JP2000158902A - Tire wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the vibrating characteristic of a tire wheel and satisfactorily reduce the interior noise in a wheel constituting the wheel of a motor vehicle in cooperation with a tire by imparting the tire wheel a natural frequency different from that of a vibration transmission system for transmitting vibration to the wheel in the motor vehicle. SOLUTION: In this wheel, curvature radiuses are imparted to each surface of a disc part 10 and a rim part 12. Namely, curvature radius imparting parts 50, 52 are formed on the inside surface and outside surface of the disc part 10 to impart the curvature radiuses so that each circumferential part of the disc part 10 is curved facing to the outside of the body. On the other hand, curvature radius imparting parts 54, 57 formed on the inside surface and outside surface of the rim part 12 impart curvature radiuses so that each circumferential part of the rim part 12 is curved facing toward the rotating center of the wheel. According to this, the primary natural frequency of the wheel can be differed from that of the vibration transmission system, or each primary natural frequency of the tire, suspension, drive shaft, and engine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel constituting a vehicle wheel together with a tire when the tire is mounted, and more particularly to a technique for improving the vibration characteristics of the wheel. .

[0002]

2. Description of the Related Art Various sounds are generated in a running automobile, and these sounds are generally called interior noise. And
This noise in the vehicle is caused by the rotation of the engine (muffled sound, engine noise, etc.), the sound generated in the process of transmitting the power of the engine to the wheels (muffled sound, gear noise, etc.), and the vehicle running. Sound (road noise, wind noise, etc.). Hereinafter, the road noise and the gear noise will be described in detail.

[0003] Road noise is an in-vehicle noise generated when an automobile is traveling on a rough road surface.
It has a frequency of 0 Hz. Road noise, for example, becomes an in-vehicle noise through vibration of a wheel, vibration of a suspension, and vibration of a body panel of a vehicle in this order as a vibration source due to unevenness of a road surface.

There are a plurality of types of gear noise, which can be classified into transmission gear noise and differential gear noise, and rattling noise. The transmission gear noise and the differential gear noise are generated when the gears in the transmission and the differential as the power transmission device of the vehicle are engaged as excitation sources. On the other hand, rattling noise is generated by rattling vibration of the drive system of the vehicle when the engine is idling or running at a constant vehicle speed.
Like the road noise, these gear noises become vehicle interior noises through the vibration of the wheels, the vibration of the suspension, and the vibration of the body panel of the vehicle in this order.

[0005]

Problems to be solved by the invention, means for solving the problems and effects of the invention In order to reduce the noise inside the vehicle, the present inventors have conducted research, and as a result, the following facts have been found. That is, conventionally, it was thought that only the elastic vibration of a tire made of an elastic body was a factor in the vibration of a wheel. However, a wheel made of a rigid body (a “disk wheel” in the sense of being distinguished from a “wheel”) Vibrations (sometimes referred to as "vibrations") are also an important factor.

[0006] Based on this finding, the present invention has been made to improve the vibration characteristics of the tire wheel, thereby reducing the noise inside the vehicle satisfactorily. The wheel is obtained. Each mode is described in the same manner as in the claims, divided into sections, each section is numbered, and described in the form of citing the numbers of other sections as necessary. This is to facilitate understanding of some of the technical features and combinations thereof described in this specification, and the technical features and combinations thereof described in this specification are limited to the following. Should not be interpreted as

