JP2006044474A - Vehicular wheel having rotary auxiliary blade - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular wheel having rotary auxiliary blades capable of realizing the low fuel consumption by substantially reducing the rolling resistance of a tire in a wheel to be used for a car or a vehicle traveling at a normal speed. <P>SOLUTION: A plurality of rotary auxiliary blades 21-1 to 21-4 are provided on an outer face of a wheel 2 in a uniformly distributed manner in the tire circumferential direction. Each rotary auxiliary blade 21 comprises a rubber sheet 22 extending in the wheel radial direction, a fixed bar to support an edge on the inner side of the wheel radial direction of the rubber sheet 22 from a body side of the wheel, and a movable bar 24 connected to an edge on the outer side of the wheel radial direction. The movable bar 24 is connected to the fixed bar 23 via a coil-shaped spring 29, and guided in the wheel radial direction. As the movable bar is shifted from an upper end position to a lower end position when the vehicle travels, the rubber sheet 22 is drawn and extended by the gravity applied to the movable bar 24. The rotary auxiliary blades 21 receives air resistance in a vicinity of the lower end position than larger than that of the upper end position, and generates the rotary auxiliary force. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wheel used in an automobile or other vehicle that travels at a certain speed. In particular, the present invention relates to a wheel that can substantially reduce the rolling resistance of a tire or the like and achieve a reduction in fuel consumption.

  In recent years, social demands for reducing fuel consumption of automobiles have increased, and development of fuel efficiency reduction techniques for reducing rolling resistance of tires has been actively performed (for example, Patent Documents 1 to 3). The rolling resistance of a tire is a resistance caused by a tire made of rubber and a tire cord, which are viscoelastic bodies, rotating while being bent, and causes energy loss.

  In order to reduce this rolling resistance, it is necessary to suppress deformation of the entire tire that occurs during tire rotation, or to suppress energy loss due to repeated compression motion that occurs during road surface contact. For this purpose, studies have been made to optimize the shape and structure (profile) of the tire (Patent Document 3, etc.) or to optimize the rubber compounding composition. If the rolling resistance of the tire is reduced, it can greatly contribute to the reduction in fuel consumption of the vehicle particularly during steady speed traveling such as traveling on a highway.

  However, in these conventional methods, in order to improve rolling resistance, other performances such as wear resistance and wet performance are often deteriorated. For example, the method of reducing the blending amount of carbon black as a reinforcing agent may cause a decrease in wear resistance.

  On the other hand, it is also attempted to reduce rolling resistance by providing a vibration absorbing structure in the wheel (Patent Documents 1 and 2). A first disk provided with a rim and a second disk provided with a mounting portion for a vehicle are coupled via a rubber member. With such a structure, it is possible to suppress deformation / distortion when the tire rolls and to reduce hysteresis loss. However, in this case, a reduction in rolling resistance when traveling at a steady speed on a road surface with good pavement cannot be expected.

On the other hand, in an aircraft wheel, it has also been proposed to provide a wheel cap or the like with a rotational force generating wing for starting rotation of the wheel before landing in order to reduce wear during landing (Patent Document 4). However, the rotational force generating blades are not provided on the wheels for steady running of the vehicle, and do not realize low fuel consumption during running.
JP 2003-260902 A JP 2001-88506 A JP 2004-983838 A JP 2002-154485 A

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle wheel that can realize low fuel consumption during steady running without causing other performance degradation.

  The vehicle wheel according to the present invention is characterized in that a plurality of auxiliary rotation blades for converting a force received from an air flow when the vehicle is traveling into a rotational driving force are provided on the outer surface, and the wheel is evenly distributed in the circumferential direction of the wheel.

  According to a preferred aspect of the present invention, the rotation auxiliary wing is provided such that the area when viewed from the vehicle traveling direction increases as the vehicle moves from the upper end position to the lower end position during vehicle traveling. In this case, the generation of the rotational force that hinders the traveling of the vehicle due to the air resistance on the upper side of the vehicle rotation shaft is reduced as much as possible, and the generation of the rotational force that promotes the traveling of the vehicle is increased on the lower side of the vehicle rotation shaft. it can. Therefore, as a whole, an auxiliary rotational driving force can be easily generated, and fuel consumption or power can be reduced.

  According to another preferred aspect of the present invention, the rotation auxiliary wing has a convex shape toward the front surface in the rotation direction, and the rear surface in the rotation direction is a concave surface or a flat surface compared to the front surface.

  Rolling resistance can be substantially reduced, and fuel consumption or power can be reduced.

  Example 1 will be described with reference to FIGS. FIG. 1 is a schematic external perspective view showing the structure of the wheel 2 and its surroundings in the actual running state. FIG. 2 is a plan perspective view showing a state of the auxiliary rotation blades removed from the tire. FIG. 3 is a schematic vertical sectional view showing the state of FIG.

