JPS59195108A - Method and device for inspecting gouge on gear - Google Patents

Abstract

PURPOSE:To discriminate the presence or absence of any gouge on each gear from the magnitude in the dded output by intermeshing all multishaft intermeshing gear trains, rotating the same, detecting oscillation signals, extracting gouge signals and adding the gouge signals in synchronization respectively with the reference signals for the respective shafts. CONSTITUTION:The oscillation signal A for the entire part is inputted to a gouge signal extracting part 50, which outputs a gouge signal E. The signal E is inputted to each of adders 61-63. On the other hand, reference signals B-D are inputted respectively separately to the adders 61-63, by which all the gouge signals are subjected to addition in synchronization with the respectively separate reference signals. The added output from the adder to which the reference point signal of the gouged gear is applied has an extremly large increase rate than the added outputs from the other adders. If, therefore, the added output in a specified time is compared with a prescribed level value and whether the value exceeds the same or not is identified, the presence or absence of the gouge is known. If the generating source for the reference point signal applied to the adder exceeding the level value is investigated, it is knwon that the gear attached to such shaft is the gouged gear.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for directly inspecting each gear of a multi-shaft meshing gear system for the presence or absence of dents.

Multi-shaft meshing gear systems are widely used in power transmission elements such as vehicle transmissions, but during the gear manufacturing process, the tooth surfaces may collide with the processing machine due to accidental reasons, or the gears may overlap. Collisions often result in bumps (irregularities) on the tooth surface.

Even if these dents are as small as a few micrometers, if they are present on the meshing surface, they will cause a large amount of noise. Therefore, 2. For example, in the gear system of an automobile, in order to exclude gears with dents.

All gears used in the first gear are inspected for dents.

Now, as a method for inspecting dents, first of all, visual inspection using optical magnification means is simple, but the inspection efficiency is poor and dents are easily overlooked. Therefore, a method of evaluating the noise itself has been proposed, in which a master gear and a gear to be inspected are meshed and rotated, and a skilled inspector intuitively evaluates the sound generated at that time. but.

This test result is problematic in that it depends on the skill level of the tester. As a way to improve this, attempts have been made to convert the generated sound into an electrical signal using a microphone, extract it, and evaluate the power of the entire band of the signal, or the power of a specific frequency component extracted by frequency analysis of the signal. However, there are noise components of the same type in the surrounding area, and the sound generated by the dents is often buried in these noise components, making it difficult to extract the sound sufficiently, and the accuracy of judgment is not necessarily improved compared to that of experienced inspectors. do not have.

By the way, at the moment when the dents on the tooth surface of the gear to be inspected come into contact with the tooth surface of the master gear, a shocking meshing state occurs, and as a result, vibrations are generated in the meshing gear system. To consider this condition.

If there are no dents, steady vibration is occurring, which is a combination of drive source vibration, bearing vibration, etc.; however, if there are dents, high vibrations equivalent to the natural frequency of both vehicle systems are occurring. vibrations of large numbers and large amplitudes occur. The two are then combined into a single vibration to form the overall vibration, but within that vibration, the signal from the dent is clearly distinguishable.

Focusing on this, one of the applicants first proposed the following.

The gear to be inspected is meshed with the tooth surface of an intact master gear and rotated, and during this time the vibration signal is detected and the signal component caused by the dents is extracted from it.

We proposed an inspection method for determining the presence or absence of dents by comparing their sizes (Japanese Patent Application No. 157,783/1983). Figure 1 shows
The vibration detector 7, which is the dent signal extraction part, is attached to the bearing part that supports the support shaft of the gear to be inspected, and first, its detection output is sent to the amplifier 51.

