Abstract: A vehicle wheel according to the present invention includes a hollow-state hollow portion and a solid-state non-hollow portion inside an outboard bead seat in a radial direction, which are provided in series in a circumferential direction of the wheel, the non-hollow portion having a cross section with a larger area than a hole cross section of a valve hole and having the valve hole formed therein. This structure prevents a sealing structure for ensuring hermetic performance from being complicated as compared to a wheel having the valve hole in the hollow portion, thus simplifying a mounting structure of an air valve. A method for manufacturing such a vehicle wheel allows formation of the valve hole in the non-hollow portion. Machining dust generated through a cutting process can thus be prevented from entering the hollow portion and remaining therein.

Abstract: A wheel for an automobile is configured in such a manner that the wheel disc comprises an outer peripheral ring section having protrusions and recesses, the outer peripheral ring section being formed by continuously and alternately forming circular arc-shaped contact sections and contactless protrusion sections along the circumferential direction of the wheel, the circular arc-shaped contact sections being in contact with and welded to the bent peripheral section of the wheel rim, the contactless protrusion sections protruding further toward the front side than the circular arc-shaped contact sections and separating from the bent peripheral section. Welded sections at which the circular arc-shaped contact sections and the bent peripheral sections are welded together are intermittently arranged in the circumferential direction of the wheel.

Abstract: An automobile wheel includes: a wheel rim 2 including a circumferential positioning fitting groove 32 formed circumferentially around the center axis of the wheel rim 2 in the front surface of a circumferential bent portion 31 at which a front bead seat portion 13 and a front rim flange portion 11 are formed continuously with each other; and a wheel disc 3 including a circumferential insertion edge 36 formed circumferentially around the center axis of the wheel disc 3 on the back surface of an outer peripheral edge portion 24. The wheel rim 2 and the wheel disc 3 are welded to each other for integration with the circumferential insertion edge 36 fitted in the circumferential positioning fitting groove 32. The respective center axes of the wheel rim 2 and the wheel disc 3 are aligned with each other with high precision, achieving an advantageous effect that vibration that occurs while an automobile is running is suppressed to improve the operation stability and achieve high durability.

Abstract: A hat portion of a wheel disk includes a hat inner inclined circumferential portion and a hat outer inclined circumferential portion. At least one of the hat inner inclined circumferential portion and the hat outer inclined circumferential portion includes: a plurality of curved protruding circumferential portions that protrude toward a surface side into a curved shape; and at least one curved recessed circumferential portion that is provided between the adjacent curved protruding circumferential portions and that is recessed toward a back side into a curved shape. The hat portion of this construction provides a significant effect in improving stiffness because of the shapes of the curved protruding circumferential portions and the curved recessed circumferential portion. Consequently, an automobile wheel has improved overall stiffness and strength. Therefore, a car on which the automobile wheel is mounted can provide increased driving stability.

Abstract: A base coat coating composition which is able to suppress cracking of a metal thin film, even when a tough top coat layer capable of satisfactorily protecting the metal thin film is formed on the metal thin film, and even when a heat resistance test is performed, as well as a composite film and a method for producing the composite film. Specifically, a base coat coating composition used for undercoating a metal thin film formed on a metal substrate, and containing a coating film-forming component which contains at least 30% by mass of an epoxy (meth)acrylate having a cyclic structure and has an average molecular weight between crosslinks of 180 to 1,000, as well as a composite film having a base coat layer obtained from the base coat coating composition, and a method for producing the composite film.

Abstract: An automobile wheel includes first bottom portions provided inward in a radial direction of a front side bead seat portion and a back side bead seat portion between the front side bead seat portion and back side bead seat portion and second bottom portions provided inward in the radial direction of the first bottom portions. The first bottom portions and second bottom portions are alternately provided in a circumferential direction. This configuration increases difference in area between area of a cross section in the radial direction of a tire-internal space in sections where the first bottom portions are provided and area of a cross section in the radial direction in sections where the second bottom portions are provided and thus allows improvement in an effect of reducing cavity resonant noise.

