JP4610492B2 - Vehicle wheel - Google Patents

Description

  The present invention relates to a vehicle wheel for automobiles, agricultural vehicles, industrial vehicles and the like, and more particularly to a vehicle wheel in which a disk is fitted and welded to a drop portion of a rim.

As a so-called two-piece steel wheel, a wheel that welds and joins a disc and a drop portion of a rim is known. With respect to this type of wheel, the present inventors have proposed a technique capable of reducing the disk shape and reducing the weight (for example, see Patent Document 1). In this technique, as shown in FIG. 7, the outer edge of the steel disk 100 is folded back and extended inward along the axial direction to form a flange 100a, and the outer surface of the flange is fitted to the inner surface of the drop portion 20c of the rim 20. Then, arc welding (W100) is performed on the inside of the fitting portion 50 of the both.
Note that “outer side” refers to a portion on the outer surface side as viewed from the axial direction of the wheel when the wheel is attached to the vehicle, and “inner side” refers to the inner surface side.

This technique pays attention to the fact that the welding strength can be sufficiently secured even when the welding length is short by using arc welding, and the edge of the ventilation (drainage) S of the disk 100 is used as the edge of the disk rising portion (flange). The disk is made lighter by taking a large arc shape recessed outward in the axial direction from the edge 100b. Therefore, welding is not performed in the ventilation S. Further, in this technique, the outermost portion 100c of the edge of S is positioned outside the edge 100b (corresponding to the distance h in FIG. 7) to reduce the wheel shake.
Here, the water drain hole discharges water and mud accumulated in the inner space of the wheel surrounded by the disc and the rim, improves the wheel balance, and dissipates heat generated from the brake inside the wheel.

  In addition, this technology increases the degree of freedom in setting the fitting length m of the rim and disk by the amount that the welding strength is secured by arc welding, so the optimum m dimension (3 to 40 mm) is adopted and the durability strength is increased. Can be improved. Here, m is the distance between the R center of the curved portion 20b that connects the drop portion 20c and the outer sidewall portion 20a of the rim 20 and the edge 100b. In this technique, the edge 100b is located on the inner side of the R center. To position.

On the other hand, the disc and the rim drop part are not welded, but the cast disk is fitted to the inner surface of the outer bead sheet of the rim formed by forming the plate material, and the outer circumference of the fitting part is welded to the entire circumference fillet. A technique for manufacturing an aluminum wheel is disclosed (for example, see Patent Document 2). According to this technique, since the outer flange is formed of a plate material rim separate from the disk, the rim is not damaged by an external force as compared with an aluminum wheel in which the disk and the rim are integrally cast.
However, this technique is a so-called semi-full design in which a disc having no recess, such as the ventilation S, is fitted to the inner peripheral surface of the outer bead seat of the rim, and the outer periphery of the fitting portion is welded on the entire circumference. It is a wheel called a wheel and relates to an aluminum wheel, and no drain hole is formed as in the steel wheel.
Japanese Patent No. 3460764 Japanese Unexamined Patent Publication No. 7-32805

However, in the case of the technique described in Patent Document 1 described above, since the welded portion is still the lowest strength part, it is difficult to reduce the disk thickness and the weight of the wheel is not sufficient. Further, in order to maintain the disc strength at or above the standard value, an appropriate combination of the m dimension, the h dimension, and the weld length is required, and the degree of freedom for setting these is limited. Here, the m dimension is a distance between the edge of the flange of the disk and the R center of the curved portion corresponding to the shoulder of the outer drop portion of the rim. The h dimension is the distance between the innermost part of the arc-shaped concave part of the drainage S of the disk and the R center of the curved part.
In addition, when the disc strength (rigidity) is reduced, the followability of the vehicle body to the turning of the steering wheel during vehicle operation may be reduced, and the steering stability of the vehicle may be deteriorated. For this reason, in the case of the above-described technology, there arises a problem that the weight of the disk is limited in order to ensure the disk rigidity and the weight loss is limited.

