JPH0333609A - Measuring method of accuracy of bevel gear and apparatus thereof - Google Patents

Abstract

PURPOSE:To measure the accuracy with the phase error separated from the total error by making a member to which is fixed each positioning pin an arc-shaped body movable along the same circumference. CONSTITUTION:While a positioning pin 20 among the three pins is fixed, a master gear is mounted on the three pins 20, so that the master gear is supported at the three points. The other pins 20 are moved to a reference position of the master gear, where they are positioned and fixed. Then, a value corresponding to the fixing position of the two positioning pins 20 at the reference position is set as a reference value for a measuring part. Thereafter, a bevel gear 24 is mounted on the three pins 20, so that the bevel gear is supported at the three points while the one pin is fixed and the other two pins 20 are in the movable state. When the bevel gear 24 becomes stable by moving the two pins 20, the difference between the measuring value of the measuring part and the reference value is rendered the displacement amount.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for measuring the accuracy of a bevel gear, which are preferably used when measuring the accuracy of a bevel gear easily and with high precision.

[Prior Art] Due to the technical difficulties involved in measuring the accuracy of bevel gears, the actual situation is that no desirable accuracy evaluation method has been established.

Currently, for example, there is a known technology for measuring the accuracy of bevel gears by combining a three-dimensional measuring device, which is considered a universal measuring device, and a computer, but devices made by combining a measuring device and a computer are expensive. In addition, there are problems in that highly sophisticated techniques are required during measurement and the measurement time is long.

Additionally, there are known devices that measure the runout of the tooth structure using the outer or inner diameter surface of a boss formed on the gear as a reference surface (Japanese Patent Publication No. 60-25721, Japanese Patent Publication No. 60-25721, Japanese Patent Publication No. 60-25721,
55761], if there is a misalignment between the reference surface and the tooth surface, there is a risk that the misalignment has already occurred when machining the reference surface, which may cause problems with the reliability of the measurement results. be.

Moreover, such a problem similarly exists in the devices described in Japanese Utility Model Application Publication No. 63-62705, Japanese Utility Model Publication No. 63-199047, and the like.

Therefore, by using a jig with three-point support, a steel ball, etc. is brought into contact with both tooth surfaces of the tooth groove on the same circumference with the master gear as a reference, and the amount of the steel ball going in and out (the amount of the steel ball going in and out of the tooth groove). Accuracy measurements are being conducted to determine that runout (runout) is due to misalignment and variation in tooth thickness (JIS B1704;
(See bevel gear accuracy).

In the accuracy inspection, considering the properties of bevel gears, it is possible to determine which deviation or error is caused by tooth thickness error, phase deviation, distance from the center, or tooth profile error. First, the only way to judge it is as a total error that includes all of these deviations or errors, so although it is a simple accuracy test, it is difficult to say that it is an appropriate accuracy evaluation.

Therefore, in the inspection, the presence or absence of errors is judged based on the total error, which makes analysis after the inspection difficult. Therefore, it is necessary to make a final determination by performing a meshing inspection, or by adjusting shims during assembly. The inspection is being carried out.

[Problem to be solved by the invention] However, when the gear is a so-called gear cutter, accuracy is guaranteed by the processing method using a gear cutter made by Gleason, but a bevel gear is not formed by forging or the like. In this case, it is necessary to manufacture a mold using an electrode with gears cut by Gleason, and to further plastically process the bevel gear forged using that mold, so the above deviations or errors may accumulate due to springback and other factors. There is a problem with being exposed.

Moreover, even when manufacturing molds, the above-mentioned deviations or errors that are the cause of correction are unclear, so it is difficult to judge which error should be corrected, and as a result, it is difficult to make appropriate corrections. I had a problem.

An object of the present invention is to, when a bevel gear is placed on three positioning pins (support pins) each having a steel ball at its tip and its accuracy is measured, the members to which the positioning pins are each fixed are To provide a method and device for measuring accuracy of a bevel gear, which makes it possible to measure accuracy by separating a phase error from a total error by forming arcuate bodies each movable along the same circumference. It is in.

[Means for Solving the Problems] In order to achieve the above-mentioned object, a method for measuring accuracy of a bevel gear according to the present invention includes: a bevel gear to be measured is mounted so that it can be supported at three points; In a method for measuring the accuracy of a bevel gear, in which accuracy is measured by measuring the amount of displacement of three positioning pins movable along the circumference from a reference position by a measurement unit, With any one of the locating pins fixed, the master gear is placed on the three locating pins and supported at three points, so that the remaining two locating pins are connected to the master gear. a first step of being moved to a reference position corresponding to, positioning and fixing;
After the value corresponding to the fixed position of the two positioning pins positioned and fixed at the reference position in the first step is set as the reference value of the measurement unit, the one positioning pin is fixed, and With the two positioning pins movable, the bevel gear is placed on the three positioning pins and supported at three points, and the movement of the two positioning pins stabilizes the bevel gear. and a second step in which the difference between the measured value at the measuring unit and the reference value is determined as the displacement amount when the position is changed.

