JP2010115948A - Ground-contact property improvement device - Google Patents

Abstract

To provide a grounding improvement device that is highly versatile and can prevent an increase in the number of parts and a complicated manufacturing process.
A grounding improvement device 1 is a grounding improvement device that increases a grounding load of a vehicle, and includes projections 3 and 4 projecting radially on an outer peripheral surface of a drive shaft 2 coaxial with a tire. The lower traveling wind has a higher flow velocity than the upper traveling wind, and downforce acts on the vehicle by Bernoulli's theorem, thereby improving the ground contact.
[Selection] Figure 1

Description

  The present invention relates to a grounding improvement device suitable for being applied to vehicles such as passenger cars, trucks, and buses.

  Conventionally, there are various techniques for reducing the air resistance of a running vehicle in order to make the vehicle run stably. Of the air resistance of a running vehicle, the one with a large contribution rate is due to the negative pressure acting on the back of the vehicle when the air flow during running wraps around from the side of the vehicle and the top of the vehicle to the back of the vehicle. The generated air resistance is mentioned. Moreover, the air resistance which generate | occur | produces when the flow of air peels from a vehicle in the vehicle front surface, a vehicle side surface, and a vehicle upper surface is also mentioned.

  As a technique for reducing the former air resistance, a spoiler is provided with no gap to the vehicle at the C pillar portion forming the boundary portion between the vehicle side surface and the vehicle rear surface and the roof rear end portion forming the boundary portion between the vehicle upper surface and the vehicle rear surface. The air flow on the side surface of the vehicle and the upper surface of the vehicle is separated from the C pillar portion and the rear end portion of the roof to suppress the air from flowing from the side surface of the vehicle and the upper surface of the vehicle to the rear surface of the vehicle. .

  Furthermore, in order to drive the vehicle stably, it is required to improve the grounding property by generating downforce in the vehicle and increasing the grounding load on the road surface of the tire of the vehicle to ensure the grounding. As a technique to improve downforce, a wing is provided at the rear end of the vehicle body. However, as another technique, downforce is generated in a device related to a suspension device located under the vehicle body. Technology has been proposed.

As a technique for generating such downforce, there are techniques described in Patent Document 1 and Patent Document 2. In the prior art described in Patent Document 1, it is proposed that a U-shaped wing-like member is formed on a torsion beam extending in the vehicle width direction included in the torsion beam type suspension device to generate a down force and improve a ground load. Yes. Further, the prior art described in Patent Document 2 also describes that a wing-like member is provided at the rear end of the torsion beam.
JP 2005-297883 A JP 2006-76441 A

  However, such a conventional technique can be applied only to a vehicle in which the left and right suspension devices are connected by a torsion beam in the vehicle width direction, and a wing-like member needs to be separately added to the torsion beam. As a result, the applicable vehicles are limited, lacking versatility, and components are added to the torsion beam. This increases the number of components and complicates the manufacturing process.

  In view of the above problems, an object of the present invention is to provide a ground improvement device that is highly versatile and can prevent an increase in the number of parts and a complicated manufacturing process.

In order to solve the above problem, the grounding improvement device according to the present invention is:
A grounding improvement device for increasing a grounding load of a vehicle,
A protrusion projecting in the radial direction is provided on the outer peripheral surface of a shaft coaxial with the tire.

  The shaft refers to the rotation of the propeller shaft rotated through the transmission from the engine or motor that forms the drive system of the vehicle via the transmission in the vehicle width direction and the rotation of the left and right wheels of the vehicle. It shall refer to a drive shaft that is drivingly coupled to the propeller shaft through a differential installed for the purpose of absorbing the difference in rotational speed. The drive shaft of the vehicle is rotated by the drive shaft so that the vehicle can be driven and braked. The shaft extends in the vehicle width direction of the vehicle, and the radial direction of the shaft substantially coincides with the front-rear direction of the vehicle and thus the traveling direction.

  According to this, when the vehicle is driven, when the shaft rotates, the shaft positioned on the lower side of the floor of the vehicle in the direction opposite to the traveling direction of the vehicle is moved from the front of the vehicle to the rear. Therefore, when the projection is positioned on the upper side in the vertical direction of the vehicle as the shaft rotates, the projection opposes the air flow caused by the vehicle speed wind. Since the projections move in the direction and impede the flow of air by the vehicle speed wind and become resistance, the flow velocity of the air flow accompanying the vehicle speed wind on the upper side of the shaft is reduced.

