JP2014043162A - Wheel or wheel cap of non-rotation symmetry pattern and method for creating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly decorative wheel which can form various patterns, hues and designs without being restricted in designs.SOLUTION: In a method for creating a wheel 1 having a disk composed of a design 11 of non-rotation symmetry, rotational balance of the wheel 1 is evaluated by a predetermined rotational balance calculation method, the rotational balance of the wheel 1 is determined to be excellent if the evaluation result is within the range of a predetermined reference value, and a portion of the design is deformed and corrected until the evaluation result is within the range of the predetermined reference value unless the evaluation result is within the range of the predetermined reference value.

Description

  The present invention relates to a wheel or wheel cap used for a wheel of an automobile or the like, and more particularly to a wheel or wheel cap having a non-rotationally symmetric pattern and a method for producing the same.

  Conventionally, a rotationally symmetric pattern is used for a wheel and a wheel cap used for a wheel of an automobile or the like. This is because the centrifugal force generated with the rotation is applied to the rotation center symmetrically and evenly as seen from the rotation center as described later, so that the tire can rotate smoothly.

  If the wheel 1 is not rotationally symmetric, FIG. 18 shows such a pattern as an example, but the opposite force corresponding to the centrifugal force in the direction of the arrow F1 and the direction of the arrow F2 does not work. Therefore, it is pulled with a strong force in the directions of arrows F1 and F2 as it rotates and cannot rotate smoothly. Since it is pulled in a specific direction at a frequency corresponding to the number of revolutions, for example, when a tire having a diameter of 70 cm and traveling at a speed of 60 km is pulled in a specific direction at a frequency of about 7.6 cycles That is, about 7.6 cycles of vibration are generated.

To be precise, centrifugal force is an apparent force. Actually, the force called centrifugal force does not work on a circularly moving object, and the inertial force and the centripetal force that always keeps changing its direction. is working. The size F is expressed by the following equation (1).
F = mrω ² (1)

  Here, m is the mass of the object, r is the distance from the center of rotation of the object, and ω is the angular velocity of rotation (radians / second).

  This centripetal force is balanced with the apparent centrifugal force, and in the present invention, in order to make the explanation easy to understand, the explanation will be made using the centrifugal force hereinafter.

  An example of a conventional wheel having a rotationally symmetric pattern will be described with reference to FIGS. 14 (a), 14 (b), and 15. FIG. Here, FIG. 14A is a schematic view of the wheel 1 composed of the rotationally symmetric disk 3 extending in three directions, and FIG. 14B is a schematic view of the wheel 1 mounted on the tire 5 via the rim 4. FIG. FIG. 15 is a schematic view of the wheel 1 composed of a rotationally symmetric disk 3 attached to the tire 5 and extending in four directions.

  A wheel 1 shown in FIGS. 14 (a) and 14 (b) is composed of a rotating shaft coupling portion 2, a disk 3 extending radially in three directions from the center in a 120-degree rotational symmetry and connected to a rim 4, and a rim 4. The tire 5 is attached to the wheel 1 via the rim 4. The disk 3 shown in FIGS. 14 (a) and 14 (b) shows an example of a shape like a simple rod-like spoke in order to easily understand the present invention, but a flat plate is also used. Can do.

  The disk 3 has an appropriate thickness because it has a function of maintaining strength by being connected to the rim 4 regardless of a flat shape or a spoke shape. It is optional whether the disk 3 has a plate shape or a spoke shape, but in any case, it is common to provide an opening 13 that serves as a decoration and a cooling air port. .

  In the example of the wheel 1 shown in FIGS. 14 (a), 14 (b), and 15, the disk 3 is provided in a rotationally symmetrical manner in three or four directions. Is defined as That is, when n is a positive integer, the property of overlapping the original shape and shape when rotated around a certain rotation center by (360 / n) degrees is n-fold symmetry or n-phase symmetry, (360 / n) It is called degree symmetry. For example, in the case of n = 3, if it is rotated 120 °, the shape overlaps with itself three times, and in the case of n = 4, the shape is overlapped with itself four times when rotated 90 degrees.

  In addition, when n = 1, it is obvious that it rotates 360 degrees and the shape overlaps with itself, so the one-time symmetry is not regarded as symmetry.

  In general, 3 to 8 times symmetrical symbols are often used in automobile wheels, and especially 5 or 6 times symmetrical.

  In many cases, the rotating shaft connecting portion (radius r) 2 of the wheel 1 is connected to the rotating shaft by four or five bolts. In the case of four, only the rotating shaft connecting portion is viewed as a four-fold symmetry, and in the case of five, the same is a five-fold symmetry. In many cases, a symmetrical pattern different from the number of bolts is used in the outer portion. For example, there may be a case where the number of bolts is 5 and the outside is 6 times symmetrical. In such a case, when the rotating shaft coupling part 2 with the bolt is included, there is no n-fold symmetry as a whole, but the wheel 1 rotates stably. That is, even if the radius r from the center of the wheel 1 is 5 times symmetrical and the outside is 6 times symmetrical, the entire wheel has rotational symmetry. FIG. 14A shows an example in which the rotating shaft connecting portion 2 is symmetric five times and the outer side thereof is symmetric three times.

