Vehicle wheels

Abstract

To provide a vehicle wheel which enables improvement of aerodynamic performance while inhibiting pressure rise in a rim.SOLUTION: In the invention, when a portion comprising a body outer end 410 that is an axially outer end of a rim body 41 and a portion located at the axial outer side of the body outer end 410 of a rim 4 is defined as a rim outer end portion 40 and a ring-shaped portion located on the radially innermost side of an inner peripheral surface of the rim outer end portion 40 is defined as a rim inner peripheral end 4z, a wall portion 10 includes: a facing portion 11 which is disposed spaced apart in an axially outward direction from a portion of the rim inner peripheral end 4z that overlaps with an air hole 6 in an axial direction and facing the portion in the axial direction so as to serve as a wall against air flowing to the axial outer side along an inner peripheral surface 41a of the rim body 41; and an outer peripheral portion 12 extending to the radial outer side from the facing portion 11 and defining at least a part of one or more openings 13 so as to form the one or more openings 13 at the radial outer side relative to the rim inner peripheral end 4z.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle wheel.

Background Art

[0002] A cap attached to a wheel is described in, for example, Japanese Unexamined Patent Application Publication No. 2019-147460. This cap is provided with fins and slits. Thereby, the air near the fins is guided to the slits and discharged to the outside from the slits. According to this cap, both aerodynamic performance and heat dissipation performance can be achieved.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, considering the air flow in the space surrounded by the rim of the wheel, there is room for improvement in the above cap from the viewpoint of improving aerodynamic performance. An object of the present invention is to provide a vehicle wheel capable of improving aerodynamic performance while suppressing an increase in pressure inside the rim.

Means for Solving the Problems

[0005] A vehicle wheel according to a first aspect of the present disclosure comprises a cylindrical rim, a disc, and a wall portion. The disc includes a central connecting portion connected to the vehicle body, and a plurality of spokes arranged to connect the rim and the central connecting portion. The wall portion is arranged to partially block a plurality of air holes formed between the plurality of spokes. In this description, the radial direction of the rim is defined as the radial direction, and the direction parallel to the rotation axis of the rim is defined as the axial direction. Furthermore, the direction away from the vehicle centerline within the axial direction is defined as the axial outward direction, and the direction approaching the vehicle centerline within the axial direction is defined as the axial inward direction. The rim comprises a cylindrical rim body, a ring-shaped spoke connecting portion, a ring-shaped outer rim flange, and a ring-shaped inner rim flange. The spoke connecting portion extends from the axial outer end of the rim body outward in the axial direction and outward in the radial direction. The plurality of spokes are connected to the spoke connecting portion. The outer rim flange is connected to the axial outer end of the spoke connecting portion. The inner rim flange is connected to the axial inner end of the rim body in order to hold the tire together with the outer rim flange.

[0006] In this disclosure, the "rim outer end" is defined as the portion of the rim that is the outer end of the rim body in the axial direction and the portion of the rim that is axially outside the outer end of the rim body. The "rim inner end" is defined as the ring-shaped portion of the inner circumferential surface of the rim outer end that is radially inside. The wall portion comprises an opposing portion and an outer circumferential portion. The opposing portion is positioned axially apart from and opposite to the portion of the rim inner end that overlaps with the air vent in the axial direction, so as to form a wall against the air flowing axially outward along the inner circumferential surface of the rim body. The outer circumferential portion extends radially outward from the opposing portion. The outer circumferential portion defines at least a portion of the opening so as to form one or more openings that connect the inside and outside of the wall portion in the axial direction radially outside the rim inner end.

[0007] In a vehicle wheel according to a second aspect of the present disclosure, the disc is provided with a ring-shaped connecting portion. In this description, the inner end is defined as the ring-shaped portion of the inner circumferential surface of the connecting portion that is located most radially inward. The opposing portion of the wall is positioned axially outward and opposite to the inner end, which partitions a portion of the air vent, so as to form a wall against the air flowing axially outward along the inner circumferential surface of the connecting portion. The outer periphery of the wall extends radially outward from the opposing portion. The outer periphery partitions at least a portion of the opening so as to form one or more openings radially outward from the inner end. [Effects of the Invention]

