JP2017194311A - Gear tooth profile measuring device and tooth profile measuring method - Google Patents

Abstract

An object of the present invention is to provide a tooth profile measuring device and a tooth profile measuring method for a gear that is capable of measuring the tooth profile of a rotating gear while suppressing the influence of dirt on the tooth surface.
A laser rangefinder for measuring a measurement target distance until a laser beam irradiated from an irradiation unit having a fixed irradiation direction hits an outer peripheral surface of a rotating gear, a plurality of times at different timings; The rotation angle meter 22 for measuring the rotation angle of the gear 11 and the coordinates separated from the irradiation unit 16 by the measurement target distance in the irradiation direction on the coordinate system with the rotation center of the gear 11 as the origin for each measurement target distance. And a calculation unit 15 for deriving the shape of the tooth portion 12 of the gear 11 by correcting each coordinate based on the rotation angle of the gear 11 on the coordinate system.
[Selection] Figure 2

Description

The present invention relates to a tooth profile measuring device and a tooth profile measuring method for measuring a tooth profile of a gear.

Gears used in various facilities have broken teeth and rough tooth surfaces as types of deterioration damage. When the tooth part breakage, which is serious deterioration damage, occurs, the equipment can be restored by replacing the gear. However, if the gear is large and the frequency of breakage is low, it is rare to prepare a spare part for replacement.If the gear breaks, the gear must be remanufactured and the equipment downtime is reduced. There is a minimum risk of months.
Therefore, it is important to grasp the state of the tooth portion so that a replacement can be prepared before breaking, especially for a gear that cannot be manufactured in a short period of time.

Conventional methods for detecting the state of teeth include measuring with a caliper, measuring the gap by applying a template, and taking a tooth profile with resin, etc., but these take time and require a long time for the equipment. It was necessary to pause.
Therefore, a method for inspecting the state of the gear without pausing the equipment for a long time is required, and a specific example is described in Patent Document 1. The method described in Patent Literature 1 irradiates a gear with laser light and detects the state of the tooth surface based on the amount distribution of the laser light reflected by the tooth surface of the gear.

JP2013-221845A

However, since the method described in Patent Document 1 detects the state of the tooth surface based on the intensity profile of the reflection of the laser beam, it is easily affected by dirt on the tooth surface, and an accurate tooth depending on the use environment of the gear. There was a problem that the state of the surface could not be detected.
The present invention is made in view of such circumstances, and a gear tooth profile measuring device capable of measuring a tooth profile in a short time without being affected by dirt on the tooth surface of a gear rotating in a state of being attached to equipment. And it aims at providing a tooth profile measuring method.

The tooth profile measuring apparatus according to the first aspect of the present invention is configured to calculate a distance to be measured until a laser beam irradiated from an irradiation unit having a fixed irradiation direction hits an outer peripheral surface of a rotating gear that is still attached to equipment. A laser distance meter that measures a plurality of times at different timings, a rotation angle meter that is attached to the rotation shaft of the gear and measures the rotation angle of the gear, and the rotation center of the gear is the origin for each measurement target distance The coordinates separated from the irradiation unit in the irradiation direction by the distance to be measured are obtained on the coordinate system, the coordinates are corrected based on the rotation angle of the gear on the coordinate system, and the gear teeth A calculation unit for deriving the shape of the unit.

In the tooth profile measuring apparatus according to the first invention, the coordinate system is preferably a polar coordinate system.

In the tooth profile measuring apparatus according to the first aspect of the present invention, the laser distance meter includes, as the irradiation unit, a first irradiation unit that applies laser light to a front surface of the tooth unit in the gear rotation direction, and a gear rotation of the tooth unit. A second irradiation unit that irradiates a laser beam to the rear surface in the direction, and the calculation unit calculates the distance from the measurement target measured based on the laser beam emitted from the first irradiation unit. Deriving the shape of the front surface of the tooth portion in the gear rotation direction, the surface of the tooth portion on the rear side in the gear rotation direction from the measurement target distance measured based on the laser light emitted from the second irradiation unit It is preferable to derive the shape.