  Furthermore, when the shaft rotates, traveling wind, that is, vehicle speed wind flowing from the front to the rear of the vehicle flows through the shaft located on the lower side of the floor of the vehicle in a direction opposite to the traveling direction of the vehicle. Therefore, when the projection is positioned on the lower side in the vertical direction of the vehicle with the rotation of the shaft, the projection runs in the same direction and rearward with respect to the air flow caused by the vehicle speed wind. Therefore, the projections act to increase the flow velocity of the air flow caused by the vehicle speed wind, so that the air flow velocity associated with the vehicle speed wind below the shaft increases.

  For this reason, based on the fact that 1 / 2ρV ^ 2 + p = constant, as shown in Equation 1, which is the so-called Bernoulli's theorem including the air density ρ, the speed of the vehicle wind, that is, the flow velocity V and the air pressure p. The pressure of the air on the lower side of the shaft is relatively lower than the pressure on the upper side of the shaft, and a down force is generated on the rotating shaft, so that the down force acts on the vehicle. Can do.

ここで、前記突起は前記シャフトの外周面において主に軸方向に延在させることとし、前記シャフトの全長に対してなるべく大きな割合において延在させることが好ましい。なお、軸方向に対し多少の傾斜角度を有する形態としても良い。

Here, it is preferable that the protrusions extend mainly in the axial direction on the outer peripheral surface of the shaft, and extend at a ratio as large as possible with respect to the entire length of the shaft. In addition, it is good also as a form which has some inclination angles with respect to an axial direction.

  According to this, in the case where the protrusion is positioned on the upper side in the vertical direction of the vehicle as the shaft rotates due to the protrusion extending in a wider range in the axial direction of the shaft, the protrusion is the vehicle speed. In order to move in the direction opposite to the air flow caused by the wind, and the protrusion exerts a function as a resistance by inhibiting the air flow caused by the vehicle speed wind, the air flow associated with the vehicle speed wind above the shaft The effect of reducing the flow rate of the can be further enhanced.

  In addition, since a projection extending from a front to a rear of the vehicle, that is, a vehicle speed wind, flows by a projection extending in a wider range in the axial direction of the shaft, the projection is driven by the rotation of the shaft. When the vehicle is located below the vertical direction of the vehicle, it moves in the same direction and in the backward direction with respect to the air flow caused by the vehicle speed wind, thereby increasing the flow velocity of the air flow caused by the vehicle speed wind. Therefore, it is possible to further enhance the effect of increasing the flow velocity of the air flow accompanying the vehicle speed wind below the shaft.

  Thus, based on Bernoulli's theorem shown in Equation 1 above, the pressure of the air on the lower side of the shaft is made relatively lower than the pressure on the upper side of the shaft, so that the rotating shaft In contrast, the effect of generating downforce can be further enhanced.

Here, in the ground improvement device,
It is preferable to provide a pair of protrusions with respect to the center of the shaft.

  According to this, one of the pair of protrusions positioned on opposite sides in the radial direction with respect to the center of the shaft causes one of the protrusions to be positioned on the upper side in the vertical direction of the vehicle as the shaft rotates. In this case, it moves in the direction against the air flow caused by the vehicle speed wind and inhibits the air flow caused by the vehicle speed wind, resulting in resistance, so the flow velocity of the air flow accompanying the vehicle speed wind on the upper side of the shaft is reduced. The effect to be made can be further enhanced.

  Further, since the other of the pair of protrusions positioned on the opposite sides in the radial direction with respect to the center of the shaft, traveling wind from the front to the rear of the vehicle, that is, vehicle speed wind flows, the other of the protrusions When the vehicle is positioned on the lower side in the vertical direction of the vehicle as the shaft rotates, it moves in the same direction and backward as the air flow caused by the vehicle speed wind. Since the flow velocity is increased, the effect of increasing the flow velocity of the air flow accompanying the vehicle speed wind on the lower side of the shaft can be further enhanced.

  Thus, one of the pair of protrusions located on the opposite side in the radial direction with respect to the center of the shaft is one of the pair of protrusions positioned on the upper side of the shaft as the shaft rotates. The other located on the lower side is alternately replaced.