Abstract: An exploration operation, in which the transmission/reception position, at which ultrasonic waves are transmitted and received, is changed by a specified pitch distance, is performed for each of a plurality of incident angles. A nonlinear image in which echo signals acquired from harmonic waves of reflected waves are presented is generated for each incident angle. Each nonlinear image is converted into a frame conversion image in accordance with the cross-sectional shape of an exploration-target area. A signal intensity threshold for removing echo signals resulting from an orientation defect is determined in advance. Frame conversion images formed by only echo signals 41a whose signal intensity is the signal intensity threshold or more are overlapped to generate a nonlinear exploration image 35. Exploration of a welded portion 23 stably provides a nonlinear exploration image 35 in which the shape of an interface 25 of the welded portion 23 is shown accurately and clearly.

Abstract: This invention provides a fuel tank of a simple structure without any special device but having space of a predetermined ratio after the fuel tank has been filled with liquefied fuel. The fuel tank is of a form in which a number of cylindrical or spherical containers are arranged in parallel and are coupled together in a manner that the cylindrical or spherical containers neighboring each other share partitioning walls, respectively. Each of the partitioning walls has a passage through which the neighboring cylindrical or spherical containers are communicated with each other, and the upper ends of the passages are formed leaving partly the inner partitioning walls so that the liquid will not enter into the upper parts of the cylindrical or spherical containers.

Abstract: The present invention proposes an automotive wheel that can exhibit high strength and high durability. The automotive wheel includes a wheel disc in which a hat section is provided outside a hub mounting section, and a hat inner inclined surrounding section of the hat section includes an inner convex surrounding section protruding to a surface side in a curved shape, and an inner lower concave surrounding section continuously formed with an inner peripheral edge of the inner convex surrounding section, continuously formed with an outer peripheral edge of a hub surface rounded section, and protruding to the back side in the curved shape. The automotive wheel according to the present invention can reduce the stress concentration on the hub surface rounded section which is produced by the lateral force applied during the traveling of the automobile, and therefore high strength and high durability can be provided.

Abstract: In an automotive wheel, a well recessed portion that is recessed in the back-side direction along a well bottom portion forming a well of a wheel rim is formed at a portion of a back-side well wall portion of the well opposite a valve hole. Thus, vibration generated by the centrifugal force of an air valve with a pneumatic pressure detection device while an automobile is running can be suppressed by the effect due to the shape of the well recessed portion, and the operation stability, the riding comfort, and so forth of the automobile can be improved. In another automotive wheel, a well recessed portion that is recessed in the surface-side direction along a well bottom portion forming a well of a wheel rim is formed at a portion of a surface-side well wall portion forming the well at which a valve hole is formed such that a surface-side portion of a pneumatic pressure detection device of an air valve with a pneumatic pressure detection device is fitted in the well recessed portion.

Abstract: An automotive wheel that can prevent deformation of a back side opening edge of a wheel rim in a radial direction and reduce the weight of the wheel rim is proposed. Because the automotive wheel has a structure in which an annular rib section formed in a stepped manner at each of the inside and the outside and having a thinner wall thickness than the other part of a ledge section is circumferentially formed in the ledge section of the wheel rim, an effect of preventing the deformation of a back side opening edge of the wheel rim in a radial direction is improved by virtue of a shaping effect of the annular rib section, and a weight reduction effect can be provided in connection with the thinner wall thickness of the annular rib section.

Abstract: Producing a metal composite material by mixing hydrated ceramic particles, having water of crystallization that is bound within fine pores which have an average pore diameter of 1 nm or more and 80 nm or less, with a reinforcing material, the resulting mixture being sintered to form a preform which is then impregnated with a melt of an aluminum alloy and subjected to surface polishing. The ceramic particles, from which water of crystallization has been removed while the average pore diameter of the pores thereof is maintained, are dispersed uniformly, it is possible to obtain the metal composite material in which the ceramic particles that have fine pores are exposed on surfaces evenly in a stable manner by surface polishing that is conducted after the melt impregnation. The metal composite material can permit infiltration of a lubricating oil into the fine pores.

