during periodic inspection of a rotating electrical machine, as shown in Figure 1, a dial indicator 2 is placed on the outside of the commutator I, the commutator is slowly twisted, and the current Hyper 3 was detected by reading the dial indicator. However, with this method,
During normal operation, it is impossible to detect −・i・gu−.
If the hyper is progressing abnormally between periodic inspections, there is a possibility that serious accidents may occur due to deterioration of rectification. For this reason, the machine can be operated without stopping.
There was a request to be able to detect the occurrence of a hypertrophy and monitor its progress.

[Purpose of the invention]

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to detect the occurrence of impurity during operation, monitor its progress, and prevent abnormal deterioration of commutation and serious accidents.
The purpose is to provide an iper monitoring device.

[Summary of the Invention] In order to achieve the above object, the present invention provides a vibration acceleration sensor, such as a brush that slides on a commutator, and a comparator that compares the value measured by the sensor with a reference set value. It is composed of

Embodiments of the present invention will be described below with reference to FIG.

In Figure 2, 1 is the commutator, and 3 is the ・ that occurred on the commutator.
・Iper, 4 is a vibration detection brush that slides on the commutator, 5
is a vibration acceleration sensor installed on the brush 4, 6 is a cable that transmits the output signal of the vibration acceleration sensor, and 7 is a cable that amplifies the entire signal of the vibration acceleration sensor to a level that facilitates subsequent signal processing. Charso amplifier 8 is an isolation amplifier; 9 is an at-pass filter that filters only the high frequency component of the signal; 10 is a preset standard vibration acceleration value and a vibration acceleration value detected by vibration acceleration sensor v5; 11 is a comparator that compares the magnitude of the vibration acceleration, and when a vibration acceleration larger than the standard vibration acceleration is detected, an alarm is output by driving a bell or lighting a lamp to notify the outside of the presence of I-G. . During operation, current flows through the commutator, so the vibration detection brush 4 is connected to the vibration acceleration sensor 5. It is necessary to take measures to prevent the current from passing through the cable 6 and reaching the ground. For this reason, the vibration detection brush 4 and the vibration acceleration sensor 5 are constructed as shown in FIG. 3. In FIG. 3, 4a is a part that slides on the commutator, and is made of carton material like the commutator brush. 4b is an insulating material such as Bakelite to cover the acceleration sensor 5, and is further covered with silicone rubber 4C so that the carzene powder generated from the brush will land on the acceleration sensor 5 and will not be electrically conductive to the ground.

Next, the operation of the commutator monitoring device configured as described above will be explained.

The vibration acceleration waveform detected by the vibration acceleration sensor 5 passes through the brush 4, but reflects the unevenness of the commutator surface and becomes as shown in FIG. 4(a). This cell 7 is generated when the commutator bar passes the brush 4, and is called a commutator bar passage vibration. The magnitude of the noise of this vibration waveform is
Without −・I・G−, the value would be almost the same as in Figure 4 (
It is like a), but when a hyper occurs, the fourth
A vibration waveform as shown in Figure (b) is obtained. In the same figure, the /F pulse at 13a is due to normal passage of the commutator piece, and the No/F pulse at 13b is due to hyper passage. This 13b
Since the magnitude of the /'P pulse of By comparing with the standard vibration acceleration value selected based on the magnitude of the obtained
By detecting the occurrence of IPA and knowing its progress, it is possible to monitor the progress of IPA.

The embodiments described above are effective for a rotating electric machine that is operated at a constant rotational speed, but problems arise when the rotating electrical machine is used with a variable rotational speed. That is, the fourth
As shown in Figure (a), the magnitude of the vibration passing through the commutator is
As shown in FIG. 5, it increases with the number of rotations. Therefore, it is expected that a simple comparison of the acceleration vibration value with the reference value as in the above-described embodiment may result in an erroneous determination.

FIG. 6 shows an embodiment considered to be suitable for a variable speed machine. In FIG. 6, l.