  As shown in FIGS. 1 to 3, the outer surface of the wheel cap 26 provided on the left and right of the wheel 2 is provided with a substantially flat plate-shaped rotation auxiliary wing 21 extending along the radial direction and the rotation axis direction of the wheel. . According to the illustrated example, the four rotation auxiliary wings 21-1 to 21-4 are provided on the outer surfaces of the left and right wheel caps 26 so as to be evenly distributed in the circumferential direction. Here, the wheel cap 26 is attached to the wheel body so as not to rotate by screwing or the like.

  In the example shown in FIGS. 2 to 3, each rotation auxiliary wing 21 supports one rectangular rubber sheet 22 extending in the wheel radial direction and a wheel radial inner edge of the rubber sheet 22 from the wheel cap 26. It consists of a fixed rod 23 and a movable rod 24 connected to the outer edge of the rubber sheet 22 in the wheel radial direction. The rubber sheet 22 has a cylindrical shape at both edges 22B in the tire radial direction, and a rubber sheet body 22A having an equal thickness is stretched between them. In addition, the fixed rod 23 and the movable rod 24 are one straight thin round bar in the illustrated example, and the core portions 23B and 24B that form the core of the cylindrical edge portion 22B of the rubber sheet 22 and the root portion 23A, 24A. The root 23A of the fixing rod 23 is connected to the wheel cap 26 by welding or screwing. On the other hand, the root portion 24A of the movable rod 24 has a short cylindrical shape with a diameter much larger than that of the core portion 24B, is formed of a material having a high density such as iron, and has a relatively large mass.

  A coiled spring 29 made of steel or the like is stretched between the root 24A of the movable rod 24 and the root 23A of the fixed rod 23. The root portion 24A of the movable rod 24 is guided in the wheel radial direction by a guide structure provided on the wheel cap 26, and the elastic force of the spring 29 and the rubber sheet 22, and the gravity and centrifugal force that the root portion 24A of the movable rod 24 receives. In response to these actions, the force moves sequentially to a position where these forces are balanced. When the auxiliary rotating wing 21 comes to the upper end position as shown in FIG. 3 while the vehicle is running, the gravity of the root 24A of the movable rod 24 cancels or exceeds the action of the centrifugal force. Therefore, the length of the spring 29 and the rubber sheet 22 in the radial direction of the wheel is a dimension when the external force is not received or a dimension slightly smaller than this.

  On the other hand, as shown in FIG. 3, when the rotation auxiliary wing 21 comes to the lower end position, the spring 29 and the rubber sheet 22 are caused to have a wheel diameter by a force that combines the gravity and the centrifugal force of the root 24 </ b> A of the movable rod 24. Stretched in the direction. As described above, the area of the rotation auxiliary wing 21 that receives the airflow decreases near the upper end position and increases near the lower end position. The auxiliary rotation blade 21 acts to promote the rotational drive of the wheel below the wheel 2 and generates a reverse rotational force that inhibits the rotational drive of the wheel on the wheel. By changing as described above, it is designed to generate a rotation assisting force that promotes rotational driving as a whole.

  In the illustrated example, the root portion 24 </ b> A of the movable rod 24 and the root portion 23 </ b> A of the fixed rod 23 protrude toward the inner surface side of the wheel cap 26, and thus the spring 29 is also disposed on the inner surface side of the wheel cap 26. A slit 27 penetrating the wheel cap 26 forms a guide structure in the wheel radial direction.

  The rubber sheet 22 can be provided with a rubber composition similar to the rubber composition constituting the tire. For example, it can be provided by a composition in which a resin such as natural rubber, butadiene rubber (BR), or styrene butadiene rubber (SBR) is blended with a reinforcing agent such as carbon black and a deterioration preventing agent. On the other hand, the fixed bar 23 and the movable bar 24 can be provided by general steel, stainless steel, aluminum alloy, or other metals, or can be provided by a molded product of fiber reinforced plastic.

  In a specific example, the wheel 2 is used for a truck, a bus, or a light truck, and has a rim diameter of 20 inches. That is, the radius from the rotating shaft to the rim tip is 0.254 m. The tire 1 attached to this is, for example, TOYO 12.00 R 20 14PR. The center position of the rotation auxiliary wing 21 in the radial direction of the wheel (the center position when there is no extension due to gravity and centrifugal force) is, for example, at 1/5 of the radius (R) of the tire around the rotation axis. is there. The rubber sheet 22 of the auxiliary rotation blade 21 has a rubber sheet body 22A having a thickness of 1 mm, a distance W between the fixed rod 23 and the movable rod 24 of 5 cm, and a dimension H protruding in the vertical direction from the outer surface of the wheel cap 26 is 3 cm. It is. The interval W here is a value when centrifugal force and gravity do not act.

