This application is based upon and claims priority from the Japanese Patent Application No. 2018-071164, filed on Apr. 2, 2018, the entire contents of which are incorporated herein by reference.
The present invention relates to a vehicle wheel.
As an example of conventional art, there is known a Helmholtz resonator which is disposed on an outer circumferential surface of a well part in a wheel, and both edges of which projecting in the wheel width direction are engaged with a circumferential groove of a rim (for example, see Patent document 1: Japanese Unexamined Patent Application Publication No. 2012-45971).
The Helmholtz resonator allows the both edges thereof to be elastically deformed when pressed against the outer circumferential surface of the well part, thereby being easily fitted into the circumferential groove of the rim. Consequently, the Helmholtz resonator can be easily mounted on the wheel.
However, the conventional wheel with the Helmholtz resonator (for example, see Patent document 1) requires cutting and forming the circumferential groove for mounting the resonator on the rim. For this reason, the wheel has posed a problem in that a manufacturing process thereof becomes complicated to increase a manufacturing cost.
In order to solve the problem, for example, a resonator mounting structure is conceived in which the Helmholtz resonator is fixed to the wheel with an adhesive material.
In the Helmholtz resonator mounted on the wheel, however, an extremely large centrifugal force is generated by high-speed rotation of the tire during vehicle traveling. For this reason, a resonator mounting structure has been demanded, which is adapted to more certainly prevent the Helmholtz resonator from falling off the wheel due to the centrifugal force.
The present invention has therefore been made in view of the above problems, and an object of the invention is to provide a vehicle wheel capable of more certainly preventing a Helmholtz resonator from falling off a wheel due to a centrifugal force.
In order to attain the above object, according to an aspect of the present invention, a vehicle wheel reflecting one aspect of the present invention includes: a Helmholtz resonator adhered on a wheel; and a stopper supported on the wheel and configured to limit displacement of the Helmholtz resonator toward outside in a wheel radial direction.
According to the vehicle wheel reflecting one aspect of the present invention, the Helmholtz resonator can be more certainly prevented from falling off the wheel due to a centrifugal force.
The features and advantages provided by one or more embodiments of the invention will become apparent from the detailed description given below and appended drawings which are given only by way of illustration, and thus are not intended as a definition of the limits of the present invention.
Hereinafter, vehicle wheels according to embodiments of the present invention will be described in detail with reference to the drawings as appropriate. Note that in
In the description below, overall structure of a vehicle wheel will be first described, and then description will be given of a sub-air chamber member serving as a Helmholtz resonator and of a mounting structure of the sub-air chamber member on a rim by an adhesive material.
As shown in
Moreover, the vehicle wheel 1 is provided with a stopper 41 as described in detail later.
In
The rim 11 includes a well part 11c which is concave inward (toward a rotation center) in the wheel radial direction between bead seats (not shown) formed on both end parts of the rim 11 in the wheel width direction Y. An outer circumferential surface 11d of the well part 11c is defined by a bottom face of the concave part and has substantially the same diameter on the wheel shaft throughout the wheel width direction Y.
The rim 11 in the present embodiment is provided with a vertical wall 15.
Incidentally, the vertical wall 15 in the present embodiment is formed at the one side (inner side) in the wheel width direction Y and in a rising part 17 that erects from the outer circumferential surface 11d of the well part 11c toward a rim flange side.
Although the vertical wall 15 annularly extends in the wheel circumferential direction X to forma side face 14 such that an angle between the side face 14 and the outer circumferential surface 11d (see
Next, the sub-air chamber member 10 will be described.
As shown in
The main body 13 is curved in a longitudinal direction thereof. In other words, the main body 13 is configured to follow the wheel circumferential direction X when the sub-air chamber member 10 is mounted on the outer circumferential surface 11d (see
The main body 13 has a hollow part inside. The hollow part (not shown) forms a sub-air chamber SC (see
As shown in
More specifically, the main body 13 has configuration in which a bottom part 25b (bottom plate) that is disposed along the outer circumferential surface 11d of the well part 11c, a side part 25c (side plate) that is disposed along the side face 14 of the vertical wall 15, and an upper part 25a (upper plate) that forms a hypotenuse between the bottom part 25b and the side part 25c, are mutually connected so as to form a right triangle.