  This can be easily understood by imagining the case where another structure having different rotational symmetry is installed on one rotational axis. Since each attached structure has rotational symmetry, it can be easily imagined that it rotates stably even if it has different values. The above-described rotating shaft connecting portion 2 and the case having a different number of rotational symmetries on the outside are equivalent to the combination of structures having different rotational symmetries.

  In the case of such a symbol, it can be said that it is a non-rotationally symmetric symbol when viewed from the whole wheel, but is completely different from the gist of the present invention, so that it will not be treated as a non-rotationally symmetric symbol in the present invention. It is reasonable to consider these as a combination of a plurality of rotationally symmetric symbols.

  Although prior art documents are shown below, for example, as shown in Patent Document 1, there are some that aim to improve strength and the like, but there is no such thing that the design of the wheel itself is not rotationally symmetric. Patent Documents 3 and 5, which are characteristic in terms of the appearance of the design, are those in which the wheel cover is attached to the wheel so that it can rotate freely, and the design appears to remain stationary even while running. Attach and always stop at the same position when stopped. Patent Document 2 is an example in which a part of the decorative hole of the disk is slightly enlarged, and is an example in which the symmetry is slightly lost in the sense of rotational symmetry, but the purpose is vibration relaxation, and the gist of the present invention is completely different. Different. Patent Document 4 is characteristic in the sense of a design that a night design can be seen with a fluorescent paint, but is not related to rotational symmetry.

JP 2010-132278 A JP 2004-255961 A JP-A-11-245063 Japanese Patent Laid-Open No. 11-78402 JP 11-59102 A Registered Utility Model Publication No. 3055982

  As described above, since all conventional wheels or wheel caps are configured to have a disk with a rotationally symmetric design, the design and design of a wheel or wheel cap made of a rotationally symmetric design is subject to its limitations. As a result, there is a problem that a wheel or a wheel cap having various patterns and designs cannot be configured.

  The present invention has been made to solve the above-described problems, and has a highly decorative wheel or wheel cap capable of forming various patterns and designs without being restricted in design, and a method for producing the same. The purpose is to provide.

  In order to solve the above-described problems, a method for creating a wheel according to the present invention is a method for creating a wheel having a disk made of a non-rotationally symmetric pattern, and the rotational balance of the wheel is evaluated by a predetermined rotational balance calculation method. If the evaluation result is within the range of the predetermined reference value, it is determined that the rotation balance of the wheel is good. If the evaluation result is not within the range of the predetermined reference value, the evaluation result is the predetermined value. A part of the design is deformed and corrected until it falls within the range of the reference value.

  According to the present invention, it is possible to freely design and manufacture a highly decorative wheel or wheel cap having various patterns and designs without being restricted by rotational symmetry. As a result, it is possible to provide a novel wheel or wheel cap that has a function required for a wheel or a wheel cap and has an unprecedented design, texture, or decoration.

The example (1) of the wheel of the non-rotation symmetrical pattern which concerns on embodiment of this invention. The example (2) of the wheel of the non-rotation symmetrical pattern which concerns on embodiment of this invention. The example (3) of the wheel of the non-rotation symmetrical pattern which concerns on embodiment of this invention. The example (4) of the wheel of the non-rotation symmetrical pattern which concerns on embodiment of this invention. The schematic diagram (1) which shows the calculation method of the rotation balance of the wheel of a non-rotation symmetrical pattern. The schematic diagram (2) which shows the calculation method of the rotational balance of the wheel of a non-rotation symmetrical pattern. The schematic table | surface (1) which shows the calculation result of the rotation balance of the wheel of a non-rotation symmetrical pattern. The schematic table | surface (2) which shows the calculation result of the rotation balance of the wheel of a non-rotation symmetrical pattern. The schematic table | surface (3) which shows the calculation result of the rotational balance of the wheel of a non-rotation symmetrical pattern. The schematic diagram which shows the example of a deformation | transformation and correction of a non-rotation symmetrical symbol. The schematic table | surface (1) which shows the recalculation result of the rotation balance of the wheel of a non-rotation symmetrical pattern. The schematic table | surface (2) which shows the recalculation result of the rotation balance of the wheel of a non-rotation symmetrical pattern. The schematic table | surface (3) which shows the recalculation result of the rotation balance of the wheel of a non-rotation symmetrical pattern. (A) is a schematic diagram which shows the conventional rotational symmetry wheel of 3 times object, (b) is a schematic diagram at the time of mounting | wearing the said wheel to a tire. The schematic diagram at the time of mounting | wearing the tire with the conventional rotational symmetry wheel of 4 times object. The figure which shows composition and decomposition of force. (A), (b) is a figure which shows the calculation method of the rotational balance of the conventional rotational symmetry wheel. The schematic diagram of a non-rotation symmetrical wheel.