(1) A wheel which forms a wheel of an automobile together with a tire when the tire is mounted,
A tire wheel having a natural frequency different from that of a vibration transmission system for transmitting vibration to a wheel of an automobile [Claim 1]. According to this wheel, the natural frequency of the wheel is made different from the natural frequency of the vibration transmission system, so that the vibration of the wheel is suppressed, and as a result, the noise in the vehicle caused by the vibration of the wheel is reduced. Here, the "wheel" can be made of steel or aluminum,
It may be an integral type or a split type in which a plurality of members are combined. The “vibration transmission system” includes tires, suspensions, and the like when the wheels are non-drive wheels, and further includes, when the wheels are drive wheels,
Power sources such as drive shafts, differentials, transmissions, and engines (internal combustion engines) are also included.
The relationship between the "natural frequency" of the wheel and the "natural frequency" of the vibration transmission system is such that the primary natural frequency of the wheel does not match at least the primary natural frequency of the vibration transmission system. Can be set or set so that it does not match any natural frequency of the vibration transmission system.
Any natural frequency of the wheel may be set so as not to match any natural frequency of the vibration transmission system. Further, when implementing the wheel described in this section, when there are a plurality of vibration transmission systems, it is desirable to implement the natural frequency of the wheel so as to be different from any of the plurality of vibration transmission systems, Of the plurality of vibration transmission systems, the vibration transmitted to the wheel can be implemented so as to be at least different from the vibration transmission system (for example, a tire) that is the strongest. (2) The tire wheel according to (1), wherein the natural frequency is made higher than the natural frequency of the vibration transmission system by imparting a curvature to the surface of the wheel.
As a technique to make the natural frequency of the wheel different from the natural frequency of the vibration transmission system, the natural frequency of the wheel is increased by increasing the rigidity of the wheel from the rigidity required to secure the required strength of the wheel. There is a mode in which the frequency is higher than the natural frequency of the vibration transmission system. Here, the technology for increasing the rigidity of the wheel includes a mode in which the thickness of the wheel is increased from the thickness required for securing the required strength of the wheel, and a method for securing the required strength of the wheel. There is a mode in which a reinforcing portion such as a rib which is not necessary for the above is added, and the wheel described in this section can be implemented in any of those modes. However, when adopting the mode of increasing the thickness of the wheel, there is a disadvantage that the weight of the wheel increases. Further, since the addition of the reinforcing portion to the wheel causes a change in the shape of the wheel in addition to an increase in the weight of the wheel, when adopting a mode in which the reinforcing portion is added to the wheel, the reinforcing portion is added to the external portion of the wheel. There is an inconvenience that design restrictions are imposed on the addition of. On the other hand, in the wheel described in this section, the natural frequency is made higher than that of the vibration transmission system by giving a curvature to the surface of the wheel. Therefore, according to this wheel, unlike the case where the natural frequency is increased by increasing the plate thickness, the increase in weight does not become a significant problem, and unlike the case where the natural frequency is increased by adding a reinforcing portion. , Weight increase and design constraints are less of a problem. (3) The wheel has a rim joined to the outer periphery of the disc, and the tire is mounted on the rim. At least one of the surfaces of the disc and the rim has a specific surface of the wheel. A curvature is provided to make the frequency different from the natural frequency of the vibration transmission system.
The tire wheel according to the item (2). In this wheel, if the curvature is given to both surfaces of the disk portion and the rim portion, the natural frequency can be easily increased as compared with the case where the curvature is given only to one of the surfaces. (4) At least the surface of the rim portion of the disk portion and the rim portion is provided with a curvature for making the natural frequency of the wheel different from the natural frequency of the vibration transmission system.
The tire wheel according to the item (3). Comparing the effects on the wheel design by imparting a curvature to the respective surfaces of the disc and the rim, it is clear that when the curvature is applied to the surface of the rim, it is greater than when the curvature is applied to the surface of the disc. It is considered that the influence is small. Therefore, according to the wheel described in this section,
Since the curvature is given to at least the surface of the rim portion of the disc portion and the rim portion, the natural frequency of the wheel can be optimized while minimizing the influence on the design of the wheel. (5) In the center of the vehicle, a hub is mounted, and a rim is joined to the outer periphery of the disc. A wheel constituting a wheel, wherein the disc portion is vibrated in its primary natural vibration mode such that a joint portion of the rim portion and a mounting portion of the hub each become a node. In a conventional wheel, the disk portion is vibrated in its primary natural vibration mode such that the joint portion of the rim portion is a node and the mounting portion of the hub is a belly. If the hub is considered as a vibration source for the wheel, the position of the antinode of the primary natural vibration mode is close to the vibration source. Therefore, the vibration amplitude of the disk part is large, and the noise in the vehicle due to the vibration of the wheels tends to increase. On the other hand, according to the wheel described in this section, the disk portion is vibrated in its primary natural vibration mode such that the joint portion of the rim portion and the mounting portion of the hub become nodes. If the hub is considered as a vibration source for the wheel, the position of the node in the first natural vibration mode can be made closer to the vibration source. for that reason,
According to this wheel, the vibration amplitude of the disk portion is reduced as compared with the above-described conventional wheel, and as a result, the in-vehicle noise caused by the vibration of the wheel is reduced. (6) By providing a curvature to at least the surface of the disk portion, the disk portion has a joint between the rim portion and the mounting portion of the hub in its primary natural vibration mode. The tire wheel according to item (5), which is vibrated as follows. According to this wheel, the vibration amplitude of the disk portion is reduced without substantially increasing the weight or changing the design, and as a result, the in-vehicle noise caused by the vibration of the wheel is reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a more specific embodiment of the present invention will be described in detail with reference to the drawings.

The tire wheel according to the present embodiment forms a front wheel in a four-wheel drive type automobile powered by an engine (internal combustion engine) when a tire is mounted on the tire wheel. FIG. 1 shows the wheel in a front view, and FIG. 2 shows a II-II section in FIG.
As shown in FIG. 2, the wheel has a shape in which a rim portion 12 is joined to an outer periphery of a disk portion 10. The disk portion 10 and the rim portion 12 are integrally formed of aluminum. A hub mounting portion 14 is formed at the center of the disk portion 10. The hub mounting portion 14 has a hub hole 16 at the center thereof and a plurality of hub bolt holes 18 at the periphery thereof. A center ornament (not shown) (made of synthetic resin) is detachably attached to the hub hole 16.

The hub mounting portion 14 is mounted on the inner surface thereof to a hub 22 shown in FIG. A plurality of hub bolts 24 are respectively provided upright on the hub 22 corresponding to the plurality of hub bolt holes 18. The plurality of hub bolts 24 are connected to the plurality of hub bolt holes 18.
, And in this state, a plurality of hub nuts (not shown) are screwed into the plurality of hub bolts 24, whereby the wheels are integrally rotatably fixed to the hub 22.