That is, the side part 25c and the bottom part 25b forma right angle by the angle of inclusion between them. The upper part 25a extends to form an ascending slope from the bottom part 25b side toward the side part 25c.
Moreover, between the outer circumferential surface 11d of the well part 11c and the bottom part 25b, and between the side face 14 of the vertical wall 15 and the side part 25c, clearances of predetermined gaps are formed so that an adhesive material 21 having film thicknesses as described later can be interposed.
Thus, the upper part 25a, the bottom part 25b and the side part 25c are formed to surround the sub-air chamber SC inside the main body 13.
Next, the tubular body 18 (see
The sub-air chamber member 10 in the present embodiment is formed, as described above, into a symmetric shape in the wheel circumferential direction X with respect to the partition wall 16. Accordingly, although only one tubular body 18 is shown in
As shown in
The communication hole 18a allows the sub-air chamber SC (see
The sub-air chamber member 10 in the present embodiment is a blow molded product using a synthetic resin such as polyamide resin as described above. Note that the above synthetic resin is not specifically limited, but polyamide resin containing polyamide MXD6 (Registered trade mark) as a base resin, and nylon 6 are especially preferably used.
Next, the stopper 41 (see
The stopper 41 in the present embodiment is composed of a bent plate-like body consisting of resin, metal, or resin-fiber composite material (e.g., carbon-fiber reinforced plastic (CFRP)).
As shown in
Note that, although only one stopper 41 is shown in
As shown in
The stopper main body 41a has a plurality of through-holes 41d (four through-holes in the present embodiment) and is formed of a plate-like body elongated in the wheel width direction Y. The through-holes 41d make it possible to achieve weight saving of the stopper 41.
As shown in
More specifically, the stopper main body 41a is inclined with a gap G so as to be nearly parallel to the upper part 25a (upper plate) composing the main body 13 of the sub-air chamber member 10.
As shown in
The folded section 41b allows displacement in the circumferential direction of the sub-air chamber member 10 (Helmholtz resonator) to be restricted.
As shown in
Next, description will be given of a mounting structure of the sub-air chamber member 10 (see
As shown in
Examples of the adhesive material 21 include thermoplastic resin-based adhesive such as ethylene-vinyl acetate resin; thermosetting resin-based adhesive such as epoxy resin, polyurethane resin, acrylic resin and polyamide resin; and elastomer-based adhesive such as synthetic rubber and thermoplastic elastomer, but the adhesive material is not limited to these examples.
Incidentally, the form of hardening of the adhesive material 21 is not specifically limited, but chemical reaction hardening is especially preferably used.
The adhesive material 21 can be coated on either the sub-air chamber member 10 or the rim 11. Moreover, the adhesive material 21 can also be coated on both of the sub-air chamber member 10 and the rim 11.
Examples of coating method for the adhesive material 21 include bar coating method, roll coating method, spray coating method, brush coating method, and hot-melt coating method, but the coating method is not limited to these examples.
Next, film thicknesses of the adhesive material 21 will be described.
As shown in
As shown in
Controlling the film thicknesses T1, T2 of the adhesive material 21 in this way allows fixing strength of the sub-air chamber member 10 to the rim 11 to be extremely enhanced.
This will be described below. A centrifugal force F (see
In contrast, the adhesive material 21 has higher shear strength as it becomes thinner and has higher peel strength as it becomes thicker.
On the other hand, in the vehicle wheel 1 according to the present embodiment as shown in
On the contrary, the centrifugal force acts most largely on apart of the main body 13 adjacent to the vertical wall 15, to which mass of materials forming the side part 25c (side plate) is added.
The part of the main body 13 adjacent to the vertical wall 15, on which the centrifugal force acts most largely, satisfies the relation of “film thickness T1<film thickness T2”, thus allowing both “shear strength” of the adhesive material 21 on the side face 14 and “peel strength” of the adhesive material 21 on the outer circumferential surface 11d to be enhanced. This allows the fixing strength of the sub-air chamber member 10 to the rim 11 to be extremely enhanced.