  Embodiments of a wheel or wheel cap and a method for producing the same according to the present invention will be described below with reference to the drawings.

[Constitution]
As described above, the present invention is characterized in that the design of the wheel or the wheel cap can be freely designed. Therefore, in this embodiment, a non-rotationally symmetric symbol is used as the symbol 11, but as specific examples, examples of the non-rotationally symmetric Trump symbol, the Samurai symbol, the Mount Fuji symbol, and the airplane symbol are shown in FIGS. 1 to 4, respectively. .

  These symbols 11 are made of a metal plate such as stainless steel or aluminum alloy. The metal plate can be formed into an appropriate pattern or pattern by a known machining technique or drawing technique.

  Moreover, you may attach the color of the color to the pattern 11. FIG. Recently, a technique for coloring stainless steel with laser light has also been developed. When stainless steel is used as the material of the pattern 11, such a technique can be used.

  The aluminum alloy can also be colored by an anodized composite film treatment defined by JIS or the like, and the pattern 11 can be colored similarly to the above. By coloring, the variation as a pattern becomes very wide and can be varied.

[principle]
First, the force acting on the center point 0 (X axis = 0, Y axis = 0) will be described using a conventional rotationally symmetric design wheel. Before that, the synthesis and decomposition of the force will be described. Next, I will explain the relationship with the balance of rotation with the wheel.

  FIG. 16 shows two forces f1 and f2 having different directions and magnitudes acting on the center point 0. The start point of f1 is 0, the end point is a, the start point of f2 is 0, and the end point is b. Each of f1 and f2 is a force having a magnitude represented by the length of the arrow in the direction of the arrow. These two forces can be combined and considered as one force. It can be represented by a force F connecting 0 to a new vertex C of a parallelogram that can be created with f1 and f2 as sides. In other words, force synthesis is taking the vector sum of these two forces.

  Here, a diagram showing the above force is expressed in a coordinate system. Consider an XY 2-axis orthogonal coordinate system that passes through the force start point 0. Assume that the x component and y component of f1 are f1x, f1y, and f2, and the y component is f2x and f2y, respectively. At this time, let us consider what happens to the x component Fx and the y component Fy of F. Since the pattern oacb is a parallelogram, the X coordinate of the point c is a point obtained by increasing the x component of the point a by the x component = f2x of the point a. In other words, when the force of f2 is translated and drawn from point a, point c is obtained, but the translation is the same as adding only the x component of f2 to a. is there. From the above, Fx = f1x + f2x. Similarly, for the y component, Fy = f1y + f2y.

  From the above, it has been found that when two forces are combined, the x component and y component of the combined force can be represented by the sum of the x components of each force and the sum of the y components. This is also true for a large number of forces. Because, for example, three forces can be obtained by combining two forces as two and one force, and then combining the combined force and the remaining one force. The x component of the generated force is the sum of the x components of the three forces before synthesis, and the y component is also the sum of the y components of the three forces before synthesis. If this method is applied, a larger number of forces can be similarly applied. Therefore, considering the composition of n forces when n is an arbitrary positive integer, the x component of the synthesized force is the sum of the x components of the n forces before synthesis, and the y component is also the same. Similarly, the sum of the y components of n forces before synthesis.

  Next, it is assumed that one force F acting on the zero point exists first. This is broken down into two forces. First, the direction and magnitude of another arbitrary force f1 is determined. Then, the other side of the parallelogram created when F is a diagonal line and f1 is a side is f2, and the force F is decomposed into f1 and f2.

The above shows that force synthesis and decomposition can be performed based on the very basic principle of mechanics.
As can be seen from the shape of FIG. 16, when the forces are combined, f1 and f2 can take any size and direction. However, in the case of the opposite direction, it becomes a straight line and a parallelogram cannot be drawn, but in this case, the force acts in the direction of a large force by a magnitude obtained by subtracting a small force from a large force.

  Also in the force decomposition, an arbitrary direction and size can be selected as long as the parallelogram can be drawn. The parallelogram cannot be drawn in the opposite direction of the force, but this is the opposite of the previous composition, the force in the opposite direction where the difference in force is already the magnitude of the force, and already Consider two forces in the existing direction.

  When a plurality of forces are acting on the center point 0, these forces are synthesized by the method described above. If the force finally becomes 0, there is no force acting on the center point. That is, it can be said that the forces are balanced from the center point.