  On the other hand, the technology described in Patent Document 2 relates to an aluminum wheel in which the disc is thick and integrally cast as described above, and the disc without the recess is fitted to the inner peripheral surface of the outer bead seat of the rim. This is related to the so-called semi-full design wheel that welds the outside of the fitting part to the whole circumference fillet. Different. Furthermore, this technique is intended to improve the strength of the flange of the rim portion, and has not been studied for improving the strength of the steel disk.

  The present invention has been made to solve the above problems, and in a vehicle wheel formed by fitting and welding a disc to the outside of a drop portion of a rim, the welding strength and durability of the wheel can be improved. The object is to provide a vehicle wheel that can be reduced in weight.

In order to achieve the above object, a vehicle wheel according to the present invention has a diameter reduced from an outer side wall portion through a curved portion through an outer bead seat, a rim having a drop portion parallel to the axial direction, and an outer edge as an axis. And a disk having a flange that is folded inward along the direction, and a recess having a diameter smaller than that of the flange is formed on an outer edge of the disk, and an edge of the recess is recessed axially outward from the edge of the flange. The outermost portion of the end edge of the concave portion that is in an arc shape is located outside the R center of the curved portion, and the fitting portion between the outer inner peripheral surface of the drop portion and the outer peripheral surface of the flange among some of only the outer portion of the rim and the disc except the portion which does not contact the recess is welded, outside the position edge of said flange toward 15mm inward from R center of the curved portion Characterized by position.
In this case, since the outer portion of the fitting portion between the drop portion and the flange is welded, even if a stress is applied to expand the fitting surface in the radial direction while the wheel is rotating, the drop portion and the flange As in the case where the inner part of the fitting part is welded, an excessive stress is not applied to the welded part by the principle of the insulator, and the strength of the welded part is improved.
In the present invention, since the outer portion of the fitting portion forms a V-shaped groove, welding is easy and reliable, and the welding strength is improved.
In addition, since the disk material plate can be small, and the notch area of the recess is increased, the weight of the disk can be reduced. In addition, when the outermost portion described above is located at a position of 5 mm or more outside the R center of the curved portion, the portion is spaced apart from the R center in the axial direction. When one is formed, it is suppressed that one of them comes into contact with the rim and a rigidity imbalance is generated, so that the shake of the wheel can be suppressed.

It is preferable that the endurance strength defined by JIS D 4103 “Automotive parts—disc wheel—performance and display” is satisfied.
By satisfying the durability specified by JIS, it can be applied to all vehicle wheels including automobile wheels.

It is preferable that the outer peripheral surface of the flange is shaved so as to conform to the shape of the outer peripheral surface of the drop portion.
In this way, the contact with the inner peripheral surface of the rim becomes tighter, the fitting area between the rim and the disk increases, welding can be performed more reliably, and the wheel runout accuracy is improved.

It said that from the fitting portion spread angle of the groove which is formed toward the outside, it is preferable that the outer peripheral surface or outer the peripheral surface of the drop portion of the flange is cut.
If it does in this way, the penetration depth of welding can be deepened and welding can be performed reliably.

  ADVANTAGE OF THE INVENTION According to this invention, in the vehicle wheel formed by carrying out the fitting welding of the disk on the drop part outer side of a rim, the welding strength and the durable strength of a wheel can be improved, and the weight reduction of a wheel can be achieved.

Hereinafter, embodiments of the present invention will be described. In the following description, a steel wheel is exemplified, but in the present invention, in addition to the steel wheel, a material that can be formed into a disk by forming the flange by folding the outer periphery of the plate material by drawing or the like (for example, titanium, titanium alloy) Can be targeted.
On the other hand, since aluminum, magnesium, etc. have higher specific strength than steel, etc., it is normal to produce a thick disk integrally by casting, and there are few problems of strength reduction around the decorative hole. In the present invention, such a cast (forged) disk integrally formed with a thick wall is not intended.
Further, the wheel according to the present invention is intended to reduce the weight of the wheel by improving the welding strength, and preferably satisfies the official definition of durability. However, the present invention can be applied to an industrial vehicle (agricultural) wheel or an emergency wheel (including an automobile temper wheel) that does not have an official durability strength regulation.
Here, the official endurance strength is JIS D 4103 “Auto Parts-Disc Wheel-Performance and Display” in Japan. If the standard changes in the future, the Japanese Industrial Standard JIS (and / or Refers to the official durability of a wheel determined by the International Organization for Standardization (ISO).