  For this reason, as described above, one of the pair of protrusions moves in a direction against the air flow caused by the vehicle speed wind, and inhibits the air flow caused by the vehicle speed wind. The effect of reducing the flow velocity of the air flow accompanying the vehicle speed wind and the other of the pair of protrusions move in the same direction and in the backward direction with respect to the air flow caused by the vehicle speed wind. In order to increase the flow velocity of the air flow by the wind, the effect of increasing the flow velocity of the air flow accompanying the vehicle speed wind below the shaft is generated simultaneously and continuously in time series. The downforce can be generated by continuing in time series.

  As a result, the effect of generating downforce in the vehicle can be further enhanced, and downforce can be effectively generated by the vehicle.

  Further, in the ground contact improvement device of the present invention, downforce is generated by using the drive shaft, which is an essential constituent element in the vehicle, that is, the shaft. The problem that it can be applied only to a vehicle in which the suspension device is connected by a torsion beam can be solved. That is, the grounding improvement device of the present invention can be applied even to a vehicle that autonomously controls the attitude control of the vehicle body without using a stabilizer.

  Furthermore, in the prior art, since it becomes necessary to configure the wing-like member in a form that is separately added to the torsion beam, the applicable vehicle is limited and lacks versatility, and components are substantially added to the torsion beam. However, in the grounding improvement device of the present invention, the projections are well known in casting, forging, cutting and the like in the manufacturing process of the shaft. Since it can be configured only by additionally forming by technology, versatility can be further improved, and the increase in the number of parts and the complexity of the manufacturing process can be eliminated.

  Furthermore, in the ground contact improvement device of the present invention, it is possible to eliminate the provision of aero parts such as spoilers at the rear end of the vehicle, the roof, etc. It is possible to improve the grounding property.

  ADVANTAGE OF THE INVENTION According to this invention, the versatility is high, and the grounding improvement apparatus which can prevent causing an increase in a number of parts and complication of a manufacturing process can be provided.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic view showing an embodiment of a ground contact improvement device according to the present invention, and FIG. 2 is a schematic perspective view showing a conventional drive shaft.

  As shown in FIG. 1, the ground contact improvement device 1 includes a transmission (not shown) driven by a vehicle engine or motor, a propeller shaft (not shown) that transmits power of the transmission in the vehicle front-rear direction, and power of the propeller shaft. A differential (not shown) that is distributed in the width direction and transmitted to the left and right, a pair of left and right drive shafts 2 that are connected to the differential and drive a pair of left and right tires and wheels, and an outer peripheral surface of the drive shaft 2, On the other hand, it is provided with one projecting portion 3 and the other projecting portion 4 that are provided in a pair in the radial direction and extend linearly over the entire axial direction of the drive shaft 2.

  The drive shaft 2 constitutes the shaft of the grounding improvement device 1 of the present invention, and the projecting portion 3 and the projecting portion 4 constitute one and the other of the pair of projections of the grounding improvement device 1 of the present invention.

  In the grounding improvement device 1 of the present embodiment, the drive shaft positioned below the vehicle floor in the direction opposite to the direction in which the vehicle travels with the rotation of the drive shaft 2 during driving and braking of the vehicle. As shown in FIG. 1, a traveling wind from the front to the rear of the vehicle, that is, a vehicle speed wind flows.

  Therefore, when the projecting portion 3 is positioned on the upper side in the vertical direction of the vehicle as the drive shaft 2 rotates, the projecting portion 3 moves in a direction against the air flow caused by the vehicle speed wind, and the projecting portion 3 Therefore, the projecting portion 3 functions in the direction of decreasing the flow velocity V of the air flow accompanying the vehicle speed wind on the upper side of the drive shaft 2.

  Furthermore, when the drive shaft 2 rotates, traveling wind, that is, vehicle speed wind flowing from the front of the vehicle to the rear flows in the drive shaft 2 positioned on the lower side of the vehicle floor in a direction opposite to the direction in which the vehicle travels. Therefore, when the projecting portion 4 is positioned on the lower side in the vertical direction of the vehicle as the drive shaft 2 rotates, the projecting portion 4 is in the same direction and rearward with respect to the air flow caused by the vehicle speed wind. Since the projecting portion 4 functions to increase the flow velocity of the air flow caused by the vehicle speed wind, the air flow velocity V accompanying the vehicle speed wind on the lower side of the drive shaft 2 increases. .