  Below, the simulation performed about the rotation assistance force which the rotation auxiliary blade 21 of the said Example produces | generates is demonstrated using FIGS. Here, the tire radius R from the tire rotation axis to the tread surface is 0.3 m, the center position of the auxiliary rotation blade 21 is 1/5 of the tire radius R, and the vehicle is 60 km / h (16.67 m / sec). ). In addition, the mass of the root portion 24A of the movable rod 24 as a weight is assumed to be 0.01 kg.

  Assuming that only one rotation auxiliary blade 21 as in the above embodiment is provided on the outer surface of the wheel 2, a force (centrifugal force +) acting on the root 24 </ b> A of the movable rod 24 as a weight. Gravity) is calculated as follows. Here, the centrifugal force direction is negative, and is shown as a function with respect to the rotation angle θ from the upper end position farthest from the road surface 4. In the following formula, abs (cosθ) is the absolute value of cosθ.

θ = -90 to + 90 °: F (θ) = (-1) x 0.01 x (16.67 / 5) ² /(0.3/5) + 0.01 9.8 x abs (cosθ)
θ = 90 ~ 270 °: F (θ) = (-1) x 0.01 x (16.67 / 5) ² /(0.3/5) − 0.01 9.8 x abs (cosθ)
Further, assuming that the spring constant K of the spring 29 and the rubber sheet 22 as a whole is 18.5 (kgf / m), the fixed rod 23 and the movable rod 24 when the auxiliary rotation blade 21 comes to the lower end position. The interval W between them is about 0.105 m, and the interval W when reaching the lower end position is 0.095 m. Therefore, the dimensional change from the upper end position to the lower end position is about 10 mm. The area change rate between the upper and lower end positions of the wheel radial dimension at this time is about 10%. Here, the area change rate (%) is a value obtained by the following equation.

Area change rate (%) = (1−projected area in the traveling direction at the lower end position)
÷ Projected area in the direction of travel at the upper end position) × 100
As is known from the simulation results shown in FIG. 4, the positive rotational driving force generated when the rotational angle θ is between 90 and 270 ° is the negative rotational driving force generated when the rotational angle θ is between −90 and + 90 °. Bigger than. Therefore, the rotational drive is assisted as a whole, and the effect of reducing the rolling resistance of the tire is exhibited.

  FIG. 5 shows the results when the center position of the auxiliary rotation blade 21 is located at 1/3 of the tire diameter in the same simulation as described above. The positive rotational driving force generated when the rotational angle θ is between 90 and 270 ° is substantially equal to the negative rotational driving force generated when the rotational angle θ is between −90 and + 90 °. From this, under the condition that the area change rate is about 10%, positive driving as a whole is only performed when the center position of the auxiliary rotation blade 21 is located in a region inside 1/3 of the tire diameter. It is known that rotational force is generated.

  The wheel diameter is generally about 1/3 to 2/3 of the tire diameter. Therefore, in the case of a wheel having a smaller rim diameter than the diameter of the deposited tire to be mounted, a configuration in which the outer end of the slit 27 of the movable rod 24 is located at a location close to the rim may be employed. When the wheel diameter is about ½ to 2/3 of the tire diameter, the rotational auxiliary wings 21 may be set such that the center position in the wheel radial direction is within a range of, for example, 10 to 70% of the wheel radius. it can. When the auxiliary rotation blade 21 is sufficiently inside in the wheel radial direction, the auxiliary rotation effect can be exhibited even if the area change rate is about 5%. Although a larger area change rate is preferable, there is a limit of about 90% theoretically because there are areas of the fixed rod 23 and the movable rod 24.

Table 1 shows a simulation of the substantial rolling resistance of the tire when the position, number, and area change rate of the rotation auxiliary wings 21 are changed stepwise in the case of using the same wheel as the specific example described above. Shows the results obtained. The tire attached to the wheel is TOYO 12.00 R 20 14PR (rim size 20inch x 7.50inch), and the wheel body is of a standard form suitable for this. On the other hand, the dimensions of the auxiliary rotating blades are the same as those in the above specific example. That is, the rubber sheet 22 has a rectangular shape, the interval W between the fixed rod 23 and the movable rod 24 is 5 cm, and the protruding dimension H is 3 cm. The center position of the auxiliary rotation blade 21 is 38% or 20% (1/5) of the tire diameter based on the distance from the rotation axis, and the number of the auxiliary rotation blades 21 on one side of the wheel is four or eight. Individual. In Table 1, the rolling resistance is indicated by an index with a value of 100 when no rotation auxiliary blade is provided. The rolling resistance of the tire (TOYO 12.00 R 20 14PR) when the wheel does not have rotating auxiliary blades was measured with a drum-type rolling resistance tester under conditions of tire air pressure 700 kPa, load 2500 kgf, measurement temperature 25 ± 1 ° C. In the simulation, the effect of the rotating auxiliary blade under this condition is calculated.

