JP6295599B2 - Wheel cover damper - Google Patents

Description

  The present invention relates to a wheel cover damper used for a wheel on which a vehicle tire is mounted.

  The tire and the wheel generate vibrations in the rotational direction (hereinafter referred to as rotational fluctuations) when torque fluctuations generated by the engine are transmitted to the wheels through the drive shaft. Rotational fluctuations are transmitted to the vehicle body via the suspension, thereby generating vehicle interior noise and vehicle body vibration, which impairs vehicle comfort. In order to suppress such tire rotation fluctuations, for example, when an automatic transmission (AT) or a continuously variable transmission (CVT) is used for the transmission, it has been proposed to reduce the rigidity value of the lockup damper. . The lockup damper has a function of reducing torsional vibration of the drive system when the lockup clutch is directly connected. Alternatively, it is also considered to reduce in-vehicle sound and vibration by driving in a so-called half-clutch state called direct slip coupling.

  Further, like the dynamic damper described in Patent Document 1, a vibration ring is provided at the center of the wheel cover via an elastic member, or as in the wheel cover mounting structure described in Patent Document 2, the wheel cover is attached. It has also been proposed that a wheel cover is attached to the rim via an elastic member.

Japanese Utility Model Publication No. 1-145701 JP 2004-322679 A

  Among the prior arts, in the structure that reduces the rigidity value of the lock-up damper, the rigidity value must consider the relationship with the entire drive system such as the lock-up clutch, and only the request for suppression of in-vehicle sound and vibration is required. Because it is not a rigidity value that can be determined by the above, it does not lead to a sufficient reduction in vehicle interior noise and vibration. Among the prior arts, the structure operated by direct slip coupling has a problem in durability because the clutch is easily worn, and the fuel consumption is deteriorated, so that it cannot be used frequently.

  Since the damper of Patent Document 1 is attached to a wheel cover to be mounted by being fitted to the wheel, the damper may cause a relative displacement in the rotational direction with respect to the wheel during rotation of the tire. There is a possibility that the effect of suppressing the rotation fluctuation of the tire cannot be obtained. Moreover, since the damper is arranged at the center of the wheel in Patent Document 1, the effect of suppressing the wheel rotation fluctuation is small.

  The wheel cover of Patent Document 2 is supported by a wheel via an elastic member, and the wheel cover can move in the rotational direction and the radial direction with respect to the wheel. For this reason, if the elastic member is deformed or sags due to aging or the like, the relative position of the wheel cover with respect to the wheel becomes unstable, which may cause the wheel balance to be out of order, or may change due to contact between the members. Causes sound.

  Accordingly, an object of the present invention is to provide a wheel cover damper that can reduce vibration and noise transmitted to the inside of a vehicle during traveling.

A wheel cover damper according to the present invention is disposed in a compressed state between a wheel cover and a wheel cover that are fastened together with a wheel by a hub bolt and a hub nut (wheel nut) on an axle hub of a vehicle. And an elastic member having rubber elasticity. The wheel cover includes a center portion in which a recess for receiving the hub nut is formed at a position corresponding to the hub bolt, a cover body portion formed on a radially outer side of the center portion, and a radial direction of the cover body portion And a peripheral edge portion that is located away from the wheel over the entire circumference of the wheel cover, and the elastic member is formed on the inner surface of the cover main body portion between the peripheral edge portion and the center portion. A bolt insertion hole for inserting the hub bolt into the wheel cover is formed in the vicinity of the peripheral edge, and a taper surface of the bolt hole of the wheel and a tip tapered portion of the hub nut are formed around the bolt insertion hole It has an inner peripheral wall sandwiched between them.

In one embodiment, the wheel cover is made of metal, and includes the center portion including the bolt insertion hole, and the cover main body portion formed on the outer side in the radial direction of the center portion. The elastic member is disposed on the surface. In another embodiment, the wheel cover is made of synthetic resin, includes the center portion including the bolt insertion hole, and the cover main body portion formed on the outer side in the radial direction of the center portion, and the cover main body The elastic member may be disposed in a portion, and the inner peripheral wall of the bolt insertion hole may be formed of metal.