Furthermore, the bevel gear accuracy measuring device according to the present invention includes three positioning pins that are arranged at equal intervals on the same circumference, and on which the bevel gear to be measured is placed and supported at three points; The positioning pins are each fixed, and three arcuate bodies are arranged along the same circumference with predetermined gaps between them, and three arcuate bodies are formed along the circumference on which the arcuate bodies are arranged. a rotating member rotatably supported around the axis of the bevel gear; and a fixed base rotatably supporting the rotating member. Features.

[Function] In the bevel gear accuracy measuring method according to the present invention, the first
In the process, the two positioning pins are positioned at the reference position.
The value corresponding to the fixed position is taken as the reference value for measurement, and 2
When the bevel gear placed on the three positioning pins becomes stable due to the movement of the book's positioning pins, the difference between the measured value at the measuring section and the reference value is the difference between the two positioning pins and the reference value. This is the amount of displacement from the reference position.

Furthermore, in the bevel gear accuracy measuring device according to the present invention, 3
A book positioning pin is fixed to each of the three arcuate bodies, and each of the arcuate bodies is housed in a groove provided in the rotating member and is movable within the groove. It is rotatably supported around the axis of the bevel gear by a fixed base.

0 [Example] Next, a preferred example of a bevel gear accuracy measuring method and apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 1, a bevel gear accuracy measuring device 10 includes a cylindrical bed 14 fixed to the side surface in the thickness direction of a cylindrical bed fixing base 12, and a shaft formed on the side surface in the axial direction of the bed 14. A rotating member 16 is supported in the hole 14a and is rotatable around the axis of the bed 14, and a rotating member 16 is housed in a groove 16a provided along the circumferential direction of the rotating member 16 and is movable within the groove 16a. three split rings (arc-shaped bodies) 18, three positioning pins 20 whose bases are fixed to each split ring 18 and have steel balls 22 at their protruding ends, and a bed fixing machine base. It has a dial gauge 26 provided at 12.

In this embodiment, the fixing bolt 30 is screwed into a screw hole provided along the radial direction of the rotating member 16 and facing the split ring 18 at the bottom of the tank. Since the tip of the bolt 30 is long enough to come into contact with the first split link 18, the split ring 18 can be fixed at a desired position (inside the groove 16a) by the fixing bolt 30.

Further, the bed fixing machine base 12 and the bed 14 are integrated to form a fixed base, and furthermore, a through hole 16b is provided at the radially central position of the rotating member 16 along its axial direction.

A cylindrical convex portion 28a formed on the bevel gear presser 28 for pressing the bevel gear 24 when the bevel gear 24 is supported at three points by the positioning pins 20 is inserted into the through hole 16b. The threaded portion 28b provided on the protruding end is inserted into the threaded hole 1 provided in the bed 14.
4b, the bevel gear 24 is positioned at the bottom of the tank so that it comes into contact with the positioning pin 20 with an appropriate biasing force.

Note that the bevel gear 24 placed on the positioning pin 20
As a means for pressing, it is preferable to place a weight or the like on the bevel gear 24, and it is also preferable to press with a cylinder adjusted to an appropriate air pressure.

In addition, in the dial gauge 26, a mounting piece 26a provided on the back surface of the casing is rotatably attached to a mounting piece 12a provided on the bed fixing machine base 12. spindle 2
6b is rotatable in both directions, away from and in contact with the bevel gear 24.

Here, as can be understood from FIG. 2, each divided ring 18 is formed by dividing a donut-shaped member into three parts by, for example, wire-cut electric discharge, and between adjacent divided rings 18 and 18. The maximum value of the gap T is 0.2 [:mm
), the gap T becomes the allowable displacement amount by which each split ring 18 can be displaced.

As explained above, in this embodiment, the bevel gear 24 has three
The split ring 18 is supported at three points by two positioning pins 20, and each positioning pin 20 is fixed to the groove part 16.
As a result, the steel ball 22 provided at the protruding end of the positioning pin 20 can easily move in the tooth groove of the bevel gear 24. It abuts inside.