Let's apply this to wheel 1. Considering a very small point on the disk 3 of the wheel 1, assuming that the mass is m and the distance from the center is r, the centrifugal force F due to this mass point is expressed as mrω ² and the force F acting on the center point is Can think. This centrifugal force F can be decomposed into two orthogonal axes, XY directions, assumed on a plane orthogonal to the rotation axis of the wheel. The reason for considering two orthogonal axes, XY, is to facilitate understanding. Also, it can be said that these two orthogonal axes can be applied even if the two axes are considered in an arbitrary direction since the discussion has been able to proceed regardless of the direction in the discussion so far.

  Considering the minute mass points on all the disks 3 of the wheel 1, taking the sum of the X component and Y component of those centrifugal forces, if each sum is 0, the force acting on the center point 0 is 0, and the rotation balance It can be said that it is removed. Note that the rim 4 in contact with the tire 5 is not described here, but the rim 4 is circular and is in contact with the tire 5, and is excluded because it is a member that has rotational symmetry from the beginning and is balanced in rotation. It is what.

  If the total sum of the X component and Y component of each minute mass point is 0, it is difficult to understand that the rotational balance is achieved, but it is easy to understand, for example, as follows. That is, consider a single vertical axis Y-axis that passes through the center of rotation. For all the minute masses on the right side, if the centrifugal force generated by the minute mass is synthesized, it can be expressed as one force. This is the sum of the X component and Y component of all the minute masses on the right side. It is synonymous with that. Next, if you do the same thing for the left side, it can be expressed as one force in the same way. Finally, if the total for the right half is zero, it can be said that the right and left forces are balanced. This is equivalent to the sum of the X component and Y component of the force generated by the minute mass for the entire wheel being zero.

[Calculation of rotational balance of rotationally symmetric disk]
Based on the above principle, the rotational balance of the wheel 1 having the conventional rotationally symmetric disk shown in FIGS. 14 (a) and 14 (b) will be described with reference to FIGS. 17 (a) and 17 (b).

  As shown in FIG. 17 (a), the disk 3 is installed from the center of the wheel 1 to the rim 4 at intervals of 120 degrees, which is a three-fold symmetrical design. Consider the minute masses m1, m2, and m3 having the same weight at intervals of 120 degrees in the portion of the radius r near the center of the disk 3 in the three directions. As is clear from the shape of the wheel, such a small mass can always be assumed at the same radius and at intervals of 120 degrees even if the radius changes in the disk 3. In another example, if it can be said that the minute masses m1, m2, and m3 are balanced with each other, it can be said that all other possible combinations of the minute masses having the same radius and the same mass are balanced. .

  FIG. 17B shows the minute masses m1, m2, and m3 in FIG. 17A in the XY coordinate system in which the rotation center is zero. In m1, m2, and m3, the centrifugal force of F1, F2, and F3 is illustrated in the figure as acting radially outward. Now, when the position of m1 is inclined by θ degrees from the X axis, the positions of m2 and m3 are respectively θ + 120 degrees and θ + 240 degrees with respect to the x axis.

  Here, the balance of F1, F2, and F3 is confirmed, but F1, F2, and F3 are calculated by dividing into components in the X direction and the Y direction, respectively. The components in the X direction and Y direction for F1 are the same for c, d, and F3 for a, b, and F2, respectively, and the sum of those X components and the sum of the Y components are 0 respectively. Is the condition of balance. That is, the following two formulas must be established.

a + c + e = 0 (2)
b + d + f = 0 (3)
Here, the following formulas are established for a to f, respectively.
a = F1sinθ (4)
b = F1cosθ (5)
c = F2sin (θ + 120 °) (6)
d = F2cos (θ + 120 °) (7)
e = F3sin (θ + 240 °) (8)
f = F3cos (θ + 240 °) (9)

From the above, a + c + e and b + d + f are obtained. F1, F2, and F3 are represented by m1 × r × ω ² , m2 × r × ω ² , and m3 × r × ω ² , respectively, but m1, m2, and m3 are equal because the same weight is assumed. Since r is equal in all three directions, it is naturally equal. Since ω rotates at the same speed at all three locations, it is naturally equal. Therefore, F1, F2, and F3 are also equal. Therefore, when F1, F2, and F3 are F, [a + c + e] + [b + d + f] = F [sin θ + sin (θ + 120 °) + sin (θ + 240 °)] + F [cos θ + cos (θ + 120 °) + cos (θ + 240 °)] 10).

  Here, when the rotational balance of the wheel 1 is achieved, the first half term and the second half term of Expression (10) are each zero.

