Traveling wind reduction tool

Abstract

To provide a device for reducing traveling wind directly hitting a driver by finely dispersing the traveling wind in a vortex shape and controlling a boundary layer by mounting the device without largely changing an existing saddle riding type vehicle since the traveling wind is comfortable for the driver in the saddle riding type vehicle, but too strong traveling wind causes fatigue, and wind noise hitting a helmet leads to deterioration of concentration.SOLUTION: To reduce fatigue of a driver by installing a projection in front of the driver and generating proper turbulent flow loss to enhance a windbreak effect.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a driving wind reducer that improves wind protection for saddle-ride type vehicles, thereby reducing driver fatigue. [Background technology]

[0002] In saddle-type vehicles, a windscreen is a well-known windbreak device used to reduce wind impact on the driver while riding, as it creates a physical wall to change the direction of the wind. However, negative pressure generated behind the windscreen creates vortices, which cause driving resistance and reduce the windshield's effectiveness, meaning that the driver positioned downwind is affected by this negative pressure. Therefore, the negative pressure is reduced by directing air toward the rear of the vehicle (driver's seat side) through the windscreen. Patent Document 1 is a known example of an air guide structure in which an inlet for the running wind is provided below the windscreen, an air guide path is formed between the windscreen and the vehicle body, and the running wind is guided to the back side of the windscreen through this air guide path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-193649 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned method of providing an air guide channel only reduces the negative pressure generated between the screen and the driver, and air passing over the top of the screen at the same speed as the vehicle is traveling passes near the driver's head, so a sufficient windbreak effect cannot be obtained. In this invention, a protrusion is placed on the screen to intentionally generate small vortices, and the air is slowed down and decompressed due to turbulence loss beyond the protrusion, allowing it to reach the vicinity of the driver's head. [Means for solving the problem]

[0005] A protrusion is provided in front of (upwind from) the driver's seat of a saddle-type vehicle to promote the generation of decelerated and decompressed turbulent air, and fatigue is reduced by using a wind reduction device that decelerates and decompresses the air due to turbulence loss that occurs downstream. (Figure 1) [Effects of the Invention]

[0006] By providing a protrusion in front of the driver that generates small, controllable vortices to slow down and reduce the pressure of the wind around the driver, turbulence is generated at any stage depending on the speed, and the wind around the driver is slowed down and reduced in pressure, providing a windbreak effect. Small vortices and turbulence are called turbulent loss, and part of the fluid's energy is used for vortex motion in the turbulent flow field, so the pressure loss is larger than in the case of laminar flow with the same Reynolds number, and the energy used for vortex motion is dissipated into the internal energy of the fluid, which has the effect of slowing down and reducing pressure. DETAILED DESCRIPTION OF THE INVENTION