[0008] As the vehicle moves forward, the pressure under the vehicle floor increases, causing air to attempt to escape through the rim. The air inside the rim is pressed against the inner circumferential surface of the rim by the centrifugal force caused by the rotation of the tire. The pressed air attempts to blow out axially outward along the inner circumferential surface of the rim. According to the first embodiment of the vehicle wheel of this disclosure, the air flowing axially outward along the inner circumferential surface of the rim body blows out from near the inner circumferential end of the rim, passes through the air vent, and strikes the opposing part of the wall. The air that strikes the opposing part moves radially outward due to centrifugal force and is discharged into the space outside the rim through the opening. According to the second embodiment of the vehicle wheel of this disclosure, the air flowing axially outward along the inner circumferential surface of the rim flows along the inner circumferential surface of the connecting part that partitions the air vent and attempts to blow out of the rim. The air attempting to blow out of the rim strikes the opposing part of the wall, moves radially outward, and is discharged outside the rim through the opening.

[0009] According to the first or second embodiment, the air inside the rim is prevented from being blown out perpendicular to the lateral flow (vehicle lateral flow). In other words, the air inside the rim is prevented from being discharged parallel to the axial direction. This reduces air resistance during vehicle operation. Furthermore, since the air inside the rim is discharged through the opening, the cooling of the brakes located inside the rim is maintained, and the rise in pressure inside the rim is suppressed. Thus, the vehicle wheel of this disclosure can improve aerodynamic performance while suppressing the rise in pressure inside the rim. [Brief explanation of the drawing]

[0010] [Figure 1] This is a diagram showing the configuration of a vehicle wheel according to the first embodiment. [Figure 2] This is a conceptual diagram showing a vehicle according to the first embodiment. [Figure 3] This is a conceptual diagram showing a cross-section of the rim and cap of the first embodiment. [Figure 4] This figure shows a cross-section of a portion of the rim and cap of the first embodiment. [Figure 5] This is a conceptual diagram showing a modified cap of the first embodiment. [Figure 6] This is a conceptual diagram showing the wall portion of a modified embodiment of the first embodiment. [Figure 7] This is a conceptual diagram showing a modified cap of the first embodiment. [Figure 8] This is a conceptual diagram showing a modified cap of the first embodiment. [Figure 9] This is a conceptual diagram illustrating the wall portion of the second embodiment. [Figure 10] This is a conceptual diagram illustrating the wall portion of the second embodiment. [Figure 11] This is a conceptual diagram showing a cross-section of a vehicle wheel according to the third embodiment. [Figure 12] This is a diagram showing the configuration of the auxiliary cap of the second embodiment. [Modes for carrying out the invention]

[0011] Hereinafter, a vehicle wheel, which is one embodiment of the present invention, will be described in detail with reference to the drawings as an embodiment for carrying out the present invention. In addition to the embodiments described below, the present invention can be carried out in various forms with various modifications and improvements based on the knowledge of those skilled in the art.

[0012] (First Embodiment) As shown in Figure 1, the vehicle wheel 9 comprises a disc 3, a cylindrical rim 4, and a cap 1. The disc 3 includes a central connecting portion 31 connected to the vehicle body and a plurality of spokes 32. The disc 3 and rim 4 of the first embodiment are one-piece and integrally formed. The central connecting portion 31 is located at the center of the disc 3. The central connecting portion 31 is attached, for example, to the hub of the vehicle body. The center of the central connecting portion 31 is located on the rotation axis P of the disc 3 and rim 4. Hereinafter, the radial direction of the rim 4 will be referred to as the radial direction, and the direction parallel to the rotation axis P, as shown in Figure 2, will be referred to as the axial direction. These radial and axial directions are orthogonal to each other. Furthermore, the direction in the axial direction that approaches the vehicle body centerline M will be referred to as the axial inner direction, and the direction that moves away from the vehicle body centerline M will be referred to as the axial outer direction. The vehicle body centerline M is a virtual straight line that passes through the center of the vehicle body and extends in the longitudinal direction. Furthermore, the circumferential direction of the rim 4 will be simply referred to as the circumferential direction. Note that "rim 4" in the above definition of direction can be replaced with "disk 3".

[0013] Multiple spokes 32 are arranged to connect the rim 4 and the central connecting portion 31. The multiple spokes 32 extend radially from the central connecting portion 31. Multiple ventilation holes 6 are formed between the multiple spokes 32. In the first embodiment, the ventilation holes 6 are partitioned by two spokes 32, the central connecting portion 31, and the rim 4. However, depending on the arrangement and shape of the spokes 32, the ventilation holes 6 may be partitioned by, for example, two spokes 32 and the rim 4.