According to the addition theorem of the trigonometric function, the sine (sin) and cosine (cos) of θ + 120 ° or θ + 240 ° are expressed by the following equation (11).
[A + c + e] + [b + d + f] = F [sin θ + sin θ cos 120 ° + cos θ sin 120 °
+ Sinθcos 240 ° + cos θsin 240 °] + F [cos θ + cos 120 ° cos θ
−sin120 ° sinθ + cos240 ° cosθ−sin240 ° sinθ] (11)

を（１１）式に代入すると、次式（１２）のとおりとなる。

here,

Is substituted into the equation (11), the following equation (12) is obtained.

  As described above, in the three-fold symmetry pattern, the sum of the forces applied to the center is 0 for the components in the X direction and the Y direction for the combination of masses whose positions are equally rotationally symmetric from the center. It was shown that the rotation balance was achieved.

[Calculation method and adjustment method of rotation balance of non-rotation symmetric design wheel]
Next, a method for calculating and adjusting the rotation balance in the case where the wheel 1 has a non-rotationally symmetric pattern will be described with reference to FIGS. 5 to 13 using the non-rotationally symmetric pattern wheel 1 shown in FIG. To do. In this case, the wheel 1 is described as a case in which a non-rotationally symmetric pattern 11, a rim 4 and the like are integrated, that is, a shape in which the non-rotationally symmetric pattern serves as a conventional disk.

(Calculation method of rotation balance)
First, as shown in FIG. 5, the wheel 1 is divided into a plurality of sections by mesh lines (X axis; x1 to xn, Y axis; y1 to yn) at equal intervals. The above-described calculation method is applied to all the minute sections (hereinafter referred to as “unit sections (Ua, b)”) centering on the intersections of mesh lines equal to the area of the sections.

  The reason why the unit section centering on the intersection of the mesh lines is considered is because the coordinates of the unit section are easy to represent. That is, in FIG. 5, for example, the center position of the unit section U2,10 is (2, 10) in terms of the X-axis and Y-axis coordinates, but the section surrounded by the mesh line is the unit section. In the example of FIG. 5, it is an odd number (2.5, 10.5) and is difficult to understand.

Assuming that the unit section is assumed as described above, if the mass is M and the distance from the center of the coordinate system, that is, X and Y is 0 to the center of the unit section is r, the centrifugal force generated by M is Mrω ² The direction is the direction of the arrow drawn from the coordinate center toward the center of the unit section. The magnitude of the centrifugal force Mrω ² depends on M, r, and ω. As another example, assuming a flat disk having a uniform thickness, M is the same area and thickness in any part of the disk. Since it is the same weight, there is no problem as 1. Also, since ω has the same value for the entire disk, there is no problem even if it is considered as 1. Then, the centrifugal force becomes r, and further, when this centrifugal force r is decomposed into XY components, the center coordinates of the unit section itself are obtained. As described above, the unit section for confirming the symmetry is very easy to understand when considering the center of the intersection of the mesh lines.

A and b of the unit sections Ua and b (X-axis position = a, Y-axis position = b) represent the X component and Y component of r, respectively, and have a relationship of a ² + b ² = r ² . For example, in the unit section U2,10 of FIG. 5, a = 2 and b = 10. As described above, the centrifugal force r is decomposed into an x component and a y component. In the present invention, unit zones are assumed for all portions of the wheel symbol, and the respective sums of the X component and Y component of all unit zones are obtained.

  Next, for mesh lines, when actually calculating and adjusting the rotation balance of the wheel, it is provided in the X-axis direction for each unit length, for example, every 5 mm or 1 cm, and in the Y-axis direction at similar intervals. Provide. For a wheel of an automobile or the like, it is preferable to provide a mesh line at a short interval, for example, about several mm, in order to confirm the balance more precisely. Of course, the interval may be as short as about 1 mm.

  In FIG. 5, about 10 mesh lines are shown for easy understanding. Most actual wheels have a diameter of 16 inches or 18 inches, and in this case, the radius is 20 to 23 cm. Therefore, when considering mesh lines at intervals of 5 mm, about 40 mesh lines are shown. However, if 40 lines are described in the figure, the mesh lines are too dense and difficult to see. For convenience, about 10 mesh lines are shown. is there.

  FIG. 6 shows an enlarged view of the first quadrant of FIG. For the X axis and Y axis, mesh lines are shown as 1 to 13, respectively. The unit for 1 to 13 is actually the size of the division for checking the balance as described above, and values such as 1 mm, 5 mm, and 1 cm may be used. The case of 5 mm indicates that there is a mesh line at the position of mesh line number × 5 mm. Here, in order to show an example of a method of calculating and confirming the balance divided into unit sections, numbers 1 to 13 having no units are simply used for convenience.

  A specific example will be described with a large number of unit sections shown in FIGS. As for the display of coordinates, when the values of the X axis and the Y axis are a and b for a certain position, the unit section is expressed as Ua and b, and the mass corresponding to the unit section is as shown in FIG. , Ma, b. In the example of FIG. 6, the location indicating the unit section, that is, the coordinates are (0, 5) (0, 6) --- (0, 11), (1, 12), (2, 12), (3, 12), and the mass of these unit sections is M0, 5, M0, 6,... M0, 11, M1, 12, M2, 12, M3, 12.

