JP4212387B2 - Bead tilt angle measuring instrument - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a measuring instrument for measuring an inclination angle of a bead seat portion of a rim constituting an automobile wheel.
[0002]
[Prior art]
As shown in FIG. 6, the rim 1 constituting the automobile wheel supports a sidewall portion (not shown) of the tire, and an inner end rim flange portion 4 a that becomes the vehicle body side when mounted on the automobile. An inner bead seat portion 5a that is coupled to the inner end rim flange portion 4a is formed. Further, an inner hump portion 9a is coupled to the inner bead sheet portion 5a, and a ledge portion 7, an inner well portion 3a, and a drop portion 2 are further formed in this order. Moreover, the outer well part 3b is coupled to the drop part 2, and the outer hump part 9b and the outer bead sheet part 5b are further coupled in order. An outer end rim flange portion 4b is coupled to the outer bead seat portion 5b.
[0003]
By the way, it is well known that the inner and outer bead seat portions 5a and 5b are inclined downward by about 5 ° toward the rim center line m. At the time of manufacture, in order to prevent air leakage at the time of tire mounting, whether or not the inclination angle of the bead seat portions 5a and 5b (hereinafter referred to as the bead inclination angle θ) is within an appropriate angle range. An inspection process for determining is provided.
[0004]
Here, in the inspection step, a configuration using a so-called plate gauge has been proposed as means for determining the suitability of the bead inclination angle θ. Here, as shown in FIG. 7, the general plate gauge is formed between the outer edge of the measurement object U and the plate gauge G with a predetermined outer edge portion along the outer edge of the measurement object U. The presence / absence of a gap is determined to determine the suitability of the shape of the measurement object U (see Non-Patent Document 1, for example).
[0005]
As specific means for determining the suitability of the bead inclination angle θ, as shown in FIG. 8, the board gauge G1 (see FIG. 8A) for inspecting the maximum appropriate inclination angle and the minimum appropriate inclination angle are inspected. A plate gauge G2 (see FIG. 8B) is used. First, as shown in FIG. 8A, the plate gauge G1 is brought into contact with a curved portion in which the inner bead seat portion 5a and the inner end rim flange portion 4a are coupled. Then, the gap generated between the plate gauge G1 and the inner bead sheet portion 5a is visually observed. Similarly, as shown in FIG. 8B, the plate gauge G2 is brought into contact. Then, the gap generated between the plate gauge G2 and the inner bead sheet portion 5a is visually observed. Then, it is determined whether or not the bead inclination angle θ is within an appropriate angle range from the contact state in each case. The means using such a plate gauge is simple and widely used at the manufacturing site.
[0006]
As another means, a configuration is proposed in which the shape of the bead sheet portion is measured by using a three-dimensional measuring device to determine the drawing. In this configuration, the bead inclination angle θ is measured with a minimum reading value of about 0.17 °, for example, and high-precision measurement with few errors is possible.
[Non-Patent Document 1]
2001−The Tire And Rim Association, Inc.-2001 8-59
[0007]
[Problems to be solved by the invention]
However, in the configuration using the above-mentioned plate gauge, the measurer holds the plate gauge and visually checks the slight gap to determine whether it is appropriate. Measurement accuracy is poor due to individual differences in visual judgment. Therefore, there is a problem that it is difficult to ensure reproducibility and repeatability. Further, since the bead inclination angle θ is not represented by a specific numerical value, there is a problem that it is difficult to feed back the inspection result to other equipment such as a mold.
[0008]
On the other hand, the configuration using a three-dimensional measuring instrument requires a great number of man-hours for shape measurement and drawing, and has a problem that production efficiency is remarkably reduced.
[0009]
Therefore, an object of the present invention is to solve the problems of the conventional configuration and to provide a simple and highly accurate bead inclination angle measuring device.