According to the gear tooth profile measuring method according to the second aspect of the present invention, the laser beam irradiated from the irradiation section whose irradiation direction is fixed hits the outer peripheral surface of the rotating gear that is still attached to the equipment. On the coordinate system with the rotation center of the gear as the origin for each measurement target distance, Step A for measuring the measurement target distance up to several times at different timings, Step B for measuring the rotation angle of the gear Step C for obtaining coordinates separated from the irradiation unit in the irradiation direction by the distance to be measured, and correcting each coordinate based on the rotation angle of the gear on the coordinate system, And D for deriving the shape of

In the gear tooth profile measuring method according to the second aspect of the invention, the coordinate system is preferably a polar coordinate system.

In the gear tooth profile measuring method according to a second aspect of the invention, the irradiating unit includes a first irradiating unit that applies laser light to a front surface of the tooth part in the gear rotation direction, and a rear side of the tooth part in the gear rotation direction. A second irradiation unit that irradiates the surface with laser light, and from the measurement target distance measured based on the laser light irradiated from the first irradiation unit, It is preferable to derive the shape and derive the shape of the rear surface of the tooth portion in the gear rotation direction from the measurement target distance measured based on the laser light emitted from the second irradiation unit.

According to the gear tooth profile measuring device according to the first invention and the gear tooth profile measuring method according to the second invention, the rotating gear while attached to the equipment is not affected by the contamination of the tooth surface for a short time. Can measure the tooth profile of the gear and shorten the equipment downtime associated with the measurement.

It is explanatory drawing which shows the mode of the distance measurement of the laser distance meter with which the gear tooth profile measuring apparatus which concerns on one embodiment of this invention is provided. It is explanatory drawing of the tooth profile measuring apparatus of the gear. It is explanatory drawing which shows the mode of the distance measurement of the laser distance meter with which the gear tooth profile measuring apparatus which concerns on a modification is provided. It is explanatory drawing of the tooth profile measuring apparatus of the gear. It is explanatory drawing which shows the correction method of a measuring object coordinate. It is explanatory drawing which shows the experimental result which measured the shape of the outer peripheral surface of a gearwheel.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1 and 2, a gear tooth profile measuring device (hereinafter also referred to as “tooth profile measuring device 10”) according to an embodiment of the present invention is a rotation in which a plurality of tooth portions 12 are formed on the outer periphery. Based on the laser distance meter 14 for measuring the measurement target distance until the laser beam irradiated from the irradiation unit 16 with the irradiation direction fixed hits the outer peripheral surface 13 of the inner gear 11, and based on the measured measurement target distance, A calculation unit 15 for deriving the shape of the tooth portion 12 of the gear 11 is provided. Details will be described below.

As shown in FIG. 1, the tooth profile measuring device 10 includes a laser distance meter 14 disposed at a position away from the gear 11. The laser range finder 14 includes an irradiation unit 16 having a fixed irradiation direction, and the irradiation unit 16 has a rotating gear 11 that is still attached to an unillustrated facility (equipment to which the gear 11 is rotatably mounted). Laser light is irradiated toward the outer peripheral surface 13. The laser distance meter 14 receives the laser beam irradiated from the irradiation unit 16 and reflected by the outer peripheral surface 13 of the gear 11, and measures from the irradiation unit 16 to the portion where the laser beam of the outer peripheral surface 13 of the gear 11 hits. Measure the target distance.

As shown in FIG. 2, the outer peripheral surface 13 of the gear 11 includes a bottom surface 24 provided between the tooth portions 12 and a front surface formed on the tooth portion 12 in the gear rotation direction (hereinafter referred to as “gear rotation”). Direction front side surface 17 ”, the gear rotation direction rear surface formed on the tooth portion 12 (hereinafter referred to as“ gear rotation direction rear side surface 18 ”), the gear rotation direction front side surface 17, and the gear rotation direction rear side surface. It consists of a tooth tip surface 25 which is a flat surface formed between 18 (radially outside). Needless to say, the tooth tip surface 25 is not limited to a flat surface.

The laser distance meter 14 is attached to a support member (not shown), and the laser beam emitted from the irradiation unit 16 is rotated by the bottom surface 24 of the rotating gear 11, the gear rotation direction front side surface 17, the tooth tip surface 25 and the gear rotation direction rear side surface. 18 are sequentially arranged. The laser distance meter 14 performs measurement of a measurement target distance by receiving laser light a plurality of times at a predetermined time interval (that is, measures a plurality of times at different timings). For this reason, the measurement target distance measured by the laser distance meter 14 varies depending on the measurement timing.