[0014] As shown in FIG. 3, the rim 4 is formed in a cylindrical shape as a whole. FIG. 3 corresponds to a cross-section of the vehicle wheel cut in a plane including the rotation axis P. A tire 7 is held by the rim 4. The space surrounded by the inner peripheral surface 4a of the rim 4 is referred to as a rim inner space 4b. The rim 4 includes a cylindrical rim body 41, a spoke connection portion 42, an outer rim flange 43, and an inner rim flange 44. The rim body 41 is a cylindrical portion that constitutes the central portion in the axial direction of the rim 4.

[0015] At least a part of the rim body 41 constitutes a well 411. In the first embodiment, the portion including the outer end portion in the axial direction of the rim body 41 is the well 411. The well 411 is a portion provided mainly for the ease of assembling the tire. The well 411 can be said to be a portion recessed radially inward in the rim body 41. The well 411 is also called a drop well. The inner end portion in the axial direction of the rim body 41 constitutes an inner bead seat portion 412.

[0016] The spoke connection portion 42 extends axially and radially outward from the outer end portion in the axial direction of the rim body 41. The spoke connection portion 42 is a portion in the rim 4 where a plurality of spokes 32 are connected. In other words, the spoke connection portion 42 is a ring-shaped portion where a plurality of spokes 32 are in contact. More specifically, the spoke connection portion 42 includes a step formation portion 421 and a bead seat portion 422.

[0017] The step formation portion 421 extends radially outward from the outer end portion in the axial direction of the well 411. The hole of the step formation portion 421 shown in FIG. 4 is a bulge hole. The bead seat portion 422 extends axially outward from the outer end portion in the radial direction of the step formation portion 421. The bead seat portion 422 is a portion where the bead portion of the tire 7 is in close contact. A hump portion may be formed at the connection portion between the step formation portion 421 and the bead seat portion 422. In the first embodiment, the plurality of spokes 32 are integrally formed with the rim 4.

[0018] The outer rim flange 43 is ring-shaped and connected to the axial outer end of the spoke connection portion 42. In the first embodiment, the outer rim flange 43 extends axially and radially outward from the axial outer end of the spoke connection portion 42. The outer rim flange 43 constitutes the axial outer end of the rim 4.

[0019] The inner rim flange 44 is ring-shaped and connected to the axial inner end of the rim body 41. In the first embodiment, the inner rim flange 44 extends axially inward and radially outward from the axial inner end of the rim body 41. The inner rim flange 44 constitutes the axial inner end of the rim 4. The inner rim flange 44 is configured to hold the tire 7 together with the outer rim flange 43.

[0020] In this description, the outer rim portion 40 is defined as the outer rim end portion 40, which is the outermost end of the rim body 41 in the axial direction, and the portion of the rim 4 that is axially outside the outer rim end portion 410. The outer rim end portion 410 is the portion of the rim body 41 that is connected to the spoke connection portion 42. In other words, the spoke connection portion 42 can be said to extend radially outward from the outer rim end portion 410. The outer rim portion 40 is composed of the outer rim end portion 410, the spoke connection portion 42, and the outer rim flange 43. In this description, the ring-shaped portion of the inner circumferential surface of the outer rim portion 40 that is located most radially inward is defined as the inner rim end portion 4z.

[0021] As shown in Figure 4, the rim 4 of the first embodiment has a ring-shaped projection 4c that protrudes further axially outward from the outer end 410 of the main body. The projection 4c is part of the outer end 40 of the rim. The inner circumferential surface of the projection 4c is located radially inward from the inner circumferential surface of the rim body 41. Of the inner circumferential surface of the outer end 40 of the rim, the part located radially inward is the inner circumferential surface of the projection 4c. Therefore, the inner circumferential end 4z of the rim in the first embodiment is composed of the inner circumferential surface of the projection 4c. Thus, when the rim 4 is equipped with a projection 4c, the inner circumferential end 4z of the rim can be the inner circumferential surface of the projection 4c. It can also be inferred that in the case of a one-piece vehicle wheel, when the rim 4 is not equipped with a projection 4c, the inner circumferential surface of the outer end 410 of the main body often becomes the inner circumferential end 4z of the rim.