FIG. 1 is a cross-sectional view showing an example of a vehicle wheel according to an embodiment of the present invention. The vehicle (steel) wheel according to the embodiment of the present invention is a wheel formed by fitting a steel rim 2 and a steel disk 10 to the outside of a drop portion of the rim and welding them.
In the following description, “outside” refers to a portion that is on the outside when the wheel is mounted on the vehicle, and “inside” refers to a portion that is on the inside .
Further, the radial direction of the rim and the disk is expressed as “inner peripheral surface” or “outer peripheral surface”.

1) Rim The rim 2 has a substantially cylindrical shape and accommodates a tire between an outer flange and an inner flange formed at both ends thereof. An outer bead sheet for receiving the tire bead is formed inside the outer flange. The drop part 2c having the smallest diameter is formed inside the outer bead sheet, and the outer bead sheet and the drop part (outer part) 2c are smoothly connected via the sidewall part 2a. The drop part 2c and the sidewall part 2a are connected via a curved part 2b having a semicircular cross section. An inner bead sheet is formed inside the drop part 2c via a sidewall part, and the inner bead sheet is connected to the inner flange. In the following description, the “drop portion” refers to the outer portion of the drop portion (the portion connected to the outer bead sheet).
The rim 2 can be produced, for example, by rolling a rolled shape steel having a predetermined shape into a cylindrical shape, or after rolling a steel plate into a cylindrical shape, it may have a predetermined cross-sectional shape by roll forming or the like. It is not limited to the method.

2) Disc The disc 10 has a substantially disk shape, a hub hole is opened at the center, and a bolt hole for mounting the hub is formed on the outer peripheral side from the hub hole.
The outer edge of the disk is folded inward along the axial direction to form a flange 10a, and the flange 10a reaches the flange end edge 10b.
The disk 10 can be formed by, for example, drawing (pressing) a square steel plate having four corners punched into a circle (see FIG. 3 of Patent Document 1). In this case, as shown in FIG. 2, the portion of the steel plate punched out into a circle becomes the flange edge 10 a of the disk, and the other portion of the steel plate becomes the recess 11. The concave portion 11 is formed with a diameter smaller than that of the flange 10a, and the end edge of the concave portion 11 has an arc shape that is recessed outward in the axial direction from the end edge 10b of the flange, and the innermost portion 10c is formed near the outermost center.

FIG. 3 is a partial front view of the vehicle steel wheel of FIG. In this figure, a recess 11 having a diameter smaller than that of the flange 10a is formed on the outer edge of the disk 10. The recesses 11 are formed at positions obtained by dividing the disk outer circumference circle into four equal parts.
When the innermost portion 10c is located outside the R center of the curved portion, when the disc 10 is fitted to the inner peripheral surface of the drop portion 2c of the rim 2, the recess 10 and the inner peripheral surface of the drop portion 2c are interposed. A gap is formed, which becomes the drain hole 12.

  In addition, a plurality of circular decorative windows 10e are opened on the inner circumference of a predetermined distance from the outer edge of the disk. The decorative window 10e is usually formed for weight reduction and heat dissipation.

  A valve hole 15 is formed at the end of the rim. When the disk 10 and the rim 2 are welded, the weld bead approaches the valve hole 15 to prevent the hole edge from being melted. It is preferable to adjust the fitting position of the disk 10 and the rim 2 so that the drain holes 12 face each other.

3) Welding Next, a mode in which the rim 2 and the disk 10 described above are fitted and welded together will be described with reference to FIGS. 1 and 4. FIG. 4 is a partially enlarged view of FIG.
In FIG. 1, the outer peripheral surface of the flange 10a of the disk 10 is fitted to the inner peripheral surface of the drop portion 2c of the rim 2 to form a fitting portion. And the outer part 5 of a fitting part is welded (welding part W), and the rim | limb 2 and the disk 10 are joined. Here, the distance between the edge 10b of the flange 10a and the R center of the curved portion 2b is m.
FIG. 4A shows a case where m> 0 (end edge 10b is located on the inner side of the R center). In this case, since the fitting length (the length in the axial direction) between the flange 10a and the rim 2 is increased, it is possible to secure strength in the entire joint structure and to suppress vibration. Also, depending on the size of the disc and rim, the fitting length can be adjusted as appropriate to balance the strength of the disc and rim, thereby improving the durability of the wheel. On the other hand, when m increases, an extra fitting length is generated and the wheel weight increases.
For this reason, the upper limit of m is set to 15 mm in the present invention. That is, the flange edge 10b is located outside the position 15 mm inward from the R center of the curved portion.