  For this reason, 1 / 2ρV ^ 2 + p = constant, as shown in Equation 1 above, which is the so-called Bernoulli's theorem that includes the density of air ρ, the speed of the vehicle speed wind, that is, the flow velocity V, and the pressure p of the air. Based on this, the pressure pb of the lower air of the drive shaft 2 becomes relatively lower than the pressure pu of the upper side of the drive shaft 2, and downforce acts on the rotating drive shaft 2 from the surrounding air. Thus, downforce can be applied to the vehicle.

  Further, in the ground contact improvement device 1 of the present embodiment, the projecting portion 3 and the projecting portion 4 are extended mainly in the axial direction on the outer peripheral surface of the drive shaft 2, so that the entire length of the drive shaft 2 is increased. On the other hand, since it is made to extend in the ratio as large as possible, the following effects are obtained further.

  That is, when the projecting portion 3 is positioned on the upper side in the vertical direction of the vehicle as the drive shaft 2 rotates due to the projecting portion 3 extending in a wider range in the axial direction of the drive shaft 2, Since the portion 3 rotates and operates in a direction opposite to the air flow caused by the vehicle speed wind, the projecting portion 3 exerts a function of obstructing the air flow caused by the vehicle speed wind and functions as a resistance. The effect of reducing the flow velocity V of the airflow accompanying the vehicle speed wind on the upper side of 2 can be further enhanced.

  In addition, since the projecting portion 4 extending in a wider range in the axial direction of the drive shaft 2 causes traveling wind, that is, vehicle speed wind, flowing from the front to the rear of the vehicle, the projecting portion 4 becomes the drive shaft 2. When the vehicle is positioned on the lower side in the vertical direction of the vehicle as the vehicle rotates, the flow velocity of the air flow caused by the vehicle speed wind moves in the same direction and backward as the air flow caused by the vehicle speed wind. Since the operation of increasing V is performed, the effect of increasing the flow velocity V of the air flow accompanying the vehicle speed wind below the drive shaft 2 can be further enhanced.

  Accordingly, based on Bernoulli's theorem shown in Equation 1 described above, the pressure pb of the air on the lower side of the drive shaft 2 is made relatively lower than the pressure pu on the upper side of the drive shaft 2, The effect of generating a down force on the rotating drive shaft 2 can be further enhanced.

  As shown in FIG. 2, the normal drive shaft 22 does not have the protruding portion 3 and the protruding portion 4, so that the flow velocity on the upper side of the drive shaft 22 and the lower flow velocity on the drive shaft 22 are the same. Since both are equivalent to the flow velocity V of the air flow caused by the vehicle speed wind, the pressure of the air on the upper side of the drive shaft 2 and the pressure of the air on the lower side of the drive shaft 22 are equivalent. The downforce that occurs in the drive shaft 2 in the improvement device 1 does not occur.

  Furthermore, in the grounding improvement device 1 of the present embodiment, a pair of protrusions, that is, the protruding portion 3 and the protruding portion 4 are provided so as to be located on the opposite side in the radial direction with respect to the center of the drive shaft 2. Furthermore, the following effects can be obtained.

  In other words, the projecting portion 3 is one of a pair of projections located on the opposite sides in the radial direction with respect to the center of the drive shaft 2, so that the projecting portion 3 moves upward in the vertical direction of the vehicle as the drive shaft 2 rotates. In the case where the vehicle is located, the air flow moves in the direction opposite to the air flow caused by the vehicle speed wind, and the air flow caused by the vehicle speed wind is inhibited to become a resistance. The effect of reducing can be further enhanced.

  Further, since the projecting portion 4 located on the opposite side in the radial direction with respect to the projecting portion 3 across the center of the drive shaft 2, traveling wind from the front to the rear of the vehicle, that is, vehicle speed wind, flows. When the projecting portion 4 is positioned on the lower side in the vertical direction of the vehicle as the drive shaft 2 rotates, the projecting portion 4 winds in the same direction and rearward with respect to the air flow caused by the vehicle speed wind. Therefore, the effect of increasing the airflow velocity V associated with the vehicle speed wind below the drive shaft 2 can be further enhanced. .