After being amplified by an appropriate magnification, the signal is sent to a filter circuit 52 to separate relatively high frequency components including frequency components caused by dents, which have been determined experimentally in advance. Note that if the dent is large enough, it is possible to determine the presence or absence of the dent from only this separated high-frequency component, but in the case of a minute dent, it is difficult to distinguish between other frequency components. There are many things. Therefore, in the secondary stage, the output of the filter circuit 52 is sent to the rectifier circuit 53 to form a full-wave rectified signal, and then,
An envelope detection circuit 54 consisting of a low-pass filter etc.
The envelope signal of the full-wave rectified signal is then reshaped. In this way, in the output of the filter circuit 52, the steady vibration component is almost smoothed by full-wave rectification, and then by the envelope shaping, it becomes almost a horizontal line (DC component) (!:
As a result, sudden frequency components caused by the dents are extracted in order of priority. Figure 2 shows an example of the waveform of the extracted signal component.The vibration signal (A) is detected for a dent that is difficult to identify using the noise evaluation method described above, and the dent signal (RO) is clearer than the above processing. ) is extracted.

In the above inspection method, the gear to be inspected is meshed with the master gear and dents are inspected, and in order to inspect all the gears in a multi-shaft meshing gear system, it is necessary to inspect several gears. The number of times is required.

In order to reduce the number of inspections, it is possible to perform the inspection by directly meshing the two gears to be inspected, but in this case, even if there is a dent in either of the gears to be inspected that mesh, the dent signal will be extracted. Therefore, even if a dent signal is obtained, it is essential to determine which gear to be inspected has a dent. In addition, since the machining accuracy of the gear to be inspected is generally lower than that of the master gear, two types of vibrations occur when the gears to be inspected mesh with each other, resulting in a decrease in the S/N ratio when extracting the dent signal. is also unavoidable.

Moreover, the multi-shaft meshing gear system 9 example is each gear a on the three axes of A-0.
Considering the meshing test for ~C, it is necessary to inspect gears a, b and C at least twice, and if dents are detected in both of these two inspections, then gears a and C must be inspected at least twice. In the end, the number of inspections is the same as the inspection using the master gear.

Now, let's consider solutions to each of the above problems.

The dent signal is generated when teeth with dents mesh together.
After all, the dent signal is generated at a specific rotational angle position for one rotation of the gear, and by using this, if the dent signal is generated at a constant period, it is possible to determine the dent quality. This means that the gears can be identified.

Based on the results of the above studies, the present invention aims to provide a method and apparatus for performing dent inspection on each gear of a multi-shaft meshing gear system with a small number of inspections and with high inspection accuracy. .

First, the invention of the method will be explained.

Rotation is transmitted by each gear to be inspected: a driving gear with a different number of teeth, at least one intermediate gear, and a driven gear, and the overall vibration signal is detected from one of the rotating shafts of each gear, and all vibration signals are detected from among the vibration signals. The signal component caused by the dents is extracted, the reference point signal of each gear is separately detected, and the signal component due to the dents is added in synchronization with each reference signal separately, and the signal due to the dents is accumulated for each gear with dents. The amplitude becomes large,
As a result, the presence of the gear with dents is made clear.

Furthermore, what is meant by "synchronized addition" mentioned above?

The method is to start from the generation position of the reference point signal and sequentially add signal components when the gear to be inspected rotates by the same angle.

Therefore, in a constant speed rotation state, the result is the same as that of sequentially adding signal components at the time when a predetermined period of time has elapsed using the generation time of the reference point signal as a starting point.

Two more detailed explanations of the present invention include fixing a gear to be inspected to a rotating shaft connected to a drive source and using it as a drive gear;
The drive gear is meshed with another gear to be inspected to make it an intermediate gear, and the intermediate gear is further meshed with another gear to be inspected to make it the first drive gear, and these have different numbers of teeth as usual. It is something. By driving the drive source, the driving gear, intermediate gear, and driven gear enter a rotation transmission state.

During this rotation transmission, vibration is generated when the tooth surfaces of each gear mesh with each other. During rotation, when the tooth surface with a striking effect comes into contact with the tooth surface of the mating partner, it will be in a state of one-sided contact, which is similar to a striking state, so a relatively high frequency corresponding to the natural frequency of this tooth row will be generated. A vibration component is generated, which has a different frequency and amplitude from the steady vibration.

The vibration component and steady vibration caused by the dents are transmitted as overall vibrations to the rotating shaft of the gear via the meshing gear, and further transmitted to the bearing portion and the like.

Therefore, the second step is to attach a vibration detector to an element that transmits vibrations and is always in a stationary state, such as the bearing of the intermediate gear, and convert the vibration transmitted thereto into an electrical vibration signal. Take it out. As a result, the entire vibration signal including the signal component corresponding to the vibration caused by the dent is extracted.