[0022] As shown in Figure 1, the cap 1 is a component that partially covers the disc 3. The cap 1 is attached to at least one of the disc 3 and the rim 4. In the first embodiment, the cap 1 is formed in a ring shape. The cap 1 is positioned on the axially outer side of the plurality of spokes 32. By positioning the cap 1 relative to the disc 3, the increase in air resistance caused by the spokes 32 during vehicle operation is suppressed, and aerodynamic performance is improved. Note that the surface refers to the axially outer surface, and the back surface refers to the axially inner surface.

[0023] The cap 1 is composed of a plurality of overlapping regions 1a, which are portions that axially overlap the air vent 6, and a plurality of non-overlapping regions 1b, which are portions that do not axially overlap the air vent 6. In the first embodiment, the non-overlapping regions 1b are portions that axially overlap the spokes 32.

[0024] The cap 1 includes a wall portion 10. The wall portion 10 is composed of all overlapping regions 1a. The wall portion 10 is positioned to partially block the multiple air holes 6. The wall portion 10 includes an opposing portion 11 and an outer peripheral portion 12. The opposing portion 11 is positioned to act as a wall against the air flowing axially outward along the inner circumferential surface 41a of the rim body 41. More specifically, the opposing portion 11 is positioned axially outward and axially opposite to the portion of the inner circumferential end 4z of the rim that overlaps axially with the air holes 6. In other words, the opposing portion 11 is positioned so as not to form an opening that connects the inside and outside of the wall portion 10 in the axial direction. The opposing portion 11 does not have an opening 13, which will be described later.

[0025] The opposing portion 11 is positioned to cover the portion of the inner circumference 4z of the rim that overlaps with the ventilation hole 6 in the axial direction. The opposing portion 11, together with the multiple spokes 32, covers the inner circumference 4z of the rim so that it is not exposed through the ventilation hole 6 in the axial direction.

[0026] The opposing portion 11 functions as a wall against air blown out axially outward from near the inner circumferential edge 4z of the rim. The opposing portion 11 has a predetermined width in the radial direction and faces both the radially inner space and the radially outer space of the inner circumferential edge 4z of the rim. The inner circumferential edge 4z of the rim faces the portion of the opposing portion 11 that excludes both the radially inner edge and the radially outer edge. The opposing portion 11 is configured to collide with air blown out axially outward along the inner circumferential surface 41a of the rim body 41.

[0027] The outer periphery 12 extends radially outward from the opposing portion 11. The outer periphery 12 defines at least a portion of the opening 13 such that one or more openings 13 that connect the inside and outside of the wall portion 10 in the axial direction are formed radially outward from the inner circumferential end 4z of the rim. In the first embodiment, one or more slits 12a are formed on the outer periphery of the cap 1. That is, one or more slits 12a are formed on the outer periphery 12. One or more openings 13 are defined by one or more slits 12a and the rim 4. The slits 12a are formed to recess radially inward from the radially outward edge of the cap 1.

[0028] In the first embodiment, one slit 12a is formed for each overlapping region 1a. In other words, the vehicle wheel 9 of the first embodiment has multiple slits 12a and openings 13 corresponding to multiple ventilation holes 6. In the first embodiment, five slits 12a and five openings 13 are formed corresponding to five ventilation holes 6. In this example, since the spokes 32 are arranged at equal intervals in the circumferential direction, the slits 12a are also arranged at equal intervals in the circumferential direction. Note that the positions of the slits 12a and openings 13 do not have to be at equal intervals. For example, the arrangement of the openings 13 can be changed according to the arrangement of the spokes 32.

[0029] One or more openings 13 are formed such that, in total, their circumferential length is greater than their radial length. In the first embodiment, the sum of the circumferential lengths of each slit 12a is greater than the sum of the radial lengths of each slit 12a. Furthermore, each slit 12a is formed such that its circumferential length is greater than its radial length. Therefore, for each opening 13, the circumferential length is greater than its radial length. Note that the shape of the opening 13 is not limited to the elongated shape described above, but may be other shapes.

[0030] A mounting portion 14 extending axially inward is formed on the back surface of the cap 1. The mounting portion 14 is used to attach the cap 1 to at least one of the disc 3 and the rim 4. As an example, a wire ring (not shown) is attached to the mounting portion 14. The cap 1 is attached to the rim 4 by the mounting portion 14 and the wire ring. The mounting portion 14 is not limited to the above and may be formed to engage with the disc 3, for example, a spoke 32. This would eliminate the need for a wire ring. Alternatively, the disc 3 and the cap 1 may be formed integrally.