  As a result, the ground improvement device 1 of the present embodiment can obtain a greater downforce more efficiently, thereby improving the steering stability and running stability of the vehicle.

  In the ground contact improvement device 1 in this embodiment, for convenience of illustration, the protruding portion 3 and the protruding portion 4 are distinguished from each other with different reference numerals. However, the protruding portion 3 and the protruding portion 4 are different from each other. One of the pair of protrusions located on the opposite sides in the radial direction with respect to the center of the drive shaft 2 and the other are formed. As the drive shaft 2 rotates, the protruding portion 3 and the protruding portion 4 are: One of the protrusions positioned on the upper side of the drive shaft 2 and the other protrusion positioned on the lower side of the drive shaft 2 are alternately switched.

  That is, in the ground contact improvement device 1 according to the present embodiment, one of the pair of protrusions as described above moves in a direction opposite to the air flow caused by the vehicle speed wind, and inhibits the air flow caused by the vehicle speed wind. Therefore, the effect that the flow velocity V of the air flow accompanying the vehicle speed wind on the upper side of the drive shaft 2 is reduced and the other of the pair of protrusions crawl in the same direction and the backward direction with respect to the air flow caused by the vehicle speed wind. Therefore, an effect of increasing the flow velocity V of the air flow caused by the vehicle speed wind on the lower side of the drive shaft 2 is to be performed. It can be generated simultaneously and continuously in time series.

  For this reason, in the ground contact improvement device 1 in the present embodiment, it is possible to generate downforce continuously in time series. As a result, the effect of generating the downforce in the vehicle can be further enhanced, and the downforce can be effectively generated by the vehicle.

  Furthermore, in the ground contact improvement device 1 of the present embodiment, the downforce is generated by using the drive shaft 2 which is an essential constituent element in a vehicle equipped with an engine or a motor. The problem that it can be applied only to a vehicle in which the left and right suspension devices are connected by a torsion beam in the width direction can be solved. That is, the grounding improvement device 1 of the present invention can be applied to a vehicle that autonomously controls the posture control of the vehicle body of the vehicle without using a stabilizer constituted by a torsion beam.

  Furthermore, in the prior art, since it has been necessary to configure the wing-like member in a form that is separately added to the torsion beam, the applicable vehicle is limited and lacks versatility, and the torsion beam is substantially reduced. However, there is a problem in that the number of parts is increased and the manufacturing process is complicated, but in the grounding improvement device 1 of this embodiment, the drive shaft 2 is manufactured. Since the projecting portion 3 and the projecting portion 4 can be configured only by additionally forming on the outer peripheral surface of the drive shaft 2 by a known technique such as casting, forging, cutting, etc. The increase in the number of parts and the complexity of the manufacturing process can be eliminated.

  Further, in the ground contact improvement device 1 of the present embodiment, it is possible to eliminate the provision of aero parts such as a spoiler for causing the down force to act on the vehicle at the rear end of the vehicle, the roof, etc. The grounding property of the vehicle can be improved while satisfying the design requirements.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions are made to the above-described embodiments without departing from the scope of the present invention. be able to.

  The present invention relates to an apparatus for improving grounding performance suitable for application to a vehicle, and can improve the grounding performance of a vehicle without providing aero parts such as a spoiler which is a design limitation. Since it is possible to provide a grounding improvement device that is high and can prevent an increase in the number of parts and a complicated manufacturing process, it is useful even when applied to various vehicles such as passenger cars, trucks, and buses. Is.

It is a mimetic diagram showing one embodiment of the grounding improvement device concerning the present invention. It is a mimetic diagram showing one embodiment of the grounding improvement device concerning the present invention.

Explanation of symbols

1 Grounding improvement device 2 Drive shaft (shaft)
3 Projection (one projection)
4 Projection (the other projection)

Claims (2)

A grounding improvement device for increasing a grounding load of a vehicle,
A grounding improvement device comprising a protrusion projecting in a radial direction on an outer peripheral surface of a shaft coaxial with a tire.   The grounding improvement device according to claim 1, wherein a pair of the protrusions are provided with respect to a center of the shaft.

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