  According to the wheel cover damper of the present invention, the center portion of the wheel cover that functions as a mass body is fixed to the wheel by the hub bolt and the hub nut, and the wheel cover is restrained from moving in the radial direction. The wheel cover and the elastic member effectively function as a dynamic damper against fluctuations in rotation of the vehicle, and vibration and noise transmitted to the vehicle during traveling can be reduced. Even if the elastic member is deteriorated or deformed, the position of the wheel cover with respect to the wheel can be kept constant at all times, so that the wheel balance does not get out of order and no noise is generated due to contact between members.

The perspective view which shows an example of a vehicle. The front view of the wheel with a tire provided with the wheel cover damper concerning one embodiment of the present invention. Sectional drawing of a part of wheel with a tire and a suspension mechanism part in alignment with F3-F3 line of FIG. FIG. 4 is an enlarged cross-sectional view of a part of the wheel shown in FIG. 3. The figure which shows the relationship between each frequency and vehicle interior sound of the vehicle which has a wheel cover damper, and the vehicle which does not have a wheel cover damper.

Hereinafter, a vehicle including a wheel cover damper according to one embodiment of the present invention will be described with reference to FIGS. 1 to 5.
FIG. 1 shows an example of a vehicle 10. The vehicle 10 includes a pair of front wheels 12 disposed on the front side of the vehicle body 11 and a pair of rear wheels 13 disposed on the rear side of the vehicle body 11. The vehicle 10 may be an automobile equipped with either an internal combustion engine (engine) or an electric motor as a power source for traveling, or may be a hybrid vehicle using both an engine and an electric motor. The front wheel 12 and the rear wheel At least one of 13 is rotated by a power source such as an engine or an electric motor.

  The front wheel 12 and the rear wheel 13 include a wheel 20 and a tire 21 having a common configuration. In this specification, for convenience of explanation, the wheel 20 with the tire 21 mounted may be referred to as a “wheel with tire 20”. Although FIG. 2 shows the wheel 20 with a tire of the front wheel 12, the wheel 20 with a tire of the rear wheel 13 has the same configuration.

  FIG. 3 is a cross-sectional view showing an example of the wheel with tire 20 and the suspension mechanism 30. The suspension mechanism 30 shown in FIG. 3 is a McPherson strut type, but may be a suspension mechanism of other types. The suspension mechanism 30 includes a knuckle 32 provided at a lower portion of the strut 31, an axle hub 33 that is rotatably supported by the knuckle 32 via a bearing, a drive shaft 34 that rotates the axle hub 33, and the like. A constant velocity joint 36 having an axle (axle) 35 is provided between the drive shaft 34 and the axle hub 33.

  A plurality (five in FIG. 2) of hub bolts 37 are fixed to the wheel mounting portion 33 a of the axle hub 33. These hub bolts 37 are arranged at equal intervals in the circumferential direction (rotation direction) of the wheel mounting portion 33a, and protrude in a direction parallel to the axle 35 from the wheel mounting portion 33a. A hub nut (also referred to as a wheel nut) 38 is screwed to each hub bolt 37. The wheel 20 is securely fixed to the wheel mounting portion 33a of the axle hub 33 by tightening the hub nut 38 with a specified torque.

  FIG. 4 is an enlarged sectional view showing the hub bolt 37, the hub nut 38, and the like. An example of the hub nut 38 is a hexagon cap nut, a hexagonal portion 40 having a hexagonal cross section, a tip tapered portion 41 having a conical tapered surface 41a, a female screw portion 42 into which the hub bolt 37 is screwed, And a cap part 43. The taper surface 41a is inclined with respect to the axis X1 of the hub bolt 37 at an angle θ1.

  As shown in FIG. 3, the wheel 20 includes a disk portion 50 and a rim portion 51, and a bead 52 of the tire 21 is fitted to the rim portion 51. An example of the wheel 20 is a steel wheel formed by welding a steel disk portion 50 and a rim portion 51 formed by a press or the like. As another embodiment, for example, a light alloy such as an aluminum alloy or a magnesium alloy is used. It may be a cast or forged wheel made of

  Bolt holes 55 for inserting the hub bolts 37 are formed in the disk portion 50 of the wheel 20 at positions corresponding to the hub bolts 37. The tapered surface 55a of the bolt hole 55 is inclined at an angle θ2 corresponding to the angle θ1 of the tapered surface 41a of the hub nut 38.