Therefore, measurements can be carried out efficiently, measurements can be made even with unprocessed finely forged teeth, and measurement errors (phase errors) due to pitch errors of the bevel gear 24 can be avoided.

In addition, the amount of displacement of at least two of the three positioning pins 20 in two directions within a rectangular coordinate system on a horizontal plane (a coordinate system formed by mutually orthogonal X-axis and Y-axis within the horizontal plane) It is also preferable to provide a measuring section such as a dial gauge capable of measuring each of the above to improve the measurement accuracy at the bottom of the tank.

Next, a method for measuring accuracy of a bevel gear according to the present invention will be explained.

First, any one of the three positioning pins 20 is fixed. That is, 4 split rings 1 to which the base of the positioning pin 20 is fixed;
B is fixed with fixing bolts 30.

The remaining two positioning pins 20 are made movable along the groove 16a, and a master gear (not shown) is placed on the three positioning pins 20.
The book is supported at three points by positioning pins 20.

At this time, the remaining two positioning pins 20 are moved to the reference position corresponding to the master gear, so the fixing bolt 3
By tightening 0, the remaining two positioning pins 20
are positioned and fixed at their respective reference positions.

In this state, the protruding end of the spindle 26b of the dial gauge 26 is brought into contact with the steel ball 22 of the initially fixed positioning pin 20, and the reading of the dial gauge 26 in this state is set as a value of 0 (reference value).

After the master gear is removed from the positioning pin 20, the bevel gear 24 to be measured is placed on the positioning pin 20 and supported at three points.

At this time, the first positioning pin 20 is left fixed, and the remaining two positioning pins 20 are left movable along the groove 16a.

Therefore, when the bevel gear 24 is placed on the three positioning pins 20 and pressed by the bevel gear presser 28,
The positioning pin 20 is moved by a distance corresponding to the pitch error of the teeth cut into the bevel gear 24.

Therefore, the spindle 2 is attached to the moved positioning pin 20.
Since the reading (measured value) of the dial gauge 26 when the dial gauge 6b is brought into contact is the difference between the reference value and the measured value, the difference becomes the amount of displacement of the positioning pin 20.

In addition, when calculating the amount of displacement of the positioning pin 20, as understood from FIG. 3, in the X-Y coordinate system which is an orthogonal coordinate system in the horizontal plane, The distance between the position of the 6 positioning pins 20 (displacement position) indicated by the dotted line in the figure is determined from the position (reference position).

Therefore, the reading ΔX of the dial gauge 26 in the X-axis direction is determined, and the reading ΔY of the dial gauge 26 in the Y-axis direction is determined, and the displacement Z of the positioning pin 20 is determined from the following equation (1) from these two values.

Furthermore, when the displacement Z is determined, the phase error θ of the bevel gear 24 with respect to the master gear can be determined from the equation (2) below (
See Figure 5.

Note that the phase error θ is the phase error of the bevel gear 24 with respect to the master gear measured between the distance φd in FIG. It becomes possible to evaluate the accuracy of the bevel gear 24 in which the phase error is separated.

As explained above, in this embodiment, since the phase error θ is calculated from the deviation amounts ΔX and ΔY of the positioning pin 20, by measuring the entrance and exit of the teeth of the bevel gear 24, the Since it is possible to evaluate the accuracy separately from the phase error θ, it becomes easy to analyze the accuracy of the bevel gear 24, and the modification work of the bevel gear 24 can be performed appropriately.

In addition, when the inner periphery of the tooth surface of the bevel gear 24 is supported at three points by the positioning pin 20, the position near the inner periphery of the tooth surface is
Point support makes it possible to prevent the bevel gear 24 from tilting with respect to the horizontal plane.

In that case, the position near the inner periphery of the tooth surface is a range of approximately the diameter X of the steel ball 22 from the inner periphery 24a of the tooth surface of the bevel gear 24 to the outer periphery 24b of the tooth surface. The steel ball 22 preferably conforms to the JIS standard.

In addition, in this embodiment, first, the fixing bolt 30
Although one of the three positioning pins 20 is fixed, as can be understood from FIGS. 7 and 8, one of the three positioning pins 20 is fixed. It is also suitable that the split ring 18 to which the book positioning pin 20 is fixed is fixed in advance with two fixing pins 21, and only the remaining two positioning pins 20 (split ring 18) are movable. It is. In this case, the dial gauge 26 and its pre-fixed positioning pin 2
By making the positional relationship with 0 accurate, the accuracy of the bevel gear 24 can be measured easily and with high precision in the same way as in the embodiment described above.