FIG. 4B shows a case in which fitting is performed so that m ≦ 0 (the edge 10b is located at the same position as the R center or outside). In this case, since the fitting length (axial length) between the flange 10a and the rim 2 is shortened, the effect of improving the strength by the joint structure is reduced. Wheel strength can be maintained. Since m can be reduced, the wheel weight is reduced. The value of m in this case varies depending on the dimensions of the wheel, but can be, for example, m = −5 mm to −3 mm.
When m ≦ 0, the disc may be fitted using a predetermined jig so that the disc is not fitted obliquely to the rim.

4) Action In the present invention, since the outer portion 5 of the fitting portion is welded, the strength of the welded portion is improved as compared with the case where the inside of the fitting portion (welded portion W100 in FIG. 7) is welded as in the conventional case. To do. The reason can be considered as follows. First, since the rotating disk is distorted in an elliptical shape, a stress is applied in the radial direction of the disk (the left-right direction in FIG. 1) that widens (opens to the left and right) the fitting portion between the disk 10 and the rim 2. For this reason, when the inside of the fitting part is welded, the stress that expands the fitting part is transmitted from the outside of the fitting part (50 in FIG. 7) to the welded part (W100 in FIG. 7). This is thought to increase the stress applied to the weld.
On the other hand, when the outside of the fitting portion (W in FIG. 1) is welded, the stress that expands the fitting portion is only directly applied to the welded portion outside the fitting portion, and the stress applied to the welded portion has been conventionally Compared to lower.
Therefore, in the present invention, the welding strength can be ensured as compared with the conventional case. As a result, the durability of the wheel is improved, so the disk thickness is reduced by that amount, or the area of the notch by the recess (11 in FIG. 2) is increased to reduce the weight of the disk, and thus the wheel. can do.
Further, depending on the combination of the disc thickness, the area of the recess, the m dimension, etc., the welded portion may not be welded all around. That is, in the present invention, since the stress applied to the welded portion is reduced, a sufficient weld strength may be ensured even in intermittent welding depending on the combination of the disk thickness, the area of the recess, the m dimension, and the like.

  Further, in the outer portion 5 of the fitting portion, a V-shaped groove is formed between the inner peripheral surface extending from the curved portion 2b to the outer sidewall portion 2a and the outer peripheral surface extending from the flange 10a to the outer side of the disk. Therefore, welding to the outer portion 5 becomes easy and reliable, and the welding strength is improved.

  Further, if the outer portion of the fitting portion is welded, it is considered that the stress amplitude around the decorative hole of the disk is reduced. In general, the weakest part of the wheel (disk) is the edge of the decorative hole. Therefore, if the stress amplitude around the decorative hole is reduced, the disk strength can be improved, and the disk can be made thinner and lighter. In addition, when the disc strength (rigidity) is increased, the followability of the vehicle body to the turning of the steering wheel during vehicle operation is improved, and the steering stability of the vehicle is also improved. And, since the distortion also decreases when the stress at the edge of the decoration hole decreases, it can be considered that the disk rigidity is improved.

Incidentally, the welding method is not particularly limited, for example, CO ₂ - arc welding, MAG welding, can be used submerged arc welding, and TIG welding. However, since the welding portion is the wheel outer surface, it is the appearance preferred weld bead surface using a clean TIG welding. In particular, hot wire TIG welding or submerged arc welding is preferable in terms of cost, weld strength reliability, and appearance.