  As shown in Table 1, when the distance between the center position of the auxiliary rotation blade 21 and the wheel rotation shaft 28 is 38% of the tire outer radius, if the area change rate of the auxiliary rotation blade is 10%, The actual rolling resistance of the tire was reduced by 1 to 2%. As is known from the comparison between Examples 1-1 and 1-2, it is more effective to arrange eight than to arrange four.

  On the other hand, as is known from the results of Example 2-2, when the position of the rotation auxiliary wing is close to the wheel rotation shaft 28, the area change rate of the rotation auxiliary wing is a relatively small value of 5%. The same effect of reducing rolling resistance was obtained.

  FIG. 6 schematically shows the wheel of the first modification and its related structure. In this modification, the root portion 24A 'of the movable rod 24, that is, the portion of the weight forms a magnet. If the magnetic body 5 having magnetism repelling the root portion 24A 'of the movable rod 24 is disposed in the fender portion of the vehicle body, the area change rate can be increased by the downward magnetic force. In the example shown in the figure, both the root portion 24A 'of the movable rod 24 and the magnetic body 5 of the fender portion have N poles. With such a configuration, when the rotation auxiliary wing 21 comes near the upper end position, the area of the rotation auxiliary wing 21 is reduced by pushing the movable rod 24 toward the fixed rod 23 below by repulsive magnetism. Smaller. On the other hand, when the rotation auxiliary wing 21 comes near the lower end position, the movable rod 24 is separated from the fixed rod 23 above by the repulsive magnetism, and the area of the rotation auxiliary wing 21 becomes larger.

  FIG. 7 shows a wheel 2 ′ and its rotation auxiliary blade 21 ′ according to the second modification. The rotation assist wing 21 ′ of the modified example has the same configuration as that of the above embodiment, and the relatively thick rubber sheet 22 ′ and the fixed rods 23 ′ and the movable rods 24 ′ at both ends thereof are moved rearward in the tire rotation direction. It is smoothly curved. The cross-sectional shape of the rotation auxiliary blade 21 ′ is the same as that of a “savonium-type” windmill blade for generating power using low-speed wind, for example. With such a configuration, even if the area change rate is small, the air pressure received during traveling of the vehicle is large on the lower side of the rotating shaft of the wheel and is larger on the upper side of the rotating shaft. Accordingly, a driving force in the tire rotation direction can be obtained.

It is a typical external appearance perspective view which shows the structure of the wheel of the Example in an actual driving | running | working state, and its periphery. It is a planar perspective view which shows the form of a rotation auxiliary blade in the state removed from the wheel. It is a typical vertical sectional view which shows the structure of the wheel of the Example in an actual driving | running | working state, and its periphery. The graph which shows the simulation result about the relationship between the rotation position of a rotation auxiliary blade, and the rotational driving force in the case where the center position of a rotation auxiliary blade exists in the location which is only 1/5 of the tire diameter from the rotating shaft. is there. FIG. 5 is a graph similar to FIG. 4 for the case where the center position of the auxiliary rotation blade is located at a position separated from the rotation axis by 1/5 of the tire diameter. It is a typical external view shown about the wheel of the modification 1, and its related structure. 10 is a schematic external perspective view showing a structure of a rotation auxiliary wing in a wheel of Modification Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tire 15 Tread 2 Vehicle wheel 21-1 to 21-4 Rotation auxiliary wing 22 Rubber sheet 23 Fixed rod 23A Fixed rod root 24 Movable rod 24A Movable rod root (weight) 25 Rim 26 Wheel cap 27 Movable rod root Slit for guiding 24A 28 Wheel rotating shaft 29 Coiled spring 3 Vehicle 4 Road surface

Claims (5)

  A vehicle wheel characterized in that a plurality of rotation auxiliary blades for converting a force received from an air flow during vehicle traveling into a rotational driving force are provided on an outer surface so as to be evenly distributed in the wheel circumferential direction.   The rotation auxiliary wing is provided so that an area when viewed from the vehicle traveling direction increases as the vehicle moves from the upper end position to the lower end position during vehicle traveling. Vehicle wheel.   3. The vehicle wheel according to claim 2, wherein the rotation assist wing has a change rate of the area of 5 to 90% based on a lower end position.   The rotation auxiliary wing is composed of a plurality of rod-like members aligned in the wheel radial direction and an elastic plate-like member spanned between them, and the one rod-like member is fixed to the outer surface of the wheel, and the other The vehicle wheel according to claim 2, wherein the rod-shaped member is provided so as to be movable along a wheel radial direction. The rotation auxiliary wing has a convex shape toward the front surface in the rotation direction, and a rear surface in the rotation direction forms a concave surface or a flat surface compared to the front surface. The vehicle wheel described.

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