During this time, on each of the gears at the same time.

An arbitrary reference point on the rotating part is selected, and a mark attached thereto and a stationary mark detector placed opposite the reference point generate a signal each time the mark passes. As a result, a reference point signal indicating that the reference point of each gear passes through each predetermined position is extracted. This reference point signal corresponds to the rotational speed p4 of each gear, and since the rotational speed of each gear is different, the generation timing of the reference point signal is different from each other.

A signal component due to a dent is extracted from the vibration signal in the same manner as described above. The vibration signal from the extracted dent is @
All of them are generated as protruding signals over time, depending on the dents that exist on the gear. If there is only one dent on any of the gears, a corresponding signal will be generated, and this will occur at regular intervals, or depending on the occurrence of this signal, which one of the gears will have the dent. It is unknown whether it exists. Further, if there are multiple dents, the signal due to the dents is a plurality of croup, and each croup is generated at the same cycle as the rotation period of the gear having the dents. However, it is not possible to immediately determine the period of each group's signals from a signal obtained by combining the signals of each group.

Therefore, in order to determine which gear's rotation period matches the signal caused by the dent, the presence or absence of synchronization with the reference point signal of each gear is checked.

In other words, an adder is attached to each gear, all signal components are introduced into each adder, the reference point signal of each gear is applied to each adder as a synchronous addition command, and only the synchronized signals are input to each adder. Add.

In FIG. 3, A is the overall vibration signal.

B, O, and D are reference point signals for each gear, and the overall vibration signal A is input to the dent signal extraction section 50 (the circuit already described in FIG. 1), which outputs the dent signal E, and The trace signal E is input to each of adders 61-63. On the other hand, the reference point signals B, O, and D are input to adders 61 to 63 separately. Each of the adders 61 to 63 adds all the dent signals in synchronization with the respective reference point signals.

In other words, for each rotation of each gear, each group is
In the adder to which the reference point signal is applied as a synchronous addition command, signal components at the same rotational angular position are accumulated for one rotation of the gear.

For example, if there is a dent on gear a, the dent signal is accumulated. This dent signal is also input to the adder of the gear b, but it is asynchronous with the reference point signal of the gear and is not accumulated in the adder of the gear. This relationship is the same no matter which gear has dents, and the adder for the gear with dents accumulates, but the other adders do not.

Therefore, the addition output of the adder to which the reference point signal of the dented gear is applied has an extremely low increase rate compared to the addition output of other adders.

By comparing the addition output for a certain period of time or number of rotations with a predetermined level value and seeing whether it exceeds it, you can tell whether there is a dent or not. Looking at the source of the point signal reveals that the gear attached to the shaft is a gear with dents.

Next, the invention of an apparatus for implementing the method will be described below. This invention is designed to accurately obtain the overall vibration signal and the reference signal from each gear, and a driving gear, at least one intermediate gear, and a driven gear are supported in mesh by a rotating shaft on two machines. A vibration detector is attached to the support of one of the rotating shafts, and a mark is placed on each rotating shaft.
A mark detector is placed on the machine stand facing it, and the overall vibration signal is taken out from the vibration detector, and each reference point signal is taken out from the mark detector.

An embodiment of the invention will be described with reference to FIG.

In this embodiment, in order to inspect a large number of gears to be inspected, the gears are made detachable from the rotating shaft, and the intermediate gears are made slidable relative to other gears. To further explain, the two removable means are such that the gear is not directly fixed on the rotating shaft but can be easily attached and detached through other means, and the intermediate gear is wider than the other gears, so that the gear can be easily attached and detached over its entire width. It was designed to inspect the marks.

In FIG. 4, drive shaft systems 10. Intermediate shaft system 20. This is a load shaft system 30. In the drive shaft system 10, a HjiX drive shaft 11 is rotatably supported by a bearing 13, one end of which is connected to the rotating shaft of the drive shaft 12, and a gear a is connected to the other end.
is removably attached.

