Bicycle rim

Abstract

The utility model relates to a bicycle rim which comprises an annular cavity, an outer ring wall, an inner ring wall and two side walls are respectively formed on the periphery of the annular cavity, and the side walls are respectively provided with a bead clamping wall which extends towards the outer side on two sides of the outer ring wall and is used for clamping a bead of a tire; the wheel rim is mainly characterized in that a plurality of polygonal resistance reducing surfaces which are connected with one another are uniformly distributed on at least the outer surface of the side wall, and according to the design, not only can excellent wind breaking and resistance reducing effects be generated when the wheel rim rotates, but also the structural strength can be ensured, and the requirement of light weight is met.

Description

TECHNICAL FIELD

[0001] The utility model relates to a bicycle component, in particular to a bicycle rim. BACKGROUND

[0002] In order to improve the riding efficiency of the bicycle, reducing the rim wind resistance has been the focus of many rim structure technical improvements, especially the wind resistance of the two side walls of the rim. The common methods include: first, reducing the shear stress of the side wall. For example, the carbon fiber rim for reducing side wind resistance disclosed in the utility model patent with the authorization announcement number CN 201385544 Y utilizes the array of corresponding air guide holes arranged at intervals between the two side frames to make the side wind pass through the air guide holes, thereby reducing the shear stress of the side wall. Although this method is theoretically feasible, in essence, setting the air guide holes on the carbon fiber material not only destroys the overall structural strength, but also has potential risks during riding and increases the difficulty and cost of production and manufacturing. Increasing the thickness of the side of the rim can improve the structural strength, but it also increases the overall weight of the rim, thereby failing to achieve the effect of lightweight.

[0003] Second, the surface shape of the side wall is utilized to reduce the friction coefficient to achieve the effect of breaking wind. For example, the flying wing wind-breaking rim, bicycle wheel and bicycle disclosed in the utility model patent with the authorization announcement number CN 219446626 U are provided with a plurality of circular arrayed wind-breaking lines on the two side surfaces of the rim. The wind-breaking lines are in the shape of a flying wing, which is expected to produce a flow guiding effect by the depth of the wing piece when encountering side wind to reduce air resistance. However, the structural design of the wind-breaking lines also faces difficulties in production and manufacturing, especially when the rim is made of carbon fiber composite material. Moreover, the limited number and area of the wind-breaking lines limit the effect of wind breaking and drag reduction.

[0004] Third, the smoothness of the side wall is increased to reduce the influence of roughness. Although increasing the smoothness can reduce the friction, when the rim rotates at a high speed, the excessively smooth side wall of the rim also increases the viscosity between the air flow and the side wall, and cannot achieve the effect of breaking wind. Overall, the effect of reducing wind resistance is still quite limited. CONTENT OF THE UTILITY MODEL

[0005] The utility model provides a bicycle rim, including a ring cavity, the ring cavity periphery respectively forms with an outer ring wall, an inner ring wall and two side walls, the side wall in the two sides of the outer ring wall each extends a tire lip clamping wall outward, be used for clamping a tire lip, its main improvement lies in: at least the side wall outer surface is uniformly distributed with a plurality of mutually connected polygonal resistance reduction surfaces.

[0006] The bicycle rim provided by this utility model utilizes a plurality of interconnected polygonal drag-reducing surfaces evenly distributed on at least the outer surface of the sidewall. A structure similar to reinforcing ribs can be generated around each polygonal drag-reducing surface to ensure good structural strength and high resistance to forces from the tire. Each polygonal drag-reducing surface can also form a concave effect, achieving excellent wind-breaking and drag-reducing effects. This reduces the viscosity and air resistance generated by the surrounding airflow on the side of the rim when the rim rotates, thereby improving riding efficiency. Attached Figure Description

[0007] Figure 1 This is a perspective view of the bicycle wheel rim of this utility model.

[0008] Figure 2 This is a radial cross-sectional view of the bicycle wheel rim of this utility model.

[0009] Figure 3 for Figure 2 Enlarged view of part A.

[0010] Figure 4 for Figure 3 Enlarged cross-sectional view.

[0011] Figure Labels

[0012] 1 wheel

[0013] 10 annular cavities

[0014] 11 Outer ring wall

[0015] 12 Inner Ring Wall

[0016] 13 sidewalls

[0017] 131-polygon drag-reducing surface

[0018] 14 Fetal Bead Adhesive Wall

[0019] t1 Circumferential radial wall

[0020] t2 Central radial wall

[0021] θ obtuse angle Detailed Implementation

[0022] like Figures 1 to 4 As shown, this utility model provides a preferred embodiment of a bicycle rim. The rim 1 includes an annular cavity 10. An outer annular wall 11, an inner annular wall 12, and two side walls 13 are formed around the annular cavity 10. Each side wall 13 extends outward from both sides of the outer annular wall 11 to form a tire bead engaging wall 14 for engaging the tire bead of a tire.

[0023] The utility model mainly improves at: at least the outer surface of side wall 13 evenly distributed with a plurality of mutually connected polygonal resistance reduction surface 131, through these full polygonal resistance reduction surface 131's structure design, can produce broken wind and resistance reduction effect when this wheel rim 1 rotates.

[0024] At least two complete polygonal resistance reduction surface 131 distribute in the radiation direction of this wheel rim 1.The radiation direction refers to the direction of radiation from the center point of this wheel rim 1 to the periphery.From the above, the size of the polygonal resistance reduction surface 131 is known, since each polygonal resistance reduction surface 131 can form an independent broken wind and resistance reduction block, therefore, a polygonal resistance reduction surface 131 that is too large will not be able to produce a sufficient number of complete broken wind and resistance reduction blocks on the side wall 13 or more areas, resulting in an impact on the broken wind and resistance reduction effect, and a polygonal resistance reduction surface 131 that is too small, although it can increase the density of the polygonal resistance reduction surface 131 formed on the side wall 13, will also reduce the broken wind and resistance reduction effect of each polygonal resistance reduction surface 131, therefore, a polygonal resistance reduction surface 131 of appropriate size can achieve a significant broken wind and resistance reduction effect on the side wall 13 or more areas.