[0010]
[Means for Solving the Problems]
The present invention relates to a base, a rim flange portion on one side formed on a rim to be measured, which protrudes downward from the base, and a reference portion that abuts a bead seat portion that is coupled to the rim flange portion. The other rim flange portion formed on the rim and formed on the rim, the support portion contacting the bead seat portion coupled to the rim flange portion, and the reference portion and the support portion, respectively. A lower end is displaced along the vertical direction, and at a required position, a movable measuring unit that contacts a bead sheet unit that abuts the reference unit, with respect to an imaginary line that connects the lower end of the reference unit and the lower end of the support unit A bead inclination angle measuring device that measures an inclination angle of a bead sheet part with respect to the imaginary line from a vertical distance of a lower end of a movable measurement part (claim 1). Here, the inclination angle (bead inclination angle θ) of the bead seat portion refers to the inclination angle of the bead seat portion with respect to the wheel axis direction of the rim to be measured.
[0011]
In such a configuration, (1) the shortest distance between the lower end of the reference portion and the vertical line related to the movable measurement unit (hereinafter referred to as measurement unit separation distance D), and (2) the lower end of the movable measurement unit relative to the virtual line The vertical distance x and {circle around (3)} bead inclination angle θ satisfy the following relationship (for example, see FIG. 4).
tan θ = x / D
Here, the measurement unit separation distance D is a value that can be known in advance at the manufacturing stage of the measuring device, and the vertical distance x is a value that is measured by the measurer at any time. Therefore, the bead inclination angle θ is calculated from the above equation. It can be obtained. Therefore, it is possible to determine whether the angle is within the required appropriate angle range by placing the bead inclination angle measuring device according to the present invention on the rim and knowing the bead inclination angle θ. Become. In addition, since the bead inclination angle measuring device has a simple configuration and a size that is convenient for carrying around, the bead inclination angle measuring device is convenient, for example, at the manufacturing site.
[0012]
Further, as described above, the reference portion is in contact with the rim flange portion and the bead seat portion on one side, and the support portion is in contact with the rim flange portion and bead seat portion on the other side. Thus, when the bead inclination angle measuring device is placed on the rim, the bead inclination angle measuring device is not displaced in the wheel axis direction of the rim. Therefore, measurement can be performed at a fixed position, and the imaginary line is not unduly displaced during measurement with respect to the wheel axis direction, so that the measurement accuracy of the bead inclination angle θ is improved.
[0013]
Further, the support portion is constituted by a movable support member that is separate from the base member, and the movable support member is disposed on the base member through at least a compression spring, and the movable support member is attached to the rim flange portion and the bead sheet. A configuration is proposed in which the part is elastically contacted with the part (claim 2).
[0014]
That is, the maximum separation distance between the outer edge of the reference portion and the outer edge of the support is determined to be slightly larger than the rim width of the rim to be measured. Then, the bead inclination measuring device is placed on the rim while pushing the movable support against the base side against the elastic force of the compression spring. In this state, the movable support is placed on the rim flange portion and the bead seat. Energize the part.
[0015]
By adopting such a configuration, there is an error in the rim width between a plurality of rims to be measured, and even when the rim width changes every time a different rim is measured, the compression spring according to the present invention. As a result, the outer edges of the reference part and the support part always come into contact with the rim flange part and the bead seat part during measurement, so that the bead inclination angle measuring device is not displaced in the wheel axis direction. The versatility can be improved while maintaining high measurement accuracy.
[0016]
Further, the outer edge of the support part, the outer edge facing the rim flange part and bead seat part of the rim to be measured, can be in close contact with the coupled curved part extending from the rim flange part of the rim to the bead seat part. (3) is proposed.
[0017]
With this configuration, when the bead inclination angle measuring device is placed on the rim, the support portion comes into close contact with the coupled curved portion, so that the bead inclination angle measuring device is stably placed on the rim. The measurement accuracy is further improved.
[0018]
In addition, as a movable measurement part, what is comprised by the movable part of a dial gauge can be proposed (Claim 4). With this configuration, the bead inclination angle can be obtained with a specific numerical value, and the manufacturing cost of the bead inclination angle measuring device can be reduced by using a known technique.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Below, this invention is demonstrated according to FIGS.
