Wheel structure

#The invention relates in general to an improvement in a wheel structure for vehicles. More specifically, the invention relates to reducing noise caused by a wheel structure.

#FIG. 10 is a schematic diagram of a wheel which has heretofore been used, and which will be described with reference to FIG. 10. It has heretofore been known that columnar resonance occurring in a closed space defined by a tire 1 and a wheel 10 causes the deterioration of a load noise during vehicle travel. To be more exact, the columnar resonance is a resonance sound occurring when random vibration inputted from a road surface into the tire vibrates the air in the closed space 5 to cause a resonance phenomenon to occur in the vicinity of a columnar resonance frequency of the closed space 5.

#This columnar frequency is generally determined on the basis of an equation:

#Preferred embodiments of the invention will be described in detail on the basis of the following figures, wherein:

#FIG. 1 is a perspective view of wheel in accordance with a first embodiment of the invention.

#FIG. 2 is a schematic side view illustrating the operation of the wheel in FIG. 1;

#Different embodiments of the invention will now be described with reference to the drawings. FIGS. 1-5 show a first embodiment of the wheel structure for vehicles according to the present invention, FIG. 6 a second embodiment of the wheel structure for vehicles according to the present invention, FIG. 7 a third embodiment of the wheel structure for vehicles according to the present invention, FIG. 8 a fourth embodiment of the wheel structure for vehicles according to the present invention; and FIG. 9 another embodiment of the wheel structure for vehicles according to the present invention. Referring to FIGS. 1-9, structural parts identical with those of the above-described related prior art wheel structure will be designated by the same reference numerals.

#As shown in FIG. 1, four side elevationally arcuate bulkheads (projections) 15 each of which has a length of about ⅛ of that of the whole of an outer circumferenctial surface 3 of a rim portion 6 of a wheel 10 of a vehicle are arranged at regular intervals on the same outer circumferential surface 3, whereby a cross-sectional shape of a closed space 5 enclosed with and defined by a tire 1 and a wheel 10, which constitute a wheel unit 12, is varied in the circumferential direction thereof as shown in FIG. 3.

#The first embodiment of the wheel structure for vehicles according to the present invention is formed as described above. Accordingly, a columnar resonance frequency in the closed space in a condition A in which a bulkhead 15 does not exist as shown in FIG. 2 on the part of the outer circumferential surface 3 of the rim portion 6 which is opposed to a ground contacting surface 17 of the tire and that of the closed space in a condition B attained after the wheel unit in the condition A makes a substantially ⅛ turn to have a bulkhead 15 positioned on the above-mentioned part of the outer circumferential surface 3 are different. Referring to FIGS. 2 and 3, a reference numeral 20 denotes a radially intermediate portion of the closed space 5.