Moreover, more preferable setting of film thicknesses of the adhesive material 21 satisfying the relation of “film thickness T1<film thickness T2” is as follows.
As shown in
Moreover, the peel strength [N/mm] gradually increases and then reaches a saturation point (see the film thickness T2) as the film thickness becomes increased from 0 [μm]. That is, the peel strength [N/mm] becomes the maximum at the saturation point (see the film thickness T2).
Accordingly, the sub-air chamber member 10 (see
Incidentally, the relation of the shear strength [N/mm2], the peel strength [N/mm], and the film thickness [μm] of the adhesive material 21 shown in
Moreover, the applied surface of the adhesive material 21 (see
In particular, it is still more preferable that the applied surface of the adhesive material 21 in which a shearing force is generated during action of the centrifugal force F (see
As shown in
The laser-etched surface 22 is composed of an etched groove 22a and a ridge part 22b.
The laser-etched surface 22 in the present embodiment is formed on the side face 14, e.g., when a YAG laser is scanned in one direction on the side face 14, and extends with a predetermined groove depth from the front side of the page space in
Moreover, the ridge part 22b in the present embodiment is formed with protrusion of a predetermined height at both sides in a width direction of the etched groove 22a, respectively, and extends in an extending direction of the etched groove 22a.
The laser-etched surface 22 is formed, e.g., by allowing a YAG laser to be scanned with a predetermined width of hatching on the side face 14. More specifically, the YAG laser causes the etched groove 22a to be formed with a predetermined depth and substance eluted by laser irradiation deposits and hardens at both sides of the etched groove 22a, thereby allowing the ridge part 22b to be formed with a predetermined height.
Note that, although the extending direction of the etched groove 22a and the ridge part 22b in the present embodiment is set to the wheel circumferential direction X, it is not limited to the wheel circumferential direction X.
The present embodiment allows the laser-etched surface 22 to be set on the side face 14, thereby allowing the adhesive material 21 to be filled in the etched groove 22a and between adjacent ridge parts 22b. Moreover, on the laser-etched surface 22 although not shown, an end part of the ridge part 22b is displaced in a groove width direction of the etched groove 22a to allow a side face of the ridge part 22b to overhang, or the end parts of the adjacent ridge parts 22b are connected to each other on the etched groove 22a to partially form an arch.
This allows anchor structure of the adhesive material 21 to be constructed on the laser-etched surface 22 by the adhesive material 21 deeply entering the etched groove 22a and the adhesive material 21 engaged with the overhanging portion and the arch.
Accordingly, the fixing strength of the sub-air chamber member 10 to the rim 11 becomes enhanced.
Moreover, the laser-etched surface 22 makes it possible to further improve the fixing strength of the sub-air chamber member 10 to the rim 11 through enhancing effects of wettability accompanied by surface free energy structure of solid parts of metal (see Young's equation of angle of contact).
Note that it goes without saying that the laser-etched surface 22 can also be formed on the side part 25c of the main body 13 as described above.
As shown in
The adhesive material 21 located between the vertical wall 15 and the side part 25c allows an upper part thereof to spread above the corner radius section 13a to cover the corner radius section 13a from above.
The adhesive material 21 covering the corner radius section 13a from above makes it possible to further enhance the fixing strength of the sub-air chamber member 10 to the rim 11.
Next, description will be given of a mounting structure of the stopper 41 (see
As shown in
Of a pair of supporting parts 41c, one supporting part 41c is connected via the adhesive material 21 to a flat surface of the rim 11, which is adjacent to an upper end of the vertical wall 15 and extends from the upper end of the vertical wall 15 toward the rim flange side.
Moreover, the other supporting part 41c is connected via the adhesive material 21 to the outer circumferential surface 11d of the well part 11c.
As for the adhesive material 21, the same adhesive material as that used in the above adhesion of the sub-air chamber member 10 to the rim 11 can be used. The adhesive material 21 can be coated on either the stopper 41 or the rim 11. Moreover, the adhesive material 21 can also be coated on both of the stopper 41 and the rim 11.