FIG. 1 shows a state in which a bead inclination angle measuring device 10 according to the present invention is placed on a rim 1 to be measured. Here, the rim 1 supports a sidewall portion (not shown) of the tire, and an inner end rim flange portion 4a that becomes the vehicle body side when the tire is mounted, and an inner bead seat that is coupled to the inner end rim flange portion 4a. Part 5a is formed. On the other side, an outer end rim flange portion 4b that supports the sidewall portion of the tire and an outer bead seat portion 5b that is coupled to the outer end rim flange portion 4b are formed. The inner end bead seat portion 5a and the outer end bead seat portion 5b described above are inclined downward by 5 ° toward the center of the rim 1, respectively.
[0020]
On the other hand, a bead inclination angle measuring device 10 placed on the rim 1 includes a horizontally long rectangular base body 15 having a reference portion 11 projecting downward, and a thin plate rotatably disposed on the base body 15. The movable support body 12 and a dial gauge 14 are formed.
[0021]
More specifically, the reference portion 11 is formed at one end of the thin plate-like base body 15 and has an inverted triangular shape, and an end portion of the reference portion 11 that contacts the bead sheet portions 5a and 5b of the rim 1. It has become. And when this bead inclination angle measuring device 10 is mounted on the rim | limb 1, this reference | standard part 11 is while the outer edge of a perpendicular direction contacts the inner wall of the inner end rim flange part 4a among the outer edges. The lower end thereof comes into contact with the inner bead sheet portion 5a.
[0022]
On the other hand, when the bead inclination angle measuring device 10 is placed on the rim 1 at the other side end of the base body 15, the outer end rim flange portion 4b and the outer bead seat portion 5b come into contact with each other. A support 12 is disposed. The movable support 12 is pivoted about the support shaft 17 provided at the upper end thereof so as to be rotatable in the wheel axis direction of the rim 1 to be measured with respect to the base body 15.
[0023]
Further, the movable support 12 is connected to the base 15 via a compression spring 16 at a position below the support shaft 17. The compression spring 16 is disposed inside the base body 15 so that the expansion / contraction direction is substantially parallel to the wheel axis direction. When the lower end of the movable support 12 is pushed toward the base body 15 along the wheel axis direction, When the urging force is generated and the pushing force is released, the lower end of the movable support 12 returns to the original position according to the elastic force of the compression spring 16.
[0024]
Moreover, the outer edge which faces the outer end rim flange part 4b and the outer bead seat part 5b among the outer edges of the movable support 12 is formed in the coupled curved part 8 from the outer end rim flange part 4b to the outer bead seat part 5b. It is molded so as to have a shape that substantially matches the shape. That is, by setting it as the above-mentioned structure, while the outer edge of the movable support body 12 closely_contact | connects with the coupled curved part 8, it will elastically contact the outer end rim flange part 4b and the outer side bead seat part 5b. In addition, the support part concerning this invention is comprised by the movable support body 12 concerning this embodiment example.
[0025]
Further, a dial gauge 14 is disposed between the reference portion 11 and the movable support 12. The dial gauge 14 includes a movable portion 13 that moves up and down in the vertical direction and that has a lower end in contact with a measurement target. And the displacement amount of the lower end of the movable part 13 is detected, and the result is displayed on the measurement display part 18 provided in the main body 19. As the dial gauge 14, a known one is preferably used.
[0026]
In the dial gauge 14, the shortest distance between the vertical line p (see FIG. 4) related to the movable portion 13 and the lower end of the reference portion 11 is separated by a predetermined length (hereinafter referred to as a measurement portion separation distance D). Arranged in position. More specifically, as shown in FIG. 1, when the lower end of the reference portion 11 is brought into contact with the inner bead sheet portion 5a and the lower end of the movable support 12 is brought into contact with the outer bead sheet portion 5b, As shown in FIG. 4, the lower end of the movable portion 13 of the dial gauge 14 is disposed within the range of the measurement portion separation distance D on which the lower end of the movable portion 13 of the dial gauge 14 can come into contact .