  A wheel cover 60 is attached to the wheel 20. The wheel cover 60 has a center portion 60a formed in a region including the center of rotation C (region near the center) and a cover main body portion 60b formed on the outer side in the radial direction of the center portion 60a. It is disk-shaped when viewed from the side.

  The wheel cover 60 is made of, for example, a metal such as an aluminum alloy, and is shaped so as to have a good-looking shape and surface skin like an aluminum wheel, with an emphasis on the appearance design. The material of the wheel cover 60 may be a composite material of a metal and a synthetic resin, or a synthetic resin (reinforced plastic) reinforced with carbon fiber, glass fiber, or the like may be used. If there is no problem in weight, an iron-type wheel cover may be used.

  In the center portion 60 a of the wheel cover 60, a recess 61 that accommodates the hub nut 38 is formed at a position corresponding to the hub bolt 37. The recess 61 is circular when viewed from the side of the vehicle body 11. The inner diameter of the recess 61 is a dimension that allows insertion of a tool such as a wrench that rotates the hub nut 38.

  As shown in FIG. 4, a bolt insertion hole 63 into which the hub bolt 37 is inserted is formed in the wall 62 on the back side of the recess 61 of the wheel cover 60. The bolt insertion hole 63 is opened at a position corresponding to the hub bolt 37. Around the bolt insertion hole 63, a “mortar” -shaped inner peripheral wall 64 that is inclined according to the angle θ 1 of the tapered surface 41 a of the hub nut 38 is formed. The inner peripheral wall 64 is sandwiched between the tapered surface 41 a of the hub nut 38 and the tapered surface 55 a of the bolt hole 55. When the wheel cover 60 is made of synthetic resin, a region including the inner peripheral wall 64, for example, a wall 62 constituting the recess 61 is provided so that the inner peripheral wall 64 of the bolt insertion hole 63 can withstand the tightening torque of the hub nut 38. It is good to form with material with big rigidity, such as a metal.

  The wheel cover 60 is fastened together with the wheel 20 to the axle hub 33 by fastening means 39 including a hub bolt 37 and a hub nut 38. In other words, the disc portion 50 of the wheel 20 is overlapped on the wheel mounting portion 33a of the axle hub 33, the wheel cover 60 is overlapped thereon, and then the hub nut 38 is screwed onto the hub bolt 37 and tightened to tighten the wheel 20 and the wheel cover 60. Are fixed to the wheel mounting portion 33a of the axle hub 33, respectively.

  In a state where the wheel cover 60 is fixed to the wheel 20 by the fastening means 39, the peripheral edge portion 60 c of the wheel cover 60 is slightly separated from the wheel 20 over the entire circumference of the wheel cover 60. That is, since the peripheral edge portion 60c of the wheel cover 60 is not fixed to the wheel 20, a slight relative movement (vibration) of the cover main body portion 60b generated in the rotation direction and the axial direction of the wheel 20 can be absorbed.

  As shown in FIG. 3, an elastic member 70 having rubber elasticity is provided between the wheel 20 and the wheel cover 60. The elastic member 70 is made of, for example, synthetic rubber or elastomer, and is fixed to at least the inner surface of the cover main body 60b of the wheel 20 and the wheel cover 60 by adhesion or the like, and is compressed between the wheel 20 and the wheel cover 60. It is arranged in the state. The elastic member 70 may be bonded to the wheel 20. The elastic member 70 may be continuous over the entire circumference of the wheel cover 60 in the rotation direction, or may be divided into a plurality of locations at intervals in the rotation direction as necessary.

  The wheel cover 60 functions as a mass body (mass) of the dynamic damper with respect to the rotating wheel 20. The elastic member 70 having rubber elasticity functions as a “spring” of the dynamic damper. That is, the wheel cover 60 and the elastic member 70 constitute a wheel cover damper 71 for suppressing the rotational fluctuation of the wheel 20.

  The wheel cover damper 71 of the present embodiment has a shape and a mass of the wheel cover 60, a shape and a position of the elastic member 70, and an elasticity so that a desired vibration damping effect can be obtained according to the frequency range of in-car noise and road noise. The number of members 70 (number of divisions) is selected. In short, the wheel cover 60 and the elastic member 70 are optimized so that unpleasant noise and vibration transmitted to the inside of the vehicle due to rotational fluctuations of the wheel 20 and the tire 21 and vibrations in the axial direction of the wheel 20 can be suppressed. .