Examples of coating method for the adhesive material 21 include bar coating method, roll coating method, spray coating method, brush coating method, and hot-melt coating method, but the coating method is not limited to these examples.
Shear adhesion (adhesive strength) of the stopper 41 to the rim 11 can be defined by a ratio of mass of the stopper 41 to an adhesive area of the stopper 41 to the rim 11. Moreover, from the point of view of design standard for safety, setting of the ratio of the mass of the stopper 41 to the adhesive area is carried out so as to allow the sub-air chamber member 10 to certainly fall off the rim 11 at a lower rotational speed than a rotational speed at which the stopper 41 falls off the rim 11. Compared with the ratio of a total of set adhesive strength (the shear strength and the peel strength) to unit mass of the sub-air chamber member 10, the corresponding ratio in the stopper 41 is set sufficiently high.
The stopper 41 is adapted to limit displacement of the sub-air chamber member 10 (Helmholtz resonator) toward outside in the wheel radial direction Z and in the wheel circumferential direction X, as described below.
Next, description will be given of operation and effects of the vehicle wheel 1 according to the present embodiment.
The vehicle wheel 1 according to the present embodiment allows the sub-air chamber member 10 to be mounted on the rim 11 with the adhesive material 21.
The vehicle wheel 1 thus configured differs from the conventional vehicle wheel (for example, see Patent document 1) and has no need to cut and form a circumferential groove for mounting the sub-air chamber member 10 on the rim 11. Accordingly, the vehicle wheel 1 makes it possible to simplify a manufacturing process to reduce a manufacturing cost as compared to the conventional art.
Moreover, the stopper 41 in the vehicle wheel 1 according to the present embodiment is disposed on the outside of the sub-air chamber member 10 in the wheel radial direction Z to be adhered on the wheel (the rim 11) separately from the sub-air chamber member 10.
The vehicle wheel 1 thus configured allows a centrifugal force generated in the sub-air chamber member 10 per se to be not applied directly to the stopper 41. Accordingly, the sub-air chamber member 10 together with the stopper 41 is prevented from falling off the rim 11 toward an inner circumferential wall side of the tire (not shown). That is, even if the adhesive layer (adhesive material 21) between the sub-air chamber member 10 and the outer circumferential surface 11d of the well part 11c is broken during rotation of the wheel, the sub-air chamber member 10 is caught by the stopper 41 to allow displacement thereof toward outside in the wheel radial direction Z and in the wheel circumferential direction X to be limited. The sub-air chamber member 10 caught by the stopper 41 is held in the well part 11c.
Moreover, in the vehicle wheel 1, the gap G is formed between the sub-air chamber member 10 and the stopper 41.
When the adhesive layer (adhesive material 21) between the sub-air chamber member 10 and the outer circumferential surface 11d of the well part 11c is broken, the vehicle wheel 1 configured as described above allows the sub-air chamber member 10 displaced in the centrifugal direction to come into contact with the stopper 41, thereby generating an abnormal noise.
This makes it possible for a user to perceive from the abnormal noise that the sub-air chamber member 10 is caught by the stopper 41 to be held. That is, the user can recognize the abnormal noise as predictable phenomenon until the sub-air chamber member 10 completely falls off the rim 11 toward the inner circumferential wall side of the tire (not shown). Therefore, the user can prepare for repair and restoration of the sub-air chamber member 10 through predictability of the vehicle wheel 1.
Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be put into practice in various forms.
As shown in
The metal plate 24 (the smoothing member for adhesion) is formed of the same material as that of the rim 11, but the material is not limited to this example.
The metal plate 24 allows the opposed surface 24a opposed to the outer circumferential surface 11d to have a flat surface for adhesion of the adhesive material 21. As for the flat surface, the surface of the metal plate 24 is treated, e.g., by electrolytic polishing or buffing, so as to have the degree of flatness of 1 μm or less.
Moreover, the opposed surface 24b of the metal plate 24 opposed to the side face 14 is obtained by performing flattening treatment described above, followed by performing laser-etching (see the laser-etched surface 22 in
The sub-air chamber member 10 thus configured can be obtained by insert molding in which the metal plate 24 is arranged in a metal mold beforehand.