The time interval at which the laser distance meter 14 measures the measurement target distance is adjusted so that a plurality of measurement target distances can be measured for the gear rotation direction front side surface 17 and the gear rotation direction rear side surface 18 of each tooth portion 12. . In the present embodiment, 20 or more measurement target distances are measured for the front side surface 17 in the gear rotation direction and the rear side surface 18 in the gear rotation direction of each tooth portion 12.

As shown in FIG. 2, the laser distance meter 14 is connected to the calculation unit 15 via the amplifier 19, and the measurement target distance measured by the laser distance meter 14 is sent to the calculation unit 15. The computing unit 15 can be configured by a computer (electronic computer) that includes a hardware device and software.
A rotation angle meter 22 that measures the rotation angle of the gear 11 is connected to the calculation unit 15 via the amplifier 20, and the rotation angle meter 22 transmits a measured value of the rotation angle of the gear 11 to the calculation unit 15. The rotation angle meter 22 is attached to a rotation shaft 23 (see FIG. 1) of the gear 11.

The calculation unit 15 includes a coordinate system (hereinafter also referred to as “basic coordinate system”) having the center of the rotation shaft 23 of the gear 11 (the rotation center of the gear 11) as the origin O (see FIG. 5), and the laser distance to the gear 11. The relative position of the total 14 (in this embodiment, the irradiation unit 16) and the irradiation direction of the laser beam of the irradiation unit 16 are registered in advance.
The calculation unit 15 is configured to coordinate the measurement target distance with respect to the value of the measurement target distance obtained from the laser distance meter 14 by a measurement target distance in the irradiation direction of the laser light from the irradiation unit 16 on the basic coordinate system (hereinafter, “ Also called “measurement coordinates”. In the present embodiment, the basic coordinate system is a polar coordinate system defined by a radius vector and a declination angle, but is not limited thereto, and may be, for example, an orthogonal coordinate system.

And the calculating part 15 correct | amends the measuring object coordinate corresponding to each measuring object distance measured at different timing on a basic coordinate system based on the measured rotation angle of the gearwheel 11, and each tooth part 12 is correct | amended. Deriving the shape.
Here, wear of the tooth portion 12 occurs on the front side surface 17 in the gear rotation direction and the rear side surface 18 in the gear rotation direction. Therefore, it is important to accurately detect the contours (shapes) of the gear rotation direction front side surface 17 and the gear rotation direction rear side surface 18 at the tooth portion 12.

Further, in the present embodiment, the shape of the tooth portion 12 is derived by using one laser distance meter 14, but in order to detect the shape of each tooth portion 12 with high accuracy, FIG. 3 and FIG. As shown, it is preferable to use two laser beams with different irradiation directions.
Hereinafter, with reference to FIGS. 3 and 4, a tooth profile measuring device 30 which is a modification of the tooth profile measuring device 10 will be described. In addition, about the structure similar to the tooth profile measuring apparatus 10, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

The laser distance meter 31 provided in the tooth profile measuring device 30 includes irradiation units 32 and 33 (first and second irradiation units) having different laser light irradiation directions. The irradiation unit 32 can apply laser light to the entire front side surface 17 and the entire tooth tip surface 25 in the gear rotation direction, and is arranged so that the laser beam does not hit the rear side surface 18 in the gear rotation direction. Laser light can be applied to the entire rear surface 18 in the direction and the entire tooth tip surface 25, and the laser light can be applied to the front surface 17 in the gear rotation direction.

The irradiation units 32 and 33 are connected to the calculation unit 36 via amplifiers 34 and 35, respectively.
The calculation unit 36 derives the shape of the entire front side surface 17 in the gear rotation direction of each tooth portion 12 from the measurement target distance measured based on the laser light emitted from the irradiation unit 32 and is irradiated from the irradiation unit 33. From the measurement target distance measured based on the laser beam, the shape of the entire rear side surface 18 in the gear rotation direction of each tooth portion 12 is derived. Due to the arrangement of the irradiation units 32 and 33 described above, the irradiation units 32 and 33 can irradiate the laser beam to the front side surface 17 in the gear rotation direction and the rear side surface 18 in the gear rotation direction at angles close to perpendicular, respectively. The tooth profile measuring device 30 can derive the shapes of the gear rotation direction front side surface 17 and the gear rotation direction rear side surface 18 with higher accuracy than the tooth profile measurement device 10.