  A solid line L1 shown in FIG. 5 indicates the relationship between the frequency of the vehicle having the wheel cover damper 71 and the vehicle interior sound. A broken line L2 indicates the relationship between the frequency of the vehicle that does not have the wheel cover damper 71 and the vehicle interior sound. A in FIG. 5 is a frequency range of the in-vehicle noise generated due to the rotational fluctuation of the wheel 20 and the tire 21. In this frequency range A, the vibration generated in the rotation direction of the wheel 20 is input from the tire 21 to the suspension mechanism 30 by the damping effect of the wheel cover damper 71 by the cooperation of the wheel cover 60 and the elastic member 70. Vibrations due to rotational fluctuations and the like are suppressed, and excitation of vibrations of the vehicle body 11 is suppressed, so that the peak value of the in-car noise can be reduced.

  B in FIG. 5 is a frequency range of road noise caused by the vibration of the disk unit 50 of the wheel 20. In this frequency range B, the damping effect of the wheel cover damper 71 can be obtained by the cooperation of the wheel cover 60 and the elastic member 70 with respect to the vibration generated in the axial direction of the axle 35, and the suspension mechanism portion can be obtained from the tire 21. The vibration input to 30 is suppressed, the excitation of the vibration of the vehicle body 11 is suppressed, and the peak value of the road noise can be reduced.

  In the wheel cover damper 71 of the present embodiment, the center portion 60a of the wheel cover 60 functioning as a mass body is fixed to the center portion 20a of the wheel 20 by the hub bolt 37 and the hub nut 38. For this reason, the wheel cover 60 can keep the radial position constant with respect to the wheel 20. Therefore, even if the elastic member 70 is deformed or sags due to aging deterioration or the like, it does not cause a wheel balance to be out of order or cause abnormal noise due to contact between members.

  In carrying out the present invention, it goes without saying that specific modes such as the shape and arrangement of the wheel cover and the elastic member constituting the wheel cover damper can be variously changed, including the specific mode of the wheel. . The design of the wheel cover is not limited to the above embodiment.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 11 ... Vehicle body, 20 ... Wheel, 21 ... Tire, 33 ... Axle hub, 37 ... Hub bolt, 38 ... Hub nut, 39 ... Fastening means, 41 ... Tip taper part, 50 ... Disc part, 51 ... Rim part, 55 ... Bolt hole, 60 ... Wheel cover, 60a ... Center part, 60b ... Cover body part, 60c ... Peripheral part, C ... Center of rotation, 63 ... Bolt insertion hole, 64 ... Inner peripheral wall, 70 ... Elastic member, 71 ... Wheel Cover damper.

Claims (3)

A wheel cover that is fastened together with a wheel by a hub bolt and a hub nut to an axle hub of the vehicle;
An elastic member having rubber elasticity disposed in a compressed state between the wheel cover and the wheel;
The wheel cover is
A center part formed with a recess for accommodating the hub nut at a position corresponding to the hub bolt;
A cover body formed on the outside of the center portion in the radial direction;
Formed on the outside in the radial direction of the cover main body, and has a peripheral edge at a position away from the wheel over the entire circumference of the wheel cover;
The elastic member is disposed in the vicinity of the peripheral edge of the inner surface of the cover main body between the peripheral edge and the center ;
A bolt insertion hole for inserting the hub bolt into the wheel cover is formed,
A wheel cover damper having an inner peripheral wall sandwiched between a tapered surface of the bolt hole of the wheel and a tip tapered portion of the hub nut around the bolt insertion hole . The wheel cover is made of metal and includes the center portion including the bolt insertion hole and the cover main body portion formed on the outer side in the radial direction of the center portion, and the elastic member is disposed on the cover main body portion. The wheel cover damper according to claim 1 , wherein the wheel cover damper is formed. The wheel cover is made of a synthetic resin, and includes the center portion including the bolt insertion hole and the cover main body portion formed on the outer side in the radial direction of the center portion, and the elastic member is provided on the cover main body portion. The wheel cover damper according to claim 1 , wherein the wheel cover damper is disposed and the inner peripheral wall of the bolt insertion hole is made of metal.

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