[0025] As shown in Figure 4 At least the polygonal resistance reduction surface 131 on the outer surface of the side wall 13 has a circumferential radial wall t1 with a central position having a central radial wall t2, the thickness of the circumferential radial wall t1 is greater than the thickness of the central radial wall t2. Preferably, the thickness of the circumferential radial wall t1 and the central radial wall t2 is gradually changed. It can be understood that since the circumferential radial wall t1 of each polygonal resistance reduction surface 131 is greater than the central radial wall t2 itself, in terms of structural design, it is equivalent to forming a reinforced rib-like effect around the polygonal part of each polygonal resistance reduction surface 131, which is similar to the effect produced by a honeycomb structure, which can ensure that the side wall 13 of the wheel rim has a greater bearing capacity or deformation resistance to the force transmitted from the tire, at the same time, the thinning design of the central radial wall t1 can also achieve the effect of light weight.

[0026] Preferably, the polygonal resistance reduction surface 131 of the present embodiment extends and distributes on the outer surface of the tire lip clamping wall 14, which can increase the overall number and total area of the polygonal resistance reduction surface 131, and further improve the broken wind and resistance reduction effect, since the outer surface of the tire lip clamping wall 14 will still produce a resistance effect with the external airflow during the rotation of the wheel rim 1, therefore, designing the polygonal resistance reduction surface 131 on the outer surface of the tire lip clamping wall 14 will significantly help to improve the broken wind and resistance reduction effect.

[0027] Preferably, the rim 1 can be designed as a composite material rim, such as a generally common integral or partial carbon fiber material rim, thus further improving the structural strength and light weight of the rim 1 and enabling the polygonal drag-reducing surfaces 131 formed thereon to achieve more significant effects.

[0028] Preferably, the polygonal drag-reducing surfaces 131 can be designed as a plane or at least close to a plane. In this design, the surface of each polygonal drag-reducing surface 131 appears to be a plane from a single polygonal drag-reducing surface 131, but appears to be a groove structure from the entire rim 1 sidewall 13 or even the outer surface of the bead lock wall 14. With such a structure design, the wind-breaking and drag-reducing effects can be achieved with minimal surface concave-convex changes, and the structural strength can be maximally supported or at least minimized, and the surface structure of the polygonal drag-reducing surfaces 131 is relatively simple, thus being relatively easy to produce.

[0029] Preferably, the polygonal drag-reducing surfaces 131 can be designed as hexagons, such as regular hexagons, thus enabling more uniform distribution of the structural strength.

[0030] Preferably, as shown in Figure 4 each side of the polygonal drag-reducing surfaces 131 connected to each other forms an obtuse angle θ, which is between 169 and 175 degrees, such as 172 degrees. Similar to the above principle, such an angle design can ensure minimal surface concave-convex changes, i.e., close to the smooth surface design of the conventional rim, but can achieve good wind-breaking and drag-reducing effects, and can ensure the structural strength and meet the light weight requirement, and the surface structure is relatively simple and easy to produce.

[0031] In summary, the present application has excellent practicability in similar products, and no same structure has been found in the relevant technical data or patent literature at home and abroad. It can be understood that the above description is only for some feasible embodiments of the present application, and equivalent changes in the structure within the scope of the present application should be included in the protection scope of the present application.

Claims

1. A bicycle rim comprising a ring-shaped cavity, said ring-shaped cavity being surrounded by an outer ring wall, an inner ring wall and two side walls, respectively, said side walls each extending outwardly from two sides of said outer ring wall a tire lip engaging wall for engaging a tire lip of a tire; characterized in that: a plurality of polygonal drag-reducing surfaces are uniformly distributed on the outer surface of said side walls, said polygonal drag-reducing surfaces being connected to each other, said polygonal drag-reducing surfaces being capable of breaking wind and reducing drag when said rim is rotating.

2. The bicycle rim of claim 1, wherein, At least two complete polygonal drag-reducing surfaces are distributed in the radial direction of said rim.

3. The bicycle rim of claim 1, wherein, A circumferential radial wall is provided around said polygonal drag-reducing surfaces on the outer surface of said side walls, and a central radial wall is provided at the center of said circumferential radial wall, said circumferential radial wall having a thickness greater than that of said central radial wall.

4. The bicycle rim of claim 3, wherein, The thickness of said circumferential radial wall and said central radial wall is gradually changed.

5. The bicycle rim of claim 1, wherein, Said polygonal drag-reducing surfaces are extended and distributed on the outer surface of said tire lip engaging wall.

6. The bicycle rim of claim 1, wherein, Said rim is a composite material rim.

7. The bicycle rim of claim 1, wherein, Said polygonal drag-reducing surfaces are formed on the outer surface of said composite material.

8. The bicycle rim of claim 1, wherein, Said polygonal drag-reducing surfaces are at least close to a plane.

9. The bicycle rim of claim 1, wherein, Said polygonal drag-reducing surfaces are hexagons.

10. The bicycle rim of claim 9, wherein, Said polygonal drag-reducing surfaces are regular hexagons.

11. The bicycle rim of claim 1, wherein, Each side of said polygonal drag-reducing surfaces connected to each other forms an obtuse angle, said obtuse angle being between 169 and 175 degrees.

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