[Effects of the Invention] 9 As understood from the above explanation, the method for measuring accuracy of a bevel gear according to the present invention includes measurement corresponding to the fixed positions of the two positioning pins positioned and fixed in the first step. The value of the part is taken as the reference value for measurement, and the value measured at the measurement part when the bevel gear placed on the three positioning pins becomes stable by moving these two positioning pins. The difference from the reference value is taken as the amount of displacement of the two positioning pins from the reference position.

Then, since the phase error of the bevel gear with respect to the master gear is measured from the amount of displacement, it is possible to evaluate the accuracy in which the phase error is separated by measuring the entrance and exit of the teeth of the bevel gear.

As a result, accuracy analysis becomes easy, and the bevel gear modification work can be performed appropriately based on the accuracy analysis.

Furthermore, in the bevel gear accuracy measuring device according to the present invention, three positioning pins are each fixed to three arcuate bodies, and each arcuate body is housed in a groove provided in a rotating member. , is movable within the groove, and the rotating member is supported by a fixed base so as to be rotatable around the axis of the bevel gear.

As a result, measurement errors due to pitch errors of the bevel gear can be avoided simply by placing the bevel gear on the positioning pin, making it possible to easily and accurately measure accuracy.

[Brief explanation of drawings]

Fig. 1 is a configuration explanatory diagram of a preferred embodiment of the bevel gear accuracy measuring device according to the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a bevel gear accuracy measurement according to the present invention. An explanatory diagram showing a preferred embodiment of the method. Fig. 4 is an explanatory diagram showing the correlation between the phase error of the bevel gear with respect to the master gear and the amount of deviation of the positioning pin. An explanatory diagram showing the method for determining the accuracy. 1. Figure 6 is an explanatory diagram showing the contact position between the tooth surface of the bevel gear and the steel ball of the positioning pin. Figure 7 is the main part of a bevel gear accuracy measuring device in another embodiment. FIG. 8 is a sectional view taken along the line ■-■ in FIG. 7. 10... Device 12... Bed fixing machine stand 14... Bed 16... Rotating member 1
8... Divided ring (arc shaped body) 20... Positioning pin 21... Fixed pin 22
:...Steel ball 24...Bevel gear 26...Dial gauge 2 3

Claims (6)

[Claims] (1) The bevel gear to be measured is mounted so that it can be supported at three points, and the amount of displacement from the reference position of the three positioning pins that are movable along the same circumference is measured. In a bevel gear accuracy measurement method in which accuracy is measured by measuring the accuracy of a bevel gear, with one of the three positioning pins fixed, the master gear performs positioning of the three positioning pins. A first step in which the remaining two positioning pins are moved to a reference position corresponding to the master gear and positioned and fixed by being placed on the pin and supported at three points;
After the value corresponding to the fixed position of the two positioning pins positioned and fixed at the reference position in the first step is set as the reference value of the measurement unit, the one positioning pin is fixed, and With the two positioning pins movable, the bevel gear is placed on the three positioning pins and supported at three points, and the movement of the two positioning pins stabilizes the bevel gear. A method for measuring accuracy of a bevel gear, comprising: a second step in which a difference between a measured value at the measuring unit and the reference value is determined as the amount of displacement when the bevel gear assumes a certain posture. (2) The bevel gears to be measured are mounted and supported at three points, which are arranged at equal intervals on the same circumference.
a positioning pin for a book; three arcuate bodies to which the positioning pins are each fixed and arranged at predetermined intervals along the same circumference; and a circumference on which the arcuate bodies are arranged. a rotary member that is provided with a groove formed along the curve in which the arc-shaped body is movably housed, and that is rotatably supported around the axis of the bevel gear; and a fixed base that rotatably supports the rotary member. A bevel gear accuracy measuring device characterized by having the following. (3) The method for measuring accuracy of a bevel gear according to claim 1, wherein a position near an inner circumferential portion of a tooth surface of the bevel gear is supported at three points by the positioning pin. (4) The bevel gear accuracy measuring device according to claim 2, further comprising a fixing bolt for fixing the arcuate body at a desired position. (5) In the bevel gear accuracy measuring device according to claim 2 or 4, of the three positioning pins, two positioning pins that move with the movement of the arc-shaped body are displaced within a rectangular coordinate system on a horizontal plane. An accuracy measuring device for a bevel gear, comprising: a measuring section for measuring the amount of displacement. (6) In the bevel gear accuracy measuring device according to claim 2, 4, or 5, one of the three positioning pins is fixed to the rotating member in advance, and the remaining two positioning pins are fixed to the rotating member in advance. The bevel gear accuracy measuring device is characterized in that it is movable as the arcuate body is moved.