As shown in FIG. 1, a drive shaft 30 is integrally and rotatably attached to the hub 22. The drive shaft 30 is connected to the engine via a differential and a transmission (not shown). The hub 22 has a ball bearing 34.
, The steering knuckle 35 is held so as to be relatively rotatable. A lower end of a shock absorber 36, which is a component of the suspension, is fixed to the steering knuckle 35, and an upper end thereof is fixed to a body of the vehicle via an upper support (not shown). A knuckle arm (not shown) extends from the steering knuckle 35, and a tie rod 4 is attached to the knuckle arm.
0 is rotatably connected. Further, the steering knuckle 35 is rotatably connected to a lower arm 42 as another component of the suspension via a ball joint 44. Further, a brake rotor 46 of a disc brake 45 is attached to the drive shaft 30 so as to be integrally rotatable.

As shown in FIG. 2, the wheel according to the present embodiment is provided with a curvature on both the surface of the disk portion 10 and the surface of the rim portion 12 thereof. The disk portion 10 has curvature imparting portions 50 and 52 formed on the inner surface and the outer surface thereof, respectively.
In addition, the curvature imparting portions 5 are respectively provided on the inner surface and the outer surface thereof.
4, 56 are formed. The curvature imparting portions 50 and 52 of the disk portion 10 are provided with a curvature such that each portion of the disk portion 10 in the circumferential direction is curved outwardly of the vehicle body. On the other hand, the curvature imparting portions 54 of the rim portion 12,
The curvature is given to 56 so that each part in the circumferential direction of the rim portion 12 is curved in a direction toward the rotation center of the wheel. When the curvature is given to the surface of the wheel in this manner, the primary natural frequency of the wheel is changed by the vibration transmission system, that is, each of the tire, suspension, drive shaft 30, differential, transmission, and engine. It is different from any of the primary natural frequencies.

When the tire vibrates due to unevenness of the road surface, the vibration is transmitted to the wheel. In addition to the engine vibration, the transmission,
It is transmitted via a differential and drive shaft 30. Further, the vibration of the wheel is transmitted to the body via the suspension. However, in the present embodiment, as described above, since the primary natural frequency of the wheel is different from the primary natural frequency of the vibration transmission system, the tire vibration is amplified and transmitted to the body. The noise in the vehicle is reduced as a result. According to experiments performed by the inventor, it has been confirmed that this wheel reduces in-vehicle noise in a frequency range of about 100 to about 500 Hz.

FIG. 4 conceptually shows a conventional wheel. This wheel is formed by joining a rim part 100 and a disk part 102, and the disk part 102
The steering knuckle 104 has a hub mounted thereon.
06 is attached. FIG. 5 conceptually shows, by broken lines, how the conventional wheel deforms in its primary natural vibration mode. Thus, in this conventional wheel, in the primary natural vibration mode of the disc 102, the joint of the rim 100 is a joint,
The steering portion of the steering knuckle 104 is vibrated so as to be a belly. If the hub is considered as a vibration source for the wheel, the position of the antinode of the primary natural vibration mode is close to the vibration source. Therefore, the disk unit 102
, The vibration amplitude was large, and the vehicle interior noise caused by the vibration of the wheels tended to increase.

On the other hand, in the present embodiment, as shown in FIG. 6, in the primary natural vibration mode of the disk portion 10, the joint portion of the rim portion 12 and the mounting portion of the hub 22 are respectively provided. Vibrated to be a node. If the hub 22 is considered as a vibration source for the wheel, the position of the node in the first natural vibration mode is made closer to the vibration source. Therefore, according to the present embodiment, the vibration amplitude of the disk unit 10 is reduced as compared with the conventional wheel described above, and as a result, the in-vehicle noise caused by the vibration of the wheels is reduced.
Furthermore, in the present embodiment, the curvature is also given to the rim portion 12, so that the vibration amplitude in the primary natural vibration mode is also reduced.

As mentioned above, one embodiment of the present invention has been described in detail with reference to the drawings. However, this is an exemplification, and the present invention provides the above-mentioned [Problems to be solved by the invention, means for solving the problem, and effects of the invention] And various modifications and improvements based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a front view showing a tire wheel according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a partial cross-sectional front view showing a portion of the automobile to which the tire wheel is mounted.

FIG. 4 is a side sectional view conceptually showing a conventional tire wheel.

FIG. 5 is a side view for explaining a primary natural vibration mode of the conventional tire wheel.

FIG. 6 is a side view for explaining a primary natural vibration mode of the tire wheel according to the embodiment.

[Explanation of symbols]

 10 disk section 12 rim section 50, 52, 54, 56 curvature imparting section

Claims (2)

[Claims] Claims: 1. A wheel constituting a wheel of an automobile together with the tire when the tire is mounted, wherein the wheel has a natural frequency different from that of a vibration transmission system for transmitting vibration to the wheel. Wheels for tires. 2. The tire wheel according to claim 1, wherein the natural frequency is made higher than the natural frequency of the vibration transmission system by giving a curvature to the surface of the wheel.