3.4, 5, 6, 7, 8, 9.11 have the same functions as the embodiment shown in FIG. 2, except that I4 is a peak value detector that detects the peak value of the vibration acceleration waveform, and I5 is the vibration acceleration waveform. Operator 9 calculates the effective value of 16 is 14', a divider receives the signal from I5 and calculates the peak value/effective value, 10 is the magnitude of the peak value/effective value that is a preset reference Sato 16
This is a comparator that compares the magnitude of the peak value/effective value obtained.

In this embodiment, the presence or absence of a hyper can be determined based on the magnitude of the peak value/effective value for the following reason. That is, both the peak value and the effective value, which express the magnitude of the vibration acceleration waveform, have the characteristic that they increase at the same rate with respect to the rotational speed as shown in FIG.

Therefore, the peak value/effective value does not change even if the rotational speed changes. However, if hyper occurs from a woman, the -1 value increases rapidly, but the effective value does not increase that much, so
Peak value/effective value increases significantly. Therefore, by monitoring this increase, it is possible to obtain a commutator high-speed monitoring device that is also suitable for variable speed machines.

Note that the present invention is not limited to the above-mentioned embodiments. For example, in place of the insulating silicone rubber 4C in FIG. 3, synthetic resin or the like may be used as long as it has insulating properties to obtain the same effect. You can print it! The same effect can be obtained by using a material with good sliding properties such as Teflon instead of the + case 4a. Other modifications may be made without departing from the gist of the present invention.

〔Effect of the invention〕

As described above, according to the present invention, the unevenness of the commutator of a rotating electric machine is detected as a photographed acceleration signal by a vibration detection brush installed with a vibration acceleration sensor, and the magnitude of this vibration is used as a reference setting value. In variable speed IW machines, the magnitude of the peak value/effective value of the vibration acceleration waveform is compared with the reference set value, so the occurrence of commutator hyper is detected correctly and early. The 7 points of the commutator can prevent worsening of poor commutation and serious accidents.
It is possible to provide an advanced bill viewing device.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional method for detecting a commutator, and FIG. 2 is a schematic configuration diagram showing an implementation of a commutator monitoring device 511 according to the present invention. Figure 3 shows the same implementation 1.
Figure 4 is a diagram showing the configuration of an example vibration detection bra/acceleration sensor, and Figure 4 is a vibration acceleration waveform diagram obtained from the vibration acceleration sensor in Figure 2. ) Characteristic curve diagram of acceleration waveform magnitude versus rotational speed. FIG. 6 is a schematic diagram showing another embodiment of the commutator nozzle monitoring device of the present invention suitable for a variable speed machine. l...Commutator, 2...Guyarquezo, 3...
4. Vibration detection brush, 5. Vibration acceleration sensor, 6. Cable, 7. Charge amplifier,
8...Isolated amplifier, 9...No1 Inoya Sufu<)Ref-
, 10... Comparator, 1... Comparator, I4... Peak value detector, 15 Effective value calculator, I6 - W divider. Applicant's agent Patent attorney Suzu W. Takehiko Figure 1 Figure 2 Figure 3 Figure 4 (U)

Claims (4)

[Claims] (1) A commutator consisting of a rotating electric commutator, a vibration acceleration sensor mounted on a sliding brush, and a comparator that compares the magnitude of the vibration value measured by this vibration acceleration sensor with a reference setting value. ...Ibar monitoring device. (2) The comparator compares the magnitude of the vibration value measured by the vibration acceleration sensor and the magnitude of the peak value of the captured waveform with a predetermined threshold value. Commutator hyper-monitoring device as described in Section 1. (3) Claims characterized in that the comparator compares the ratio of the magnitude of the peak value of the captured waveform measured by the vibration acceleration sensor to the magnitude of the effective value with a predetermined threshold value. A commutator monitoring device according to item 1. (4) The commutator temperature monitoring device according to claim 1, wherein the vibration acceleration sensor is electrically insulated from the commutator.