  Assuming that the disk 3 having the predetermined pattern 11 is made of a metal plate having a constant thickness, the mass of the unit section is proportional to the area of the metal portion in the unit section. When the unit section is completely filled with metal, the value is (M) obtained by multiplying the specific gravity and thickness of the metal by area 1, but since this is a relative comparison, this reference mass M is set to 1 as already described. There is no problem. In the case where it is partially lacking like the peripheral part, according to the area of the metal part included in the unit section, for example, when the area of M3, 12 is 30% of the unit section, M3, 12 is 0.3 It can be expressed as. As described above, M0, 5, M0, 6, M0, 9, M0, 10, M0, 11, M1, 12, M2, 12, M3, 12 are assigned, for example, 1, 1, from the respective area ratios. ,..., 1, 0.65, 0.05, 0.2, 0.49, and 0.3.

In this way, the entire design part is enclosed so as to be covered by the unit section, and the respective areas are obtained. For the X-axis component, the value obtained by multiplying the X-axis coordinate, and the Y-axis coordinate for the Y component are also obtained. When the multiplied value is obtained, this becomes the X component and Y component of the centrifugal force due to the masses Ma and b. Multiplying the values of the X-axis coordinate and the Y-axis coordinate is to obtain the X component and the Y component from the value of the centrifugal force Mrω ² . This point will be specifically described.

Now, consider the masses M2 and 10 of the unit sections U2 and 10 when a = 2 and b = 10. Since mass M2,10 is the M = 1, ω = 1, the centrifugal force F acting on the mass, the r from the equation F = Mrω ^2. In order to apply even when M is not 1, 1 of M is added and expressed as 1r. In FIG. 5, this is the force F shown by drawing a straight line from the center point 0 of the XY coordinates toward the center point P of the unit section U2,10 of the mass M. At this time, the X component and the Y component of F are expressed as a and b, as is apparent from FIG. Similarly, since M is 0.3 for M3 and 12, the centrifugal force is 0.3r, and a value obtained by multiplying a and b by 0.3, that is, 0.3a and 0.3b are X components, Y component. That is, the value obtained by multiplying the value of M by the value of the XY coordinate is the X component and Y component of the force.

  Next, the sum of the X components and the sum of the Y components are obtained. If the sum of both is 0, it is indicated that the wheel 1 made of the symbol or pattern is in a rotational balance, that is, has dynamic rotational symmetry. Even if the sum is not completely zero, it can be said that there is no practical problem if the sum is a value within a predetermined range close to zero.

  FIG. 7 shows a table in which all parts of the design of FIG. 1 are covered and surrounded by unit sections, and the area of each unit section is obtained. The area is expressed as a relative value, such as 1 when the pattern occupies the entire unit section, and 0.5 when the pattern occupies 50%. In the example of FIG. 7, the horizontal direction indicates −12 to +12 on the X axis and the vertical direction indicates −12 to +12 on the Y axis. However, the present invention is not limited to this, and the unit partition may be increased or decreased as appropriate. From the results of FIG. 7, the result of multiplying the area and the X-axis position for the X component and the sum thereof are shown in FIG. 8, and the result of the multiplication of the Y component and the sum of the Y component in the same way are shown in FIG. Shown in In this example, the sum of the X components is 18.81 as shown in the lower right column of FIG. 8, and the sum of the Y components is 21.17 as shown in the lower right column of FIG.

  In addition, in the edge part of the symbol 11, when the symbol 11 occupies a part of the unit section, strictly speaking, a part of the mass does not exist in the center of the unit section. Therefore, for example, if the area is 0.4, it may not be strictly correct that the mass of 0.4 contributes to the rotational symmetry at the coordinate position of the central portion. However, this can be solved by making the mesh smaller, or by giving fine coordinates more than the mesh line so that the position coordinates become the center of mass of the mass for such a partial mass. It is not a problem.

(Rotation balance adjustment method)
As a result, in the case of this example, the total for the X component is 18.81 and the total for the Y component is 21.17. This is a case where it cannot be said that the state is sufficiently balanced, and a method for adjusting the rotational balance will be described below for this example.

  In this embodiment, the rotation balance is adjusted by deforming or correcting the pattern 11. In the results of FIGS. 7 to 9, since both the X component and the Y component are large on the positive side, the pattern 11 is deformed in a direction in which the mass increases on the negative side. An example is shown in FIG. 10, in which a diamond, which is one pattern of a playing card, is slightly inflated to the left. The spade pattern is also inflated downward. In FIG. 10, the symbol indicated by the dotted line is the symbol before deformation, and the symbol indicated by the solid line is the symbol after deformation.