Hereinafter, the tooth profile measuring method of the gear using the tooth profile measuring apparatus 10 will be described.
The tooth profile measurement method of the gear is to measure the distance to be measured until the laser beam irradiated from the irradiation unit 16 with the irradiation direction fixed on the outer peripheral surface 13 of the rotating gear 11 attached to the equipment hits the outer peripheral surface 13. The process A for measuring multiple times at different timings, the process B for measuring the rotation angle of the gear 11, and the irradiation direction of the laser light from the irradiation unit 16 to the irradiation unit 16 on the basic coordinate system for each measurement target distance. A step C for obtaining measurement target coordinates separated by a measurement target distance, and a step D for deriving the shape of the tooth portion 12 of the gear 11 by correcting each measurement target coordinate based on the rotation angle of the gear 11 on the basic coordinate system. And have.

In step A, the laser distance meter 14 irradiates the laser beam and measures the measurement target distance to the outer peripheral surface 13 of the rotating gear 11 at a plurality of times at different timings. The time interval during which the laser distance meter 14 irradiates the laser beam to measure the distance is more accurate for the shape of the tooth portion 12, particularly the shape of the front side surface 17 in the gear rotation direction and the rear side surface 18 in the gear rotation direction that is more markedly worn. It can be measured. In that sense, it is preferable to measure at least 20 measurement target distances for each tooth portion 12 with respect to the front side surface 17 in the gear rotation direction and the rear side surface 18 in the gear rotation direction.

In step B, the rotation angle meter 22 attached to the rotation shaft 23 of the gear 11 measures the rotation angle of the gear 11. The rotation angle meter may always measure the rotation angle of the gear 11 or may measure the rotation angle in accordance with the timing at which the laser distance meter 14 measures the measurement target distance by a command signal from the calculation unit 15. Good.
In step C, the calculation unit 15 derives measurement target coordinates on the basic coordinate system for each measurement target distance measured in step A.

In step D, the calculation unit 15 corrects each measurement target coordinate on the basic coordinate system based on the rotation angle of the gear 11 at the timing when the measurement target distance that is the basis for obtaining each measurement target coordinate is measured, The shape of each tooth part 12 is derived.
Specifically, as shown in FIG. 5, in the polar coordinate system starting from the positive direction of the x-axis, for example, the coordinates calculated from the measurement target distance measured n-th is P1 (r1, θ1), The coordinate calculated from the n + 1 measurement object distance is P2 (r2, θ2), and the gear 11 is rotated at an angle dθ from the measurement of the n + 1 measurement object distance to the measurement of the n + 1 measurement object distance. A circle whose center is the origin O on the basic coordinate system and whose radius is the distance r2 between the origin O and P2 (r2, θ2) is a virtual circle R, and the tooth portion 12 is based on P1 (r1, θ1). P2 (r2, θ2) is corrected to P2 ′ (r2, θ2 + dθ) obtained by moving dθ along the outer circumference of the virtual circle R in the direction opposite to the rotation direction of the gear 11. Then, the measurement target coordinates calculated from the n + k-th measurement target distance are k × dθ in the direction opposite to the rotation direction of the gear 11 along the outer circumference of the virtual circle whose radius is the radius of the measurement target coordinates. It is corrected to the moved coordinates. The shape of the tooth portion 12 is derived by connecting coordinates obtained by correcting the measurement target coordinates. Although θ1 and θ2 indicate different angles, there may be a case where θ1 = θ2, and FIG. 5 shows a case where θ1 = θ2.

Then, the calculation unit 15 compares the derived shape of each tooth portion 12 with the shape of each tooth portion 12 measured with respect to the gear 11 when not in use and the design shape (tooth profile reference curve, etc.) of the tooth portion 12. The difference is obtained as the wear amount of the tooth portion 12. In the present embodiment, the wear of the gear rotation direction front side surface 17 and the gear rotation direction rear side surface 18 has a greater influence on the breakage of the tooth portion 12 than the wear of other regions. The possibility of the tooth portion 12 being damaged is evaluated by focusing on the amount of wear on the front side surface 17 in the rotation direction and the rear side surface 18 in the gear rotation direction.

In the tooth profile measuring method of the gear 11 by the tooth profile measuring device 30, the shape of the front side surface 17 in the gear rotation direction of the tooth portion 12 is derived from the measurement target distance measured based on the laser beam irradiated from the irradiation unit 32. The shape of the rear side surface 18 in the gear rotation direction of the tooth portion 12 is derived from the measurement target distance measured based on the laser light emitted from the irradiation unit 33.