[0027]
As shown in FIG. 2, a dial gauge groove 14 a into which the dial gauge 14 is inserted is formed inside the base body 15 so as to penetrate in the vertical direction. The dial gauge 14 is inserted into the dial gauge groove 14a, and the bolt 20 (see FIG. 1) crossing the base body 15 is tightened to fix the dial gauge 14 to the base body 15. In such a case, the lower end of the movable part 13 of the dial gauge 14 in an unmeasured state is located sufficiently below the virtual line k (see FIG. 3) connecting the lower end of the reference part 11 and the lower end of the movable support 12. To be fixed. When the lower end of the movable portion 13 is measuring state by relatively moving while contacting the measurement object, the vertical distance between the virtual line k and the position after the movement of the movable portion 13 lower end, measurement display of the dial gauge 14 It is preset so as to be displayed on the part 18. In addition, the movable measurement part concerning this invention is comprised by the movable part 13 of the dial gauge 14 concerning this embodiment.
[0028]
As shown in FIG. 2, a compression spring groove 16 a in which the compression spring 16 is disposed and a support groove 12 a in which the movable support body 12 is disposed are also formed inside the base body 15. Has been. The compression spring groove 16a and the support groove 12a are connected to each other, and one side of the support groove 12a is an open end. In this configuration, after the compression spring 16 is inserted into the compression spring groove 16a formed in the wheel axial direction, the movable support body 12 is interposed in the support body groove 12a, and the support body 12 crosses the base body 15. It pivots with respect to the base | substrate 15 through the support shaft part 17 provided in the direction. Further, the inner edge of the movable support 12 is connected to the outer edge of the compression spring 16.
[0029]
As described above, the bead inclination angle measuring device 10 can be easily measured because each component is disposed on the base body 15 and integrated.
[0030]
By the way, in a state where no external force is applied to the movable support body 12, the outer edge of the reference portion 11 that contacts the inner end rim flange portion 4a and the outer side of the movable support body 12 that contacts the outer end rim flange portion 4b. The distance L1 (see FIG. 3) from the edge is set to be slightly larger than the rim width L2 (see FIG. 6). In the present embodiment, the separation distance L1 is set to be 4 mm larger than the rim width L2. This value is preferably determined within a range of about 3 to 5 mm.
[0031]
Next, a method for measuring the bead inclination angle θ using the bead inclination angle measuring device 10 will be described. Here, as shown in FIG. 4, the bead inclination angle θ refers to the inclination angle of the bead seat portions 5 a and 5 b with respect to the wheel axis direction of the rim 1 to be measured, and specifically, with respect to the virtual line k. It is expressed as an inclination angle.
[0032]
First, as shown in FIG. 1, the rim 1 to be measured is fixed so that the wheel axis direction is horizontal.
[0033]
Next, the bead inclination angle measuring device 10 is interposed between the rim flange portions 4 a and 4 b of the fixed rim 1. Here, since the distance L1 between the outer edge of the reference portion 11 and the outer edge of the movable support 12 is slightly larger than the rim width L2, the movable support 12 is resisted against the elastic force of the compression spring 16, The bead inclination angle measuring device 10 is interposed while being pushed into the base 15 side.
[0034]
Then, the lower end of the reference portion 11 is brought into contact with the outer bead sheet portion 5a, and the lower end of the movable support 12 is brought into contact with the inner bead sheet portion 5b. Here, the movable support 12 is brought into close and elastic contact with the coupled curved portion 8 by the action of the compression spring 16.
[0035]
When placing the bead inclination angle measuring device 10 on the rim 1, the virtual line k connecting the lower end of the reference portion 11 and the lower end of the movable support 12 is made to coincide with the wheel axis direction, and the dial The movable part 13 of the gauge 14 is placed so as to be displaced along the vertical line p. Here, as means for confirming whether or not the movable portion 13 of the dial gauge 14 is in an appropriate state, as shown in FIG. 5, the bead inclination angle measuring device 10 is set to the B state or the C state. A configuration in which the state in which the measured value obtained by the dial gauge 14 is the minimum among the tilted and tilted times is set to an appropriate state A is preferable. By using the dial gauge 14, it becomes easy to obtain an appropriate measurement state.