[0031] The airflow around the vehicle's wheel 9 during vehicle movement will now be explained. As the vehicle moves forward, the pressure under the vehicle increases, causing air to try to escape through the rim. The air inside the rim body 41 is pressed against the inner circumferential surface 41a of the rim body 41 by the centrifugal force caused by the rotation of the tire 7. The air pressed against the inner circumferential surface 41a moves in the direction of rotation of the tire 7, and at the same time, the increasing internal pressure causes it to try to move outward in the axial direction. In other words, the air accumulated in the rim's internal space 4b tries to blow out mainly along the inner circumferential surface 41a in the axial direction.

[0032] On the other hand, in the outer rim space, which is the space outside the rim 4 in the axial direction, air flows from front to rear along the side of the tire 7 as the vehicle moves forward (see Figure 2). This airflow is called the side flow. The air discharged from inside the rim 4 outward in the axial direction collides with the side flow, resulting in air resistance when the vehicle is in motion.

[0033] According to the first embodiment, the air blown outward in the axial direction along the inner circumferential surface 41a by centrifugal force first collides with the opposing portion 11 of the wall portion 10. In other words, the air blown outward in the axial direction from near the inner circumferential end 4z of the rim collides with the opposing portion 11. The colliding air then moves radially outward of the cap 1 by centrifugal force and is discharged into the space outside the wheel through the opening 13. In other words, the direction of travel of the air discharged from inside the rim body 41 when the vehicle is running is changed to a direction inclined from the axis of rotation P. If there is no wall portion 10, the air discharged from inside the rim body 41 when the vehicle is running tends to be discharged through the air holes 6 in the axial direction, i.e., parallel to the axis of rotation P. In this case, the discharged flow collides perpendicularly with the lateral flow, and the air resistance increases.

[0034] However, according to the first embodiment, the air whose momentum in the axial direction outward is weakened by the collision with the opposing part 11 is discharged outside the rim inner space 4b through the opening 13. According to the first embodiment, the air inside the rim body 41 is suppressed from being blown out perpendicular to the lateral flow. This reduces the adverse effect on the lateral flow due to air discharge and reduces air resistance. According to the first embodiment, the air accumulated inside the rim body 41 is suppressed from being blown out in the axial direction. According to the first embodiment, when the vehicle is moving straight, the air inside the rim body 41 is suppressed from being forcefully discharged in the left and right directions of the vehicle. In other words, according to the first embodiment, aerodynamic performance can be improved. Also, since the air inside the rim body 41 is discharged from the opening 13, the cooling performance of the brakes located inside the rim body 41 is maintained, while the rise in pressure inside the rim 4 is suppressed. Thus, according to the first embodiment, aerodynamic performance can be improved while suppressing the rise in pressure inside the rim 4.

[0035] Furthermore, according to the first embodiment, each opening 13 is partitioned by a rim 4 and a slit 12a. By using the rim 4 as part of the partitioning member, it becomes easier to secure the passage area of ​​the opening 13. Also, since the wall portion 10 is made of a cap 1, it can be easily attached to an existing disc 3 or rim 4. In addition, by forming a horizontally elongated slit 12a whose circumferential length is greater than its radial length, it becomes easier to secure the passage area of ​​the opening 13. Since the opening 13 cannot be formed in the opposing portion 11, a horizontally elongated shape is preferable from the viewpoint of securing passage area.

[0036] (Other embodiments of the first embodiment) The cap 1 may be positioned, for example, on the axially outer side of the outer rim flange 43. Also, as shown in Figure 5, one or more openings 13 may be demarcated by through holes 12b formed in the outer circumference 12.

[0037] Furthermore, as shown in Figure 6, the vehicle wheel 9 may have a wall portion 10 integrally formed with at least one of the disc 3 and the rim 4, without the cap 1. In Figure 6, the wall portion 10 is integrally formed with the disc 3 so as to connect two adjacent spokes 32 in each air hole 6. The wall portion 10 extends from one spoke 32 to the next spoke 32. The wall portion 10 is positioned between two adjacent spokes 32. The opposing portion 11 extends circumferentially from one spoke 32 to the next spoke 32 so as to face the inner circumference end 4z of the rim in the axial direction. The outer circumference portion 12 is on the outer circumference side of the opposing portion 11 and defines at least a part of the opening 13.

[0038] In the example shown in Figure 6, each opening 13 is demarcated by the outer periphery 12, the rim 4, and the two spokes 32. Even with a configuration like that in Figure 6, the same effects as described above are achieved. Thus, the wall portion 10 is not limited to being composed of the cap 1, but may be integrally formed with at least one of the disc 3 and the rim 4.