Abstract: In an automobile wheel, a surface-side flange is provided on an outer circumferential edge of a wheel disk. The surface-side flange includes: a surface-side annular circumferential portion on an aesthetic surface; and a back-side annular circumferential portion that is formed continuously with, and on the back side of, the surface-side annular circumferential portion and that is thinner than the surface-side annular circumferential portion. An inner circumferential end of the back-side annular circumferential portion of the surface-side flange and an opening end of a surface-side bead seat of a wheel rim are welded together all along their circumferences. The automobile wheel allows the back-side annular circumferential portion of the surface-side flange to bear a stress that acts on a weld area. This relaxes the stress concentration on the weld area.

Abstract: An automobile wheel having a wheel di.sk with improved stiffness and increased strength and driving stability. An imaginary inward angled line is tangential to an inner circumferential surface of an inward recessed circumferential portion of a hat portion and tangential to an inner circumferential surface of a hub surface rounded portion of a hub mounting portion. An imaginary outward angled line is tangential to an inner circumferential surface of an outward recessed circumferential portion of the hat portion and runs through an intersection point of a disk flange and an imaginary bottom line. The imaginary bottom line extends along a back side surface of the hub mounting portion. The imaginary inward and outward angled lines satisfy a ratio of an imaginary outward angle to an imaginary inward angle of equal to or greater than 0.8 to equal to or smaller than 1.25 with respect to the imaginary bottom line.

Abstract: In an automobile wheel, a disc flange of a wheel disc includes bent surface-side edge portions each having an arcuate shape and arranged concentrically with each other, and the bent surface-side edge portions extend from the surface-side end edge of a fitted straight annular portion to be bent radially inward and are dented to a back side of the outer end portions of the lateral edge portions of spokes. The thus configured automobile wheel can exhibit high strength and rigidity against a radial load, a bending load, and a torsional load because of the shape of the bent surface-side edge portions, thereby suppressing deformation of the disc flange caused while an automobile is running. Thus, it is possible to mitigate a stress concentration on a joined portion between the wheel disc and a wheel rim.

Abstract: Because a front flange portion including an annular front peripheral portion and an annular back peripheral portion is formed along an outer peripheral edge portion of the wheel disc, and because a back surface portion and an opening end portion of a front bead seat portion of a wheel rim are welded to each other over the entire circumference of the wheel but the annular back peripheral portion and the wheel rim are not welded to each other, stress concentration on the front flange portion due to a load generated while the automobile is running can be mitigated. Therefore, an automobile wheel has high durability against a load generated while the automobile is running.

Abstract: A front flange portion formed at an outer peripheral edge portion of a wheel disc includes an annular front peripheral portion provided on a design surface side and an annular back peripheral portion folded backward from the annular front peripheral portion to extend radially inwardly and in surface contact with a back surface of the annular from peripheral portion, and the annular front peripheral portion and the annular back peripheral portion are integrally inclined to the surface side. Therefore, the front flange portion can mitigate stress concentration on the front flange portion due to a load generated while the automobile is running. In addition, the front flange portion has, because of its shape, high durability against a radially inward load generated by a contact with a curbstone or the like.

Abstract: An MMC cylinder liner comprises an inner tubular portion and an outer tubular portion. The inner tubular portion includes a metal matrix composite formed of a compact impregnated with an Al—Si alloy wherein the compact is made of a reinforcing material. The outer tubular portion is formed of the Al—Si alloy. The Si concentration of the Al—Si alloy impregnated into the compact of the inner tubular portion is different from the Si concentration of the Al—Si alloy of the outer tubular portion.

Abstract: An inner peripheral end portion of an annular back peripheral portion forming a front flange portion, an opening end portion of a front bead seat portion and a back surface portion of a wheel disc are joined to each other by a first welded portion and a second welded portion. Accordingly, it is possible to prevent the front flange portion from being repeatedly elastically deformed by loads generated while the automobile is running. In addition, it is possible to mitigate a stress concentration generated on the front flange portion and the first welded portion and the second welded portion. Thus, an automobile wheel can exhibit high durability.