Although not shown in the figure, the end of the drive shaft 11 is a shaft with a small diameter. A rotating shaft 14 is placed on the extension of the drive shaft 11, and a rotating shaft 14 is placed on the end thereof with a chuck portion made of a tapered cylindrical body with an inner diameter smaller in diameter than the small diameter shaft, and a bearing supports the rotating shaft 14. 15 is loosely engaged with a sliding groove 42 bored in the axial direction in the surface plate 4, and its bearing 5 is connected to the feed screw mechanism 1.
It is made movable in the axial direction by engagement with the tip of 6. Then, when attaching the gear to be inspected a to the drive shaft 11.

First, the gear a is placed on the small diameter shaft portion, and then the chuck portion is sent to the small diameter shaft portion side by the feed screw mechanism 16, and the small diameter portions are successively inserted into the inner hole. As a result, the cylindrical outer periphery of the chuck part is pushed outward and pressed against the inner peripheral surface of the center hole of the gear a, the gear a is fixed, and the inner hole of the chuck part is brought into strong contact with the small diameter shaft part. When removing gear a.

The feed screw mechanism 16 is sent in the opposite direction to the above, the chuck part is moved backward, and the gear a is removed. Next, the intermediate shaft system 20 on the right side of the drive shaft system 10 is connected to a sliding pedestal-4 which is loosely engaged with a sliding groove 43 bored parallel to the drive shaft system 10.
4, and on the pedestal 44, the intermediate shaft 21
is rotatably supported by a bearing 23, and a gear to be inspected to be meshed with the gear to be inspected a is located at the protruding end thereof, and the drive shaft system is mounted on a pedestal 44 on the opposite side of the gear. 10, a sliding groove 45 is bored, and the bearing 2 is inserted therein.
A rotating shaft 24 having a chuck portion at its tip is supported by the bearing 25, and is movable in the axial direction by engagement with the tip of the feed screw mechanism 26.

The gear wheel is fixed to the intermediate shaft 21 in the same manner as described above. Further, the pedestal 44 itself has one end in contact with the cam mechanism 22 provided in the sliding groove 43 and the other end in contact with a compression spring 27 provided in the sliding groove 43. Cam mechanism 2
The pedestal 44 and the intermediate shaft thread 20 thereon are reciprocated in the axial direction as the pedestal 44 and the intermediate shaft thread 20 thereon are oscillated by a predetermined angle. The intermediate shaft system 2
In the load shaft system 30 further to the right of 0, the load shaft 31 is connected to the bearing 3.
3, one end of which is rotatably supported by a load device 32.
A gear C to be inspected to be meshed with the gear C to be inspected is located at the other end, and a sliding groove 46 is bored in the axial direction in the surface plate 41 on the opposite side, sandwiching the gear C.

Bearing 35 of rotating shaft 34 which has a chuck part at the tip thereof
The bearing 15 is freely movable in the axial direction by the feed screw mechanism 36, and the gear C disposed on the load shaft 31 is moved by the chuck part in the same manner as described above. It is fixed to the load shaft 31.

Next, the drive shaft 11. Intermediate shaft 21. Reflective pieces 4.5.6 are attached as marks to one place on the circumferential surface of the load shaft 31, and mark detectors 1, 2.3 (but , 2 are fixedly mounted on a pedestal 44 loosely coupled to the surface plate 41). Further, a vibration detector 7 is fixedly installed on the outer peripheral surface of the bearing 23 of the intermediate shaft 21.

Mark detectors 1 to 3 receive reference point signals B, O, and D each time reflective pieces 4 to 6 corresponding to valleys pass through their respective fixed positions.
(Fig. 3), and the vibration detector 7 generates a vibration signal A corresponding to vibrations such as meshing vibrations and bearing vibrations transmitted to the bearing 23.
(Figure 3) is generated.

In the above, the inspection work for dents is performed as follows.

First, the drive shaft 11. Intermediate shaft 21. Position the gears a, b, and c to be inspected on the load shaft 31, and insert the chuck portions of the opposing rotating shafts 14, 24, and 34 into the center holes of the gears from the opposite side. Each drive shaft 11. Intermediate shaft 21. Rotation is transmitted by the load shaft 31.

Subsequently, the drive motor 12 is rotated, and the load device 3 is further rotated.
The generated load of step 2 is set to a predetermined size.