[0039] As shown in Figure 7, the cap 1A may be formed by a central portion 17 and a plurality of wing portions 18 that extend radially from the central portion 17 to cover the air vent 6. The wing portions 18 include a wall portion 10. This configuration also produces the same effect as described above. A through hole 19 may be formed in the portion of the cap 1A corresponding to the radially inner portion of the air vent 6. For example, the central portion 17 of the cap 1A is connected to the central connecting portion 31 of the disc 3.

[0040] Furthermore, although not shown in the diagram, an individual cap with a wall portion 10 may be provided for each air vent 6. In other words, an individual cap may be attached to each of multiple air vents 6. In this case, the number of air vents 6 and the number of caps will be equal. In other words, a vehicle wheel may have multiple caps corresponding to multiple air vents 6. In this case, the shape of the cap may be a shape that conforms to the shape of the corresponding air vent 6 (for example, a fan shape).

[0041] Furthermore, as shown in Figure 8, a slit 12a may not be formed in the cap 1, and a single opening 13 may be demarcated by the circular outer circumference 12 and the rim 4. By positioning the cap 1 such that the entire circumference of the outer circumference 12 and the entire circumference of the rim 4 are spaced apart, a single ring-shaped opening 13 is formed. The cap 1 can be fixed to, for example, a spoke 32. This configuration also produces the same effects as described above. Note that the disc 3 is not shown in Figure 8.

[0042] (Second Embodiment) As shown in Figure 9, the disc 3 and rim 4 may be of a two-piece type. In the two-piece type, the disc 3 and rim 4 are formed separately and then joined together. Also, as shown in Figure 10, the disc 3 and rim 4 may be of a three-piece type. In the three-piece type, the rim 4 is formed by joining together an inside rim 4A and an outside rim 4B, which are separate parts from each other. In other words, in the three-piece type, the inside rim 4A, the outside rim 4B, and the disc 3 are each formed separately.

[0043] In the two-piece or three-piece type, the disc 3 is composed of a central connecting portion 31, a connecting portion 33, and a plurality of spokes 32. The connecting portion 33 is a ring-shaped portion connected to the rim 4. Each spoke 32 is arranged to connect the central connecting portion 31 and the connecting portion 33. In this description, the ring-shaped portion of the inner circumferential surface of the connecting portion 33 that is located most radially inward is referred to as the inner circumferential end 33z. The inner circumferential end 33z defines the radially outer end of the air vent 6.

[0044] The wall portion 10 comprises an opposing portion 11 and an outer peripheral portion 12. The opposing portion 11 is positioned to act as a wall against air flowing axially outward along the inner circumferential surface of the connecting portion 33. More specifically, the opposing portion 11 is positioned axially outward and opposite to the inner circumferential end 33z that partitions a part of the air vent 6. The opposing portion 11 is positioned to cover the inner circumferential end 33z. The opposing portion 11 is positioned so as not to form an opening that connects the inside and outside of the wall portion 10 in the axial direction. In other words, no opening 13 is formed in the opposing portion 11. The opposing portion 11 is positioned so as not to expose the inner circumferential end 33z in the axial direction.

[0045] In the examples shown in Figures 9 and 10, a ring-shaped cap 1 is positioned on the disc 3 and rim 4, similar to the first embodiment. Similar to the first embodiment, a portion of the cap 1 constitutes a wall portion 10. The outer peripheral portion 12 extends radially outward from the opposing portion 11 and defines at least a portion of the opening 13 such that one or more openings 13 are formed radially outward from the inner peripheral end 33z.

[0046] With this configuration, as the vehicle moves forward, the air inside the rim 4 is blown outward in the axial direction from the outer circumference of the air vent 6, i.e., near the inner circumference end 33z of the connecting portion 33, due to centrifugal force. This air, as in the first embodiment, strikes the opposing portion 11 and is discharged outside the rim 4 from the radially outer opening 13. As a result, the same effect as in the first embodiment is achieved in the second embodiment as well. The wall portion 10 may be formed integrally with the disc 3, for example. As with other aspects of the first embodiment, the configuration of the wall portion 10 in the second embodiment can be changed. As shown in Figures 9 and 10, it is preferable that the opposing portion 11 is positioned to face not only the inner circumference end 33z, but also the axially outer edge of the inner circumference surface of the connecting portion 33, in the axial direction.