When the distance between the innermost part 10c of the recess 11 and the R center of the curved part is h, it is preferable that the edge of the innermost part 10c is located outside the R center (h> 0).
In this case, the disk material plate can be made small for the same reason as the technique described in Patent Document 1, and the notch area of the recess 11 is increased, so that the disk is lightened. h is preferably 5 mm or more. The reason for this is the same as in the technique described in Patent Document 1, and since the innermost part 10c is spaced apart from the R center in the axial direction, when a plurality of recesses are formed in the disk, one of them contacts the rim. This is because the occurrence of rigidity unbalance is suppressed. As a result, wheel shake can be suppressed.

5) Other embodiments
In the present invention, when the drain hole 12 is present, the length of the weld W at one point (the weld length in the outer circumferential direction of the disk 10) is the longest, and the circumference of the flange 10f sandwiched between the adjacent drain holes 12 is long. Although it is the length in the direction, as described above, since the welding strength is sufficiently secured against the stress, it is sufficient that the welding length at one place is 15 mm or more. Therefore, from the viewpoint of wheel strength and productivity, one weld length may be set within the above range.

  Further, as shown in FIG. 5, the outer peripheral surface 14 of the disk flange 10a may be cut so as to conform to the shapes of the inner peripheral surface of the curved portion 2b and the drop portion 2c. FIG. 5 is an enlarged view of a welded portion corresponding to FIG. As a result, the contact between the inner peripheral surface of the rim 2 and the flange 10a becomes tighter, so that the area of the fitting portion between the rim and the disk can be increased and welding can be performed more reliably, and the runout accuracy of the wheel can be improved. . The outer peripheral surface 14 can be cut by, for example, turning.

  Moreover, as shown in FIG. 6, you may scrape the area | region 16 applicable to the outer part of a fitting part among the outer peripheral surfaces of the flange 10a. FIG. 6 is an enlarged view of a welded portion corresponding to FIG. Thereby, the angle of a groove | channel spreads further toward the outer side from the fitting part outer side, the penetration depth of welding is deepened, and welding can be performed reliably. For the purpose of further widening the groove angle, instead of or in addition to the outer peripheral surface 16 of the flange 10a, the region corresponding to the outer portion of the fitting portion on the outer inner peripheral surface of the drop portion is shaved. May be.

It is sectional drawing which shows an example of the steel wheel for vehicles which concerns on embodiment of this invention. It is a perspective view showing a disk. It is a front view showing the steel wheel for vehicles concerning the embodiment of the present invention. It is the elements on larger scale of FIG. It is a figure which shows the form of the fitting part of a disc and a rim | limb. It is another figure which shows the form of the fitting part of a disc and a rim | limb. It is sectional drawing which shows an example of the conventional steel wheel for vehicles.

Explanation of symbols

2 Rim 2a Outer side wall 2b Curved part 2c (Outer side) Drop part 5 Outer part of fitting part 10 Disc 10a (Disc) flange 10b End edge of flange 10c Deepest part (of end of recess) 11 Concave part 12 Water Hole

Claims (4)

A rim having a diameter reduced from an outer side wall portion through a curved portion through an outer bead sheet and having a drop portion parallel to the axial direction, and a disk having a flange formed by folding an outer edge inward along the axial direction. Vehicle wheel,
A recess having a diameter smaller than that of the flange is formed on the outer edge of the disk, and the end edge of the recess has an arc shape that is recessed outward in the axial direction from the end edge of the flange, and is the outermost portion of the edge of the recess Is located outside the R center of the curved portion,
Of the fitting portion between the outer inner peripheral surface of the drop portion and the outer peripheral surface of the flange, only a portion of the outer portion excluding the portion where the rim and the disk do not contact is welded, and the end of the flange The vehicle wheel, wherein an edge is located outside a position 15 mm inward from an R center of the curved portion. The vehicle wheel according to claim 1 , wherein the vehicle has a durability strength defined by JIS D 4103. The vehicle wheel according to claim 1 or 2 , wherein an outer peripheral surface of the flange is cut so as to conform to a shape of an outer peripheral surface of the drop portion. From the fitting portion such that the spread angle of the groove which is formed toward the outside, of claims 1 to 3, characterized in that it is cut within the outer peripheral surface of the outer peripheral surface or the drop portion of the flange The vehicle wheel according to any one of the above.