  FIG. 11 shows an area table for each mesh after deformation. The X and Y components are recalculated based on the deformed pattern 11. The results are shown in FIGS. As a result of the recalculation, the sum of the X components is -0.08 and the sum of the Y components is -0.14, which is an extremely small value, which is a predetermined reference value (for example, -0.2 to +0.2). It can be said that it is within the range and has a sufficiently good rotational balance.

  On the other hand, if the sum of the X component and the sum of the Y component are both outside the range of the reference value as a result of the recalculation by the above modification, the pattern 11 is corrected again, and the sum of the X component and the sum of the Y component are both Also, the correction of the symbol 11 is repeated until it falls within the range of the reference value.

  In the above evaluation method, each numerical value was evaluated as a relative value in order to show the effectiveness of this method. However, JIS is defined for the rotation balance. It is JIS-B-0905-1992: “Rotating machine—Better balance of rigid rotor”, and according to it, the regulation of G40 is defined for automobile wheels and wheel sets. Therefore, in actual wheel production, it is considered that the actual machine should be applied by a method such as determining a more balanced guideline value within the range of JIS standard values.

  In the above embodiment, the calculation method and the adjustment method of the rotation balance by subdivision are explained. However, the present invention is not limited to this, and the rotation balance is calculated using another calculation method such as FEM (finite element method). You may evaluate.

(Function)
Although the non-rotationally symmetric symbol wheel and the method for producing the same according to the present invention have been described above, the idea of the symbol correction in the present invention is completely new for the wheel. That is, in the conventional rotationally symmetric design wheel, in order to balance the rotation, the design elements must basically have the same shape. For example, in the case of 5 starfish-like designs, the rotational balance cannot be achieved unless the shape of each of the radial arms is the same. Therefore, the correction from the unbalanced state means that the five starfish-shaped symbols are corrected so as to have the same shape. It is impossible.

As shown in the above example, the modification of making the underside of the spade pattern slightly larger is easy to implement without losing recognition of the original form of spades, and uses a non-rotationally symmetric pattern. This is a point that can maximize the characteristics of the present invention. In addition to the above example, any number of modifications such as slightly changing the shape of the wings of FIG. 2 to the right can be performed. By such an adjustment method, it is possible to adjust a wheel having an initial rotational balance to have a good rotational balance by imparting rotational symmetry to the entire wheel by deformation / correction of the pattern 11. it can.
In addition, you may perform the deformation | transformation and correction of the pattern 11 including changing the thickness.

  Strictly considering the non-rotationally symmetric design, the conventional wheels are equipped with in-air holes, JWL marks indicating compliance with safety standards, company logo marks, etc. There may be room to think that a non-rotation symmetric design already exists, but these air injection holes, logos, marks, etc. are not treated as wheel designs, and the non-rotation symmetric design of the disc in the present invention Is essentially different.

  In the above embodiment, the disk 3 is made of a flat metal plate, but of course, a metal plate having a different thickness for each location may be used. Also, a three-dimensional shape, for example, a pattern such as a swell for the wings shown in FIG. 2 may be used. In these cases, when the balance is confirmed, the mass of the unit section may be calculated by increasing or decreasing it by the thickness. In addition, depending on the design 11, there may be a design in which the area of a certain part is small. Therefore, it is possible to use a method in which the small part is intentionally thickened to balance the whole.

  When the wheel according to the present embodiment is used, it is preferable in terms of design that the portion of the rotary shaft connecting portion 2 is continuous with the other portions as the symbol 11. Therefore, it is preferable not to be able to see the bolt of the rotating shaft connecting portion, which is often done with conventional wheels, but to provide a removable cover so that the pattern 11 is continuously formed. Of course, there is no problem in terms of functionality even without a cover.

(Modification)
The wheel 1 is an important part that connects the automobile and the tire 5 and is in contact with the ground. Therefore, it is necessary to have sufficient strength characteristics. For example, it is necessary to perform various tests according to the already described JWL standard. In the test according to the JWL standard, it is necessary to perform a rotating bending fatigue test, a radial load endurance test, and an impact test. However, as described so far, the disk 3 of the wheel 1 is composed of only the metal thin plate constituting the pattern 11. It is conceivable that the metal plate having a thickness of 2 or 3 mm lacks the strength. Therefore, it is sufficient to increase the thickness of the metal plate so that the strength is sufficient.

  However, even if the thickness of the metal plate is increased, depending on the design, there may be a case where the portion connected to the rim is not evenly provided. When the strength is insufficient, a thick rear disk 12 may be installed together with the pattern 11 made of a metal plate in order to supplement the strength. In that case, it is good to use the method which installs the pattern 11 of this embodiment in the outer side of the back disk 12 with a thin metal plate. 1 to 4 schematically show the rear disk 12 by dotted lines.