[0047] (Third embodiment) As shown in Figures 11 and 12, the vehicle wheel 8 of the third embodiment includes an auxiliary cap 5 in addition to the configuration of the vehicle wheel 9 of the first embodiment. In other words, the vehicle wheel 8 comprises a disc 3, a rim 4, a cap 1, and an auxiliary cap 5. The auxiliary cap 5 can also be applied to the vehicle wheel 9 of the second embodiment.

[0048] The auxiliary cap 5 is positioned axially outward of the cap 1 so as to cover the cap 1. The auxiliary cap 5 is formed in a ring shape. The auxiliary cap 5 has an engaging portion 51 that protrudes axially inward from the back surface of the auxiliary cap 5 and engages with the cap 1. The auxiliary cap 5 has a plurality of auxiliary openings 50 that correspond to a plurality of openings 13. In the third embodiment, the auxiliary cap 5 has five auxiliary openings 50. In other words, in the third embodiment, there is a one-to-one correspondence between the openings 13 and the auxiliary openings 50. Note that the number of auxiliary openings 50 and the number of openings 13 may be different.

[0049] Each auxiliary opening 50 is located radially at the same position as the opening 13, or radially outward from the opening 13. In the examples of Figures 11 and 12, the multiple auxiliary openings 50 are located radially outward from the multiple openings 13. Also, each auxiliary opening 50 is formed at a different position from the opening 13 in the circumferential direction. The position of the opening refers to the circumferential center position of the opening. In this example, the auxiliary openings 50 and the opening 13 do not overlap in the axial direction. That is, the wall surface of the auxiliary cap 5 is located axially outward from the multiple openings 13. Note that the auxiliary openings 50 and the opening 13 may partially or completely overlap in the axial direction. The auxiliary openings 50 are demarcated by a slit 5a formed at the radial outer end of the auxiliary cap 5 and the outer rim flange 43.

[0050] According to the third embodiment, the air discharged from the opening 13 strikes the wall surface of the auxiliary cap 5 and has its direction of travel changed. The air between the cap 1 and the auxiliary cap 5 moves circumferentially due to the rotation of the tire 7. In other words, this air moves circumferentially and is discharged outside the rim 4 from the auxiliary opening 50. As a result, the direction of airflow from inside the rim 4 to outside the rim 4 tends to be in the direction of the side flow. In other words, according to the third embodiment, air resistance can be reduced.

[0051] Furthermore, in this example, the auxiliary opening 50 is located radially outward from the opening 13. The radial center of the auxiliary opening 50 is located radially outward from the radial center of the opening 13. This allows for smooth air discharge even when the air between the cap 1 and the auxiliary cap 5 moves radially outward and circumferentially due to centrifugal force.

[0052] Furthermore, the auxiliary opening 50 is partitioned by the rim 4 and the slit 5a. This makes it easier to secure a passage area for the auxiliary opening 50. Also, the auxiliary opening 50 is formed in a horizontally elongated shape, similar to the opening 13. This also makes it easier to secure a passage area for the auxiliary opening 50. Furthermore, by creating a one-to-one correspondence between the auxiliary opening 50 and the opening 13, it becomes easier to smoothly discharge air. The auxiliary opening 50 may be partitioned by a through hole provided in the auxiliary cap 5. Also, the cap 1 and the auxiliary cap 5 may be formed integrally. Also, the auxiliary cap 5 may be attached to the rim 4 by a wire ring or the like. Even if the auxiliary opening 50 and the opening 13 overlap in the axial direction, the auxiliary cap 5 can change the direction of at least some of the airflow. In each embodiment, the material of each part of the vehicle wheel, including the wall portion 10, can be arbitrarily set. The auxiliary cap 5 may be positioned on the axially outside of the outer rim flange 43. For example, the cap 1 or the auxiliary cap 5 may be attached so as to fit over the outer rim flange 43. Furthermore, the shape of the wall portion 10 is not limited to the above example. For example, the opposing portion 11 may be configured to function as a wall against air that is about to blow out axially from the air vent 6 toward the outside of the rim 4. The opposing portion 11 may include a grid, net, or small openings configured to substantially prevent air that has momentum toward the axial outward direction from passing through when the vehicle is in motion. [Explanation of Symbols]

[0053] 1...Cap, 10...Wall, 11...Opposite part, 12...Outer circumference, 12a...Slit, 13...Opening, 3...Disc, 31...Central connecting part, 32...Spoke, 33...Connection part, 33z...Inner circumference end, 4...Rim, 40...Outer end of rim, 4z...Inner circumference end of rim, 41...Rim body, 410...Outer end of body, 41a...Inner circumference surface, 42...Spoke connection part, 43...Outer rim flange, 44...Inner rim flange, 5...Auxiliary cap, 50...Auxiliary opening, 7...Tire, 8, 9...Vehicle wheel, P...Axis of rotation.