[0036]
By the way, since the lower end of the movable part 13 of the dial gauge 14 in the unmeasured state is fixed to the base body 15 so as to be sufficiently below the virtual line k in advance, the reference part 11 and the movable support 12 are connected to each other. Before being brought into contact with each bead sheet portion 5a, 5b, the inner bead sheet portion 5a is first contacted .
[0037]
Then, after the bead inclination angle measuring device 10 is properly placed on the rim 1, the measurement value displayed on the measurement display unit 18 of the dial gauge 14 is read. This measurement value corresponds to the vertical distance x of the lower end of the movable portion 13 with respect to the virtual line k represented by x in FIG.
[0038]
Here, the bead inclination angle θ is
tan θ = x / D
It will be expressed as Therefore, it is possible to obtain the bead inclination angle θ by substituting the measurement unit separation distance D predetermined at the time of manufacturing the measuring instrument and the measurement value (vertical distance x) obtained by the dial gauge 14 into the above equation. Become. The dial gauge 14 may store a program for calculating the bead inclination angle θ from the vertical distance x based on the above equation, and the measurement display unit 18 may directly display the bead inclination angle θ.
[0039]
Further, the inventor of the present invention has a measurement method using a plate gauge and a measurement method using a three-dimensional measuring instrument, and a measurement method using the bead inclination angle measuring device 10 according to the present invention. We compared the measurement accuracy. Specifically, the bead inclination angle θ of the rim to be a test body was measured at 25 points (n = 25) by each measurement method.
[0040]
First, the standard deviation of the measurement value in the measurement method using a plate gauge was σ = 0.526, and the standard deviation of the measurement value in the measurement method using a three-dimensional measuring device was σ = 0.275. . On the other hand, the standard deviation of the measured value in the measuring method using the bead inclination angle measuring device 10 according to the present invention was σ = 0.168. Therefore, the standard deviation of the measurement method using the bead inclination angle measuring device 10 is improved by about 68% compared with the measurement method using the plate gauge, and improved by about 32% compared with the measurement method using the three-dimensional measurement device. As is apparent from these results, the measurement method using the bead inclination angle measuring device 10 according to the present invention greatly improves the measurement accuracy as compared with the conventional configuration.
[0041]
Further, as described above, the movable support 12 of the bead inclination angle measuring device 10 is disposed on the base body 15 via the compression spring 16 so that the outer edge of the reference portion 11 and the outer edge of the movable support 12 are separated. Since the distance L1 is configured to be slightly larger than the rim width L2, the outer edges of the reference portion 11 and the movable support 12 always abut against the inner walls of the rim flange portions 4a and 4b during measurement. Even if an error occurs in the rim width L2 between different rims 1, the bead inclination angle measuring device 10 can be stably placed on the rim 1 each time measurement is performed.
[0042]
Further, by using the dial gauge 14, the bead inclination angle θ can be known with a specific numerical value, so that the inspection result in the proper inspection process of the bead inclination angle θ is fed back to other equipment such as a mold. This makes it extremely easy to improve maintenance functions. In addition, the tendency and ability of the product (rim 1) can be easily grasped.
[0043]
In addition, although the embodiment described so far shows a configuration for measuring the bead inclination angle θ of the inner bead sheet portion 5a, the bead inclination angle θ of the outer bead sheet portion 5b is similarly measured. Of course you can.
[0044]
【The invention's effect】
The bead inclination angle measuring device of the present invention includes a base, a rim flange portion on one side, and a reference portion that makes contact with the bead seat portion, a rim flange portion on the other side, and a support portion that makes contact with the bead seat portion, respectively. The lower end is displaced along the vertical direction, and the movable measurement unit is in contact with the bead sheet unit with which the reference unit abuts, and the lower end of the movable measurement unit with respect to an imaginary line connecting the lower end of the reference unit and the lower end of the support unit. Since the tilt angle of the bead seat portion with respect to the imaginary line is measured from the vertical distance (Claim 1), the bead tilt angle measuring device can be stably placed on the rim, and the measurement accuracy is greatly improved. And the excellent effect of improving the reproducibility and repeatability of the inspection process. In addition, compared with the measuring method using a plate gauge, the number of man-hours is not increased, so that a complicated inspection process is not required. In addition, since each component is arranged integrally with the base body, the overall configuration is simple, and convenience is good.