[0007] First Embodiment The size of the windshield device varies depending on the saddle-type vehicle to which it is installed, so the size will vary depending on the vehicle. The windshield device (windscreen) in this case is approximately 500mm wide x 600mm high, and is attached by installing a protrusion on the mounting base 100mm upstream from the most downwind end in order to utilize the boundary layer after the protrusion (Figure 2-1).The mounting base measures 100mm long, 500mm wide and 3mm high, and on its top surface are four rectangular protrusions (Figure 4a) measuring 10mm long, 40mm wide and 10mm high, spaced 100mm apart and molded integrally with the mounting base so as to be symmetrical in the width direction, forming the driving wind reduction device shown in claim 3.The device is attached to the windshield device of a saddle-ride vehicle using double-sided adhesive tape on the bottom of the mounting base, or the mounting base is made from an adhesive material. In this experiment, the above size was used for the test, but the actual size may vary depending on the speed range where the effect of this invention is expected and the shape of the windshield of the vehicle, as well as the installation position and shape of the protrusion. For example, if you want to expect an effect when driving at low speeds (40km / h to 50km / h), and the shape of the protrusion is the same, the difference from this experiment would be to move the installation position further downwind, or to change the shape of the protrusion to one that more effectively promotes boundary layer separation. The size range of the protrusions is preferably 5mm to 20mm in width, 20mm to 60mm in length, and 5mm to 20mm in height, but this size will change depending on the speed range at which wind reduction is expected, so there is no limit to the size. If you want to achieve an effect at high speeds, it is also possible to arrange many shapes similar to the dimples on a golf ball. Second Embodiment Without using an attachment base, the protrusion shown in claim 2 is integrally molded with the windshield (windscreen) and installed in the same position as in the first embodiment to form a wind reduction device shown in claim 3 (Fig. 2-2), which is attached to the windshield of a saddle-type vehicle. In the first and second test configurations, deceleration and pressure reduction of the wind in the driver's seat were confirmed when driving at speeds between 30 and 100 km / h (Figure 3). In addition to the above experiments, multiple experiments were conducted by changing the shape and installation position of the protrusions, and tests were conducted on multiple shapes at various installation positions on the windscreen, such as the installation position of the driving wind reduction device on the windshield device, the size including the shape of the protrusions, the number of installations, and the distance between the protrusions when multiple protrusions are installed.It was revealed that it is possible to change the size, quantity, and timing of the vortex generated depending on the shape and installation position, so as shown in claim 2, it is necessary to optimize the shape and number to suit the driver depending on the shape of the saddle-type vehicle to which it is installed and the purpose of use, without limiting the shape, number of installations, or material. For example, when driving at low speeds, primarily in urban areas, the shape and size of the protrusions tend to be larger, whereas when driving at high speeds on expressways or on even faster circuit courses, the shape and size of the protrusions tend to be smaller and the number of protrusions tends to increase. However, the combination of these is expected to reduce wind and fatigue when driving, and it can be said that each application needs to be taken into consideration. The role of the protrusions in this invention is to utilize the principle of Karman vortex generation (Figure 4), and when a protrusion (obstacle) that changes the flow of the fluid separates at the gap in the object or where the shape changes, the vortexes that are generated by boundary layer separation at the time of separation are important, and in terms of shape, in addition to the streamlined shape used in this experiment, as a <third embodiment>, any shape can be used, such as a step resembling the surface of an insect's wing (Figure 5), or a cube-shaped object such as a cylinder, square, rectangle, or trapezoid, or a shape made by combining these, and vortices can be intentionally generated by placing a thick object perpendicular to the running wind on a windbreak (screen), and as a result, the vortices generated after the protrusion become turbulent, causing turbulent loss and creating a situation where the flow is slowed down and pressure is reduced compared to the main stream. The above turbulent flow can be stirred at the boundary between the main flow and the boundary layer, which does not pass through obstacles (protrusions) on the windbreak device, and can suppress the generation of large vortices that accompany the separation of the boundary layer that occurs when passing through the very end of the screen.Furthermore, downstream, the flow can spread to the driver's head in a decelerated and depressurized state, thereby reducing driver fatigue.As the shape depends on the speed range in which the effect is expected and the shape of the saddle-ride type vehicle, claim 1 shows a device for reducing wind pressure that uses the principle of slowing down and depressurizing the wind by providing a protrusion in front of (upwind from) the driver's seat of the saddle-ride type vehicle. [Brief explanation of the drawings]

[0008] [Figure 1] Image of a saddle-type vehicle fitted with a wind-reducing device [Figure 2] Image of mounting position and shape on saddle-type vehicles [Figure 3] Image of the change in wind speed due to wind reduction equipment [Figure 4] Illustration of vortex generation caused by protrusions and running wind [Figure 5] Image of a single protrusion using a step [Explanation of symbols]

[0009] 1. Wind reduction device using a mounting base 2. Windbreak device (windscreen) and integrally molded wind reduction device 3 Motorcycles (saddle-type vehicles) 4. Examples of protrusions that promote turbulence (top view) 5. Example of protrusions that promote turbulence (side view) 6 Windscreen 7. Generated vortex (turbulence) 8 Single protrusion using a step (top view) 8a Single protrusion using a step (side view)

Claims

1. A wind-blocking device installed in front of (upwind from) the driver's seat of a saddle-type vehicle. The device has protrusions that promote turbulence generation on top of the device, which is expected to have a wind-breaking effect. The turbulence loss that occurs downstream slows down and reduces the pressure of the wind as it moves.

2. 2. The windshield reducer according to claim 1, wherein the projection has a thickness in a direction perpendicular to the wind and is formed of a single or multiple projections.

3. 2. The windshield protection device according to claim 1, wherein the projections are integrally formed with the windshield device or have projections as vortex generators on an attachment base that is detachable from the windshield device.

Images