  In the example of FIGS. 1 to 4, the back disk 12 is represented by a dotted line. However, since the strength is ensured, it is preferable to use a disk having a predetermined width and thickness. The rear disk 12 may be designed and manufactured using a rotationally symmetric disk in the same manner as a conventional disk that does not use the asymmetric design of the present invention.

  Further, when the rear disk 12 is installed, if the rear disk 12 is installed so as to be hidden behind the design 11, only the design 11 can be seen from the outside, and the design can be reflected. Further, the number of rotationally symmetric disks 12 may be used, for example, five in the case of FIG. 2, three in the case of FIG. 3, and four in the case of FIG.

  The rear disk 12 can be used not only in a flat plate shape parallel to the right-angle cross section of the axle, but also in a convex shape that bulges outward, and conversely, a concave shape. Many such shapes are also used in the wheel 1 actually used. When the back disk 12 is formed in a concavo-convex shape, the pattern 11 may be concavo-convex so as to follow it, or may not be constrained by the shape of the back disk 12 like a wheel cap described below.

  Further, when the rear disk 12 is installed, it is reasonable to play a role of strength with the rear disk 12, and therefore the symbol 11 is positioned in a decorative manner. Therefore, sensibly, the design 11 is attached to the back disk 12. However, since the design 11 also rotates together with the wheel 1, it needs to be attached with sufficient strength so as not to generate vibrations. Or you may manufacture the back disk 12 and the pattern 11 by integral molding.

In the present embodiment, when the non-rotationally symmetric pattern 11 is attached to the conventional disk, the weight of the pattern is increased as compared with the conventional product, and the extent is as follows. If the same aluminum alloy as the wheel 1 is used for the pattern 11, the specific gravity is about 2.7. The area is assumed to be conservative when the entire surface is covered with metal as an 18-inch wheel, and if the thickness is 2 mm, the radius is 22.9 cm. Weight = [π (wheel radius) ² ] × Thickness × specific gravity = [22.92] ² × 3.14 × 0.2 × 2.7≈889 g, indicating that there is no significant increase in weight. Since this value is a value under a conservative assumption that the entire surface is covered, it is actually expected to be about 500 to 600 g, which is a smaller value.

(Wheel cap)
The above embodiment is a case in which the disk itself is composed of a non-rotationally symmetric pattern, including the case of the pattern 11 integrated with the back disk 12, but the pattern 11 of the present embodiment is used as a wheel cap separately from the disk. You may apply. In this case, only a wheel cap (not shown) having a non-rotationally symmetric design is separately prepared and fitted into the wheel 1.

[effect]
As described above, the design of the wheel, which has conventionally used a rotationally symmetric design, is restricted by making it possible to use a non-rotationally symmetric design and wheel having a good rotational balance. Therefore, it is possible to provide a highly decorative wheel capable of configuring various patterns, colors and designs. Moreover, since a non-rotationally symmetrical pattern and pattern can be used also about a wheel cap, there exists the same effect.

  As a result, a design or pattern having high designability, color and decoration can be adopted as a design of a wheel or wheel cap, which has been mainly inorganic design, so that its commercial value is great.

  In addition to the symbols and patterns shown in FIGS. 1 to 4, for example, various symbols (not shown) such as a human or animal character, a famous building or landscape, an animated character, etc. can be used. It is.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, combinations, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Wheel, 2 ... Rotating shaft connection part, 3 ... Disc, 4 ... Rim, 5 ... Tire, 11 ... Design, 12 ... Back disk, 13 ... Air gap.

Claims (5)

A method of creating a wheel having a disk made of a non-rotationally symmetric pattern,
The wheel rotation balance is evaluated by a predetermined rotation balance calculation method. If the evaluation result is within a predetermined reference value range, the wheel rotation balance is determined to be good, and the evaluation result is the predetermined reference value. If not within the range, a part of the symbol is deformed and corrected until the evaluation result falls within the range of the predetermined reference value.   Assuming an XY two-axis orthogonal coordinate system on a plane orthogonal to the rotation axis of the wheel, the disk is divided into a plurality of mesh unit sections on the plane, and centrifugal force is obtained for each unit section and its X 2. The method for producing a wheel according to claim 1, wherein the rotation balance of the wheel is evaluated by obtaining a component and a Y component, and then obtaining a sum of X components and Y components of all the unit sections.   A method for producing a wheel, wherein the method for producing a wheel according to claim 1 or 2 is applied to a wheel having a rotationally symmetric back disk on the back of a disk made of a non-rotationally symmetric pattern.   A method for producing a wheel cap, wherein the method for producing a wheel according to any one of claims 1 to 3 is applied to a wheel cap.   A wheel or wheel cap produced by the method for producing a wheel or wheel cap according to any one of claims 1 to 4.

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