Abstract: A grille unit has a frame and a vane pivotally connected to the frame via opposing first and second shafts. The frame has first and second holes snugly receiving the first and second shafts respectively. The first shaft has a peripheral surface, the diameter of which continuously varies along the axis thereof. The second shaft has a similar peripheral surface. The varying-diameter surfaces of the first and second shafts face in opposite directions. The frame has a first inner surface which conforms to the varying-diameter surface of the first shaft to engage the latter. The frame has a second inner surface which conforms to the varying-diameter surface of the second shaft to engage the latter. A method of manufacturing the grille unit includes the steps of forming the frame from plastic, and assemblying a mold with the frame positioned within the mold.

Abstract: An instrument panel concealing plate is integrally formed with an instrument panel about a steering column for concealing the inside of the instrument panel so as not to be visible through the instrument panel and a steering column cover. According to the invention the concealing plate is formed with a breaking portion consisting of a series of slots or grooves formed in the concealing plate, so that the plate is adapted to be easily broken off when it is subjected to an impact by a steering column cover in collision of a vehicle, thereby absorbing the impact caused by a collision of a bosom of a driver against a steering wheel and preventing sharp edges of broken parts of the steering column cover caused by the breaking off of the cover itself, which would otherwise injure the driver.