As a result, the gear A, the gear S that meshes with it, and the gear C that meshes with it become in a rotating state. As a result of the gear C receiving a load, the gear C meshes with it.

ζd also rotates while receiving a load. At this time, in the first half of the inspection, the cam mechanism 22 is rotated and stopped at the position shown by the solid line in FIG. 3, and in the second half, it is stopped at the position shown by the two-dot chain line. However, the intermediate shaft 21° gear wheel integral therewith reciprocates, and the meshing position of the entire tooth width of the gear wheel is established with respect to the gears a and c.

During this time, the meshing vibration of gears a, b, and c, and the bearings 13 and 15
．． The vibration detector 7 converts the vibration transmitted to the bearing 23 of the intermediate shaft 21 into an electrical signal A among various generated vibrations such as the vibration of the drive motor 12, the vibration of the cam mechanism 22, etc. At the same time, the mark detectors 1, 2, 3 are connected to the drive shaft 11. Every rotation of the intermediate shaft 21° load shaft 31, the reference point signals B, C, are generated by opposing the reflecting pieces 4, 5.6
D is output.

Then, each signal A, B, 0 . D is electrically processed by the circuit shown in FIG.

In the above explanation, the vibration signal is taken out from the bearing of the intermediate shaft, but it is also possible to use a bearing of another shaft, or a vibration extraction ring in which the inner ring rotates and the outer ring remains stationary for vibration detection. may be provided and the vibration signal may be extracted from it,
Furthermore, a vibration detector may be provided for each axis.

In addition, for attaching and detaching the gear to be inspected to and from the shaft, there are known attachment and detachment means such as center splines and key collet chucks.
If the gear is integrated, the gear mounting shaft itself must be attached to and detached from the drive shaft or the like.

Further, as the reciprocating means for the intermediate shaft system 10, there are a cam mechanism, a reciprocating cylinder mechanism, a screw feeding mechanism, and the like.

Further, although the synchronous addition of the adding section is not described in detail, it is possible to add the dent signal at regular minute intervals in synchronization with a conventionally known reference point signal.

A rotary encoder is provided on one of the axes of the above, and the dent signals are A/D converted by the pulses thereof and added digitally.

It can be either analog or digital.

As described above, the present invention rotates all meshing gear trains of a multi-shaft meshing gear system in mesh with each other.

During this time, the vibration signal is detected and a dent signal is extracted from it, and the dent signal is synchronized with the reference point signal of each axis and processed, and based on the magnitude of the added output, each gear is Since the presence or absence of dents is determined, all gears in the gear train can be inspected simultaneously with high accuracy in one inspection.Since the 2nd determination is performed by adding the dent signals, the 1st determination is automatic. Furthermore, the inspection efficiency is greatly improved.

[Brief explanation of the drawing]

Figure 1 is a flock diagram of the previously proposed dent signal extraction section, Figure 2 is a waveform diagram showing the vibration signal extracted from the vibration detector and the dent signal extracted from it, and Figure 3 is the detection A block diagram of the signal processing section, FIG. 4 is a plan view showing an embodiment of the present invention. 10: Drive shaft system, 20. Intermediate shaft system, 30: Load shaft system. 40: machine base, 50: dent signal extraction section, 60. Addition section. 1 to 3: Mark detector, 4 to 6: Mark, 7: Vibration detector, 11: Drive shaft, 21: Intermediate shaft, 31: Load axis = 1 Figure 1, 2 Figures + 4 Figures, 3 Figures

Claims (1)

[Claims] ■ A drive farm wheel, at least one intermediate gear, and an extractor d
Rotation is transmitted by the J gear, the entire vibration signal from one of the rotations 111 of the valley gear is detected, and the signal component due to the dent is extracted from it. Separately, the reference point signal of each vehicle is detected, the signal component is added in synchronization with each reference point signal, and the presence or absence of a dent on each gear is determined based on the magnitude of the added value. How to inspect marks. 2. A driving gear, at least one intermediate gear, and a driven gear are supported by their respective rotating shafts in a 11i4 state on the machine base, and an imaging detector is attached to the fixed support of any rotating shaft, A gear dent inspection device with marks attached to it and a mark detector set on the rear stand opposite each mark.