The vehicle wheel 1 (see
Moreover, the vehicle wheel 1 makes it possible to further enhance rigidity of the main body 13 of the sub-air chamber member 10, through reinforcing effect by the metal plate 24.
Furthermore, the vehicle wheel 1 allows the opposed surface 24b of the metal plate 24 opposed to the side face 14 to be formed of the laser-etched surface 22, thus allowing the fixing strength of the sub-air chamber member 10 to the rim 11 to be further increased.
As shown in
The stopper 41 forms an annular body that extends in the wheel circumferential direction X on the outer circumferential surface 11d of the well part 11c.
Moreover, the main body 13 is adhered on the outer circumferential surface 11d of the well part 11c with an adhesive material (not shown).
Note that, although the second modification assumes that the stopper 41 is in contact with, but not adhered on, the outer circumferential surface 11d of the well part 11c, the present invention may adopt configuration such that the stopper 41 is adhered on the outer circumferential surface 11d.
According to the vehicle wheel 1 thus configured, even if an adhesive layer (not shown) between the sub-air chamber member 10 and the outer circumferential surface 11d of the well part 11c is broken during rotation of the wheel, displacement of the sub-air chamber member 10 toward outside in the wheel radial direction Z and in the wheel circumferential direction X is limited by the stopper 41. The sub-air chamber member 10 is held by the stopper 41 in the well part 11c.
As shown in
Moreover, above both edges in the wheel width direction Y of the sub-air chamber member 10 (on the outer side in the wheel radial direction Z), the stoppers 41, 41 are disposed each protruding in the form of an eave from the rim 11 located at the outer side in the wheel width direction Y of the well part 11c. That is, the gap G is formed between the sub-air chamber member 10 and the stopper 41.
The stopper 41 assumes configuration such that a plate-like body extending in the wheel circumferential direction X (see
According to the vehicle wheel 1 thus configured, even if the adhesive layer (adhesive material 21) between the sub-air chamber member 10 and the outer circumferential surface 11d of the well part 11c is broken during rotation of the wheel, displacement of the sub-air chamber member 10 toward outside in the wheel radial direction Z and in the wheel circumferential direction X is limited by the stopper 41. The sub-air chamber member 10 is held by the stopper 41.
Moreover, when the adhesive material 21 is broken, the vehicle wheel 1 allows the sub-air chamber member 10 displaced in the centrifugal direction to come into contact with the stopper 41, thereby generating an abnormal noise.
This makes it possible for the user to recognize the abnormal noise as predictable phenomenon until the sub-air chamber member 10 completely falls off the rim 11 toward the inner circumferential wall side of the tire (not shown).
As shown in
According to the vehicle wheel 1 according to the fourth modification, the same operation and effects as those in the vehicle wheel 1 according to the third modification can be produced, and formation of the stopper 41 can be simplified.
Moreover, although the embodiment and modifications described above assumes that the angle between the well part 11c and the vertical wall 15 is set to 90 degrees, the angle can also be set to an angle exceeding 90 degrees.
Although embodiments of the present invention have been described and illustrated in detail, the disclosed embodiments are made for purposes of illustration and example only and not limitation. The scope of the present invention should be interpreted by terms of the appended claims.
1: Vehicle wheel; 10: Sub-air chamber member; 11: Rim; 11c: Well part; 11d: Outer circumferential surface; 13: Main body; 13a: Corner radius section; 14: Side face; 15: Vertical wall; 18: Tubular body; 18a: Communication hole; 21: Adhesive material; 22: Laser-etched surface; 22a: Etched groove; 22b: Ridge part; 24: Metal plate; 25a: Upper part; 25b: Bottom part; 25c: Side part; 41: Stopper; 41a: Stopper main body; 41b: Folded section; 41c: Supporting part; 41d: Through-hole; F: Centrifugal force; G: Gap; SC: Sub-air chamber; T1: Thickness of adhesive material; T2: Thickness of adhesive material; X: Wheel circumferential direction; Y: Wheel width direction; Z: Wheel radial direction
Number | Date | Country | Kind |
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2018-071164 | Apr 2018 | JP | national |