Next, an experiment conducted for confirming the effect of the present invention will be described.
In the experiment, two laser distance meters capable of irradiating laser light on the front side and the rear side in the gear rotation direction of the rotating gear are used, respectively, one front side in the gear rotation direction and one rear side in the gear rotation direction. The measurement time interval was adjusted so that 41 measurement target distances were measured for each side surface. The gear had 164 teeth.
A part of the detected contour of the outer peripheral surface of the gear is shown in FIG. In FIG. 6, the coordinates of the measurement target coordinates obtained from the respective measurement target distances are connected by a line to represent the shape of the corresponding region. In FIG. 6, the interdental (98-97) shows the shape of the region from the 97th tooth to the 98th tooth, and the interdental (102-101) and interdental (121-120) are also The shape of the region corresponding to the corresponding number is shown, the solid line is the detection result for the gear with wear, and the phantom line is the detection result for the gear without wear. Thus, according to the present invention, it is possible to grasp the wear state of the tooth portion.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and all changes in conditions and the like that do not depart from the gist are within the scope of the present invention.

10: Tooth profile measuring device, 11: Gear, 12: Tooth part, 13: Peripheral surface, 14: Laser distance meter, 15: Calculation part, 16: Irradiation part, 17: Front side in gear rotation direction, 18: After gear rotation direction Side surface, 19, 20: amplifier, 22: rotation angle meter, 23: rotation axis, 24: bottom surface, 25: tooth tip surface, 30: tooth profile measuring device, 31: laser distance meter, 32, 33: irradiation unit, 34, 35: Amplifier, 36: Calculation unit

Claims (6)

A laser rangefinder that measures the distance to be measured multiple times at different timings until the laser beam irradiated from the irradiation unit that fixed the irradiation direction hits the outer peripheral surface of the rotating gear that remains attached to the equipment,
A rotation angle meter attached to the rotation shaft of the gear and measuring the rotation angle of the gear;
For each of the measurement target distances, a coordinate that is separated from the irradiation unit in the irradiation direction by the measurement target distance is obtained on a coordinate system with the rotation center of the gear as an origin, and each coordinate is calculated on the coordinate system. An apparatus for measuring a tooth profile of a gear, comprising: an arithmetic unit that derives a shape of a tooth portion of the gear by correcting based on the rotation angle of the gear. The gear tooth profile measuring device according to claim 1, wherein the coordinate system is a polar coordinate system. The laser distance meter applies, as the irradiation unit, a first irradiation unit that applies laser light to a front surface of the tooth portion in the gear rotation direction, and a laser beam applied to a rear surface of the tooth portion in the gear rotation direction. 2 irradiation parts,
The calculation unit derives the shape of the front surface of the tooth portion in the gear rotation direction from the measurement target distance measured based on the laser beam emitted from the first irradiation unit, and the second irradiation The tooth profile of the gear according to claim 1 or 2, wherein a shape of a surface on the rear side in the gear rotation direction of the tooth portion is derived from the measurement target distance measured based on the laser beam irradiated from the portion. Measuring device. Step A for measuring the measurement target distance until the laser beam irradiated from the irradiation unit whose irradiation direction is fixed to the outer peripheral surface of the rotating gear that is still attached to the equipment hits the outer peripheral surface at a plurality of times at different timings. ,
Measuring the rotation angle of the gear B;
For each measurement target distance, obtaining a coordinate C that is separated from the irradiation unit in the irradiation direction by the measurement target distance on a coordinate system having the rotation center of the gear as an origin; and
And a step D for deriving a shape of a tooth portion of the gear by correcting each coordinate based on the rotation angle of the gear on the coordinate system. The gear tooth profile measuring method according to claim 4, wherein the coordinate system is a polar coordinate system. The irradiation unit includes: a first irradiation unit that applies laser light to a surface of the tooth portion on the front side in the gear rotation direction; and a second irradiation unit that applies laser light to a surface on the rear side in the gear rotation direction of the tooth portion. Become
From the measurement target distance measured based on the laser light emitted from the first irradiation unit, the shape of the front surface of the tooth portion in the gear rotation direction is derived and irradiated from the second irradiation unit. The gear tooth profile measuring method according to claim 4 or 5, wherein the shape of the surface of the tooth portion on the rear side in the gear rotation direction is derived from the measurement target distance measured based on a laser beam.

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