Claims

1. A cylindrical rim, A disc including a central connecting portion connected to the vehicle body, and a plurality of spokes arranged to connect the rim and the central connecting portion, A wall portion is positioned to partially block the multiple air holes formed between the multiple spokes, Equipped with, If we define the radial direction of the rim as the radial direction, the direction parallel to the rotation axis of the rim as the axial direction, the direction away from the vehicle centerline within the axial direction as the axial outer direction, and the direction approaching the vehicle centerline within the axial direction as the axial inner direction, The aforementioned rim is A cylindrical rim body, A ring-shaped spoke connecting portion extends from the outer end of the rim body in the axial direction outward and radially outward, to which the plurality of spokes are connected, A ring-shaped outer rim flange connected to the outer end of the spoke connection portion in the axial direction, In order to hold the tire together with the outer rim flange, a ring-shaped inner rim flange is connected to the axial inner end of the rim body, Equipped with, If the outer end of the rim body, which is the outer end of the rim body in the axial direction, and the portion of the rim that is axially outside the outer end of the rim body are defined as the outer rim end, and the ring-shaped portion of the inner circumferential surface of the outer rim end that is located most radially inward is defined as the inner rim end, The aforementioned wall portion is To act as a wall against the air flowing outward in the axial direction along the inner circumferential surface of the rim body, the portion of the inner circumferential end of the rim that overlaps with the air vent in the axial direction is provided with a counter portion that is spaced apart outward in the axial direction and positioned opposite to the axial direction, An outer peripheral portion that demarcates at least a part of the opening, such that one or more openings extending radially outward from the opposing portion and connecting the inside and outside of the wall portion in the axial direction are formed radially outward from the inner circumferential end of the rim, A ring-shaped auxiliary cap is positioned on the outer side of the wall portion in the axial direction, spaced apart from the wall portion and covering the wall portion. Equipped with, Multiple openings are formed, The auxiliary cap has a plurality of auxiliary openings corresponding to the plurality of openings, A vehicle wheel, wherein each of the auxiliary openings is located in the same position as the opening in the radial direction or radially outward from the opening.

2. A cylindrical rim, A disc including a central connecting portion connected to the vehicle body, a ring-shaped connecting portion connected to the rim, and a plurality of spokes arranged to connect the central connecting portion and the connecting portion, A wall portion is positioned to partially block the multiple air holes formed between the multiple spokes, Equipped with, If we define the radial direction of the rim as the radial direction, the direction parallel to the rotation axis of the rim as the axial direction, the direction away from the vehicle centerline within the axial direction as the axial outer direction, the direction approaching the vehicle centerline within the axial direction as the axial inner direction, and the ring-shaped portion located furthest inward in the radial direction of the inner circumferential surface of the connecting portion as the inner circumferential end, then, The aforementioned wall portion is To form a wall against the air flowing outward in the axial direction along the inner circumferential surface of the connecting portion, an opposing portion is provided, which is spaced apart outward in the axial direction and positioned opposite to the inner circumferential end that partitions a part of the air vent, An outer peripheral portion that demarcates at least a part of the opening, such that one or more openings extending radially outward from the opposing portion and connecting the inside and outside of the wall portion in the axial direction are formed radially outward from the inner peripheral end, A ring-shaped auxiliary cap is positioned on the outer side of the wall portion in the axial direction, spaced apart from the wall portion and covering the wall portion. Equipped with, Multiple openings are formed, The auxiliary cap has a plurality of auxiliary openings corresponding to the plurality of openings, A vehicle wheel, wherein each of the auxiliary openings is located in the same position as the opening in the radial direction or radially outward from the opening.

3. The opening is partitioned by the outer periphery and the rim, or by the outer periphery, the rim and a plurality of spokes. A vehicle wheel according to claim 1 or 2.

4. The rim and the disc are equipped with a cap attached to at least one of them, The wall portion is composed of at least a part of the cap. A vehicle wheel according to claim 1 or 2.

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