[0045]
Further, when the movable support is disposed on the base body through at least a compression spring, and the movable support is configured to be elastically contacted with the rim flange portion and the bead seat portion (Claim 2), each measurement is performed. Even when the rim width changes due to rim errors, the outer edges of the reference portion and the support portion are always connected to the rim flange portion and the bead seat portion due to the action of the compression spring. Since each contact | abuts, a bead inclination-angle measuring device does not shift | deviate in a wheel-axis direction, and there exists an effect which can improve versatility, maintaining a high measurement precision.
[0046]
Further, the outer edge of the support part, the outer edge facing the rim flange part and bead seat part of the rim to be measured, can be in close contact with the coupled curved part extending from the rim flange part of the rim to the bead seat part. In this case (Claim 3), when the bead inclination angle measuring device is placed on the rim, the support portion comes into close contact with the coupled curved portion, so that the bead inclination angle measuring device is stable on the rim. The measurement accuracy is further improved.
[0047]
Further, when the movable measuring part is constituted by a movable part of a dial gauge which is a known technique (Claim 4), the bead inclination angle can be obtained with a specific numerical value, and the bead inclination angle measuring device can be obtained. There is an advantage that the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a front view of a bead inclination angle measuring device 10 placed on a rim 1;
FIG. 2 is a bottom view of a base body 15;
FIG. 3 is an explanatory diagram showing an imaginary line k that connects the lower end of the reference portion 11 and the lower end of the movable support 12;
FIG. 4 is an explanatory diagram showing a bead inclination angle θ.
FIG. 5 is an explanatory diagram showing a measurement mode of a bead tilt angle measuring method using the bead tilt angle measuring device 10;
6 is a longitudinal sectional view of the rim 1. FIG.
FIG. 7 is a view showing how a general plate gauge G is used.
FIG. 8 is an explanatory diagram of a method for measuring a bead inclination angle using plate gauges G1 and G2, in which a is a case where a plate gauge G1 corresponding to the maximum appropriate inclination angle is used, and B corresponds to a minimum appropriate inclination angle. The case where plate gauge G2 is used is shown.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rim 4a Inner end rim flange part 4b Outer end rim flange part 5a Inner bead seat part 5b Outer bead seat part 8 Compound curved part 11 Reference part 12 Movable support body 13 Movable part 14 Dial gauge 15 Base 16 Compression spring k Virtual line x Vertical distance θ Bead tilt angle

Claims (4)

A substrate;
Projecting downward from the base body, one rim flange portion formed on the rim to be measured, and a reference portion abutting on each of the bead seat portions coupled to the rim flange portion;
A rim flange portion on the other side formed on the rim, and a support portion that abuts each of the bead seat portions coupled to the rim flange portion;
It is disposed between the reference portion and the support portion, and the lower end is displaced along the vertical direction, and at a required position, the movable measurement portion that comes into contact with the bead sheet portion with which the reference portion abuts,
A bead inclination angle measuring device for measuring a vertical distance of a lower end of a movable measuring unit with respect to an imaginary line connecting a lower end of a reference unit and a lower end of a support unit. The support portion is constituted by a movable support body that is separate from the base body, and the movable support body is disposed on the base body through at least a compression spring,
2. The bead inclination measuring device according to claim 1, wherein the movable support is elastically contacted with the rim flange part and the bead seat part to measure the inclination angle of the bead seat part.   Of the outer edges of the support part, the outer edge facing the rim flange part and the bead seat part of the rim to be measured is shaped so as to be in close contact with the coupled curved part from the rim flange part of the rim to the bead seat part. The bead inclination angle measuring device according to claim 1 or 2, wherein   The bead inclination measuring instrument according to any one of claims 1 to 3, wherein the movable measuring unit is configured by a movable part of a dial gauge.

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